WorldWideScience

Sample records for gnss ear tag

  1. ?? ?????????????? ???????????? GNSS-??????????? ?? ??????? ????????

    OpenAIRE

    ???????, ?. ?.; ?????, ?. ?.; ??????, ?. ?.

    2015-01-01

    ???????? ?????????? GPS/GNSS ????????????? ? ? ?????????? ????? ??????? ???????? ????????? ???? ????? - ?????????? ?????. ???????? ?? ?????????? ?? ???????????? GNSS-???????????? ??????????? ? ???? ??????: ??????? ?????????? ???????????? ???????????????? ??????, ??????? ??????????? ?????? (???????? ????????????? ???? ?????), ? ??????????? GNSS-????????????; ? ??????? ?????????? ??? ??????????? ???????? ?????? ?? ???????????. ???? ???? ?????? - ?????? ??????? ?????????? ????????? ??????, ?????...

  2. Readability of Electronic and Visual Ear Tags in Hair Goat Kids

    Directory of Open Access Journals (Sweden)

    Ferda Karakuş

    2016-05-01

    Full Text Available This study aimed to evaluate the readability of electronic and visual ear tags in hair goat kids managed under extensive conditions. A total of 74 kids were identified with electronic and visual ear tags at birth. Readability of electronic and visual ear tags was 97.3% and 94.6% in static conditions at the end of 7 months, and 96.8% and 93.5% at the end of the first year after tagging, respectively. No breakages and electronic failures occurred during this study. Infected ear rate in electronic and visual ear tags was 45.9% and 17.6%, respectively. Under the conditions of this study, electronic and visual ear tags did not fulfill the International Committee for Animal Recording (ICAR requirements (readability >98% for an official animal identification device at the end of the first year after tagging. Therefore, low animal traceability with electronic and visual ear tags was determined by this study.

  3. Cattle behaviour classification from collar, halter, and ear tag sensors

    Directory of Open Access Journals (Sweden)

    A. Rahman

    2018-03-01

    Full Text Available In this paper, we summarise the outcome of a set of experiments aimed at classifying cattle behaviour based on sensor data. Each animal carried sensors generating time series accelerometer data placed on a collar on the neck at the back of the head, on a halter positioned at the side of the head behind the mouth, or on the ear using a tag. The purpose of the study was to determine how sensor data from different placement can classify a range of typical cattle behaviours. Data were collected and animal behaviours (grazing, standing or ruminating were observed over a common time frame. Statistical features were computed from the sensor data and machine learning algorithms were trained to classify each behaviour. Classification accuracies were computed on separate independent test sets. The analysis based on behaviour classification experiments revealed that different sensor placement can achieve good classification accuracy if the feature space (representing motion patterns between the training and test animal is similar. The paper will discuss these analyses in detail and can act as a guide for future studies.

  4. [Ear tags--a prospective method for the long-term protection of livestock from ectoparasites].

    Science.gov (United States)

    Konstantinov, S A

    1987-01-01

    Ear tags are a most effective method for protecting animals from ectoparasites for a long time with minimum expenditures and without polluting the environment. The method is based on a long evaporation of highly toxic insecticides, mainly pyrethroids, homogeneously spread in the substance of the filler which by penetrating into the animal's hair provide its constant protection. Ear tags were successfully used for control of population of bloodsucking Diptera, mites and myiasis flies.

  5. Development, function and test of a static test bench for UHF-RFID ear tags

    Directory of Open Access Journals (Sweden)

    Felix Adrion

    2015-05-01

    Full Text Available Ultra-high-frequency radio frequency identification systems (UHF-RFID systems offer multiple application possibilities for animal identification. In a present joint project, UHF transponder ear tags and readers are currently being developed especially for use with cattle and pigs. An automatic test bench was developed for measuring the detection area and signal strength of various transponders, the aim being to enable with this test bench comparison of different types of UHF-transponder ear tags in different orientations to reader antennas. Described in this paper is the constructional development and functionality of the test bench as well as trials to determine reproducibility, influence of two trial parameters and suitability of the test bench for the required purpose. The results demonstrate that the test bench fulfilled all the stipulated requirements and enabled a preliminary selection of suitable types of UHF ear tags for use in practice.

  6. Release of piperonyl butoxide and permethrin from synergized ear tags on cattle and effects on horn fly mortality.

    Science.gov (United States)

    Li, Andrew Y; Miller, J Allen; Klavons, Jerome A

    2008-10-01

    A study was conducted to determine the release rates of piperonyl butoxide (PBO) and permethrin from synergized insecticidal cattle ear tags and their effects on mortality of the horn fly, Hematobia irritans irritans (L.) (Diptera: Muscidae). PBO was released from the ear tags at a higher rate than permethrin in both winter and summer trials. The cumulative release of PBO and permethrin from the ear tags at the end of 18 wk in the winter trial was 50.4 and 30.3%, respectively. The cumulative release of PBO and permethrin from the ear tags at the end of 18 wk in the summer trial was 66.7 and 44.7%, respectively. There was a significant correlation between the cumulative daily high ambient temperature (degrees C) and the cumulative release of both PBO and permethrin. Compared with the susceptible horn fly strain, the permethrin-resistant strain demonstrated 7.9- and 12.8-fold resistance to permethrin at the levels of LC50 and LC90, respectively. When exposed to filter paper wipes taken from the shoulders of cattle treated with the PBO-synergized permethrin tags from the summer trial, the resistant strain demonstrated reduced mortality compared with the susceptible strain. The mortality of the resistant strain at 2- and 3-h exposure exhibited a pattern of declining fly mortalities as a result of the decreased release of PBO and permethrin, as well as the decline in the ratio of PBO:permethrin released from the tags after 8 wk. A similar decline in horn fly mortalities was observed in the susceptible strain at 30-min exposure time that coincided with the pattern of reduced release of PBO and permethrin from the ear tags over the course of summer trial.

  7. Performance and retention of lightweight satellite radio tags applied to the ears of polar bears (Ursus maritimus)

    Science.gov (United States)

    Wiig, Øystein; Born, Erik W.; Laidre, Kristin L.; Dietz, Rune; Jensen, Mikkel Villum; Durner, George M.; Pagano, Anthony M.; Regehr, Eric V.; St. Martin, Michelle; Atkinson, Stephen N.; Dyck, Markus

    2017-01-01

    BackgroundSatellite telemetry studies provide information that is critical to the conservation and management of species affected by ecological change. Here we report on the performance and retention of two types (SPOT-227 and SPOT-305A) of ear-mounted Argos-linked satellite transmitters (i.e., platform transmitter terminal, or PTT) deployed on free-ranging polar bears in Eastern Greenland, Baffin Bay, Kane Basin, the southern Beaufort Sea, and the Chukchi Sea during 2007–2013.ResultsTransmissions from 142 out of 145 PTTs deployed on polar bears were received for an average of 69.3 days. The average functional longevity, defined as the number of days they transmitted while still attached to polar bears, for SPOT-227 was 56.8 days and for SPOT-305A was 48.6 days. Thirty-four of the 142 (24%) PTTs showed signs of being detached before they stopped transmitting, indicating that tag loss was an important aspect of tag failure. Furthermore, 10 of 26 (38%) bears that were re-observed following application of a PTT had a split ear pinna, suggesting that some transmitters were detached by force. All six PTTs that were still on bears upon recapture had lost the antenna, which indicates that antenna breakage was a significant contributor to PTT failure. Finally, only nine of the 142 (6%) PTTs—three of which were still attached to bears—had a final voltage reading close to the value indicating battery exhaustion. This suggests that battery exhaustion was not a major factor in tag performance.ConclusionsThe average functional longevity of approximately 2 months for ear-mounted PTTs (this study) is poor compared to PTT collars fitted to adult female polar bears, which can last for several years. Early failure of the ear-mounted PTTs appeared to be caused primarily by detachment from the ear or antenna breakage. We suggest that much smaller and lighter ear-mounted transmitters are necessary to reduce the risk of tissue irritation, tissue damage, and tag detachment, and

  8. First Results in the Use of Bovine Ear Notch Tag for Bovine Viral Diarrhoea Virus Detection and Genetic Analysis.

    Directory of Open Access Journals (Sweden)

    Christian Quinet

    Full Text Available Infection due to bovine viral diarrhoea virus (BVDV is endemic in most cattle-producing countries throughout the world. The key elements of a BVDV control programme are biosecurity, elimination of persistently infected animals and surveillance. Bovine viral diarrhoea (BVD is a notifiable disease in Belgium and an official eradication programme started from January 2015, based on testing ear notches sampled during the official identification and registration of calves at birth. An antigen-capture ELISA test based on the detection of BVDV Erns protein is used. Ear notch sample may also be used to characterize the genotype of the calf when appropriate elution/dilution buffer is added. Both BVDV antigen-ELISA analysis and animal traceability could be performed.With regards to the reference protocol used in the preparation of ear notch samples, alternative procedures were tested in terms of BVDV analytic sensitivity, diagnostic sensitivity and specificity, as well as quality and purity of animal DNA.The Allflex DNA Buffer D showed promising results in BVDV diagnosis and genome analyses, opening new perspectives for the livestock industry by the exploitation of the animal genome. Due to the high number of cattle involved in the Belgian official BVDV eradication programme based on ear notch tags sample, a large database on both BVDV status of newborn calves and cattle genome could be created for subsequent different uses (e.g. traceability, determination of parentage, genetic signatures throughout the genome associated with particular traits evolving through a more integrated animal health.

  9. The ability of insecticidal ear-tags, collar, and pour-ons to control flies (Diptera; Musci¬dae) and to prevent Summer Mastitis in heifers

    DEFF Research Database (Denmark)

    Jespersen, Jørgen Brøchner; Jensen, Karl-Martin Vagn

    1987-01-01

    Jespersen, J.B. and K.-M. Vagn Jensen, 1987. The ability of insectici¬dal ear-tags, collar, and pour-ons to control flies (Diptera; Musci¬dae) and to prevent Summer Mastitis in heifers. In Thomas, G., H. J. Over, U. Vecht and P. Nansen (Editor): Summer Masitits (ISBN O-89838-982-8) pp. 166-172....

  10. Technical note: Validation of an ear-tag accelerometer sensor to determine rumination, eating, and activity behaviors of grazing dairy cattle.

    Science.gov (United States)

    Pereira, G M; Heins, B J; Endres, M I

    2018-03-01

    The objective of this study was to validate an ear-tag accelerometer sensor (CowManager SensOor, Agis Automatisering BV, Harmelen, the Netherlands) using direct visual observations in a grazing dairy herd. Lactating crossbred cows (n = 24) were used for this experiment at the University of Minnesota West Central Research and Outreach Center grazing dairy (Morris, MN) during the summer of 2016. A single trained observer recorded behavior every minute for 6 h for each cow (24 cows × 6 h = 144 h of observation total). Direct visual observation was compared with sensor data during August and September 2016. The sensor detected and identified ear and head movements, and through algorithms the sensor classified each minute as one of the following behaviors: rumination, eating, not active, active, and high active. A 2-sided t-test was conducted with PROC TTEST of SAS (SAS Institute Inc., Cary, NC) to compare the percentage of time each cow's behavior was recorded by direct visual observation and sensor data. For total recorded time, the percentage of time of direct visual observation compared with sensor data was 17.9 and 19.1% for rumination, 52.8 and 51.9% for eating, 17.4 and 11.9% for not active, and 7.9 and 21.1% for active. Pearson correlations (PROC CORR of SAS) were used to evaluate associations between direct visual observations and sensor data. Furthermore, concordance correlation coefficient (CCC), bias correction factors, location shift, and scale shift (epiR package of R version 3.3.1; R Foundation for Statistical Computing, Vienna, Austria) were calculated to provide a measure of accuracy and precision. Correlations between visual observations for all 4 behaviors were highly to weakly correlated (rumination: r = 0.72, CCC = 0.71; eating: r = 0.88, CCC = 0.88; not active: r = 0.65, CCC = 0.52; and active: r = 0.20, CCC = 0.19) compared with sensor data. The results suggest that the sensor accurately monitors rumination and eating behavior of grazing dairy

  11. Your Ears

    Science.gov (United States)

    ... Outer Ear: Catch the Wave The Middle Ear: Good Vibrations The Inner Ear: Nerve Signals Start Here Day or Night, Ears Keep You Upright Three Cheers for the Ears! en español Tus oídos Did you hear something? Maybe the sound you heard was as quiet as your cat licking her paws. Or maybe it was loud, ...

  12. Continental Deformation in Madagascar from GNSS Observations

    Science.gov (United States)

    Stamps, D. S.; Rajaonarison, T.; Rambolamanana, G.; Herimitsinjo, N.; Carrillo, R.; Jesmok, G.

    2015-12-01

    D.S. Stamps, T. Rajaonarison, G. Rambolamanana Madagascar is the easternmost continental segment of the East African Rift System (EARS). Plate reconstructions assume the continental island behaves as a rigid block, but studies of geologically recent kinematics suggest Madagascar undergoes extension related to the broader EARS. In this work we test for rigidity of Madagascar in two steps. First, we quantify surface motions using a novel dataset of episodic and continuous GNSS observations that span Madagascar from north to south. We established a countrywide network of precision benchmarks fixed in bedrock and with open skyview in 2010 that we measured for 48-72 hours with dual frequency receivers. The benchmarks were remeasured in 2012 and 2014. We processed the episodic GNSS data with ABPO, the only continuous GNSS station in Madagascar with >2.5 years of data, for millimeter precision positions and velocities at 7 locations using GAMIT-GLOBK. Our velocity field shows 2 mm/yr of differential motion between southern and northern Madagascar. Second, we test a suite of kinematic predictions from previous studies and find residual velocities are greater than 95% uncertainties. We also calculate angular velocity vectors assuming Madagascar moves with the Lwandle plate or the Somalian plate. Our new velocity field in Madagascar is inconsistent with all models that assume plate rigidity at the 95% uncertainty level; this result indicates the continental island undergoes statistically significant internal deformation.

  13. GNSS baseret roadpricing

    DEFF Research Database (Denmark)

    Lahrmann, Harry

    2012-01-01

    Notatet giver en vurdering af teknologi, afgiftsstrukturer, fiskale aspekter, snyd og overvågning som input til Trængselskommissionens arbejdsgruppe 6's arbejde med GNSS baseret roadpricing......Notatet giver en vurdering af teknologi, afgiftsstrukturer, fiskale aspekter, snyd og overvågning som input til Trængselskommissionens arbejdsgruppe 6's arbejde med GNSS baseret roadpricing...

  14. Comparing different types of patagial tags for use on vultures ...

    African Journals Online (AJOL)

    Raptor research often requires identifying individuals. Researchers place patagial tags on raptors to facilitate such identification. Researchers in southern African use two main types of patagial tags: hard plastic ear tags originally designed for cattle and soft vinyl tags. We deployed both types of tags on vultures in Botswana.

  15. Comparing different types of patagial tags for use on vultures ...

    African Journals Online (AJOL)

    Researchers in southern African use two main types of patagial tags: hard plastic ear tags originally designed for cattle and soft vinyl tags. We deployed both types of tags on vultures in Botswana. Based on our observations, we recommend using soft vinyl tags as they appear to be more aerodynamic and can be read from ...

  16. Ear Infection (Middle Ear)

    Science.gov (United States)

    ... back of the nose believed to play a role in immune system activity. This function may make them particularly vulnerable to infection, inflammation and swelling. Because adenoids are near the ... likely to play a role in ear infections in children because children have ...

  17. Swimmer's Ear

    Science.gov (United States)

    ... Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español Swimmer's Ear KidsHealth / ... español Otitis del nadador What Is Swimmer's Ear? Swimmer's ear is an infection of the ear canal . If you stick your ...

  18. Pierced Ears

    Science.gov (United States)

    ... how they do things is to watch another customer get his or her ears pierced. Without these precautions, you run the risk of getting infected ears. Metal Matters Your first earrings should have gold posts (the ...

  19. Airplane Ear

    Science.gov (United States)

    ... your flight. If you're prone to severe airplane ear and must fly often, your doctor may surgically place tubes in your eardrums to aid fluid drainage, ventilate your middle ear, and equalize the ... prevent airplane ear These additional tips can help young children ...

  20. Ear Tubes

    Science.gov (United States)

    ... of the ear drum or eustachian tube, Down Syndrome, cleft palate, and barotrauma (injury to the middle ear caused by a reduction of air pressure, ... specialist) may be warranted if you or your child has experienced repeated ... fluid in the middle ear, barotrauma, or have an anatomic abnormality that ...

  1. Billfish Tagging

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The SWFSC's constituent-based Billfish Tagging Program began in 1963 and since that time has provided conventional spaghetti type tags and tagging supplies to...

  2. Evoluzione dei sistemi GNSS

    Directory of Open Access Journals (Sweden)

    Gianluca Pititto

    2010-03-01

    Full Text Available Evolution of GNSS systems With this article GEOmedia is starting a review on the latest updates concerning GNSS technology. Since the first GPS satellites, the evolution of GNSS sector witnessed the grow of other constellations: GLONASS, Beidou (Compass and Galileo. The development of positioning techniques even brought to the creation of specific Augmentation Systems, capable of the enhancement of the localization signals (GBAS and SBAS. The aim of this review is to provide a general-to-particular knowledge of all the positiong and augmentation systems, from a historical point of view to real applications.

  3. CDDIS_GNSS_products_orbit_rapid

    Data.gov (United States)

    National Aeronautics and Space Administration — Precise satellite orbits derived from analysis of Global Navigation Satellite System (GNSS) data. Analysis Centers (ACs) of the International GNSS Service (IGS)...

  4. CDDIS_GNSS_products_orbit_final

    Data.gov (United States)

    National Aeronautics and Space Administration — Precise satellite orbits derived from analysis of Global Navigation Satellite System (GNSS) data. Analysis Centers (ACs) of the International GNSS Service (IGS)...

  5. CDDIS_GNSS_products_orbit_realtime

    Data.gov (United States)

    National Aeronautics and Space Administration — Precise satellite orbits derived from analysis of Global Navigation Satellite System (GNSS) data. Analysis Centers (ACs) of the International GNSS Service (IGS)...

  6. CDDIS_GNSS_products_orbit_ultrarapid

    Data.gov (United States)

    National Aeronautics and Space Administration — Precise satellite orbits derived from analysis of Global Navigation Satellite System (GNSS) data. Analysis Centers (ACs) of the International GNSS Service (IGS)...

  7. CDDIS_GNSS_products_positions

    Data.gov (United States)

    National Aeronautics and Space Administration — Weekly station positions and velocity solutions in Software INdependent EXchange (SINEX) format derived from analysis of Global Navigation Satellite System (GNSS)...

  8. Ear Problems

    Science.gov (United States)

    ... Infants and Children Chest Pain, Acute Chest Pain, Chronic Cold and Flu Cough Diarrhea Ear Problems Elimination Problems Elimination Problems in Infants and Children Eye Problems Facial Swelling Feeding Problems in Infants ...

  9. Ear examination

    Science.gov (United States)

    ... to the side, or the child's head may rest against an adult's chest. Older children and adults may sit with the head tilted toward the shoulder opposite the ear being examined. The provider will ...

  10. GNSS Software Receiver for UAVs

    DEFF Research Database (Denmark)

    Olesen, Daniel Madelung; Jakobsen, Jakob; von Benzon, Hans-Henrik

    2016-01-01

    This paper describes the current activities of GPS/GNSS Software receiver development at DTU Space. GNSS Software receivers have received a great deal of attention in the last two decades and numerous implementations have already been presented. DTU Space has just recently started development of ...... of our own GNSS software-receiver targeted for mini UAV applications, and we will in in this paper present our current progress and briefly discuss the benefits of Software Receivers in relation to our research interests.......This paper describes the current activities of GPS/GNSS Software receiver development at DTU Space. GNSS Software receivers have received a great deal of attention in the last two decades and numerous implementations have already been presented. DTU Space has just recently started development...

  11. Ear Infections

    Science.gov (United States)

    ... can cause your child’s eardrum to rupture or pop, leaving a hole in the ear. The initial pop hurts, but actually relieves the pressure and pain. ... turns up the volume of the TV or music, is not responding to softer sounds or is ...

  12. Cosmetic ear surgery

    Science.gov (United States)

    Otoplasty; Ear pinning; Ear surgery - cosmetic; Ear reshaping; Pinnaplasty ... Cosmetic ear surgery may be done in the surgeon's office, an outpatient clinic, or a hospital. It can be performed under ...

  13. Beamsteerable GNSS Radio Occultation ASIC

    Data.gov (United States)

    National Aeronautics and Space Administration — We will develop an integrated RF ASIC to enable high quality radio occultation (RO) weather observations using the Global Navigations System Satellite (GNSS)...

  14. CDDIS_GNSS_products_erp

    Data.gov (United States)

    National Aeronautics and Space Administration — Earth Rotation Parameters (ERPs) derived from analysis of Global Navigation Satellite System (GNSS) data. These products are the generated by analysis centers in...

  15. CDDIS_GNSS_hourly_data

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Navigation Satellite System (GNSS) data consists of the U.S. Global Positioning System (GPS) and the Russian GLObal NAvigation Satellite System (GLONASS)...

  16. CDDIS_GNSS_highrate_data

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Navigation Satellite System (GNSS) data consists of the U.S. Global Positioning System (GPS) and the Russian GLObal NAvigation Satellite System (GLONASS)...

  17. CDDIS_GNSS_satellite_data

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Navigation Satellite System (GNSS) data consists of the U.S. Global Positioning System (GPS) and the Russian GLObal NAvigation Satellite System (GLONASS)...

  18. CDDIS_GNSS_daily_data

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Navigation Satellite System (GNSS) data consists of the U.S. Global Positioning System (GPS) and the Russian GLObal NAvigation Satellite System (GLONASS)...

  19. CDDIS_GNSS_products_troposphere

    Data.gov (United States)

    National Aeronautics and Space Administration — Troposphere Zenith Path Delay (ZPD) values by site derived from analysis of Global Navigation Satellite System (GNSS) data. These products are the generated by...

  20. Ear infection - chronic

    Science.gov (United States)

    Middle ear infection - chronic; Otitis media - chronic; Chronic otitis media; Chronic ear infection ... blocked, fluid can build up. When this happens, infection can occur. A chronic ear infection develops when ...

  1. Ear infection - acute

    Science.gov (United States)

    ... Family history of ear infections Not being breastfed Pacifier use Recent ear infection Recent illness of any ... lead to fewer ear infections. DO NOT use pacifiers. Breastfeed -- this makes a child much less prone ...

  2. GNSS Positioning - Status and Features

    NARCIS (Netherlands)

    Lemmens, M.

    2012-01-01

    Nowadays, GNSS receivers have scores – and often more than one hundred – of channels, enabling them to track GPS, Glonass, Galileo and Compass signals simultaneously. The whole workfl ow from satellite tracking to calculating the coordinates of the position in a preferred reference system can be

  3. Play it by Ear

    DEFF Research Database (Denmark)

    Kammersgaard, Nikolaj Peter Iversen; Kvist, Søren Helstrup; Thaysen, Jesper

    2014-01-01

    The first antenna for ear-to-ear communication with a standard Bluetooth chip has the potential to improve hearing aid technology.......The first antenna for ear-to-ear communication with a standard Bluetooth chip has the potential to improve hearing aid technology....

  4. GNSS/RFID Active Transponder Design

    Directory of Open Access Journals (Sweden)

    Lukas Vojtech

    2015-01-01

    Full Text Available The paper describes a design of global navigation satellite system (GNSS/Radio frequency identification (RFID active transponder which is primarily designed for localization of objects as a part of localization system designated for efficient handling of situations with mass casualties. The precise localization is improved by differential GNSS. The block diagram of such GNSS/RFID active transponder is described including main operation procedures of the firmware. Measurement of the localization by algorithms of RTKLIB library and by algorithms of GNSS module is compared. Dynamic tests, i.e. GNSS/RFID active transponder placed in the moving car (50~kmph, and static tests, i.e. GNSS/RFID active transponder placed in the position for 15~min, are performed.

  5. GNSS/RFID Active Transponder Design

    OpenAIRE

    Lukas Vojtech; Jiri Skapa; Radoslav Bortel; Tomas Korinek; Marek Neruda; Jiri Hajek; Daniel Lopour

    2015-01-01

    The paper describes a design of global navigation satellite system (GNSS)/Radio frequency identification (RFID) active transponder which is primarily designed for localization of objects as a part of localization system designated for efficient handling of situations with mass casualties. The precise localization is improved by differential GNSS. The block diagram of such GNSS/RFID active transponder is described including main operation procedures of the firmware. Measurement of the localiza...

  6. SOGRA - Supporting Optimized GNSS Research in Africa

    Science.gov (United States)

    2014-12-08

    AFRL-AFOSR-UK-TR-2015-0022 SOGRA – Supporting Optimized GNSS Research in Africa Rui M. Fernandes Universidade da Beira...DATES COVERED (From – To) 15 August 2009 – 8 December 2014 4. TITLE AND SUBTITLE SOGRA – Supporting Optimized GNSS Research in Africa 5a...Prescribed by ANSI Std. Z39-18 REPORT FINAL REPORT SOGRA Supporting Optimized GNSS Research in Africa November 2014

  7. Ear Infection and Vaccines

    Science.gov (United States)

    ... an ENT Doctor Near You Ear Infection and Vaccines Ear Infection and Vaccines Patient Health Information News ... or may need reinsertion over time. What about vaccines? A vaccine is a preparation administered to stimulate ...

  8. External Otitis (Swimmer's Ear)

    Science.gov (United States)

    ... Abbreviations Weights & Measures ENGLISH View Professional English Deutsch Japanese Espaniol Find information on medical topics, symptoms, drugs, ... A doctor's examination of the ear canal Sometimes culture of a sample from the ear canal The ...

  9. Yellowtail Tagging Data (MRDBS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Yellowtail Flounder Tagging Program began in 2003 and works with commercial fishermen to tag and release yellowtaiI flounder with pink and yellow disc tags or...

  10. Swimmer's Ear (External Otitis)

    Science.gov (United States)

    ... Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español ... español Otitis del nadador (otitis externa) What Is Swimmer's Ear? Swimmer's ear is an infection of the ear canal, the tubular opening that ...

  11. BQC : A new multi-GNSS data quality checking toolkit

    NARCIS (Netherlands)

    Liu, H.; Tang, G.; Imparato, D.; Cui, H.; Song, B.; Rizos, C.

    2014-01-01

    Multi-GNSS networks, for example M-GEX and iGMAS, are set up and grow quickly with the development of new navigation systems and multi-GNSS receivers. It is unavoidable that GNSS signals are deteriorated by several error sources. Thus GNSS network operators, data users and receiver designers all

  12. Evolutionary Progression Towards an Integrated GNSS

    Science.gov (United States)

    Remeikis, K.; Sloan, J.; Laffaiteur, M.; Nadeau, P.; Loescher, A.

    2002-01-01

    This paper addresses strategic and technical decisions that have been taken recently on Global Navigation Satellite System (GNSS). Progress and policy challenges for a GNSS encountered by the International Civil Aviation Organization (ICAO) will be examined. An overview will be given of ICAO's long-term strategy for the implementation of GNSS at all levels, global and regional. Besides the technical, political and legal harmonization, it is essential that the necessary frequencies are made available and are adequately protected once GNSS is operational. The paper highlights the importance of frequency issues for the development of GNSS, both in terms of the requirement for additional frequency allocations as well as the need to ensure that the operation of GNSS is not interfered with by other radio communications services. At the last WRC 2000 in Istanbul, the band 5010 to 5030 MHz was allocated for GNSS services. The tentative Galileo frequency structure and signal plan using common center frequencies with GPS will enhance interoperability for future user of an integrated GNSS consisting of GPS and Galileo. Galileo will be fully compatible with GPS, but independent from it. In addition, a global satellite navigation system, even a civilian one as Galileo, has to consider global security aspects. The dual-nature of satellite navigation is used in critical infrastructure where an uninterrupted service of applications based on it, is absolutely vital. Disruption of GNSS services is a potential threat for economy, safety and security related applications. Without the possibility of transparency and interoperability, GNSS system will not meet the safety objectives defined by FANS Committee. Clear policy and legal principles on standardization need to be elaborated in the legal framework to govern GNSS implementation. Recommendations about what changes to the current operational structure would be most appropriate for the future in order to develop a true GNSS will be

  13. CDDIS_GNSS_products_ionosphere_final

    Data.gov (United States)

    National Aeronautics and Space Administration — Satellite and receiver clock products derived from analysis of Global Navigation Satellite System (GNSS) data. These products are the generated by analysis centers...

  14. CDDIS_GNSS_products_clocks_rapid

    Data.gov (United States)

    National Aeronautics and Space Administration — Satellite and receiver clock products derived from analysis of Global Navigation Satellite System (GNSS) data. These products are the generated by analysis centers...

  15. CDDIS_GNSS_products_clocks_final

    Data.gov (United States)

    National Aeronautics and Space Administration — Satellite and receiver clock products derived from analysis of Global Navigation Satellite System (GNSS) data. These products are the generated by analysis centers...

  16. GNSS remote sensing theory, methods and applications

    CERN Document Server

    Jin, Shuanggen; Xie, Feiqin

    2014-01-01

    This book presents the theory and methods of GNSS remote sensing as well as its applications in the atmosphere, oceans, land and hydrology. It contains detailed theory and study cases to help the reader put the material into practice.

  17. CDDIS_GNSS_products_ionosphere_predicted

    Data.gov (United States)

    National Aeronautics and Space Administration — Ionosphere Total Electron Content (TEC) grids derived from analysis of Global Navigation Satellite System (GNSS) data. These products are the generated by analysis...

  18. CDDIS_GNSS_products_ionosphere_rapid

    Data.gov (United States)

    National Aeronautics and Space Administration — Ionosphere Total Electron Content (TEC) grids derived from analysis of Global Navigation Satellite System (GNSS) data. These products are the generated by analysis...

  19. INS/CNS/GNSS integrated navigation technology

    CERN Document Server

    Quan, Wei; Gong, Xiaolin; Fang, Jiancheng

    2015-01-01

    This book not only introduces the principles of INS, CNS and GNSS, the related filters and semi-physical simulation, but also systematically discusses the key technologies needed for integrated navigations of INS/GNSS, INS/CNS, and INS/CNS/GNSS, respectively. INS/CNS/GNSS integrated navigation technology has established itself as an effective tool for precise positioning navigation, which can make full use of the complementary characteristics of different navigation sub-systems and greatly improve the accuracy and reliability of the integrated navigation system. The book offers a valuable reference guide for graduate students, engineers and researchers in the fields of navigation and its control. Dr. Wei Quan, Dr. Jianli Li, Dr. Xiaolin Gong and Dr. Jiancheng Fang are all researchers at the Beijing University of Aeronautics and Astronautics.

  20. CDDIS_GNSS_products_clocks_realtime

    Data.gov (United States)

    National Aeronautics and Space Administration — Satellite and receiver clock products derived from analysis of Global Navigation Satellite System (GNSS) data. These products are the generated by analysis centers...

  1. Middle Ear Infections (For Parents)

    Science.gov (United States)

    ... happen when viruses or bacteria get into the middle ear, the space behind the eardrum. When a child has an ear infection (also called otitis media ), ... down can cause painful pressure changes in the middle ear. Older kids can complain about ear pain, but a younger child might just tug at the ear or be ...

  2. SNR and Standard Deviation of cGNSS-R and iGNSS-R Scatterometric Measurements

    Directory of Open Access Journals (Sweden)

    Alberto Alonso-Arroyo

    2017-01-01

    Full Text Available This work addresses the accuracy of the Global Navigation Satellite Systems (GNSS-Reflectometry (GNSS-R scatterometric measurements considering the presence of both coherent and incoherent scattered components, for both conventional GNSS-R (cGNSS-R and interferometric GNSS-R (iGNSS-R techniques. The coherent component is present for some type of surfaces, and it has been neglected until now because it vanishes for the sea surface scattering case. Taking into account the presence of both scattering components, the estimated Signal-to-Noise Ratio (SNR for both techniques is computed based on the detectability criterion, as it is done in conventional GNSS applications. The non-coherent averaging operation is considered from a general point of view, taking into account that thermal noise contributions can be reduced by an extra factor of 0.88 dB when using partially overlapped or partially correlated samples. After the SNRs are derived, the received waveform’s peak variability is computed, which determines the system’s capability to measure geophysical parameters. This theoretical derivations are applied to the United Kingdom (UK TechDemoSat-1 (UK TDS-1 and to the future GNSS REflectometry, Radio Occultation and Scatterometry on board the International Space Station (ISS (GEROS-ISS scenarios, in order to estimate the expected scatterometric performance of both missions.

  3. Simulation of GNSS reflected signals and estimation of position accuracy in GNSS-challenged environment

    DEFF Research Database (Denmark)

    Jakobsen, Jakob; Jensen, Anna B. O.; Nielsen, Allan Aasbjerg

    2015-01-01

    The paper describes the development and testing of a simulation tool, called QualiSIM. The tool estimates GNSS-based position accuracy based on a simulation of the environment surrounding the GNSS antenna, with a special focus on city-scape environments with large amounts of signal reflections from...

  4. 'Outrunning' the running ear

    African Journals Online (AJOL)

    Chantel

    acute purulent otitis media should be considered when evaluating a patient with a running ear.These are listed in Table I. To outrun the running ear all these facts should be kept in mind when evaluating a patient. HISTORY. Some important questions to ask, are: • Family history. • cystic fibrosis. • allergies — nasal, chest and.

  5. External Otitis (Swimmer's Ear)

    Science.gov (United States)

    ... an otoscope for redness, swelling, and pus. Debris removal, antibiotic ear drops, keeping water out of the ear, and pain relievers are ... cleaning it (using cotton-tipped swabs) or getting water or irritants, such as hair spray or hair dye, in the canal often leads to external otitis. ...

  6. "Swimmer's Ear" (Otitis Externa) Prevention

    Science.gov (United States)

    ... drops. Is there a difference between a childhood middle ear infection and swimmer's ear? Yes. Swimmer’s ear ... WASH-related Emergencies & Outbreaks Water, Sanitation, & Environmentally-related Hygiene Get Email Updates To receive email updates about ...

  7. Satellite Tags- Hawaii EEZ

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Satellite tagging was implemented in 2013. Satellite tagging is conducted using a Dan Inject air rifle and deployment arrows designed by Wildlife Computers. Two...

  8. Donor Tag Game

    Science.gov (United States)

    ... Donor Community > Games > Donor Tag Game Donor Tag Game This feature requires version 6 or later of ... of Needles LGBTQ+ Donors Blood Donor Community SleevesUp Games Facebook Avatars and Badges Banners eCards Make a ...

  9. Cooperative Tagging Center (CTC)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Cooperative Tagging Center (CTC) began as the Cooperative Game Fish Tagging Program (GTP) at Woods Hole Oceanographic Institute (WHOI) in 1954. The GTP was...

  10. Ensemble Time in GNSS - Performance Requirements and Algorithm Tests

    National Research Council Canada - National Science Library

    Suess, Mattgias; Moudrak, Alexandre; Frolova, E

    2007-01-01

    Any Global Navigation Satellite System (GNSS) relies on a highly stable and reliable System Time that has to meet high-performance requirements to enable GNSS services suitable for navigation and timing communities...

  11. Ear Problems in Swimmers

    Directory of Open Access Journals (Sweden)

    Mao-Che Wang

    2005-08-01

    Full Text Available Acute diffuse otitis externa (swimmer's ear, otomycosis, exostoses, traumatic eardrum perforation, middle ear infection, and barotraumas of the inner ear are common problems in swimmers and people engaged in aqua activities. The most common ear problem in swimmers is acute diffuse otitis externa, with Pseudomonas aeruginosa being the most common pathogen. The symptoms are itching, otalgia, otorrhea, and conductive hearing loss. The treatment includes frequent cleansing of the ear canal, pain control, oral or topical medications, acidification of the ear canal, and control of predisposing factors. Swimming in polluted waters and ear-canal cleaning with cotton-tip applicators should be avoided. Exostoses are usually seen in people who swim in cold water and present with symptoms of accumulated debris, otorrhea and conductive hearing loss. The treatment for exostoses is transmeatal surgical removal of the tumors. Traumatic eardrum perforations may occur during water skiing or scuba diving and present with symptoms of hearing loss, otalgia, otorrhea, tinnitus and vertigo. Tympanoplasty might be needed if the perforations do not heal spontaneously. Patients with chronic otitis media with active drainage should avoid swimming, while patients who have undergone mastoidectomy and who have no cavity problems may swim. For children with ventilation tubes, surface swimming is safe in a clean, chlorinated swimming pool. Sudden sensorineural hearing loss and some degree of vertigo may occur after diving because of rupture of the round or oval window membrane.

  12. The Current Status of Research on GNSS-R Remote Sensing Technology in China and Future Development

    Directory of Open Access Journals (Sweden)

    Li Huang

    2013-12-01

    Full Text Available Global Navigation Satellite System (GNSS, has a significant impact on all areas of human activity, not only can provide users with shared global navigation, position and timing information, but also can provide a L-band microwave signal source of long term stability and high temporal-spatial resolution. In recent years, development of the navigation satellite remote sensing applications using GNSS as a external illuminator, it has been forming a new Global Navigation Satellite System METeorology (GNSS/MET, of which Global Navigation Satellite System-Reflection (GNSS-R signals remote sensing technology is rising. It could be considered as a non-cooperative artificial illuminator, bistatic (multi-static radar system, and has the advantages of both passive and active remote sensing. Then it gets more and more people’s attention and favor, and broadening into Atmosphere -ocean and land surface remote sensing fields. However, the address of this technology is very messy at home and abroad, and not able to accurately express its special meaning. This article attempts to give a new term: Exogenous-Aided Remote Sensing (EARS for discussion.

  13. Calibrating coastal GNSS-R instrumentation

    Science.gov (United States)

    Löfgren, Johan; Haas, Rüdiger; Hobiger, Thomas

    2015-04-01

    Since 2011, a GNSS-R (Global Navigation Satellite System - Reflectometry) instrument for local sea level observations is operated at the Onsala Space Observatory (Löfgren et al., 2011). The Onsala Space Observatory is the Swedish geodetic fundamental station, located at the Swedish West Coast, and contributes to the Global Geodetic Observing System (GGOS) by a variety of geodetic and geophysical observations. The Onsala GNSS-R instrumentation consists of two GNSS antennas that are mounted back-to-back on a bar at the coastline extending over the open sea in southward direction. One of the antennas is upward oriented and receives the direct satellite signals, while the other antenna is downward oriented and receives the satellite signals that reflect off the sea surface. The antennas are connected to a commercial GNSS receiver each and data are recorded with sampling rate of up to 20 Hz. Satellite signals of several GNSS are received and are analysed with various different analysis strategies to provide sea level results with different temporal resolution and precision (Larson et al., 2013; Löfgren and Haas, 2014). Since the instrumentation uses GNSS signals, it is possible to derive both local sea level, i.e. relative to the coast, and absolute sea level, i.e. relative to the geocentre as realised by the GNSS. The bar carrying the two antennas can be placed in 10 different vertical positions covering a height difference of 2.5 m between the highest and lowest position. We present results from a calibration campaign of the Onsala GNSS-R instrumentation performed in 2014. During this several weeks long campaign the antennas were placed at different vertical positions for several days at each position. The recorded data are analysed with the different analysis strategies, and the results are compared to the results derived from the co-located tide gauge equipment. References - Löfgren J, Haas R, Scherneck H-G (2011). Three months of local sea-level derived from

  14. Monocular Camera/IMU/GNSS Integration for Ground Vehicle Navigation in Challenging GNSS Environments

    Directory of Open Access Journals (Sweden)

    Dennis Akos

    2012-03-01

    Full Text Available Low-cost MEMS-based IMUs, video cameras and portable GNSS devices are commercially available for automotive applications and some manufacturers have already integrated such facilities into their vehicle systems. GNSS provides positioning, navigation and timing solutions to users worldwide. However, signal attenuation, reflections or blockages may give rise to positioning difficulties. As opposed to GNSS, a generic IMU, which is independent of electromagnetic wave reception, can calculate a high-bandwidth navigation solution, however the output from a self-contained IMU accumulates errors over time. In addition, video cameras also possess great potential as alternate sensors in the navigation community, particularly in challenging GNSS environments and are becoming more common as options in vehicles. Aiming at taking advantage of these existing onboard technologies for ground vehicle navigation in challenging environments, this paper develops an integrated camera/IMU/GNSS system based on the extended Kalman filter (EKF. Our proposed integration architecture is examined using a live dataset collected in an operational traffic environment. The experimental results demonstrate that the proposed integrated system provides accurate estimations and potentially outperforms the tightly coupled GNSS/IMU integration in challenging environments with sparse GNSS observations.

  15. Monocular camera/IMU/GNSS integration for ground vehicle navigation in challenging GNSS environments.

    Science.gov (United States)

    Chu, Tianxing; Guo, Ningyan; Backén, Staffan; Akos, Dennis

    2012-01-01

    Low-cost MEMS-based IMUs, video cameras and portable GNSS devices are commercially available for automotive applications and some manufacturers have already integrated such facilities into their vehicle systems. GNSS provides positioning, navigation and timing solutions to users worldwide. However, signal attenuation, reflections or blockages may give rise to positioning difficulties. As opposed to GNSS, a generic IMU, which is independent of electromagnetic wave reception, can calculate a high-bandwidth navigation solution, however the output from a self-contained IMU accumulates errors over time. In addition, video cameras also possess great potential as alternate sensors in the navigation community, particularly in challenging GNSS environments and are becoming more common as options in vehicles. Aiming at taking advantage of these existing onboard technologies for ground vehicle navigation in challenging environments, this paper develops an integrated camera/IMU/GNSS system based on the extended Kalman filter (EKF). Our proposed integration architecture is examined using a live dataset collected in an operational traffic environment. The experimental results demonstrate that the proposed integrated system provides accurate estimations and potentially outperforms the tightly coupled GNSS/IMU integration in challenging environments with sparse GNSS observations.

  16. Ear Infections - Multiple Languages

    Science.gov (United States)

    ... Ear Infection in Children - 简体中文 (Chinese, Simplified (Mandarin dialect)) Bilingual PDF Health Information Translations Chinese, Traditional (Cantonese dialect) (繁體中文) Expand Section Middle ...

  17. Ear tube insertion

    Science.gov (United States)

    ... mastoiditis) or the brain, or that damages nearby nerves Injury to the ear after sudden changes in ... does not heal after the tube falls out. Most of the time, these problems DO NOT last long. They also ...

  18. Combining the Observations from Different GNSS (Invited)

    Science.gov (United States)

    Dach, R.; Lutz, S.; Schaer, S.; Bock, H.; Jäggi, A.; Meindl, M.; Ostini, L.; Thaller, D.; Steinbach, A.; Beutler, G.; Steigenberger, P.

    2009-12-01

    For a very long time GPS has clearly dominated the use of GNSS measurements for scientific purposes. This picture is changing: we are moving from a GPS-only to a multi-GNSS world. This is, e.g., reflected by changing the meaning of the abbreviation IGS in March 2005 from International GPS to GNSS Service. The current situation can be described as follows: GPS has the leading role in the GNSS because it has provided a very stable satellite constellation over many years. Some of the currently active GPS satellites are nearly 15 years old. These old satellites are expected to be decommissioned within the next years. On the other hand, due to the increasing number of active GLONASS satellites and the improved density of multi-GNSS tracking stations in the IGS network, the quality of the GLONASS orbits has drastically improved during the last years. The European Galileo system is under development: currently two test satellites (GIOVE-A and GIOVE-B) are in orbit. The IOV (in-orbit-validation phase) will start soon. Also the first test satellites for the Chinese Compass system are in space. For the maximum benefit the observations of these GNSS will be processed in a combined multi-GNSS analysis in future. CODE (Center for Orbit Determination in Europe) is a joint venture between the Astronomical Institute of the University Bern (AIUB, Bern, Switzerland), the Federal Office of Topography (swisstopo, Wabern, Switzerland), the Federal Agency for Cartography and Geodesy (BKG, Frankfurt am Main, Germany), and the Institut für Astronomische und Physikalische Geodäsie of the Technische Universität München (IAPG/TUM, Munich, Germany). It acts as one of the global analysis centers of the IGS and has started in May 2003 with a rigorous combined processing of GPS and GLONASS measurements for the final, rapid, and even ultra-rapid product lines. All contributions from CODE to the IGS are in fact multi-GNSS products -- the only exception is the satellite and receiver clock

  19. High accuracy GNSS based navigation in GEO

    Science.gov (United States)

    Capuano, Vincenzo; Shehaj, Endrit; Blunt, Paul; Botteron, Cyril; Farine, Pierre-André

    2017-07-01

    Although significant improvements in efficiency and performance of communication satellites have been achieved in the past decades, it is expected that the demand for new platforms in Geostationary Orbit (GEO) and for the On-Orbit Servicing (OOS) on the existing ones will continue to rise. Indeed, the GEO orbit is used for many applications including direct broadcast as well as communications. At the same time, Global Navigation Satellites System (GNSS), originally designed for land, maritime and air applications, has been successfully used as navigation system in Low Earth Orbit (LEO) and its further utilization for navigation of geosynchronous satellites becomes a viable alternative offering many advantages over present ground based methods. Following our previous studies of GNSS signal characteristics in Medium Earth Orbit (MEO), GEO and beyond, in this research we specifically investigate the processing of different GNSS signals, with the goal to determine the best navigation performance they can provide in a GEO mission. Firstly, a detailed selection among different GNSS signals and different combinations of them is discussed, taking into consideration the L1 and L5 frequency bands, and the GPS and Galileo constellations. Then, the implementation of an Orbital Filter is summarized, which adaptively fuses the GN1SS observations with an accurate orbital forces model. Finally, simulation tests of the navigation performance achievable by processing the selected combination of GNSS signals are carried out. The results obtained show an achievable positioning accuracy of less than one meter. In addition, hardware-in-the-loop tests are presented using a COTS receiver connected to our GNSS Spirent simulator, in order to collect real-time hardware-in-the-loop observations and process them by the proposed navigation module.

  20. High Precision GNSS Guidance for Field Mobile Robots

    Directory of Open Access Journals (Sweden)

    Ladislav Jurišica

    2012-11-01

    Full Text Available In this paper, we discuss GNSS (Global Navigation Satellite System guidance for field mobile robots. Several GNSS systems and receivers, as well as multiple measurement methods and principles of GNSS systems are examined. We focus mainly on sources of errors and investigate diverse approaches for precise measuring and effective use of GNSS systems for real-time robot localization. The main body of the article compares two GNSS receivers and their measurement methods. We design, implement and evaluate several mathematical methods for precise robot localization.

  1. Tagging vs. Controlled Vocabulary

    DEFF Research Database (Denmark)

    Bogers, Toine; Petras, Vivien

    2015-01-01

    elements like core bibliographic data, controlled vocabulary terms, reviews, and tags to the retrieval performance. Our comparison is done using a test collection of over 2 million book records with information elements from Amazon, the British Library, the Library of Congress, and LibraryThing. We find...... that tags and controlled vocabulary terms do not actually outperform each other consistently, but seem to provide complementary contributions: some information needs are best addressed using controlled vocabulary terms whereas other are best addressed using tags....

  2. Tags on healthcare information websites

    DEFF Research Database (Denmark)

    Lykke, Marianne; Ådland, Marit Kristine

    2018-01-01

    This paper explores tags and tagging behaviour on health information websites using an empirical, user-oriented, exploratory case study. Taggers and editors were interviewed about tags and tagging, while taggers solved tasks that included applying tags to a website. This qualitative data...... articles, request information, and value article content. Some of these show that tags are not only not only topical descriptions, but communicative by intent. This result can potentially inform the design of tagging features....

  3. Ionospheric Modeling for Precise GNSS Applications

    NARCIS (Netherlands)

    Memarzadeh, Y.

    2009-01-01

    The main objective of this thesis is to develop a procedure for modeling and predicting ionospheric Total Electron Content (TEC) for high precision differential GNSS applications. As the ionosphere is a highly dynamic medium, we believe that to have a reliable procedure it is necessary to transfer

  4. GNSS ambiguity resolution : Which subset to fix?

    NARCIS (Netherlands)

    Verhagen, A.A.; Teunissen, P.J.G.; Van der Marel, H.; Li, B.

    2011-01-01

    A key issue with GNSS carrier phase ambiguity resolution is that often the full set of ambiguities cannot be fixed fast and reliably. A possible strategy is then to resolve only a subset of ambiguities, one for which the probability of correct fixing, the so-called success rate, is sufficiently

  5. GNSS signal acquisition in harsh urban environments

    NARCIS (Netherlands)

    Wildemeersch, Matthias; Wildemeersch, Matthias; Slump, Cornelis H.; Quek, Tony Q.S.; Rabbachin, Alberto

    2013-01-01

    In urban environment, Global Navigation Satellite System (GNSS) signals are impaired by non-line-of-sight fading conditions and by the presence of potential sources of electromagnetic disturbance. This paper analyzes the impact of the wireless propagation medium and aggregate network interference by

  6. GNSS climatology: A summary of findings from the COST Action ES1206 GNSS4SWEC

    Science.gov (United States)

    Bock, Olivier; Pacione, Rosa

    2017-04-01

    Working Group 3 of COST Action GNSS4SWEC promoted the coordinated development and assessment of GNSS tropospheric products for climate research. More than 50 researchers from 17 institutions participated in the discussions. The activities were organised in five main topics, each of which led to conclusions and recommendations for a proper production and use of GNSS tropospheric products for climate research. 1) GNSS data processing and validation: an inventory was established listing the main existing reprocessed datasets and one of them (IGS repro1) was more specifically assessed and used as a community dataset to demonstrate the capacity of GNSS to retrieve decadal trends and variability in zenith tropospheric delay (ZTD). Several groups performed also processing sensitivity studies producing long term (15 years or more) solutions and testing the impact of various processing parameters (tropospheric models, cutoff angle…) on the accuracy and stability of the retrieved ZTD estimates. 2) Standards and methods for post-processing: (i) elaborate screening methods have been developed and tested for the detection of outliers in ZTD data; (ii) ZTD to IWV conversion methods and auxiliary datasets have been reviewed and assessed; (iii) the homogeneity of long ZTD and IWV time series has been investigated. Standardised procedures were proposed for first two points. Inhomogeneities have been identified in all reprocessed GNSS datasets which are due to equipment changes or changes in the measurement conditions. Significant activity is on-going on the development of statistical homogenisation techniques that match the GNSS data characteristics. 3) IWV validations: new intercomparisons of GNSS IWV estimates to IWV retrieved from other observational techniques (radiosondes, microwave radiometers, VLBI, DORIS…) have been encouraged to enhance the results of the past and contribute to a better evaluation of inter-technique biases and absolute accuracy of the different IWV

  7. Middle Ear Infections and Ear Tube Surgery (For Parents)

    Science.gov (United States)

    ... ears.) Infection Bacteria or viruses can enter the middle ear through the eustachian tube and cause an infection — this often happens when a child has had a cold or other respiratory infection. ...

  8. Analysis of Tide Variation Monitored by GNSS-MR

    Directory of Open Access Journals (Sweden)

    ZHANG Shuangcheng

    2016-09-01

    Full Text Available Precise monitoring of tide variation is the most of issues in the fields of Global Sea-level Observation System, ocean circulation and global climate change research. With the deepening research and rapid application of GNSS, GNSS-MR based on multipath has gradually become a new means of remote sensing for ground environment (vegetation, soil moisture, snow depth, sea level, volcano and so on with geodetic GNSS station. By analyzing the characteristics of the onshore GNSS SNR data which is caused by multipath, the inversion principle of GNSS-MR technology based on the SNR data to detect tide variation is given in this paper. The onshore GNSS station of SC02 which is located in Friday Harbor, Washington state of United States, are used to retrieve tide variation. The retrieval result is consistent with the tide gauge which is only 359m to the GNSS station. The bias is about 10cm, and the correlation coefficient is better than 0.98. Preliminary results show that GNSS-MR technology based on onshore CORS station to some extent could be real-time and continuously used to monitor the tide variation. What's more, onshore GNSS stations could be a powerful supplement for tide gauge and be used to extend GNSS application in marine remote sensing field.

  9. QUAD TAG MODULE

    International Nuclear Information System (INIS)

    Shiino, K.; Maruyama, K.

    1981-08-01

    Electronic circuits called QUAD TAG MODULE were developed and constructed, which were of exclusive use for signals from scintillation counter hodoscope of the photon tagging system. The circuit has functions of amplifiers, discriminators, and strobed coincidences in one NIM module. A description on functions and specifications of the module is given. (author)

  10. PIT Tagging Anurans

    Science.gov (United States)

    McCreary, Brome

    2008-01-01

    The following video demonstrates a procedure to insert a passive integrated transponder (PIT) tag under the skin of an anuran (frog or toad) for research and monitoring purposes. Typically, a 12.5 mm tag (0.5 in.) is used to uniquely identify individual anurans as smal as 40 mm (1.6 in.) in length from snout to vent. Smaller tags are also available and allow smaller anurans to be tagged. The procedure does not differ for other sizes of tages or other sizes of anurans. Anyone using this procedure should ensure that the tag is small enough to fit easily behind the sacral hump of the anuran, as shown in this video.

  11. Ear, Hearing and Speech

    DEFF Research Database (Denmark)

    Poulsen, Torben

    2000-01-01

    An introduction is given to the the anatomy and the function of the ear, basic psychoacoustic matters (hearing threshold, loudness, masking), the speech signal and speech intelligibility. The lecture note is written for the course: Fundamentals of Acoustics and Noise Control (51001)...

  12. From Ear to Brain

    Science.gov (United States)

    Kimura, Doreen

    2011-01-01

    In this paper Doreen Kimura gives a personal history of the "right-ear effect" in dichotic listening. The focus is on the early ground-breaking papers, describing how she did the first dichotic listening studies relating the effects to brain asymmetry. The paper also gives a description of the visual half-field technique for lateralized stimulus…

  13. Middle Ear Infections

    Science.gov (United States)

    ... to develop a serious illness. What if a child with a middle ear infection is in great pain and discomfort? The mainstay of pain management for AOM is medications such as acetominophen ... before the child's bedtime. Fortunately, by 24 hours about 60 percent ...

  14. Middle ear implants

    Directory of Open Access Journals (Sweden)

    K S Gangadhara Somayaji

    2013-01-01

    Full Text Available Hearing loss is becoming more common in the society living in cities with lot of background noise around, and frequent use of gadgets like mobile phones, MP3s, and IPods are adding to the problem. The loss may involve the conductive or perceptive pathway. Majority of the patients with conductive hearing loss will revert back to normal hearing levels with medical and/or surgical treatment. However, in sensorineural hearing loss, many factors are involved in the management. Though traditionally hearing aids in various forms are the most commonly used modality in managing these patients, there are some drawbacks associated with them. Implantable middle ear amplifiers represent the most recent breakthrough in the management of hearing loss. Middle ear implants are surgically implanted electronic devices that aim to correct hearing loss by stimulating the ossicular chain or middle ear. Of late, they are also being used in the management of congenital conductive hearing loss and certain cases of chronic otitis media with residual hearing loss. The article aims to provide general information about the technology, indications and contraindications, selection of candidates, available systems, and advantages of middle ear implants. (MEI

  15. Middle ear effusion

    African Journals Online (AJOL)

    NJSR

    Abstract. Carcinoma of the breast can metastasise to many organs. Metastasis to the temporal bone is rare and even when it does, it would usually spread to other parts of the body. This is a report of isolated metastasis to the temporal bone with middle ear effusion. Key words: Carcinoma, breast, metastasis, temporal bone, ...

  16. Occurrence of Different External Ear Deformities in Monozygotic Twins: Report of 2 Cases

    Directory of Open Access Journals (Sweden)

    Jin-Tian Hu, MD

    2014-09-01

    Full Text Available Summary: Microtia is a spectrum of congenital deformities, which varies from barely discernable to anotia. Twinning is a well-known risk factor for congenital defects including external ear deformities. Monozygotic twins usually show identical appearances as well as congenital malformations. In special conditions as ear deformities, “mirror-image” may also occur. We report 2 cases of monozygotic twins with different ear deformities. The 8-year-old propositus with lobule type microtia and her identical female twin presented with facial symmetry. Patient A had sausage-type right microtia with absence of external auditory canal. The left external ear showed normal appearance. Patient B presented with left-sided preauricular skin tag and right-sided malformation of tragus with skin tag combined with hyperplasia of underlying cartilage. A granule-size skin tag was also noticed at crus of right helix. A 7-year-old male patient with right-sided conchal type microtia presented to an ear reconstruction center. The patient’s mother showed normal auricular appearance. Her monozygotic twin sister, whose son and daughter had normal ear appearance, was diagnosed with a leftsided lobule type microtia.

  17. Calibration of Magnetometers with GNSS Receivers and Magnetometer-Aided GNSS Ambiguity Fixing.

    Science.gov (United States)

    Henkel, Patrick

    2017-06-08

    Magnetometers provide compass information, and are widely used for navigation, orientation and alignment of objects. As magnetometers are affected by sensor biases and eventually by systematic distortions of the Earth magnetic field, a calibration is needed. In this paper, a method for calibration of magnetometers with three Global Navigation Satellite System (GNSS) receivers is presented. We perform a least-squares estimation of the magnetic flux and sensor biases using GNSS-based attitude information. The attitude is obtained from the relative positions between the GNSS receivers in the North-East-Down coordinate frame and prior knowledge of these relative positions in the platform's coordinate frame. The relative positions and integer ambiguities of the periodic carrier phase measurements are determined with an integer least-squares estimation using an integer decorrelation and sequential tree search. Prior knowledge on the relative positions is used to increase the success rate of ambiguity fixing. We have validated the proposed method with low-cost magnetometers and GNSS receivers on a vehicle in a test drive. The calibration enabled a consistent heading determination with an accuracy of five degrees. This precise magnetometer-based attitude information allows an instantaneous GNSS integer ambiguity fixing.

  18. TriG: Next Generation Scalable Spaceborne GNSS Receiver

    Science.gov (United States)

    Tien, Jeffrey Y.; Okihiro, Brian Bachman; Esterhuizen, Stephan X.; Franklin, Garth W.; Meehan, Thomas K.; Munson, Timothy N.; Robison, David E.; Turbiner, Dmitry; Young, Lawrence E.

    2012-01-01

    TriG is the next generation NASA scalable space GNSS Science Receiver. It will track all GNSS and additional signals (i.e. GPS, GLONASS, Galileo, Compass and Doris). Scalable 3U architecture and fully software and firmware recofigurable, enabling optimization to meet specific mission requirements. TriG GNSS EM is currently undergoing testing and is expected to complete full performance testing later this year.

  19. Flavour Tagging at LHCb

    CERN Document Server

    Grabalosa Gandara, M

    2009-01-01

    To do precise CP violation measurements, the most possible accurate knowledge of the flavour at production of the reconstructed B meson is required. This poster summarizes the flavour tagging performances for the LHCb experiment. We use same side an opposite side algorithms to establish wheter the meson contained a b or a b\\bar quark. The final decision is obtained through a combination of several methods. The use of control channels, decays to a flavour specific final state, will allow to determine the wrong tag fraction \\omega (the probability of a tag to be wrong), which can be used as input for the determination of CKM unitary triangle angles.

  20. Parallel post-processing solution for GNSS-R instrument

    OpenAIRE

    Guo, Yi,

    2012-01-01

    Descripció del recurs: el 01 setembre 2012 Las señales de banda trasmitidas por los sistemas de navegación global por satélite (GNSS, Global Navigation Satellites Systems) permiten averiguar algunas de las propiedades geof'ısicas de la Tierra al reflejarse en su superficie. Este concepto se llama reflectometría GNSS (GNSS-R) o sistema de interferometría y reflectometría pasivo (PARIS, Passive Reflectometry and Interferometry System). Una serie de receptores GNSS-R especializados se encarga...

  1. Deep Coupled Integration of CSAC and GNSS for Robust PNT.

    Science.gov (United States)

    Ma, Lin; You, Zheng; Li, Bin; Zhou, Bin; Han, Runqi

    2015-09-11

    Global navigation satellite systems (GNSS) are the most widely used positioning, navigation, and timing (PNT) technology. However, a GNSS cannot provide effective PNT services in physical blocks, such as in a natural canyon, canyon city, underground, underwater, and indoors. With the development of micro-electromechanical system (MEMS) technology, the chip scale atomic clock (CSAC) gradually matures, and performance is constantly improved. A deep coupled integration of CSAC and GNSS is explored in this thesis to enhance PNT robustness. "Clock coasting" of CSAC provides time synchronized with GNSS and optimizes navigation equations. However, errors of clock coasting increase over time and can be corrected by GNSS time, which is stable but noisy. In this paper, weighted linear optimal estimation algorithm is used for CSAC-aided GNSS, while Kalman filter is used for GNSS-corrected CSAC. Simulations of the model are conducted, and field tests are carried out. Dilution of precision can be improved by integration. Integration is more accurate than traditional GNSS. When only three satellites are visible, the integration still works, whereas the traditional method fails. The deep coupled integration of CSAC and GNSS can improve the accuracy, reliability, and availability of PNT.

