WorldWideScience

Sample records for monitor onboard accelerations

  1. Gas monitoring onboard ISS using FTIR spectroscopy

    Science.gov (United States)

    Gisi, Michael; Stettner, Armin; Seurig, Roland; Honne, Atle; Witt, Johannes; Rebeyre, Pierre

    2017-06-01

    In the confined, enclosed environment of a spacecraft, the air quality must be monitored continuously in order to safeguard the crew's health. For this reason, OHB builds the ANITA2 (Analysing Interferometer for Ambient Air) technology demonstrator for trace gas monitoring onboard the International Space Station (ISS). The measurement principle of ANITA2 is based on the Fourier Transform Infrared (FTIR) technology with dedicated gas analysis software from the Norwegian partner SINTEF. This combination proved to provide high sensitivity, accuracy and precision for parallel measurements of 33 trace gases simultaneously onboard ISS by the precursor instrument ANITA1. The paper gives a technical overview about the opto-mechanical components of ANITA2, such as the interferometer, the reference Laser, the infrared source and the gas cell design and a quick overview about the gas analysis. ANITA2 is very well suited for measuring gas concentrations specifically but not limited to usage onboard spacecraft, as no consumables are required and measurements are performed autonomously. ANITA2 is a programme under the contract of the European Space Agency, and the air quality monitoring system is a stepping stone into the future, as a precursor system for manned exploration missions.

  2. Fault-Tolerant Onboard Monitoring and Decision Support Systems

    DEFF Research Database (Denmark)

    Lajic, Zoran

    The purpose of this research project is to improve current onboard decision support systems. Special focus is on the onboard prediction of the instantaneous sea state. In this project a new approach to increasing the overall reliability of a monitoring and decision support system has been...

  3. Fault-Tolerant Onboard Monitoring and Decision Support Systems

    DEFF Research Database (Denmark)

    Lajic, Zoran

    a crude and simple estimation of the actual sea state (Hs and Tz), information about the longitudinal hull girder loading, seakeeping performance of the ship, and decision support on how to operate the ship within acceptable limits. The system is able to identify critical forthcoming events and to give...... advice regarding speed and course changes to decrease the wave-induced loads. The SeaSense system is based on the combined use of a mathematical model and measurements from a set of sensors. The overall dependability of a shipboard monitoring and decision support system such as the SeaSense system can......The purpose of this research project is to improve current onboard decision support systems. Special focus is on the onboard prediction of the instantaneous sea state. In this project a new approach to increasing the overall reliability of a monitoring and decision support system has been...

  4. Radiation monitoring around accelerator facilities

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Shinichi [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki (Japan)

    2000-07-01

    The present status of a network of radiation monitors (NORM) working at KEK is described in detail. NORM consists of there parts; stand-alone radiation monitors (SARM), local-monitoring stations (STATION) and a central data-handling system (CENTER). NORM has developed to a large-scaled monitoring system in which more than 250 SARMs are under operation for monitoring the radiation fields and radioactivities around accelerators in KEK. (author)

  5. Calibration of the radiation monitor onboard Akebono using Geant4

    Science.gov (United States)

    Asai, Keiko; Takashima, Takeshi; Koi, Tatsumi; Nagai, Tsugunobu

    Natural high-energy electrons and protons (keV-MeV) in the space contaminate the data re-ciprocally. In order to calibrate the energy ranges and to remove data contamination on the radiation monitor (RDM) onboard the Japanese satellite, Akebono (EXOS-D), the detector is investigated using the Geant4 simulation toolkit of computational particle tracing. The semi-polar orbiting Akebono, launched in February 1989, is active now. This satellite has been observed the space environment at altitudes of several thousands km. The RDM instrument onboard Akebono monitors energetic particles in the Earth's radiation belt and gives important data accumulated for about two solar cycles. The data from RDM are for electrons in three energy channels of 0.3 MeV, protons in three energy channels of ¿ 30 MeV, and alpha particles in one energy channels of 15-45 MeV. The energy ranges are however based on information of about 20 years ago so that the data seem to include some errors actuary. In addition, these data include contamination of electrons and protons reciprocally. Actuary it is noticed that the electron data are contaminated by the solar protons but unknown quantitative amount of the contamination. Therefore we need data calibration in order to correct the energy ranges and to remove data contamination. The Geant4 simulation gives information of trajectories of incident and secondary particles whose are interacted with materials. We examine the RDM monitor using the Geant4 simulation. We find from the results that relativistic electrons of MeV behave quite complicatedly because of particle-material interaction in the instrument. The results indicate that efficiencies of detection and contamination are dependent on energy. This study compares the electron data from Akebono RDM with the simultaneous observation of CRRES and tries to lead the values of correction for each of the energy channels.