  2. Tagged Vector Contour (TVC)

    Data.gov (United States)

    Kansas Data Access and Support Center — The Kansas Tagged Vector Contour (TVC) dataset consists of digitized contours from the 7.5 minute topographic quadrangle maps. Coverage for the state is incomplete....

  3. An Overview of GNSS Remote Sensing

    Science.gov (United States)

    2014-08-27

    vital information for studies of deep-ocean circulation and boundary currents, the mid-ocean gyres, tsunamis and ocean currents on synoptic to global...tracks associated with four GPS satellites, colourised by reflected signal power. The picture was generated by Google Earth and GPS Visualizer. Yu et al...not from satellite plat- forms. There are no geodetic services producing GNSS remote sensing products on a continuous, synoptic basis. From the IAG’s

  4. Simulation Tool for GNSS Ocean Surface Reflections

    OpenAIRE

    Høeg, Per; von Benzon, Hans-Henrik; Durgonics, Tibor

    2015-01-01

    GNSS coherent and incoherent reflected signals have the potential of deriving large scale parameters of ocean surfaces, as barotropic variability, eddy currents and fronts, Rossby waves, coastal upwelling, mean ocean surfaceheights, and patterns of the general ocean circulation. In the reflection zone the measurements may deriveparameters as sea surface roughness, winds, waves, heights and tilts from the spectral measurements. Previous measurements from the top of mountains and airplanes have...

  5. GNSS observations in the Gabriela locality

    Czech Academy of Sciences Publication Activity Database

    Doležalová, Hana; Kajzar, Vlastimil; Souček, Kamil; Staš, Lubomír

    2012-01-01

    Roč. 19, č. 1 (2012), s. 13-18 ISSN 1803-1447 R&D Projects: GA MŠk ED2.1.00/03.0082; GA MŠk(CZ) ED1.1.00/02.0070 Institutional support: RVO:68145535 Keywords : undermining * GNSS * surface changes Subject RIV: DH - Mining, incl. Coal Mining http://caag.cz/egrse/2012-1/02_dolezalova-r.pdf

  6. Spatial Characterization of GNSS Multipath Channels

    Directory of Open Access Journals (Sweden)

    Hatef Keshvadi

    2012-01-01

    Full Text Available There is a growing interest in detecting and processing Global Navigation Satellite System (GNSS signals in indoors and urban canyons by handheld devices. To overcome the signal attenuation problem in such adverse fading environments, long coherent integration is normally used. Moving the antenna arbitrarily while collecting signals is generally avoided as it temporally decorrelates the signals and limits the coherent integration gain. This decorrelation is a function of the antenna displacement and geometry of reflectors and angle of arrival of the received signal. Hence, to have an optimum receiver processing strategy it is crucial to characterize the multipath fading channel parameters. Herein, Angle of Arrival (AoA and Angle Spread (AS along with signal spatial correlation coefficient and fading intensity in GNSS multipath indoor channels are defined and quantified theoretically and practically. A synthetic uniform circular array utilizing a right-hand circular polarized (RHCP antenna has been used to measure the spatial characteristics of indoor GNSS fading channels. Furthermore, rotating effect of a circular polarized antenna on the synthetic array processing and AoA estimation has been characterized. The performance of the beamforming technique via array gain is also assessed to explore the advantages and limitations of beamforming in fading conditions.

  7. Determining inter-system bias of GNSS signals with narrowly spaced frequencies for GNSS positioning

    Science.gov (United States)

    Tian, Yumiao; Liu, Zhizhao; Ge, Maorong; Neitzel, Frank

    2017-12-01

    Relative positioning using multi-GNSS (global navigation satellite systems) can improve accuracy, reliability, and availability compared to the use of a single constellation system. Intra-system double-difference (DD) ambiguities (ISDDAs) refer to the DD ambiguities between satellites of a single constellation system and can be fixed to an integer to derive the precise fixed solution. Inter-system ambiguities, which denote the DD ambiguities between different constellation systems, can also be fixed to integers on overlapping frequencies, once the inter-system bias (ISB) is removed. Compared with fixing ISDDAs, fixing both integer intra- and inter-system DD ambiguities (IIDDAs) means an increase of positioning precision through an integration of multiple GNSS constellations. Previously, researchers have studied IIDDA fixing with systems of the same frequencies, but not with systems of different frequencies. Integer IIDDAs can be determined from single-difference (SD) ambiguities, even if the frequencies of multi-GNSS signals used in the positioning are different. In this study, we investigated IIDDA fixing for multi-GNSS signals of narrowly spaced frequencies. First, the inter-system DD models of multi-GNSS signals of different frequencies are introduced, and the strategy for compensating for ISB is presented. The ISB is decomposed into three parts: 1) a float approximate ISB number that can be considered equal to the ISB of code pseudorange observations and thus can be estimated through single point positioning (SPP); 2) a number that is a multiple of the GNSS signal wavelength; and 3) a fractional ISB part, with a magnitude smaller than a single wavelength. Then, the relationship between intra- and inter-system DD ambiguity RATIO values and ISB was investigated by integrating GPS L1 and GLONASS L1 signals. In our numerical analyses with short baselines, the ISB parameter and IIDDA were successfully fixed, even if the number of observed satellites in each system

  8. ATLAS Boosted Objects tagging performance

    CERN Document Server

    Ferreira de Lima, D E; The ATLAS collaboration

    2014-01-01

    In the session on the performance of jet substructure reconstruction and boosted object tagging. This first contribution focuses on boosted object tagging performance. Material includes the shower deconstruction CONF note (missed BOOST2013, public), the Boosted boson tagging note (ATL-PHYS-PUB-2014-004, public since April). New papers on W/Z dsicrimination or top tagging are unlikely.

  9. Facets: Ersatz, Resource and Tag

    Science.gov (United States)

    Frické, Martin H.

    2013-01-01

    Introduction: Faceted classification appears to be of utmost importance. Ersatz facets, resource faceting and tag faceting: The distinctions are drawn between facets and ersatz facets, and between faceted resources and faceted tags. Single tag resource faceting and multiple tag information object faceting: The basic features are explored of single…

  10. GNSS-Reflectometry based water level monitoring

    Science.gov (United States)

    Beckheinrich, Jamila; Schön, Steffen; Beyerle, Georg; Apel, Heiko; Semmling, Maximilian; Wickert, Jens

    2013-04-01

    Due to climate changing conditions severe changes in the Mekong delta in Vietnam have been recorded in the last years. The goal of the German Vietnamese WISDOM (Water-related Information system for the Sustainable Development Of the Mekong Delta) project is to build an information system to support and assist the decision makers, planners and authorities for an optimized water and land management. One of WISDOM's tasks is the flood monitoring of the Mekong delta. Earth reflected L-band signals from the Global Navigation Satellite System show a high reflectivity on water and ice surfaces or on wet soil so that GNSS-Reflectometry (GNSS-R) could contribute to monitor the water level in the main streams of the Mekong delta complementary to already existing monitoring networks. In principle, two different GNSS-R methods exist: the code- and the phase-based one. As the latter being more accurate, a new generation of GORS (GNSS Occultation, Reflectometry and Scatterometry) JAVAD DELTA GNSS receiver has been developed with the aim to extract precise phase observations. In a two week lasting measurement campaign, the receiver has been tested and several reflection events at the 150-200 m wide Can Tho river in Vietnam have been recorded. To analyze the geometrical impact on the quantity and quality of the reflection traces two different antennas height were tested. To track separately the direct and the reflected signal, two antennas were used. To derive an average height of the water level, for a 15 min observation interval, a phase model has been developed. Combined with the coherent observations, the minimum slope has been calculated based on the Least- Squares method. As cycle slips and outliers will impair the results, a preprocessing of the data has been performed. A cycle slip detection strategy that allows for automatic detection, identification and correction is proposed. To identify outliers, the data snooping method developed by Baarda 1968 is used. In this

  11. Hourly Updated GNSS Orbit and Clock

    Science.gov (United States)

    Song, S.; Xue, J.

    2016-12-01

    With the development of the performance of GNSS, the hourly updated orbit and clock of GNSS are paid much more attention and used by more and more users because of the timeliness and high accuracy. The hourly GNSS orbit and clock are produced routinely in Shanghai Analysis Center(AC) of the International GNSS Monitoring and Assessment Service (iGMAS).In this article, the accuracy of hourly and 6-hourly updated ultra-rapid GPS,GLONASS,GALILEO,BDS orbit and clock (SHU1 and SHU6) are analyzed relative to the final production in detail. The analysis show that, in calculation session, there's no much difference between the mean SHU1 and SHU6 RMS and STD for GNSS orbit and clock. However, for BDS clock in prediction session, the RMS and STD of BDS SHU1 are 2.6ns and 0.5ns respectively, the RMS of BDS SHU6 increase from 2.7ns to 4.5ns from the 1st to the 6th hour prediction session, but there's no much changes of STD. For GPS clock in prediction session, the RMS and STD of GPS SHU1 is quite stable with 0.5ns and 0.2ns.The RMS of GPS SHU6 clock increase from 0.6ns to 1.0ns from the 1st to the 6th hour, but STD is stable at about 0.2ns.For the orbit in calculate session, the RMS of BDS SHU1 is a little less than that of SHU6,the RMS of GPS SHU1 and SHU6 orbit are approximately at the same level. In prediction session, the RMS of IGSO/MEO for BDS SHU1 is relative stable, but the RMS of SHU6 1st-6th hour prediction session increase from about 26.5cm to 32.7cm. The RMS of GPS SHU1 orbit's prediction session is about 3.4cm,but which increase from 3.3cm to 4.3cm for GPS SHU6 1st-6th hour prediction session.The comparison of GLONASS and GALILEO orbit and clock also will be described.The results show that the hourly update is more important for BDS at this stage.Moreover,some problems appearing in satellites and stations can be found earlier by 1 hourly updated frequency.

  12. Ear recognition: a complete system

    Science.gov (United States)

    Abaza, Ayman; Harrison, Mary Ann F.

    2013-05-01

    Ear Recognition has recently received significant attention in the literature. Even though current ear recognition systems have reached a certain level of maturity, their success is still limited. This paper presents an efficient complete ear-based biometric system that can process five frames/sec; Hence it can be used for surveillance applications. The ear detection is achieved using Haar features arranged in a cascaded Adaboost classifier. The feature extraction is based on dividing the ear image into several blocks from which Local Binary Pattern feature distributions are extracted. These feature distributions are then fused at the feature level to represent the original ear texture in the classification stage. The contribution of this paper is three fold: (i) Applying a new technique for ear feature extraction, and studying various optimization parameters for that technique; (ii) Presenting a practical ear recognition system and a detailed analysis about error propagation in that system; (iii) Studying the occlusion effect of several ear parts. Detailed experiments show that the proposed ear recognition system achieved better performance (94:34%) compared to other shape-based systems as Scale-invariant feature transform (67:92%). The proposed approach can also handle efficiently hair occlusion. Experimental results show that the proposed system can achieve about (78%) rank-1 identification, even in presence of 60% occlusion.

  13. Assessment of local GNSS baselines at co-location sites

    Science.gov (United States)

    Herrera Pinzón, Iván; Rothacher, Markus

    2018-01-01

    As one of the major contributors to the realisation of the International Terrestrial Reference System (ITRS), the Global Navigation Satellite Systems (GNSS) are prone to suffer from irregularities and discontinuities in time series. While often associated with hardware/software changes and the influence of the local environment, these discrepancies constitute a major threat for ITRS realisations. Co-located GNSS at fundamental sites, with two or more available instruments, provide the opportunity to mitigate their influence while improving the accuracy of estimated positions by examining data breaks, local biases, deformations, time-dependent variations and the comparison of GNSS baselines with existing local tie measurements. With the use of co-located GNSS data from a subset sites of the International GNSS Service network, this paper discusses a global multi-year analysis with the aim of delivering homogeneous time series of coordinates to analyse system-specific error sources in the local baselines. Results based on the comparison of different GNSS-based solutions with the local survey ties show discrepancies of up to 10 mm despite GNSS coordinate repeatabilities at the sub-mm level. The discrepancies are especially large for the solutions using the ionosphere-free linear combination and estimating tropospheric zenith delays, thus corresponding to the processing strategy used for global solutions. Snow on the antennas causes further problems and seasonal variations of the station coordinates. These demonstrate the need for a permanent high-quality monitoring of the effects present in the short GNSS baselines at fundamental sites.

  14. Integer least-squares theory for the GNSS compass

    NARCIS (Netherlands)

    Teunissen, P.J.G.

    2010-01-01

    Global navigation satellite system (GNSS) carrier phase integer ambiguity resolution is the key to highprecision positioning and attitude determination. In this contribution, we develop new integer least-squares (ILS) theory for the GNSS compass model, together with efficient integer search

  15. Accounting for tagging-to-harvest mortality in a Brownie tag-recovery model by incorporating radio-telemetry data

    Science.gov (United States)

    Buderman, Frances E.; Diefenbach, Duane R.; Casalena, Mary Jo; Rosenberry, Christopher S.; Wallingford, Bret D.

    2014-01-01

    The Brownie tag-recovery model is useful for estimating harvest rates but assumes all tagged individuals survive to the first hunting season; otherwise, mortality between time of tagging and the hunting season will cause the Brownie estimator to be negatively biased. Alternatively, fitting animals with radio transmitters can be used to accurately estimate harvest rate but may be more costly. We developed a joint model to estimate harvest and annual survival rates that combines known-fate data from animals fitted with transmitters to estimate the probability of surviving the period from capture to the first hunting season, and data from reward-tagged animals in a Brownie tag-recovery model. We evaluated bias and precision of the joint estimator, and how to optimally allocate effort between animals fitted with radio transmitters and inexpensive ear tags or leg bands. Tagging-to-harvest survival rates from >20 individuals with radio transmitters combined with 50–100 reward tags resulted in an unbiased and precise estimator of harvest rates. In addition, the joint model can test whether transmitters affect an individual's probability of being harvested. We illustrate application of the model using data from wild turkey, Meleagris gallapavo,to estimate harvest rates, and data from white-tailed deer, Odocoileus virginianus, to evaluate whether the presence of a visible radio transmitter is related to the probability of a deer being harvested. The joint known-fate tag-recovery model eliminates the requirement to capture and mark animals immediately prior to the hunting season to obtain accurate and precise estimates of harvest rate. In addition, the joint model can assess whether marking animals with radio transmitters affects the individual's probability of being harvested, caused by hunter selectivity or changes in a marked animal's behavior.

  16. A comparison of tagging methods and their tagging space.

    Science.gov (United States)

    Ke, Xiayi; Miretti, Marcos M; Broxholme, John; Hunt, Sarah; Beck, Stephan; Bentley, David R; Deloukas, Panos; Cardon, Lon R

    2005-09-15

    Single-nucleotide polymorphism (SNP) tagging is widely used as a way of saving genotyping costs in association studies. A number of different tagging methods have been developed to reduce the number of markers to be genotyped while maintaining power for detecting effects on non-assayed SNPs. How the different methods perform in different settings, the degree to which they overlap and share common tags and how they differ are important questions. We investigated these questions by comparing three widely used tagging methods/algorithms--one haplotype r2-based method, one pair-wise r2-based method and one method which was based on haplotype diversity but focused on major haplotypes. Tagging efficiency was defined as the number of genotyped markers divided by the number of tagging SNPs. Tagging effectiveness was defined as the proportion of un-genotyped or 'hidden' SNPs being detected (having a pair-wise or haplotype r2 with a set of tagging SNPs over a threshold, e.g. haplotype r2> or =0.80). The ENCODE regions genotyped on the HapMap CEPH individuals were examined in this study. Tagging effectiveness was generally poor for rare SNPs than for common SNPs, for all three tagging methods. Inclusion of rare SNPs into initial HapMap scheme could enhance the performance of tags on rare hidden SNPs at the expense of increased genotyping cost. At a moderate tagging efficiency, more than 90% of hidden SNPs detected by tagging SNPs selected by one method were also detected by tagging SNPs selected by another method, and this figure could be increased to 100% if tagging efficiency was allowed to drop. These results indicate that the tagging space is highly concordant between different tagging methods, despite the fact that they often involve different sets of tagging SNPs.

  17. [Endoscopy of the middle ear].

    Science.gov (United States)

    Ayache, Stéphane

    2010-12-20

    The otoscopy is a major point in a daily practice. The otoscope is usually used. In an ENT practice, the microscope is the main instrument but presents limits. The use of rigid endoscopes allows to refine considerably this otoscopy. In ear surgery, the endoscopy of the middle ear for ear chronic diseases has evolved, from an additional tool to the microscope towards an exclusive surgical procedure with its own indications, advantages and limits.

  18. Global GNSS processing based on the raw observation approach

    Science.gov (United States)

    Strasser, Sebastian; Zehentner, Norbert; Mayer-Gürr, Torsten

    2017-04-01

    Many global navigation satellite system (GNSS) applications, e.g. Precise Point Positioning (PPP), require high-quality GNSS products, such as precise GNSS satellite orbits and clocks. These products are routinely determined by analysis centers of the International GNSS Service (IGS). The current processing methods of the analysis centers make use of the ionosphere-free linear combination to reduce the ionospheric influence. Some of the analysis centers also form observation differences, in general double-differences, to eliminate several additional error sources. The raw observation approach is a new GNSS processing approach that was developed at Graz University of Technology for kinematic orbit determination of low Earth orbit (LEO) satellites and subsequently adapted to global GNSS processing in general. This new approach offers some benefits compared to well-established approaches, such as a straightforward incorporation of new observables due to the avoidance of observation differences and linear combinations. This becomes especially important in view of the changing GNSS landscape with two new systems, the European system Galileo and the Chinese system BeiDou, currently in deployment. GNSS products generated at Graz University of Technology using the raw observation approach currently comprise precise GNSS satellite orbits and clocks, station positions and clocks, code and phase biases, and Earth rotation parameters. To evaluate the new approach, products generated using the Global Positioning System (GPS) constellation and observations from the global IGS station network are compared to those of the IGS analysis centers. The comparisons show that the products generated at Graz University of Technology are on a similar level of quality to the products determined by the IGS analysis centers. This confirms that the raw observation approach is applicable to global GNSS processing. Some areas requiring further work have been identified, enabling future

  19. Tropospheric Delay from VLBI and GNSS Measurements

    Science.gov (United States)

    Gubanov, V. S.

    2018-02-01

    Using an updated version of the QUASAR software package developed at the Institute of Applied Astronomy of the Russian Academy of Sciences, we have processed the VLBI observations within the international CONT14 program (May 6-20, 2014), in which a global network of 17 stations was involved (a total of 250 000 observations). The package update concerned the optimization of data structure and the refinement of stochastic models for the random variations in wet tropospheric delay and atomic clock difference. The main goal of this paper is to compare the VLBI determinations of the tropospheric delay with its independent determinations using global navigation satellite systems (GNSS). We show that both these determinations agree well between themselves only in the case of a global analysis of the VLBI observations, where the VLBI station coordinates are also refined, along with the tropospheric delay and the clock synchronization and Earth orientation parameters. If, alternatively, the station coordinates are insufficiently accurate and are not refined from VLBI observations, then it is appropriate not to determine the tropospheric delay from these observations, but to take it from the publicly accessible independent GNSS data. However, this requires that the VLBI and GNSS techniques operate simultaneously at a common observing site. We have established the shortcomings of the universally accepted method of stabilizing the global solution associated with the absence of a criterion for choosing reference stations and radio sources. Two ways of their elimination are proposed: (i) introducing a coordinated list of weight factors for the errors in the coordinates of such stations and sources into the stabilization algorithm and (ii) adopting a coordinated list of stations and sources the refinement of whose coordinates is not required at all for a certain time.

  20. Multi-GNSS Opportunities and Challenges

    Science.gov (United States)

    Al-Shaery, A.; Zhang, S.; Lim, S.; Rizos, C.

    2012-04-01

    The multi-GNSS era has began attracting more attention with the declaration of full operational capability of GLONASS , with a 24 satellites being set to 'healthy' on December 8th 2011 (IAC, 2011). This means that GPS is no longer the only GNSS that provides global positioning coverage. This status brings benefits for GNSS users in areas (e.g. 'urban canyon' environments or in deep open cut mines) where the number of visible satellites is limited because of shadowing effects. In such areas adding more functioning satellites, which is one of the aiding solutions, becomes easier, at no extra cost. The inclusion of GLONASS observations in positioning solutions will increase the available number of satellites and thus positioning accuracy may improve as a result of enhanced overall satellite geometry. Such an aiding solution is increasingly attractive due to the successful revitalisation of GLONASS. Another motivation is the availability of improved GLONASS orbits from the IGS and individual analysis centres of the IGS. The increasing availability of receivers with GPS/GLONASS tracking capability on the market is an additional motive. Consequently, most networks of continuously operating reference stations (CORS) are now equipped with receivers that can track both GPS and GLONASS satellite signals, and therefore network-based positioning with combined GPS and GLONASS observations is possible. However, adding GLONASS observations to GPS is not a straight forward process. This is attributable to a few system differences in reference frames for time and coordinates, and in signal structures. The first two differences are easy to deal with using well-defined conversion and transformation parameters (El-Mowafy, 2001). However, signal structure differences have some implications. The mathematical modelling of combined GPS/GLONASS observations is not performed as in the case of GPS-alone. Special care should be paid to such integration. Not only is the software part affected

  1. Tagging behaviour with support from controlled vocabulary

    DEFF Research Database (Denmark)

    Lykke, Marianne; Høj, Anne Lyhne; Madsen, Line Nørgaard

    2011-01-01

    The paper investigates how knowledge structures from a controlled vocabulary affect tagging. The study is a comparative analysis of tags assigned in two tagging systems, a simple tagging system (control system) that provides suggestions from two tag clouds (all users tags and my tags) and an enha...

  2. The use of external electronic tags on fish: an evaluation of tag retention and tagging effects

    DEFF Research Database (Denmark)

    Jepsen, Niels; Thorstad, Eva B.; Havn, Torgeir

    2015-01-01

    publications, reporting effects of external tagging for 80 different fish species, which constitute the main basis for this review. External attachment holds certain benefits compared to other tagging methods, for example, speed of application, and it may be the only option for fishes with a body shape...... unsuitable for surgical implantation, or when using tags with sensors recording the external environment. The most commonly reported problems with external tags are tissue damage, premature tag loss, and decreased swimming capacity, but the effects are highly context dependent and species specific. Reduced...... growth and survival have also been recorded, but direct mortality caused by external tagging seems rare. Most of the studies reviewed evaluate tag retention, survival, and tissue reactions. There is a general need for more research on the effects of external tagging of fish with electronic tags...

  3. TagPad

    DEFF Research Database (Denmark)

    Bornoe, Nis; Barkhuus, Louise

    2013-01-01

    The area of cyberinfrastructures has looked extensively at research within the natural sciences, however, the social sciences have been largely overlooked in terms of novel data collection and analysis systems. We developed a probe tool, TagPad, to look at the process for social science data...

  4. Ontologies and tag-statistics

    International Nuclear Information System (INIS)

    Tibély, Gergely; Vicsek, Tamás; Pollner, Péter; Palla, Gergely

    2012-01-01

    Due to the increasing popularity of collaborative tagging systems, the research on tagged networks, hypergraphs, ontologies, folksonomies and other related concepts is becoming an important interdisciplinary area with great potential and relevance for practical applications. In most collaborative tagging systems the tagging by the users is completely ‘flat’, while in some cases they are allowed to define a shallow hierarchy for their own tags. However, usually no overall hierarchical organization of the tags is given, and one of the interesting challenges of this area is to provide an algorithm generating the ontology of the tags from the available data. In contrast, there are also other types of tagged networks available for research, where the tags are already organized into a directed acyclic graph (DAG), encapsulating the ‘is a sub-category of’ type of hierarchy between each other. In this paper, we study how this DAG affects the statistical distribution of tags on the nodes marked by the tags in various real networks. The motivation for this research was the fact that understanding the tagging based on a known hierarchy can help in revealing the hidden hierarchy of tags in collaborative tagging systems. We analyse the relation between the tag-frequency and the position of the tag in the DAG in two large sub-networks of the English Wikipedia and a protein-protein interaction network. We also study the tag co-occurrence statistics by introducing a two-dimensional (2D) tag-distance distribution preserving both the difference in the levels and the absolute distance in the DAG for the co-occurring pairs of tags. Our most interesting finding is that the local relevance of tags in the DAG (i.e. their rank or significance as characterized by, e.g., the length of the branches starting from them) is much more important than their global distance from the root. Furthermore, we also introduce a simple tagging model based on random walks on the DAG, capable of

  5. Ontologies and tag-statistics

    Science.gov (United States)

    Tibély, Gergely; Pollner, Péter; Vicsek, Tamás; Palla, Gergely

    2012-05-01

    Due to the increasing popularity of collaborative tagging systems, the research on tagged networks, hypergraphs, ontologies, folksonomies and other related concepts is becoming an important interdisciplinary area with great potential and relevance for practical applications. In most collaborative tagging systems the tagging by the users is completely ‘flat’, while in some cases they are allowed to define a shallow hierarchy for their own tags. However, usually no overall hierarchical organization of the tags is given, and one of the interesting challenges of this area is to provide an algorithm generating the ontology of the tags from the available data. In contrast, there are also other types of tagged networks available for research, where the tags are already organized into a directed acyclic graph (DAG), encapsulating the ‘is a sub-category of’ type of hierarchy between each other. In this paper, we study how this DAG affects the statistical distribution of tags on the nodes marked by the tags in various real networks. The motivation for this research was the fact that understanding the tagging based on a known hierarchy can help in revealing the hidden hierarchy of tags in collaborative tagging systems. We analyse the relation between the tag-frequency and the position of the tag in the DAG in two large sub-networks of the English Wikipedia and a protein-protein interaction network. We also study the tag co-occurrence statistics by introducing a two-dimensional (2D) tag-distance distribution preserving both the difference in the levels and the absolute distance in the DAG for the co-occurring pairs of tags. Our most interesting finding is that the local relevance of tags in the DAG (i.e. their rank or significance as characterized by, e.g., the length of the branches starting from them) is much more important than their global distance from the root. Furthermore, we also introduce a simple tagging model based on random walks on the DAG, capable of

  6. Global Navigation Satellite Systems (GNSS: The Utmost Interdisciplinary Integrator

    Directory of Open Access Journals (Sweden)

    Bernd Eissfeller

    2015-08-01

    Full Text Available Currently four global satellite navigation systems are under modernization and development: The US American GPS III, the Russian GLONASS, the European Galileo and Chinese BeiDou systems. In the paper the interdisciplinary contributions of different scientific areas to GNSS are assessed. It is outlined that GNSS is not only a technical system but also a basic element of mobile computing high-tech market. At the same time a GNSS has the role of a force enabler in security related applications. Technology, market and security policies are interdependent and are sometimes in a relationship of tension. The goal of the paper is to describe the overall systemics of GNSS from a holistic point of view. The paper also addresses the human factor side of GNSS. The requirements on human resources in GNSS are at least two-fold: On the one hand very specialized engineers are needed; on the other hand the generalists are necessary who are able to understand the system aspects. Decision makers in institutions and industry need special knowledge in technologies, economics and political strategies. Is the current university system able to educate and prepare such generalists? Are specialized master courses for GNSS needed? Are external training courses necessary?

  7. What Is an Ear Infection?

    Science.gov (United States)

    ... your ear with a special flashlight called an otoscope (say: OH-te-skope). With the otoscope, the doctor can see your eardrum , the thin ... and middle ear. The doctor may use the otoscope to blow a little puff of air in ...

  8. Precise GNSS Positioning Using Smart Devices

    Directory of Open Access Journals (Sweden)

    Eugenio Realini

    2017-10-01

    Full Text Available The recent access to GNSS (Global Navigation Satellite System phase observations on smart devices, enabled by Google through its Android operating system, opens the possibility to apply precise positioning techniques using off-the-shelf, mass-market devices. The target of this work is to evaluate whether this is feasible, and which positioning accuracy can be achieved by relative positioning of the smart device with respect to a base station. Positioning of a Google/HTC Nexus 9 tablet was performed by means of batch least-squares adjustment of L1 phase double-differenced observations, using the open source goGPS software, over baselines ranging from approximately 10 m to 8 km, with respect to both physical (geodetic or low-cost and virtual base stations. The same positioning procedure was applied also to a co-located u-blox low-cost receiver, to compare the performance between the receiver and antenna embedded in the Nexus 9 and a standard low-cost single-frequency receiver with external patch antenna. The results demonstrate that with a smart device providing raw GNSS phase observations, like the Nexus 9, it is possible to reach decimeter-level accuracy through rapid-static surveys, without phase ambiguity resolution. It is expected that sub-centimeter accuracy could be achieved, as demonstrated for the u-blox case, if integer phase ambiguities were correctly resolved.

  9. Precise GNSS Positioning Using Smart Devices.

    Science.gov (United States)

    Realini, Eugenio; Caldera, Stefano; Pertusini, Lisa; Sampietro, Daniele

    2017-10-24

    The recent access to GNSS (Global Navigation Satellite System) phase observations on smart devices, enabled by Google through its Android operating system, opens the possibility to apply precise positioning techniques using off-the-shelf, mass-market devices. The target of this work is to evaluate whether this is feasible, and which positioning accuracy can be achieved by relative positioning of the smart device with respect to a base station. Positioning of a Google/HTC Nexus 9 tablet was performed by means of batch least-squares adjustment of L1 phase double-differenced observations, using the open source goGPS software, over baselines ranging from approximately 10 m to 8 km, with respect to both physical (geodetic or low-cost) and virtual base stations. The same positioning procedure was applied also to a co-located u-blox low-cost receiver, to compare the performance between the receiver and antenna embedded in the Nexus 9 and a standard low-cost single-frequency receiver with external patch antenna. The results demonstrate that with a smart device providing raw GNSS phase observations, like the Nexus 9, it is possible to reach decimeter-level accuracy through rapid-static surveys, without phase ambiguity resolution. It is expected that sub-centimeter accuracy could be achieved, as demonstrated for the u-blox case, if integer phase ambiguities were correctly resolved.

  10. Ultra-Tightly Coupled GNSS/INS for small UAVs

    DEFF Research Database (Denmark)

    Olesen, Daniel; Jakobsen, Jakob; Knudsen, Per

    2017-01-01

    fitted onto a small UAV. The storage of IF samples together with measurements from an Inertial Measurement Unit ( IMU) has allowed the authors to process an Ultra-Tightly Coupled ( U.T.C.) GNSS/INS solution from real data collected with a small UAV. The focus of this paper has been to investigate......This paper describes an ultra-tight integration of a Global Navigation Satellite System ( GNSS) receiver and an Inertial Navigation System ( INS) for small Unmanned Aerial Vehicles ( UAVs). The system is based on a low-cost and low-weight GNSS Intermediate Frequency ( IF) sampler which has been...

  11. The Performance of a Tight Ins/gnss/photogrammetric Integration Scheme for Land Based MMS Applications in Gnss Denied Environments

    Science.gov (United States)

    Chu, C. H.; Chiang, K. W.

    2012-07-01

    Nowadays the most common technologies used for positioning and orientation of a mobile mapping system include using Global Navigation Satellite System (GNSS) as a major positioning sensor and Inertial Navigation System (INS) as the major orientation sensor. The integration strategy of the most commercially system is the loosely coupled (LC) architecture, that has the simplest architecture using the GNSS solutions to aid the INS navigation information with proper optimization estimator. The LC does combine the two sensors' solutions when the number of tracked satellite is more than four. In recent year, another commonly integration strategy is known as tightly coupled (TC) architecture. Because the TC uses the GNSS measurements to aid INS, it can integrate measurements provided by GNSS receiver and INS unless no GNSS satellite is tracked. Obviously, the TC architecture is a better candidate for land based mobile mapping applications than LC in Taiwan. Unfortunately, there are still many GNSS denied environment in the urban area, therefore the TC architecture is still not robust and stable enough for MMS application. The overall objective of this paper is to provide a scheme that tightly integrates INS/GNSS and Photogrammetric for land based MMS applications with sufficient and stable POS solutions during GNSS outages. In the traditional photogrammetry operation, numerous ground control points are applied to compute those Exterior Orientation Parameters (EOPs) of cameras by bundle adjustment. The key opinion is to derive the INS centre position and attitude and reconstruct 3-D tracking and 3-D object space by cameras EOPs. The proposed algorithm is verified using field test data collected in GNSS denied environments and the preliminary results presented in this study illustrated that the proposed algorithm is able to provide 60% improvement in terms of positioning and orientation accuracy in Taipei and Tainan cities.

  12. THE PERFORMANCE OF A TIGHT INS/GNSS/PHOTOGRAMMETRIC INTEGRATION SCHEME FOR LAND BASED MMS APPLICATIONS IN GNSS DENIED ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    C. H. Chu

    2012-07-01

    Full Text Available Nowadays the most common technologies used for positioning and orientation of a mobile mapping system include using Global Navigation Satellite System (GNSS as a major positioning sensor and Inertial Navigation System (INS as the major orientation sensor. The integration strategy of the most commercially system is the loosely coupled (LC architecture, that has the simplest architecture using the GNSS solutions to aid the INS navigation information with proper optimization estimator. The LC does combine the two sensors’ solutions when the number of tracked satellite is more than four. In recent year, another commonly integration strategy is known as tightly coupled (TC architecture. Because the TC uses the GNSS measurements to aid INS, it can integrate measurements provided by GNSS receiver and INS unless no GNSS satellite is tracked. Obviously, the TC architecture is a better candidate for land based mobile mapping applications than LC in Taiwan. Unfortunately, there are still many GNSS denied environment in the urban area, therefore the TC architecture is still not robust and stable enough for MMS application. The overall objective of this paper is to provide a scheme that tightly integrates INS/GNSS and Photogrammetric for land based MMS applications with sufficient and stable POS solutions during GNSS outages. In the traditional photogrammetry operation, numerous ground control points are applied to compute those Exterior Orientation Parameters (EOPs of cameras by bundle adjustment. The key opinion is to derive the INS centre position and attitude and reconstruct 3-D tracking and 3-D object space by cameras EOPs. The proposed algorithm is verified using field test data collected in GNSS denied environments and the preliminary results presented in this study illustrated that the proposed algorithm is able to provide 60% improvement in terms of positioning and orientation accuracy in Taipei and Tainan cities.

  13. AMIGHO: Automated Metadata Ingest for GNSS Hydrology within OODT

    Data.gov (United States)

    National Aeronautics and Space Administration — GNSS sites installed by surveyors and geophysicists to measure land motions can also provide valuable and cost-efficient information about three critical hydrologic...

  14. MULTI-GNSS RECEIVER FOR AEROSPACE NAVIGATION AND POSITIONING APPLICATIONS

    Directory of Open Access Journals (Sweden)

    T. R. Peres

    2014-03-01

    Full Text Available The upcoming Galileo system opens a wide range of new opportunities in the Global Navigation Satellite System (GNSS market. However, the characteristics of the future GNSS signals require the development of new GNSS receivers. In the frame of the REAGE project, DEIMOS and ISEL have developed a GNSS receiver targeted for aerospace applications, supporting current and future GPS L1 and Galileo E1 signals, based on commercial (or, in the furthest extent, industrial grade components. Although the REAGE project aimed at space applications, the REAGE receiver is also applicable to many terrestrial applications (ground or airborne, such as Georeferencing and Unmanned Aerial Vehicle (UAV navigation. This paper presents the architecture and features of the REAGE receiver, as well as some results of the validation campaign with GPS L1 and Galileo E1 signals.

  15. GNSS global navigation satellite systems : GPS, GLONASS, Galileo, and more

    CERN Document Server

    Hofmann-Wellenhof, Bernhard; Wasle, Elmar

    2008-01-01

    This book is an extension to the acclaimed scientific bestseller "GPS - Theory and Practice". It covers Global Navigation Satellite Systems (GNSS) and includes the Russian GLONASS, the European system Galileo, and additional systems.

  16. Angle-of-Arrival Assisted GNSS Collaborative Positioning.

    Science.gov (United States)

    Huang, Bin; Yao, Zheng; Cui, Xiaowei; Lu, Mingquan

    2016-06-20

    For outdoor and global navigation satellite system (GNSS) challenged scenarios, collaborative positioning algorithms are proposed to fuse information from GNSS satellites and terrestrial wireless systems. This paper derives the Cramer-Rao lower bound (CRLB) and algorithms for the angle-of-arrival (AOA)-assisted GNSS collaborative positioning. Based on the CRLB model and collaborative positioning algorithms, theoretical analysis are performed to specify the effects of various factors on the accuracy of collaborative positioning, including the number of users, their distribution and AOA measurements accuracy. Besides, the influences of the relative location of the collaborative users are also discussed in order to choose appropriate neighboring users, which is in favor of reducing computational complexity. Simulations and actual experiment are carried out with several GNSS receivers in different scenarios, and the results are consistent with theoretical analysis.

  17. GNSS Receiver Identification Using Clock-Derived Metrics.

    Science.gov (United States)

    Borio, Daniele; Gioia, Ciro; Cano Pons, Eduardo; Baldini, Gianmarco

    2017-09-15

    Falsifying Global Navigation Satellite System (GNSS) data with a simulator or with a fake receiver can have a significant economic or safety impact in many transportation applications where Position, Velocity and Time (PVT) are used to enforce a regulation. In this context, the authentication of the source of the PVT data (i.e., the GNSS receiver) is a requirement since data faking can become a serious threat. Receiver fingerprinting techniques represent possible countermeasures to verify the authenticity of a GNSS receiver and of its data. Herein, the potential of clock-derived metrics for GNSS receiver fingerprinting is investigated, and a filter approach is implemented for feature selection. Novel experimental results show that three intrinsic features are sufficient to identify a receiver. Moreover, the adopted technique is time effective as data blocks of about 40 min are sufficient to produce stable features for fingerprinting.

  18. TOGA - A GNSS Reflections Instrument for Remote Sensing Using Beamforming

    Science.gov (United States)

    Esterhuizen, S.; Meehan, T. K.; Robison, D.

    2009-01-01

    Remotely sensing the Earth's surface using GNSS signals as bi-static radar sources is one of the most challenging applications for radiometric instrument design. As part of NASA's Instrument Incubator Program, our group at JPL has built a prototype instrument, TOGA (Time-shifted, Orthometric, GNSS Array), to address a variety of GNSS science needs. Observing GNSS reflections is major focus of the design/development effort. The TOGA design features a steerable beam antenna array which can form a high-gain antenna pattern in multiple directions simultaneously. Multiple FPGAs provide flexible digital signal processing logic to process both GPS and Galileo reflections. A Linux OS based science processor serves as experiment scheduler and data post-processor. This paper outlines the TOGA design approach as well as preliminary results of reflection data collected from test flights over the Pacific ocean. This reflections data demonstrates observation of the GPS L1/L2C/L5 signals.

  19. Human ear recognition by computer

    CERN Document Server

    Bhanu, Bir; Chen, Hui

    2010-01-01

    Biometrics deals with recognition of individuals based on their physiological or behavioral characteristics. The human ear is a new feature in biometrics that has several merits over the more common face, fingerprint and iris biometrics. Unlike the fingerprint and iris, it can be easily captured from a distance without a fully cooperative subject, although sometimes it may be hidden with hair, scarf and jewellery. Also, unlike a face, the ear is a relatively stable structure that does not change much with the age and facial expressions. ""Human Ear Recognition by Computer"" is the first book o

  20. Tag-elese or The Language of Tags

    Directory of Open Access Journals (Sweden)

    Jan Simons

    2008-01-01

    Full Text Available The core "meme" of Web 2.0 from which almost all other memes radiated was: 'You control your own data' (O'Reilly, 2005, 3. Key instruments for this user control are tagging systems that allow users to freely assign keywords of their own choosing to Internet resources of their own making as well as to documents produced by others. Of course, freely chosen keywords tags do not necessarily follow prefixed taxonomies or classification systems. But going by the maxim that interaction creates similarity and similarity creates interaction, the idea - or hope - is, however, that the tagging practices of individual users will eventually converge into an emergent common vocabulary or folksonomy (Merholz, 2004; Shirky, 2005; Vander Wal, 2005b; Mika, 2007. It is far from clear, however, that free tagging systems will eventually yield controlled vocabularies, and there are many incentives for idiosyncratic, ambiguous, and inconsistent uses of tags. Left to themselves, free tagging systems seem to be too wild and too chaotic for any order to emerge. But are these free tagging systems really as "feral" as they seem to be, or do they only look uncontrolled because one has been looking for order in the wrong place? I have done a quick-and-dirty" analysis of Flickr's tag cloud. The concept was: if folksonomies encourage users to tap on their own vernacular, everyday natural language must somehow "guide" the tagging practices of users of tagging systems. Flickr's tag cloud has been choosen because it may teach us something about tagging systems and folksonomies, and not - or not primarily - because of what tags may tell us about pictures.

  1. Receptor GNSS multiantena para aplicaciones aeroespaciales

    OpenAIRE

    Cogo, Jorge; López La Valle, Ramón G.; Puga, Gerardo L.; Smidt, Javier A.; Díaz, Juan G.; García, Javier Gonzalo; Roncagliolo, Pedro Agustín; Muravchik, Carlos Horacio

    2013-01-01

    La determinación de la posición y velocidad del vehículo es una de las tareas críticas en las aplicaciones aeroespaciales como es el caso de aviones, satélites o cohetes. En los últimos años esta tarea se ha visto favorecida por el despliegue de los Sistemas de Navegación Global por Satélite (GNSS). Estos sistemas, utilizando como base una constelación de satélites que envían señales a la superficie terrestre, permiten que un usuario que cuente con un receptor adecuado pueda obtener esta info...

  2. Selected considerations of implementation of the GNSS

    Science.gov (United States)

    Cwiklak, Janusz; Fellner, Andrzej; Fellner, Radoslaw; Jafernik, Henryk; Sledzinski, Janusz

    2014-05-01

    The article describes analysis of the safety and risk for the implementation of precise approach procedures (Localizer Performance and Vertical Guidance - LPV) with GNSS sensor at airports in Warsaw and Katowice. There were used some techniques of the identification of threats (inducing controlled flight into terrain, landing accident, mid-air collision) and evaluations methods based on Fault Tree Analysis, probability of the risk, safety risk evaluation matrix and Functional Hazard Assesment. Also safety goals were determined. Research led to determine probabilities of appearing of threats, as well as allow compare them with regard to the ILS. As a result of conducting the Preliminary System Safety Assessment (PSSA), there were defined requirements essential to reach the required level of the safety. It is worth to underline, that quantitative requirements were defined using FTA.

  3. Estimating and Comparing Dam Deformation Using Classical and GNSS Techniques.

    Science.gov (United States)

    Barzaghi, Riccardo; Cazzaniga, Noemi Emanuela; De Gaetani, Carlo Iapige; Pinto, Livio; Tornatore, Vincenza

    2018-03-02

    Global Navigation Satellite Systems (GNSS) receivers are nowadays commonly used in monitoring applications, e.g., in estimating crustal and infrastructure displacements. This is basically due to the recent improvements in GNSS instruments and methodologies that allow high-precision positioning, 24 h availability and semiautomatic data processing. In this paper, GNSS-estimated displacements on a dam structure have been analyzed and compared with pendulum data. This study has been carried out for the Eleonora D'Arborea (Cantoniera) dam, which is in Sardinia. Time series of pendulum and GNSS over a time span of 2.5 years have been aligned so as to be comparable. Analytical models fitting these time series have been estimated and compared. Those models were able to properly fit pendulum data and GNSS data, with standard deviation of residuals smaller than one millimeter. These encouraging results led to the conclusion that GNSS technique can be profitably applied to dam monitoring allowing a denser description, both in space and time, of the dam displacements than the one based on pendulum observations.

  4. GNSS Clock Error Impacts on Radio Occultation Retrievals

    Science.gov (United States)

    Weiss, Jan; Sokolovskiy, Sergey; Schreiner, Bill; Yoon, Yoke

    2017-04-01

    We assess the impacts of GPS and GLONASS clock errors on radio occultation retrieval of bending angle, refractivity, and temperature from low Earth orbit. The major contributing factor is the interpretation of GNSS clock offsets sampled at 30 sec or longer intervals. Using 1 Hz GNSS clock estimates as truth we apply several interpolation and fitting schemes to evaluate how they affect the accuracy of atmospheric retrieval products. The results are organized by GPS and GLONASS space vehicle and the GNSS clock interpolation/fitting scheme. We find that bending angle error is roughly similar for all current GPS transmitters (about 0.7 mcrad) but note some differences related to the type of atomic oscillator onboard the transmitter satellite. GLONASS bending angle errors show more variation over the constellation and are approximately two times larger than GPS. An investigation of the transmitter clock spectra reveals this is due to more power in periods between 2-10 sec. Retrieved refractivity and temperature products show clear differences between GNSS satellite generations, and indicate that GNSS clocks sampled at intervals smaller than 5 sec significantly improve accuracy, particularly for GLONASS. We conclude by summarizing the tested GNSS clock estimation and application strategies in the context of current and future radio occultation missions.

  5. Global Ear. Werke 2001 - 2006

    Index Scriptorium Estoniae

    2006-01-01

    Dresdenis muusikafestivalil "Global Ear" 23.3.03 esitusel Eesti heliloojate muusika: Helena Tulve "lumineux/opaque", Jaan Rääts "Meditation", Mirjam Tally "Aura", Mati Kuulberg "Sonate Nr.4", Mari Vihmand "Seitsmele"

  6. Social Tagging of Mission Data

    Science.gov (United States)

    Norris, Jeffrey S.; Wallick, Michael N.; Joswig, Joseph C.; Powell, Mark W.; Torres, Recaredo J.; Mittman, David S.; Abramyan, Lucy; Crockett, Thomas M.; Shams, Khawaja S.; Fox, Jason M.; hide

    2010-01-01

    Mars missions will generate a large amount of data in various forms, such as daily plans, images, and scientific information. Often, there is a semantic linkage between images that cannot be captured automatically. Software is needed that will provide a method for creating arbitrary tags for this mission data so that items with a similar tag can be related to each other. The tags should be visible and searchable for all users. A new routine was written to offer a new and more flexible search option over previous applications. This software allows users of the MSLICE program to apply any number of arbitrary tags to a piece of mission data through a MSLICE search interface. The application of tags creates relationships between data that did not previously exist. These tags can be easily removed and changed, and contain enough flexibility to be specifically configured for any mission. This gives users the ability to quickly recall or draw attention to particular pieces of mission data, for example: Give a semantic and meaningful description to mission data; for example, tag all images with a rock in them with the tag "rock." Rapidly recall specific and useful pieces of data; for example, tag a plan as"driving template." Call specific data to a user s attention; for example, tag a plan as "for:User." This software is part of the MSLICE release, which was written in Java. It will run on any current Windows, Macintosh, or Linux system.

  7. Measuring sea surface height with a GNSS-Wave Glider

    Science.gov (United States)

    Morales Maqueda, Miguel Angel; Penna, Nigel T.; Foden, Peter R.; Martin, Ian; Cipollini, Paolo; Williams, Simon D.; Pugh, Jeff P.

    2017-04-01

    A GNSS-Wave Glider is a novel technique to measure sea surface height autonomously using the Global Navigation Satellite System (GNSS). It consists of an unmanned surface vehicle manufactured by Liquid Robotics, a Wave Glider, and a geodetic-grade GNSS antenna-receiver system, with the antenna installed on a mast on the vehicle's deck. The Wave Glider uses the differential wave motion through the water column for propulsion, thus guaranteeing an, in principle, indefinite autonomy. Solar energy is collected to power all on-board instrumentation, including the GNSS system. The GNSS-Wave Glider was first tested in Loch Ness in 2013, demonstrating that the technology is capable of mapping geoid heights within the loch with an accuracy of a few centimetres. The trial in Loch Ness did not conclusively confirm the reliability of the technique because, during the tests, the state of the water surface was much more benign than would normally be expect in the open ocean. We now report on a first deployment of a GNSS-Wave Glider in the North Sea. The deployment took place in August 2016 and lasted thirteen days, during which the vehicle covered a distance of about 350 nautical miles in the north western North Sea off Great Britain. During the experiment, the GNSS-Wave Glider experienced sea states between 1 (0-0.1 m wave heights) and 5 (2.5-4 m wave heights). The GNSS-Wave Glider data, recorded at 5 Hz frequency, were analysed using a post-processed kinematic GPS-GLONASS precise point positioning (PPP) approach, which were quality controlled using double difference GPS kinematic processing with respect to onshore reference stations. Filtered with a 900 s moving-average window, the PPP heights reveal geoid patterns in the survey area that are very similar to the EGM2008 geoid model, thus demonstrating the potential use of a GNSS-Wave Glider for marine geoid determination. The residual of subtracting the modelled or measured marine geoid from the PPP signal combines information

  8. Review on SAW RFID tags.

    Science.gov (United States)

    Plessky, Victor P; Reindl, Leonhard M

    2010-03-01

    SAW tags were invented more than 30 years ago, but only today are the conditions united for mass application of this technology. The devices in the 2.4-GHz ISM band can be routinely produced with optical lithography, high-resolution radar systems can be built up using highly sophisticated, but low-cost RF-chips, and the Internet is available for global access to the tag databases. The "Internet of Things," or I-o-T, will demand trillions of cheap tags and sensors. The SAW tags can overcome semiconductor-based analogs in many aspects: they can be read at a distance of a few meters with readers radiating power levels 2 to 3 orders lower, they are cheap, and they can operate in robust environments. Passive SAW tags are easily combined with sensors. Even the "anti-collision" problem (i.e., the simultaneous reading of many nearby tags) has adequate solutions for many practical applications. In this paper, we discuss the state-of-the-art in the development of SAW tags. The design approaches will be reviewed and optimal tag designs, as well as encoding methods, will be demonstrated. We discuss ways to reduce the size and cost of these devices. A few practical examples of tags using a time-position coding with 10(6) different codes will be demonstrated. Phase-coded devices can additionally increase the number of codes at the expense of a reduction of reading distance. We also discuss new and exciting perspectives of using ultra wide band (UWB) technology for SAW-tag systems. The wide frequency band available for this standard provides a great opportunity for SAW tags to be radically reduced in size to about 1 x 1 mm(2) while keeping a practically infinite number of possible different codes. Finally, the reader technology will be discussed, as well as detailed comparison made between SAW tags and IC-based semiconductor device.

  9. An Investigation into the Relationship between Ionospheric Scintillation and Loss of Lock in GNSS Receivers

    National Research Council Canada - National Science Library

    Meggs, Robert W; Mitchell, Cathryn N; Smith, Andrew M

    2006-01-01

    .... Scintillation can have an adverse effect on Global Navigation Satellite Systems (GNSS) signals as they pass from a satellite to a receiver, and extreme cases can cause a GNSS receiver to lose lock on the signal...

  10. Buddy Tag CONOPS and Requirements.

    Energy Technology Data Exchange (ETDEWEB)

    Brotz, Jay Kristoffer [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Deland, Sharon M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-12-01

    This document defines the concept of operations (CONOPS) and the requirements for the Buddy Tag, which is conceived and designed in collaboration between Sandia National Laboratories and Princeton University under the Department of State Key VerificationAssets Fund. The CONOPS describe how the tags are used to support verification of treaty limitations and is only defined to the extent necessary to support a tag design. The requirements define the necessary functions and desired non-functional features of the Buddy Tag at a high level

  11. Flavour tagging performance in LHCb

    International Nuclear Information System (INIS)

    Grabalosa Gandara, Marc

    2009-01-01

    To do precise CP violation measurements, the best possible determination of the flavour of the B-meson is necessary. This report summarizes the flavour tagging performances for the LHCb experiment. The flavour tagging is obtained through a combination of several methods, based on different signatures. The use of control channels, which are decays to flavour-specific final states, will allow to determine the wrong tag fraction ω (the probability of a tag to be wrong), which can be used as an input for the determination of CKM unitarity triangle angles.

  12. EPOS-GNSS - Improving the infrastructure for GNSS data and products in Europe

    Science.gov (United States)

    Fernandes, Rui; Bos, Machiel; Bruyninx, Carine; Crocker, Paul; Dousa, Jan; Socquet, Anne; Walpersdorf, Andrea; Avallone, Antonio; Ganas, Athanassios; Gunnar, Benedikt; Ionescu, Constantin; Kenyeres, Ambrus; Ozener, Haluk; Vergnolle, Mathilde; Lidberg, Martin; Liwosz, Tomek; Soehne, Wolfgang

    2017-04-01

    EPOS-IP WP10 - "GNSS Data & Products" is the Working Package 10 of the European Plate Observing System - Implementation Phase project in charge of implementing services for the geo-sciences community to access existing Pan-European Geodetic Infrastructures. WP10 is currently formed by representatives of participating European institutions but in the operational phase contributions will be solicited from the entire geodetic community. In fact, WP10 also includes members from other institutions/countries that formally are not participating in the EPOS-IP but will be key players in the future services to be provided by EPOS. Additionally, several partners are also key partners at EUREF, which is also actively collaborating with EPOS. The geodetic component of EPOS is dealing essentially with implementing an e-infrastructure to store and disseminate the continuous GNSS data from existing Research Infrastructures. Present efforts are on developing geodetic tools to support Solid Earth research by optimizing the existing resources. However, other research and technical applications (e.g., reference frames, meteorology, space weather) can also benefit in the future from the optimization of the geodetic resources in Europe. We present and discuss the status of the implementation of the thematic and core services (TCS) for GNSS data within EPOS and the related business plan. We explain the tools and web-services being developed towards the implementation of the best solutions that will permit to the end-users, and in particular geo-scientists, to access the geodetic data, derived solutions, and associated metadata using a transparent and standardized processes. We also detail the different DDSS (Data, Data-Products, Services, Software) that will be made available for the Operational Phase of EPOS, which will start to be tested and made available during 2017 and 2018.

  13. Technical note: Evaluation of an ear-attached movement sensor to record cow feeding behavior and activity

    NARCIS (Netherlands)

    Bikker, J.P.; Laar, van H.; Rump, P.; Doorenbos, J.; Meurs, van K.; Griffioen, G.M.; Dijkstra, J.

    2014-01-01

    The ability to monitor dairy cow feeding behavior and activity could improve dairy herd management. A 3-dimensional accelerometer (SensOor; Agis Automatisering BV, Harmelen, the Netherlands) has been developed that can be attached to ear identification tags. Based on the principle that behavior can

  14. Power Electronics Design of a Solar Powered In-car Wireless Tag for Asset Tracking and Parking Applications

    International Nuclear Information System (INIS)

    Zhu, D; Beeby, S P; Henaut, J

    2014-01-01

    This paper reports the design and testing of a power conditioning circuit for a solar powered in-car wireless tag for asset tracking and parking application. Existing long range asset tracking is based on the GSM/GPRS network, which requires expensive subscriptions. The EU FP7 project CEWITT aims at developing a credit card sized autonomous wireless tag with GNSS geo-positioning capabilities to ensure the integrity and cost effectiveness for parking applications. It was found in previous research that solar cells are the most suitable energy sources for this application. This study focused on the power electronics design for the wireless tag. A suitable solar cell was chosen for its high power density. Charging circuit, hysteresis control circuit and LDO were designed and integrated to meet the system requirement. Test results showed that charging efficiency of 80 % had been achieved

  15. Power Electronics Design of a Solar Powered In-car Wireless Tag for Asset Tracking and Parking Applications

    Science.gov (United States)

    Zhu, D.; Henaut, J.; Beeby, S. P.

    2014-11-01

    This paper reports the design and testing of a power conditioning circuit for a solar powered in-car wireless tag for asset tracking and parking application. Existing long range asset tracking is based on the GSM/GPRS network, which requires expensive subscriptions. The EU FP7 project CEWITT aims at developing a credit card sized autonomous wireless tag with GNSS geo-positioning capabilities to ensure the integrity and cost effectiveness for parking applications. It was found in previous research that solar cells are the most suitable energy sources for this application. This study focused on the power electronics design for the wireless tag. A suitable solar cell was chosen for its high power density. Charging circuit, hysteresis control circuit and LDO were designed and integrated to meet the system requirement. Test results showed that charging efficiency of 80 % had been achieved.

  16. 3D finite element model of the chinchilla ear for characterizing middle ear functions

    OpenAIRE

    Wang, Xuelin; Gan, Rong Z.

    2016-01-01

    Chinchilla is a commonly used animal model for research of sound transmission through the ear. Experimental measurements of the middle ear transfer function in chinchillas have shown that the middle ear cavity greatly affects the tympanic membrane (TM) and stapes footplate (FP) displacements. However, there is no finite element (FE) model of the chinchilla ear available in the literature to characterize the middle ear functions with the anatomical features of the chinchilla ear. This paper re...

  17. 3D printed bionic ears.

    Science.gov (United States)

    Mannoor, Manu S; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A; Soboyejo, Winston O; Verma, Naveen; Gracias, David H; McAlpine, Michael C

    2013-06-12

    The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing.

  18. Ear Disorders in Scuba Divers

    Directory of Open Access Journals (Sweden)

    MH Azizi

    2010-12-01

    Full Text Available History of underwater diving dates back to antiquity. Breath-hold technique in diving was known to the ancient nations. However, deep diving progressed only in the early decades of the 19th century as the result of advancements in efficient underwater technologies which subsequently led to invention of sophisticated sets of scuba diving in the 20th century. Currently, diving is performed for various purposes including commercial, recreational, military, underwater construction, oil industry, underwater archeology and scientific assessment of marine life. By increasing popularity of underwater diving, dive-related medical conditions gradually became more evident and created a new challenge for the health care professionals, so that eventually, a specialty the so-called “diving medicine” was established. Most of the diving-associated disorders appear in the head and neck. The most common of all occupational disorders associated with diving are otologic diseases. External otitis has been reported as the most common otolaryngologic problem in underwater divers. Exostosis of the external ear canal may be formed in divers as the result of prolonged diving in cold waters. Other disorders of the ear and paranasal sinuses in underwater divers are caused by barometric pressure change (i.e., barotraumas, and to a lesser extent by decompression sickness. Barotrauma of the middle ear is the most prevalent barotrauma in divers. The inner ear barotraumas, though important, is less common. The present paper is a brief overview of diving-related ear disorders particularly in scuba divers.

  19. Undifferenced and single differenced GNSS noise analysis through a constrained baseline vector

    NARCIS (Netherlands)

    Buist, P.J.; Imparato, D.

    2014-01-01

    GNSS noise characteristics can be obtained by short and zero baseline analysis, for both pseudorange and carrier phase measurements. Differencing observations from a GNSS satellite tracked by two GNSS receivers (connected to the same or different antennas) will explicitly eliminate common errors. In

  20. The affine constrained GNSS attitude model and its multivariate integer least-squares solution

    NARCIS (Netherlands)

    Teunissen, P.J.G.

    2012-01-01

    A new global navigation satellite system (GNSS) carrier-phase attitude model and its solution are introduced in this contribution. This affine-constrained GNSS attitude model has the advantage that it avoids the computational complexity of the orthonormality-constrained GNSS attitude model, while it

  1. Altimetry with GNSS-R interferometry : First proof of concept experiment

    NARCIS (Netherlands)

    Rius, A.; Nogués-Correig, O.; Ribó, S.; Cardellach, E.; Oliveras, S.; Valencia, E.; Park, H.; Tarongi, J.M.; Camps, A.; Van der Marel, H.; Van Bree, R.; Altena, B.; Martín-Neira, M.

    2011-01-01

    The Global Navigation Satellite System Reflectometry (GNSS-R) concept was conceived as a means to densify radar altimeter measurements of the sea surface. Until now, the GNSS-R concept relied on open access to GNSS transmitted codes. Recently, it has been proposed that the ranging capability of the

  2. Snapshot Software Receiver for GNSS in Weak Signal Environments : An Innovative Approach for Galileo E5

    NARCIS (Netherlands)

    Carrasco-Martos, S.; López-Risueño, G.; Jiménez-Baños, D.; Gill, E.K.A.

    2010-01-01

    Global Navigation Satellite System (GNSS) positioning has turned out to be an enabler of Location-Based Services (LBS). This has motivated in recent years an increasing research activity on signal processing techniques for GNSS receivers. However, one main limitation faced by these GNSS receivers is

  3. LHCb Tag Collector

    CERN Document Server

    Fuente Fernàndez, P; Cousin, N

    2011-01-01

    The LHCb physics software consists of hundreds of packages, each of which is developed by one or more physicists. When the developers have some code changes that they would like released, they commit them to the version control system, and enter the revision number into a database. These changes have to be integrated into a new release of each of the physics analysis applications. Tests are then performed by a nightly build system, which rebuilds various configurations of the whole software stack and executes a suite of run-time functionality tests. A Tag Collector system has been developed using solid standard technologies to cover both the use cases of developers and integration managers. A simple Web interface, based on an AJAX-like technology, is available. Integration with software management and Nightly Build programs is possible via a Python API. Data are stored in a relational database with the help of an ORM (Object-Relational Mapping) library.

  4. Application of GNSS Methods for Monitoring Offshore Platform Deformation

    Science.gov (United States)

    Myint, Khin Cho; Nasir Matori, Abd; Gohari, Adel

    2018-03-01

    Global Navigation Satellite System (GNSS) has become a powerful tool for high-precision deformation monitoring application. Monitoring of deformation and subsidence of offshore platform due to factors such as shallow gas phenomena. GNSS is the technical interoperability and compatibility between various satellite navigation systems such as modernized GPS, Galileo, reconstructed GLONASS to be used by civilian users. It has been known that excessive deformation affects platform structurally, causing loss of production and affects the efficiency of the machinery on board the platform. GNSS have been proven to be one of the most precise positioning methods where by users can get accuracy to the nearest centimeter of a given position from carrier phase measurement processing of GPS signals. This research is aimed at using GNSS technique, which is one of the most standard methods to monitor the deformation of offshore platforms. Therefore, station modeling, which accounts for the spatial correlated errors, and hence speeds up the ambiguity resolution process is employed. It was found that GNSS combines the high accuracy of the results monitoring the offshore platforms deformation with the possibility of survey.

  5. Spacecraft orbit propagator integration with GNSS in a simulated scenario

    Science.gov (United States)

    Jing, Shuai; Zhan, Xingqun; Zhu, Zhenghong

    2017-09-01

    When space vehicles operate above the Global Navigation Satellite System (GNSS) constellation or even above geosynchronous orbit, it is common that the traditional GNSS single-epoch solution can't meet the requirement of orbit determination (OD). To provide the required OD accuracy continuously, a new designed spacecraft orbit propagator (OP) is combined with the GNSS observations in a deep integration mode. Taking both the computational complexity and positioning accuracy into consideration, the orbit propagator is optimized based on a simplified fourth order Runge-Kutta integral aided with empirical acceleration model. A simulation scenario containing a typical Highly-inclined Elliptical Orbit (HEO) user and GPS constellation is established on a HwaCreat™ GNSS signal simulator to testify the performance of the design. The numerical test results show that the maximum propagation error of the optimized orbit propagator does not exceed 1000 m within a day, which is superior to conventional OPs. If the new OP is deeply integrated with GNSS in our proposed scheme, the 95% SEP for the OD accuracy is 10.0005 m, and the time to first fix (TTFF) values under cold and warm start conditions are reduced by at least 7 s and 2 s respectively, which proves its advantage over loose integration and tight integration.

  6. Planning of an Experiment for VLBI Tracking of GNSS Satellites

    Science.gov (United States)

    Tornatore, Vincenza; Hass, Ruediger; Molera, Guifre; Pogrebenko, Sergei

    2010-01-01

    As a preparation for future possible orbit determination of global navigation satellite system (GNSS) satellites by VLBI observations an initial three-station experiment was planned and performed in January 2009. The goal was to get first experience and to verify the feasibility of using the method for accurate satellite tracking. GNSS orbits related to a satellite constellation can be expressed in the Terrestrial Reference Frame. A comparison with orbit results that might be obtained by VLBI can give valuable information on how the GNSS reference frame and the VLBI reference frame are linked. We present GNSS transmitter specifications and experimental results of the observations of some GLONASS satellites together with evaluations for the expected signal strengths at telescopes. The satellite flux densities detected on the Earth s surface are very high. The narrow bandwidth of the GNSS signal partly compensates for potential problems at the receiving stations, and signal attenuation is necessary. Attempts to correlate recorded data have been performed with different software.

  7. The Rise of GNSS Reflectometry for Earth Remote Sensing

    Science.gov (United States)

    Zuffada, Cinzia; Li, Zhijin; Nghiem, Son V.; Lowe, Steve; Shah, Rashmi; Clarizia, Maria Paola; Cardellach, Estel

    2015-01-01

    The Global Navigation Satellite System (GNSS) reflectometry, i.e. GNSS-R, is a novel remote-sensing technique first published in that uses GNSS signals reflected from the Earth's surface to infer its surface properties such as sea surface height (SSH), ocean winds, sea-ice coverage, vegetation, wetlands and soil moisture, to name a few. This communication discusses the scientific value of GNSS-R to (a) furthering our understanding of ocean mesoscale circulation toward scales finer than those that existing nadir altimeters can resolve, and (b) mapping vegetated wetlands, an emerging application that might open up new avenues to map and monitor the planet's wetlands for methane emission assessments. Such applications are expected to be demonstrated by the availability of data from GEROS-ISS, an ESA experiment currently in phase A, and CyGNSS [3], a NASA mission currently in development. In particular, the paper details the expected error characteristics and the role of filtering played in the assimilation of these data to reduce the altimetric error (when averaging many measurements).

  8. 3D finite element model of the chinchilla ear for characterizing middle ear functions.

    Science.gov (United States)

    Wang, Xuelin; Gan, Rong Z

    2016-10-01

    Chinchilla is a commonly used animal model for research of sound transmission through the ear. Experimental measurements of the middle ear transfer function in chinchillas have shown that the middle ear cavity greatly affects the tympanic membrane (TM) and stapes footplate (FP) displacements. However, there is no finite element (FE) model of the chinchilla ear available in the literature to characterize the middle ear functions with the anatomical features of the chinchilla ear. This paper reports a recently completed 3D FE model of the chinchilla ear based on X-ray micro-computed tomography images of a chinchilla bulla. The model consisted of the ear canal, TM, middle ear ossicles and suspensory ligaments, and the middle ear cavity. Two boundary conditions of the middle ear cavity wall were simulated in the model as the rigid structure and the partially flexible surface, and the acoustic-mechanical coupled analysis was conducted with these two conditions to characterize the middle ear function. The model results were compared with experimental measurements reported in the literature including the TM and FP displacements and the middle ear input admittance in chinchilla ear. An application of this model was presented to identify the acoustic role of the middle ear septa-a unique feature of chinchilla middle ear cavity. This study provides the first 3D FE model of the chinchilla ear for characterizing the middle ear functions through the acoustic-mechanical coupled FE analysis.

  9. [Paracoccidioidomycosis of the external ear].

    Science.gov (United States)

    Sambourg, E; Demar, M; Simon, S; Blanchet, D; Dufour, J; Sainte-Marie, D; Fior, A; Carme, B; Aznar, C; Couppié, P

    2014-01-01

    Paracoccidioidomycosis is a systemic fungal infection common in Latin America. Cutaneous involvement is frequent and usually affects multiple sites, being most frequently associated with lesions of the oropharyngeal mucosa. The cutaneous form on its own is rare. We report a case of paracoccidioidomycosis isolated from the ear of a 43-year-old immunocompetent man. The lesion consisted of a partially ulcerated plaque on the auricle of the left ear. Direct examination, histopathological examination and PCR revealed the presence in the skin lesion of yeasts identified as Paracoccidioides brasiliensis. The sites of paracoccidioidomycosis on the ear can be confused with other tropical diseases frequently found in the Amazon region such as leishmaniasis, leprosy and lobomycosis. The absence of any other cutaneous sites in this case raised the question of whether the lesion was of primary or secondary origin. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  10. Development of the inner ear.

    Science.gov (United States)

    Whitfield, Tanya T

    2015-06-01

    The vertebrate inner ear is a sensory organ of exquisite design and sensitivity. It responds to sound, gravity and movement, serving both auditory (hearing) and vestibular (balance) functions. Almost all cell types of the inner ear, including sensory hair cells, sensory neurons, secretory cells and supporting cells, derive from the otic placode, one of the several ectodermal thickenings that arise around the edge of the anterior neural plate in the early embryo. The developmental patterning mechanisms that underlie formation of the inner ear from the otic placode are varied and complex, involving the reiterative use of familiar signalling pathways, together with roles for transcription factors, transmembrane proteins, and extracellular matrix components. In this review, I have selected highlights that illustrate just a few of the many recent discoveries relating to the development of this fascinating organ system. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Semiotic dynamics and collaborative tagging.

    Science.gov (United States)

    Cattuto, Ciro; Loreto, Vittorio; Pietronero, Luciano

    2007-01-30

    Collaborative tagging has been quickly gaining ground because of its ability to recruit the activity of web users into effectively organizing and sharing vast amounts of information. Here we collect data from a popular system and investigate the statistical properties of tag cooccurrence. We introduce a stochastic model of user behavior embodying two main aspects of collaborative tagging: (i) a frequency-bias mechanism related to the idea that users are exposed to each other's tagging activity; (ii) a notion of memory, or aging of resources, in the form of a heavy-tailed access to the past state of the system. Remarkably, our simple modeling is able to account quantitatively for the observed experimental features with a surprisingly high accuracy. This points in the direction of a universal behavior of users who, despite the complexity of their own cognitive processes and the uncoordinated and selfish nature of their tagging activity, appear to follow simple activity patterns.

  12. Engineering the ATLAS TAG Browser

    CERN Document Server

    Zhang, Q; The ATLAS collaboration

    2011-01-01

    ELSSI is a web-based event metadata (TAG) browser and event-level selection service for ATLAS. TAGs from all ATLAS physics and Monte Carlo data sets are routinely loaded into Oracle databases as an integral part of event processing. As data volumes increase, more and more sites are joining the distributed TAG data hosting topology. Meanwhile, TAG content and database schemata continue to evolve as new user requirements and additional sources of metadata emerge. All of this has posed many challenges to the development of ELSSI, which must support vast amounts of TAG data while source, content, geographic locations, and user query patterns may change over time. In this paper, we describe some of the challenges encountered in the process of developing ELSSI, and the software engineering strategies adopted to address those challenges. Approaches to management of access to data, browsing, data rendering, query building, query validation, execution, connection management, and communication with auxiliary services a...

  13. Panoramic zonography in ear radiography

    International Nuclear Information System (INIS)

    Hallikainen, D.; Sjoeblom, C.J.; Toetterman, S.; Melartin, E.; Paukku, P.; Helsinki Univ. Central Hospital

    1983-01-01

    Thirty ears in 15 patients were examined by plain film radiography and by panoramic zonography with two tracks: A cylindrical concave image layer with 26 mm. radius and a paired sagittal image layer, at 51 mm. distance from midline. The films were interpreted according to the visibility of 23 different anatomic details. On panoramic films the visualization was better in 14 details, equal in 6 and worse in 3 compared to the plain films. The result suggests that panoramic techniques can replace conventional radiography of the ear. (orig.)

  14. Traffic Flow Detection Using GNSS-R Signals

    Directory of Open Access Journals (Sweden)

    YANG Lei

    2018-03-01

    Full Text Available In order to detect traffic conditions effectively, a new method of traffic flow detection using GNSS-R (Global Navigation Satellite System-Reflected signals is proposed. In this method, the direct signals and reflected signals of GNSS are received by two types of antennas respectively and collected by an universal receiver.After signal processing in a SDR(Software Defined Receiver, the correlated power of direct channel and reflected channel, and also the satellites' elevation angles can be obtained. Then vehicles can be detected by the method of dielectric constant retrieving.Test results show that vehicles in the area can be detected effectively using this method, and prove the feasibility of traffic flow detection using GNSS-R signals.

  15. GNSS Spoofing Detection Based on Signal Power Measurements: Statistical Analysis

    Directory of Open Access Journals (Sweden)

    V. Dehghanian

    2012-01-01

    Full Text Available A threat to GNSS receivers is posed by a spoofing transmitter that emulates authentic signals but with randomized code phase and Doppler values over a small range. Such spoofing signals can result in large navigational solution errors that are passed onto the unsuspecting user with potentially dire consequences. An effective spoofing detection technique is developed in this paper, based on signal power measurements and that can be readily applied to present consumer grade GNSS receivers with minimal firmware changes. An extensive statistical analysis is carried out based on formulating a multihypothesis detection problem. Expressions are developed to devise a set of thresholds required for signal detection and identification. The detection processing methods developed are further manipulated to exploit incidental antenna motion arising from user interaction with a GNSS handheld receiver to further enhance the detection performance of the proposed algorithm. The statistical analysis supports the effectiveness of the proposed spoofing detection technique under various multipath conditions.

  16. Research Progress and Prospect of GNSS Space Environment Science

    Directory of Open Access Journals (Sweden)

    YAO Yibin

    2017-10-01

    Full Text Available Troposphere and ionosphere are two important components of the near-earth space environment. They are close to the surface of the earth and have great influence on human life. The developments of Global Navigation Satellite System (GNSS over the past several decades provide a great opportunity for the GNSS-based space environment science. This review summarizes the research progress and prospect of the GNSS-based research of the Earth's troposphere and ionosphere. On the tropospheric perspective, modeling of the key tropospheric parameters and inversion of precipitable water vapor (PWV are dominant researching fields. On the ionospheric perspective, 2D/3D ionospheric models and regional/global ionospheric monitoring are dominant researching fields.

  17. Frequent Arousals from Winter Torpor in Rafinesque’s Big-Eared Bat (Corynorhinus rafinesquii)

    Science.gov (United States)

    Johnson, Joseph S.; Lacki, Michael J.; Thomas, Steven C.; Grider, John F.

    2012-01-01

    Extensive use of torpor is a common winter survival strategy among bats; however, data comparing various torpor behaviors among species are scarce. Winter torpor behaviors are likely to vary among species with different physiologies and species inhabiting different regional climates. Understanding these differences may be important in identifying differing susceptibilities of species to white-nose syndrome (WNS) in North America. We fitted 24 Rafinesque’s big-eared bats (Corynorhinus rafinesquii) with temperature-sensitive radio-transmitters, and monitored 128 PIT-tagged big-eared bats, during the winter months of 2010 to 2012. We tested the hypothesis that Rafinesque’s big-eared bats use torpor less often than values reported for other North American cave-hibernators. Additionally, we tested the hypothesis that Rafinesque’s big-eared bats arouse on winter nights more suitable for nocturnal foraging. Radio-tagged bats used short (2.4 d ± 0.3 (SE)), shallow (13.9°C ± 0.6) torpor bouts and switched roosts every 4.1 d ± 0.6. Probability of arousal from torpor increased linearly with ambient temperature at sunset (P<0.0001), and 83% (n = 86) of arousals occurred within 1 hr of sunset. Activity of PIT-tagged bats at an artificial maternity/hibernaculum roost between November and March was positively correlated with ambient temperature at sunset (P<0.0001), with males more active at the roost than females. These data show Rafinesque’s big-eared bat is a shallow hibernator and is relatively active during winter. We hypothesize that winter activity patterns provide Corynorhinus species with an ecological and physiological defense against the fungus causing WNS, and that these bats may be better suited to withstand fungal infection than other cave-hibernating bat species in eastern North America. PMID:23185427

  18. Frequent arousals from winter torpor in Rafinesque's big-eared bat (Corynorhinus rafinesquii.

    Directory of Open Access Journals (Sweden)

    Joseph S Johnson

    Full Text Available Extensive use of torpor is a common winter survival strategy among bats; however, data comparing various torpor behaviors among species are scarce. Winter torpor behaviors are likely to vary among species with different physiologies and species inhabiting different regional climates. Understanding these differences may be important in identifying differing susceptibilities of species to white-nose syndrome (WNS in North America. We fitted 24 Rafinesque's big-eared bats (Corynorhinus rafinesquii with temperature-sensitive radio-transmitters, and monitored 128 PIT-tagged big-eared bats, during the winter months of 2010 to 2012. We tested the hypothesis that Rafinesque's big-eared bats use torpor less often than values reported for other North American cave-hibernators. Additionally, we tested the hypothesis that Rafinesque's big-eared bats arouse on winter nights more suitable for nocturnal foraging. Radio-tagged bats used short (2.4 d ± 0.3 (SE, shallow (13.9°C ± 0.6 torpor bouts and switched roosts every 4.1 d ± 0.6. Probability of arousal from torpor increased linearly with ambient temperature at sunset (P<0.0001, and 83% (n=86 of arousals occurred within 1 hr of sunset. Activity of PIT-tagged bats at an artificial maternity/hibernaculum roost between November and March was positively correlated with ambient temperature at sunset (P<0.0001, with males more active at the roost than females. These data show Rafinesque's big-eared bat is a shallow hibernator and is relatively active during winter. We hypothesize that winter activity patterns provide Corynorhinus species with an ecological and physiological defense against the fungus causing WNS, and that these bats may be better suited to withstand fungal infection than other cave-hibernating bat species in eastern North America.

  19. Preliminary signs of the initiation of deep convection by GNSS

    Directory of Open Access Journals (Sweden)

    H. Brenot

    2013-06-01

    Full Text Available This study reports on the exploitation of GNSS (Global Navigation Satellite System and a new potential application for weather forecasts and nowcasting. We focus on GPS observations (post-processing with a time resolution of 5 and 15 min and fast calculations with a time resolution of 5 min and try to establish typical configurations of the water vapour field which characterise convective systems and particularly which supply precursors of their initiation are associated with deep convection. We show the critical role of GNSS horizontal gradients of the water vapour content to detect small scale structures of the troposphere (i. e. convective cells, and then we present our strategy to obtain typical water vapour configurations by GNSS called "H2O alert". These alerts are based on a dry/wet contrast taking place during a 30 min time window before the initiation of a convective system. GNSS observations have been assessed for the rainfall event of 28–29 June 2005 using data from the Belgian dense network (baseline from 5 to 30 km. To validate our GNSS H2O alerts, we use the detection of precipitation by C-band weather radar and thermal infrared radiance (cloud top temperature of the 10.8-micrometers channel [Ch09] of SEVIRI instrument on Meteosat Second Generation. Using post-processed measurements, our H2O alerts obtain a score of about 80%. Final and ultra-rapid IGS (International GNSS Service orbits have been tested and show equivalent results. Fast calculations (less than 10 min have been processed for 29 June 2005 with a time resolution of 5 min. The mean bias (and standard deviation between fast and reference post-processed ZTD (zenith total delay and gradients are, respectively, 0.002 (± 0.008 m and 0.001 (± 0.004 m. The score obtained for the H2O alerts generated by fast calculations is 65%.

  20. Preliminary signs of the initiation of deep convection by GNSS

    Science.gov (United States)

    Brenot, H.; Neméghaire, J.; Delobbe, L.; Clerbaux, N.; De Meutter, P.; Deckmyn, A.; Delcloo, A.; Frappez, L.; Van Roozendael, M.

    2013-06-01

    This study reports on the exploitation of GNSS (Global Navigation Satellite System) and a new potential application for weather forecasts and nowcasting. We focus on GPS observations (post-processing with a time resolution of 5 and 15 min and fast calculations with a time resolution of 5 min) and try to establish typical configurations of the water vapour field which characterise convective systems and particularly which supply precursors of their initiation are associated with deep convection. We show the critical role of GNSS horizontal gradients of the water vapour content to detect small scale structures of the troposphere (i. e. convective cells), and then we present our strategy to obtain typical water vapour configurations by GNSS called "H2O alert". These alerts are based on a dry/wet contrast taking place during a 30 min time window before the initiation of a convective system. GNSS observations have been assessed for the rainfall event of 28-29 June 2005 using data from the Belgian dense network (baseline from 5 to 30 km). To validate our GNSS H2O alerts, we use the detection of precipitation by C-band weather radar and thermal infrared radiance (cloud top temperature) of the 10.8-micrometers channel [Ch09] of SEVIRI instrument on Meteosat Second Generation. Using post-processed measurements, our H2O alerts obtain a score of about 80%. Final and ultra-rapid IGS (International GNSS Service) orbits have been tested and show equivalent results. Fast calculations (less than 10 min) have been processed for 29 June 2005 with a time resolution of 5 min. The mean bias (and standard deviation) between fast and reference post-processed ZTD (zenith total delay) and gradients are, respectively, 0.002 (± 0.008) m and 0.001 (± 0.004) m. The score obtained for the H2O alerts generated by fast calculations is 65%.

  1. In-the-Ear Hearing-Instrument Antenna for ISM-Band Body-Centric Ear-to-Ear Communications

    DEFF Research Database (Denmark)

    Yatman, William H.; Larsen, Lauge K; Kvist, Søren Helstrup

    2012-01-01

    A compact 2.45 GHz slot-loop antenna is implemented for the use in the outer shell of an in-the-ear (ITE) hearing instrument (HI). The antenna is optimized for high ear-to-ear path gain (jS21j). The antenna simulation results are presented for two identical antennas, one placed in the center of e...

  2. Interconnections between the Ears in Nonmammalian Vertebrates

    DEFF Research Database (Denmark)

    Feng, Albert S.; Christensen-Dalsgaard, J.

    2010-01-01

    Many of the nonmammalian vertebrates (anurans, lizards, crocodiles, and some bird species) have large, continuous air spaces connecting the middle ears and acoustically coupling the eardrums. Acoustical coupling leads to strongly enhanced directionality of the ear at frequencies where diffraction...

  3. Physiological functioning of the ear and masking

    Science.gov (United States)

    1984-01-01

    The physiological functions of the ear and the role masking plays in speech communication are examined. Topics under investigation include sound analysis of the ear, the aural reflex, and various types of noise masking.

  4. Feasibility Study of Using Mobile Laser Scanning Point Cloud Data for GNSS Line of Sight Analysis

    Directory of Open Access Journals (Sweden)

    Yuwei Chen

    2017-01-01

    Full Text Available The positioning accuracy with good GNSS observation can easily reach centimetre level, supported by advanced GNSS technologies. However, it is still a challenge to offer a robust GNSS based positioning solution in a GNSS degraded area. The concept of GNSS shadow matching has been proposed to enhance the GNSS based position accuracy in city canyons, where the nearby high buildings block parts of the GNSS radio frequency (RF signals. However, the results rely on the accuracy of the utilized ready-made 3D city model. In this paper, we investigate a solution to generate a GNSS shadow mask with mobile laser scanning (MLS cloud data. The solution includes removal of noise points, determining the object which only attenuated the RF signal and extraction of the highest obstruction point, and eventually angle calculation for the GNSS shadow mask generation. By analysing the data with the proposed methodology, it is concluded that the MLS point cloud data can be used to extract the GNSS shadow mask after several steps of processing to filter out the hanging objects and the plantings without generating the accurate 3D model, which depicts the boundary of GNSS signal coverage more precisely in city canyon environments compared to traditional 3D models.

  5. Performance Analysis of Two-Dimensional Dead Reckoning Based on Vehicle Dynamic Sensors during GNSS Outages

    Directory of Open Access Journals (Sweden)

    Joong-hee Han

    2017-01-01

    Full Text Available Recently, to improve safety and convenience in driving, numerous sensors are mounted on cars to operate advanced driver assistant systems. Among various sensors, vehicle dynamic sensors can measure the vehicle motions such as speed and rotational angular speed for dead reckoning, which can be applied to develop a land vehicle positioning system to overcome the weaknesses of the GNSS technique. In this paper, three land vehicle positioning algorithms that integrate GNSS with vehicle dynamic sensors including a wheel speed sensor (WSS, a yaw rate sensor (YRS, and a steering angle sensor (SAS are implemented, and then a performance evaluation was conducted during GNSS outages. Using a loosely coupled strategy, three integration algorithms are designed, namely, GNSS/WSS, GNSS/WSS/YRS, and GNSS/WSS/YRS/SAS. The performance of the three types of integration algorithm is evaluated based on two data sets. The results indicate that both the GNSS/WSS/YRS integration and the GNSS/WSS/YRS/SAS integration could estimate the horizontal position with meter-level accuracy during 30-second GNSS outages. However, the GNSS/WSS integration would provide an unstable navigation solution during GNSS outages due to the accuracy limitation of the computed yaw rate using WSS.

  6. COMMON INFECTIONS OF THE EAR

    African Journals Online (AJOL)

    Enrique

    steroid/anti-fungal/antibiotic. (e.g. Kenacomb) ear pack if severe. Bacterial. Severe pain. Oedema with occlusion. Swimming. Ichthammol glycerin, combination ... oral medication.2. Benefits of antibiotic treatment for otitis media. A Cochrane review of antibiotics for acute otitis media in children showed no reduction in pain at ...

  7. Proteomics and the Inner Ear

    Directory of Open Access Journals (Sweden)

    Isolde Thalmann

    2001-01-01

    Full Text Available The inner ear, one of the most complex organs, contains within its bony shell three sensory systems, the evolutionary oldest gravity receptor system, the three semicircular canals for the detection of angular acceleration, and the auditory system - unrivaled in sensitivity and frequency discrimination. All three systems are susceptible to a host of afflictions affecting the quality of life for all of us. In the first part of this review we present an introduction to the milestones of inner ear research to pave the way for understanding the complexities of a proteomics approach to the ear. Minute sensory structures, surrounded by large fluid spaces and a hard bony shell, pose extreme challenges to the ear researcher. In spite of these obstacles, a powerful preparatory technique was developed, whereby precisely defined microscopic tissue elements can be isolated and analyzed, while maintaining the biochemical state representative of the in vivo conditions. The second part consists of a discussion of proteomics as a tool in the elucidation of basic and pathologic mechanisms, diagnosis of disease, as well as treatment. Examples are the organ of Corti proteins OCP1 and OCP2, oncomodulin, a highly specific calcium-binding protein, and several disease entities, Meniere's disease, benign paroxysmal positional vertigo, and perilymphatic fistula.

  8. [Implantable middle ear hearing aids].

    Science.gov (United States)

    à Wengen, D F

    2004-01-01

    Conventional acoustic hearing aids are limited in their performance. Due to physical laws their amplification of sound is limited to within 5 kHz. However, the frequencies between 5 and 10 kHz are essential for understanding consonants. Words can only be understood correctly if their consonants can be understood. Furthermore noise amplification remains a problem with hearing aids. Other problems consist of recurrent infections of the external auditory canal, intolerance for occlusion of the ear canal, feedback noise, and resonances in speech or singing. Implantable middle ear hearing aids like the Soundbridge of Symphonix-Siemens and the MET of Otologics offer improved amplification and a more natural sound. Since the first implantation of a Soundbridge in Switzerland in 1996 almost one thousand patients have been implanted worldwide. The currents systems are semi-implantable. The external audio processor containing the microphone, computer chip, battery and radio system is worn in the hair bearing area behind the ear. Implantation is only considered after unsuccessful fitting of conventional hearing aids. In Switzerland the cost for these implantable hearing aids is covered by social insurances. Initially the cost for an implant is higher than for hearing aids. However, hearing aids need replacement every 5 or 6 years whereas implants will last 20 to 30 years. Due to the superior sound quality and the improved understanding of speech in noise, the number of patients with implantable hearing aids will certainly increase in the next years. Other middle ear implants are in clinical testing.

  9. Mechanics of the frog ear

    NARCIS (Netherlands)

    Van Dijk, Pim; Mason, Matthew J.; Schoffelen, Richard L. M.; Narins, Peter M.; Meenderink, Sebastiaan W. F.

    The frog inner ear contains three regions that are sensitive to airborne sound and which are functionally distinct. (1) The responses of nerve fibres innervating the low-frequency, rostral part of the amphibian papilla (AP) are complex. Electrical tuning of hair cells presumably contributes to the

  10. Method and apparatus for autonomous, in-receiver prediction of GNSS ephemerides

    Science.gov (United States)

    Bar-Sever, Yoaz E. (Inventor); Bertiger, William I. (Inventor)

    2012-01-01

    Methods and apparatus for autonomous in-receiver prediction of orbit and clock states of Global Navigation Satellite Systems (GNSS) are described. Only the GNSS broadcast message is used, without need for periodic externally-communicated information. Earth orientation information is extracted from the GNSS broadcast ephemeris. With the accurate estimation of the Earth orientation parameters it is possible to propagate the best-fit GNSS orbits forward in time in an inertial reference frame. Using the estimated Earth orientation parameters, the predicted orbits are then transformed into Earth-Centered-Earth-Fixed (ECEF) coordinates to be used to assist the GNSS receiver in the acquisition of the signals. GNSS satellite clock states are also extracted from the broadcast ephemeris and a parameterized model of clock behavior is fit to that data. The estimated modeled clocks are then propagated forward in time to enable, together with the predicted orbits, quicker GNSS signal acquisition.

  11. VLBI TRF Combination Using GNSS Software

    Directory of Open Access Journals (Sweden)

    Younghee Kwak

    2013-12-01

    Full Text Available Space geodetic techniques can be used to obtain precise shape and rotation information of the Earth. To achieve this, the representative combination solution of each space geodetic technique has to be produced, and then those solutions need to be combined. In this study, the representative combination solution of very long baseline interferometry (VLBI, which is one of the space geodetic techniques, was produced, and the variations in the position coordinate of each station during 7 years were analyzed. Products from five analysis centers of the International VLBI Service for Geodesy and Astrometry (IVS were used as the input data, and Bernese 5.0, which is the global navigation satellite system (GNSS data processing software, was used. The analysis of the coordinate time series for the 43 VLBI stations indicated that the latitude component error was about 15.6 mm, the longitude component error was about 37.7 mm, and the height component error was about 30.9 mm, with respect to the reference frame, International Terrestrial Reference Frame 2008 (ITRF2008. The velocity vector of the 42 stations excluding the YEBES station showed a magnitude difference of 7.3 mm/yr (30.2% and a direction difference of 13.8° (3.8%, with respect to ITRF2008. Among these, the 10 stations in Europe showed a magnitude difference of 7.8 mm/yr (30.3% and a direction difference of 3.7° (1.0%, while the 14 stations in North America showed a magnitude difference of 2.7 mm/yr (15.8% and a direction difference of 10.3° (2.9%.

  12. Change of guinea pig inner ear pressure by square wave middle ear cavity pressure variation

    NARCIS (Netherlands)

    Feijen, RA; Segenhout, JM; Albers, FWJ; Wit, HP

    The inner ear fluid pressure of guinea pigs was measured during square wave middle ear cavity pressure variation. Time constants were derived for the slopes of the inner ear pressure recovery curves after middle ear pressure change. A "single exponential" function did not fit well and therefore more

  13. Immunologic Disorders of the Inner Ear.

    Science.gov (United States)

    Kinney, William C.; Hughes, Gordon B.

    1997-01-01

    Immune inner ear disease represents a series of immune system mediated problems that can present with hearing loss, dizziness, or both. The etiology, presentation, testing, and treatment of primary immune inner ear disease is discussed. A review of secondary immune inner ear disease is presented for comparison. (Contains references.) (Author/CR)

  14. 21 CFR 878.3590 - Ear prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and... GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An ear prosthesis is a silicone rubber solid device intended to be implanted to reconstruct the external...

  15. Can Loud Music Hurt My Ears?

    Science.gov (United States)

    ... Videos for Educators Search English Español Can Loud Music Hurt My Ears? KidsHealth / For Kids / Can Loud Music Hurt My Ears? Print en español La música ... up? Oh! You want to know if loud music can hurt your ears . Are you asking because ...

  16. Quantum tagging for tags containing secret classical data

    International Nuclear Information System (INIS)

    Kent, Adrian

    2011-01-01

    Various authors have considered schemes for quantum tagging, that is, authenticating the classical location of a classical tagging device by sending and receiving quantum signals from suitably located distant sites, in an environment controlled by an adversary whose quantum information processing and transmitting power is potentially unbounded. All of the schemes proposed elsewhere in the literature assume that the adversary is able to inspect the interior of the tagging device. All of these schemes have been shown to be breakable if the adversary has unbounded predistributed entanglement. We consider here the case in which the tagging device contains a finite key string shared with distant sites but kept secret from the adversary, and show this allows the location of the tagging device to be authenticated securely and indefinitely. Our protocol relies on quantum key distribution between the tagging device and at least one distant site, and demonstrates a new practical application of quantum key distribution. It also illustrates that the attainable security in position-based cryptography can depend crucially on apparently subtle details in the security scenario considered.

  17. A GNSS auroral space weather product-Quantifying auroral effects on GNSS

    Science.gov (United States)

    Mushini, S. C.; Spanswick, E.; Skone, S.; Donovan, E.

    2016-12-01

    Aurora occurs in different well-known morphologies, or types, including the best-known arcs and patchy pulsating aurora (PPA). Previous observational studies have demonstrated that the ionospheric effects of auroral precipitation affect the accuracy of global navigation satellite systems. Hence, there is a need to predict the level of GNSS disruption using auroral information. In an initial attempt to explore this idea, we have used data from a THEMIS (Time History of Events and Macroscale Interactions during Substorms) All-Sky Imagers (ASIs) located at Gillam ( 65.650 geo.mag.lat.) and Fort Smith ( 67.230 geo.mag.lat.). GPS data was also obtained from a Canadian High Arctic Ionospheric Network (CHAIN) GPS receivers collocated with the THEMIS ASIs. This GPS receiver is a commercial GPS scintillation receiver. ASI data and corresponding GPS data for the years 2013-2016 was catalogued in a database. Using this database, relations between scintillation indices and different types of aurora were analyzed. The magnitude of the phase scintillation index (σφ) observed for auroral arcs was much higher than for PPA and correspondingly more cycle slips were observed during auroral arcs compared to PPA. We have also analyzed spectral slopes for all events during auroral arcs and patchy aurora. Although the histograms for these spectral indices seem to reveal that average spectral index for both of these phenomena was 1.75, spectral indices for auroral arcs seem to tend towards higher values compared to spectral indices of PPA. Distribution of average brightness around the satellite's IPP, during PPA and arcs were also considered in this study. "Nowcast" GNSS user disruption statistical model is under development.

  18. A Method of Detections’ Fusion for GNSS Anti-Spoofing

    Directory of Open Access Journals (Sweden)

    Huiqi Tao

    2016-12-01

    Full Text Available The spoofing attack is one of the security threats of systems depending on the Global Navigation Satellite System (GNSS. There have been many GNSS spoofing detection methods, and each of them focuses on a characteristic of the GNSS signal or a measurement that the receiver has obtained. The method based on a single detector is insufficient against spoofing attacks in some scenarios. How to fuse multiple detections together is a problem that concerns the performance of GNSS anti-spoofing. Scholars have put forward a model to fuse different detection results based on the Dempster-Shafer theory (DST of evidence combination. However, there are some problems in the application. The main challenge is the valuation of the belief function, which is a key issue in DST. This paper proposes a practical method of detections’ fusion based on an approach to assign the belief function for spoofing detections. The frame of discernment is simplified, and the hard decision of hypothesis testing is replaced by the soft decision; then, the belief functions for some detections can be evaluated. The method is discussed in detail, and a performance evaluation is provided, as well. Detections’ fusion reduces false alarms of detection and makes the result more reliable. Experimental results based on public test datasets demonstrate the performance of the proposed method.

  19. by monitoring microgravity and GPS/GNSS methods

    Indian Academy of Sciences (India)

    Dokuz Eylul University, Department of Geophysical Engineering, Tınaztepe Campus, Buca, Izmir, Turkey. ∗. Corresponding author. e-mail: .... For processing GPS/GNSS data, the software, which is called GAMIT/GLOBK (Herring 2009; .... trend for DEU6, DEU7, DEU8, DEU5, DEU11 measurement points (uplift), stable for ...

  20. On User Algorithms for GNSS Precise Point Positioning

    NARCIS (Netherlands)

    De Bakker, P.F.

    2016-01-01

    Precise Point Positioning (PPP) is a Global Navigation Satellite System (GNSS) processing method with the objective of providing high positioning accuracy without the need for a nearby base station or dense network of reference stations operated by the user. To reach this objective, PPP uses the

  1. A Method of Detections' Fusion for GNSS Anti-Spoofing.

    Science.gov (United States)

    Tao, Huiqi; Li, Hong; Lu, Mingquan

    2016-12-19

    The spoofing attack is one of the security threats of systems depending on the Global Navigation Satellite System (GNSS). There have been many GNSS spoofing detection methods, and each of them focuses on a characteristic of the GNSS signal or a measurement that the receiver has obtained. The method based on a single detector is insufficient against spoofing attacks in some scenarios. How to fuse multiple detections together is a problem that concerns the performance of GNSS anti-spoofing. Scholars have put forward a model to fuse different detection results based on the Dempster-Shafer theory (DST) of evidence combination. However, there are some problems in the application. The main challenge is the valuation of the belief function, which is a key issue in DST. This paper proposes a practical method of detections' fusion based on an approach to assign the belief function for spoofing detections. The frame of discernment is simplified, and the hard decision of hypothesis testing is replaced by the soft decision; then, the belief functions for some detections can be evaluated. The method is discussed in detail, and a performance evaluation is provided, as well. Detections' fusion reduces false alarms of detection and makes the result more reliable. Experimental results based on public test datasets demonstrate the performance of the proposed method.

  2. GNSS Spoofing Detection and Mitigation Based on Maximum Likelihood Estimation.

    Science.gov (United States)

    Wang, Fei; Li, Hong; Lu, Mingquan

    2017-06-30

    Spoofing attacks are threatening the global navigation satellite system (GNSS). The maximum likelihood estimation (MLE)-based positioning technique is a direct positioning method originally developed for multipath rejection and weak signal processing. We find this method also has a potential ability for GNSS anti-spoofing since a spoofing attack that misleads the positioning and timing result will cause distortion to the MLE cost function. Based on the method, an estimation-cancellation approach is presented to detect spoofing attacks and recover the navigation solution. A statistic is derived for spoofing detection with the principle of the generalized likelihood ratio test (GLRT). Then, the MLE cost function is decomposed to further validate whether the navigation solution obtained by MLE-based positioning is formed by consistent signals. Both formulae and simulations are provided to evaluate the anti-spoofing performance. Experiments with recordings in real GNSS spoofing scenarios are also performed to validate the practicability of the approach. Results show that the method works even when the code phase differences between the spoofing and authentic signals are much less than one code chip, which can improve the availability of GNSS service greatly under spoofing attacks.

  3. Acquisition of GNSS signals in urban interference environment

    NARCIS (Netherlands)

    Wildemeersch, Matthias; Wildemeersch, Matthias; Slump, Cornelis H.; Rabbachin, Alberto

    2014-01-01

    In urban environment Global Navigation Satellite System (GNSS) signals are impaired by strong fading and by the presence of several potential sources of interference that can severely affect the acquisition. The work presented here evaluates the acquisition performance for the most common

  4. Influence of Ionospheric Irregularities on GNSS Remote Sensing

    Directory of Open Access Journals (Sweden)

    M. V. Tinin

    2015-01-01

    Full Text Available We have used numerical simulation to study the effects of ionospheric irregularities on accuracy of global navigation satellite system (GNSS measurements, using ionosphere-free (in atmospheric research and geometry-free (in ionospheric research dual-frequency phase combinations. It is known that elimination of these effects from multifrequency GNSS measurements is handi-capped by diffraction effects during signal propagation through turbulent ionospheric plasma with the inner scale being smaller than the Fresnel radius. We demonstrated the possibility of reducing the residual ionospheric error in dual-frequency GNSS remote sensing in ionosphere-free combination by Fresnel inversion. The inversion parameter, the distance to the virtual screen, may be selected from the minimum of amplitude fluctuations. This suggests the possibility of improving the accuracy of GNSS remote sensing in meteorology. In the study of ionospheric disturbances with the aid of geometry-free combination, the Fresnel inversion eliminates only the third-order error. To eliminate the random TEC component which, like the measured average TEC, is the first-order correction, we should use temporal filtering (averaging.

  5. Carcinoid tumour of the middle ear

    LENUS (Irish Health Repository)

    Baig, Salman

    2012-09-01

    A case of middle ear mass in a young female from Ireland is described, who presented with left ear hearing loss and intermittent bloody discharge from the same ear. Examination under microscope revealed occlusive polyp in the left ear and a biopsy had been taken under general anaesthesia. Histopathology report described an adenoma \\/ carcinoid tumour of the middle ear confirmed by positive immunohistochemical staining. CT temporal bones revealed the extension of the disease. The patient underwent left tympanotomy and excision of the tumour. In general, these tumours are regarded as benign but may be mistaken for adenocarcinomas because of their histological heterogenecity.

  6. USGS GNSS Applications to Volcano Disaster Response and Hazard Mitigation

    Science.gov (United States)

    Lisowski, M.; McCaffrey, R.

    2015-12-01

    Volcanic unrest is often identified by increased rates of seismicity, deformation, or the release of volcanic gases. Deformation results when ascending magma accumulates in crustal reservoirs, creates new pathways to the surface, or drains from magma reservoirs to feed an eruption. This volcanic deformation is overprinted by deformation from tectonic processes. GNSS monitoring of volcanoes captures transient volcanic deformation and steady and transient tectonic deformation, and we use the TDEFNODE software to unravel these effects. We apply the technique on portions of the Cascades Volcanic arc in central Oregon and in southern Washington that include a deforming volcano. In central Oregon, the regional TDEFNODE model consists of several blocks that rotate and deform internally and a decaying inflationary volcanic pressure source to reproduce the crustal bulge centered ~5 km west of South Sister. We jointly invert 47 interferograms that cover the interval from 1992 to 2010, as well as 2001 to 2015 continuous GNSS (cGNSS) and survey-mode (sGNSS) time series from stations in and around the Three Sisters, Newberry, and Crater Lake areas. A single, smoothly-decaying ~5 km deep spherical or prolate spheroid volcanic pressure source activated around 1998 provides the best fit to the combined geodetic data. In southern Washington, GNSS displacement time-series track decaying deflation of a ~8 km deep magma reservoir that fed the 2004 to 2008 eruption of Mount St. Helens. That deformation reversed when it began to recharge after the eruption ended. Offsets from slow slip events on the Cascadia subduction zone punctuate the GNSS displacement time series, and we remove them by estimating source parameters for these events. This regional TDEFNODE model extends from Mount Rainier south to Mount Hood, and additional volcanic sources could be added if these volcanoes start deforming. Other TDEFNODE regional models are planned for northern Washington (Mount Baker and Glacier

  7. Establishment of Karadeniz Technical University Permanent GNSS Station as Reactivated of TRAB IGS Station

    Science.gov (United States)

    Kazancı, Selma Zengin; Kayıkçı, Emine Tanır

    2017-12-01

    In recent years, Global Navigation Satellite Systems (GNSS) have gained great importance in terms of the benefi ts it provides such as precise geodetic point positioning, determining crustal deformations, navigation, vehicle monitoring systems and meteorological applications etc. As in Turkey, for this purpose, each country has set up its own GNSS station networks like Turkish National Permanent RTK Network analyzed precise station coordinates and velocities together with the International GNSS Service, Turkish National Fundamental GPS Network and Turkish National Permanent GNSS Network (TNPGN) stations not only are utilized as precise positioning but also GNSS meteorology studies so total number of stations are increased. This work is related to the reactivated of the TRAB IGS station which was established in Karadeniz Technical University, Department of Geomatics Engineering. Within the COST ES1206 Action (GNSS4SWEC) KTU analysis center was established and Trop-NET system developed by Geodetic Observatory Pecny (GOP, RIGTC) in order to troposphere monitoring. The project titled "Using Regional GNSS Networks to Strengthen Severe Weather Prediction" was accepted to the scientifi c and technological research council of Turkey (TUBITAK). With this project, we will design 2 new constructed GNSS reference station network. Using observation data of network, we will compare water vapor distribution derived by GNSS Meteorology and GNSS Tomography. At this time, KTU AC was accepted as E-GVAP Analysis Centre in December 2016. KTU reference station is aimed to be a member of the EUREF network with these studies.

  8. Study of GNSS Loss of Lock Characteristics under Ionosphere Scintillation with GNSS Data at Weipa (Australia) During Solar Maximum Phase.

    Science.gov (United States)

    Liu, Yang; Fu, Lianjie; Wang, Jinling; Zhang, Chunxi

    2017-09-25

    One of the adverse impacts of scintillation on GNSS signals is the loss of lock status, which can lead to GNSS geometry and visibility reductions that compromise the accuracy and integrity of navigation performance. In this paper the loss of lock based on ionosphere scintillation in this solar maximum phase has been well investigated with respect to both temporal and spatial behaviors, based on GNSS observatory data collected at Weipa (Australia; geographic: 12.45° S, 130.95° E; geomagnetic: 21.79° S, 214.41° E) from 2011 to 2015. Experiments demonstrate that the percentage of occurrence of loss of lock events under ionosphere scintillation is closely related with solar activity and seasonal shifts. Loss of lock behaviors under ionosphere scintillation related to elevation and azimuth angles are statistically analyzed, with some distinct characteristics found. The influences of daytime scintillation and geomagnetic storms on loss of lock have also been discussed in details. The proposed work is valuable for a deeper understanding of theoretical mechanisms of-loss of lock under ionosphere scintillation in global regions, and provides a reference for GNSS applications in certain regions at Australian low latitudes.

  9. The War of Jenkins' Ear.

    Science.gov (United States)

    Graboyes, Evan M; Hullar, Timothy E

    2013-02-01

    In 1731, Spanish sailors boarded the British brig Rebecca off the coast of Cuba and sliced off the left ear of its captain, Robert Jenkins. This traumatic auriculectomy was used as a pretext by the British to declare war on Spain in 1739, a conflict that is now known as the War of Jenkins' Ear. Here, we examine the techniques available for auricular repair at the time of Jenkins' injury and relate them to the historical events surrounding the incident. Review of relevant original published manuscripts and monographs. Surgeons in the mid-18th century did not have experience with repair of traumatic total auriculectomies. Some contemporary surgeons favored auricular prostheses over surgical treatment. METHODS for the reconstruction of partial defects were available, and most authors advocated a local post-auricular flap instead of a free tissue transfer. Techniques for repair of defects of the auricle lagged behind those for repair of the nose. Limitations in care of traumatic auricular defects may have intensified the significance of Jenkins' injury and helped lead to the War of Jenkins' Ear, but conflict between Britain and Spain was probably unavoidable because of their conflicting commercial interests in the Caribbean. (C) 2013 Otology & Neurotology, Inc.

  10. The War of Jenkins’ Ear

    Science.gov (United States)

    Graboyes, Evan M.; Hullar, Timothy E.

    2012-01-01

    Objective In 1731, Spanish sailors boarded the British brig Rebecca off the coast of Cuba and sliced off the left ear of its captain, Robert Jenkins. This traumatic auriculectomy was used as a pretext by the British to declare war on Spain in 1739, a conflict that is now known as the War of Jenkins’ Ear. Here, we examine the techniques available for auricular repair at the time of Jenkins’ injury and relate them to the historical events surrounding the incident. Methods Review of relevant original published manuscripts and monographs. Results Surgeons in the mid-18th century did not have experience with repair of traumatic total auriculectomies. Some contemporary surgeons favored auricular prostheses over surgical treatment. Methods for the reconstruction of partial defects were available, and most authors advocated a local post-auricular flap instead of a free tissue transfer. Techniques for repair of defects of the auricle lagged behind those for repair of the nose. Conclusion Limitations in care of traumatic auricular defects may have intensified the significance of Jenkins’ injury and helped lead to the War of Jenkins’ Ear, but conflict between Britain and Spain was probably unavoidable due to their conflicting commercial interests in the Caribbean. PMID:23444484

  11. Editorial Tag Endogeneity for News Websites

    OpenAIRE

    Bruno Ribeiro; Ricardo Morla; Amílcar Correia

    2013-01-01

    Editors and journalists at some news websites label their articles with structure and content-related editorial tags. Each article can have more than one tag and each tag can be used in more than one article. A network of tags can be defined whose edges are all possible pairs of tags in each article. Because editorial tags relate to structure and content rather than individual articles, the analysis of a network of editorial tags could assist editorial decisions to prioritize types of content...

  12. THE PERFORMANCE OF A TIGHT INS/GNSS/PHOTOGRAMMETRIC INTEGRATION SCHEME FOR LAND BASED MMS APPLICATIONS IN GNSS DENIED ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    C.-H. Chu

    2016-06-01

    Full Text Available The early development of mobile mapping system (MMS was restricted to applications that permitted the determination of the elements of exterior orientation from existing ground control. Mobile mapping refers to a means of collecting geospatial data using mapping sensors that are mounted on a mobile platform. Research works concerning mobile mapping dates back to the late 1980s. This process is mainly driven by the need for highway infrastructure mapping and transportation corridor inventories. In the early nineties, advances in satellite and inertial technology made it possible to think about mobile mapping in a different way. Instead of using ground control points as references for orienting the images in space, the trajectory and attitude of the imager platform could now be determined directly. Cameras, along with navigation and positioning sensors are integrated and mounted on a land vehicle for mapping purposes. Objects of interest can be directly measured and mapped from images that have been georeferenced using navigation and positioning sensors. Direct georeferencing (DG is the determination of time-variable position and orientation parameters for a mobile digital imager. The most common technologies used for this purpose today are satellite positioning using the Global Navigation Satellite System (GNSS and inertial navigation using an Inertial Measuring Unit (IMU. Although either technology used along could in principle determine both position and orientation, they are usually integrated in such a way that the IMU is the main orientation sensor, while the GNSS receiver is the main position sensor. However, GNSS signals are obstructed due to limited number of visible satellites in GNSS denied environments such as urban canyon, foliage, tunnel and indoor that cause the GNSS gap or interfered by reflected signals that cause abnormal measurement residuals thus deteriorates the positioning accuracy in GNSS denied environments. This study aims

  13. Tempting To Tag: An Experimental Comparison Of Four Tagging Input Mechanisms

    Directory of Open Access Journals (Sweden)

    Mark Melenhorst

    2010-01-01

    Full Text Available Tagging helps achieve improved indexing and recommendation of resources (e.g., videos or pictures in large data collections. In order to reap the benefits of tagging, people must be persuaded to label the resources they consume. This paper reports on a study in which four different tagging input mechanisms and their effect on users' motivation to tag were compared. The mechanisms consisted of a standard tag input box, a chatbot-like environment, a bookmarking mechanism, and a "tag and vote" game. The results of our experiment show that the use of the nonstandard tagging input mechanisms does not affect users' motivation to tag. In some instances tagging mechanisms were found to distract users from their primary task: consuming resources. Persuading people to tag might be accomplished more effectively by using other motivating tagging mechanisms (e.g., tagging games, or motivation could be created by explaining the usefulness of tagging.

  14. Evaluation of Tag Attachments on Small Cetaceans

    Science.gov (United States)

    2013-09-30

    tag on the dorsal fin trailing edge. Dr. Randall Wells of CZS managed the project and coordinated tag production and field tests. All of these...modeling demonstrated that horizontally oriented tags created significantly less drag than vertically oriented tags. Undesirable turbulence was identified...successfully calved in 2013. Follow-up assessments in July found no indication of health problems associated with the tags. The anti-fouling

  15. An SDR-based Study of Multi-GNSS Positioning Performance During Fast-developing Space Weather Storm

    Directory of Open Access Journals (Sweden)

    Mia Filic

    2016-09-01

    Full Text Available The understanding of the ionospheric effects on GNSS positioning performance forms an essential pre-requisite for resilient GNSS development. Here we present the results of a study of the effects of a fast-developing space weather disturbance on the positioning performance of a commercial-grade GPS+GLONASS receiver. Using experimentally collected pseudoranges and the RTKLIB, an open-source software-defined GNSS radio receiver operating in the simulation mode, we assessed GNSS positioning performance degradations for various modes of GNSS SDR receiver operation, and identified the benefits of utilisation of multi-GNSS and ionospheric error correction techniques.

  16. GNSS Buoy Array in the Ocean for Natural Hazard Mitigation

    Science.gov (United States)

    Kato, T.; Terada, Y.; Yamamoto, S. I.; Iwakiri, N.; Toyoshima, M.; Koshikawa, N.; Motohashi, O.; Hashimoto, G.; Wada, A.

    2015-12-01

    The GNSS buoy system for tsunami early warning has been developed in Japan. The system has been implemented as a national wave monitoring system and its record was used to update the tsunami warning at the 3.11 Tohoku-oki earthquake. The lessons learned in this experience was that the buoys are placed only less than 20km from the coast, which was not far enough for effective evacuation of people. We thus tried to improve the system for putting the buoy much farther from the coast. First, we tried to implement, different from current baseline mode RTK-GPS, a real-time PPP analysis strategy for positioning. In addition, we tried to use a two-way satellite data transmission in contrast with current surface radio system. We have made a series of experiments for this purpose in 2013 and 2014. A buoy of about 40km south of Shikoku, southwest Japan, was used for this purpose. GEONET data were used to obtain precise orbits and clocks of satellites. Then, the information was transferred to the GNSS buoy using LEX signal of QZSS satellite system. The received information on the buoy were used for real-time PPP analysis for every second. The obtained buoy position was then transmitted to the ground base, through an engineering test satellite, ETS-VIII. The received data was then disseminated to public through the internet. Both filtered short-term and long-term waves, were separately shown on the webpage. The success of these experiments indicates that the GNSS buoy can be placed at least more than 1,500 km from the ground based tracking network. Given this success, we would now be able to deploy a new GNSS buoy array system in the wide ocean. An array in the ocean can be used for ionospheric and atmospheric research in the same region as well as tsunami or ocean bottom crustal deformation monitoring through an application to the GNSS-acoustic system. We are now designing a regional GNSS buoy array in the western Pacific as a synthetic natural hazard mitigation system.

  17. Precise Point Positioning Using Triple GNSS Constellations in Various Modes

    Directory of Open Access Journals (Sweden)

    Akram Afifi

    2016-05-01

    Full Text Available This paper introduces a new dual-frequency precise point positioning (PPP model, which combines the observations from three different global navigation satellite system (GNSS constellations, namely GPS, Galileo, and BeiDou. Combining measurements from different GNSS systems introduces additional biases, including inter-system bias and hardware delays, which require rigorous modelling. Our model is based on the un-differenced and between-satellite single-difference (BSSD linear combinations. BSSD linear combination cancels out some receiver-related biases, including receiver clock error and non-zero initial phase bias of the receiver oscillator. Forming the BSSD linear combination requires a reference satellite, which can be selected from any of the GPS, Galileo, and BeiDou systems. In this paper three BSSD scenarios are tested; each considers a reference satellite from a different GNSS constellation. Natural Resources Canada’s GPSPace PPP software is modified to enable a combined GPS, Galileo, and BeiDou PPP solution and to handle the newly introduced biases. A total of four data sets collected at four different IGS stations are processed to verify the developed PPP model. Precise satellite orbit and clock products from the International GNSS Service Multi-GNSS Experiment (IGS-MGEX network are used to correct the GPS, Galileo, and BeiDou measurements in the post-processing PPP mode. A real-time PPP solution is also obtained, which is referred to as RT-PPP in the sequel, through the use of the IGS real-time service (RTS for satellite orbit and clock corrections. However, only GPS and Galileo observations are used for the RT-PPP solution, as the RTS-IGS satellite products are not presently available for BeiDou system. All post-processed and real-time PPP solutions are compared with the traditional un-differenced GPS-only counterparts. It is shown that combining the GPS, Galileo, and BeiDou observations in the post-processing mode improves the

  18. Precise Point Positioning Using Triple GNSS Constellations in Various Modes.

    Science.gov (United States)

    Afifi, Akram; El-Rabbany, Ahmed

    2016-05-28

    This paper introduces a new dual-frequency precise point positioning (PPP) model, which combines the observations from three different global navigation satellite system (GNSS) constellations, namely GPS, Galileo, and BeiDou. Combining measurements from different GNSS systems introduces additional biases, including inter-system bias and hardware delays, which require rigorous modelling. Our model is based on the un-differenced and between-satellite single-difference (BSSD) linear combinations. BSSD linear combination cancels out some receiver-related biases, including receiver clock error and non-zero initial phase bias of the receiver oscillator. Forming the BSSD linear combination requires a reference satellite, which can be selected from any of the GPS, Galileo, and BeiDou systems. In this paper three BSSD scenarios are tested; each considers a reference satellite from a different GNSS constellation. Natural Resources Canada's GPSPace PPP software is modified to enable a combined GPS, Galileo, and BeiDou PPP solution and to handle the newly introduced biases. A total of four data sets collected at four different IGS stations are processed to verify the developed PPP model. Precise satellite orbit and clock products from the International GNSS Service Multi-GNSS Experiment (IGS-MGEX) network are used to correct the GPS, Galileo, and BeiDou measurements in the post-processing PPP mode. A real-time PPP solution is also obtained, which is referred to as RT-PPP in the sequel, through the use of the IGS real-time service (RTS) for satellite orbit and clock corrections. However, only GPS and Galileo observations are used for the RT-PPP solution, as the RTS-IGS satellite products are not presently available for BeiDou system. All post-processed and real-time PPP solutions are compared with the traditional un-differenced GPS-only counterparts. It is shown that combining the GPS, Galileo, and BeiDou observations in the post-processing mode improves the PPP convergence

  19. Innovative Remote Sensing: Flood Monitoring using GNSS Reflectometry

    Science.gov (United States)

    Beckheinrich, Jamila; Hirrle, Angelika; Schön, Steffen; Beyerle, Georg; Semmling, Maximillian; Apel, Heiko; Wickert, Jens

    2014-05-01

    An increase of the intensity and frequency of extreme precipitation events are observed in the last decade due to climate changing conditions. Resulting floods pose significant socio-economic problems in areas like on the banks of the Mekong Delta with dense population. To quantify and predict the impact of these flooding events to the local population it is important to measure and understand the related hydrological processes. Satellite based altimetry offers water level measurements with high accuracy for oceans and very large rivers but typically with insufficient spatio-temporal resolution. The accuracy decreases in coastal areas. Water level gauging instruments offer a high accuracy and temporal resolution but for a single location only. However, the number of water level gauging stations worldwide is decreasing. GNSS-Reflectometry (GNSS-R) can fill the gap between these two measurement methods. Earth reflected L-band signals from the Global Navigation Satellite Systems (GNSS) show a high reflectivity on water surfaces. This property is used to derive water level height changes. In principle two different GNSS-R altimetry methods exist: based on code or carrier phase observations. Our research activities focus on the phase-based altimetric application of GNSS-R. In March 2012, a two-week measurement campaign was conducted in Can Tho City, Vietnam within the WISDOM (Water related Information System for the sustainable Development Of the Mekong Delta) research project. Several reflection traces on the 150 m wide Can Tho River section are recorded with a dedicated GNSS-R receiver developed in cooperation between GFZ and JAVAD. To track the direct and the reflected signal separately, two antennas are used. The analysis of the recorded signals shows a superposition of the signal reflected by the water surface with other multipath signals. These occur due to the surrounding of the antennas (vegetation, buildings). To separate these different multipath signals and

  20. Neutral B meson flavor tagging

    CERN Document Server

    Wilson, R J

    2001-01-01

    We present an investigation of the use of net charge and kaon identification to tag the flavor of neutral B mesons. The net charge of the neutral B meson decay products is zero if all charged particles are used and slightly non-zero if only undiscriminated hadronic final states are used. The net charge of the kaons alone correctly tags the identity of the neutral meson in at least a third of all decays. We have parametrized the particle identification capability of several techniques, such as dE/dx in time projection chambers, LEP/SLC ring-imaging chambers and an enhanced BaBar DIRC. Using these parametrisations we compare the relative tagging power of each technique to that of an ideal detector. (8 refs).

  1. Tracking Clouds with low cost GNSS chips aided by the Arduino platform

    Science.gov (United States)

    Hameed, Saji; Realini, Eugenio; Ishida, Shinya

    2016-04-01

    The Global Navigation Satellite System (GNSS) is a constellation of satellites that is used to provide geo-positioning services. Besides this application, the GNSS system is important for a wide range of scientific and civilian applications. For example, GNSS systems are routinely used in civilian applications such as surveying and scientific applications such as the study of crustal deformation. Another important scientific application of GNSS system is in meteorological research. Here it is mainly used to determine the total water vapour content of the troposphere, hereafter Precipitable Water Vapor (PWV). However, both GNSS receivers and software have prohibitively high price due to a variety of reasons. To overcome this somewhat artificial barrier we are exploring the use of low-cost GNSS receivers along with open source GNSS software for scientific research, in particular for GNSS meteorology research. To achieve this aim, we have developed a custom Arduino compatible data logging board that is able to operate together with a specific low-cost single frequency GNSS receiver chip from NVS Technologies AG. We have also developed an open-source software bundle that includes a new Arduino core for the Atmel324p chip, which is the main processor used in our custom logger. We have also developed software code that enables data collection, logging and parsing of the GNSS data stream. Additionally we have comprehensively evaluated the low power characteristics of the GNSS receiver and logger boards. Currently we are exploring the use of several openly source or free to use for research software to map GNSS delays to PWV. These include the open source goGPS (http://www.gogps-project.org/) and gLAB (http://gage.upc.edu/gLAB) and the openly available GAMIT software from Massachusetts Institute of Technology (MIT). We note that all the firmware and software developed as part of this project is available on an open source license.