  6. Monitoring automotive oil degradation: analytical tools and onboard sensing technologies.

    Science.gov (United States)

    Mujahid, Adnan; Dickert, Franz L

    2012-09-01

    Engine oil experiences a number of thermal and oxidative phases that yield acidic products in the matrix consequently leading to degradation of the base oil. Generally, oil oxidation is a complex process and difficult to elucidate; however, the degradation pathways can be defined for almost every type of oil because they mainly depend on the mechanical status and operating conditions. The exact time of oil change is nonetheless difficult to predict, but it is of great interest from an economic and ecological point of view. In order to make a quick and accurate decision about oil changes, onboard assessment of oil quality is highly desirable. For this purpose, a variety of physical and chemical sensors have been proposed along with spectroscopic strategies. We present a critical review of all these approaches and of recent developments to analyze the exact lifetime of automotive engine oil. Apart from their potential for degradation monitoring, their limitations and future perspectives have also been investigated.

  7. Aircrew exposure onboard a Czech airlines aircraft, individual monitoring of aircrew

    Energy Technology Data Exchange (ETDEWEB)

    Ploc, O.; Spurny, F.; Turek, K. [Nuclear Physics Institute AS CR, Dept. of Radiation Dosimetry, Prague (Czech Republic); Ploc, O. [Czech Technical Univ., Dept. of Dosimetry and Application of Ionizing Radiation, Prague (Czech Republic)

    2006-07-01

    The contribution presents new results related to the aircraft crew exposure onboard aircraft of Czech air companies. First the results of long term monitoring onboard of an aircraft of Czech Airlines are presented. The monitoring has been performed in the period May - December 2005, more than 500 individual flights have been followed. M.D.U.-Liulin Si-diode based spectrometer was used, together with thermoluminescent and track detectors. Total effective dose was about 12 mSv, the results obtained with dosimeters mentioned are analyzed and compared with the results of calculation performed with C.A.R.I. and E.P.C.A.R.D. codes. Individual monitoring of air crew members has been started in the Czech Republic since 1998 year. The results obtained during few last years are presented, general tendencies of aircraft crew onboard exposure of Czech air companies are outlined. (authors)

  8. Onboard monitoring of fatigue damage rates in the hull girder

    DEFF Research Database (Denmark)

    Nielsen, Ulrik Dam; Jensen, Jørgen Juncher; Pedersen, Preben Terndrup

    2011-01-01

    Most new advanced ships have extensive data collection systems to be used for continuous monitoring of engine and hull performance, for voyage performance evaluation etc. Such systems could be expanded to include also procedures for stress monitoring and for decision support, where the most...

  9. SE83-9 'Chix in Space' student experimenter monitors STS-29 onboard activity

    Science.gov (United States)

    1989-01-01

    Student experimenter John C. Vellinger watches monitor in the JSC Mission Control Center (MCC) Bldg 30 Customer Support Room (CSR) during the STS-29 mission. Crewmembers are working with his Student Experiment (SE) 83-9 Chicken Embryo Development in Space or 'Chix in Space' onboard Discovery, Orbiter Vehicle (OV) 103. The student's sponsor is Kentucky Fried Chicken (KFC).

  10. ONBOARD MONITORING OF ENGINE OIL RESOURCE WORKING-OUT RATE IN WHEELED AND CATERPILLAR MACHINES

    Directory of Open Access Journals (Sweden)

    Yu. D. Karpievich

    2014-01-01

    Full Text Available An engine oil is capable reliably and longtime to perform specified functions only in the case when its properties correspond to those thermal, mechanical and chemical impacts to which the oil is subjected in the engine. Compatibility of the engine design, its uprate and oil properties is one of the main conditions for provision of high operational reliability. Type and properties of fuel, quality of an engine oil, engine type, its design, its health, its operational regime and conditions and a number of other factors influence on intensity of oil contamination in the operated engine. Oil quality is deteriorated due to accumulation of incomplete combustion products in it and this process is associated with the engine's health. This leads to reduction of viscosity, deterioration of lubrication ability, troubles in fluid friction mode. Combustion products have rather high amount of aggressive corrosive oxides.Service-life of engine oil prior to its change is determined not only by automobile mileage or tractor operating time but also by the period of time within which this work has been carried out. Corrosion processes are speeding up, protective processes are worsening, oil ageing is accelerating when vehicles have short daily and small mileages. So it is necessary to change oil at least annually.A new method for onboard monitoring of engine oil resource working-out rate in wheeled and caterpillar machines has been developed in the paper. Usage of fuel expended volume by engine while determining engine oil resource working-out rate makes it possible timely to assess a residual resource of the engine oil and also predict the date of its change at any operational period of wheeled and caterpillar machines.

  11. Sensor network architecture for intelligent high-speed train on-board monitoring

    Institute of Scientific and Technical Information of China (English)

    Xiao-fan WU; Chun CHEN; Jia-jun BU; Gang CHEN

    2011-01-01

    The China's high-speed railway is experiencing a rapid growth.Its operating mileage and the number of operating trains will exceed 45000 km and 1500 trains by 2015,respectively.During the long range and constant high-speed operation,the high-speed trains have extremely complex and varied work conditions.Such a situation creates a huge demand for high-speed train on-board monitoring.In this paper,architecture for high-speed train on-board monitoring sensor network is proposed.This architecture is designed to achieve the goals of reliable sensing,scalable data transporting,and easy management.The three design goals are realized separately.The reliable sensing is achieved by deploying redundant sensor nodes in the same components.Then a hierarchal transporting scheme is involved to meet the second goal.Finally,an electronic-tag based addressing method is introduced to solve the management problem.