  2. Sensibility of the ear after otoplasty.

    Science.gov (United States)

    Coltro, Pedro Soler; Alves, Hélio R N; Gallafrio, Samuel T; Busnardo, Fábio F; Ferreira, Marcus C

    2012-02-01

    Changes in skin sensibility occur in various postoperative plastic surgeries, especially when they involve major skin and subcutaneous dissection. There were no studies so far that objectively compared changes of ear sensibility. This prospective study was conducted to compare ear sensibility before and after otoplasty. Patients with prominent ears (n = 15) underwent bilateral otoplasty. Ear tactile sensibility was tested preoperatively and 6 and 12 months after surgery by Pressure Specified Sensory Device, an apparatus that quantifies cutaneous pressure sensation (g/mm(2)). Comparison between preoperative and 6-months postoperative results indicated an increment on mean skin pressure thresholds; however, mean thresholds between pre- and 12 months postoperative period were similar. Vibratory and hot/cold sensibility did not present any difference during this period. This is the first comparative assessment of ear tactile sensibility using quantitative methods. After otoplasty, initially there was reduction in an ear tactile sensibility, followed by a return to levels similar to preoperative sensibility.

  3. WebTag: Web browsing into sensor tags over NFC.

    Science.gov (United States)

    Echevarria, Juan Jose; Ruiz-de-Garibay, Jonathan; Legarda, Jon; Alvarez, Maite; Ayerbe, Ana; Vazquez, Juan Ignacio

    2012-01-01

    Information and Communication Technologies (ICTs) continue to overcome many of the challenges related to wireless sensor monitoring, such as for example the design of smarter embedded processors, the improvement of the network architectures, the development of efficient communication protocols or the maximization of the life cycle autonomy. This work tries to improve the communication link of the data transmission in wireless sensor monitoring. The upstream communication link is usually based on standard IP technologies, but the downstream side is always masked with the proprietary protocols used for the wireless link (like ZigBee, Bluetooth, RFID, etc.). This work presents a novel solution (WebTag) for a direct IP based access to a sensor tag over the Near Field Communication (NFC) technology for secure applications. WebTag allows a direct web access to the sensor tag by means of a standard web browser, it reads the sensor data, configures the sampling rate and implements IP based security policies. It is, definitely, a new step towards the evolution of the Internet of Things paradigm.

  4. WebTag: Web Browsing into Sensor Tags over NFC

    Directory of Open Access Journals (Sweden)

    Juan Jose Echevarria

    2012-06-01

    Full Text Available Information and Communication Technologies (ICTs continue to overcome many of the challenges related to wireless sensor monitoring, such as for example the design of smarter embedded processors, the improvement of the network architectures, the development of efficient communication protocols or the maximization of the life cycle autonomy. This work tries to improve the communication link of the data transmission in wireless sensor monitoring. The upstream communication link is usually based on standard IP technologies, but the downstream side is always masked with the proprietary protocols used for the wireless link (like ZigBee, Bluetooth, RFID, etc.. This work presents a novel solution (WebTag for a direct IP based access to a sensor tag over the Near Field Communication (NFC technology for secure applications. WebTag allows a direct web access to the sensor tag by means of a standard web browser, it reads the sensor data, configures the sampling rate and implements IP based security policies. It is, definitely, a new step towards the evolution of the Internet of Things paradigm.

  5. A REVIEW ON LEGAL TRACEABILITY OF GNSS MEASUREMENTS IN THE MALAYSIAN CADASTRAL PRACTICE

    Directory of Open Access Journals (Sweden)

    J. Gill

    2016-09-01

    Full Text Available As the dependency on Global Navigation Satellite System (GNSS in surveying has been growing over the years, the need for legal traceability of GNSS measurements has become a significant matter. In Malaysia, with the advent of the Malaysia Real-time Kinematic Network (MyRTKnet, GNSS surveying has revolutionised land survey and mapping. Correspondingly, the Department of Survey and Mapping Malaysia (DSMM amended and published standard regulations and guidelines concerning cadastral survey, i.e., Cadastral Survey Regulations 2009, to include GNSS measurements. However, these regulations and guidelines has not comprehensively incorporated legal traceability of GNSS measurements; which is a prerequisite for cadastral surveys as it requires reliable and conclusive evidence for issues such as boundary disputes. The first objective of this paper is to review and discuss the legal traceability of GNSS measurements. Secondly, it will highlight the current practice and issues, i.e., with regard to legal traceability, within the present Malaysian cadastral regulation and guidelines, in relation to the prevalently adopted Network RTK (N-RTK technique, GNSS instrument calibrations, and reference stations’ accuracy. Lastly, a rudimentary best practice guideline for GNSS surveying in cadastral survey for Malaysia is proposed. It is expected that this paper will contribute to the implementation of a best practice guideline, which is inclusive of legal traceability of GNSS measurements, for the Malaysian cadastral practice.

  6. The inertial attitude augmentation for ambiguity resolution in SF/SE-GNSS attitude determination.

    Science.gov (United States)

    Zhu, Jiancheng; Hu, Xiaoping; Zhang, Jingyu; Li, Tao; Wang, Jinling; Wu, Meiping

    2014-06-26

    The Unaided Single Frequency/Single Epoch Global Navigation Satellite System (SF/SE GNSS) model is the most challenging scenario for ambiguity resolution in the GNSS attitude determination application. To improve the performance of SF/SE-GNSS ambiguity resolution without excessive cost, the Micro-Electro-Mechanical System Inertial Measurement Unit (MEMS-IMU) is a proper choice for the auxiliary sensor that carries out the inertial attitude augmentation. Firstly, based on the SF/SE-GNSS compass model, the Inertial Derived Baseline Vector (IDBV) is defined to connect the MEMS-IMU attitude measurement with the SF/SE-GNSS ambiguity search space, and the mechanism of inertial attitude augmentation is revealed from the perspective of geometry. Then, through the quantitative description of model strength by Ambiguity Dilution of Precision (ADOP), two ADOPs are specified for the unaided SF/SE-GNSS compass model and its inertial attitude augmentation counterparts, respectively, and a sufficient condition is proposed for augmenting the SF/SE-GNSS model strength with inertial attitude measurement. Finally, in the framework of an integer aperture estimator with fixed failure rate, the performance of SF/SE-GNSS ambiguity resolution with inertial attitude augmentation is analyzed when the model strength is varying from strong to weak. The simulation results show that, in the SF/SE-GNSS attitude determination application, MEMS-IMU can satisfy the requirements of ambiguity resolution with inertial attitude augmentation.

  7. Comparing Global Positioning System (GPS) and Global Navigation Satellite System (GNSS) Measures of Team Sport Movements.

    Science.gov (United States)

    Jackson, Benjamin M; Polglaze, Ted; Dawson, Brian; King, Trish; Peeling, Peter

    2018-02-21

    To compare data from conventional GPS and new GNSS-enabled tracking devices, and to examine the inter-unit reliability of GNSS devices. Inter-device differences between 10 Hz GPS and GNSS devices were examined during laps (n=40) of a simulated game circuit (SGC) and during elite hockey matches (n=21); GNSS inter-unit reliability was also examined during the SGC laps. Differences in distance values and measures in three velocity categories (low 5 m.s -1 ) and acceleration/deceleration counts (>1.46 m.s -2 and GNSS reliability was examined using the coefficient of variation (CV) and intra-class correlation coefficient (ICC). Inter-device differences (P GNSS) differences (P GNSS devices had a lower HDoP score than GPS devices in all conditions. These findings suggest that GNSS devices may be more sensitive than GPS in quantifying the physical demands of team sport movements, but further study into the accuracy of GNSS devices is required.

  8. Molecular Mechanisms of Inner Ear Development

    OpenAIRE

    Wu, Doris K.; Kelley, Matthew W.

    2012-01-01

    The inner ear is a structurally complex vertebrate organ built to encode sound, motion, and orientation in space. Given its complexity, it is not surprising that inner ear dysfunction is a relatively common consequence of human genetic mutation. Studies in model organisms suggest that many genes currently known to be associated with human hearing impairment are active during embryogenesis. Hence, the study of inner ear development provides a rich context for understanding the functions of gen...

  9. [Rhabdomyosarcoma of the middle ear].

    Science.gov (United States)

    El Fehri, F; Salih-Alj, A; Kzadri, M; Zemmama, M; Alaoui, B H; Jazouli, N

    1982-01-01

    A seven year old boy was admitted with what appeared to be polyp of the external auditory canal, otitis media and Bell's palsy. It was subsequently diagnosed as rhabdomyosarcoma of the middle ear. This rare tumor must not be out of mind of practitioners, and especially pediatricians and E.N.T. specialists, when they have to examine a child with what looks like chronic otitis media, and aural polyp, or idiopathic facial paralysis. The diagnosis is histological and must be quickly made for early and aggressive multimodal antitumor therapy, which seems to be improving the hitherto gloomy prognosis for these highly lethal sarcoma.

  10. Challenges and Opportunities of GNSS Reference Station Network

    Directory of Open Access Journals (Sweden)

    JIANG Weiping

    2017-10-01

    Full Text Available GNSS(Global Navigation Satellite System reference station network is not only an important infrastructure to provide national, regional and global high-precision time and space datum, but also is an important support for navigation and location services, precise satellite orbit determination, geological disaster monitoring and other scientific and technological applications. At present, with the increase of reference station network of continuously operating reference system (CORS and the rapid establishment of BeiDou, the development of the networks is facing many opportunities and challenges. Firstly, this paper gives the definition and classification of the GNSS reference station network, and describes its function and significance. And then the history and present situation of development of the network are analyzed. Finally, we discuss the challenges and opportunities of the network based on its establishment, data processing theory and method, application.

  11. Code Single Point Positioning Using Nominal GNSS Constellations (Future Perception)

    Science.gov (United States)

    Farah, A. M. A.

    Global Navigation Satellite Systems (GNSS) have an endless number of applications in industry, science, military, transportation and recreation & sports. Two systems are currently in operation, namely GPS (the USA Global Positioning System) and GLONASS (the Russian GLObal NAvigation Satellite System), and a third is planned, the European satellite navigation system GALILEO. The potential performance improvements achievable through combining these systems could be significant and expectations are high. The need is inevitable to explore the future of positioning from different nominal constellations. In this research paper, Bernese 5.0 software could be modified to simulate and process GNSS observations from three different constellations (GPS, GLONASS and Galileo) using different combinations. This study presents results of code single point positioning for five stations using the three constellations and different combinations.

  12. CT of the ear in Pendred syndrome.

    Science.gov (United States)

    Goldfeld, Moshe; Glaser, Benjamin; Nassir, Elias; Gomori, John Moshe; Hazani, Elitsur; Bishara, Nassir

    2005-05-01

    To prospectively determine the structural anomalies of the inner ear by using thin-section computed tomography (CT) in an extended family with Pendred syndrome. Ethics committee approved the study, and informed consent was obtained from every patient or from parents of patients under legal age. Twelve patients (three females and nine males aged 7-47 years) with Pendred syndrome (all from the same ethnic isolate and with the same mutation in the PDS gene) were evaluated for inner-ear malformation at thin-section CT. Both ears were evaluated. Presence or absence of interscalar septum between upper and middle turns of the cochlea was evaluated, and vestibule and vestibular aqueduct were examined for enlargement. Modiolus was determined to be present or absent (modiolar deficiency). CT scans were evaluated in consensus by two radiologists (M.G., J.M.G.). All patients had inner ear malformation on both sides. Modiolus was absent and vestibule was enlarged on both sides in all 12 patients. Interscalar septum was absent in 18 (75%) of 24 ears. In eight patients, interscalar septum was absent in both ears, whereas in two patients, it was absent on only one side. Aqueduct was enlarged in 20 (80%) of 24 ears. In nine patients, both ears had enlarged aqueducts, while in two patients, only one side was abnormal. Inner ear malformation is an invariable finding in Pendred syndrome. Modiolus deficiency and vestibular enlargement were the most consistent anomalies in this population with Pendred syndrome. (c) RSNA, 2005.

  13. Molecular mechanisms of inner ear development.

    Science.gov (United States)

    Wu, Doris K; Kelley, Matthew W

    2012-08-01

    The inner ear is a structurally complex vertebrate organ built to encode sound, motion, and orientation in space. Given its complexity, it is not surprising that inner ear dysfunction is a relatively common consequence of human genetic mutation. Studies in model organisms suggest that many genes currently known to be associated with human hearing impairment are active during embryogenesis. Hence, the study of inner ear development provides a rich context for understanding the functions of genes implicated in hearing loss. This chapter focuses on molecular mechanisms of inner ear development derived from studies of model organisms.

  14. Onboard Train Localization with Track Signatures: Towards GNSS Redundancy

    OpenAIRE

    Heirich, Oliver; Siebler, Benjamin

    2017-01-01

    Future railway applications, such as train-side collision avoidance, virtual coupling or autonomous train driving demand reliable and accurate train localization. We focus on exclusive onboard train localization without additional way-side infrastructure. Common approaches for onboard train localization are based on measurements of a global satellite navigation system (GNSS). Well-known methods for improved reliability and accuracy are the combination with inertial navigation systems...

  15. Dependency of geodynamic parameters on the GNSS constellation

    Science.gov (United States)

    Scaramuzza, Stefano; Dach, Rolf; Beutler, Gerhard; Arnold, Daniel; Sušnik, Andreja; Jäggi, Adrian

    2018-01-01

    Significant differences in time series of geodynamic parameters determined with different Global Navigation Satellite Systems (GNSS) exist and are only partially explained. We study whether the different number of orbital planes within a particular GNSS contributes to the observed differences by analyzing time series of geocenter coordinates (GCCs) and pole coordinates estimated from several real and virtual GNSS constellations: GPS, GLONASS, a combined GPS/GLONASS constellation, and two virtual GPS sub-systems, which are obtained by splitting up the original GPS constellation into two groups of three orbital planes each. The computed constellation-specific GCCs and pole coordinates are analyzed for systematic differences, and their spectral behavior and formal errors are inspected. We show that the number of orbital planes barely influences the geocenter estimates. GLONASS' larger inclination and formal errors of the orbits seem to be the main reason for the initially observed differences. A smaller number of orbital planes may lead, however, to degradations in the estimates of the pole coordinates. A clear signal at three cycles per year is visible in the spectra of the differences between our estimates of the pole coordinates and the corresponding IERS 08 C04 values. Combinations of two 3-plane systems, even with similar ascending nodes, reduce this signal. The understanding of the relation between the satellite constellations and the resulting geodynamic parameters is important, because the GNSS currently under development, such as the European Galileo and the medium Earth orbit constellation of the Chinese BeiDou system, also consist of only three orbital planes.

  16. NASA Global GNSS Network (GGN) Status and Plans

    Science.gov (United States)

    Doelger, S.; Sklar, J.; Blume, F.; Meertens, C. M.; Mattioli, G. S.

    2015-12-01

    UNAVCO, in conjunction with JPL, is responsible for monitoring the 62 GNSS permanent stations, which include 88 GPS receivers, which comprise the NASA Global GNSS Network (GGN). These sites represent approximately 16% of the ~400 International GNSS Service (IGS) stations, and they provide a globally distributed GNSS network to support NASA operations and its commitments to GGOS. UNAVCO provides data flow monitoring, trouble-shooting, station installation, maintenance, as well as engineering services to improve the capabilities and performance of station infrastructure. Activities this past year include the installation of a geodetic quality wellhead monument for the new SEY2 station to replace SEY1, which is mounted on a UCSD seismic station in the Seychelles Islands. SEY1 will be removed soon to accommodate planned maintenance and upgrades by UCSD. Data from both SEY1 and SEY2 are being collected concurrently until maintenance begins. MRTG (Multi Router Traffic Grapher), a tool to aid in characterizing bandwidth usage and to identify communications problems, is now being used to monitor data throughput at 7 stations where VSAT or radio telemetry are used, including: ABPO; AREQ; FALK; GUAM; HARV; ISPA; QUIN; and STHL. Aging computers are being replaced with new hardware running Linux CentOS. These are semi-ruggedized low power solid-state systems built to endure challenging environments. With the aid of on-site collaborators, systems are now deployed at: FALK; CUSV; KELY; STHL; SANT; and ZAMB. Last, 4 new GPS stations were deployed for NASA's Space Geodesy Project (SGP); three of which (KOKF, KOKG, and KOKR) are located at Koke'e Park Geophysical Observatory on Kauai, Hawai'i, and HAL1 at the Haleakala observatory complex on Maui, Hawai'i. A campaign system was set up at Koke'e in order to sample data quality to determine if an additional station would be viable. Planning is ongoing for deployment of several new stations next year at McDonald Observatory (TX).

  17. CSAC Characterization and Its Impact on GNSS Clock Augmentation Performance

    Directory of Open Access Journals (Sweden)

    Enric Fernández

    2017-02-01

    Full Text Available Chip Scale Atomic Clocks (CSAC are recently-developed electronic instruments that, when used together with a Global Navigation Satellite Systems (GNSS receiver, help improve the performance of GNSS navigation solutions in certain conditions (i.e., low satellite visibility. Current GNSS receivers include a Temperature Compensated Cristal Oscillator (TCXO clock characterized by a short-term stability (τ = 1 s of 10−9 s that leads to an error of 0.3 m in pseudorange measurements. The CSAC can achieve a short-term stability of 2.5 × 10−12 s, which implies a range error of 0.075 m, making for an 87.5% improvement over TCXO. Replacing the internal TCXO clock of GNSS receivers with a higher frequency stability clock such as a CSAC oscillator improves the navigation solution in terms of low satellite visibility positioning accuracy, solution availability, signal recovery (holdover, multipath and jamming mitigation and spoofing attack detection. However, CSAC suffers from internal systematic instabilities and errors that should be minimized if optimal performance is desired. Hence, for operating CSAC at its best, the deterministic errors from the CSAC need to be properly modelled. Currently, this modelling is done by determining and predicting the clock frequency stability (i.e., clock bias and bias rate within the positioning estimation process. The research presented in this paper aims to go a step further, analysing the correlation between temperature and clock stability noise and the impact of its proper modelling in the holdover recovery time and in the positioning performance. Moreover, it shows the potential of fine clock coasting modelling. With the proposed model, an improvement in vertical positioning precision of around 50% with only three satellites can be achieved. Moreover, an increase in the navigation solution availability is also observed, a reduction of holdover recovery time from dozens of seconds to only a few can be achieved.

  18. CSAC Characterization and Its Impact on GNSS Clock Augmentation Performance.

    Science.gov (United States)

    Fernández, Enric; Calero, David; Parés, M Eulàlia

    2017-02-14

    Chip Scale Atomic Clocks (CSAC) are recently-developed electronic instruments that, when used together with a Global Navigation Satellite Systems (GNSS) receiver, help improve the performance of GNSS navigation solutions in certain conditions (i.e., low satellite visibility). Current GNSS receivers include a Temperature Compensated Cristal Oscillator (TCXO) clock characterized by a short-term stability ( τ = 1 s) of 10 -9 s that leads to an error of 0.3 m in pseudorange measurements. The CSAC can achieve a short-term stability of 2.5 × 10 -12 s, which implies a range error of 0.075 m, making for an 87.5% improvement over TCXO. Replacing the internal TCXO clock of GNSS receivers with a higher frequency stability clock such as a CSAC oscillator improves the navigation solution in terms of low satellite visibility positioning accuracy, solution availability, signal recovery (holdover), multipath and jamming mitigation and spoofing attack detection. However, CSAC suffers from internal systematic instabilities and errors that should be minimized if optimal performance is desired. Hence, for operating CSAC at its best, the deterministic errors from the CSAC need to be properly modelled. Currently, this modelling is done by determining and predicting the clock frequency stability (i.e., clock bias and bias rate) within the positioning estimation process. The research presented in this paper aims to go a step further, analysing the correlation between temperature and clock stability noise and the impact of its proper modelling in the holdover recovery time and in the positioning performance. Moreover, it shows the potential of fine clock coasting modelling. With the proposed model, an improvement in vertical positioning precision of around 50% with only three satellites can be achieved. Moreover, an increase in the navigation solution availability is also observed, a reduction of holdover recovery time from dozens of seconds to only a few can be achieved.

  19. 21 CFR 874.3430 - Middle ear mold.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food... DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is intended to be implanted to reconstruct the middle ear...

  20. Influence of Ionospheric Weather on GNSS Radio Occultation Signals

    Science.gov (United States)

    Yue, X.; Schreiner, W. S.; Pedatella, N. M.; Kuo, Y. H.

    2016-12-01

    Transient loss of lock (LOL) is one of the key space weather effects on the Global Navigation Satellite System (GNSS). Based on the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) Global Positioning System (GPS) radio occultation (RO) observations during 2007-2011, we have analyzed the signal cycle slip (CS) occurrence comprehensively and its correlation to the ionospheric weather phenomena such as sporadic E (Es), equatorial F region irregularity (EFI), and the ionospheric equatorial ionization anomaly (EIA). The high vertical resolution of RO observations enables us to distinguish the CS resulting from different ionospheric layers clearly on a global scale. In the E layer, the CS is dominated by the Es occurrence, while in the F layer, the CS is mainly related to the EIA and EFI at low and equatorial latitudes. In the polar region, the CS is primarily related to polar cap electron density gradients. The overall average CS (> 6 cycles) occurrence is 23% per occultation, with the E (50-150 km) and F (150-600 km) layers contributing 8.3% and 14.7%, respectively. Awareness of the effect of the ionospheric weather on the CS of the low-Earth-orbit (LEO)-based GNSS signal could be beneficial to a variety of applications, including the LEO-based GNSS data processing and the corresponding hardware/firmware design.

  1. INVESTIGATION OF THE AIR QUALITY CHANGE EFFECT ON GNSS SIGNALS

    Directory of Open Access Journals (Sweden)

    G. Gurbuz

    2017-11-01

    Full Text Available Air pollution is the most important environmental problem in Zonguldak city center. Since bituminous coal is used for domestic heating in houses and generating electricity in thermal power plants, particulate matter (PM10 is the leading air pollutant. Previous studies have shown that the water vapor in the troposphere is responsible for the tropospheric zenith delay in Global Navigation Satellite System (GNSS measurements. In this study, data obtained from the ZONG GNSS station from Türkiye Ulusal Sabit GNSS Ağı (TUSAGA-Active network in the central district of Zonguldak province, processed with GIPSY-OASIS II and GAMIT/GlobK software using the VMF1 mapping function, which is developed previously and considered to be the most accurate model. The resulting values were examined separately in terms of software. The meteorological parameters obtained from the Turkish State Meteorological Service and the air pollution values obtained from the Ministry of Environment and Urban Planning were analyzed and the zenith delay values were compared. When wet zenith delays of different days with different amounts of PM10 concentrations were examined in succession and under the same meteorological conditions, differences in the range of 20–40 mm on ZTD were observed.

  2. Investigation of the Air Quality Change Effect on Gnss Signals

    Science.gov (United States)

    Gurbuz, G.; Gormus, K. S.; Altan, U.

    2017-11-01

    Air pollution is the most important environmental problem in Zonguldak city center. Since bituminous coal is used for domestic heating in houses and generating electricity in thermal power plants, particulate matter (PM10) is the leading air pollutant. Previous studies have shown that the water vapor in the troposphere is responsible for the tropospheric zenith delay in Global Navigation Satellite System (GNSS) measurements. In this study, data obtained from the ZONG GNSS station from Türkiye Ulusal Sabit GNSS Ağı (TUSAGA-Active network) in the central district of Zonguldak province, processed with GIPSY-OASIS II and GAMIT/GlobK software using the VMF1 mapping function, which is developed previously and considered to be the most accurate model. The resulting values were examined separately in terms of software. The meteorological parameters obtained from the Turkish State Meteorological Service and the air pollution values obtained from the Ministry of Environment and Urban Planning were analyzed and the zenith delay values were compared. When wet zenith delays of different days with different amounts of PM10 concentrations were examined in succession and under the same meteorological conditions, differences in the range of 20-40 mm on ZTD were observed.

  3. Quantifying Visual-Representativeness of Social Image Tags Using Image Tag Clarity

    Science.gov (United States)

    Sun, Aixin; Bhowmick, Sourav S.

    Tags associated with images in various social media sharing web sites are valuable information source for superior image retrieval experiences. Due to the nature of tagging, many tags associated with images are not visually descriptive. In this chapter, we propose Image Tag Clarity to evaluate the effectiveness of a tag in describing the visual content of its annotated images, which is also known as the image tag visual-representativeness. It is measured by computing the zero-mean normalized distance between the tag language model estimated from the images annotated by the tag and the collection language model. The tag/collection language models are derived from the bag of visual-word local content features of the images. The visual-representative tags that are commonly used to annotate visually similar images are given high tag clarity scores. Evaluated on a large real-world dataset containing more than 269K images and their associated tags, we show that the image tag clarity score can effectively identify the visual-representative tags from all tags contributed by users. Based on the tag clarity scores, we have made a few interesting observations that could be used to support many tag-based applications.

  4. An SDR-based Study of Multi-GNSS Positioning Performance During Fast-developing Space Weather Storm

    OpenAIRE

    Mia Filic; Renato Filjar; Laura Ruotsalainen

    2016-01-01

    The understanding of the ionospheric effects on GNSS positioning performance forms an essential pre-requisite for resilient GNSS development. Here we present the results of a study of the effects of a fast-developing space weather disturbance on the positioning performance of a commercial-grade GPS+GLONASS receiver. Using experimentally collected pseudoranges and the RTKLIB, an open-source software-defined GNSS radio receiver operating in the simulation mode, we assessed GNSS positioning perf...

  5. Continuous Fine-Fault Estimation with Real-Time GNSS

    Science.gov (United States)

    Norford, B. B.; Melbourne, T. I.; Szeliga, W. M.; Santillan, V. M.; Scrivner, C.; Senko, J.; Larsen, D.

    2017-12-01

    Thousands of real-time telemetered GNSS stations operate throughout the circum-Pacific that may be used for rapid earthquake characterization and estimation of local tsunami excitation. We report on the development of a GNSS-based finite-fault inversion system that continuously estimates slip using real-time GNSS position streams from the Cascadia subduction zone and which is being expanded throughout the circum-Pacific. The system uses 1 Hz precise point position streams computed in the ITRF14 reference frame using clock and satellite orbit corrections from the IGS. The software is implemented as seven independent modules that filter time series using Kalman filters, trigger and estimate coseismic offsets, invert for slip using a non-negative least squares method developed by Lawson and Hanson (1974) and elastic half-space Green's Functions developed by Okada (1985), smooth the results temporally and spatially, and write the resulting streams of time-dependent slip to a RabbitMQ messaging server for use by downstream modules such as tsunami excitation modules. Additional fault models can be easily added to the system for other circum-Pacific subduction zones as additional real-time GNSS data become available. The system is currently being tested using data from well-recorded earthquakes including the 2011 Tohoku earthquake, the 2010 Maule earthquake, the 2015 Illapel earthquake, the 2003 Tokachi-oki earthquake, the 2014 Iquique earthquake, the 2010 Mentawai earthquake, the 2016 Kaikoura earthquake, the 2016 Ecuador earthquake, the 2015 Gorkha earthquake, and others. Test data will be fed to the system and the resultant earthquake characterizations will be compared with published earthquake parameters. Seismic events will be assumed to occur on major faults, so, for example, only the San Andreas fault will be considered in Southern California, while the hundreds of other faults in the region will be ignored. Rake will be constrained along each subfault to be

  6. Climatology of GNSS ionospheric scintillation at high latitudes

    Science.gov (United States)

    Spogli, L.; Alfonsi, L.; de Franceschi, G.; Romano, V.; Aquino, M.; Dodson, A.; Mitchell, C. N.

    2009-12-01

    Under perturbed conditions caused by intense solar wind magnetosphere coupling, the ionosphere may become highly turbulent and irregularities, typically enhancements or depletions of the electron density embedded in the ambient ionosphere, can form. Such irregularities cause diffraction effects, mainly due to the random fluctuations of the refractive index of the ionosphere, on the satellites signals passing through them and consequent perturbations may cause GNSS navigation errors and outages, abruptly corrupting its performance. Due to the morphology of the geomagnetic field, whose lines are almost vertical at high latitude, polar areas are characterized by the presence of significant ionospheric irregularities having scale sizes ranging from hundreds of kilometers down to a few centimeters and with highly dynamic structures. The understanding of the effect of such phenomena is important, not only in preparation for the next solar cycle (24), whose maximum is expected in 2012, but also for a deeper comprehension of the dynamics of the high-latitude ionosphere. We analyze the fluctuations in the carrier frequency of the radio waves received on the ground, commonly referred to as ionospheric amplitude and phase scintillations, to investigate the physical processes causing them. The phase scintillations on GNSS signals are likely caused by ionospheric irregularities of scale size of hundreds of meters to few kilometers. The amplitude scintillations on GNSS signals are caused by ionospheric irregularities of scale size smaller than the Fresnel radius, which is of the order of hundreds of meters for GNSS signals, typically embedded into the patches. The Istituto Nazionale di Geofisica e Vulcanologia (INGV) and the Institute of Engineering Surveying and Space Geodesy (IESSG) of the University of Nottingham manage the same kind of GISTM (GPS Ionospheric Scintillation and TEC Monitor) receivers over the European high and mid latitude regions and over Antarctica. The

  7. HMSRP Hawaiian Monk Seal Tag Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records for all tags applied to Hawaiian monk seals since 1981. These tags were applied by PSD personnel and cooperating scientists as part of...

  8. Satellite Tags- Guam/CNMI EEZ

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Satellite tagging was implemented in 2013. Satellite tagging is conducted using a Dan Inject air rifle and deployment arrows designed by Wildlife Computers. Two...

  9. A Novel Security Method For RFID Tags

    Directory of Open Access Journals (Sweden)

    Imran Ali Jokhio

    2012-07-01

    Full Text Available RFID (Radio Frequency Identification tags use light weighted security methods because of cost constraints. In this paper a lightweight security method is investigated and proved that it significantly lacks in protecting RFID tags against simple cloning attack. In order to protect RFID tag from cloning attacks a novel security method is proposed in this paper. The proposed security method provides high level computational difficulty against the three basic attacking techniques, i.e. eavesdropping, replay and man in the middle. In order to clone a tag, attacker eavesdrops the tag responses and creates a replica of the tag. The novel security method presented in this paper increases the hardness to avoid guessing tag secrets resulting in a conditional none clone able tags. The proposed security method is also evaluated using propositional logic proofs to demonstrate the level of security it can provide.

  10. The Complex Dynamics of Collaborative Tagging

    NARCIS (Netherlands)

    H. Halpin; V. Robu (Valentin); H. Shepherd

    2007-01-01

    textabstractThe debate within the Web community over the optimal means by which to organize information often pits formalized classifications against distributed collaborative tagging systems. A number of questions remain unanswered, however, regarding the nature of collaborative tagging systems

  11. Single-baseline RTK GNSS Positioning for Hydrographic Surveying

    Science.gov (United States)

    Metin Alkan, Reha; Murat Ozulu, I.; Ilçi, Veli; Kahveci, Muzaffer

    2015-04-01

    Positioning with GNSS technique can be carried out in two ways, absolute and relative. It has been possible to reach a few meters absolute point positioning accuracies in real time after disabling SA permanently in May 2000. Today, accuracies obtainable from absolute point positioning using code observations are not sufficient for most surveying applications. Thus to meet higher accuracy requirements, differential methods using single or dual frequency geodetic-grade GNSS receivers that measure carrier phase have to be used. However, this method requires time-cost field and office works and if the measurement is not carried out with conventional RTK method, user needs a GNSS data processing software to estimate the coordinates. If RTK is used, at least two or more GNSS receivers are required, one as a reference and the other as a rover. Moreover, the distance between the receivers must not exceed 15-20 km in order to be able to rapidly and reliably resolve the carrier phase ambiguities. On the other hand, based on the innovations and improvements in satellite geodesy and GNSS modernization studies occurred within the last decade, many new positioning methods and new approaches have been developed. One of them is Network-RTK (or commonly known as CORS) and the other is Single-baseline RTK. These methods are widely used for many surveying applications in many countries. The user of the system can obtain his/her position within a few cm level of accuracy in real-time with only a single GNSS receiver that has Network RTK (CORS) capability. When compared with the conventional differential and RTK methods, this technique has several significant advantages as it is easy to use and it produces accurate, cost-effective and rapid solutions. In Turkey, establishment of a multi-base RTK network was completed and opened for civilian use in 2009. This network is called CORS-TR and consists of 146 reference stations having about 80-100 km interstation distances. It is possible

  12. Towards two identification methods for breeding pigs: possibilities of a combined ear tag

    NARCIS (Netherlands)

    Lokhorst, C.; Hogewerf, P.H.; Hoofs, A.I.J.; Verheijen, R.; Ipema, A.H.

    2012-01-01

    The objective of this study is to develop a reliable, practical and affordable combined farm and slaughter identification for Dutch breeding pigs (sows and boars) before 1 January 2012. In consultation with representatives of pig farmers, breeding institutions, traders, slaughterhouses and

  13. Playing by Ear: Foundation or Frill?

    Science.gov (United States)

    Woody, Robert H.

    2012-01-01

    Many people divide musicians into two types: those who can read music and those who play by ear. Formal music education tends to place great emphasis on producing musically literate performers but devotes much less attention to teaching students to make music without notation. Some would suggest that playing by ear is a specialized skill that is…

  14. Congenital malformation of inner ear, single cavity

    International Nuclear Information System (INIS)

    Torres Pazmino, Julio Cesar; Marrugo Pardo, Gilberto Eduardo

    2010-01-01

    Congenital malformations of the inner ear are rare conditions, but their detection requires high diagnostic accuracy. In this report we describe the case of a patient with single or common cavity, discuss the corresponding radiological images, describe the treatment of this patient with a cochlear implant, and review the classification and differential diagnosis of the other anomalies of the inner ear.

  15. Objective Audiometry using Ear-EEG

    DEFF Research Database (Denmark)

    Christensen, Christian Bech; Kidmose, Preben

    Recently, a novel electroencephalographic (EEG) method called ear-EEG [1], that enable recording of auditory evoked potentials (AEPs) from a personalized earpiece was introduced. Initial investigations show that well established AEPs, such as ASSR and P1-N1-P2 complex can be observed from ear-EEG...

  16. The frog inner ear : picture perfect?

    NARCIS (Netherlands)

    Mason, Matthew J.; Segenhout, Johannes M.; Cobo-Cuan, Ariadna; Quiones, Patricia M.; van Dijk, Pim

    Many recent accounts of the frog peripheral auditory system have reproduced Wever's (1973) schematic cross-section of the ear of a leopard frog. We sought to investigate to what extent this diagram is an accurate and representative depiction of the anuran inner ear, using three-dimensional

  17. On Chinese National Continuous Operating Reference Station System of GNSS

    Directory of Open Access Journals (Sweden)

    CHEN Junyong

    2007-11-01

    Full Text Available Objective: Global navigation satellite system (GNSS Continuous Operating Reference Station (CORS System can maintain a accurate, 3D, geocentric and dynamic reference coordinate frame in the corresponding area, can provide positioning and navigation service. It can also serve for the meteorology, geodynamics, earthquake monitoring and Location Based services (LBS etc in the same area. Until now, our country can’t provide a facing National CORS System serving for every profession and trade, and the national sharing platform of CORS System resources has not been established. So this paper discusses some valuable insight how to construct the National CORS System in China. Method: Constructing goal、Service object、CORS distribution、CORS geographic、geology and communication environment and other factors, are major considerations for the Constructing the National CORS System. Moreover, constructing GNSS CORS is more specific, mainly from four aspects, namely site-selection、civil construction、security measures and equipment-selection for consideration. Outcome: The project of the Constructing Global navigation satellite system (GNSS Continuous Operating Reference Station (CORS System in china is put forward, and is discussed from goal、principle、project and other for construction. Some meaning thought how to construct the National CORS System is submitted Conclusion: The Global navigation satellite system (GNSS Continuous Operating Reference Station (CORS System in china is the lack of a unified planning and design in the national level. So far, the national CORS system serving all walks of life has not been provided, and the national sharing platform of CORS System resources has not been established The primary mission of the Global navigation satellite system (GNSS Continuous Operating Reference Station (CORS System in china is as follows: using data set of GNSS and receiving, transport, process, integration, transmit information and

  18. Ear asymmetries in middle-ear, cochlear, and brainstem responses in human infants.

    Science.gov (United States)

    Keefe, Douglas H; Gorga, Michael P; Jesteadt, Walt; Smith, Lynette M

    2008-03-01

    In 2004, Sininger and Cone-Wesson examined asymmetries in the signal-to-noise ratio (SNR) of otoacoustic emissions (OAE) in infants, reporting that distortion-product (DP)OAE SNR was larger in the left ear, whereas transient-evoked (TE)OAE SNR was larger in the right. They proposed that cochlear and brainstem asymmetries facilitate development of brain-hemispheric specialization for sound processing. Similarly, in 2006 Sininger and Cone-Wesson described ear asymmetries mainly favoring the right ear in infant auditory brainstem responses (ABRs). The present study analyzed 2640 infant responses to further explore these effects. Ear differences in OAE SNR, signal, and noise were evaluated separately and across frequencies (1.5, 2, 3, and 4 kHz), and ABR asymmetries were compared with cochlear asymmetries. Analyses of ear-canal reflectance and admittance showed that asymmetries in middle-ear functioning did not explain cochlear and brainstem asymmetries. Current results are consistent with earlier studies showing right-ear dominance for TEOAE and ABR. Noise levels were higher in the right ear for OAEs and ABRs, causing ear asymmetries in SNR to differ from those in signal level. No left-ear dominance for DPOAE signal was observed. These results do not support a theory that ear asymmetries in cochlear processing mimic hemispheric brain specialization for auditory processing.

  19. Improving the GNSS attitude ambiguity success rate with the multivariate constrained LAMBDA method

    NARCIS (Netherlands)

    Giorgi, G.; Teunissen, P.J.G.; Verhagen, S.; Buist, P.J.

    2009-01-01

    GNSS Attitude Determination is a valuable technique for the estimation of platform orientation. To achieve high accuracies on the angular estimations, the GNSS carrier phase data has to be used. These data are known to be affected by integer ambiguities, which must be correctly resolved in order to

  20. Overview of GNSS-R Research Program for Ocean Observations at Japan

    Science.gov (United States)

    Ichikawa, Kaoru; Ebinuma, Takuji; Akiyama, Hiroaki; Kitazawa, Yukihito

    2015-04-01

    GNSS-R is a new remote-sensing method which uses reflected GNSS signals. Since no transmitters are required, it is suitable for small satellites. Constellations of GNSS-R small satellites have abilities on revolutionary progress on 'all-time observable' remote-sensing methods . We have started a research program for GNSS-R applications on oceanographic observations under a contract with MEXT (Ministry of Education Culture, Sports, Science and Technology, JAPAN) as a'Space science research base formation program'. The duration of research program is 3 years (2015-2017). The one of important focuses of this program is creation of a new community to merge space engineering and marine science through establishment on application plans of GNSS-R. Actual GNSS-R data acquisition experiments using multi-copters, ships, and/or towers are planned, together with in-situ sea truth data such as wave spectrum, wind speed profiles and sea surface height. These data are compared to determine the accuracy and resolution of the estimates based on GNSS-R observations. Meanwhile, preparation of a ground station for receiving GNSS-R satellite data will be also established. Whole those data obtained in this project will be distributed for public. This paper introduces the overview of research plan..

  1. New Quality Control Algorithm Based on GNSS Sensing Data for a Bridge Health Monitoring System.

    Science.gov (United States)

    Lee, Jae Kang; Lee, Jae One; Kim, Jung Ok

    2016-05-27

    This research introduces an improvement plan for the reliability of Global Navigation Satellite System (GNSS) positioning solutions. It should be considered the most suitable methodology in terms of the adjustment and positioning of GNSS in order to maximize the utilization of GNSS applications. Though various studies have been conducted with regards to Bridge Health Monitoring System (BHMS) based on GNSS, the outliers which depend on the signal reception environment could not be considered until now. Since these outliers may be connected to GNSS data collected from major bridge members, which can reduce the reliability of a whole monitoring system through the delivery of false information, they should be detected and eliminated in the previous adjustment stage. In this investigation, the Detection, Identification, Adaptation (DIA) technique was applied and implemented through an algorithm. Moreover, it can be directly applied to GNSS data collected from long span cable stayed bridges and most of outliers were efficiently detected and eliminated simultaneously. By these effects, the reliability of GNSS should be enormously improved. Improvement on GNSS positioning accuracy is directly linked to the safety of bridges itself, and at the same time, the reliability of monitoring systems in terms of the system operation can also be increased.

  2. Global Ionospheric Modelling using Multi-GNSS: BeiDou, Galileo, GLONASS and GPS.

    Science.gov (United States)

    Ren, Xiaodong; Zhang, Xiaohong; Xie, Weiliang; Zhang, Keke; Yuan, Yongqiang; Li, Xingxing

    2016-09-15

    The emergence of China's Beidou, Europe's Galileo and Russia's GLONASS satellites has multiplied the number of ionospheric piercing points (IPP) offered by GPS alone. This provides great opportunities for deriving precise global ionospheric maps (GIMs) with high resolution to improve positioning accuracy and ionospheric monitoring capabilities. In this paper, the GIM is developed based on multi-GNSS (GPS, GLONASS, BeiDou and Galileo) observations in the current multi-constellation condition. The performance and contribution of multi-GNSS for ionospheric modelling are carefully analysed and evaluated. Multi-GNSS observations of over 300 stations from the Multi-GNSS Experiment (MGEX) and International GNSS Service (IGS) networks for two months are processed. The results show that the multi-GNSS GIM products are better than those of GIM products based on GPS-only. Differential code biases (DCB) are by-products of the multi-GNSS ionosphere modelling, the corresponding standard deviations (STDs) are 0.06 ns, 0.10 ns, 0.18 ns and 0.15 ns for GPS, GLONASS, BeiDou and Galileo, respectively in satellite, and the STDs for the receiver are approximately 0.2~0.4 ns. The single-frequency precise point positioning (SF-PPP) results indicate that the ionospheric modelling accuracy of the proposed method based on multi-GNSS observations is better than that of the current dual-system GIM in specific areas.

  3. A comprehensive method for GNSS data quality determination to improve ionospheric data analysis.

    Science.gov (United States)

    Kim, Minchan; Seo, Jiwon; Lee, Jiyun

    2014-08-14

    Global Navigation Satellite Systems (GNSS) are now recognized as cost-effective tools for ionospheric studies by providing the global coverage through worldwide networks of GNSS stations. While GNSS networks continue to expand to improve the observability of the ionosphere, the amount of poor quality GNSS observation data is also increasing and the use of poor-quality GNSS data degrades the accuracy of ionospheric measurements. This paper develops a comprehensive method to determine the quality of GNSS observations for the purpose of ionospheric studies. The algorithms are designed especially to compute key GNSS data quality parameters which affect the quality of ionospheric product. The quality of data collected from the Continuously Operating Reference Stations (CORS) network in the conterminous United States (CONUS) is analyzed. The resulting quality varies widely, depending on each station and the data quality of individual stations persists for an extended time period. When compared to conventional methods, the quality parameters obtained from the proposed method have a stronger correlation with the quality of ionospheric data. The results suggest that a set of data quality parameters when used in combination can effectively select stations with high-quality GNSS data and improve the performance of ionospheric data analysis.

  4. Uniqueness and nonuniqueness of the GNSS carrier-phase compass readings

    NARCIS (Netherlands)

    Teunissen, P.J.G.

    2009-01-01

    In this contribution we analyse the possible nonuniqueness in the least-squares solution of the GNSS carrier-phase compass model. It is shown that this lack of uniqueness may manifest itself in the fixed baseline estimator and therefore in the GNSS compass readings. We present the conditions under

  5. Integrated GNSS attitude determination and positioning for direct geo-referencing

    NARCIS (Netherlands)

    Nadarajah, N.; Paffenholz, J.A.; Teunissen, P.J.G.

    2014-01-01

    Direct geo-referencing is an efficient methodology for the fast acquisition of 3D spatial data. It requires the fusion of spatial data acquisition sensors with navigation sensors, such as Global Navigation Satellite System (GNSS) receivers. In this contribution, we consider an integrated GNSS

  6. ADOP in closed form for a hierarchy of multi-frequency single-baseline GNSS models

    NARCIS (Netherlands)

    Odijk, D.; Teunissen, P.J.G.

    2008-01-01

    Successful carrier phase ambiguity resolution is the key to high-precision positioning with Global Navigation Satellite Systems (GNSS). The ambiguity dilution of precision (ADOP) is a well-known scalar measure which can be used to infer the strength of the GNSS model for carrier phase ambiguity

  7. Contribution of GNSS CORS Infrastructure to the Mission of Modern Geodesy and Status of GNSS CORS in Thailand

    Directory of Open Access Journals (Sweden)

    Chalermchon Satirapod

    2011-01-01

    Full Text Available Geodesy is the science of measuring and mapping the geometry, orientation and gravity field of the Earth including the associated variations with time. Geodesy has also provided the foundation for high accuracy surveying and mapping. Modern Geodesy involves a range of space and terrestrial technologies that contribute to our knowledge of the solid earth, atmosphere and oceans. These technologies include: Global Positioning System/Global Navigation Satellite Systems (GPS/GNSS, Satellite Laser Ranging (SLR, Very Long Baseline Interferometry (VLBI, Satellite Altimetry, Gravity Mapping Missions such as GRACE, CHAMP and GOCE, satelliteborne Differential Interferometric Synthetic Aperture Radar (DInSAR, Absolute and Relative Gravimetry, and Precise Terrestrial Surveying (Levelling and Traversing. A variety of services have been established in recent years to ensure high accuracy and reliable geodetic products to support geoscientific research. The reference frame defined by Modern Geodesy is now the basis for most national and regional datums. Furthermore, the GPS/GNSS technology is a crucial geopositioning tool for both Geodesy and Surveying. There is therefore a blurring of the distinction between geodetic and surveying GPS/GNSS techniques, and increasingly the ground infrastructure of continuously operating reference stations (CORS receivers attempts to address the needs of both geodesists and other positioning professionals. Yet Geodesy is also striving to increase the level of accuracy by a factor of ten over the next decade in order to address the demands of “global change” studies. The Global Geodetic Observing System (GGOS is an important component of the International Association of Geodesy. GGOS aims to integrate all geodetic observations in order to generate a consistent high quality set of geodetic parameters for monitoring the phenomena and processes within the “System Earth”. Integration implies the inclusion of all relevant

  8. Microbiomes of the normal middle ear and ears with chronic otitis media.

    Science.gov (United States)

    Minami, Shujiro B; Mutai, Hideki; Suzuki, Tomoko; Horii, Arata; Oishi, Naoki; Wasano, Koichiro; Katsura, Motoyasu; Tanaka, Fujinobu; Takiguchi, Tetsuya; Fujii, Masato; Kaga, Kimitaka

    2017-10-01

    The aim of this study was to profile and compare the middle ear microbiomes of human subjects with and without chronic otitis media. Prospective multicenter cohort study. All consecutive patients undergoing tympanoplasty surgery for chronic otitis media or ear surgery for conditions other than otitis media were recruited. Sterile swab samples were collected from the middle ear mucosa during surgery. The variable region 4 of the 16S rRNA gene in each sample were amplified using region-specific primers adapted for the Illumina MiSeq sequencer (Illumina, CA, USA)). The sequences were subjected to local blast and classified using Metagenome@KIN (World Fusion, Tokyo, Japan). In total, 155 participants were recruited from seven medical centers. Of these, 88 and 67 had chronic otitis media and normal middle ears, respectively. The most abundant bacterial phyla on the mucosal surfaces of the normal middle ears were Proteobacteria, followed by Actinobacteria, Firmicutes, and Bacteroidetes. The children and adults with normal middle ears differed significantly in terms of middle ear microbiomes. Subjects with chronic otitis media without active inflammation (dry ear) had similar middle ear microbiomes as the normal middle ears group. Subjects with chronic otitis media with active inflammation (wet ear) had a lower prevalence of Proteobacteria and a higher prevalence of Firmicutes than the normal middle ears. The human middle ear is inhabited by more diverse microbial communities than was previously thought. Alteration of the middle ear microbiome may contribute to the pathogenesis of chronic otitis media with active inflammation. 2b. Laryngoscope, 127:E371-E377, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  9. ATLAS boosted object tagging 2

    CERN Document Server

    Caudron, Julien; The ATLAS collaboration

    2015-01-01

    A detailed study into the optimal techniques for identifying boosted hadronically decaying W or Z bosons is presented. Various algorithms for reconstructing, grooming and tagging bosonic jets are compared for W bosons with a wide range of transverse momenta using 8 TeV data and 8 TeV and 13 TeV MC simulations. In addition, given that a hadronic jet has been identified as resulting from the hadronic decay of a W or Z, a technique is developed to discriminate between W and Z bosons. The modeling of the tagging variables used in this technique is studied using 8 TeV pp collision data and systematic uncertainties for the tagger efficiency and fake rates are evaluated.

  10. Overview of new GNSS tropospheric products for GNSS-meteorology and their assessment at Geodetic Observatory Pecny (CZ)

    Science.gov (United States)

    Dousa, J.; Vaclavovic, P.; Gyori, G.

    2012-12-01

    Geodetic Observatory Pecný (GOP) has a long-term experience in the estimation of precise tropospheric parameters from GNSS permanent stations, in particular under the limited timelines of near real time. More than a decade, the GOP zenith total delays (ZTD) contributed to various projects in Europe (COST-716, TOUGH, E-GVAP, E-GVAP II) and the operational ZTD hourly updated product flows via the meteorological observation exchange network - GTS - to the end users worldwide. Currently, the GOP regional ZTD product is operationally assimilated in Météo France and UK MetOffice at least and further exploited in various ways at many other meteorological institutions. New developments at GOP over last three years consist of a) implementation and assessment of the global hourly ZTD product of about 170 stations, b) implementation of routine multi-GNSS (GPS+GLONASS) ZTD European product, and c) implementation of ultra-fast/real-time ZTD product. The GOP global ZTD product has been implemented on request of the meteorological institutions running global numerical weather forecasting models. The global ZTD product was seriously evaluated over ten months (Oct 2009 - Aug 2011) when compared to reprocessed EUREF and IGS ZTDs, radiosondes and ZTDs derived from UK MetOffice's global numerical weather model. After the evaluation (and on special request of UK MetOffice) the product has been switched from testing to operational status within the framework of the EUMETNET EIG GPS Water Vapour Programme (E-GVAP) and officially disseminated via the GTS network. The GOP multi-GNSS ZTD solution has been tested since 2009 shortly after developing GOP ultra-rapid GPS+GLONASS orbits for the International GNSS Service (IGS). A specific bias of mean value 1.5 mm was identified between GPS- and GLONASS-only ZTD at that time, and relation to the IGS05 antenna phase centre offset and variation models (PCO+PCV) identified. Consequently, the implementation of a routine operation has been done

  11. Human and animal ear, comparative anatomy and physiology, literature overview

    OpenAIRE

    Mesarčíková, Zuzana

    2007-01-01

    As used herein, the ear of humans are different things . For some it may najvysunutejšia be only that portion of the auditory system - pinna , for others it is a conversion part of the auditory apparatus - middle ear , and for another group of people is custom ear receptor component of the spirit of the inner - ear . To say nothing of other meanings words ear to ear containers and bags ; chick ear (she praslenitá - sage salvia verticillata , which so fiercely Zháňal witch Saxana ); Judas' ear...

  12. Tag Based Audio Search Engine

    OpenAIRE

    Parameswaran Vellachu; Sunitha Abburu

    2012-01-01

    The volume of the music database is increasing day by day. Getting the required song as per the choice of the listener is a big challenge. Hence, it is really hard to manage this huge quantity, in terms of searching, filtering, through the music database. It is surprising to see that the audio and music industry still rely on very simplistic metadata to describe music files. However, while searching audio resource, an efficient "Tag Based Audio Search Engine" is necessary. The current researc...

  13. Infrared tag and track technique

    Science.gov (United States)

    Partin, Judy K.; Stone, Mark L.; Slater, John; Davidson, James R.

    2007-12-04

    A method of covertly tagging an object for later tracking includes providing a material capable of at least one of being applied to the object and being included in the object, which material includes deuterium; and performing at least one of applying the material to the object and including the material in the object in a manner in which in the appearance of the object is not changed, to the naked eye.

  14. Detection of GNSS Signals Propagation in Urban Canyos Using 3D City Models

    Directory of Open Access Journals (Sweden)

    Petra Pisova

    2015-01-01

    Full Text Available This paper presents one of the solutions to the problem of multipath propagation and effects on Global Navigation Satellite Systems (GNSS signals in urban canyons. GNSS signals may reach a receiver not only through Line-of-Sight (LOS paths, but they are often blocked, reflected or diffracted from tall buildings, leading to unmodelled GNSS errors in position estimation. Therefore in order to detect and mitigate the impact of multipath, a new ray-tracing model for simulation of GNSS signals reception in urban canyons is proposed - based on digital 3D maps information, known positions of GNSS satellites and an assumed position of a receiver. The model is established and validated using experimental, as well as real data. It is specially designed for complex environments and situations where positioning with highest accuracy is required - a typical example is navigation for blind people.

  15. GNSS Precise Kinematic Positioning for Multiple Kinematic Stations Based on A Priori Distance Constraints.

    Science.gov (United States)

    He, Kaifei; Xu, Tianhe; Förste, Christoph; Petrovic, Svetozar; Barthelmes, Franz; Jiang, Nan; Flechtner, Frank

    2016-04-01

    When applying the Global Navigation Satellite System (GNSS) for precise kinematic positioning in airborne and shipborne gravimetry, multiple GNSS receiving equipment is often fixed mounted on the kinematic platform carrying the gravimetry instrumentation. Thus, the distances among these GNSS antennas are known and invariant. This information can be used to improve the accuracy and reliability of the state estimates. For this purpose, the known distances between the antennas are applied as a priori constraints within the state parameters adjustment. These constraints are introduced in such a way that their accuracy is taken into account. To test this approach, GNSS data of a Baltic Sea shipborne gravimetric campaign have been used. The results of our study show that an application of distance constraints improves the accuracy of the GNSS kinematic positioning, for example, by about 4 mm for the radial component.

  16. Approximation properties of haplotype tagging

    Directory of Open Access Journals (Sweden)

    Dreiseitl Stephan

    2006-01-01

    Full Text Available Abstract Background Single nucleotide polymorphisms (SNPs are locations at which the genomic sequences of population members differ. Since these differences are known to follow patterns, disease association studies are facilitated by identifying SNPs that allow the unique identification of such patterns. This process, known as haplotype tagging, is formulated as a combinatorial optimization problem and analyzed in terms of complexity and approximation properties. Results It is shown that the tagging problem is NP-hard but approximable within 1 + ln((n2 - n/2 for n haplotypes but not approximable within (1 - ε ln(n/2 for any ε > 0 unless NP ⊂ DTIME(nlog log n. A simple, very easily implementable algorithm that exhibits the above upper bound on solution quality is presented. This algorithm has running time O((2m - p + 1 ≤ O(m(n2 - n/2 where p ≤ min(n, m for n haplotypes of size m. As we show that the approximation bound is asymptotically tight, the algorithm presented is optimal with respect to this asymptotic bound. Conclusion The haplotype tagging problem is hard, but approachable with a fast, practical, and surprisingly simple algorithm that cannot be significantly improved upon on a single processor machine. Hence, significant improvement in computatational efforts expended can only be expected if the computational effort is distributed and done in parallel.

  17. Predicting floods with Flickr tags.

    Science.gov (United States)

    Tkachenko, Nataliya; Jarvis, Stephen; Procter, Rob

    2017-01-01

    Increasingly, user generated content (UGC) in social media postings and their associated metadata such as time and location stamps are being used to provide useful operational information during natural hazard events such as hurricanes, storms and floods. The main advantage of these new sources of data are twofold. First, in a purely additive sense, they can provide much denser geographical coverage of the hazard as compared to traditional sensor networks. Second, they provide what physical sensors are not able to do: By documenting personal observations and experiences, they directly record the impact of a hazard on the human environment. For this reason interpretation of the content (e.g., hashtags, images, text, emojis, etc) and metadata (e.g., keywords, tags, geolocation) have been a focus of much research into social media analytics. However, as choices of semantic tags in the current methods are usually reduced to the exact name or type of the event (e.g., hashtags '#Sandy' or '#flooding'), the main limitation of such approaches remains their mere nowcasting capacity. In this study we make use of polysemous tags of images posted during several recent flood events and demonstrate how such volunteered geographic data can be used to provide early warning of an event before its outbreak.

  18. b-tagging in DELPHI at LEP

    CERN Document Server

    Abdallah, J; Adam, W; Adye, T; Adzic, P; Albrecht, T; Alderweireld, T; Alemany-Fernandez, R; Allmendinger, T; Allport, P P; Almehed, S; Amaldi, Ugo; Amapane, N; Amato, S; Anashkin, E; Andreazza, A; Andringa, S; Anjos, N; Antilogus, P; Apel, W D; Arnoud, Y; Ask, S; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Ballestrero, A; Bambade, P; Barbier, R; Bardin, Dimitri Yuri; Barker, G; Baroncelli, A; Bates, M; Battaglia, Marco; Baubillier, M; Becks, K H; Begalli, M; Behrmann, A; Benekos, N C; Benvenuti, Alberto C; Bérat, C; Berggren, M; Berntzon, L; Bertrand, D; Besançon, M; Besson, N; Bibby, J; Biffi, P; Bloch, D; Blom, M; Bonesini, M; Boonekamp, M; Booth, P S L; Borisov, G; Botner, O; Bouquet, B; Bowcock, T J V; Boyko, I; Bracko, M; Branchini, P; Brenner, R; Brodet, E; Brückman, P; Brunet, J M; Bugge, L; Buschmann, P; Caccia, M; Calvi, M; Camporesi, T; Canale, V; Carena, F; Castro, N; Cavallo, F R; Chabaud, V; Chapkin, M M; Charpentier, P; Checchia, P; Chierici, R; Shlyapnikov, P; Chudoba, J; Chung, S U; Cieslik, K; Collins, P; Contri, R; Cosme, G; Cossutti, F; Costa, M J; Couchot, F; Crawley, B; Crennell, D J; Cuevas-Maestro, J; D'Almagne, B; D'Hondt, J; Dalmau, J; Da Silva, T; Da Silva, W; Della Ricca, G; De Angelis, A; de Boer, Wim; De Clercq, C; De Lotto, B; De Maria, N; De Min, A; De Paula, L S; Di Ciaccio, Lucia; Dijkstra, H; Di Simone, A; Doroba, K; Drees, J; Dris, M; Eigen, G; Ekelöf, T J C; Ellert, M; Elsing, M; Espirito-Santo, M C; Fanourakis, G K; Fassouliotis, D; Feindt, M; Fernández, J; Ferrer, A; Ferro, F; Flagmeyer, U; Föth, H; Fokitis, E; Fulda-Quenzer, F; Fuster, J A; Gandelman, M; García, C; Gavillet, P; Gazis, E N; Geralis, T; Gokieli, R; Golob, B; Gómez-Cadenas, J J; Gómez-Ceballos, G; Gonçalves, P; Graziani, E; Grosdidier, G; Grzelak, K; Guy, J; Haag, C; Hallgren, A; Hamacher, K; Hamilton, K; Hansen, J; Haug, S; Hauler, F; Hedberg, V; Hennecke, M; Hernando, J A; Herr, H; Heuser, J M; Holmgren, S O; Holt, P J; Houlden, M A; Hultqvist, K; Jackson, J N; Jalocha, P; Jarlskog, C; Jarlskog, G; Jarry, P; Jeans, D; Johansson, E K; Johansson, P D; Jonsson, P; Joram, C; Jungermann, L; Kapusta, F; Karlsson, M; Katsanevas, S; Katsoufis, E C; Keränen, R; Kernel, G; Kersevan, Borut P; Kiiskinen, A P; King, B T; Kjaer, N J; Kluit, P; Kokkinias, P; Kourkoumelis, C; Kuznetsov, O; Krumshtein, Z; Kucharczyk, M; Kucewicz, W; Kurowska, J; Lamsa, J; Leder, G; Ledroit, F; Leinonen, L; Leitner, R; Lemonne, J; Lepeltier, V; Lesiak, T; Liebig, W; Liko, D; Lipniacka, A; Lopes, J H; López, J M; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J; Malek, A; Maltezos, S; Mandl, F; Marco, J; Marco, R; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Martínez-Vidal, F; Masik, J; Mastroyiannopoulos, N; Matorras, F; Matteuzzi, C; Mazzucato, F; Mazzucato, M; McNulty, R; Meroni, C; Meyer, W T; Migliore, E; Mitaroff, W A; Mjörnmark, U; Moa, T; Moch, M; Mönig, K; Monge, R; Montenegro, J; Moraes, D; Moreno, S; Morettini, P; Müller, U; Münich, K; Mulders, M; Mundim, L; Murray, W; Muryn, B; Myatt, Gerald; Myklebust, T; Nassiakou, M; Navarria, Francesco Luigi; Nawrocki, K; Nicolaidou, R; Niezurawski, P; Nikolenko, M; Nomerotski, A; Norman, A; Nygren, A; Oblakowska-Mucha, A; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Österberg, K; Ouraou, A; Oyanguren, A; Paganoni, M; Paiano, S; Palacios, J P; Palka, H; Papadopoulou, T D; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Passon, O; Peralta, L; Perepelitsa, V F; Perrotta, A; Petrolini, A; Piedra, J; Pieri, L; Pierre, F; Pimenta, M; Piotto, E; Podobnik, T; Poireau, V; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Pukhaeva, N; Pullia, Antonio; Rames, J; Ramler, L; Read, A; Rebecchi, P; Rehn, J; Reid, D; Reinhardt, R; Renton, P B; Richard, F; Rídky, J; Rivero, M; Rodríguez, D; Romero, A; Ronchese, P; Rosenberg, E I; Roudeau, Patrick; Rovelli, T; Ruhlmann-Kleider, V; Ryabtchikov, D; Sadovskii, A; Salmi, L; Salt, J; Savoy-Navarro, A; Schwickerath, U; Segar, A; Sekulin, R L; Siebel, M; Sissakian, A N; Smadja, G; Smirnova, O G; Sokolov, A; Sopczak, A; Sosnowski, R; Spassoff, Tz; Stanitzki, M; Stavitski, I; Stocchi, A; Strauss, J; Stugu, B; Szczekowski, M; Szeptycka, M; Szumlak, T; Tabarelli de Fatis, T; Taffard, A C; Tegenfeldt, F; Timmermans, J; Tinti, N; Tkatchev, L G; Tobin, M; Todorovova, S; Tomaradze, A G; Tomé, B; Tonazzo, A; Tortosa, P; Travnicek, P; Treille, D; Trischuk, W; Tristram, G; Trochimczuk, M; Troncon, C; Turluer, M L; Tyapkin, I A; Tyapkin, P; Tyndel, M; Tzamarias, S; Uvarov, V; Valenti, G; van Dam, P; Van Eldik, J; Van Lysebetten, A; Van Remortel, N; Van Vulpen, I B; Vegni, G; Veloso, F; Venus, W A; Verbeure, F; Verdier, P; Verzi, V; Vilanova, D; Vitale, L; Vrba, V; Wahlen, H; Washbrook, A J; Weilhammer, Peter; Weiser, C; Wicke, D; Wickens, J H; Wilkinson, G; Winter, M; Witek, M; Yushchenko, O P; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zimin, N I; Zinchenko, A I; Zupan, M

    2004-01-01

    The standard method used for tagging b-hadrons in the DELPHI experiment at the CERN LEP Collider is discussed in detail. The main ingredient of b-tagging is the impact parameters of tracks, which relies mostly on the vertex detector. Additional information, such as the mass of particles associated to a secondary vertex, significantly improves the selection efficiency and the background suppression. The paper describes various discriminating variables used for the tagging and the procedure of their combination. In addition, applications of b-tagging to some physics analyses, which depend crucially on the performance and reliability of b-tagging, are described briefly.

  19. Mapping sea ice using reflected GNSS signals in a bistatic radar system

    Science.gov (United States)

    Chew, Clara; Zuffada, Cinzia; Shah, Rashmi; Mannucci, Anthony

    2016-04-01

    Global Navigation Satellite System (GNSS) signals can be used as a kind of bistatic radar, with receivers opportunistically recording ground-reflected signals transmitted by the GNSS satellites themselves. This technique, GNSS-Reflectometry (GNSS-R), has primarily been explored using receivers flown on aircraft or balloons, or in modeling studies. Last year's launch of the TechDemoSat-1 (TDS-1) satellite represents an enormous opportunity to investigate the potential of using spaceborne GNSS receivers to sense changes in the land and ocean surface. Here, we examine the ability of reflected GNSS signals to estimate sea ice extent and sea ice age, as well as comment on the possibility of using GNSS-R to detect leads and polynyas within the ice. In particular, we quantify how the peak power of Delay Doppler Maps (DDMs) generated within the GNSS receiver responds as the satellite flies over the Polar Regions. To compute the effective peak power of each DDM, we first normalize the peak power of the DDM by the noise floor. We also correct for antenna gain, range, and incidence angle. Once these corrections are made, the effective peak power across DDMs may be used as a proxy for changes in surface permittivity and surface roughness. We compare our calculations of reflected power to existing sea ice remote sensing products such as data from the SSMI/S as well as Landsat imagery. Our analysis shows that GNSS reflections are extremely sensitive to the sea ice edge, with increases in reflected power of more than 10 dB relative to reflected power over the open ocean. As the sea ice ages, it thickens and roughens, and reflected power decreases, though it does not decrease below the power over the open ocean. Given the observed sensitivity of GNSS reflections to small features over land and the sensitivity to the sea ice edge, we hypothesize that reflection data could help map the temporal evolution of leads and polynyas.

  20. Secure passive RFID tag with seal

    Energy Technology Data Exchange (ETDEWEB)

    Nekoogar, Faranak; Reynolds, Matthew; Lefton, Scott; Dowla, Farid; Twogood, Richard

    2017-11-14

    A secure passive RFID tag system comprises at least one base station and at least one passive RFID tag. The tag includes a fiber optic cable with the cable ends sealed within the tag and the middle portion forming an external loop. The loop may be secured to at least portions of an object. The tag transmits and receives an optical signal through the fiber optic cable, and the cable is configured to be damaged or broken in response to removal or tampering attempts, wherein the optical signal is significantly altered if the cable is damaged or broken. The tag transmits the optical signal in response to receiving a radio signal from the base station and compares the transmitted optical signal to the received optical signal. If the transmitted optical signal and the received optical signal are identical, the tag transmits an affirmative radio signal to the base station.

  1. Acceleration induced water removal from ear canals.

    Science.gov (United States)

    Kang, Hosung; Averett, Katelee; Jung, Sunghwan

    2017-11-01

    Children and adults commonly experience having water trapped in the ear canals after swimming. To remove the water, individuals will shake their head sideways. Since a child's ear canal has a smaller diameter, it requires more acceleration of the head to remove the trapped water. In this study, we theoretically and experimentally investigated the acceleration required to break the surface meniscus of the water in artificial ear canals and hydrophobic-coated glass tubes. In experiments, ear canal models were 3D-printed from a CT-scanned human head. Also, glass tubes were coated with silane to match the hydrophobicity in ear canals. Then, using a linear stage, we measured the acceleration values required to forcefully eject the water from the artificial ear canals and glass tubes. A theoretical model was developed to predict the critical acceleration at a given tube diameter and water volume by using a modified Rayleigh-Taylor instability. Furthermore, this research can shed light on the potential of long-term brain injury and damage by shaking the head to push the water out of the ear canal. This research was supported by National Science Foundation Grant CBET-1604424.

  2. Predictions of middle-ear and passive cochlear mechanics using a finite element model of the pediatric ear

    OpenAIRE

    Wang, Xuelin; Keefe, Douglas H.; Gan, Rong Z.

    2016-01-01

    A finite element (FE) model was developed based on histological sections of a temporal bone of a 4-year-old child to simulate middle-ear and cochlear function in ears with normal hearing and otitis media. This pediatric model of the normal ear, consisting of an ear canal, middle ear, and spiral cochlea, was first validated with published energy absorbance (EA) measurements in young children with normal ears. The model was used to simulate EA in an ear with middle-ear effusion, whose results w...

  3. Kilometer-Spaced GNSS Array for Ionospheric Irregularity Monitoring

    Science.gov (United States)

    Su, Yang

    This dissertation presents automated, systematic data collection, processing, and analysis methods for studying the spatial-temporal properties of Global Navigation Satellite Systems (GNSS) scintillations produced by ionospheric irregularities at high latitudes using a closely spaced multi-receiver array deployed in the northern auroral zone. The main contributions include 1) automated scintillation monitoring, 2) estimation of drift and anisotropy of the irregularities, 3) error analysis of the drift estimates, and 4) multi-instrument study of the ionosphere. A radio wave propagating through the ionosphere, consisting of ionized plasma, may suffer from rapid signal amplitude and/or phase fluctuations known as scintillation. Caused by non-uniform structures in the ionosphere, intense scintillation can lead to GNSS navigation and high-frequency (HF) communication failures. With specialized GNSS receivers, scintillation can be studied to better understand the structure and dynamics of the ionospheric irregularities, which can be parameterized by altitude, drift motion, anisotropy of the shape, horizontal spatial extent and their time evolution. To study the structuring and motion of ionospheric irregularities at the sub-kilometer scale sizes that produce L-band scintillations, a closely-spaced GNSS array has been established in the auroral zone at Poker Flat Research Range, Alaska to investigate high latitude scintillation and irregularities. Routinely collecting low-rate scintillation statistics, the array database also provides 100 Hz power and phase data for each channel at L1/L2C frequency. In this work, a survey of seasonal and hourly dependence of L1 scintillation events over the course of a year is discussed. To efficiently and systematically study scintillation events, an automated low-rate scintillation detection routine is established and performed for each day by screening the phase scintillation index. The spaced-receiver technique is applied to cross

  4. Development of real-time GNSS ZTD products

    Science.gov (United States)

    Dousa, Jan; Vaclavovic, Pavel; Gyori, Gabriel; Kostelecky, Jan

    2013-04-01

    Geodetic Observatory Pecný (GOP) has been routinely estimating near real-time zenith total delay (ZTD) parameters from GPS permanent stations since 2001. Currently, the GOP ZTDs are assimilated in several meteorological institutions. During last years new other tropospheric products were developed at GOP: 1) global hourly ZTD product, 2) multi-GNSS (GPS+GLONASS) regional ZTD product and 3) real-time ZTD product. All operationally running hourly updated ZTD solutions (stand-alone GPS, multi-GNSS and global) are based on the processing of batch data in a differential mode and using Bernese GNSS software and IGS ultra-rapid orbits. New real-time ZTD solution is implemented with completely different strategy - the Precise Point Positioning (PPP) and filtering technique - using real-time data streams and products and applying new developed software in GOP. Firstly, the presentation gives a brief introduction into the in-house software library (G-Nut) development and into the specific end-user application Tefnut, which was implemented for PPP-based tropospheric estimates in post-processing, near real-time and real-time modes. Tefnut is ready for its first release, which will be available through www.pecny.cz. Secondly, ZTDs based on new software and strategy were evaluated with respect to the precise products from EUREF and IGS using a benchmark campaing over 40 days. Statistical evaluation included both post-processing and real-time (simulated) mode. Finally, an operational real-time performance of new product is demonstrated, which is aimed for the now-casting and severe weather monitoring applications. Statistical ZTD results (standard deviations of 5-8 mm) proved that PPP using IGS real-time orbit and clock products are already well suitable to fulfill the requirements of now-casting applications. Ongoing work is assessing an optimal balance between the timelines and the product quality.

  5. Emergency response to landslide using GNSS measurements and UAV

    Science.gov (United States)

    Nikolakopoulos, Konstantinos G.; Koukouvelas, Ioannis K.

    2017-10-01

    Landslide monitoring can be performed using many different methods: Classical geotechnical measurements like inclinometer, topographical survey measurements with total stations or GNSS sensors and photogrammetric techniques using airphotos or high resolution satellite images. However all these methods are expensive or difficult to be developed immediately after the landslide triggering. In contrast airborne technology and especially the use of Unmanned Aerial Vehicles (UAVs) make response to landslide disaster easier as UAVs can be launched quickly in dangerous terrains and send data about the sliding areas to responders on the ground either as RGB images or as videos. In addition, the emergency response to landslide is critical for the further monitoring. For proper displacement identification all the above mentioned monitoring methods need a high resolution and a very accurate representation of the relief. The ideal solution for the accurate and quick mapping of a landslide is the combined use of UAV's photogrammetry and GNSS measurements. UAVs have started their development as expensive toys but they currently became a very valuable tool in large scale mapping of sliding areas. The purpose of this work is to demonstrate an effective solution for the initial landslide mapping immediately after the occurrence of the phenomenon and the possibility of the periodical assessment of the landslide. Three different landslide cases from Greece are presented in the current study. All three landslides have different characteristics: occurred in different geomorphologic environments, triggered by different causes and had different geologic bedrock. In all three cases we performed detailed GNSS measurements of the landslide area, we generated orthophotos as well as Digital Surface Models (DSMs) at an accuracy of less than +/-10 cm. Slide direction and velocity, mass balances as well as protection and mitigation measurements can be derived from the application of the UAVs

  6. GNSS Spoofing Network Monitoring Based on Differential Pseudorange.

    Science.gov (United States)

    Zhang, Zhenjun; Zhan, Xingqun

    2016-10-23

    Spoofing is becoming a serious threat to various Global Navigation Satellite System (GNSS) applications, especially for those that require high reliability and security such as power grid synchronization and applications related to first responders and aviation safety. Most current works on anti-spoofing focus on spoofing detection from the individual receiver side, which identifies spoofing when it is under an attack. This paper proposes a novel spoofing network monitoring (SNM) mechanism aiming to reveal the presence of spoofing within an area. Consisting of several receivers and one central processing component, it keeps detecting spoofing even when the network is not attacked. The mechanism is based on the different time difference of arrival (TDOA) properties between spoofing and authentic signals. Normally, TDOAs of spoofing signals from a common spoofer are identical while those of authentic signals from diverse directions are dispersed. The TDOA is measured as the differential pseudorange to carrier frequency ratio (DPF). In a spoofing case, the DPFs include those of both authentic and spoofing signals, among which the DPFs of authentic are dispersed while those of spoofing are almost overlapped. An algorithm is proposed to search for the DPFs that are within a pre-defined small range, and an alarm will be raised if several DPFs are found within such range. The proposed SNM methodology is validated by simulations and a partial field trial. Results show 99.99% detection and 0.01% false alarm probabilities are achieved. The SNM has the potential to be adopted in various applications such as (1) alerting dedicated users when spoofing is occurring, which could significantly shorten the receiver side spoofing cost; (2) in combination with GNSS performance monitoring systems, such as the Continuous Operating Reference System (CORS) and GNSS Availability, Accuracy, Reliability anD Integrity Assessment for Timing and Navigation (GAARDIAN) System, to provide more

  7. Imaging of the postoperative middle ear

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Marc T. [Department of Medical Imaging, Fondation Ophtalmologique Adolphe de Rothschild, 25 rue Manin, 75940, Paris (France); Ayache, Denis [Department of Otorhinolaryngology, Fondation Ophtalmologique Adolphe de Rothschild, Paris (France)

    2004-03-01

    The aim of this article is twofold: (a) to present the principles and the indications of surgical treatment of middle ear pathologies; and (b) to review the imaging findings after middle ear surgery, including the normal postoperative aspects and imaging findings in patients presenting with unsatisfactory surgical results or with suspicion of postoperative complications. This review is intentionally restricted to the most common diseases involving the middle ear: chronic otitis media and otosclerosis. In these specific fields of interest, CT and MR imaging play a very important role in the postoperative follow-up and in the work-up of surgical failures and complications. (orig.)

  8. Coupled ears in lizards and crocodilians

    DEFF Research Database (Denmark)

    Carr, Catherine E; Christensen-Dalsgaard, Jakob; Bierman, Hilary

    2016-01-01

    Lizard ears are coupled across the pharynx, and are very directional. In consequence all auditory responses should be directional, without a requirement for computation of sound source location. Crocodilian ears are connected through sinuses, and thus less tightly coupled. Coupling may improve...... the processing of low-frequency directional signals, while higher frequency signals appear to be progressively uncoupled. In both lizards and crocodilians, the increased directionality of the coupled ears leads to an effectively larger head and larger physiological range of ITDs. This increased physiological...

  9. Tsunami Amplitude Estimation from Real-Time GNSS.

    Science.gov (United States)

    Jeffries, C.; MacInnes, B. T.; Melbourne, T. I.

    2017-12-01

    Tsunami early warning systems currently comprise modeling of observations from the global seismic network, deep-ocean DART buoys, and a global distribution of tide gauges. While these tools work well for tsunamis traveling teleseismic distances, saturation of seismic magnitude estimation in the near field can result in significant underestimation of tsunami excitation for local warning. Moreover, DART buoy and tide gauge observations cannot be used to rectify the underestimation in the available time, typically 10-20 minutes, before local runup occurs. Real-time GNSS measurements of coseismic offsets may be used to estimate finite faulting within 1-2 minutes and, in turn, tsunami excitation for local warning purposes. We describe here a tsunami amplitude estimation algorithm; implemented for the Cascadia subduction zone, that uses continuous GNSS position streams to estimate finite faulting. The system is based on a time-domain convolution of fault slip that uses a pre-computed catalog of hydrodynamic Green's functions generated with the GeoClaw shallow-water wave simulation software and maps seismic slip along each section of the fault to points located off the Cascadia coast in 20m of water depth and relies on the principle of the linearity in tsunami wave propagation. The system draws continuous slip estimates from a message broker, convolves the slip with appropriate Green's functions which are then superimposed to produce wave amplitude at each coastal location. The maximum amplitude and its arrival time are then passed into a database for subsequent monitoring and display. We plan on testing this system using a suite of synthetic earthquakes calculated for Cascadia whose ground motions are simulated at 500 existing Cascadia GPS sites, as well as real earthquakes for which we have continuous GNSS time series and surveyed runup heights, including Maule, Chile 2010 and Tohoku, Japan 2011. This system has been implemented in the CWU Geodesy Lab for the Cascadia

  10. Real-time GNSS volcano deformation monitoring (Invited)

    Science.gov (United States)

    Lisowski, M.; Langbein, J. O.; Hudnut, K. W.

    2013-12-01

    We present comparisons of the precision obtained from several alternative real-time GNSS processing methods, and show how offsets caused by snow and ice on an antenna can be automatically identified in real time using signal-to-noise ratio (SNR) data. We monitor ground deformation using continuous GNSS stations installed on several volcanoes in the Cascade Range and elsewhere, and many of these stations transmit high-rate (1s) data in real-time. We examine real-time, high-rate station position solutions obtained with two implementations of centralized RTNet (GPS Solutions, Inc.) processing, and find that the precision is roughly the same for ambiguity-fixed network solutions and for ambiguity-fixed precise point position solutions (PPPAR). The PPPAR method uses satellite clock corrections provided by GPS Solutions from a network of Plate Boundary Observatory (PBO) stations in western Oregon. The precision of network solutions that include GPS and GLONASS data is similar to the GPS-only solutions, except at stations with a relatively poor view of the sky. An alternative method of processing the real-time GPS data uses clock corrections transmitted directly to the receiver, which then autonomously calculates and transmits positions. We will compare our RTNet results with autonomous point position solutions calculated using Trimble's CenterPoint RTX corrections. RTX performance in repeated, controlled, large antenna-motion tests by USGS and UNAVCO indicates that it meets requirements of USGS volcano-monitoring applications; more thorough testing and performance checks on an ongoing basis would be desirable. GNSS antennas on volcanoes often become temporarily coated with ice or buried by snow in the winter. In these situations, signal delays introduce an apparent offset in the monitoring station's position. We address this problem by implementing in real time a technique developed by Kristine Larson that uses changes in the signal-to-noise ratio (SNR) of GNSS signals

  11. Real-time data flow and product generating for GNSS

    Science.gov (United States)

    Muellerschoen, Ronald J.; Caissy, Mark

    2004-01-01

    The last IGS workshop with the theme 'Towards Real-Time' resulted in the design of a prototype for real-time data and sharing within the IGS. A prototype real-time network is being established that will serve as a test bed for real-time activities within the IGS. We review the developments of the prototype and discuss some of the existing methods and related products of real-time GNSS systems. Recommendations are made concerning real-time data distribution and product generation.

  12. A Novel Residual Frequency Estimation Method for GNSS Receivers.

    Science.gov (United States)

    Nguyen, Tu Thi-Thanh; La, Vinh The; Ta, Tung Hai

    2018-01-04

    In Global Navigation Satellite System (GNSS) receivers, residual frequency estimation methods are traditionally applied in the synchronization block to reduce the transient time from acquisition to tracking, or they are used within the frequency estimator to improve its accuracy in open-loop architectures. There are several disadvantages in the current estimation methods, including sensitivity to noise and wide search space size. This paper proposes a new residual frequency estimation method depending on differential processing. Although the complexity of the proposed method is higher than the one of traditional methods, it can lead to more accurate estimates, without increasing the size of the search space.

  13. Quality assessment of multi-GNSS real-time orbits and clocks

    Science.gov (United States)

    Kaźmierski, Kamil; Sośnica, Krzysztof; Hadaś, Tomasz

    2017-04-01

    A continuously increasing number of satellites of Global Navigation Satellites Systems (GNSS) and their constant modernization allow improving the positioning accuracy and enables performing the GNSS measurements in challenging environments. The constant development of GNSS, among which GPS, GLONASS, Galileo and BeiDou can be distinguished, contributes to improvements in GNSS usage in areas desired by common users or GNSS community. The Multi-GNSS experiment (MGEX) of the International GNSS Service (IGS) has been established for tracking, collating and analyzing all available GNSS signals. Provided precise orbits and clocks do not allow users to process data in real-time due to the significant latency of provided products which may reach up to even 18 days. In order to satisfy needs of real-time users IGS Real-Time Service (RTS) was launched in 2013. The service is currently insufficient for Multi-GNSS applications as it provides products for GPS and GLONASS only. One of the publicly available real-time corrections for the all GNSS, including the new systems, are those provided by the Centre National d'etudes Spatiales (CNES). Presented works evaluate clocks and orbit corrections, i.e., the availability and quality of real-time products provided by CNES (mountpoint CLK93). As a decoder of the RTCM streams the BNC software v2.12 is used. All computations are performed using the GNSS-WARP software which is developed by Institute of Geodesy and Geoinformatics (IGG) at Wroclaw University of Environmental and Life Sciences (WUELS). The final products provided by the Center of Orbit Determination in Europe (CODE) are used for the evaluation of the real-time CNES orbits and clocks. Moreover, the Satellite Laser Ranging (SLR) data are employed as an independent way of the orbit quality assessment. The availability of the real-time corrections is at the level of about 90%, when excluding BeiDou, for which the availability is at the level of about 80%. The obtained results

  14. Structural Metadata Research in the Ears Program

    National Research Council Canada - National Science Library

    Liu, Yang; Shriberg, Elizabeth; Stolcke, Andreas; Peskin, Barbara; Ang, Jeremy; Hillard, Dustin; Ostendorf, Mari; Tomalin, Marcus; Woodland, Phil; Harper, Mary

    2005-01-01

    Both human and automatic processing of speech require recognition of more than just words. In this paper we provide a brief overview of research on structural metadata extraction in the DARPA EARS rich transcription program...

  15. Diode Laser Ear Piercing: A Novel Technique.

    Science.gov (United States)

    Suseela, Bibilash Babu; Babu, Preethitha; Chittoria, Ravi Kumar; Mohapatra, Devi Prasad

    2016-01-01

    Earlobe piercing is a common office room procedure done by a plastic surgeon. Various methods of ear piercing have been described. In this article, we describe a novel method of laser ear piercing using the diode laser. An 18-year-old female patient underwent an ear piercing using a diode laser with a power of 2.0 W in continuous mode after topical local anaesthetic and pre-cooling. The diode laser was fast, safe, easy to use and highly effective way of ear piercing. The advantages we noticed while using the diode laser over conventional methods were more precision, minimal trauma with less chances of hypertrophy and keloids, no bleeding with coagulation effect of laser, less time taken compared to conventional method and less chance of infection due to thermal heat effect of laser.

  16. Animal Models of Middle Ear Cholesteatoma

    Directory of Open Access Journals (Sweden)

    Tomomi Yamamoto-Fukuda

    2011-01-01

    Full Text Available Middle ear acquired cholesteatoma is a pathological condition associated with otitis media, which may be associated with temporal bone resorption, otorrhea and hearing loss, and occasionally various other complications. Cholesteatoma is characterized by the enhanced proliferation of epithelial cells with aberrant morphologic characteristics. Unfortunately, our understanding of the mechanism underlying its pathogenesis is limited. To investigate its pathogenesis, different animal models have been used. This paper provides a brief overview of the current status of research in the field of pathogenesis of middle ear acquired cholesteatoma, four types of animal models previously reported on, up-to-date cholesteatoma research using these animal models, our current studies of the local hybrid ear model, and the future prospect of new animal models of middle ear cholesteatoma.

  17. Environment for Auditory Research Facility (EAR)

    Data.gov (United States)

    Federal Laboratory Consortium — EAR is an auditory perception and communication research center enabling state-of-the-art simulation of various indoor and outdoor acoustic environments. The heart...

  18. Ear Infection Treatment: Do Alternative Therapies Work?

    Science.gov (United States)

    ... in books and magazines. They include chiropractic adjustments, homeopathy, herbal eardrops and others. Perhaps you're seeking ... infection treatments have been studied with mixed results. Homeopathy. A controversial treatment for ear infection, homeopathy involves ...

  19. Mozart ear: diagnosis, treatment, and literature review.

    Science.gov (United States)

    Yamashita, Ken; Yotsuyanagi, Takatoshi; Saito, Tamotsu; Isogai, Noritaka; Mori, Hiromasa; Itani, Yoshihito

    2011-11-01

    Mozart ear is a congenital auricular deformity, which is mainly characterized by a bulging appearance of the anterosuperior portion of the auricle, a convexly protruded cavum conchae, and a slit-like narrowing of the orifice of the external auditory meatus. It is said to be uncommon, and because no one has yet fully described neither the disease nor the treatment, the concept of Mozart ear has not been unified. This report describes a case of a 13-year-old girl presented with an unusual congenital deformity which showed the features of Mozart ear. It is an extremely rare deformity that only about 4 clinical cases have been reported in medical literature thereby a treatment method has not been fully discussed. For surgical correction of our cases, we excised deformed conchal cartilage, turned it over, regrafted, and maintained a cosmetically positive result. We also reviewed and described the origin, current concept, and treatment method of Mozart ear.

  20. Development of a GNSS Buoy for Monitoring Water Surface Elevations in Estuaries and Coastal Areas.

    Science.gov (United States)

    Lin, Yen-Pin; Huang, Ching-Jer; Chen, Sheng-Hsueh; Doong, Dong-Jiing; Kao, Chia Chuen

    2017-01-18

    In this work, a Global Navigation Satellite System (GNSS) buoy that utilizes a Virtual Base Station (VBS) combined with the Real-Time Kinematic (RTK) positioning technology was developed to monitor water surface elevations in estuaries and coastal areas. The GNSS buoy includes a buoy hull, a RTK GNSS receiver, data-transmission devices, a data logger, and General Purpose Radio Service (GPRS) modems for transmitting data to the desired land locations. Laboratory and field tests were conducted to test the capability of the buoy and verify the accuracy of the monitored water surface elevations. For the field tests, the GNSS buoy was deployed in the waters of Suao (northeastern part of Taiwan). Tide data obtained from the GNSS buoy were consistent with those obtained from the neighboring tide station. Significant wave heights, zero-crossing periods, and peak wave directions obtained from the GNSS buoy were generally consistent with those obtained from an accelerometer-tilt-compass (ATC) sensor. The field tests demonstrate that the developed GNSS buoy can be used to obtain accurate real-time tide and wave data in estuaries and coastal areas.

  1. GNSS-based train positioning experiments with local and wide area augmentation

    Energy Technology Data Exchange (ETDEWEB)

    Gu, X.; Schmidt, M.; Winter, J. [DaimlerChrysler Rail Systems (Signals) GmbH, Ulm (Germany)

    1999-07-01

    Within the frame of the MAGNET Project ('Multimodal Approach for GNSS 1 in European Transport') of the Telematics Applications programme of the 4{sup th} Research Framework of the European Community (1994-1998), a GNSS-based Train Positioning Platform (TPP) has been developed and tested with the wide area augmentation system pre-EGNOS and a local differential GNSS system using a reference station. This paper presents the principle and the system architecture of the developed GNSS-based train positioning system and highlights the system performance achieved in field tests. The TPP consists of a GNSS core module with an EGNOS (European Geostationary Navigation Overlay Service) decoding function, a GSM (Global System for Mobile Communication) data link for local GPS and GLONASS differential corrections, a digital route map and an interface to odometer. The first step to calculate the train position is to select either wide area or local area differential corrections depending on which are available. The position and velocity are then calculated and matched to the track by using the digital route map. Finally, the GNSS position and velocity data is integrated with odometer data in a sensor data fusion model. The integrated solution avoids the masking problem of GNSS signals and reduces odometer errors like drift and braking slip, so that a continuous positioning availability can be reached and the positioning accuracy can be improved to meter level. The achieved performance is being exploited for industrial applications. (orig.)

  2. Influence of Ear Surface Area on Heat Tolerance of Composite ...

    African Journals Online (AJOL)

    Low correlation (r = 0.12) was observed between body weight and ear width. There were no correlations between ear width, respiratory rates and pulse rate. However, a residual correlation (r = -0.03) was obtained between ear width and body temperature. Large ear surface area in composite rabbits enhances better ...

  3. Osteoma of the middle ear: case report

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Ji Hwa [College of Medicine, Inje University, Dongrae Paik Hospital, Busan (Korea, Republic of)

    2005-07-15

    Osteomas of the middle ear are exceedingly rare benign neoplasms. To date, only 21 cases have been reported in the literature. They arise from the promontory, the pyramidal process and the ossicles, and they are usually asymptomatic or cause some conductive hearing loss. We report here the CT and pathologic findings in a 38-year-old woman with a benign osteoma of the middle ear along with chronic otitis media.

  4. Commissioning of n_TOF EAR2

    CERN Multimedia

    The construction of the second beam line and experiment area (EAR2) of the n_TOF facility is currently ongoing and scheduled to be completed by July 2014. An extensive series of measurements is planned in order to determine the beam characteristics like the neutron flux, the spatial beam profile and the resolution function, as well as the response of several detectors considered for use in future measurements at EAR2. A rigorous study of backgrounds will be undertaken in various conditions.

  5. Operational space weather service for GNSS precise positioning

    Directory of Open Access Journals (Sweden)

    N. Jakowski

    2005-11-01

    Full Text Available The ionospheric plasma can significantly influence the propagation of radio waves and the ionospheric disturbances are capable of causing range errors, rapid phase and amplitude fluctuations (radio scintillations of satellite signals that may lead to degradation of the system performance, its accuracy and reliability. The cause of such disturbances should be sought in the processes originating in the Sun. Numerous studies on these phenomena have been already carried out at a broad international level, in order to measure/estimate these space weather induced effects, to forecast them, and to understand and mitigate their impact on present-day technological systems.

    SWIPPA (Space Weather Impact on Precise Positioning Applications is a pilot project jointly supported by the German Aerospace Centre (DLR and the European Space Agency (ESA. The project aims at establishing, operating, and evaluating a specific space-weather monitoring service that can possibly lead to improving current positioning applications based on Global Navigation Satellite Systems (GNSS. This space weather service provides GNSS users with essential expert information delivered in the form of several products - maps of TEC values, TEC spatial and temporal gradients, alerts for ongoing/oncoming ionosphere disturbances, etc.

  6. Operational space weather service for GNSS precise positioning

    Directory of Open Access Journals (Sweden)

    N. Jakowski

    2005-11-01

    Full Text Available The ionospheric plasma can significantly influence the propagation of radio waves and the ionospheric disturbances are capable of causing range errors, rapid phase and amplitude fluctuations (radio scintillations of satellite signals that may lead to degradation of the system performance, its accuracy and reliability. The cause of such disturbances should be sought in the processes originating in the Sun. Numerous studies on these phenomena have been already carried out at a broad international level, in order to measure/estimate these space weather induced effects, to forecast them, and to understand and mitigate their impact on present-day technological systems. SWIPPA (Space Weather Impact on Precise Positioning Applications is a pilot project jointly supported by the German Aerospace Centre (DLR and the European Space Agency (ESA. The project aims at establishing, operating, and evaluating a specific space-weather monitoring service that can possibly lead to improving current positioning applications based on Global Navigation Satellite Systems (GNSS. This space weather service provides GNSS users with essential expert information delivered in the form of several products - maps of TEC values, TEC spatial and temporal gradients, alerts for ongoing/oncoming ionosphere disturbances, etc.

  7. Status of Core Products of the International GNSS Service

    Science.gov (United States)

    Choi, K. K.

    2014-12-01

    The International GNSS Service (IGS) has been providing high accuracy GNSS orbits, clocks and Earth Rotation Parameters (ERP) in three different time intervals. The quality of the IGS core products are regularly monitored since 2010, and the level of accuracies has not been changed noticeably. The Final and Rapid orbit's accuracies are known to be about ~2.5 cm and the near-real time (observed) Ultra-rapid orbit is about 3 cm. The real-time orbits obtained by propagating the Ultra-rapid orbits shows an accuracy of about 5 cm. The most significant error source of the real-time orbit is the sub-daily variation of the Earth orientation. Number of IGS08 core sites has been decreasing with the rate of ~0.13 stations per week due to equipment changes and natural disasters such as Earthquakes. This paper summarizes the quality state of the IGS core products for 2014, and the upcoming new official product IGV, Glonass Ultra-rapid orbit product which have been experimental for last 4 years. Eight IGS Analysis Centers (ACs) have completed their efforts to participate in the second reprocessing campaign (repro2). Based on their input, this paper summarizes the models and methodologies each AC have adopted for this campaign.

  8. A New Online Service for the Validation of Multi-GNSS Orbits Using SLR

    Directory of Open Access Journals (Sweden)

    Radosław Zajdel

    2017-10-01

    Full Text Available In the last decade, we have been witnessing a rapid development of the constellations of Global and Regional Navigation Satellite Systems (GNSS/RNSS. Besides the well-known GPS and GLONASS, newly developed systems such as Galileo, BeiDou, QZSS and NAVIC have become increasingly important. All satellites of new GNSS are equipped with laser retroreflector arrays (LRA dedicated to Satellite Laser Ranging (SLR. SLR allows, e.g., an independent validation of microwave-based orbit products. Therefore, a fully operational online service called the multi-GNSS Orbit Validation Visualizer Using SLR (GOVUS has been developed allowing for near real-time analysis of the quality of multi-GNSS orbits. The mean offsets of SLR residuals for Center for Orbit Determination in Europe (CODE orbits in 2016 are at the level of −8, −38, −14, and −107 mm, for BeiDou, Galileo, GLONASS, and QZSS, respectively, with the standard deviations of 66, 36, 29, and 100 mm. Moreover, GOVUS can be used as a database containing information on equipment used at SLR stations and multi-GNSS satellite parameters. This paper includes a comprehensive description of the functionality and the structure of the developed service with exemplary analyses. The paper points out the most critical issues, limitations and challenges of multi-GNSS and SLR tracking network in the context of the SLR orbit validation. The goal of the paper and GOVUS itself is to determine: (1 what is the current quality of multi-GNSS orbits validated using SLR results; (2 what kinds of systematic errors can affect GNSS orbits and SLR observations; and (3 how to provide the online analysis tools to the broadest possible multi-GNSS community. The service has been officially operating since March 2017 as the Associate Analysis Center of the International Laser Ranging Service (ILRS ACC.

  9. Debris flow cartography using differential GNSS and Theodolite measurements

    Science.gov (United States)

    Khazaradze, Giorgi; Guinau, Marta; Calvet, Jaume; Furdada, Gloria; Victoriano, Ane; Génova, Mar; Suriñach, Emma

    2016-04-01

    The presented results form part of a CHARMA project, which pursues a broad objective of reducing damage caused by uncontrolled mass movements, such as rockfalls, snow avalanches and debris flows. Ultimate goal of the project is to contribute towards the establishment of new scientific knowledge and tools that can help in the design and creation of early warning systems. Here we present the specific results that deal with the application of differential GNSS and classical geodetic (e.g. theodolite) methods for mapping debris and torrential flows. Specifically, we investigate the Portainé stream located in the Pallars Sobirà region of Catalonia (Spain), in the eastern Pyrenees. In the last decade more than ten debris-flow type phenomena have affected the region, causing considerable economic losses. Since early 2014, we have conducted several field campaigns within the study area, where we have employed a multi-disciplinary approach, consisting of geomorphological, dendro-chronological and geodetic methods, in order to map the river bed and reconstruct the history of the extreme flooding and debris flow events. Geodetic studies included several approaches, using the classical and satellite based methods. The former consisted of angle and distance measurements between the Geodolite 502 total station and the reflecting prisms placed on top of the control points located within the riverbed. These type of measurements are precise, although present several disadvantages such as the lack of absolute coordinates that makes the geo-referencing difficult, as well as a relatively time-consuming process that involves two persons. For this reason, we have also measured the same control points using the differential GNSS system, in order to evaluate the feasibility of replacing the total station measurements with the GNSS. The latter measuring method is fast and can be conducted by one person. However, the fact that the study area is within the riverbed, often below the trees

  10. Tag-gas encapsulated assembly

    International Nuclear Information System (INIS)

    Murabayashi, Hideki.

    1980-01-01

    Purpose: To ensure tag-gas release upon failure of a fuel cladding tube with no effects from viscosity and surface tension of low melting alloy, by engaging a closing valve body to the inside surface of an opening of the assembly and securing it by means of a low melting alloy. Constitution: A tag-gas capsule is fabricated from a hollow cylindrical body having an outer diameter corresponding to the inner diameter of a fuel pin cladding tube and welded with an upper end plug and a lower end plug. The upper end plug is formed with an opening of a small diameter at the center and with a concaved face at the inside surface. A valve body of a shape just fitting to the concaved face is engaged and secured by means of a low melting alloy to the inside surface of the upper end plug. When the temperature of the capsule arrives at a predetermined temperature to fuse the alloy, the self weight of the valve body overcomes the viscosity and the surface tension of the alloy and the valve body falls instantly. (Sekiya, K.)

  11. Learner Corpora without Error Tagging

    Directory of Open Access Journals (Sweden)

    Rastelli, Stefano

    2009-01-01

    Full Text Available The article explores the possibility of adopting a form-to-function perspective when annotating learner corpora in order to get deeper insights about systematic features of interlanguage. A split between forms and functions (or categories is desirable in order to avoid the "comparative fallacy" and because – especially in basic varieties – forms may precede functions (e.g., what resembles to a "noun" might have a different function or a function may show up in unexpected forms. In the computer-aided error analysis tradition, all items produced by learners are traced to a grid of error tags which is based on the categories of the target language. Differently, we believe it is possible to record and make retrievable both words and sequence of characters independently from their functional-grammatical label in the target language. For this purpose at the University of Pavia we adapted a probabilistic POS tagger designed for L1 on L2 data. Despite the criticism that this operation can raise, we found that it is better to work with "virtual categories" rather than with errors. The article outlines the theoretical background of the project and shows some examples in which some potential of SLA-oriented (non error-based tagging will be possibly made clearer.

  12. Developing a Robust, Interoperable GNSS Space Service Volume (SSV) for the Global Space User Community

    Science.gov (United States)

    Bauer, Frank H.; Parker, Joel J. K.; Welch, Bryan; Enderle, Werner

    2017-01-01

    For over two decades, researchers, space users, Global Navigation Satellite System (GNSS) service providers, and international policy makers have been working diligently to expand the space-borne use of the Global Positioning System (GPS) and, most recently, to employ the full complement of GNSS constellations to increase spacecraft navigation performance. Space-borne Positioning, Navigation, and Timing (PNT) applications employing GNSS are now ubiquitous in Low Earth Orbit (LEO). GNSS use in space is quickly expanding into the Space Service Volume (SSV), the signal environment in the volume surrounding the Earth that enables real-time PNT measurements from GNSS systems at altitudes of 3000 km and above. To support the current missions and planned future missions within the SSV, initiatives are being conducted in the United States and internationally to ensure that GNSS signals are available, robust, and yield precise navigation performance. These initiatives include the Interagency Forum for Operational Requirements (IFOR) effort in the United States, to support GPS SSV signal robustness through future design changes, and the United Nations-sponsored International Committee on GNSS (ICG), to coordinate SSV development across all international GNSS constellations and regional augmentations. The results of these efforts have already proven fruitful, enabling new missions through radically improved navigation and timing performance, ensuring quick recovery from trajectory maneuvers, improving space vehicle autonomy and making GNSS signals more resilient from potential disruptions. Missions in the SSV are operational now and have demonstrated outstanding PNT performance characteristics; much better than what was envisioned less than a decade ago. The recent launch of the first in a series of US weather satellites will employ the use of GNSS in the SSV to substantially improve weather prediction and public-safety situational awareness of fast moving events, including

  13. Energy calibration of the photon tagging system

    International Nuclear Information System (INIS)

    Endo, Satoru; Niki, Kazuaki; Suzuki, Akira

    1989-07-01

    There is a photon tagging system at the 1.3 GeV Electron Synchrotron (ES), and the system is designed to produce a monochromatic photon beam with an energy resolution of ±5 MeV. To calibrate the energies of tagged photons produced by this system, electron beams of various energies from ES are injected directly into this system. As the result of this calibration, we conclude that the photon tagging system has the performance of designed values. (author)

  14. B-tagging in CMS at LHC

    CERN Document Server

    Cucciarelli, S

    2003-01-01

    This report provides a review of the main algorithms for offline inclusive b-tagging developed within the CMS community. Two b-tag algorithms, one based on the impact parameter measurement and the other based on the secondary vertices are discussed. The performance of these algorithms are presented for several jet transverse energies and pseudorapidity regions. An additional decay length based b-tag is also described and its preliminary performance is presented. (4 refs) .

  15. Ear-to-Ear On-Body Channel Fading in the ISM-band for Tangentially-Polarized Antennas

    DEFF Research Database (Denmark)

    Kvist, Søren Helstrup; Thaysen, Jesper; Jakobsen, Kaj Bjarne

    2011-01-01

    The ear-to-ear on-body channel fading has been studied in the ISM-band. The ear-to-ear path gain was measured on six persons in an indoor environment for a duration of 200 s. The channel fading has been characterized in terms of empirical cumulative distribution functions (CDF), average fade...

  16. Predictions of middle-ear and passive cochlear mechanics using a finite element model of the pediatric ear.

    Science.gov (United States)

    Wang, Xuelin; Keefe, Douglas H; Gan, Rong Z

    2016-04-01

    A finite element (FE) model was developed based on histological sections of a temporal bone of a 4-year-old child to simulate middle-ear and cochlear function in ears with normal hearing and otitis media. This pediatric model of the normal ear, consisting of an ear canal, middle ear, and spiral cochlea, was first validated with published energy absorbance (EA) measurements in young children with normal ears. The model was used to simulate EA in an ear with middle-ear effusion, whose results were compared to clinical EA measurements. The spiral cochlea component of the model was constructed under the assumption that the mechanics were passive. The FE model predicted middle-ear transfer functions between the ear canal and cochlea. Effects of ear structure and mechanical properties of soft tissues were compared in model predictions for the pediatric and adult ears. EA responses are predicted to differ between adult and pediatric ears due to differences in the stiffness and damping of soft tissues within the ear, and any residual geometrical differences between the adult ear and pediatric ear at age 4 years. The results have significance for predicting effects of otitis media in children.

  17. Graph based techniques for tag cloud generation

    DEFF Research Database (Denmark)

    Leginus, Martin; Dolog, Peter; Lage, Ricardo Gomes

    2013-01-01

    Tag cloud is one of the navigation aids for exploring documents. Tag cloud also link documents through the user defined terms. We explore various graph based techniques to improve the tag cloud generation. Moreover, we introduce relevance measures based on underlying data such as ratings...... or citation counts for improved measurement of relevance of tag clouds. We show, that on the given data sets, our approach outperforms the state of the art baseline methods with respect to such relevance by 41 % on Movielens dataset and by 11 % on Bibsonomy data set....

  18. Sensor-based material tagging system

    International Nuclear Information System (INIS)

    Vercellotti, L.C.; Cox, R.W.; Ravas, R.J.; Schlotterer, J.C.

    1991-01-01

    Electronic identification tags are being developed for tracking material and personnel. In applying electronic identification tags to radioactive materials safeguards, it is important to measure attributes of the material to ensure that the tag remains with the material. The addition of a microcontroller with an on-board analog-to-digital converter to an electronic identification tag application-specific integrated-circuit has been demonstrated as means to provide the tag with sensor data. Each tag is assembled into a housing, which serves as a scale for measuring the weight of a paint-can-sized container and its contents. Temperature rise of the can above ambient is also measured, and a piezoelectric detector detects disturbances and immediately puts the tag into its alarm and beacon mode. Radiation measurement was also considered, but the background from nearby containers was found to be excessive. The sensor-based tagging system allows tracking of the material in cans as it is stored in vaults or is moved through the manufacturing process. The paper presents details of the sensor-based material tagging system and describes a demonstration system

  19. Using Interference to Block RFID Tags

    DEFF Research Database (Denmark)

    Krigslund, Rasmus; Popovski, Petar; Pedersen, Gert Frølund

    We propose a novel method to block RFID tags from responding, using intentional interference. We focus on the experimental evaluation, where we impose interference on the download and uplink, respectively. The results are positive, where modulated CCI shows most effective to block a tag.......We propose a novel method to block RFID tags from responding, using intentional interference. We focus on the experimental evaluation, where we impose interference on the download and uplink, respectively. The results are positive, where modulated CCI shows most effective to block a tag....

  20. Discharge residence of TLD tagged fish

    International Nuclear Information System (INIS)

    Romberg, G.P.; Prepejchal, W.

    1974-01-01

    Although visual observations suggested that fish remained in the discharge for considerable periods, temperature-sensitive tags indicated the majority of fish spend less than 50 hr or 10 percent of the time at discharge temperatures. During 1974 a second fish tagging study was conducted, using temperature-sensitive tags to yield discharge residence times of Lake Michigan salmonids at Point Beach thermal discharge. Preliminary results revealed that many fish tag values were close to Unit I line indicating that calculated maximum discharge residence times for these fish will be nearly 100 percent of the elapsed time

  1. [Functional model of the middle ear ossicles].

    Science.gov (United States)

    Satoda, Takahiro; Shimoe, Saiji; Makihira, Seicho; Tamamoto, Mitsuhiro; Matsumoto, Atsue; Hara, Kumiko; Noso, Maki; Niitani, Yoshie; Sugiyama, Masaru; Takemoto, Toshinobu; Murayama, Takeshi; Amano, Hideaki; Nikawa, Hiroki

    2009-06-01

    In students' dissection practice, it is very difficult to teach students the structures and functions of the middle ear ossicles. The middle ear ossicles are too small to explain their structures and functions. Models are useful in explaining these points, but there have been no models that accurately explain the movements of the middle ear ossicles and the functions of the muscles in the middle ear. This time, we have made a model of middle ear ossicles. Our ear ossicles are made of paper-mache with metal in it. The incudomalleolar and incudostapedial articulations are made of rubber. The tensor tympani and the stapedius muscles are made of wire and the two wires can be fixed by cord stoppers. Our model explains clearly the following mechanisms of the middle ear ossicles. 1. The mechanism of sound conduction system. When the sound vibrates the tympanic membrane, malleus and incus rotate together. The long process of the incus pushes the head of the stapes. The sound is amplified by leverage. 2. Attenuation of sound by contractions of tensor tympani and stapedius muscles. When a loud sound is transmitted through the ossicular system, the tensor tympani muscle pulls the malleus inward while the stapedius muscle pulls the stapes outward. These two forces oppose each other and increase rigidity of the ossicular system, thus reducing the ossicular conduction. 3. The mechanism of how paralysis of stapedius muscle, caused by an injury to the facial nerve, results in hyperacusis. 4. This model also suggests a possible reason why the pars lucida of the tympanic membrane exists.

  2. Prenatal evaluation of the middle ear and diagnosis of middle ear hypoplasia using MRI

    Energy Technology Data Exchange (ETDEWEB)

    Katorza, Eldad; Nahama-Allouche, Catherine; Ducou le Pointe, Hubert; Garel, Catherine [Hopital d' Enfants Armand-Trousseau, Service de Radiologie, Paris (France); Castaigne, Vanina [Hopital Saint-Antoine, Service de Gynecologie-Obstetrique, Paris (France); Gonzales, Marie; Marlin, Sandrine [Hopital d' Enfants Armand-Trousseau, Service de Genetique et Embryologie medicales, Paris (France); Galliani, Eva [Hopital d' Enfants Armand-Trousseau, Service de Chirurgie maxillo-faciale, Paris (France); Jouannic, Jean-Marie; Rosenblatt, Jonathan [Hopital d' Enfants Armand-Trousseau, Service de Gynecologie-Obstetrique, Centre pluridisciplinaire de diagnostic prenatal, Paris (France)

    2011-05-15

    Analysis of the middle ear with fetal MRI has not been previously reported. To show the contribution of fetal MRI to middle ear imaging. The tympanic cavity was evaluated in 108 fetal cerebral MRI examinations (facial and/or cerebral malformation excluded) and in two cases, one of Treacher Collins syndrome (case 1) and the other of oculo-auriculo-vertebral (OUV) spectrum (case 2) with middle ear hypoplasia identified by MRI at 27 and 36 weeks' gestation, respectively. In all 108 fetuses (mean gestational age 32.5 weeks), the tympanic cavity and T2 hypointensity related to the ossicles were well visualised on both sides. Case 1 had micro/retrognathia and bilateral external ear deformity and case 2 had retrognathism with a left low-set and deformed ear. MRI made it possible to recognize the marked hypoplasia of the tympanic cavity, which was bilateral in case 1 and unilateral in case 2. Both syndromes are characterized by craniofacial abnormalities including middle ear hypoplasia, which cannot be diagnosed with US. The middle ear cavity can be visualized with fetal MRI. We emphasize the use of this imaging modality in the diagnosis of middle ear hypoplasia. (orig.)

  3. The Effects of Silicone and Acrylic Ear Mold Materials on Outer Ear Canal Resonance Characteristics.

    Science.gov (United States)

    Alnıaçık Erdoğan, Asuman; Arslan, Şeyda Nur

    2016-08-01

    The aim of this study is to investigate the effects of earmolds made of silicone and acrylic on outer ear canal resonance characteristics in terms of resonance frequency and amplitude measured in a hearing aid fitting. Outer ear canal resonance frequencies and amplitudes in open ears and those measured with silicone and acrylic ear molds were obtained from 30 participants between the ages of 20 and 25 years (average age, 22.0 years; 18 females and 12 males) with a real ear gain measurement. To observe the changes depending on probe tube placement, test-retest variation was investigated in 10 participants before the study. There was no statistically significant difference between open ear canal resonance frequencies and those measured with silicone and acrylic earmolds (p>0.05). the silicone earmold resonance amplitude values were statistically significantly lower than the open ear canal resonance amplitudes when compared to those of the acrylic earmolds (p<0.05). Depending on the changes occurring in outer ear resonance features as a result of earmold materials used in hearing aid fittings, the application of earmolds should be done by experienced specialists.

  4. AATR an ionospheric activity indicator specifically based on GNSS measurements

    Science.gov (United States)

    Juan, José Miguel; Sanz, Jaume; Rovira-Garcia, Adrià; González-Casado, Guillermo; Ibáñez, D.; Perez, R. Orus

    2018-03-01

    This work reviews an ionospheric activity indicator useful for identifying disturbed periods affecting the performance of Global Navigation Satellite System (GNSS). This index is based in the Along Arc TEC Rate (AATR) and can be easily computed from dual-frequency GNSS measurements. The AATR indicator has been assessed over more than one Solar Cycle (2002-2017) involving about 140 receivers distributed world-wide. Results show that it is well correlated with the ionospheric activity and, unlike other global indicators linked to the geomagnetic activity (i.e. DST or Ap), it is sensitive to the regional behaviour of the ionosphere and identifies specific effects on GNSS users. Moreover, from a devoted analysis of different Satellite Based Augmentation System (SBAS) performances in different ionospheric conditions, it follows that the AATR indicator is a very suitable mean to reveal whether SBAS service availability anomalies are linked to the ionosphere. On this account, the AATR indicator has been selected as the metric to characterise the ionosphere operational conditions in the frame of the European Space Agency activities on the European Geostationary Navigation Overlay System (EGNOS). The AATR index has been adopted as a standard tool by the International Civil Aviation Organization (ICAO) for joint ionospheric studies in SBAS. In this work we explain how the AATR is computed, paying special attention to the cycle-slip detection, which is one of the key issues in the AATR computation, not fully addressed in other indicators such as the Rate Of change of the TEC Index (ROTI). After this explanation we present some of the main conclusions about the ionospheric activity that can extracted from the AATR values during the above mentioned long-term study. These conclusions are: (a) the different spatial correlation related with the MOdified DIP (MODIP) which allows to clearly separate high, mid and low latitude regions, (b) the large spatial correlation in mid

  5. CODE's new solar radiation pressure model for GNSS orbit determination

    Science.gov (United States)

    Arnold, D.; Meindl, M.; Beutler, G.; Dach, R.; Schaer, S.; Lutz, S.; Prange, L.; Sośnica, K.; Mervart, L.; Jäggi, A.

    2015-08-01

    The Empirical CODE Orbit Model (ECOM) of the Center for Orbit Determination in Europe (CODE), which was developed in the early 1990s, is widely used in the International GNSS Service (IGS) community. For a rather long time, spurious spectral lines are known to exist in geophysical parameters, in particular in the Earth Rotation Parameters (ERPs) and in the estimated geocenter coordinates, which could recently be attributed to the ECOM. These effects grew creepingly with the increasing influence of the GLONASS system in recent years in the CODE analysis, which is based on a rigorous combination of GPS and GLONASS since May 2003. In a first step we show that the problems associated with the ECOM are to the largest extent caused by the GLONASS, which was reaching full deployment by the end of 2011. GPS-only, GLONASS-only, and combined GPS/GLONASS solutions using the observations in the years 2009-2011 of a global network of 92 combined GPS/GLONASS receivers were analyzed for this purpose. In a second step we review direct solar radiation pressure (SRP) models for GNSS satellites. We demonstrate that only even-order short-period harmonic perturbations acting along the direction Sun-satellite occur for GPS and GLONASS satellites, and only odd-order perturbations acting along the direction perpendicular to both, the vector Sun-satellite and the spacecraft's solar panel axis. Based on this insight we assess in the third step the performance of four candidate orbit models for the future ECOM. The geocenter coordinates, the ERP differences w. r. t. the IERS 08 C04 series of ERPs, the misclosures for the midnight epochs of the daily orbital arcs, and scale parameters of Helmert transformations for station coordinates serve as quality criteria. The old and updated ECOM are validated in addition with satellite laser ranging (SLR) observations and by comparing the orbits to those of the IGS and other analysis centers. Based on all tests, we present a new extended ECOM which

  6. AATR an ionospheric activity indicator specifically based on GNSS measurements

    Directory of Open Access Journals (Sweden)

    Juan José Miguel

    2018-01-01

    Full Text Available This work reviews an ionospheric activity indicator useful for identifying disturbed periods affecting the performance of Global Navigation Satellite System (GNSS. This index is based in the Along Arc TEC Rate (AATR and can be easily computed from dual-frequency GNSS measurements. The AATR indicator has been assessed over more than one Solar Cycle (2002–2017 involving about 140 receivers distributed world-wide. Results show that it is well correlated with the ionospheric activity and, unlike other global indicators linked to the geomagnetic activity (i.e. DST or Ap, it is sensitive to the regional behaviour of the ionosphere and identifies specific effects on GNSS users. Moreover, from a devoted analysis of different Satellite Based Augmentation System (SBAS performances in different ionospheric conditions, it follows that the AATR indicator is a very suitable mean to reveal whether SBAS service availability anomalies are linked to the ionosphere. On this account, the AATR indicator has been selected as the metric to characterise the ionosphere operational conditions in the frame of the European Space Agency activities on the European Geostationary Navigation Overlay System (EGNOS. The AATR index has been adopted as a standard tool by the International Civil Aviation Organization (ICAO for joint ionospheric studies in SBAS. In this work we explain how the AATR is computed, paying special attention to the cycle-slip detection, which is one of the key issues in the AATR computation, not fully addressed in other indicators such as the Rate Of change of the TEC Index (ROTI. After this explanation we present some of the main conclusions about the ionospheric activity that can extracted from the AATR values during the above mentioned long-term study. These conclusions are: (a the different spatial correlation related with the MOdified DIP (MODIP which allows to clearly separate high, mid and low latitude regions, (b the large spatial correlation in

  7. Engineering the ATLAS TAG Browser

    International Nuclear Information System (INIS)

    Zhang Qizhi

    2011-01-01

    ELSSI is a web-based event metadata (TAG) browser and event-level selection service for ATLAS. In this paper, we describe some of the challenges encountered in the process of developing ELSSI, and the software engineering strategies adopted to address those challenges. Approaches to management of access to data, browsing, data rendering, query building, query validation, execution, connection management, and communication with auxiliary services are discussed. We also describe strategies for dealing with data that may vary over time, such as run-dependent trigger decision decoding. Along with examples, we illustrate how programming techniques in multiple languages (PHP, JAVASCRIPT, XML, AJAX, and PL/SQL) have been blended to achieve the required results. Finally, we evaluate features of the ELSSI service in terms of functionality, scalability, and performance.

  8. To tag or not to tag: animal welfare, conservation and stakeholder considerations in fish tracking studies that use electronic tags

    Energy Technology Data Exchange (ETDEWEB)

    Cooke, Steven J.; Nguyen, Vivian M.; Murchie, Karen J.; Thiem, Jason D.; Donaldson, Michael R.; Hinch, Scott G.; Brown, Richard S.; Fisk, Aaron

    2013-11-01

    The advent and widespread adoption of electronic tags (including biotelemetry and biologging devices) for tracking animals has provided unprecedented information on the biology, management, and conservation of fish in the world’s oceans and inland waters. However, use of these tools is not without controversy. Even when scientific and management objectives may best be achieved using electronic tags, it is increasingly important to further consider other factors such as the welfare of tagged animals (i.e., the role of training and science-based surgical guidelines, anesthetic use, inability to maintain sterile conditions in field environments), the ethics of tagging threatened species vs. using surrogates, stakeholder perspectives on tagging (including aboriginals), as well as use of data emanating from such studies (e.g., by fishers to facilitate exploitation). Failure to do so will have the potential to create conflict and undermine scientific, management and public confidence in the use of this powerful tool. Indeed, there are already a number of examples of where tracking studies using electronic tags have been halted based on concerns raised by researchers, authorities, or stakeholders. Here we present a candid evaluation of several factors that should be considered when determining when to tag or not to tag fish with electronic devices. It is not our objective to judge the merit of previous studies. Rather, we hope to stimulate debate and discussion regarding the use of electronic tags to study fish. Relatedly, there is a need for more research to address these questions (e.g., what level of cleanliness is needed when conducting surgeries, what type of training should be required for fish surgery) including human dimensions studies to understand perspectives of different actors including society as a whole with respect to tagging and tracking studies.

  9. Information fusion of GNSS sensor readings, field notes, and expert's a priori knowledge

    NARCIS (Netherlands)

    Vasenev, Alexandr; Ionita, Dan; Bijleveld, Frank; Hartmann, Timo; Doree, Andries G.; Suter, G.; de Wilde, P.; Rafiq, Y.

    2013-01-01

    Documenting machinery movements by using positioning technologies, such as global navigation satellite systems (GNSS), is essential to understand and further improve construction processes. However, before measurements can be meaningfully analysed the documented movements should be filtered to

  10. Analysis of Ionospheric Scintillation Characteristics in Sub-Antarctica Region with GNSS Data at Macquarie Island.

    Science.gov (United States)

    Guo, Kai; Liu, Yang; Zhao, Yan; Wang, Jinling

    2017-01-12

    Ionospheric scintillation has a great impact on radio propagation and electronic system performance, thus is extensively studied currently. The influence of scintillation on Global Navigation Satellite System (GNSS) is particularly evident, making GNSS an effective medium to study characteristics of scintillation. Ionospheric scintillation varies greatly in relation with temporal and spatial distribution. In this paper, both temporal and spatial characteristics of scintillation are investigated based on Macquarie Island's GNSS scintillation data collected from 2011 to 2015. Experiments demonstrate that occurrence rates of amplitude scintillation have a close relationship with solar activity, while phase scintillation is more likely to be generated by geomagnetic activity. In addition, scintillation distribution behaviors related to elevation and azimuth angles are statistically analyzed for both amplitude and phase scintillation. The proposed work is valuable for a deeper understanding of theoretical mechanisms of ionospheric scintillation in this region, and provides a reference for GNSS applications in certain regions around sub-Antarctica.

  11. GPS/GNSS Antenna Characterization : GPS-ABC Workshop V RTCA Washington, DC October 14, 2016.

    Science.gov (United States)

    2016-10-14

    One component of the Department of Transportations GPS Adjacent Band : Compatibility Study is the characterization of GPS/GNSS receiver antennas : Such characterization is needed to: : Compare radiated and conducted (wired) test result...

  12. Maintenance of the Photovolatic Plants Using UAV Equipped with Low-cost GNSS RTK Receiver

    DEFF Research Database (Denmark)

    Bilal, Muhammad; Prasad, Ramjee; Nisi, Marco

    2017-01-01

    Global Navigation Satellite System (GNSS) Real Time Kinematic (RTK) employs high-end dual-frequency receivers and antennas to deliver precise positioning that, in some way, restricts the use of GNSSRTKto a subset of user market due to very high cost. The emerging mass-market user applications......, however, require centimeter-positioning accuracy considering a cost-effective solution. This calls for low-cost GNSS RTK solutions to create new possibilities for mass-market user applications to make use of GNSS high accuracy positioning in a variety of ways. One of the applications, which makes use...... of low-cost GNSS RTK receiver, is the maintenance of photovoltaic (PV) plants using Unmanned Aerial Vehicle (UAV). This paper proposes a solution that aims at automating the maintenance of PV plant with enhanced reliability in a time and cost effective manner, which otherwise requires intermediate human...

  13. A Novel Range Compression Algorithm for Resolution Enhancement in GNSS-SARs.

    Science.gov (United States)

    Zheng, Yu; Yang, Yang; Chen, Wu

    2017-06-25

    In this paper, a novel range compression algorithm for enhancing range resolutions of a passive Global Navigation Satellite System-based Synthetic Aperture Radar (GNSS-SAR) is proposed. In the proposed algorithm, within each azimuth bin, firstly range compression is carried out by correlating a reflected GNSS intermediate frequency (IF) signal with a synchronized direct GNSS base-band signal in the range domain. Thereafter, spectrum equalization is applied to the compressed results for suppressing side lobes to obtain a final range-compressed signal. Both theoretical analysis and simulation results have demonstrated that significant range resolution improvement in GNSS-SAR images can be achieved by the proposed range compression algorithm, compared to the conventional range compression algorithm.

  14. GNSS-based Observations and Simulations of Spectral Scintillation Indices in the Arctic Ionosphere

    DEFF Research Database (Denmark)

    Durgonics, Tibor; Hoeg, Per; von Benzon, Hans-Henrik

    , and development of data-driven methodologies to accurately localize ionospheric irregularities and simulate GNSS scintillation signals are highly desired. Ionospheric scintillations have traditionally been quantified by amplitude (S4) and phase scintillations (σφ). Our study focuses on the Arctic, where...... scintillations, especially phase scintillations, are prominent. We will present observations acquired from a network of Greenlandic GNSS stations, including 2D amplitude and phase scintillation index maps for representative calm and storm periods. In addition to the traditional indices described above, we....... The observations will then be compared to properties of simulated GNSS signals computed by the Fast Scintillation Mode (FSM). The FSM was developed to simulate ionospheric scintillations under different geophysical conditions, and is used to simulate GNSS signals with known scintillation characteristics...

  15. Low-set ears and pinna abnormalities

    Science.gov (United States)

    ... because they do not affect hearing. However, sometimes cosmetic surgery is recommended. Skin tags may be tied off, ... 5 years old. More severe abnormalities may require surgery for cosmetic reasons as well as for function. Surgery to ...

  16. Ear Acupuncture in European Traditional Medicine

    Directory of Open Access Journals (Sweden)

    Luigi Gori

    2007-01-01

    Full Text Available Auricular acupuncture is a diagnostic and treatment system based on normalizing the body's dysfunction through stimulation of definite points on the ear. Rudimentary forms of acupuncture which probably arose during the Stone Age have survived in many parts of the world right down to present day. It was used in the ancient Egypt, Rome, Greece and all the Mediterranean area. It is a microacupuncture technique similar to reflexology, and was first described in France in 1950 by Paul Nogier who is considered the Father of modern ear acupuncture. It was speculated that the technique works because groups of pluripotent cells contain information from the whole organism and create regional organization centers representing different parts of the body. Nevertheless stimulation of a reflex point in the ear seems relieve symptoms of distant pathologies. Modern research is confirming the efficacy of ear acupuncture for analgesia and anxiety related disease, while tobacco dependence and other substance abuse still need confirmation. Actually main methodological problems with auricular acupuncture are that exist too many maps with little agreement regarding point location in the ear, and that the correspondence or reflex systems does not correlated with modern knowledge of anatomy and physiology.

  17. CT of temporal bone - IV. inner ear

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Jae Yoon; Sung, Kyu Bo; Youn, Eun Kyoung; Park, Youn Kyeung; Lee, Young Uk [Koryo general Hospital, Seoul (Korea, Republic of)

    1990-07-15

    Temporal bone CT was done in 697 patients from April 1985 to October 1989. The abnormal findings were seen in 453 patients, which were chronic otitis media in 355 patients, fracture in 49 patients and congenital anomaly in 44 patients, etc. The abnormal findings of inner ear were observed on 46 patients. The results were summarized as follows : 1. The incidence of inner ear involvement by chronic otitis media was 7.3% (26/355 : labyrinthine fistula in 17 patients, labyrinthitis ossificans in 9 patients). Labyrinthine fistula was most commonly located on lateral semicircular canal (15/17, 88.2%). 2. Fusion of vestibule with lateral semicircular canal and formation of common cavity was demonstrated incidentally in 5 patients (0.7% of total number of temporal bone CT), and bilateral in 3 patients. 3. The incidence of inner ear anomaly in congenital ear anomaly was 11.4% (5/44). All cases were bilateral and three patients showed associated middle ear anomaly. 4. The incidence of involvement of bony labyrinth in temporal bone fracture was 10.2% (5/49). Labyrinthine fracture was seen all patients of transverse(3) and mixed fracture(1). In longitudinal fracture, labyrinthine fracture was seen in 2.2% (1/45). 5. Others were traumatic labyrinthitis ossificans(1), intracanalicular acoustic neuroma(3) and facial nerve neuroma(1)

  18. Evaluation of PIT-tagging in cyprinids

    DEFF Research Database (Denmark)

    Skov, Christian; Brodersen, J.; Brönmark, C.

    2005-01-01

    Laboratory and field experiments were used to investigate how different marking procedures, with 23 mm PIT (passive integrated transponders) - tags. affected mortality, body condition and tag expulsion in small roach Rutilus rutilus and rudd Scardinus erythrophthalmus (117 to 163 mm total length...

  19. The relationship between ear skin temperature and behavior of growing pigs

    DEFF Research Database (Denmark)

    Andersen, Heidi

    The aim of this research was to investigate the diurnal variation in the ear skin temperature and the lying behaviour at different environmental temperatures. Three repeated experiments were performed. In each experiment, 18 growing pigs were divided into three groups with six pigs each. The pigs...... have an average start weight of 75 +/- 5 kg. Each experimental period was 20 days. The temperature was changed from 18 ºC down to 10ºC and up again to 22ºC in two degrees steps. The pigs carried a special ear tag with a temperature sensor. The skin temperature at the ear was measured every three...... minutes and a mean temperature on the basis of five 3-minute values was computed and logged automatically into a computer. Behavior of the pigs was recorded for 24 hours at each set point temperature of 18ºC, 10ºC and 22ºC. General activity, lying posture and contact with pen matters were scored by 12 min...

  20. Evaluation of RTKLIB's Positioning Accuracy Using low-cost GNSS Receiver and ASG-EUPOS

    OpenAIRE

    Bartosz Wisniewski; Krzysztof Bruniecki; Marek Moszynski

    2013-01-01

    The paper focuses on a comparison of different positioning methods provided by free and open source software (FOSS) package called RTKLIB. The RTKLIB supports real-time and post-processed positioning. The most important modes of operation tested by the authors are Kinematic, Static, Fixed and Precise Point Positioning (PPP). The data for evaluation were obtained from low-cost Global Navigation Satellite System (GNSS) receiver. The tested receiver was based on the u-blox's LEA-6T GNSS module. ...

  1. An Open-Loop Vector Receiver Architecture for GNSS-Based Scintillation Monitoring

    OpenAIRE

    CURRAN JAMES THOMAS; BAVARO MICHELE; FORTUNY GUASCH Joaquim

    2014-01-01

    GNSS-based studies of the ionosphere are typically conducted using navigation receivers which track both the carrier and code phase either on a satellite-by-satellite basis, or collectively via a vector structure [3]. Information relating to phase and amplitude scintillation is gathered from the receiver’s estimate of the carrier phase and the receiver correlators values, respectively. The quality of these parameters, however, is directly influenced by how well the receiver can track the GNSS...

  2. Flicker Noise in GNSS Station Position Time Series: How much is due to Crustal Loading Deformations?

    Science.gov (United States)

    Rebischung, P.; Chanard, K.; Metivier, L.; Altamimi, Z.

    2017-12-01

    The presence of colored noise in GNSS station position time series was detected 20 years ago. It has been shown since then that the background spectrum of non-linear GNSS station position residuals closely follows a power-law process (known as flicker noise, 1/f noise or pink noise), with some white noise taking over at the highest frequencies. However, the origin of the flicker noise present in GNSS station position time series is still unclear. Flicker noise is often described as intrinsic to the GNSS system, i.e. due to errors in the GNSS observations or in their modeling, but no such error source has been identified so far that could explain the level of observed flicker noise, nor its spatial correlation.We investigate another possible contributor to the observed flicker noise, namely real crustal displacements driven by surface mass transports, i.e. non-tidal loading deformations. This study is motivated by the presence of power-law noise in the time series of low-degree (≤ 40) and low-order (≤ 12) Stokes coefficients observed by GRACE - power-law noise might also exist at higher degrees and orders, but obscured by GRACE observational noise. By comparing GNSS station position time series with loading deformation time series derived from GRACE gravity fields, both with their periodic components removed, we therefore assess whether GNSS and GRACE both plausibly observe the same flicker behavior of surface mass transports / loading deformations. Taking into account GRACE observability limitations, we also quantify the amount of flicker noise in GNSS station position time series that could be explained by such flicker loading deformations.

  3. Progress Report on the GROWTH (GNSS Reflectometry for Ocean Waves, Tides, and Height) Research Project

    Science.gov (United States)

    Kitazawa, Y.; Ichikawa, K.; Akiyama, H.; Ebinuma, T.; Isoguchi, O.; Kimura, N.; Konda, M.; Kouguchi, N.; Tamura, H.; Tomita, H.; Yoshikawa, Y.; Waseda, T.

    2016-12-01

    Global Navigation Satellite Systems (GNSS), such as GPS is a system of satellites that provide autonomous geo-spatial positioning with global coverage. It allows small electronic receivers to determine their location to high precision using radio signals transmitted from satellites, GNSS reflectometry (GNSS-R) involves making measurements from the reflections from the Earth of navigation signals from GNSS satellites. Reflected signals from sea surface are considered that those are useful to observe sea state and sea surface height. We have started a research program for GNSS-R applications on oceanographic observations under the contract with MEXT (Ministry of Education Culture, Sports, Science and Technology, JAPAN) and launched a Japanese research consortium, GROWTH (GNSS Reflectometry for Ocean Waves, Tides, and Height). It is aiming to evaluate the capabilities of GNSS-R observations for oceanographic phenomena with different time scales, such as ocean waves (1/10 to tens of seconds), tides (one or half days), and sea surface dynamic height (a few days to years). In situ observations of ocean wave spectrum, wind speed vertical profile, and sea surface height will be quantitatively compared with equivalent estimates from simultaneous GNSS-R measurements. The GROWTH project will utilize different types of observation platforms; marine observation towers (about 20 m height), multi-copters (about 100 to 150 m height), and much higher-altitude CYGNSS data. Cross-platform data, together with in situ oceanographic observations, will be compared after adequate temporal averaging that accounts differences of the footprint sizes and temporal and spatial scales of oceanographic phenomena. This paper will provide overview of the GROWTH project, preliminary test results, obtained by the multi-sensor platform at observation towers, suggest actual footprint sizes and identification of swell. Preparation status of a ground station which will be supplied to receive CYGNSS data

  4. Use of High Sensitivity GNSS Receiver Doppler Measurements for Indoor Pedestrian Dead Reckoning

    OpenAIRE

    Renaudin, Valérie; ZHE, He; PETOVELLO, Mark G.; Lachapelle, Gérard

    2013-01-01

    Dead-reckoning (DR) algorithms, which use self-contained inertial sensors combined with gait analysis, have proven to be effective for pedestrian navigation purposes. In such DR systems, the primary error is often due to accumulated heading drifts. By tightly integrating global navigation satellite system (GNSS) Doppler measurements with DR, such accumulated heading errors can usually be accurately compensated. Under weak signal conditions, high sensitivity GNSS (HSGNSS) receivers with block ...

  5. GNSS-Reflectometry with GEROS-ISS: Overview and recent results

    DEFF Research Database (Denmark)

    Wickert, Jens; Andersen, Ole Baltazar; G., Beyerle

    2015-01-01

    GEROS-ISS (GEROS hereafter) stands for GNSS REflectometry, Radio Occultation and Scatterometry onboard the International Space Station. It is a scientific experiment, proposed to the European Space Agency (ESA) in 2011 for installation aboard the ISS. The main focus of GEROS is the dedicated use...... of signals from the currently available Global Navigation Satellite Systems (GNSS) for remote sensing of the System Earth with focus to Climate Change characterisation. The GEROS mission idea and the current status are briefly reviewed....

  6. Availability of GNSS for Road Pricing in Copenhagen

    DEFF Research Database (Denmark)

    Jensen, Anna B. O.; Zabic, Martina; Overø, H. M.

    2005-01-01

    of evaluating whether stand alone GPS is feasible for operational road pricing in Copenhagen. The analyses show that the GPS satellite availability in the downtown streets is not sufficient to form the basis for an operational road pricing setup in Copenhagen. The narrow street canyons prevent a sufficient...... amount of satellite signals from reaching street level, and there are too many gabs in the position logs to implement a fair and reliable taxation scheme. The need for augmentation is evident, and with the advent of Galileo within a few years, it is relevant to investigate how integrated GPS....../Galileo receivers will change the situation. With a 3D city model of Copenhagen, a Galileo simulator, and a raytracing algorithm, an analysis of the GNSS availability in the streets of Copenhagen was carried out. The analysis is focusing on the number of visible satellites and the HDOP. The results show...

  7. Sensitivity analysis of the GNSS derived Victoria plate motion

    Science.gov (United States)

    Apolinário, João; Fernandes, Rui; Bos, Machiel

    2014-05-01

    Fernandes et al. (2013) estimated the angular velocity of the Victoria tectonic block from geodetic data (GNSS derived velocities) only.. GNSS observations are sparse in this region and it is therefore of the utmost importance to use the available data (5 sites) in the most optimal way. Unfortunately, the existing time-series were/are affected by missing data and offsets. In addition, some time-series were close to the considered minimal threshold value to compute one reliable velocity solution: 2.5-3.0 years. In this research, we focus on the sensitivity of the derived angular velocity to changes in the data (longer data-span for some stations) by extending the used data-span: Fernandes et al. (2013) used data until September 2011. We also investigate the effect of adding other stations to the solution, which is now possible since more stations became available in the region. In addition, we study if the conventional power-law plus white noise model is indeed the best stochastic model. In this respect, we apply different noise models using HECTOR (Bos et al. (2013), which can use different noise models and estimate offsets and seasonal signals simultaneously. The seasonal signal estimation is also other important parameter, since the time-series are rather short or have large data spans at some stations, which implies that the seasonal signals still can have some effect on the estimated trends as shown by Blewitt and Lavellee (2002) and Bos et al. (2010). We also quantify the magnitude of such differences in the estimation of the secular velocity and their effect in the derived angular velocity. Concerning the offsets, we investigate how they can, detected and undetected, influence the estimated plate motion. The time of offsets has been determined by visual inspection of the time-series. The influence of undetected offsets has been done by adding small synthetic random walk signals that are too small to be detected visually but might have an effect on the

  8. Sentiment topic mining based on comment tags

    Science.gov (United States)

    Zhang, Daohai; Liu, Xue; Li, Juan; Fan, Mingyue

    2018-03-01

    With the development of e-commerce, various comments based on tags are generated, how to extract valuable information from these comment tags has become an important content of business management decisions. This study takes HUAWEI mobile phone tags as an example using the sentiment analysis and topic LDA mining method. The first step is data preprocessing and classification of comment tag topic mining. And then make the sentiment classification for comment tags. Finally, mine the comments again and analyze the emotional theme distribution under different sentiment classification. The results show that HUAWEI mobile phone has a good user experience in terms of fluency, cost performance, appearance, etc. Meanwhile, it should pay more attention to independent research and development, product design and development. In addition, battery and speed performance should be enhanced.

  9. GNSS Radio Occultation Methods for CubeSat Missions: The University of Calgary and Spire Partnership

    Science.gov (United States)

    Skone, S.; Swab, M.; Platzer, P.; Johl, S.; Cappaert, J.

    2014-12-01

    In 2008, the University of Calgary deployed a low-cost commercial-off-the-shelf dual frequency GPS receiver onboard the CanX-2 nanosatellite, with the goal of demonstrating single-antenna single-receiver GNSS radio occultation capabilities. The team successfully produced ionospheric electron density profiles and continues to operate the CanX-2 GPS payload and collect reliable data six years into the mission. Recently the University of Calgary partnered with Spire to develop low-cost atmospheric sounding methods based on GNSS radio occultations for nanosatellite platforms. The rapidly increasing capabilities on nanosatellites with regards to power production, pointing accuracy and antenna sensitivities provide an ever more attractive platform to create relevant solutions for space and terrestrial weather data. This paper describes future mission concepts and capabilities for multi-GNSS methods to generate high-resolution atmospheric profiles. Building on lessons learned from CanX-2, the system requirements are defined and recommendations made for efficient GNSS payload operations. New methods are assessed for multi-frequency multi-constellation GNSS radio occultation approaches. Software and hardware simulations are conducted for validation of proposed methods using appropriate receiver architectures. Analyses include signal tracking for LEO trajectories (and Dopplers) and high-precision navigation solutions. Initial data analysis is also presented for a miniaturized, multi-frequency, software-­defined GNSS receiver currently operating onboard Spire's innovative CubeSat platform.

  10. Precise Positioning with Multi-GNSS and its Advantage for Seismic Parameters Inversion

    Science.gov (United States)

    Chen, K.; Li, X.; Babeyko, A. Y.; Ge, M.

    2015-12-01

    Together with the ongoing modernization of U.S. GPS and Russian GLONASS, the two new emerging global navigation satellite systems (BeiDou from China and Galileo from European Union) have already been running and multi-GNSS era is coming. Compared with single system, multi-GNSS can significantly improve the satellite visibility, optimize the spatial geometry, reduce dilution of precision and will be of great benefits to both scientific applications and engineering services. In this contribution, we focus mainly on its potential advantages for earthquake parameters estimation and tsunami early warning. First, we assess the precise positioning performance of multi-GNSS by an out-door experiment on a shaking table. Three positioning methods were used to retrieve the simulated seismic signal: precise point positioning (PPP), variometric approach for displacements analysis stand-alone engine (VADASE) and temporal point positioning (TPP). In addition to that, with respect to VADASE and TPP, we extended the original dual-frequency model to single-frequency model and then tested the algorithms. Accuracy, reliability, and continuity were evaluated and analyzed in detail accordingly. Our results revealed that multi-GNSS offer more precise and robust positioning results over GPS-only. At last, as a case study, multi-GNSS data recorded during 2014 Pisagua Earthquake were re-processed. Using co-seismic displacements from GPS and multi-GNSS, earthquake and the aftermath tsunami were inverted, respectively.

  11. Performance Improvement of Receivers Based on Ultra-Tight Integration in GNSS-Challenged Environments

    Directory of Open Access Journals (Sweden)

    Feng Qin

    2013-12-01

    Full Text Available Ultra-tight integration was first proposed by Abbott in 2003 with the purpose of integrating a global navigation satellite system (GNSS and an inertial navigation system (INS. This technology can improve the tracking performances of a receiver by reconfiguring the tracking loops in GNSS-challenged environments. In this paper, the models of all error sources known to date in the phase lock loops (PLLs of a standard receiver and an ultra-tightly integrated GNSS/INS receiver are built, respectively. Based on these models, the tracking performances of the two receivers are compared to verify the improvement due to the ultra-tight integration. Meanwhile, the PLL error distributions of the two receivers are also depicted to analyze the error changes of the tracking loops. These results show that the tracking error is significantly reduced in the ultra-tightly integrated GNSS/INS receiver since the receiver’s dynamics are estimated and compensated by an INS. Moreover, the mathematical relationship between the tracking performances of the ultra-tightly integrated GNSS/INS receiver and the quality of the selected inertial measurement unit (IMU is derived from the error models and proved by the error comparisons of four ultra-tightly integrated GNSS/INS receivers aided by different grade IMUs.

  12. Performance Improvement of Receivers Based on Ultra-Tight Integration in GNSS-Challenged Environments

    Science.gov (United States)

    Qin, Feng; Zhan, Xingqun; Du, Gang

    2013-01-01

    Ultra-tight integration was first proposed by Abbott in 2003 with the purpose of integrating a global navigation satellite system (GNSS) and an inertial navigation system (INS). This technology can improve the tracking performances of a receiver by reconfiguring the tracking loops in GNSS-challenged environments. In this paper, the models of all error sources known to date in the phase lock loops (PLLs) of a standard receiver and an ultra-tightly integrated GNSS/INS receiver are built, respectively. Based on these models, the tracking performances of the two receivers are compared to verify the improvement due to the ultra-tight integration. Meanwhile, the PLL error distributions of the two receivers are also depicted to analyze the error changes of the tracking loops. These results show that the tracking error is significantly reduced in the ultra-tightly integrated GNSS/INS receiver since the receiver's dynamics are estimated and compensated by an INS. Moreover, the mathematical relationship between the tracking performances of the ultra-tightly integrated GNSS/INS receiver and the quality of the selected inertial measurement unit (IMU) is derived from the error models and proved by the error comparisons of four ultra-tightly integrated GNSS/INS receivers aided by different grade IMUs.

  13. Rate-gyro-integral constraint for ambiguity resolution in GNSS attitude determination applications.

    Science.gov (United States)

    Zhu, Jiancheng; Li, Tao; Wang, Jinling; Hu, Xiaoping; Wu, Meiping

    2013-06-21

    In the field of Global Navigation Satellite System (GNSS) attitude determination, the constraints usually play a critical role in resolving the unknown ambiguities quickly and correctly. Many constraints such as the baseline length, the geometry of multi-baselines and the horizontal attitude angles have been used extensively to improve the performance of ambiguity resolution. In the GNSS/Inertial Navigation System (INS) integrated attitude determination systems using low grade Inertial Measurement Unit (IMU), the initial heading parameters of the vehicle are usually worked out by the GNSS subsystem instead of by the IMU sensors independently. However, when a rotation occurs, the angle at which vehicle has turned within a short time span can be measured accurately by the IMU. This measurement will be treated as a constraint, namely the rate-gyro-integral constraint, which can aid the GNSS ambiguity resolution. We will use this constraint to filter the candidates in the ambiguity search stage. The ambiguity search space shrinks significantly with this constraint imposed during the rotation, thus it is helpful to speeding up the initialization of attitude parameters under dynamic circumstances. This paper will only study the applications of this new constraint to land vehicles. The impacts of measurement errors on the effect of this new constraint will be assessed for different grades of IMU and current average precision level of GNSS receivers. Simulations and experiments in urban areas have demonstrated the validity and efficacy of the new constraint in aiding GNSS attitude determinations.

  14. Auto Guided Oil Palm Planter by using multi-GNSS

    International Nuclear Information System (INIS)

    Aini, I Nur; Aimrun W; Amin, M S M; Ezrin, M H; Shafri, H Z

    2014-01-01

    Planting is one of the most important operations in plantation because it could affect the total area of productivity since it is the starting point in cultivation. In oil palm plantation, lining and spacing of oil palm shall be laid out and coincided with the topographic area and a system of drains. Conventionally, planting of oil palm will require the polarization process in order to prevent and overcome the lack of influence of the sun rise and get a regular crop row. Polarization is done after the completion of the opening area by using the spike wood with 1 m length painted at the top and 100 m length of wire. This process will generally require at least five persons at a time to pull the wire and carry the spikes while the other two persons will act as observer and spikes craftsmen respectively with the ability of the team is 3ha/day. Therefore, the aim of this project is to develop the oil palm planting technique by using multi- GNSS (Global Navigation Satellite System). Generally, this project will involve five main steps mainly; design of planting pattern by using SOLIDWORKS software, determine the boundary coordinate of planting area, georeference process with ArcGIS, stakeout process with Tracy software and finally marking up the location with the wooden spikes. The results proved that the multi- GNSS is capable to provide the high accuracy with less than 1 m in precise positioning system without augmentation data. With the ability of one person, time taken to complete 70 m × 50 m planting area is 290 min, which is 25 min faster than using GPS (Global Positioning System) only

  15. Precise individualized armature for ear reconstruction

    Science.gov (United States)

    Evenhouse, Raymond J.; Chen, Xiaoming

    1991-04-01

    The cosmetic result of an ear restored surgically or via prosthetics is dependent on the surgeon''s ability to carve a precise cartilage armature at the time of surgery or the prosthetist''s ability to sculpt in wax an exact duplicate of the patient''s " missing" ear. Introducing CAD/CAM technology into the process benefits the esthetic outcome of these procedures. By utilizing serial section information derived from CAT MRI or moulage techniques a mirrorimage of the patient''s " donor" ear is generated. The resulting earform data is then used for the design of a cartilage armature produced by multi-axis milling or to produce by stereolithography a model which serves as the basis for a prosthesis.

  16. Tagged at first listen: an examination of social tagging practices in a music recommender system

    Directory of Open Access Journals (Sweden)

    Audrey Laplante

    2015-01-01

    Full Text Available http://dx.doi.org/10.5007/1518-2924.2015v20nesp1p33 Social tagging has become a very common way to index different types of resources on the web. Less prevalent in music than in other domains, social tagging is nevertheless used in a popular recommender system, Last.fm. Although the number of publications on tagging and folksonomies has exploded in the last few years, music tagging is still not well studied. In this paper, we present a study of tagging practices of Last.fm users. We examine the social tagging of songs during the first three months after their release. Our analysis shows that the release of a song triggers a burst in tagging activity that lasts two weeks, after what it decreases sharply and then remains fairly constant for the next ten weeks. We also find that a majority of songs do not get tagged during the first week and that tagging was positively related to popularity. Finally, we find that tags that have been frequently applied to a given song are more likely to be genre related, shorter in length, and relatively objective than tags that have been applied only once.

  17. Body lift, drag and power are relatively higher in large-eared than in small-eared bat species

    DEFF Research Database (Denmark)

    Håkansson, Jonas; Jakobsen, Lasse; Hedenström, Anders

    2017-01-01

    Bats navigate the dark using echolocation. Echolocation is enhanced by external ears, but external ears increase the projected frontal area and reduce the streamlining of the animal. External ears are thus expected to compromise flight efficiency, but research suggests that very large ears may...... mitigate the cost by producing aerodynamic lift. Here we compare quantitative aerodynamic measures of flight efficiency of two bat species, one large-eared (Plecotus auritus) and one small-eared (Glossophaga soricina), flying freely in a wind tunnel. We find that the body drag of both species is higher...... than previously assumed and that the large-eared species has a higher body drag coefficient, but also produces relatively more ear/body lift than the small-eared species, in line with prior studies on model bats. The measured aerodynamic power of P. auritus was higher than predicted from...

  18. A Phosphorylation Tag for Uranyl Mediated Protein Purification and Photo Assisted Tag Removal

    DEFF Research Database (Denmark)

    Zhang, Qiang; Jørgensen, Thomas. J. D.; Nielsen, Peter E

    2014-01-01

    of enzymes available for this purpose. In the present study, we demonstrate the utility of the divalent uranyl ion in a new procedure for protein purification and tag removal. By employment of a GFP (green florescence protein) recombinant protein we show that uranyl binding to a phosphorylated C-terminal tag......Most protein purification procedures include an affinity tag fused to either the N or C-terminal end of the protein of interest as well as a procedure for tag removal. Tag removal is not straightforward and especially tag removal from the C-terminal end is a challenge due to the characteristics...... enables target protein purification from an E. coli extract by immobilized uranyl affinity chromatography. Subsequently, the tag can be efficiently removed by UV-irradiation assisted uranyl photocleavage. We therefore suggest that the divalent uranyl ion (UO22+) may provide a dual function in protein...

  19. MRI measurement for inner ear structures

    International Nuclear Information System (INIS)

    Li Shuling; Liu Huaijun; Chi Chen; Qin Ruiping; Shi Zhaoxia

    2003-01-01

    Objective: To reconstruct the image of inner ear by using 3D-FASE heavily T 2 WI, and to establish MRI measurement criterion of inner ear structures. Methods: One hundred and six inner ears of 53 healthy volunteers underwent MRI heavily T2-weighted axial scanning by using 3D fast advanced spin echo sequence. All the original images were transferred to an online workstation. Analyze AVW software was used for image post-processing. All the structures of inner ear were reconstructed, rotated from various angles and measured by using maximum intensity projection (MIP). Results: (1) All the structures of inner ear and internal auditory channel (IAC) could be visualized clearly by using 3D-FASE heavily T 2 WI. (2) Using analysis of variance, there was no age, side or race-related difference in inner ear volume, but it was bigger in male than in female [(0.242 ± 0.0236) mm 3 (male) versus (0.226 ± 0.021) mm 3 (female)]. There was no age, side-related differences in three semicircular canal height and vestibule vertical diameter, but, again, they were bigger in male than in female. The height of upper, lateral and posterior semicircular canal were (5.511 ± 0.626) mm (male) versus (5.167 ± 0.357) mm (female); (3.763 ± 0.495) mm (male) versus (3.446 ± 0.405) mm (female); (5.227 ± 0.547) mm (male) versus (4.786 ± 0.500) mm (female). There was no age, sex or side-related differences in three semicircular canal diameter and cochlea. The diameter of upper, lateral and posterior semicircular canal were (1.06 ± 0.119) mm, (1.14 ± 0.181) mm, and (1.22 ± 0.196)mm; the external diameter of cochlea basal turn was (6.520 ± 0.475) mm, the diameter of cochlea basal turn was (1.413 ± 0.144) mm, and cochlea height was (4.100 ± 0.405) mm. Conclusion: (1) For the first time, the MRI measurement criterion of inner ear structures is established. (2) Vestibule and three semicircular canal of inner ear are bigger in male than in female

  20. The kidney and ear: emerging parallel functions.

    Science.gov (United States)

    Torban, Elena; Goodyer, Paul

    2009-01-01

    The association between renal dysplasia and minor malformations of the external ear is weak. However, there is a remarkable list of syndromes that link the kidney to the inner ear. To organize these seemingly disparate syndromes, we cluster representative examples into three groups: (a) syndromes that share pathways regulating development; (b) syndromes involving dysfunction of the primary cilium, which normally provides critical information to epithelial cells about the fluid in which they are bathed; (c) syndromes arising from dysfunction of specialized proteins that transport ions and drugs in and out of the extracellular fluid or provide structural support.

  1. Pop-up Archival Transmitting (PAT) fish tag data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The cooperative tagging center (CTC) began deploying electronic tags in 2002. To date over 300 tags have been deployed. The following species have been monitored:...

  2. Multi-GNSS real-time precise orbit/clock/UPD products and precise positioning service at GFZ

    Science.gov (United States)

    Li, Xingxing; Ge, Maorong; Liu, Yang; Fritsche, Mathias; Wickert, Jens; Schuh, Harald

    2016-04-01

    The rapid development of multi-constellation GNSSs (Global Navigation Satellite Systems, e.g., BeiDou, Galileo, GLONASS, GPS) and the IGS (International GNSS Service) Multi-GNSS Experiment (MGEX) bring great opportunities and challenges for real-time precise positioning service. In this contribution, we present a GPS+GLONASS+BeiDou+Galileo four-system model to fully exploit the observations of all these four navigation satellite systems for real-time precise orbit determination, clock estimation and positioning. A rigorous multi-GNSS analysis is performed to achieve the best possible consistency by processing the observations from different GNSS together in one common parameter estimation procedure. Meanwhile, an efficient multi-GNSS real-time precise positioning service system is designed and demonstrated by using the Multi-GNSS Experiment (MGEX) and International GNSS Service (IGS) data streams including stations all over the world. The addition of the BeiDou, Galileo and GLONASS systems to the standard GPS-only processing, reduces the convergence time almost by 70%, while the positioning accuracy is improved by about 25%. Some outliers in the GPS-only solutions vanish when multi-GNSS observations are processed simultaneous. The availability and reliability of GPS precise positioning decrease dramatically as the elevation cutoff increases. However, the accuracy of multi-GNSS precise point positioning (PPP) is hardly decreased and few centimeters are still achievable in the horizontal components even with 40° elevation cutoff.

  3. Prototyping a GNSS-Based Passive Radar for UAVs: An Instrument to Classify the Water Content Feature of Lands

    Directory of Open Access Journals (Sweden)

    Micaela Troglia Gamba

    2015-11-01

    Full Text Available Global Navigation Satellite Systems (GNSS broadcast signals for positioning and navigation, which can be also employed for remote sensing applications. Indeed, the satellites of any GNSS can be seen as synchronized sources of electromagnetic radiation, and specific processing of the signals reflected back from the ground can be used to estimate the geophysical properties of the Earth’s surface. Several experiments have successfully demonstrated GNSS-reflectometry (GNSS-R, whereas new applications are continuously emerging and are presently under development, either from static or dynamic platforms. GNSS-R can be implemented at a low cost, primarily if small devices are mounted on-board unmanned aerial vehicles (UAVs, which today can be equipped with several types of sensors for environmental monitoring. So far, many instruments for GNSS-R have followed the GNSS bistatic radar architecture and consisted of custom GNSS receivers, often requiring a personal computer and bulky systems to store large amounts of data. This paper presents the development of a GNSS-based sensor for UAVs and small manned aircraft, used to classify lands according to their soil water content. The paper provides details on the design of the major hardware and software components, as well as the description of the results obtained through field tests.

  4. Development of GNSS PWV information management system for very short-term weather forecast in the Korean Peninsula

    Science.gov (United States)

    Park, Han-Earl; Yoon, Ha Su; Yoo, Sung-Moon; Cho, Jungho

    2017-04-01

    Over the past decade, Global Navigation Satellite System (GNSS) was in the spotlight as a meteorological research tool. The Korea Astronomy and Space Science Institute (KASI) developed a GNSS precipitable water vapor (PWV) information management system to apply PWV to practical applications, such as very short-term weather forecast. The system consists of a DPR, DRS, and TEV, which are divided functionally. The DPR processes GNSS data using the Bernese GNSS software and then retrieves PWV from zenith total delay (ZTD) with the optimized mean temperature equation for the Korean Peninsula. The DRS collects data from eighty permanent GNSS stations in the southern part of the Korean Peninsula and provides the PWV retrieved from GNSS data to a user. The TEV is in charge of redundancy of the DPR. The whole process is performed in near real-time where the delay is ten minutes. The validity of the GNSS PWV was proved by means of a comparison with radiosonde data. In the experiment of numerical weather prediction model, the GNSS PWV was utilized as the initial value of the Weather Research & Forecasting (WRF) model for heavy rainfall event. As a result, we found that the forecasting capability of the WRF is improved by data assimilation of GNSS PWV.

  5. Prototyping a GNSS-Based Passive Radar for UAVs: An Instrument to Classify the Water Content Feature of Lands.

    Science.gov (United States)

    Gamba, Micaela Troglia; Marucco, Gianluca; Pini, Marco; Ugazio, Sabrina; Falletti, Emanuela; Lo Presti, Letizia

    2015-11-10

    Global Navigation Satellite Systems (GNSS) broadcast signals for positioning and navigation, which can be also employed for remote sensing applications. Indeed, the satellites of any GNSS can be seen as synchronized sources of electromagnetic radiation, and specific processing of the signals reflected back from the ground can be used to estimate the geophysical properties of the Earth's surface. Several experiments have successfully demonstrated GNSS-reflectometry (GNSS-R), whereas new applications are continuously emerging and are presently under development, either from static or dynamic platforms. GNSS-R can be implemented at a low cost, primarily if small devices are mounted on-board unmanned aerial vehicles (UAVs), which today can be equipped with several types of sensors for environmental monitoring. So far, many instruments for GNSS-R have followed the GNSS bistatic radar architecture and consisted of custom GNSS receivers, often requiring a personal computer and bulky systems to store large amounts of data. This paper presents the development of a GNSS-based sensor for UAVs and small manned aircraft, used to classify lands according to their soil water content. The paper provides details on the design of the major hardware and software components, as well as the description of the results obtained through field tests.

  6. Ground-Based Global Navigation Satellite System (GNSS) GLONASS Broadcast Ephemeris Data (hourly files) from NASA CDDIS

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset consists of ground-based Global Navigation Satellite System (GNSS) GLObal NAvigation Satellite System (GLONASS) Broadcast Ephemeris Data (hourly files)...

  7. Multislice spiral computed tomography imaging in congenital inner ear malformations.

    Science.gov (United States)

    Ma, Hui; Han, Ping; Liang, Bo; Tian, Zhi-liang; Lei, Zi-qiao; Kong, Wei-jia; Feng, Gan-sheng

    2008-01-01

    The purpose of this study is to evaluate the usefulness of multislice spiral computed tomography (CT) in the diagnosis of congenital inner ear malformations. Forty-four patients with sensorineural hearing loss were examined on a Somatom Sensation 16 (Siemens) CT scanner. The 3-dimensional reconstructions and multiplanar reformation (MPR) were performed using the volume-rendering technique (VRT) on the workstation. Of the 44 patients examined for this study, 25 patients were found to be normal and 19 patients (36 ears) were diagnosed with congenital inner ear malformations. Of the malformations, the axial, MPR, and VRT images can all display the site and degree in 33 of the ears. Volume-rendering technique images were superior to the axial images in displaying the malformations in 3 ears with small lateral semicircular canal malformations. The common malformations were Michel deformity (1 ear), common cavity deformity (3 ears), incomplete partition I (3 ears), incomplete partition II (Mondini deformity) (5 ears), vestibular and semicircular canal malformations (14 ears), enlarged vestibular aqueduct (16 ears, 6 of which had other malformations), and internal auditory canal malformation (8 ears, all accompanied by other malformations). Multislice spiral CT allows a comprehensively assessment of various congenital inner ear malformations through high-quality MPR and VRT reconstructions. Volume-rendering technique images can display the site and degree of the malformation 3-dimensionally and intuitionisticly. This is very useful to the cochlear implantation.

  8. A grid-based tropospheric product for China using a GNSS network

    Science.gov (United States)

    Zhang, Hongxing; Yuan, Yunbin; Li, Wei; Zhang, Baocheng; Ou, Jikun

    2017-11-01

    Tropospheric delay accounts for one source of error in global navigation satellite systems (GNSS). To better characterize the tropospheric delays in the temporal and spatial domain and facilitate the safety-critical use of GNSS across China, a method is proposed to generate a grid-based tropospheric product (GTP) using the GNSS network with an empirical tropospheric model, known as IGGtrop. The prototype system generates the GTPs in post-processing and real-time modes and is based on the undifferenced and uncombined precise point positioning (UU-PPP) technique. GTPs are constructed for a grid form (2.0{°}× 2.5{°} latitude-longitude) over China with a time resolution of 5 min. The real-time GTP messages are encoded in a self-defined RTCM3 format and broadcast to users using NTRIP (networked transport of RTCM via internet protocol), which enables efficient and safe transmission to real-time users. Our approach for GTP generation consists of three sequential steps. In the first step, GNSS-derived zenith tropospheric delays (ZTDs) for a network of GNSS stations are estimated using UU-PPP. In the second step, vertical adjustments for the GNSS-derived ZTDs are applied to address the height differences between the GNSS stations and grid points. The ZTD height corrections are provided by the IGGtrop model. Finally, an inverse distance weighting method is used to interpolate the GNSS-derived ZTDs from the surrounding GNSS stations to the location of the grid point. A total of 210 global positioning system (GPS) stations from the crustal movement observation network of China are used to generate the GTPs in both post-processing and real-time modes. The accuracies of the GTPs are assessed against with ERA-Interim-derived ZTDs and the GPS-derived ZTDs at 12 test GPS stations, respectively. The results show that the post-processing and real-time GTPs can provide the ZTDs with accuracies of 1.4 and 1.8 cm, respectively. We also apply the GTPs in real-time kinematic GPS PPP

  9. The contribution of Multi-GNSS Experiment (MGEX) to precise point positioning

    Science.gov (United States)

    Guo, Fei; Li, Xingxing; Zhang, Xiaohong; Wang, Jinling

    2017-06-01

    In response to the changing world of GNSS, the International GNSS Service (IGS) has initiated the Multi-GNSS Experiment (MGEX). As part of the MGEX project, initial precise orbit and clock products have been released for public use, which are the key prerequisites for multi-GNSS precise point positioning (PPP). In particular, precise orbits and clocks at intervals of 5 min and 30 s are presently available for the new emerging systems. This paper investigates the benefits of multi-GNSS for PPP. Firstly, orbit and clock consistency tests (between different providers) were performed for GPS, GLONASS, Galileo and BeiDou. In general, the differences of GPS are, respectively, 1.0-1.5 cm for orbit and 0.1 ns for clock. The consistency of GLONASS is worse than GPS by a factor of 2-3, i.e. 2-4 cm for orbit and 0.2 ns for clock. However, the corresponding differences of Galileo and BeiDou are significantly larger than those of GPS and GLONASS, particularly for the BeiDou GEO satellites. Galileo as well as BeiDou IGSO/MEO products have a consistency of 0.1-0.2 m for orbit, and 0.2-0.3 ns for clock. As to BeiDou GEO satellites, the difference of their orbits reaches 3-4 m in along-track, 0.5-0.6 m in cross-track, and 0.2-0.3 m in the radial directions, together with an average RMS of 0.6 ns for clock. Furthermore, the short-term stability of multi-GNSS clocks was analyzed by Allan deviation. Results show that clock stability of the onboard GNSS is highly dependent on the satellites generations, operational lifetime, orbit types, and frequency standards. Finally, kinematic PPP tests were conducted to investigate the contribution of multi-GNSS and higher rate clock corrections. As expected, the positioning accuracy as well as convergence speed benefit from the fusion of multi-GNSS and higher rate of precise clock corrections. The multi-GNSS PPP improves the positioning accuracy by 10-20%, 40-60%, and 60-80% relative to the GPS-, GLONASS-, and BeiDou-only PPP. The usage of 30 s

  10. Monitoring water cycle elements using GNSS geodetic receivers at the field research station Marquardt, Germany

    Science.gov (United States)

    Simeonov, Tzvetan; Vey, Sibylle; Alshawaf, Fadwa; Dick, Galina; Guerova, Guergana; Güntner, Andreas; Hohmann, Christian; Kunwar, Ajeet; Trost, Benjamin; Wickert, Jens

    2017-04-01

    Water storage variations in the atmosphere and in soils are among the most dynamic within the Earth's water cycle. The continuous measurement of water storage in these media with a high spatial and temporal resolution is a challenging task, not yet completely solved by various observation techniques. With the development of the Global Navigation Satellite Systems (GNSS) a new approach for atmospheric water vapor estimation in the atmosphere and in parallel of soil moisture in the vicinity of GNSS ground stations was established in the recent years with several key advantages compared to traditional techniques. Regional and global GNSS networks are nowadays operationally used to provide the Integrated Water Vapor (IWV) information with high temporal resolution above the individual stations. Corresponding data products are used to improve the day-by-day weather prediction of leading forecast centers. Selected stations from these networks can be used to additionally derive the soil moisture in the vicinity of the receivers. Such parallel measurement of IWV and soil moisture using a single measuring device provides a unique possibility to analyze water fluxes between the atmosphere and the land surface. We installed an advanced experimental GNSS setup for hydrology at the field research station of the Leibniz Institute for Agricultural Engineering and Bioeconomy in Marquardt, around 30km West of Berlin, Germany. The setup includes several GNSS receivers, various Time Domain Reflectometry (TDR) sensors at different depths for soil moisture measurement and an meteorological station. The setup was mainly installed to develop and improve GNSS based techniques for soil moisture determination and to analyze GNSS IWV and SM in parallel on a long-term perspective. We introduce initial results from more than two years of measurements. The comparison in station Marquardt shows good agreement (correlation 0.79) between the GNSS derived soil moisture and the TDR measurements. A

  11. Enhanced UHF RFID tags for drug tracing.

    Science.gov (United States)

    Catarinucci, Luca; Colella, Riccardo; De Blasi, Mario; Patrono, Luigi; Tarricone, Luciano

    2012-12-01

    Radio Frequency Identification (RFID) technology is playing a crucial role for item-level tracing systems in healthcare scenarios. The pharmaceutical supply chain is a fascinating application context, where RFID can guarantee transparency in the drug flow, supporting both suppliers and consumers against the growing counterfeiting problem. In such a context, the choice of the most adequate RFID tag, in terms of shape, frequency, size and reading range, is crucial. The potential presence of items containing materials hostile to the electromagnetic propagation exasperates the problem. In addition, the peculiarities of the different RFID-based checkpoints make even more stringent the requirements for the tag. In this work, the performance of several commercial UHF RFID tags in each step of the pharmaceutical supply chain has been evaluated, confirming the expected criticality. On such basis, a guideline for the electromagnetic design of new high-performance tags capable to overcome such criticalities has been defined. Finally, driven by such guidelines, a new enhanced tag has been designed, realized and tested. Due to patent pending issues, the antenna shape is not shown. Nevertheless, the optimal obtained results do not lose their validity. Indeed, on the one hand they demonstrate that high performance item level tracing systems can actually be implemented also in critical operating conditions. On the other hand, they encourage the tag designer to follow the identified guidelines so to realize enhanced UHF tags.

  12. DICOM involving XML path-tag

    Science.gov (United States)

    Zeng, Qiang; Yao, Zhihong; Liu, Lei

    2011-03-01

    Digital Imaging and Communications in Medicine (DICOM) is a standard for handling, storing, printing, and transmitting information in medical imaging. XML (Extensible Markup Language) is a set of rules for encoding documents in machine-readable form which has become more and more popular. The combination of these two is very necessary and promising. Using XML tags instead of numeric labels in DICOM files will effectively increase the readability and enhance the clear hierarchical structure of DICOM files. However, due to the fact that the XML tags rely heavily on the orders of the tags, the strong data dependency has a lot of influence on the flexibility of inserting and exchanging data. In order to improve the extensibility and sharing of DICOM files, this paper introduces XML Path-Tag to DICOM. When a DICOM file is converted to XML format, adding simple Path-Tag into the DICOM file in place of complex tags will keep the flexibility of a DICOM file while inserting data elements and give full play to the advantages of the structure and readability of an XML file. Our method can solve the weak readability problem of DICOM files and the tedious work of inserting data into an XML file. In addition, we set up a conversion engine that can transform among traditional DICOM files, XML-DCM and XML-DCM files involving XML Path-Tag efficiently.

  13. Communication methods, systems, apparatus, and devices involving RF tag registration

    Science.gov (United States)

    Burghard, Brion J [W. Richland, WA; Skorpik, James R [Kennewick, WA

    2008-04-22

    One technique of the present invention includes a number of Radio Frequency (RF) tags that each have a different identifier. Information is broadcast to the tags from an RF tag interrogator. This information corresponds to a maximum quantity of tag response time slots that are available. This maximum quantity may be less than the total number of tags. The tags each select one of the time slots as a function of the information and a random number provided by each respective tag. The different identifiers are transmitted to the interrogator from at least a subset of the RF tags.

  14. W/Top/Higgs-tagging in ATLAS

    CERN Document Server

    Norjoharuddeen, Nurfikri; The ATLAS collaboration

    2017-01-01

    We present updates of W, Top and Higgs tagging studies with the ATLAS detector. The performance of 2 variable taggers, HEPTopTagger and shower deconstruction are compared in Monte Carlo simulations. To asses the modelling of the taggers’ performance, the tagging efficiencies are measured, with the full 2015+2016 dataset, in semi-leptonic top quark pair events and the background rejections are measured in dijet and photon+jet topologies. Recent developments in subjet reconstruction techniques for high transverse momentum Higgs->bb tagging are also presented.

  15. Tagging Water Sources in Atmospheric Models

    Science.gov (United States)

    Bosilovich, M.

    2003-01-01

    Tagging of water sources in atmospheric models allows for quantitative diagnostics of how water is transported from its source region to its sink region. In this presentation, we review how this methodology is applied to global atmospheric models. We will present several applications of the methodology. In one example, the regional sources of water for the North American Monsoon system are evaluated by tagging the surface evaporation. In another example, the tagged water is used to quantify the global water cycling rate and residence time. We will also discuss the need for more research and the importance of these diagnostics in water cycle studies.

  16. Ear tube surgery - what to ask your doctor

    Science.gov (United States)

    What to ask your doctor about ear tube surgery; Tympanostomy - what to ask your doctor; Myringotomy - what ... other treatments? What are the risks of the surgery? Is it safe to wait before getting ear ...

  17. Body lift, drag and power are relatively higher in large-eared than in small-eared bat species.

    Science.gov (United States)

    Håkansson, Jonas; Jakobsen, Lasse; Hedenström, Anders; Johansson, L Christoffer

    2017-10-01

    Bats navigate the dark using echolocation. Echolocation is enhanced by external ears, but external ears increase the projected frontal area and reduce the streamlining of the animal. External ears are thus expected to compromise flight efficiency, but research suggests that very large ears may mitigate the cost by producing aerodynamic lift. Here we compare quantitative aerodynamic measures of flight efficiency of two bat species, one large-eared ( Plecotus auritus ) and one small-eared ( Glossophaga soricina ), flying freely in a wind tunnel. We find that the body drag of both species is higher than previously assumed and that the large-eared species has a higher body drag coefficient, but also produces relatively more ear/body lift than the small-eared species, in line with prior studies on model bats. The measured aerodynamic power of P. auritus was higher than predicted from the aerodynamic model, while the small-eared species aligned with predictions. The relatively higher power of the large-eared species results in lower optimal flight speeds and our findings support the notion of a trade-off between the acoustic benefits of large external ears and aerodynamic performance. The result of this trade-off would be the eco-morphological correlation in bat flight, with large-eared bats generally adopting slow-flight feeding strategies. © 2017 The Author(s).

  18. Getting Teens to Read with Their Ears

    Science.gov (United States)

    Fues, Marianne Cole

    2009-01-01

    Audiobooks have been around for years in various formats, like cassette tapes and CDs. This article describes a new type of audiobook on the market which is generating an interest in "reading." The device, called Playaway, is the size of a MP3 player and comes with a lanyard and ear buds. Buttons on the back of the player control the…

  19. "Hot Tub Rash" and "Swimmer's Ear" (Pseudomonas)

    Science.gov (United States)

    Facts About “Hot Tub Rash” and “Swimmer’s Ear” (Pseudomonas) What is Pseudomonas and how can it affect me? Pseudomonas (sue-doh- ... a major cause of infections commonly known as “hot tub rash” and “swimmer’s ear.” This germ is ...

  20. The inner ear produces a natriuretic hormone

    DEFF Research Database (Denmark)

    Qvortrup, K; Rostgaard, J; Holstein-Rathlou, N H

    1996-01-01

    Cytoplasmic granules have been demonstrated in epithelial cells from the endolymphatic sac, an extraosseus part of the inner ear located in the posterior cranial fossa. Intravenously infused extracts from endolymphatic sacs in anesthetized rats elicited a potent natriuresis and diuresis without e...

  1. DNA isolation from rat tail or ear

    NARCIS (Netherlands)

    Cuppen, E.

    2010-01-01

    This protocol describes a rapid procedure for isolating DNA from rat tail or ear punches. The simplest version of the protocol can be scaled for use in 96-well (deep-well) plates. The quality of the DNA is sufficient for any polymerase chain reaction (PCR)-based genotyping approach.

  2. Infrared tympanic temperature and ear canal morphology

    NARCIS (Netherlands)

    Daanen, H.A.M.

    2006-01-01

    Several publications indicate that the infrared tympanic temperature (IRTT) underestimates the core temperature of the body when the ear canal is long, curvy and narrow. In order to quantify these observations, a study was performed in 10 subjects. The IRTT was determined and compared to the

  3. Mechanics of the exceptional anuran ear

    NARCIS (Netherlands)

    Schoffelen, Richard L. M.; Segenhout, Johannes M.; van Dijk, Pim

    The anuran ear is frequently used for studying fundamental properties of vertebrate auditory systems. This is due to its unique anatomical features, most prominently the lack of a basilar membrane and the presence of two dedicated acoustic end organs, the basilar papilla and the amphibian papilla.

  4. Clinical review of inner ear malformation

    International Nuclear Information System (INIS)

    Kokai, Hiromi; Oohashi, Masami; Ishikawa, Kazuo; Harada, Kouji; Hiratsuka, Hitoshi; Ogasawara, Makoto; Miyashita, Souji; Terayama, Yoshihiko

    2003-01-01

    We had 126 patients with inner ear malformation diagnosed with temporal bone computed tomography (CT) scans at Azabu Triology Hospital between 1996 and 2002. We classified cases of inner ear malformation according to Jackler et al. The incidence of inner ear malformation in our series was as follows; labyrinthine anomalies 61% (isolated lateral semicircular canal dysplasia 56%, compound semicircular canal dysplasia 4%, semicircular canal aplasia 1%), cochlear anomalies 24%, enlargement of the vestibular aqueduct 12%, narrow internal auditory canal 2%, complete labyrinthine aplasia 1%, enlargement of the cochlear aqueduct 0%. The most frequent anomaly was isolated lateral semicircular canal dysplasia. We did not detect any significant clinical features in this anomaly. There were 2 patients with cochlear anomalies who had past histories of meningitis. Some patients with enlargement of the vestibular aqueduct had frequent attacks of fluctuating hearing. Clinically it is important to detect patients with inner ear malformation such as cochlear anomalies and enlargement of the vestibular aqueduct usually accompanied by congenital sensorineural hearing loss. For patients with congenital sensorineural hearing loss, we recommend temporal bone CT scan. (author)

  5. The first neutron beam hits EAR2

    CERN Multimedia

    Antonella Del Rosso

    2014-01-01

    On 25 July 2014, about a year after construction work began, the Experimental Area 2 (EAR2) of CERN’s neutron facility n_TOF recorded its first beam. Unique in many aspects, EAR2 will start its rich programme of experimental physics this autumn.   The last part of the EAR2 beamline: the neutrons come from the underground target and reach the top of the beamline, where they hit the samples. Built about 20 metres above the neutron production target, EAR2 is in fact a bunker connected to the n_TOF underground facilities via a duct 80 cm in diameter, where the beamline is installed. The feet of the bunker support pillars are located on the concrete structure of the n_TOF tunnel and part of the structure lies above the old ISR building. A beam dump located on the roof of the building completes the structure. Neutrons are used by physicists to study neutron-induced reactions with applications in a number of fields, including nuclear waste transmutation, nuclear technology, nuclear astrop...

  6. Evolution: Fossil Ears and Underwater Sonar.

    Science.gov (United States)

    Lambert, Olivier

    2016-08-22

    A key innovation in the history of whales was the evolution of a sonar system together with high-frequency hearing. Fossils of an archaic toothed whale's inner ear bones provide clues for a stepwise emergence of underwater echolocation ability. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. THE DISCHARGING EAR: A PRACTICAL APPROACH

    African Journals Online (AJOL)

    Enrique

    brospinal fluid (CSF) and saliva. Wax is the normal secretion of the glands of the external ear canal, and patients .... acidic pH. They are effective against. P. aeruginosa, S. aureus, Proteus spp. and Candida. The aminoglycosides, polymyxin B, chloramphenicol and acetic acid are potentially ototoxic, the greatest risk of.

  8. Headaches from ear, nose and throat diseases

    International Nuclear Information System (INIS)

    Reck, R.

    1984-01-01

    Headaches are a frequent symptom in ENT-patients. The complex sensory innervation of the ear, nose and paranasal sinuses is demonstrated. Heterotopic or referred pain must be differentiated from homotopic pain that is experienced at the point of injury. The nervous pathways of heterotopic otalgia are shown. The quality of pain of the most common rhinological and otological diseases is reported. (orig.) [de

  9. Collapse of the ear canal during masking for bone conduction.

    Science.gov (United States)

    Sauer, R C; Ford, C N

    1986-01-01

    Although it is well recognized that collapse of the external meatus can mimic a conductive hearing loss in the test ear, attention must also be directed to the masked ear during masked bone conduction threshold testing. Failure to recognize collapse of the masked ear may result in a false air-bone gap in the test ear. Two such cases are presented and the mechanism analyzed. Suggestions as to identification and resolution of this problem are discussed.

  10. Evaluation of the incidence of bacteremia following middle ear operations

    OpenAIRE

    Mohammad Naeimi; Kiarash Ghazvini K; Mohammad Taghi Shakeri MT; Merangiz Kaboli; Mahmood Bagheri

    2009-01-01

    Introduction: Bacteremia following middle ear surgeries occurs in a significant number of patients. The aim of this study is to investigate the incidence of bacteremia following middle ear surgeries. Materials and Methods: Sixty two patients who where candidates for middle ear operation were enrolled in this study. Blood samples were obtained from each patient immediately before and after operation for bacteriologic analysis. Demographic and middle ear disease characteristics were also record...

  11. Rapid kinematic finite source inversion for Tsunamic Early Warning using high rate GNSS data

    Science.gov (United States)

    Chen, K.; Liu, Z.; Song, Y. T.

    2017-12-01

    Recently, Global Navigation Satellite System (GNSS) has been used for rapid earthquake source inversion towards tsunami early warning. In practice, two approaches, i.e., static finite source inversion based on permanent co-seismic offsets and kinematic finite source inversion using high-rate (>= 1 Hz) co-seismic displacement waveforms, are often employed to fulfill the task. The static inversion is relatively easy to be implemented and does not require additional constraints on rupture velocity, duration, and temporal variation. However, since most GNSS receivers are deployed onshore locating on one side of the subduction fault, there is very limited resolution on near-trench fault slip using GNSS in static finite source inversion. On the other hand, the high-rate GNSS displacement waveforms, which contain the timing information of earthquake rupture explicitly and static offsets implicitly, have the potential to improve near-trench resolution by reconciling with the depth-dependent megathrust rupture behaviors. In this contribution, we assess the performance of rapid kinematic finite source inversion using high-rate GNSS by three selected historical tsunamigenic cases: the 2010 Mentawai, 2011 Tohoku and 2015 Illapel events. With respect to the 2010 Mentawai case, it is a typical tsunami earthquake with most slip concentrating near the trench. The static inversion has little resolution there and incorrectly puts slip at greater depth (>10km). In contrast, the recorded GNSS displacement waveforms are deficit in high-frequency energy, the kinematic source inversion recovers a shallow slip patch (depth less than 6 km) and tsunami runups are predicted quite reasonably. For the other two events, slip from kinematic and static inversion show similar characteristics and comparable tsunami scenarios, which may be related to dense GNSS network and behavior of the rupture. Acknowledging the complexity of kinematic source inversion in real-time, we adopt the back

  12. GNSS-based operational monitoring devices for forest logging operation chains

    Directory of Open Access Journals (Sweden)

    Raimondo Gallo

    2013-09-01

    Full Text Available The first results of a new approach for implementing operational monitoring tool to control the performance of forest mechanisation chains are proposed and discussed. The solution is based on Global Navigation Satellite System (GNSS tools that are the core of a datalogging system that, in combination with a specific inference-engine, is able to analyse process times, work distances, forward speeds, vehicle tracking and number of working cycles in forest operations. As a consequence the operational monitoring control methods could provide an evaluation of the efficiency of the investigated forest operations. The study has monitored the performance of a tower yarder with crane and processor-head, during logging operations. The field surveys consisted on the installation of the GNSS device directly on the forest equipment for monitoring its movements. Simultaneously the field survey considered the integration of the GNSS information with a time study of work elements based on the continuous time methods supported by a time study board. Additionally, where possible, the onboard computer of the forest machine was also used in order to obtain additional information to be integrated to the GNSS data and the time study. All the recorded GNSS data integrated with the work elements study were thus post-processed through GIS analysis. The preliminary overview about the application of this approach on harvesting operations has permitted to assess a good feasibility of the use of GNSS in the relief of operative times in high mechanised forest chains. Results showed an easy and complete identification of the different operative cycles and elementary operations phases, with a maximum difference between the two methodologies of 10.32%. The use of GNSS installed on forest equipment, integrated with the inferenceengine and also with an interface for data communication or data storage, will permit an automatic or semi-automatic operational monitoring, improving

  13. Utilizing GNSS Reflectometry to Assess Surface Inundation Dynamics in Tropical Wetlands

    Science.gov (United States)

    Jensen, K.; McDonald, K. C.; Podest, E.; Chew, C. C.

    2017-12-01

    Tropical wetlands play a significant role in global atmospheric methane and terrestrial water storage. Despite the growing number of remote sensing products from satellite sensors, both spatial distribution and temporal variability of wetlands remain highly uncertain. An emerging innovative approach to mapping wetlands is offered by GNSS reflectometry (GNSS-R), a bistatic radar concept that takes advantage of GNSS transmitting satellites to yield observations with global coverage and rapid revisit time. This technology offers the potential to capture dynamic inundation changes in wetlands at higher temporal fidelity and sensitivity under the canopy than presently possible. We present an integrative analysis of radiometric modeling, ground measurements, and several microwave remote sensing datasets traditionally used for wetland observations. From a theoretical standpoint, GNSS-R sensitivities for vegetation and wetlands are investigated with a bistatic radar model in order to understand the interactions of the signal with various land surface components. GNSS reflections from the TechDemoSat-1 (TDS-1), Soil Moisture Active Passive (SMAP), and Cyclone GNSS (CYGNSS) missions are tested experimentally with contemporaneous (1) field measurements collected from the Pacaya Samiria National Reserve in the Peruvian Amazon, (2) imaging radar from Sentinel-1 and PALSAR-2 observed over a variety of tropical wetland systems, and (3) pan-tropical coarse-resolution (25km) microwave datasets (Surface Water Microwave Product Series). We find that GNSS-R data provide the potential to extend capabilities of current remote sensing techniques to characterize surface inundation extent, and we explore how to maximize synergism between different satellite sensors to produce an enhanced wetland monitoring product.

  14. GNSS Derived Ionospheric TEC Observed Through Different TEC Calibration Techniques in the Brazilian Sector

    Science.gov (United States)

    Becker-Guedes, F.; Carmo, C. S.; Camargo, P. O.; Monico, J. F. G.; Nicoli Candido, C. M.

    2017-12-01

    Global Navigation Satellite System (GNSS) is becoming a reliable tool for use in air navigation systems. Its use as the main technology for determination of airplanes positioning has various economic and logistic benefits but it depends strongly on the ionospheric layer influences. The Brazilian sector ionosphere, mainly over the equatorial ionization anomaly (EIA), presents remarkable errors in the GNSS signal as compared to North America and Europe. In order to study the total electron content latitudinal variation of the Brazilian ionosphere we used a pair of GNSS receivers on the ground, one located in the equatorial region (Sao Luis) and other in the southern crest of the EIA (Cachoeira Paulista), to collect the GNSS observables and calculate the vertical TEC using different methods that has proven to work well to describe the ionospheric behavior in the North America and in Europe. We compared this results with a modified Nagoya TEC calculation method used by the EMBRACE (Estudo e Monitoramento BRAsileiro do Clima Espacial - Brazilian Study and Monitoring of Space Weather) program. This work intends to follow the performance of different TEC tuning methods to evaluate the spurious effects of the ionospheric EIA gradients in the TEC determination under typical conditions of the low-latitudes ionosphere in the Brazilian sector. The calculated TEC under different solar cycle conditions, geomagnetic activity, and seasonal variations show deviations in the performance of each method and stress the importance of well adjust the GNSS observations to local conditions in order to optimize the TEC evaluation. This study contributes to a better understanding of local GNSS signal errors in the global intent of offering conditions to improve the accuracy, integrity, availability, and continuity requirements for the use of GNSS for air navigation in South America.

  15. [European Portuguese EARS test battery adaptation].

    Science.gov (United States)

    Alves, Marisa; Ramos, Daniela; Oliveira, Graça; Alves, Helena; Anderson, Ilona; Magalhães, Isabel; Martins, Jorge H; Simões, Margarida; Ferreira, Raquel; Fonseca, Rita; Andrade, Susana; Silva, Luís; Ribeiro, Carlos; Ferreira, Pedro Lopes

    2014-01-01

    The use of adequate assessment tools in health care is crucial for the management of care. The lack of specific tools in Portugal for assessing the performance of children who use cochlear implants motivated the translation and adaptation of the EARS (Evaluation of Auditory Responses to Speech) test battery into European Portuguese. This test battery is today one of the most commonly used by (re)habilitation teams of deaf children who use cochlear implants worldwide. The goal to be achieved with the validation of EARS was to provide (re)habilitation teams an instrument that enables: (i) monitoring the progress of individual (re)habilitation, (ii) managing a (re)habilitation program according to objective results, comparable between different (re)habilitation teams, (iii) obtaining data that can be compared with the results of international teams, and (iv) improving engagement and motivation of the family and other professionals from local teams. For the test battery translation and adaptation process, the adopted procedures were the following: (i) translation of the English version into European Portuguese by a professional translator, (ii) revision of the translation performed by an expert panel, including doctors, speech-language pathologists and audiologists, (iii) adaptation of the test stimuli by the team's speechlanguage pathologist, and (iv) further review by the expert panel. For each of the tests that belong to the EARS battery, the introduced adaptations and adjustments are presented, combining the characteristics and objectives of the original tests with the linguistic and cultural specificities of the Portuguese population. The difficulties that have been encountered during the translation and adaptation process and the adopted solutions are discussed. Comparisons are made with other versions of the EARS battery. We defend that the translation and the adaptation process followed for the EARS test battery into European Portuguese was correctly conducted

  16. Comparative Performance of Acoustic-tagged and PIT-tagged Juvenile Salmonids

    Energy Technology Data Exchange (ETDEWEB)

    Hockersmith, Eric E.; Brown, Richard S.; Liedtke, Theresa L.

    2008-02-01

    Numerous research tools and technologies are currently being used to evaluate fish passage and survival to determine the impacts of the Federal Columbia River Power System (FCRPS) on endangered and threatened juvenile salmonids, including PIT tags, balloon tags, hydroacoustic evaluations, radio telemetry, and acoustic telemetry. Each has advantages and disadvantages, but options are restricted in some situations because of limited capabilities of a specific technology, lack of detection capability downstream, or availability of adequate numbers of fish. However, there remains concern about the comparative effects of the tag or the tagging procedure on fish performance. The recently developed Juvenile Salmonid Acoustic Telemetry System (JSATS) acoustic transmitter is the smallest active acoustic tag currently available. The goal of this study was to determine whether fish tagged with the JSATS acoustic-telemetry tag can provide unbiased estimates of passage behavior and survival within the performance life of the tag. We conducted both field and laboratory studies to assess tag effects. For the field evaluation we released a total of 996 acoustic-tagged fish in conjunction with 21,026 PIT-tagged fish into the tailrace of Lower Granite Dam on 6 and 13 May. Travel times between release and downstream dams were not significantly different for the majority of the reaches between acoustic-tagged and PIT-tagged fish. In addition to the field evaluation, a series of laboratory experiments were conducted to determine if growth and survival of juvenile Chinook salmon surgically implanted with acoustic transmitters is different than untagged or PIT tagged juvenile Chinook salmon. Only yearling fish with integrated and non-integrated transmitters experienced mortalities, and these were low (<4.5%). Mortality among sub-yearling control and PIT-tag treatments ranged up to 7.7% while integrated and non-integrated treatments had slightly higher rates (up to 8.3% and 7

  17. Ear asymmetries in middle-ear, cochlear, and brainstem responses in human infants

    OpenAIRE

    Keefe, Douglas H.; Gorga, Michael P.; Jesteadt, Walt; Smith, Lynette M.

    2008-01-01

    In 2004, Sininger and Cone-Wesson examined asymmetries in the signal-to-noise ratio (SNR) of otoacoustic emissions (OAE) in infants, reporting that distortion-product (DP)OAE SNR was larger in the left ear, whereas transient-evoked (TE)OAE SNR was larger in the right. They proposed that cochlear and brainstem asymmetries facilitate development of brain-hemispheric specialization for sound processing. Similarly, in 2006 Sininger and Cone-Wesson described ear asymmetries mainly favoring the rig...

  18. A comparison of methods to estimate vertical land motion trends from GNSS and altimetry at tide gauge stations

    Science.gov (United States)

    Kleinherenbrink, Marcel; Riva, Riccardo; Frederikse, Thomas

    2018-03-01

    Tide gauge (TG) records are affected by vertical land motion (VLM), causing them to observe relative instead of geocentric sea level. VLM can be estimated from global navigation satellite system (GNSS) time series, but only a few TGs are equipped with a GNSS receiver. Hence, (multiple) neighboring GNSS stations can be used to estimate VLM at the TG. This study compares eight approaches to estimate VLM trends at 570 TG stations using GNSS by taking into account all GNSS trends with an uncertainty smaller than 1 mm yr-1 within 50 km. The range between the methods is comparable with the formal uncertainties of the GNSS trends. Taking the median of the surrounding GNSS trends shows the best agreement with differenced altimetry-tide gauge (ALT-TG) trends. An attempt is also made to improve VLM trends from ALT-TG time series. Only using highly correlated along-track altimetry and TG time series reduces the SD of ALT-TG time series by up to 10 %. As a result, there are spatially coherent changes in the trends, but the reduction in the root mean square (RMS) of differences between ALT-TG and GNSS trends is insignificant. However, setting correlation thresholds also acts like a filter to remove problematic TG time series. This results in sets of ALT-TG VLM trends at 344-663 TG locations, depending on the correlation threshold. Compared to other studies, we decrease the RMS of differences between GNSS and ALT-TG trends (from 1.47 to 1.22 mm yr-1), while we increase the number of locations (from 109 to 155), Depending on the methods the mean of differences between ALT-TG and GNSS trends vary between 0.1 and 0.2 mm yr-1. We reduce the mean of the differences by taking into account the effect of elastic deformation due to present-day mass redistribution. At varying ALT-TG correlation thresholds, we provide new sets of trends for 759 to 939 different TG stations. If both GNSS and ALT-TG trend estimates are available, we recommend using the GNSS trend estimates because residual

  19. Review of the state of the art and future prospects of the ground-based GNSS meteorology in Europe

    Directory of Open Access Journals (Sweden)

    G. Guerova

    2016-11-01

    Full Text Available Global navigation satellite systems (GNSSs have revolutionised positioning, navigation, and timing, becoming a common part of our everyday life. Aside from these well-known civilian and commercial applications, GNSS is now an established atmospheric observing system, which can accurately sense water vapour, the most abundant greenhouse gas, accounting for 60–70 % of atmospheric warming. In Europe, the application of GNSS in meteorology started roughly two decades ago, and today it is a well-established field in both research and operation. This review covers the state of the art in GNSS meteorology in Europe. The advances in GNSS processing for derivation of tropospheric products, application of GNSS tropospheric products in operational weather prediction and application of GNSS tropospheric products for climate monitoring are discussed. The GNSS processing techniques and tropospheric products are reviewed. A summary of the use of the products for validation and impact studies with operational numerical weather prediction (NWP models as well as very short weather prediction (nowcasting case studies is given. Climate research with GNSSs is an emerging field of research, but the studies so far have been limited to comparison with climate models and derivation of trends. More than 15 years of GNSS meteorology in Europe has already achieved outstanding cooperation between the atmospheric and geodetic communities. It is now feasible to develop next-generation GNSS tropospheric products and applications that can enhance the quality of weather forecasts and climate monitoring. This work is carried out within COST Action ES1206 advanced global navigation satellite systems tropospheric products for monitoring severe weather events and climate (GNSS4SWEC, http://gnss4swec.knmi.nl.

  20. Acoustic impedances of ear canals measured by impedance tube

    DEFF Research Database (Denmark)

    Ciric, Dejan; Hammershøi, Dorte

    2007-01-01

    During hearing sensitivity tests, the sound field is commonly generated by an earphone placed on a subject ear. One of the factors that can affect the sound transmission in the ear is the acoustic impedance of the ear canal. Its importance is related to the contribution of other elements involved...

  1. Bacteriology of chronic discharging ears in Port Harcourt, Nigeria ...

    African Journals Online (AJOL)

    Methods: Ear swabs of discharging ears aseptically collected from 102 patients of various age groups attending Ear, Nose, and Throat out-patient clinic at University of Port Harcourt Teaching Hospital were cultured for bacterial agents using blood agar, chocolate agar and MacConkey agar. Culture plates were incubated ...

  2. Inner ear malformations in siblings presenting with vestibular ...

    African Journals Online (AJOL)

    Although the association between inner ear abnormalities and progressive sensorineural hearing loss is well known, vestibular signs or loss of vestibular function in these ... We provide a brief overview of the latest classification of these inner ear defects as well as a review of the literature pertaining to children with inner ear ...

  3. Impact of Jacobson's (tympanic) nerve sectioning on middle ear functions.

    Science.gov (United States)

    Ceylan, Alper; Göksu, Nebil; Kemaloğlu, Yusuf Kemal; Uğur, Birol; Akyürek, Nalan; Bayazit, Yildirim A

    2007-04-01

    The purpose of this study was to evaluate the influence of sectioning of the Jacobson's (tympanic) nerve on middle ear functions. Twenty-five adult New Zealand rabbits were included in this study. The Jacobson's nerve was cut in the left ear of the rabbits (study group), whereas only a small mucosal incision was performed while keeping the Jacobson's nerve intact in their right ear (control group). After the operation, the ears were assessed both otomicroscopically and histopathologically on Days 30, 60, and 90. On otomicroscopy, retraction pockets were observed in 48 and 4% of the ears in the study and control groups, respectively (p ear effusion was observed in 56 and 12%, respectively (p ear mucosa was present in all ears in the study group, whereas it was present only in 20% of the control ears (p ear chemosensory organs and are involved in the regulation of middle ear aeration. Disruption of these neural elements such as Jacobson's nerve negatively impacts on middle ear functions and may result in atelectasis.

  4. Comparing the hierarchy of author given tags and repository given tags in a large document archive

    Science.gov (United States)

    Tibély, Gergely; Pollner, Péter; Palla, Gergely

    2016-10-01

    Folksonomies - large databases arising from collaborative tagging of items by independent users - are becoming an increasingly important way of categorizing information. In these systems users can tag items with free words, resulting in a tripartite item-tag-user network. Although there are no prescribed relations between tags, the way users think about the different categories presumably has some built in hierarchy, in which more special concepts are descendants of some more general categories. Several applications would benefit from the knowledge of this hierarchy. Here we apply a recent method to check the differences and similarities of hierarchies resulting from tags given by independent individuals and from tags given by a centrally managed repository system. The results from our method showed substantial differences between the lower part of the hierarchies, and in contrast, a relatively high similarity at the top of the hierarchies.

  5. User Interface Program for secure electronic tags

    International Nuclear Information System (INIS)

    Cai, Y.; Koehl, E.R.; Carlson, R.D.; Raptis, A.C.

    1995-05-01

    This report summarizes and documents the efforts of Argonne National Laboratory (ANL) in developing a secure tag communication user interface program comprising a tag monitor and a communication tool. This program can perform the same functions as the software that was developed at the Lawrence Livermore National Laboratory (LLNL), but it is enhanced with a user-friendly screen. It represents the first step in updating the TRANSCOM Tracking System (TRANSCOM) by incorporating a tag communication screen menu into the main menu of the TRANSCOM user program. A working version of TRANSCOM, enhanced with ANL secure-tag graphics, will strongly support the Department of Energy Warhead Dismantlement/Special Nuclear Materials Control initiatives. It will allow commercial satellite tracking of the movements and operational activities of treaty-limited items and transportation vehicles throughout Europe and the former USSR, as well as the continental US

  6. In vitro tagging of embryos with nanoparticles

    OpenAIRE

    Fynewever, Tricia L.; Agcaoili, Evelyn S.; Jacobson, John D.; Patton, William C.; Chan, Philip J.

    2006-01-01

    Purpose: To develop an in vitro method for tagging embryos and to compare the development of the embryos after nanoparticles injection versus externally-applied nanoparticles derived from either polystyrene or polyacrylonitrile.

  7. Flavour Tagging with the LHCb experiment

    CERN Multimedia

    Birnkraut, Alex

    2015-01-01

    Measurements of flavour oscillations and time-dependent CP asymmetries in neutral B meson systems require knowledge of the b quark production flavour. This identification is performed by the Flavour Tagging.

  8. 50 CFR 635.33 - Archival tags.

    Science.gov (United States)

    2010-10-01

    ... landing; furnish all requested information regarding the location and method of capture; and, as... recovery of the tag by a NMFS scientist, enforcement agent, or other person designated in writing by NMFS...

  9. User Interface Program for secure electronic tags

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Y.; Koehl, E.R.; Carlson, R.D.; Raptis, A.C.

    1995-05-01

    This report summarizes and documents the efforts of Argonne National Laboratory (ANL) in developing a secure tag communication user interface program comprising a tag monitor and a communication tool. This program can perform the same functions as the software that was developed at the Lawrence Livermore National Laboratory (LLNL), but it is enhanced with a user-friendly screen. It represents the first step in updating the TRANSCOM Tracking System (TRANSCOM) by incorporating a tag communication screen menu into the main menu of the TRANSCOM user program. A working version of TRANSCOM, enhanced with ANL secure-tag graphics, will strongly support the Department of Energy Warhead Dismantlement/Special Nuclear Materials Control initiatives. It will allow commercial satellite tracking of the movements and operational activities of treaty-limited items and transportation vehicles throughout Europe and the former USSR, as well as the continental US.

  10. b-flavour tagging in pp collisions

    CERN Multimedia

    Birnkraut, Alex

    2015-01-01

    An essential ingredient of all time-dependent CP violation studies of B mesons is the ability to tag the initial flavour of the B meson. The harsh environment of 7 and 8 TeV pp collisions makes this a particularly difficult enterprise. We report progresses in the flavour tagging of B0 and Bs mesons, including developments of novel techniques like the use of an opposite side charm tagger.

  11. W and top tagging scale factors

    CERN Document Server

    CMS Collaboration

    2017-01-01

    This note presents an improved determination of the efficiency and data/MC scale factors for the identification of hadronically decaying top quarks using the full 2016 CMS dataset. Also shown is an improved measurement of the W boson tagging performance using the full 2016 CMS dataset. Finally methods for the extraction of W tagging scale factors at high transverse momentum using fully merged top quarks are shown.

  12. Clone tag detection in distributed RFID systems.

    Science.gov (United States)

    Kamaludin, Hazalila; Mahdin, Hairulnizam; Abawajy, Jemal H

    2018-01-01

    Although Radio Frequency Identification (RFID) is poised to displace barcodes, security vulnerabilities pose serious challenges for global adoption of the RFID technology. Specifically, RFID tags are prone to basic cloning and counterfeiting security attacks. A successful cloning of the RFID tags in many commercial applications can lead to many serious problems such as financial losses, brand damage, safety and health of the public. With many industries such as pharmaceutical and businesses deploying RFID technology with a variety of products, it is important to tackle RFID tag cloning problem and improve the resistance of the RFID systems. To this end, we propose an approach for detecting cloned RFID tags in RFID systems with high detection accuracy and minimal overhead thus overcoming practical challenges in existing approaches. The proposed approach is based on consistency of dual hash collisions and modified count-min sketch vector. We evaluated the proposed approach through extensive experiments and compared it with existing baseline approaches in terms of execution time and detection accuracy under varying RFID tag cloning ratio. The results of the experiments show that the proposed approach outperforms the baseline approaches in cloned RFID tag detection accuracy.

  13. Vector boson tagged jets and jet substructure

    Directory of Open Access Journals (Sweden)

    Vitev Ivan

    2018-01-01

    Full Text Available In these proceedings, we report on recent results related to vector boson-tagged jet production in heavy ion collisions and the related modification of jet substructure, such as jet shapes and jet momentum sharing distributions. Z0-tagging and γ-tagging of jets provides new opportunities to study parton shower formation and propagation in the quark-gluon plasma and has been argued to provide tight constrains on the energy loss of reconstructed jets. We present theoretical predictions for isolated photon-tagged and electroweak boson-tagged jet production in Pb+Pb collisions at √sNN = 5.02 TeV at the LHC, addressing the modification of their transverse momentum and transverse momentum imbalance distributions. Comparison to recent ATLAS and CMS experimental measurements is performed that can shed light on the medium-induced radiative corrections and energy dissipation due to collisional processes of predominantly quark-initiated jets. The modification of parton splitting functions in the QGP further implies that the substructure of jets in heavy ion collisions may differ significantly from the corresponding substructure in proton-proton collisions. Two such observables and the implication of tagging on their evaluation is also discussed.

  14. RATC: A Robust Automated Tag Clustering Technique

    Science.gov (United States)

    Boratto, Ludovico; Carta, Salvatore; Vargiu, Eloisa

    Nowadays, the most dominant and noteworthy web information sources are developed according to the collaborative-web paradigm, also known as Web 2.0. In particular, it represents a novel paradigm in the way users interact with the web. Users (also called prosumers) are no longer passive consumers of published content, but become involved, implicitly and explicitly, as they cooperate by providing their own resources in an “architecture of participation”. In this scenario, collaborative tagging, i.e., the process of classifying shared resources by using keywords, becomes more and more popular. The main problem in such task is related to well-known linguistic phenomena, such as polysemy and synonymy, making effective content retrieval harder. In this paper, an approach that monitors users activity in a tagging system and dynamically quantifies associations among tags is presented. The associations are then used to create tags clusters. Experiments are performed comparing the proposed approach with a state-of-the-art tag clustering technique. Results -given in terms of classical precision and recall- show that the approach is quite effective in the presence of strongly related tags in a cluster.

  15. Clone tag detection in distributed RFID systems

    Science.gov (United States)

    Kamaludin, Hazalila; Mahdin, Hairulnizam

    2018-01-01

    Although Radio Frequency Identification (RFID) is poised to displace barcodes, security vulnerabilities pose serious challenges for global adoption of the RFID technology. Specifically, RFID tags are prone to basic cloning and counterfeiting security attacks. A successful cloning of the RFID tags in many commercial applications can lead to many serious problems such as financial losses, brand damage, safety and health of the public. With many industries such as pharmaceutical and businesses deploying RFID technology with a variety of products, it is important to tackle RFID tag cloning problem and improve the resistance of the RFID systems. To this end, we propose an approach for detecting cloned RFID tags in RFID systems with high detection accuracy and minimal overhead thus overcoming practical challenges in existing approaches. The proposed approach is based on consistency of dual hash collisions and modified count-min sketch vector. We evaluated the proposed approach through extensive experiments and compared it with existing baseline approaches in terms of execution time and detection accuracy under varying RFID tag cloning ratio. The results of the experiments show that the proposed approach outperforms the baseline approaches in cloned RFID tag detection accuracy. PMID:29565982

  16. Smart-tag Based Data Dissemination

    DEFF Research Database (Denmark)

    Bonnet, Philippe; Beaufour, Allan; Leopold, Martin

    2002-01-01

    Monitoring wide, hostile areas requires disseminating data between fixed, disconnected clusters of sensor nodes. It is not always possible to install long-range radios in order to cover the whole area. We propose to leverage the movement of mobile individuals, equipped with smart-tags, to dissemi......-tag based data dissemination. We use simulation to study the characteristics of the model we propose. Finally, we present an implementation based on Bluetooth smart-tags.......Monitoring wide, hostile areas requires disseminating data between fixed, disconnected clusters of sensor nodes. It is not always possible to install long-range radios in order to cover the whole area. We propose to leverage the movement of mobile individuals, equipped with smart......-tags, to disseminate data across disconnected static nodes spread across a wide area. Static nodes and mobile smart-tags exchange data when they are in the vicinity of each other; smart-tags disseminate data as they move around. In this paper, we propose an algorithm for update propagation and a model for smart...

  17. GNSS in real-time: Demonstration experiment at Berlin Airport International

    Science.gov (United States)

    Wickert, Jens; Dick, Galina; Ge, Maorong; Heise, Stefan; Li, XingXing; Ming, Shangguan; Nischan, Thomas; Ramatschi, Markus; Schuh, Harald; Alberding, Jürgen; Weigmann, Uwe

    2013-04-01

    Real-time (RT) applications are in focus of recent GNSS research. International activities related to the RT data collection and distribution, as well as provision of specific RT data products (e.g., satellite orbits and clocks, station coordinates) are coordinated within the Real-Time Project of the International GNSS Service (IGS). Currently IGS provides real-time data from more than 100 globally distributed GNSS ground stations. This number, in parallel with the extension of various additional international real-time networks, is continuously increasing. In parallel to the rapid development of GNSS RT activities also innovative geophysical applications were pioneered by GNSS research groups and institutions, including GFZ. One prominent example is the use of GNSS components in early warning systems. GNSS measurements can be used there for the rapid detection and characterization of deformation fields, related to earthquakes, which induce Tsunamis. Such deformation data cannot be provided by seismometer measurements, but are important for the prediction of the tsunami wave propagation caused by earthquakes. The GNSS real-time group at GFZ is involved in several research projects related to geophysical RT GNSS applications, and also operates one of the RT analysis centers of the IGS. We introduce results of a real-time GNSS demonstration project, which was performed in 2012 at the new Berlin International Airport BER at Schönefeld, south-east of Berlin city center. The main goal of the project was the demonstration of the functionality of a complex RT-PPP server-client solution for dynamic applications which was developed within a joint research project of GFZ and the company Alberding GmbH. Compared to the standard PPP (clock & orbit) this solution uses additional information (ionosphere, uncalibrated phase delays UPD) to increase the positioning accuracy and to reduce the convergence time. The major challenges of the experiment were the stable operation of the

  18. TagSmart: analysis and visualization for yeast mutant fitness data measured by tag microarrays

    Directory of Open Access Journals (Sweden)

    Xie Dan

    2007-04-01

    Full Text Available Abstract Background A nearly complete collection of gene-deletion mutants (96% of annotated open reading frames of the yeast Saccharomyces cerevisiae has been systematically constructed. Tag microarrays are widely used to measure the fitness of each mutant in a mutant mixture. The tag array experiments can have a complex experimental design, such as time course measurements and drug treatment with multiple dosages. Results TagSmart is a web application for analysis and visualization of Saccharomyces cerevisiae mutant fitness data measured by tag microarrays. It implements a robust statistical approach to assess the concentration differences among S. cerevisiae mutant strains. It also provides an interactive environment for data analysis and visualization. TagSmart has the following advantages over previously described analysis procedures: 1 it is user-friendly software rather than merely a description of analytical procedure; 2 It can handle complicated experimental designs, such as multiple time points and treatment with multiple dosages; 3 it has higher sensitivity and specificity; 4 It allows users to mask out "bad" tags in the analysis. Two biological tests were performed to illustrate the performance of TagSmart. First, we generated titration mixtures of mutant strains, in which the relative concentration of each strain was controlled. We used tag microarrays to measure the numbers of tag copies in each titration mixture. The data was analyzed with TagSmart and the result showed high precision and recall. Second, TagSmart was applied to a dataset in which heterozygous deletion strain mixture pools were treated with a new drug, Cincreasin. TagSmart identified 53 mutant strains as sensitive to Cincreasin treatment. We individually tested each identified mutant, and found 52 out of the 53 predicted mutants were indeed sensitive to Cincreasin. Conclusion TagSmart is provided "as is" to analyze tag array data produced by Affymetrix and Agilent

  19. Survival and tag loss in Moapa White River springfish implanted with passive integrated transponder tags

    Science.gov (United States)

    Dixon, Christopher J.; Mesa, Matthew G.

    2011-01-01

    We monitored survival and tag loss among Moapa White River springfish Crenichthys baileyi moapae that were surgically implanted with passive integrated transponder (PIT; 9 × 2 mm) tags. The fish used in the study ranged from 40 to 67 mm in total length and from 1.0 to 6.5 g in mass; the PIT tag: body weight ratios were 1.0–6.1%. Fish were held for 41 d in live cages within a small, warm desert stream. Survival did not differ between untagged control fish (94.5%) and tagged fish (95.6%). Survival did not appear to be influenced by fish size or PIT tag: body weight ratio, but the small number of fish that died precluded a detailed analysis. Tag retention was 100% among the 86 fish that survived over the 41 d. Our results suggest that surgically implanting 9-mm PIT tags into Moapa White River springfish as small as 40 mm is an effective method for marking them because it has minimal impacts on survival and tag retention is high. More work is needed on the effects of PIT tagging on growth and other performance metrics of springfish and other small desert fishes.

  20. Improving Recommendations in Tag-based Systems with Spectral Clustering of Tag Neighbors

    DEFF Research Database (Denmark)

    Pan, Rong; Xu, Guandong; Dolog, Peter

    2012-01-01

    Tag as a useful metadata reflects the collaborative and conceptual features of documents in social collaborative annotation systems. In this paper, we propose a collaborative approach for expanding tag neighbors and investigate the spectral clustering algorithm to filter out noisy tag neighbors...... in order to get appropriate recommendation for users. The preliminary experiments have been conducted on MovieLens dataset to compare our proposed approach with the traditional collaborative filtering recommendation approach and naive tag neighbors expansion approach in terms of precision, and the result...... demonstrates that our approach could considerably improve the performance of recommendations....

  1. EFFECTS OF OCEAN TIDE MODELS ON GNSS-ESTIMATED ZTD AND PWV IN TURKEY

    Directory of Open Access Journals (Sweden)

    G. Gurbuz

    2015-12-01

    Full Text Available Global Navigation Satellite System (GNSS observations can precisely estimate the total zenith tropospheric delay (ZTD and precipitable water vapour (PWV for weather prediction and atmospheric research as a continuous and all-weather technique. However, apart from GNSS technique itself, estimations of ZTD and PWV are subject to effects of geophysical models with large uncertainties, particularly imprecise ocean tide models in Turkey. In this paper, GNSS data from Jan. 1st to Dec. 31st of 2014 are processed at 4 co-located GNSS stations (GISM, DIYB, GANM, and ADAN with radiosonde from Turkish Met-Office along with several nearby IGS stations. The GAMIT/GLOBK software has been used to process GNSS data of 30-second sample using the Vienna Mapping Function and 10° elevation cut-off angle. Also tidal and non-tidal atmospheric pressure loadings (ATML at the observation level are also applied in GAMIT/GLOBK. Several widely used ocean tide models are used to evaluate their effects on GNSS-estimated ZTD and PWV estimation, such as IERS recommended FES2004, NAO99b from a barotropic hydrodynamic model, CSR4.0 obtained from TOPEX/Poseidon altimetry with the model FES94.1 as the reference model and GOT00 which is again long wavelength adjustments of FES94.1 using TOPEX/Poseidon data at 0.5 by 0.5 degree grid. The ZTD and PWV computed from radiosonde profile observations are regarded as reference values for the comparison and validation. In the processing phase, five different strategies are taken without ocean tide model and with four aforementioned ocean tide models, respectively, which are used to evaluate ocean tide models effects on GNSS-estimated ZTD and PWV estimation through comparing with co-located Radiosonde. Results showed that ocean tide models have greatly affected the estimation of the ZTD in centimeter level and thus the precipitable water vapour in millimeter level, respectively at stations near coasts. The ocean tide model FES2004 that is

  2. Inner ear pressure changes following square wave intracranial or ear canal pressure manipulation in the same guinea pig

    NARCIS (Netherlands)

    Thalen, E; Wit, H; Segenhout, H; Albers, F

    Inner ear pressure was measured in scala tympani with a micropipette during square wave pressure manipulation of the intracranial compartment and, subsequently, of the external ear canal (EEC) in the same guinea pig. As expected, the combination of the cochlear aqueduct and the inner ear behaves as

  3. PROPOSTA DE MÉTODO DE REDE GNSS POR PPP E ANÁLISE DE CONFIABILIDADE

    Directory of Open Access Journals (Sweden)

    Carolina Collischonn

    Full Text Available Embora o método de posicionamento GNSS tradicionalmente utilizado em redes geodésicas seja o relativo. O nível de acurácia obtido com o método de Posicionamento por Ponto Preciso (PPP abre uma nova perspectiva. No PPP são utilizados dados de apenas um receptor GNSS e é fundamental o uso de efemérides e correções dos relógios dos satélites, ambas com alta precisão. Neste artigo é apresentada uma metodologia de desenvolvimento de rede utilizando dados GNSS processados pelo método de PPP e a verificação da sua potencialidade em aplicações geodésicas. Os dados utilizados são de estações GNSS pertencentes à RBMC/IBGE. O serviço de processamento de PPP utilizado é o fornecido pelo IBGE. A partir dos resultados foram feitas análises para verificar a aplicabilidade da metodologia descrita em rede com dados GNSS de 24, 6 e 4 horas de rastreio. Após o ajustamento, os testes global e data snooping foram aplicados e também foi analisada a confiabilidade da rede com o objetivo de avaliar o método proposto, além de verificar a influência do tempo de rastreio nos resultados.

  4. GEOREFERENCING IN GNSS-CHALLENGED ENVIRONMENT: INTEGRATING UWB AND IMU TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    C. K. Toth

    2017-05-01

    Full Text Available Acquiring geospatial data in GNSS compromised environments remains a problem in mapping and positioning in general. Urban canyons, heavily vegetated areas, indoor environments represent different levels of GNSS signal availability from weak to no signal reception. Even outdoors, with multiple GNSS systems, with an ever-increasing number of satellites, there are many situations with limited or no access to GNSS signals. Independent navigation sensors, such as IMU can provide high-data rate information but their initial accuracy degrades quickly, as the measurement data drift over time unless positioning fixes are provided from another source. At The Ohio State University’s Satellite Positioning and Inertial Navigation (SPIN Laboratory, as one feasible solution, Ultra- Wideband (UWB radio units are used to aid positioning and navigating in GNSS compromised environments, including indoor and outdoor scenarios. Here we report about experiences obtained with georeferencing a pushcart based sensor system under canopied areas. The positioning system is based on UWB and IMU sensor integration, and provides sensor platform orientation for an electromagnetic inference (EMI sensor. Performance evaluation results are provided for various test scenarios, confirming acceptable results for applications where high accuracy is not required.

  5. Development of the One Centimeter Accuracy Geoid Model of Latvia for GNSS Measurements

    Science.gov (United States)

    Balodis, J.; Silabriedis, G.; Haritonova, D.; Kaļinka, M.; Janpaule, I.; Morozova, K.; Jumāre, I.; Mitrofanovs, I.; Zvirgzds, J.; Kaminskis, J.; Liepiņš, I.

    2015-11-01

    There is an urgent necessity for a highly accurate and reliable geoid model to enable prompt determination of normal height with the use of GNSS coordinate determination due to the high precision requirements in geodesy, building and high precision road construction development. Additionally, the Latvian height system is in the process of transition from BAS- 77 (Baltic Height System) to EVRS2007 system. The accuracy of the geoid model must approach the precision of about ∼1 cm looking forward to the Baltic Rail and other big projects. The use of all the available and verified data sources is planned, including the use of enlarged set of GNSS/levelling data, gravimetric measurement data and, additionally, the vertical deflection measurements over the territory of Latvia. The work is going ahead stepwise. Just the issue of GNSS reference network stability is discussed. In order to achieve the ∼1 cm precision geoid, it is required to have a homogeneous high precision GNSS network as a basis for ellipsoidal height determination for GNSS/levelling points. Both the LatPos and EUPOS® - Riga network have been examined in this article.

  6. VLBI Observations of GNSS Signals on the Baseline Hobart-Ceduna

    Science.gov (United States)

    Hellerschmied, Andreas; Böhm, Johannes; Kwak, Younghee; McCallum, Jamie; Plank, Lucia

    2016-12-01

    Observing GNSS satellites with geodetic VLBI opens a variety of new possibilities, which include promising applications in the field of inter-technique frame ties. Considering GNSS satellites as co-location platforms in space, such observations provide possibilities to directly connect the dynamic GNSS and the kinematic VLBI reference frames, which may result in improved future ITRF realizations. In our research we are trying to apply observation strategies that are commonly used in geodetic VLBI, i.e., the main observables are group delays derived from direct observations of GNSS satellite signals. However, clear strategies for the data acquisition and the geodetic analysis are still missing. To pave the way towards an operational application we established a workflow to plan, correlate, observe, and analyze VLBI observations to GNSS satellites. Based on these processes we carried out several successful experiments on the Australian baseline Hobart-Ceduna in 2015 in which we observed GLONASS and GPS satellites in the L1 and L2 bands. For the first time a connected processing chain from scheduling, to correlation, to data analysis has been realized. In this contribution we introduce our workflow and present first results.

  7. A New Approach for Improving Reliability of Personal Navigation Devices under Harsh GNSS Signal Conditions

    Directory of Open Access Journals (Sweden)

    Gérard Lachapelle

    2013-11-01

    Full Text Available In natural and urban canyon environments, Global Navigation Satellite System (GNSS signals suffer from various challenges such as signal multipath, limited or lack of signal availability and poor geometry. Inertial sensors are often employed to improve the solution continuity under poor GNSS signal quality and availability conditions. Various fault detection schemes have been proposed in the literature to detect and remove biased GNSS measurements to obtain a more reliable navigation solution. However, many of these methods are found to be sub-optimal and often lead to unavailability of reliability measures, mostly because of the improper characterization of the measurement errors. A robust filtering architecture is thus proposed which assumes a heavy-tailed distribution for the measurement errors. Moreover, the proposed filter is capable of adapting to the changing GNSS signal conditions such as when moving from open sky conditions to deep canyons. Results obtained by processing data collected in various GNSS challenged environments show that the proposed scheme provides a robust navigation solution without having to excessively reject usable measurements. The tests reported herein show improvements of nearly 15% and 80% for position accuracy and reliability, respectively, when applying the above approach.

  8. Ubiquitous and Seamless Localization: Fusing GNSS Pseudoranges and WLAN Signal Strengths

    Directory of Open Access Journals (Sweden)

    Philipp Richter

    2017-01-01

    Full Text Available Ubiquitous global positioning is not feasible by GNSS alone, as it lacks accurate position fixes in dense urban centres and indoors. Hybrid positioning methods have been developed to aid GNSS in those environments. Fingerprinting localization in wireless local area networks (WLANs is a promising aiding system because of its availability, accuracy, and error mechanisms opposed to that of GNSS. This article presents a low-cost approach to ubiquitous, seamless positioning based on a particle filter integrating GNSS pseudoranges and WLAN received signal strength indicators (RSSIs. To achieve accurate location estimates indoors/outdoors and in the transition zones, appropriate likelihood functions are essential as they determine the influence of each sensor information on the position estimate. We model the spatial RSSI distributions with Gaussian processes and use these models to predict RSSIs at the particle’s positions to obtain point estimates of the RSSI likelihood function. The particle filter’s performance is assessed with real data of two test trajectories in an environment challenging for GNSS and WLAN fingerprinting localization. Outcomes of an extended Kalman filter using pseudoranges and a WLAN position as observation is included as benchmark. The proposed algorithm achieves accurate and robust seamless localization with a median accuracy of five meters.

  9. Georeferencing in Gnss-Challenged Environment: Integrating Uwb and Imu Technologies

    Science.gov (United States)

    Toth, C. K.; Koppanyi, Z.; Navratil, V.; Grejner-Brzezinska, D.

    2017-05-01

    Acquiring geospatial data in GNSS compromised environments remains a problem in mapping and positioning in general. Urban canyons, heavily vegetated areas, indoor environments represent different levels of GNSS signal availability from weak to no signal reception. Even outdoors, with multiple GNSS systems, with an ever-increasing number of satellites, there are many situations with limited or no access to GNSS signals. Independent navigation sensors, such as IMU can provide high-data rate information but their initial accuracy degrades quickly, as the measurement data drift over time unless positioning fixes are provided from another source. At The Ohio State University's Satellite Positioning and Inertial Navigation (SPIN) Laboratory, as one feasible solution, Ultra- Wideband (UWB) radio units are used to aid positioning and navigating in GNSS compromised environments, including indoor and outdoor scenarios. Here we report about experiences obtained with georeferencing a pushcart based sensor system under canopied areas. The positioning system is based on UWB and IMU sensor integration, and provides sensor platform orientation for an electromagnetic inference (EMI) sensor. Performance evaluation results are provided for various test scenarios, confirming acceptable results for applications where high accuracy is not required.

  10. Coupled Integration of CSAC, MIMU, and GNSS for Improved PNT Performance.

    Science.gov (United States)

    Ma, Lin; You, Zheng; Liu, Tianyi; Shi, Shuai

    2016-05-12

    Positioning, navigation, and timing (PNT) is a strategic key technology widely used in military and civilian applications. Global navigation satellite systems (GNSS) are the most important PNT techniques. However, the vulnerability of GNSS threatens PNT service quality, and integrations with other information are necessary. A chip scale atomic clock (CSAC) provides high-precision frequency and high-accuracy time information in a short time. A micro inertial measurement unit (MIMU) provides a strap-down inertial navigation system (SINS) with rich navigation information, better real-time feed, anti-jamming, and error accumulation. This study explores the coupled integration of CSAC, MIMU, and GNSS to enhance PNT performance. The architecture of coupled integration is designed and degraded when any subsystem fails. A mathematical model for a precise time aiding navigation filter is derived rigorously. The CSAC aids positioning by weighted linear optimization when the visible satellite number is four or larger. By contrast, CSAC converts the GNSS observations to range measurements by "clock coasting" when the visible satellite number is less than four, thereby constraining the error divergence of micro inertial navigation and improving the availability of GNSS signals and the positioning accuracy of the integration. Field vehicle experiments, both in open-sky area and in a harsh environment, show that the integration can improve the positioning probability and accuracy.

  11. A new approach for improving reliability of personal navigation devices under harsh GNSS signal conditions.

    Science.gov (United States)

    Dhital, Anup; Bancroft, Jared B; Lachapelle, Gérard

    2013-11-07

    In natural and urban canyon environments, Global Navigation Satellite System (GNSS) signals suffer from various challenges such as signal multipath, limited or lack of signal availability and poor geometry. Inertial sensors are often employed to improve the solution continuity under poor GNSS signal quality and availability conditions. Various fault detection schemes have been proposed in the literature to detect and remove biased GNSS measurements to obtain a more reliable navigation solution. However, many of these methods are found to be sub-optimal and often lead to unavailability of reliability measures, mostly because of the improper characterization of the measurement errors. A robust filtering architecture is thus proposed which assumes a heavy-tailed distribution for the measurement errors. Moreover, the proposed filter is capable of adapting to the changing GNSS signal conditions such as when moving from open sky conditions to deep canyons. Results obtained by processing data collected in various GNSS challenged environments show that the proposed scheme provides a robust navigation solution without having to excessively reject usable measurements. The tests reported herein show improvements of nearly 15% and 80% for position accuracy and reliability, respectively, when applying the above approach.

  12. Characterization of the n_TOF EAR-2 neutron beam

    Directory of Open Access Journals (Sweden)

    Chen Y.H.

    2017-01-01

    Full Text Available The experimental area 2 (EAR-2 at CERNs neutron time-of-flight facility (n_TOF, which is operational since 2014, is designed and built as a short-distance complement to the experimental area 1 (EAR-1. The Parallel Plate Avalanche Counter (PPAC monitor experiment was performed to characterize the beam pro↓le and the shape of the neutron 'ux at EAR-2. The prompt γ-flash which is used for calibrating the time-of-flight at EAR-1 is not seen by PPAC at EAR-2, shedding light on the physical origin of this γ-flash.

  13. Characterization of the n_TOF EAR-2 neutron beam

    Science.gov (United States)

    Chen, Y. H.; Tassan-Got, L.; Audouin, L.; Le Naour, C.; Durán, I.; Casarejos, E.; Aberle, O.; Andrzejewski, J.; Bécares, V.; Bacak, M.; Balibrea, J.; Barbagallo, M.; Barros, S.; Bečvář, F.; Beinrucker, C.; Berthoumieux, E.; Billowes, J.; Bosnar, D.; Brugger, M.; Caamaño, M.; Calviño, F.; Calviani, M.; Cano-Ott, D.; Cardella, R.; Casanovas, A.; Castelluccio, D. M.; Cerutti, F.; Chiaveri, E.; Colonna, N.; Cortés, G.; Cortés-Giraldo, M. A.; Cosentino, L.; Damone, L. A.; Diakaki, M.; Domingo-Pardo, C.; Dressler, R.; Dupont, E.; Fernández-Domínguez, B.; Ferrari, A.; Ferreira, P.; Finocchiaro, P.; Furman, V.; Göbel, K.; Gómez-Hornillos, M. B.; García, A. R.; Gawlik, A.; Glodariu, T.; Gonçalves, I. F.; González, E.; Goverdovski, A.; Griesmayer, E.; Guerrero, C.; Gunsing, F.; Harada, H.; Heftrich, T.; Heinitz, S.; Heyse, J.; Jenkins, D. G.; Jericha, E.; Käppeler, F.; Kadi, Y.; Katabuchi, T.; Kavrigin, P.; Ketlerov, V.; Khryachkov, V.; Kimura, A.; Kivel, N.; Kokkoris, M.; Krtička, M.; Leal-Cidoncha, E.; Lederer, C.; Leeb, H.; Lerendegui-Marco, J.; Meo, S. Lo; Lonsdale, S. J.; Losito, R.; Macina, D.; Marganiec, J.; Martínez, T.; Massimi, C.; Mastinu, P.; Mastromarco, M.; Matteucci, F.; Maugeri, E. A.; Mendoza, E.; Mengoni, A.; Milazzo, P. M.; Mingrone, F.; Mirea, M.; Montesano, S.; Musumarra, A.; Nolte, R.; Oprea, A.; Patronis, N.; Pavlik, A.; Perkowski, J.; Porras, J. I.; Praena, J.; Quesada, J. M.; Rajeev, K.; Rauscher, T.; Reifarth, R.; Riego-Perez, A.; Robles, M.; Rout, P. C.; Rubbia, C.; Ryan, J. A.; Sabaté-Gilarte, M.; Saxena, A.; Schillebeeckx, P.; Schmidt, S.; Schumann, D.; Sedyshev, P.; Smith, A. G.; Stamatopoulos, A.; Tagliente, G.; Tain, J. L.; Tarifeño-Saldivia, A.; Tsinganis, A.; Valenta, S.; Vannini, G.; Variale, V.; Vaz, P.; Ventura, A.; Vlachoudis, V.; Vlastou, R.; Wallner, A.; Warren, S.; Weigand, M.; Weiss, C.; Wolf, C.; Woods, P. J.; Wright, T.; Žugec, P.

    2017-09-01

    The experimental area 2 (EAR-2) at CERNs neutron time-of-flight facility (n_TOF), which is operational since 2014, is designed and built as a short-distance complement to the experimental area 1 (EAR-1). The Parallel Plate Avalanche Counter (PPAC) monitor experiment was performed to characterize the beam pro↓le and the shape of the neutron 'ux at EAR-2. The prompt γ-flash which is used for calibrating the time-of-flight at EAR-1 is not seen by PPAC at EAR-2, shedding light on the physical origin of this γ-flash.

  14. 3D-RTK CAPABILITY OF SINGLE GNSS RECEIVERS

    Directory of Open Access Journals (Sweden)

    W. Stempfhuber

    2013-08-01

    Full Text Available Small, aerial objects are now being utilised in many areas of civil object capture and monitoring. As a rule, the standard application of a simple GPS receiver with code solutions serves the 3D-positioning of the trajectories or recording positions. Without GPS correction information, these can be calculated at an accuracy of 10–20 metres. Corrected code solutions (DGPS generally lie in the metre range. A precise 3D-positioning of the UAV (unmanned aerial vehicle trajectories in the centimetre range provides significant improvements. In addition, the recording time of each sensor can be synchronized with the exact time stamp of the GNSS low-cost system. In recent years, increasing works on positioning from L1 GPS raw data have been published. Along with this, the carrier phase measurements with the established evaluation algorithms are analysed in the post processing method to centimetre-exact positions or to high-precision 3D trajectories [e.g. Schwieger and Gläser, 2005 or Korth and Hofmann 20011]. The use of reference information from local reference stations or a reference network serves the purpose of carrier phase ambiguity resolution. Furthermore, there are many activities worldwide in the area of PPP techniques (Precise Point Positioning. However, dual frequency receivers are primarily used in this instance. Moreover, very long initialisation times must be scheduled for this. A research project on the subject of low-cost RTK GNSS was developed for real-time applications at the Beuth Hochschule für Technik Berlin University of Applied Sciences [Stempfhuber 2012]. The overall system developed for the purpose of real-time applications with centimetre accuracy is modularly constructed and can be used for various applications (http://prof.beuthhochschule.de/stempfhuber/seite-publikation/. With hardware costing a few hundred Euro and a total weight of 500–800 g (including the battery, this system is ideally suited for UAV applications

  15. GNSS/NTRIP service and technique: accuracy tests

    Directory of Open Access Journals (Sweden)

    Jorge Pimentel Cintra

    Full Text Available Experiments conducted at the School of Engineering of the University of São Paulo, Brazil, using GNSS/NTRIP technology are described and analyzed in terms of accuracy. The method consists in using the data of a reference station, the IBGE RBMC-IP stations, collected in a remote station, by means of the Internet and a mobile phone, to obtain more accurate real time coordinates than those of the navigation method. The experiments consist in surveying the known coordinate points and of the error analysis (accuracy. Firstly with short distances (in the USP Base for Equipment Calibration, and then over increasing distances up to about 30 km, in terms of the limits foreseen for the RTK method, and for other greater distances by using the DGPS method, up to 2,700 km. The following were tested and analyzed: the use of different reference stations, the variation in accuracy over distance, the use of a L1 receiver and a L1/L2 one, as well as the use of the RTK and DGPS techniques, in terms of accuracy reached, that is, the difference between these coordinates and others considered as standard, besides checking if the equipment reaches or not the accuracy stated in the manual.

  16. 3D-RTK Capability of Single Gnss Receivers

    Science.gov (United States)

    Stempfhuber, W.

    2013-08-01

    Small, aerial objects are now being utilised in many areas of civil object capture and monitoring. As a rule, the standard application of a simple GPS receiver with code solutions serves the 3D-positioning of the trajectories or recording positions. Without GPS correction information, these can be calculated at an accuracy of 10-20 metres. Corrected code solutions (DGPS) generally lie in the metre range. A precise 3D-positioning of the UAV (unmanned aerial vehicle) trajectories in the centimetre range provides significant improvements. In addition, the recording time of each sensor can be synchronized with the exact time stamp of the GNSS low-cost system. In recent years, increasing works on positioning from L1 GPS raw data have been published. Along with this, the carrier phase measurements with the established evaluation algorithms are analysed in the post processing method to centimetre-exact positions or to high-precision 3D trajectories [e.g. Schwieger and Gläser, 2005 or Korth and Hofmann 20011]. The use of reference information from local reference stations or a reference network serves the purpose of carrier phase ambiguity resolution. Furthermore, there are many activities worldwide in the area of PPP techniques (Precise Point Positioning). However, dual frequency receivers are primarily used in this instance. Moreover, very long initialisation times must be scheduled for this. A research project on the subject of low-cost RTK GNSS was developed for real-time applications at the Beuth Hochschule für Technik Berlin University of Applied Sciences [Stempfhuber 2012]. The overall system developed for the purpose of real-time applications with centimetre accuracy is modularly constructed and can be used for various applications (http://prof.beuthhochschule.de/stempfhuber/seite-publikation/). With hardware costing a few hundred Euro and a total weight of 500-800 g (including the battery), this system is ideally suited for UAV applications. In addition, the

  17. Assimilation of GNSS radio occultation observations in GRAPES

    Science.gov (United States)

    Liu, Y.; Xue, J.

    2014-07-01

    This paper reviews the development of the global navigation satellite system (GNSS) radio occultation (RO) observations assimilation in the Global/Regional Assimilation and PrEdiction System (GRAPES) of China Meteorological Administration, including the choice of data to assimilate, the data quality control, the observation operator, the tuning of observation error, and the results of the observation impact experiments. The results indicate that RO data have a significantly positive effect on analysis and forecast at all ranges in GRAPES not only in the Southern Hemisphere where conventional observations are lacking but also in the Northern Hemisphere where data are rich. It is noted that a relatively simple assimilation and forecast system in which only the conventional and RO observation are assimilated still has analysis and forecast skill even after nine months integration, and the analysis difference between both hemispheres is gradually reduced with height when compared with NCEP (National Centers for Enviromental Prediction) analysis. Finally, as a result of the new onboard payload of the Chinese FengYun-3 (FY-3) satellites, the research status of the RO of FY-3 satellites is also presented.

  18. Simulation of ionospheric corrections regarding of solar activity on GNSS

    Energy Technology Data Exchange (ETDEWEB)

    Schlueter, S.; Engler, E. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V., Neustrelitz (Germany)

    1999-07-01

    Future use of satellite navigation systems in transportation, especially in aviation and shipping, will make great demands on precision and integrity of existing new systems. As a first step in the direction of a GNSS, the US, Japan and Europe are building up the GPS augmentation systems WAAS, MSAS and EGNOS to improve the current situation in navigation and positioning. The improvement of existing as well as the development of new systems needs suitable simulation tools for design and validation. In this context the projects NavSim and SatNav SIMplus have to be seen. They are parts of the cooperation agreements between DLR (Deutsches Zentrum fuer Luft- und Raumfahrt) and DSS (Daymler Chrysler Aerospace, Dornier Satellitensystem GmbH). Both projects complement on another on the way to establish and end-to-end software simulator for navigation systems. Here we present some preliminary simulations based on the ionospheric module of the NavSim simulator taking into account the situation of high solar activity in the years 2000-2001. (orig.)

  19. Overview of the recombinant proteins purification by affinity tags and ...

    African Journals Online (AJOL)

    From protein within isolation process which the same matter increases labor costs further and prevents application of these tags in industrial scale. Therefore proper replacement is emphasized for enzymatic removal of purification tags. Keywords: protein purification; recombinant proteins; self-cleavable tags; Intein tags; ...

  20. Annotating images by harnessing worldwide user-tagged photos

    NARCIS (Netherlands)

    Li, X.; Snoek, C.G.M.; Worring, M.

    2009-01-01

    Automatic image tagging is important yet challenging due to the semantic gap and the lack of learning examples to model a tag's visual diversity. Meanwhile, social user tagging is creating rich multimedia content on the Web. In this paper, we propose to combine the two tagging approaches in a

  1. Prenatal and postnatal development of the mammalian ear.

    Science.gov (United States)

    Powles-Glover, Nicola; Maconochie, Mark

    2018-02-15

    The ear can be subdivided into three distinct parts, each with significantly distinct structural and functional differences, the outer, middle, and inner ear, the latter housing the specialized sensory hair cells that act as transducers. There are numerous manuscripts documenting the anatomical development of the inner, middle, and outer ear in humans, rodents, chick, and zebrafish, dating back to the early 20th Century, and these developmental processes of these components are further compared in a number of review articles (Anthwal & Thompson, ; Basch, Brown, Jen, & Groves, ; Sai & Ladher, ). This article presents a review of both pre- and postnatal development of the inner ear, discusses recent molecular genetic advances toward our understanding of hair cells responsible for the sensory functions of the inner ear. Finally, a survey of comparative ear biology is used to pull together our understanding of the species differences, similarities, and key time points of definitive organ development of the ear. © 2017 Wiley Periodicals, Inc.

  2. Associated Particle Tagging (APT) in Magnetic Spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, David V.; Baciak, James E.; Stave, Sean C.; Chichester, David; Dale, Daniel; Kim, Yujong; Harmon, Frank

    2012-10-16

    Summary In Brief The Associated Particle Tagging (APT) project, a collaboration of Pacific Northwest National Laboratory (PNNL), Idaho National Laboratory (INL) and the Idaho State University (ISU)/Idaho Accelerator Center (IAC), has completed an exploratory study to assess the role of magnetic spectrometers as the linchpin technology in next-generation tagged-neutron and tagged-photon active interrogation (AI). The computational study considered two principle concepts: (1) the application of a solenoidal alpha-particle spectrometer to a next-generation, large-emittance neutron generator for use in the associated particle imaging technique, and (2) the application of tagged photon beams to the detection of fissile material via active interrogation. In both cases, a magnetic spectrometer momentum-analyzes charged particles (in the neutron case, alpha particles accompanying neutron generation in the D-T reaction; in the tagged photon case, post-bremsstrahlung electrons) to define kinematic properties of the relevant neutral interrogation probe particle (i.e. neutron or photon). The main conclusions of the study can be briefly summarized as follows: Neutron generator: • For the solenoidal spectrometer concept, magnetic field strengths of order 1 Tesla or greater are required to keep the transverse size of the spectrometer smaller than 1 meter. The notional magnetic spectrometer design evaluated in this feasibility study uses a 5-T magnetic field and a borehole radius of 18 cm. • The design shows a potential for 4.5 Sr tagged neutron solid angle, a factor of 4.5 larger than achievable with current API neutron-generator designs. • The potential angular resolution for such a tagged neutron beam can be less than 0.5o for modest Si-detector position resolution (3 mm). Further improvement in angular resolution can be made by using Si-detectors with better position resolution. • The report documents several features of a notional generator design incorporating the

  3. Methodologies for Improved Tag Cloud Generation with Clustering

    DEFF Research Database (Denmark)

    Leginus, Martin; Dolog, Peter; Lage, Ricardo Gomes

    2012-01-01

    Tag clouds are useful means for navigation in the social web systems. Usually the systems implement the tag cloud generation based on tag popularity which is not always the best method. In this paper we propose methodologies on how to combine clustering into the tag cloud generation to improve...... coverage and overlap. We study several clustering algorithms to generate tag clouds. We show that by extending cloud generation based on tag popularity with clustering we slightly improve coverage. We also show that if the cloud is generated by clustering independently of the tag popularity baseline we...

  4. Analytical model of internally coupled ears

    DEFF Research Database (Denmark)

    Vossen, Christine; Christensen-Dalsgaard, Jakob; Leo van Hemmen, J

    2010-01-01

    differences in the tympanic membrane vibrations. Both cues show strong directionality. The work presented herein sets out the derivation of a three dimensional analytical model of internally coupled ears that allows for calculation of a complete vibration profile of the membranes. The analytical model...... additionally provides the opportunity to incorporate the effect of the asymmetrically attached columella, which leads to the activation of higher membrane vibration modes. Incorporating this effect, the analytical model can explain measurements taken from the tympanic membrane of a living lizard, for example......, data demonstrating an asymmetrical spatial pattern of membrane vibration. As the analytical calculations show, the internally coupled ears increase the directional response, appearing in large directional internal amplitude differences (iAD) and in large internal time differences (iTD). Numerical...

  5. SparkClouds: visualizing trends in tag clouds.

    Science.gov (United States)

    Lee, Bongshin; Riche, Nathalie Henry; Karlson, Amy K; Carpendale, Sheelash

    2010-01-01

    Tag clouds have proliferated over the web over the last decade. They provide a visual summary of a collection of texts by visually depicting the tag frequency by font size. In use, tag clouds can evolve as the associated data source changes over time. Interesting discussions around tag clouds often include a series of tag clouds and consider how they evolve over time. However, since tag clouds do not explicitly represent trends or support comparisons, the cognitive demands placed on the person for perceiving trends in multiple tag clouds are high. In this paper, we introduce SparkClouds, which integrate sparklines into a tag cloud to convey trends between multiple tag clouds. We present results from a controlled study that compares SparkClouds with two traditional trend visualizations—multiple line graphs and stacked bar charts—as well as Parallel Tag Clouds. Results show that SparkClouds ability to show trends compares favourably to the alternative visualizations.

  6. A brief examination of optical tagging technologies.

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, Mark R.; Cahill, Paul A. (Aspecular Optics, Dayton, OH); Drummond, Timothy J.; Wilcoxon, Jess Patrick

    2003-07-01

    Presented within this report are the results of a brief examination of optical tagging technologies funded by the Laboratory Directed Research and Development (LDRD) program at Sandia National Laboratories. The work was performed during the summer months of 2002 with total funding of $65k. The intent of the project was to briefly examine a broad range of approaches to optical tagging concentrating on the wavelength range between ultraviolet (UV) and the short wavelength infrared (SWIR, {lambda} < 2{micro}m). Tagging approaches considered include such things as simple combinations of reflective and absorptive materials closely spaced in wavelength to give a high contrast over a short range of wavelengths, rare-earth oxides in transparent binders to produce a narrow absorption line hyperspectral tag, and fluorescing materials such as phosphors, dies and chemically precipitated particles. One technical approach examined in slightly greater detail was the use of fluorescing nano particles of metals and semiconductor materials. The idea was to embed such nano particles in an oily film or transparent paint binder. When pumped with a SWIR laser such as that produced by laser diodes at {lambda}=1.54{micro}m, the particles would fluoresce at slightly longer wavelengths, thereby giving a unique signal. While it is believed that optical tags are important for military, intelligence and even law enforcement applications, as a business area, tags do not appear to represent a high on return investment. Other government agencies frequently shop for existing or mature tag technologies but rarely are interested enough to pay for development of an untried technical approach. It was hoped that through a relatively small investment of laboratory R&D funds, enough technologies could be identified that a potential customers requirements could be met with a minimum of additional development work. Only time will tell if this proves to be correct.

  7. Mouse middle ear ion homeostasis channels and intercellular junctions.

    Directory of Open Access Journals (Sweden)

    Lisa M Morris

    Full Text Available The middle ear contains homeostatic mechanisms that control the movement of ions and fluids similar to those present in the inner ear, and are altered during inflammation.The normal middle ear cavity is fluid-free and air-filled to allow for effective sound transmission. Within the inner ear, the regulation of fluid and ion movement is essential for normal auditory and vestibular function. The same ion and fluid channels active in the inner ear may have similar roles with fluid regulation in the middle ear.Middle and inner ears from BALB/c mice were processed for immunohistochemistry of 10 specific ion homeostasis factors to determine if similar transport and barrier mechanisms are present in the tympanic cavity. Examination also was made of BALB/c mice middle ears after transtympanic injection with heat-killed Haemophilus influenza to determine if these channels are impacted by inflammation.The most prominent ion channels in the middle ear included aquaporins 1, 4 and 5, claudin 3, ENaC and Na(+,K(+-ATPase. Moderate staining was found for GJB2, KCNJ10 and KCNQ1. The inflamed middle ear epithelium showed increased staining due to expected cellular hypertrophy. Localization of ion channels was preserved within the inflamed middle ear epithelium.The middle ear epithelium is a dynamic environment with intrinsic mechanisms for the control of ion and water transport to keep the middle ear clear of fluids. Compromise of these processes during middle ear disease may underlie the accumulation of effusions and suggests they may be a therapeutic target for effusion control.

  8. Gentamicin Pharmacokinetics in the Chicken Inner Ear

    OpenAIRE

    Bunting, Eric C.; Park, Debra L.; Durham, Dianne; Girod, Douglas A.

    2004-01-01

    Avians have the unique ability to regenerate cochlear hair cells that are lost due to ototoxins or excessive noise. Many methodological techniques are available to damage the hair cells for subsequent scientific study. A recent method utilizes topical application of an ototoxic drug to the round window membrane. The current study examines the pharmacokinetics of gentamicin in the inner ear of chickens following topical application to the round window membrane or a single system...

  9. MAPPING GNSS RESTRICTED ENVIRONMENTS WITH A DRONE TANDEM AND INDIRECT POSITION CONTROL

    Directory of Open Access Journals (Sweden)

    E. Cledat

    2017-08-01

    Full Text Available The problem of autonomously mapping highly cluttered environments, such as urban and natural canyons, is intractable with the current UAV technology. The reason lies in the absence or unreliability of GNSS signals due to partial sky occlusion or multi-path effects. High quality carrier-phase observations are also required in efficient mapping paradigms, such as Assisted Aerial Triangulation, to achieve high ground accuracy without the need of dense networks of ground control points. In this work we consider a drone tandem in which the first drone flies outside the canyon, where GNSS constellation is ideal, visually tracks the second drone and provides an indirect position control for it. This enables both autonomous guidance and accurate mapping of GNSS restricted environments without the need of ground control points. We address the technical feasibility of this concept considering preliminary real-world experiments in comparable conditions and we perform a mapping accuracy prediction based on a simulation scenario.

  10. A High-Level Functional Architecture for GNSS-Based Road Charging Systems

    DEFF Research Database (Denmark)

    Zabic, Martina

    2011-01-01

    charging systems, it is important to highlight the overall system architecture which is the framework that defines the basic functions and important concepts of the system. This paper presents a functional architecture for GNSS-based road charging systems based on the concepts of system engineering. First......, a short introduction is provided followed by a presentation of the system engineering methodology to illustrate how and why system architectures can be beneficial for GNSS-based road charging systems. Hereafter, a basic set of system functions is determined based on functional system requirements, which......Within recent years, GNSS-based road charging systems have been highly profiled on the policy makers’ agenda. These types of systems are however technically challenging and are considered one of the most complex types of charging systems. To understand the structure and behavior of such road...

  11. Mapping Gnss Restricted Environments with a Drone Tandem and Indirect Position Control

    Science.gov (United States)

    Cledat, E.; Cucci, D. A.

    2017-08-01

    The problem of autonomously mapping highly cluttered environments, such as urban and natural canyons, is intractable with the current UAV technology. The reason lies in the absence or unreliability of GNSS signals due to partial sky occlusion or multi-path effects. High quality carrier-phase observations are also required in efficient mapping paradigms, such as Assisted Aerial Triangulation, to achieve high ground accuracy without the need of dense networks of ground control points. In this work we consider a drone tandem in which the first drone flies outside the canyon, where GNSS constellation is ideal, visually tracks the second drone and provides an indirect position control for it. This enables both autonomous guidance and accurate mapping of GNSS restricted environments without the need of ground control points. We address the technical feasibility of this concept considering preliminary real-world experiments in comparable conditions and we perform a mapping accuracy prediction based on a simulation scenario.

  12. An adaptive deep-coupled GNSS/INS navigation system with hybrid pre-filter processing

    Science.gov (United States)

    Wu, Mouyan; Ding, Jicheng; Zhao, Lin; Kang, Yingyao; Luo, Zhibin

    2018-02-01

    The deep-coupling of a global navigation satellite system (GNSS) with an inertial navigation system (INS) can provide accurate and reliable navigation information. There are several kinds of deeply-coupled structures. These can be divided mainly into coherent and non-coherent pre-filter based structures, which have their own strong advantages and disadvantages, especially in accuracy and robustness. In this paper, the existing pre-filters of the deeply-coupled structures are analyzed and modified to improve them firstly. Then, an adaptive GNSS/INS deeply-coupled algorithm with hybrid pre-filters processing is proposed to combine the advantages of coherent and non-coherent structures. An adaptive hysteresis controller is designed to implement the hybrid pre-filters processing strategy. The simulation and vehicle test results show that the adaptive deeply-coupled algorithm with hybrid pre-filters processing can effectively improve navigation accuracy and robustness, especially in a GNSS-challenged environment.

  13. Evaluation of RTKLIB's Positioning Accuracy Using low-cost GNSS Receiver and ASG-EUPOS

    Directory of Open Access Journals (Sweden)

    Bartosz Wisniewski

    2013-03-01

    Full Text Available The paper focuses on a comparison of different positioning methods provided by free and open source software (FOSS package called RTKLIB. The RTKLIB supports real-time and post-processed positioning. The most important modes of operation tested by the authors are Kinematic, Static, Fixed and Precise Point Positioning (PPP. The data for evaluation were obtained from low-cost Global Navigation Satellite System (GNSS receiver. The tested receiver was based on the u-blox's LEA-6T GNSS module. This receiver provides different types of information including raw carrier phase measurements. It gives the possibility for centimeter-level precision of positioning. As the supporting source of data ASG-EUPOS system was used. ASG-EUPOS is a Polish network of GNSS reference stations providing the real-time corrections and post processing services for the entire territory of Poland.

  14. GNSS-based Road Charging Systems - Assessment of Vehicle Location Determination

    DEFF Research Database (Denmark)

    Zabic, Martina

    the collected data from the experiment, in its original for, as it would be used as input for the automated charge calculation process in a road charging system. Furthermore, new methodologies are developed for assessing the performance of the vehicle location determination function in terms of data reliability......An increasing demand for satellite-based road charging systems is developing in Europe. Satellite-based road charging involves charging road users for their road usage by allowing the vehicles to locate themselves within a certain charge area using Global Navigation Satellite Systems (GNSS......). The research presented in this thesis deals with the performance and technological challenges of vehicle location determination within GNSS-based road charging systems. GNSS-based road charging systems may take on a number of different forms. Depending on the charging objective, these road charging systems can...

  15. A hybrid data fusion method for GNSS/INS integration navigation system

    Science.gov (United States)

    Yang, Ling; Li, Bofeng; Shen, Yunzhong; Li, Haojun

    2017-04-01

    Although DGNSS is widely used and PPP-GNSS is nowadays a viable precise positioning technology option, the major disadvantage of GNSS still remains: signal blockage due to obstructions in urban and built up environments, and extreme power attenuation of the signals when operated indoors. The combination of GNSS with other sensors, such as a self-contained inertial navigation system (INS), provides an ideal position and attitude determination solution which can not only mitigate the weakness of GNSS, but also bound the INS error that otherwise would grow with time when the INS operates alone. However, the navigation accuracy provided by GNSS/INS strongly depends on the quality and geometry of the GNSS observations, the quality of the INS technology used, and the integration model applied. There are two main types of coupled schemes for integration systems: loosely coupled integration and tightly coupled integration. In loosely coupled integration, position measurements are taken from both systems and combined optimally, usually in a Kalman filter. Tightly coupled integration directly combines the raw pseudorange or carrier phase measurements of GNSS with inertial measurements in an extended Kalman filter. The latter technique improves the ability to resolve ambiguities, i.e. allows a quicker recovery from outage events such as a loss of signal under vegetation. In recent years, tightly coupled differential carrier phase GNSS/INS integration has become popular, because it has the advantage of providing accurate position information even when GPS measurements are rank-deficient in stand-alone processing and is theoretically optimal in a filtering sense, especially in urban navigation applications. However, the heavier computational burden and sensor communication usually complicate the tightly coupled integration and reduce the system efficiency, compared with the loosely coupled integration. In this paper, it has been proved that the loosely coupled and tightly

  16. Precise Orbit Determination for LEO Spacecraft Using GNSS Tracking Data from Multiple Antennas

    Science.gov (United States)

    Kuang, Da; Bertiger, William; Desai, Shailen; Haines, Bruce

    2010-01-01

    To support various applications, certain Earth-orbiting spacecrafts (e.g., SRTM, COSMIC) use multiple GNSS antennas to provide tracking data for precise orbit determination (POD). POD using GNSS tracking data from multiple antennas poses some special technical issues compared to the typical single-antenna approach. In this paper, we investigate some of these issues using both real and simulated data. Recommendations are provided for POD with multiple GNSS antennas and for antenna configuration design. The observability of satellite position with multiple antennas data is compared against single antenna case. The impact of differential clock (line biases) and line-of-sight (up, along-track, and cross-track) on kinematic and reduced-dynamic POD is evaluated. The accuracy of monitoring the stability of the spacecraft structure by simultaneously performing POD of the spacecraft and relative positioning of the multiple antennas is also investigated.

  17. GNSS-R Altimetry Performance Analysis for the GEROS Experiment on Board the International Space Station.

    Science.gov (United States)

    Camps, Adriano; Park, Hyuk; Sekulic, Ivan; Rius, Juan Manuel

    2017-07-06

    The GEROS-ISS (GNSS rEflectometry, Radio Occultation and Scatterometry onboard International Space Station) is an innovative experiment for climate research, proposed in 2011 within a call of the European Space Agency (ESA). This proposal was the only one selected for further studies by ESA out of ~25 ones that were submitted. In this work, the instrument performance for the near-nadir altimetry (GNSS-R) mode is assessed, including the effects of multi-path in the ISS structure, the electromagnetic-bias, and the orbital height decay. In the absence of ionospheric scintillations, the altimetry rms error is GNSS spacecrafts), mission requirements (rms error is 20 dB at equatorial regions, mainly after sunset, which will seriously degrade the altimetry and the scatterometry performances of the instrument.

  18. Systematic error mitigation in multi-GNSS positioning based on semiparametric estimation

    Science.gov (United States)

    Yu, Wenkun; Ding, Xiaoli; Dai, Wujiao; Chen, Wu

    2017-12-01

    Joint use of observations from multiple global navigation satellite systems (GNSS) is advantageous in high-accuracy positioning. However, systematic errors in the observations can significantly impact on the positioning accuracy if such errors cannot be properly mitigated. The errors can distort least squares estimations and also affect the results of variance component estimation that is frequently used to determine the stochastic model when observations from multiple GNSS are used. We present an approach that is based on the concept of semiparametric estimation for mitigating the effects of the systematic errors. Experimental results based on both simulated and real GNSS datasets show that the approach is effective, especially when applied before carrying out variance component estimation.

  19. Refining the GPS Space Service Volume (SSV) and Building a Multi-GNSS SSV

    Science.gov (United States)

    Parker, Joel J. K.

    2017-01-01

    The GPS (Global Positioning System) Space Service Volume (SSV) was first defined to protect the GPS main lobe signals from changes from block to block. First developed as a concept by NASA in 2000, it has been adopted for the GPS III block of satellites, and is being used well beyond the current specification to enable increased navigation performance for key missions like GOES-R. NASA has engaged the US IFOR (Interagency Forum Operational Requirements) process to adopt a revised requirement to protect this increased and emerging use. Also, NASA is working through the UN International Committee on GNSS (Global Navigation Satellite System) to develop an interoperable multi-GNSS SSV in partnership with all of the foreign GNSS providers.

  20. Why Do Elephants Flap Their Ears?

    Science.gov (United States)

    Koffi, Moise; Jiji, Latif; Andreopoulos, Yiannis

    2009-11-01

    It is estimated that a 4200 kg elephant generates as much as 5.12 kW of heat. How the elephant dissipates its metabolic heat and regulates its body temperature has been investigated during the past seven decades. Findings and conclusions differ sharply. The high rate of metabolic heat coupled with low surface area to volume ratio and the absence of sweat glands eliminate surface convection as the primary mechanism for heat removal. Noting that the elephant ears have high surface area to volume ratio and an extensive vascular network, ear flapping is thought to be the principal thermoregulatory mechanism. A computational and experimental program is carried out to examine flow and heat transfer characteristics. The ear is modeled as a uniformly heated oscillating rectangular plate. Our computational work involves a three-dimensional time dependent CFD code with heat transfer capabilities to obtain predictions of the flow field and surface temperature distributions. This information was used to design an experimental setup with a uniformly heated plate of size 0.2m x 0.3m oscillating at 1.6 cycles per second. Results show that surface temperature increases and reaches a steady periodic oscillation after a period of transient oscillation. The role of the vortices shed off the plate in heat transfer enhancement will be discussed.

  1. The glue ear 'epidemic': a historical perspective.

    Science.gov (United States)

    Alderson, David

    2011-12-01

    This paper explores the historical context of the dramatic rise in surgery for glue ear in the mid-20th century, and questions the published assertion that this represented a manufactured 'epidemic'. In examining historical sources, the reader's theoretical viewpoint greatly influences their conclusions: the sustained rise in treatment for glue ear may be seen as the advance of science in a golden age or the resistance of insular professionals to reason in the light of new scientific study methods. Current views on the practice of medicine, consumerism, science and standardisation, rationing and the nature of 'truth' all affect the way that we see this period. Technological advances clearly allowed better diagnosis and more effective treatment, but these did not appear to drive an 'epidemic', rather they were developed to meet the pre-existing challenges of otological practice. The proposition that an 'epidemic' was created does not appear to have any solid grounding. Society's perception of what constitutes disease and what needs treatment may have evolved, but the prevalence of other important diseases changed dramatically over this time period, and a real change in the epidemiology of glue ear cannot be dismissed. In defining the case for and against surgical treatment, a solely positivist, quantitative worldview cannot give us a complete picture of benefit and risk to individuals, families and society at large.

  2. Notch signaling and the developing inner ear.

    Science.gov (United States)

    Murata, Junko; Ikeda, Katsuhisa; Okano, Hideyuki

    2012-01-01

    Sensory hair cells (HCs) and their associated nonsensory supporting cells (SCs) exhibit a typical mosaic pattern in each of the sensory patches in the inner ear. Notch signaling has been considered to conduct the formation of this mosaic pattern through one of its famous functions, known as 'lateral inhibition'. The two Notch ligands Delta-like1 and Jagged2 are believed to act synergistically at the stage of cell diversification in mammals. In addition, many current studies suggest that Notch signaling has another inductive, but not inhibiting, role in the determination of the prosensory region, which precedes the cell diversification of HCs and SCs and Jagged1 is thought to be an essential ligand in this process. Earlier in ear development, the first cell fate determination begins with the delamination of the neuroblasts from the otic epithelium. The delaminated neuroblasts migrate and coalesce to form cochleovestibular ganglion. Notch signaling pathway is thought to function during the delamination through its lateral inhibitory mechanism. Recently, many experiments examining Notch-related gene expression patterns and direct functional analyses of genes have revealed multiple important functions of Notch in inner ear development. Here, we survey a series of studies and discuss the issues that remain to be elucidated in the future.

  3. Tag and Neighbor based Recommender systems for Medical events

    DEFF Research Database (Denmark)

    Bayyapu, Karunakar Reddy; Dolog, Peter

    2010-01-01

    This paper presents an extension of a multifactor recommendation approach based on user tagging with term neighbours. Neighbours of words in tag vectors and documents provide for hitting larger set of documents and not only those matching with direct tag vectors or content of the documents. Tag...... in the situations where the quality of tags is lower. We discuss the approach on the examples from the existing Medworm system to indicate the usefulness of the approach....

  4. Tag and Neighbor based Recommender systems for Medical events

    DEFF Research Database (Denmark)

    Bayyapu, Karunakar Reddy; Dolog, Peter

    This paper presents an extension of a multifactor recommendation approach based on user tagging with term neighbours. Neighbours of words in tag vectors and documents provide for hitting larger set of documents and not only those matching with direct tag vectors or content of the documents. Tag...... in the situations where the quality of tags is lower. We discuss the approach on the examples from the existing Medworm system to indicate the usefulness of the approach....

  5. Evaluation of visible implant elastomer tags in zebrafish (Danio rerio

    Directory of Open Access Journals (Sweden)

    Claudia Hohn

    2013-11-01

    The use of the visible implant elastomer (VIE tagging system in zebrafish (Danio rerio was examined. Two tag orientations (horizontal and vertical at the dorsal fin base were tested for tag retention, tag fragmentation and whether VIE tags affected growth and survival of juvenile zebrafish (1–4 month post hatch. Six tag locations (abdomen, anal fin base, caudal peduncle, dorsal fin base, pectoral fin base, isthmus and 5 tag colors (yellow, red, pink, orange, blue were evaluated for ease of VIE tag application and tag visibility in adult zebrafish. Long-term retention (1 year and multiple tagging sites (right and left of dorsal fin and pectoral fin base were examined in adult zebrafish. Lastly, survival of recombination activation gene 1−/− (rag1−/− zebrafish was evaluated after VIE tagging. The best tag location was the dorsal fin base, and the most visible tag color was pink. Growth rate of juvenile zebrafish was not affected by VIE tagging. Horizontal tagging is recommended in early stages of fish growth (1–2 months post hatch. VIE tags were retained for 1 year and tagging did not interfere with long-term growth and survival. There was no mortality associated with VIE tagging in rag1−/− zebrafish. The VIE tagging system is highly suitable for small-sized zebrafish. When familiar with the procedure, 120 adult zebrafish can be tagged in one hour. It does not increase mortality in adult zebrafish or interfere with growth in juvenile or adult zebrafish.

  6. Tag-to-Tag Interference Suppression Technique Based on Time Division for RFID

    Directory of Open Access Journals (Sweden)

    Grishma Khadka

    2017-01-01

    Full Text Available Radio-frequency identification (RFID is a tracking technology that enables immediate automatic object identification and rapid data sharing for a wide variety of modern applications using radio waves for data transmission from a tag to a reader. RFID is already well established in technical areas, and many companies have developed corresponding standards and measurement techniques. In the construction industry, effective monitoring of materials and equipment is an important task, and RFID helps to improve monitoring and controlling capabilities, in addition to enabling automation for construction projects. However, on construction sites, there are many tagged objects and multiple RFID tags that may interfere with each other’s communications. This reduces the reliability and efficiency of the RFID system. In this paper, we propose an anti-collision algorithm for communication between multiple tags and a reader. In order to suppress interference signals from multiple neighboring tags, the proposed algorithm employs the time-division (TD technique, where tags in the interrogation zone are assigned a specific time slot so that at every instance in time, a reader communicates with tags using the specific time slot. We present representative computer simulation examples to illustrate the performance of the proposed anti-collision technique for multiple RFID tags.

  7. Middle-ear velocity transfer function, cochlear input immittance, and middle-ear efficiency in chinchilla

    Science.gov (United States)

    Ravicz, Michael E.; Rosowski, John J.

    2013-01-01

    The transfer function HV between stapes velocity VS and sound pressure near the tympanic membrane PTM is a descriptor of sound transmission through the middle ear (ME). The ME power transmission efficiency (MEE), the ratio of sound power entering the cochlea to power entering the middle ear, was computed from HV measured in seven chinchilla ears and previously reported measurements of ME input admittance YTM and ME pressure gain GMEP [Ravicz and Rosowski, J. Acoust. Soc. Am. 132, 2437–2454 (2012); J. Acoust. Soc. Am. 133, 2208–2223 (2013)] in the same ears. The ME was open, and a pressure sensor was inserted into the cochlear vestibule for most measurements. The cochlear input admittance YC computed from HV and GMEP is controlled by a combination of mass and resistance and is consistent with a minimum-phase system up to 27 kHz. The real part Re{YC}, which relates cochlear sound power to inner-ear sound pressure, decreased gradually with frequency up to 25 kHz and more rapidly above that. MEE was about 0.5 between 0.1 and 8 kHz, higher than previous estimates in this species, and decreased sharply at higher frequencies. PMID:24116422

  8. An efficient solution of real-time data processing for multi-GNSS network

    Science.gov (United States)

    Gong, Xiaopeng; Gu, Shengfeng; Lou, Yidong; Zheng, Fu; Ge, Maorong; Liu, Jingnan

    2017-12-01

    Global navigation satellite systems (GNSS) are acting as an indispensable tool for geodetic research and global monitoring of the Earth, and they have been rapidly developed over the past few years with abundant GNSS networks, modern constellations, and significant improvement in mathematic models of data processing. However, due to the increasing number of satellites and stations, the computational efficiency becomes a key issue and it could hamper the further development of GNSS applications. In this contribution, this problem is overcome from the aspects of both dense linear algebra algorithms and GNSS processing strategy. First, in order to fully explore the power of modern microprocessors, the square root information filter solution based on the blocked QR factorization employing as many matrix-matrix operations as possible is introduced. In addition, the algorithm complexity of GNSS data processing is further decreased by centralizing the carrier-phase observations and ambiguity parameters, as well as performing the real-time ambiguity resolution and elimination. Based on the QR factorization of the simulated matrix, we can conclude that compared to unblocked QR factorization, the blocked QR factorization can greatly improve processing efficiency with a magnitude of nearly two orders on a personal computer with four 3.30 GHz cores. Then, with 82 globally distributed stations, the processing efficiency is further validated in multi-GNSS (GPS/BDS/Galileo) satellite clock estimation. The results suggest that it will take about 31.38 s per epoch for the unblocked method. While, without any loss of accuracy, it only takes 0.50 and 0.31 s for our new algorithm per epoch for float and fixed clock solutions, respectively.

  9. Applying the GNSS Volcanic Ash Plume Detection Technique to Consumer Navigation Receivers

    Science.gov (United States)

    Rainville, N.; Palo, S.; Larson, K. M.

    2017-12-01

    Global Navigation Satellite Systems (GNSS) such as the Global Positioning System (GPS) rely on predictably structured and constant power RF signals to fulfill their primary use for navigation and timing. When the received strength of GNSS signals deviates from the expected baseline, it is typically due to a change in the local environment. This can occur when signal reflections from the ground are modified by changes in snow or soil moisture content, as well as by attenuation of the signal from volcanic ash. This effect allows GNSS signals to be used as a source for passive remote sensing. Larson et al. (2017) have developed a detection technique for volcanic ash plumes based on the attenuation seen at existing geodetic GNSS sites. Since these existing networks are relatively sparse, this technique has been extended to use lower cost consumer GNSS receiver chips to enable higher density measurements of volcanic ash. These low-cost receiver chips have been integrated into a fully stand-alone sensor, with independent power, communications, and logging capabilities as part of a Volcanic Ash Plume Receiver (VAPR) network. A mesh network of these sensors transmits data to a local base-station which then streams the data real-time to a web accessible server. Initial testing of this sensor network has uncovered that a different detection approach is necessary when using consumer GNSS receivers and antennas. The techniques to filter and process the lower quality data from consumer receivers will be discussed and will be applied to initial results from a functioning VAPR network installation.

  10. Understanding Transient Forcing with Plasma Instability Model, Ionospheric Propagation Model and GNSS Observations

    Science.gov (United States)

    Deshpande, K.; Zettergren, M. D.; Datta-Barua, S.

    2017-12-01

    Fluctuations in the Global Navigation Satellite Systems (GNSS) signals observed as amplitude and phase scintillations are produced by plasma density structures in the ionosphere. Phase scintillation events in particular occur due to structures at Fresnel scales, typically about 250 meters at ionospheric heights and GNSS frequency. Likely processes contributing to small-scale density structuring in auroral and polar regions include ionospheric gradient-drift instability (GDI) and Kelvin-Helmholtz instability (KHI), which result, generally, from magnetosphere-ionosphere interactions (e.g. reconnection) associated with cusp and auroral zone regions. Scintillation signals, ostensibly from either GDI or KHI, are frequently observed in the high latitude ionosphere and are potentially useful diagnostics of how energy from the transient forcing in the cusp or polar cap region cascades, via instabilities, to small scales. However, extracting quantitative details of instabilities leading to scintillation using GNSS data drastically benefits from both a model of the irregularities and a model of GNSS signal propagation through irregular media. This work uses a physics-based model of the generation of plasma density irregularities (GEMINI - Geospace Environment Model of Ion-Neutral Interactions) coupled to an ionospheric radio wave propagation model (SIGMA - Satellite-beacon Ionospheric-scintillation Global Model of the upper Atmosphere) to explore the cascade of density structures from medium to small (sub-kilometer) scales. Specifically, GEMINI-SIGMA is used to simulate expected scintillation from different instabilities during various stages of evolution to determine features of the scintillation that may be useful to studying ionospheric density structures. Furthermore we relate the instabilities producing GNSS scintillations to the transient space and time-dependent magnetospheric phenomena and further predict characteristics of scintillation in different geophysical

  11. High-rate multi-GNSS: what does it mean to seismology?

    Science.gov (United States)

    Geng, J.

    2017-12-01

    GNSS precise point positioning (PPP) is capable of measuring centimeter-level positions epoch by epoch at a single station, and is thus treasured in tsunami/earthquake early warning where static displacements in the near field are critical to rapidly and reliably determining the magnitude of destructive events. However, most operational real-time PPP systems at present rely on only GPS data. The deficiency of such systems is that the high reliability and availability of precise displacements cannot be maintained continuously in real time, which is however a crucial requirement for disaster resistance and response. Multi-GNSS, including GLONASS, BeiDou, Galileo and QZSS other than only GPS, can be a solution to this problem because much more satellites per epoch (e.g. 30-40) will be available. In this case, positioning failure due to data loss or blunders can be minimized, and on the other hand, positioning initializations can be accelerated to a great extent since the satellite geometry for each epoch will be enhanced enormously. We established a prototype real-time multi-GNSS PPP service based on Asia-Pacific real-time network which can collect and stream high-rate data from all five navigation systems above. We estimated high-rate satellite clock corrections and enabled undifferenced ambiguity fixing for multi-GNSS, which therefore ensures high availability and reliability of precise displacement estimates in contrast to GPS-only systems. We will report how we can benefit from multi-GNSS for seismology, especially the noise characteristics of high-rate and sub-daily displacements. We will also use storm surge loading events to demonstrate the contribution of multi-GNSS to sub-daily transient signals.

  12. LATENCY DETERMINATION AND COMPENSATION IN REAL-TIME GNSS/INS INTEGRATED NAVIGATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    P. D. Solomon

    2012-09-01

    Full Text Available Unmanned Aerial Vehicle (UAV technology is now commonplace in many defence and civilian environments. However, the high cost of owning and operating a sophisticated UAV has slowed their adoption in many commercial markets. Universities and research groups are actively experimenting with UAVs to further develop the technology, particularly for automated flying operations. The two main UAV platforms used are fixed-wing and helicopter. Helicopter-based UAVs offer many attractive features over fixed-wing UAVs, including vertical take-off, the ability to loiter, and highly dynamic flight. However the control and navigation of helicopters are significantly more demanding than those of fixed-wing UAVs and as such require a high bandwidth real-time Position, Velocity, Attitude (PVA navigation system. In practical Real-Time Navigation Systems (RTNS there are delays in the processing of the GNSS data prior to the fusion of the GNSS data with the INS measurements. This latency must be compensated for otherwise it degrades the solution of the navigation filter. This paper investigates the effect of latency in the arrival time of the GNSS data in a RTNS. Several test drives and flights were conducted with a low-cost RTNS, and compared with a high quality GNSS/INS solution. A technique for the real-time, automated and accurate estimation of the GNSS latency in low-cost systems was developed and tested. The latency estimates were then verified through cross-correlation with the time-stamped measurements from the reference system. A delayed measurement Extended Kalman Filter was then used to allow for the real-time fusing of the delayed measurements, and then a final system developed for on-the-fly measurement and compensation of GNSS latency in a RTNS.

  13. Real-time Inversion of Tsunami Source from GNSS Ground Deformation Observations and Tide Gauges.

    Science.gov (United States)

    Arcas, D.; Wei, Y.

    2017-12-01

    Over the last decade, the NOAA Center for Tsunami Research (NCTR) has developed an inversion technique to constrain tsunami sources based on the use of Green's functions in combination with data reported by NOAA's Deep-ocean Assessment and Reporting of Tsunamis (DART®) systems. The system has consistently proven effective in providing highly accurate tsunami forecasts of wave amplitude throughout an entire basin. However, improvement is necessary in two critical areas: reduction of data latency for near-field tsunami predictions and reduction of maintenance cost of the network. Two types of sensors have been proposed as supplementary to the existing network of DART®systems: Global Navigation Satellite System (GNSS) stations and coastal tide gauges. The use GNSS stations to provide autonomous geo-spatial positioning at specific sites during an earthquake has been proposed in recent years to supplement the DART® array in tsunami source inversion. GNSS technology has the potential to provide substantial contributions in the two critical areas of DART® technology where improvement is most necessary. The present study uses GNSS ground displacement observations of the 2011 Tohoku-Oki earthquake in combination with NCTR operational database of Green's functions, to produce a rapid estimate of tsunami source based on GNSS observations alone. The solution is then compared with that obtained via DART® data inversion and the difficulties in obtaining an accurate GNSS-based solution are underlined. The study also identifies the set of conditions required for source inversion from coastal tide-gauges using the degree of nonlinearity of the signal as a primary criteria. We then proceed to identify the conditions and scenarios under which a particular gage could be used to invert a tsunami source.

  14. Integrated GNSS attitude determination and positioning for direct geo-referencing.

    Science.gov (United States)

    Nadarajah, Nandakumaran; Paffenholz, Jens-André; Teunissen, Peter J G

    2014-07-17

    Direct geo-referencing is an efficient methodology for the fast acquisition of 3D spatial data. It requires the fusion of spatial data acquisition sensors with navigation sensors, such as Global Navigation Satellite System (GNSS) receivers. In this contribution, we consider an integrated GNSS navigation system to provide estimates of the position and attitude (orientation) of a 3D laser scanner. The proposed multi-sensor system (MSS) consists of multiple GNSS antennas rigidly mounted on the frame of a rotating laser scanner and a reference GNSS station with known coordinates. Precise GNSS navigation requires the resolution of the carrier phase ambiguities. The proposed method uses the multivariate constrained integer least-squares (MC-LAMBDA) method for the estimation of rotating frame ambiguities and attitude angles. MC-LAMBDA makes use of the known antenna geometry to strengthen the underlying attitude model and, hence, to enhance the reliability of rotating frame ambiguity resolution and attitude determination. The reliable estimation of rotating frame ambiguities is consequently utilized to enhance the relative positioning of the rotating frame with respect to the reference station. This integrated (array-aided) method improves ambiguity resolution, as well as positioning accuracy between the rotating frame and the reference station. Numerical analyses of GNSS data from a real-data campaign confirm the improved performance of the proposed method over the existing method. In particular, the integrated method yields reliable ambiguity resolution and reduces position standard deviation by a factor of about 0:8, matching the theoretical gain of √ 3/4 for two antennas on the rotating frame and a single antenna at the reference station.

  15. CT analysis of 333 cases of congenital malformations of the external and middle ear

    International Nuclear Information System (INIS)

    Zou Xin; Li Qiang; Wang Zhenchang; Xian Junfang; Lan Baosen

    1997-01-01

    To analyze the different CT findings of congenital malformations of the external and middle ear, 333 cases including 404 ears with external and middle ear malformations diagnosed by high resolution CT (HRCT) were analysed according to the location and type of the malformation. In 404 ears, there were 364 ears with atresia of external auditory meatus, 40 ears with stenosis of external auditory meatus, 377 ears with malformation of the ossicles, 382 ears with stenosis of tympanum and 333 ears with anterior position of the mastoid segment of the facial canal. HRCT can show the location and type of external and middle ear malformation and provide valuable information for surgery

  16. The Influences of Online Cultural Capital on Social Tagging Behavior

    Directory of Open Access Journals (Sweden)

    Yi-Fan Chen

    2012-12-01

    Full Text Available This study examines the influences of online cultural capital on social tagging behavior in Delicious.com. The researchers identified three online cultural capital-related variables (understanding of social tagging, understanding of Delicious’ social functionalities, and quantity of tags and bookmarks via factor analysis of a survey dataset and analyzed their influences on tagging motivations (information organization-oriented vs. social-oriented and tagging strategies (object-based tagging vs. situationbased tagging. An existing dataset from a previous survey of Delicious users was used for the analysis. Multiple regression analysis was used to examine the influences of the three variables on tagging motivations and strategies. The study found that understanding of social tagging has a significant positive influence on information organization-oriented tagging; understanding of Delicious’ social functionalities has a significant positive influence on social-oriented tagging. In tagging strategies, understanding of Delicious’ functionalities significantly influenced how strategic respondents are in situation-based tagging. Quantity of tags and bookmarks influenced both types of tagging strategies.

  17. Social Tagging for Personalized Web Search

    Science.gov (United States)

    Biancalana, Claudio

    Social networks and collaborative tagging systems are rapidly gaining popularity as primary means for sorting and sharing data: users tag their bookmarks in order to simplify information dissemination and later lookup. Social Bookmarking services are useful in two important respects: first, they can allow an individual to remember the visited URLs, and second, tags can be made by the community to guide users towards valuable content. In this paper we focus on the latter use: we present a novel approach for personalized web search using query expansion. We further extend the family of well-known co-occurence matrix technique models by using a new way of exploring social tagging services. Our approach shows its strength particularly in the case of disambiguation of word contexts. We show how to design and implement such a system in practice and conduct several experiments. To the best of our knowledge this is the first study centered on using social bookmarking and tagging techniques for personalization of web search and its evaluation in a real-world scenario.

  18. Implementaciones de GNSS RTK en sistemas embebidos autónomos

    OpenAIRE

    Moyano, José Hipólito; Cenci, Karina M.; Ardenghi, Jorge Raúl

    2017-01-01

    Esta línea de investigación tiene como objetivo general analizar y comparar diferentes tecnologías existentes en el área de Global Navigation Satellite Systems (GNSS), buscando destacar las ventajas y desventajas ofrecidas. Como objetivo particular, se buscará realizar el análisis y el desarrollo de GNSS de alta precisión, con dispositivos electrónicos de bajo costo, valiéndose de la biblioteca Real Time Kinematic Library (RTKLIB), la cual implementa algoritmos de Real Time Kinematic (RTK) pa...

  19. Determination of multi-GNSS pseudo-absolute code biases and verification of receiver tracking technology

    Science.gov (United States)

    Villiger, Arturo; Schaer, Stefan; Dach, Rolf; Prange, Lars; Jäggi, Adrian

    2017-04-01

    It is common to handle code biases in the Global Navigation Satellite System (GNSS) data analysis as conventional differential code biases (DCBs): P1-C1, P1-P2, and P2-C2. Due to the increasing number of signals and systems in conjunction with various tracking modes for the different signals (as defined in RINEX3 format), the number of DCBs would increase drastically and the bookkeeping becomes almost unbearable. The Center for Orbit Determination in Europe (CODE) has thus changed its processing scheme to observable-specific signal biases (OSB). This means that for each observation involved all related satellite and receiver biases are considered. The OSB contributions from various ionosphere analyses (geometry-free linear combination) using different observables and frequencies and from clock analyses (ionosphere-free linear combination) are then combined on normal equation level. By this, one consistent set of OSB values per satellite and receiver can be obtained that contains all information needed for GNSS-related processing. This advanced procedure of code bias handling is now also applied to the IGS (International GNSS Service) MGEX (Multi-GNSS Experiment) procedure at CODE. Results for the biases from the legacy IGS solution as well as the CODE MGEX processing (considering GPS, GLONASS, Galileo, BeiDou, and QZSS) are presented. The consistency with the traditional method is confirmed and the new results are discussed regarding the long-term stability. When processing code data, it is essential to know the true observable types in order to correct for the associated biases. CODE has been verifying the receiver tracking technologies for GPS based on estimated DCB multipliers (for the RINEX 2 case). With the change to OSB, the original verification approach was extended to search for the best fitting observable types based on known OSB values. In essence, a multiplier parameter is estimated for each involved GNSS observable type. This implies that we could

  20. GNSS Transpolar Earth Reflectometry exploriNg System (G-TERN): Mission Concept

    DEFF Research Database (Denmark)

    Cardellach, Estel; Wickert, Jens; Baggen, Rens

    2018-01-01

    -temporal resolution crucial characteristics, processes and interactions between sea ice, and other Earth system components in order to advance the understanding and prediction of climate change and its impacts on the environment and society. The objective is articulated through three key questions. 1) In a rapidly...... for 12 simultaneous observations. Unlike currently orbiting GNSS reflectometry missions, the G-TERN uses the full GNSS available bandwidth to improve its ranging measurements. The lifetime would be 2025–2030 or optimally 2025–2035, covering key stages of the transition toward a nearly ice-free Arctic...

  1. Design of GNSS Performance Analysis and Simulation Tools as a Web Portal

    Directory of Open Access Journals (Sweden)

    S. Tadic

    2014-11-01

    Full Text Available This paper considers design of a web-portal for the validation of behavior of GNSS applications in different environments. The tool provides the positioning performance analysis and a comparison to benchmark devices. Web-portal incorporates a 3D synthetic data generator to compute the propagation and the reception of radio-navigation signals in a 3D virtual environment. This radio propagation simulator uses ray-tracing to calculate interactions between the GNSS signal and the local environment. For faster execution on a GPU platform, the simulator uses BVH optimization. The work is verified in field trials and by using reference software.

  2. Endoscopic Ear Surgery: Critical Review of Anatomy and Physiology of Normal and Reconstructive Middle Ear.

    Science.gov (United States)

    Udagatti, Vithal D; Dinesh Kumar, Rajendran

    2016-06-01

    Middle ear anatomy is complex hence it is difficult to study the microscopic vibration of tympanic membrane and ossicles. The basic research has been done in few centres. Our experience is based on clinical data. The lack of quantitative understanding of structural and functional relationship in the mechanical response of the normal and reconstructed middle ear is major factor in poor hearing results after surgery (Merchant et al. in J Laryngol Otol 112:715-731, 1998). The vibration pattern of tympanic membrane changes with different frequencies. It depends upon shape, position and tension of tympanic membrane. Sometimes reconstructed tympanic membrane loses its shape and tension and thus its vibratory response (Pusalkar and Steinbach in Transplants and implants in otology II, 1992). Then what should be the shape, position, tension of the tympanic membrane and the ossicles. In order to have a serviceable hearing, dry and safe ear, there is a necessity of answering all these queries by us.

  3. TOTAL EAR RECONSTRUCTION WITH MONOBLOCK CARTILAGE AND TEMPOROPARIETAL FASCIA

    Directory of Open Access Journals (Sweden)

    Rajendra Prasad

    2015-09-01

    Full Text Available BACKGROUND : Microtia is a congenital ear deformity with incidence of 1:6000. Anotia can be of traumatic origin also. It is one of the greatest challenges to the plastic surgeon to the reconstruct the ear from autologus material . Various developments have occurred in the ear reconstruction from the era of Tanzer. It can be done in a single stage or multiple stages. Single stage ear reconstruction require technical precision, avoids multiple admission of the patient. MATERIAL AND M ETHOD : Between 2007 to 2013 six cases of total ear reconstruction was done in two stage method using autologus coastal cartilage in the department of M.K.C.G medical college by a single surgeon. In the first stage lobule rotation, fabrication of the cartil aginous framework and its implantation were performed. In the second stage elevation of the auricle and formation of tragus was done. All of them underwent stage 1 procedure among them 2 had not turned up for staged 2 procedure. RESULT S: 4 were females and 2 were male. 4 had congenital microtia and two were traumatic amputation of the ear. All had unilateral microtia. The follow up was done for up to 1 year. CONCLUSION: One patient had lost follow up.5 patient had unacceptable ear. Though it is impossible t o reconstruct ear that appear exactly the same as opposite ear , the new ears which were made of correct size and in normal position

  4. Alterations in the Contra lateral Ear in Chronic Otitis Media

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Damghani

    2013-03-01

    Full Text Available Introduction: Chronic otitis media (COM, a persistent and durable inflammation and infection of the middle ear, is a common disorder. Alterations in the contralateral ear in sufferers have been observed in recent years. Because only a few studies have been reported in this area, we performed this study in order to assess alterations in the contralateral ear of patients with COM.   Materials and Methods: Cross-sectional and descriptive methods were used in 100 patients with COM who were selected for surgical treatment and admitted to hospital. An information form was completed for all patients including demographic data, medical history of otoscopy and paraclinical examinations such as pure tone audiometry (PTA, tympanometry, Schuller radiography, and high resolution computed tomography (HRCT. All data were processed using SPSS (version 18 software and descriptive statistical tests.   Results: According to otoscopy, PTA, tympanometry and graphical analysis, 60% of patients experienced disorders of the contralateral ear. Otoscopy analysis showed 54% of patients had a disorder of the contralateral ear, with the most common disorder being perforation of the ear drum. PTA showed a 48% incidence of contralateral ear problems (85% conductive hearing impairment; 12.5% sensorineural hearing impairment; 1.2% mixed. A total of 73.2% of patients with conductive hearing loss had a problem across all frequencies, while half of the patients with sensorineural hearing impairment had problems at frequencies greater than 1000 Hz. According to tympanometry, 38% of patients had problem in the contralateral ear. HRCT and Schuller graphical analyses indicated 31.5% and 36% occurrence of contralateral ear disorders, respectively.   Conclusion:  More than 50% of patients with COM in one ear have a chance of also presenting with the disease in the other ear. Outcomes of this study and previous studies have shown that COM should not be perceived as a disease limited

  5. Passive UHF RFID Tag for Multispectral Assessment

    Directory of Open Access Journals (Sweden)

    Pablo Escobedo

    2016-07-01

    Full Text Available This work presents the design, fabrication, and characterization of a passive printed radiofrequency identification tag in the ultra-high-frequency band with multiple optical sensing capabilities. This tag includes five photodiodes to cover a wide spectral range from near-infrared to visible and ultraviolet spectral regions. The tag antenna and circuit connections have been screen-printed on a flexible polymeric substrate. An ultra-low-power microcontroller-based switch has been included to measure the five magnitudes issuing from the optical sensors, providing a spectral fingerprint of the incident electromagnetic radiation from ultraviolet to infrared, without requiring energy from a battery. The normalization procedure has been designed applying illuminants, and the entire system was tested by measuring cards from a colour chart and sensing fruit ripening.

  6. NoWMex: Continuous GNSS Sites in Northwest Mexico

    Science.gov (United States)

    Gonzalez-Garcia, J. J.; Gonzalez-Ortega, J. A.

    2008-05-01

    Nowadays GPS has become part of daily life activities. In the near future, with the GPS modernization and the use of Glonass and Galileo as a Global Navigation Satellite System will give relative location precision from decimeters to millimeters in near real time applications. In order to realize this, we need a global array of continuously operating GNSS stations built to meet the standards of the geophysical communities and linked with gravimetric local measurements to discern the vertical component of our active Earth. Trying to follow this revolution, CICESE has been working with GPS since 1985. The GPS site CICE was built as an IGS reference station in 1995. Afterward we built 5 more continuous GPS sites in Northwest Mexico with the support of SCIGN. The CGPS NoWMex network is currently made up of six sites: CIC1, SPMX, CORX, GUAX, USMX and YESX (sopac.ucsd.edu). Recently, we implemented an experimental GPS processing lab as part of the Geodesy and Geodynamics Laboratory in the Seismology Department at CICESE. 30 stations are now currently processed from the network Red Geodesica Nacional Activa (RGNA-INEGI), NoWMex, and sites in neighbor countries. Fiducials solutions in ITRF2000 are obtained using GAMIT/GLOBK 10.31 with final igs orbits, every month since 2006. In order to make a contribution to densification of ITRF and support NAREF, SIRGAS and SNARF issues related to scientific and geomatics results; we are looking for internal (Mexican) and external colleagues as well as funding for maintenance and increase the number of CGNSS in NoWMeX including southern Basin and Ranger (Sonora, Chihuahua, Sinaloa and Durango), Gulf of California islands, Peninsular Californias, Nayarit, Jalisco, Colima and the Mexican Pacific islands: Guadalupe (2 more sites), Cedros, Socorro (DORIS site), Clarion and Tres Marias. We must to build more and free available CGNSS sites in and around Mexico to contribute to sea level rise and global change studies.

  7. Comparative Study of the Volumetric Methods Calculation Using GNSS Measurements

    Science.gov (United States)

    Şmuleac, Adrian; Nemeş, Iacob; Alina Creţan, Ioana; Sorina Nemeş, Nicoleta; Şmuleac, Laura

    2017-10-01

    This paper aims to achieve volumetric calculations for different mineral aggregates using different methods of analysis and also comparison of results. To achieve these comparative studies and presentation were chosen two software licensed, namely TopoLT 11.2 and Surfer 13. TopoLT program is a program dedicated to the development of topographic and cadastral plans. 3D terrain model, level courves and calculation of cut and fill volumes, including georeferencing of images. The program Surfer 13 is produced by Golden Software, in 1983 and is active mainly used in various fields such as agriculture, construction, geophysical, geotechnical engineering, GIS, water resources and others. It is also able to achieve GRID terrain model, to achieve the density maps using the method of isolines, volumetric calculations, 3D maps. Also, it can read different file types, including SHP, DXF and XLSX. In these paper it is presented a comparison in terms of achieving volumetric calculations using TopoLT program by two methods: a method where we choose a 3D model both for surface as well as below the top surface and a 3D model in which we choose a 3D terrain model for the bottom surface and another 3D model for the top surface. The comparison of the two variants will be made with data obtained from the realization of volumetric calculations with the program Surfer 13 generating GRID terrain model. The topographical measurements were performed with equipment from Leica GPS 1200 Series. Measurements were made using Romanian position determination system - ROMPOS which ensures accurate positioning of reference and coordinates ETRS through the National Network of GNSS Permanent Stations. GPS data processing was performed with the program Leica Geo Combined Office. For the volumetric calculating the GPS used point are in 1970 stereographic projection system and for the altitude the reference is 1975 the Black Sea projection system.

  8. Phase Transitions of Thermoelectric TAGS-85

    OpenAIRE

    Kumar, Anil; Vermeulen, Paul A.; Kooi, Bart J.; Rao, Jiancun; van Eijck, Lambert; Schwarzmueller, Stefan; Oeckler, Oliver; Blake, Graeme R.

    2017-01-01

    The alloys (GeTe)x(AgSbTe2)100–x, commonly known as TAGS-x, are among the best performing p-type thermoelectric materials for the composition range 80 ≤ x ≤ 90 and in the temperature range 200–500 °C. They adopt a rhombohedrally distorted rocksalt structure at room temperature and are reported to undergo a reversible phase transition to a cubic structure at ∼250 °C. However, we show that, for the optimal x = 85 composition (TAGS-85), both the structural and thermoelectric properties are highl...

  9. Top tagging with deep neural networks [Vidyo

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    Recent literature on deep neural networks for top tagging has focussed on image based techniques or multivariate approaches using high level jet substructure variables. Here, we take a sequential approach to this task by using anordered sequence of energy deposits as training inputs. Unlike previous approaches, this strategy does not result in a loss of information during pixelization or the calculation of high level features. We also propose new preprocessing methods that do not alter key physical quantities such as jet mass. We compare the performance of this approach to standard tagging techniques and present results evaluating the robustness of the neural network to pileup.

  10. A Privacy Model for RFID Tag Ownership Transfer

    Directory of Open Access Journals (Sweden)

    Xingchun Yang

    2017-01-01

    Full Text Available The ownership of RFID tag is often transferred from one owner to another in its life cycle. To address the privacy problem caused by tag ownership transfer, we propose a tag privacy model which captures the adversary’s abilities to get secret information inside readers, to corrupt tags, to authenticate tags, and to observe tag ownership transfer processes. This model gives formal definitions for tag forward privacy and backward privacy and can be used to measure the privacy property of tag ownership transfer scheme. We also present a tag ownership transfer scheme, which is privacy-preserving under the proposed model and satisfies the other common security requirements, in addition to achieving better performance.

  11. Measurement of tag confidence in user generated contents retrieval

    Science.gov (United States)

    Lee, Sihyoung; Min, Hyun-Seok; Lee, Young Bok; Ro, Yong Man

    2009-01-01

    As online image sharing services are becoming popular, the importance of correctly annotated tags is being emphasized for precise search and retrieval. Tags created by user along with user-generated contents (UGC) are often ambiguous due to the fact that some tags are highly subjective and visually unrelated to the image. They cause unwanted results to users when image search engines rely on tags. In this paper, we propose a method of measuring tag confidence so that one can differentiate confidence tags from noisy tags. The proposed tag confidence is measured from visual semantics of the image. To verify the usefulness of the proposed method, experiments were performed with UGC database from social network sites. Experimental results showed that the image retrieval performance with confidence tags was increased.

  12. TagCleaner: Identification and removal of tag sequences from genomic and metagenomic datasets

    Directory of Open Access Journals (Sweden)

    Lim Yan

    2010-06-01

    Full Text Available Abstract Background Sequencing metagenomes that were pre-amplified with primer-based methods requires the removal of the additional tag sequences from the datasets. The sequenced reads can contain deletions or insertions due to sequencing limitations, and the primer sequence may contain ambiguous bases. Furthermore, the tag sequence may be unavailable or incorrectly reported. Because of the potential for downstream inaccuracies introduced by unwanted sequence contaminations, it is important to use reliable tools for pre-processing sequence data. Results TagCleaner is a web application developed to automatically identify and remove known or unknown tag sequences allowing insertions and deletions in the dataset. TagCleaner is designed to filter the trimmed reads for duplicates, short reads, and reads with high rates of ambiguous sequences. An additional screening for and splitting of fragment-to-fragment concatenations that gave rise to artificial concatenated sequences can increase the quality of the dataset. Users may modify the different filter parameters according to their own preferences. Conclusions TagCleaner is a publicly available web application that is able to automatically detect and efficiently remove tag sequences from metagenomic datasets. It is easily configurable and provides a user-friendly interface. The interactive web interface facilitates export functionality for subsequent data processing, and is available at http://edwards.sdsu.edu/tagcleaner.

  13. Photon-tagged and B-meson-tagged b-jet production at the LHC

    Directory of Open Access Journals (Sweden)

    Jinrui Huang

    2015-11-01

    Full Text Available Tagged jet measurements in high energy hadronic and nuclear reactions provide constraints on the energy and parton flavor origin of the parton shower that recoils against the tagging particle. Such additional insight can be especially beneficial in illuminating the mechanisms of heavy flavor production in proton–proton collisions at the LHC and their modification in the heavy ion environment, which are not fully understood. With this motivation, we present theoretical results for isolated-photon-tagged and B-meson-tagged b-jet production at sNN=5.1 TeV for comparison to the upcoming lead–lead data. We find that photon-tagged b-jets exhibit smaller momentum imbalance shift in nuclear matter, and correspondingly smaller energy loss, than photon-tagged light flavor jets. Our results show that B-meson tagging is most effective in ensuring that the dominant fraction of recoiling jets originate from prompt b-quarks. Interestingly, in this channel the large suppression of the cross section is not accompanied by a significant momentum imbalance shift.

  14. First Spaceborne GNSS-Reflectometry Observations of Hurricanes From the UK TechDemoSat-1 Mission

    Science.gov (United States)

    Foti, Giuseppe; Gommenginger, Christine; Srokosz, Meric

    2017-12-01

    We present the first examples of Global Navigation Satellite Systems-Reflectometry (GNSS-R) observations of hurricanes using spaceborne data from the UK TechDemoSat-1 (TDS-1) mission. We confirm that GNSS-R signals can detect ocean condition changes in very high near-surface ocean wind associated with hurricanes. TDS-1 GNSS-R reflections were collocated with International Best Track Archive for Climate Stewardship (IBTrACS) hurricane data, MetOp ASCAT A/B scatterometer winds, and two reanalysis products. Clear variations of GNSS-R reflected power (σ0) are observed as reflections travel through hurricanes, in some cases up to and through the eye wall. The GNSS-R reflected power is tentatively inverted to estimate wind speed using the TDS-1 baseline wind retrieval algorithm developed for low to moderate winds. Despite this, TDS-1 GNSS-R winds through the hurricanes show closer agreement with IBTrACS estimates than winds provided by scatterometers and reanalyses. GNSS-R wind profiles show realistic spatial patterns and sharp gradients that are consistent with expected structures around the eye of tropical cyclones.

  15. [Diagnostic value of high-resolution computed tomography imaging in congenital inner ear malformations].

    Science.gov (United States)

    Sun, Xiaowei; Ding, Yuanping; Zhang, Jianji; Chen, Ying; Xu, Anting; Dou, Fenfen; Zhang, Zihe

    2007-02-01

    To observe the inner ear structure with volume rendering (VR) reconstruction and to evaluate the role of high-resolution computed tomography (HRCT) in congenital inner ear malformations. HRCT scanning was performed in 10 patients (20 ears) without ear disease (control group) and 7 patients (11 ears) with inner ear malformations (IEM group) and the original data was processed with VR reconstruction. The inner ear osseous labyrinth structure in the images generated by these techniques was observed respectively in the normal ears and malformation ears. The inner ear osseous labyrinth structure and the relationship was displayed clearly in VR imaging in the control group,meanwhile, characters and degree of malformed structure were also displayed clearly in the IEA group. Of seven patients (11 ears) with congenital inner ear malformations, the axial, MPR and VR images can display the site and degree in 9 ears. VR images were superior to the axial images in displaying the malformations in 2 ears with the small lateral semicircular canal malformations. The malformations included Mondini deformity (7 ears), vestibular and semicircular canal malformations (3 ears), vestibular aqueduct dilate (7 ears, of which 6 ears accompanied by other malformations) , the internal auditory canal malformation (2 ears, all accompanied by other malformations). HRCT can display the normal structure of bone inner ear through high quality VR reconstructions. VR images can also display the site and degree of the malformations three-dimensionally and intuitively. HRCT is valuable in diagnosing the inner ear malformation.

  16. Presbycusis: do we have a third ear?

    Science.gov (United States)

    Reis, Luis Roque; Escada, Pedro

    Age-related hearing changes are the most frequent cause of sensorineural hearing loss in adults. In the literature no studies exist concerning the importance of speechreading in individuals with presbycusis. Equally, no such studies have been carried out with speakers of the Portuguese (Portugal) language. To evaluate whether the intelligibility of words in presbycusis is improved by speechreading, in such a way that looking at the interlocutor's face while he is talking functions like a "third ear", and to determine the statistical relevance of the intelligibility improvement by speechreading. Eleven individuals (22 ears) with bilateral and symmetrical sensorineural hearing loss compatible with presbycusis were evaluated. The subjects were aged between 57 and 82 years, with an average of 70±11.51 years and median of 69.5 years. A complete medical and audiological profile of each patient was created and all patients were submitted to a vocal audiogram, without and with observation of the audiologist's face. A descriptive and analytical statistical analysis was performed (Shapiro-Wilk and t pairs tests) adopting the significance level of 0.05 (5%). We noticed better performance in intelligibility with speechreading. The p-value was zero (ppresbycusis in this study, performed better on spoken word intelligibility when the hearing of those words was associated with speechreading. This phenomenon helps in such a way that observation of the interlocutor's face works like a "third ear". Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  17. An abbreviated history of the ear: from Renaissance to present.

    OpenAIRE

    Hachmeister, Jorge E.

    2003-01-01

    In this article we discuss important discoveries in relation to the anatomy and physiology of the ear from Renaissance to present. Before the Renaissance, there was a paucity of knowledge of the anatomy of the ear, because of the relative inaccessibility of the temporal bone and the general perception that human dissections should not be conducted. It was not until the sixteenth century that the middle ear was described with detail. Further progress would be made between the sixteenth and eig...

  18. A comparative evaluation of three methods used to tag South African ...

    African Journals Online (AJOL)

    Tagging effects and loss rates of 60 Roman Chrysoblephus laticeps tagged with dart tags with barbs (D-tags), T-bar filaments (T-tags) and visible implant fluorescent elastomer (VIFE) tags were investigated. The fish were tagged and monitored in a controlled tank experiment over a period of 198 days. Application technique ...

  19. Autoimmune Inner Ear Disease- A Clinical Viewpoint

    Directory of Open Access Journals (Sweden)

    Amirala Khalessi

    2010-10-01

    Full Text Available Recent developments in medicine have given us a better insight into a group of disorders known as autoimmune diseases. In particular, advances have occurred in our understanding of the Autoimmune Inner Ear Disease (AIED. In this article, the authors review the different postulated theories in the pathogenesis of this disease. The clinical presentation, the available para-clinical diagnostic tools, and the important differential diagnoses will be summarized. The management methods, including steroid therapy, immunosuppressive medications, other biological agents and intra-tympanic injections, will be addressed. Cochlear implantation as a final solution to the advanced stages of the disease, causing total deafness, will also be discussed.

  20. The inner ear produces a natriuretic hormone

    DEFF Research Database (Denmark)

    Qvortrup, K; Rostgaard, J; Holstein-Rathlou, N H

    1996-01-01

    effects on blood pressure, glomerular filtration rate, or lithium clearance. Only a minor kaliuresis was observed. Extracts of dural tissue adjacent to the endolymphatic sacs had no effect. It is concluded that the endolymphatic sac contains as endogenous inhibitor of sodium reabsorption and could......Cytoplasmic granules have been demonstrated in epithelial cells from the endolymphatic sac, an extraosseus part of the inner ear located in the posterior cranial fossa. Intravenously infused extracts from endolymphatic sacs in anesthetized rats elicited a potent natriuresis and diuresis without...