  12. Theoretical aspects of implementation of kilovoltage cone-beam CT onboard linear accelerator for image-guided radiotherapy.

    Science.gov (United States)

    Rodríguez Cordón, Marta; Ferrer Albiach, Carlos

    2009-08-01

    The main objective of image-guided radiation therapy (IGRT) equipment is to reduce and correct inherent errors in external radiotherapy processes. At the present time, there are different IGRT systems available, but here we will refer exclusively to the kilovoltage cone-beam CT onboard linear accelerator (CBkVCT) and the different aspects that, from a clinical point of view, should be taken into consideration before the implementation of this equipment.

  13. Artificial Neural Networks Applications: from Aircraft Design Optimization to Orbiting Spacecraft On-board Environment Monitoring

    Science.gov (United States)

    Jules, Kenol; Lin, Paul P.

    2002-01-01

    This paper reviews some of the recent applications of artificial neural networks taken from various works performed by the authors over the last four years at the NASA Glenn Research Center. This paper focuses mainly on two areas. First, artificial neural networks application in design and optimization of aircraft/engine propulsion systems to shorten the overall design cycle. Out of that specific application, a generic design tool was developed, which can be used for most design optimization process. Second, artificial neural networks application in monitoring the microgravity quality onboard the International Space Station, using on-board accelerometers for data acquisition. These two different applications are reviewed in this paper to show the broad applicability of artificial intelligence in various disciplines. The intent of this paper is not to give in-depth details of these two applications, but to show the need to combine different artificial intelligence techniques or algorithms in order to design an optimized or versatile system.

  14. Respiratory monitoring with an acceleration sensor

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Tomohiro; Takegawa, Hideki; Ageishi, Tatsuya; Takashina, Masaaki; Numasaki, Hodaka; Matsumoto, Masao; Teshima, Teruki, E-mail: teshima@sahs.med.osaka-u.ac.jp [Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Yamadaoka 1-7, Suita-shi, Osaka 565-0871 (Japan)

    2011-10-07

    Respiratory gating radiotherapy is used to irradiate a local area and to reduce normal tissue toxicity. There are certain methods for the detection of tumor motions, for example, using internal markers or an external respiration signal. However, because some of these respiratory monitoring systems require special or expensive equipment, respiratory monitoring can usually be performed only in limited facilities. In this study, the feasibility of using an acceleration sensor for respiratory monitoring was evaluated. The respiratory motion was represented by means of a platform and measured five times with the iPod touch (registered) at 3, 4 and 5 s periods of five breathing cycles. For these three periods of the reference waveform, the absolute means {+-} standard deviation (SD) of displacement were 0.45 {+-} 0.34 mm, 0.33 {+-} 0.24 mm and 0.31 {+-} 0.23 mm, respectively. On the other hand, the corresponding absolute means {+-} SD for the periods were 0.04 {+-} 0.09 s, 0.04 {+-} 0.02 s and 0.06 {+-} 0.04 s. The accuracy of respiratory monitoring using the acceleration sensor was satisfactory in terms of the absolute means {+-} SD. Using the iPod touch (registered) for respiratory monitoring does not need special equipment and makes respiratory monitoring easier. For these reasons, this system is a viable alternative to other respiratory monitoring systems.

  15. A novel approach for navigational guidance of ships using onboard monitoring systems

    DEFF Research Database (Denmark)

    Nielsen, Ulrik Dam; Jensen, Jørgen Juncher

    2011-01-01

    A novel approach and conceptual ideas are outlined for risk-based navigational guidance of ships using decision support systems in combination with onboard, in-service monitoring systems. The guidance has as the main objective to advise on speed and/or course changes; in particular with focus...... on ship operations in rough weather. It is strived for to make use of a probabilistic framework considering the mathematical procedures that the guidance relies upon. The paper presents a novel conceptwhich has the possibility to increase the reliability of the provided guidance, although information...

  16. Fermilab accelerator control system: Analog monitoring facilities

    Energy Technology Data Exchange (ETDEWEB)

    Seino, K.; Anderson, L.; Smedinghoff, J.

    1987-10-01

    Thousands of analog signals are monitored in different areas of the Fermilab accelerator complex. For general purposes, analog signals are sent over coaxial or twinaxial cables with varying lengths, collected at fan-in boxes and digitized with 12 bit multiplexed ADCs. For higher resolution requirements, analog signals are digitized at sources and are serially sent to the control system. This paper surveys ADC subsystems that are used with the accelerator control systems and discusses practical problems and solutions, and it describes how analog data are presented on the console system.

  17. Wakefield monitor development for CLIC accelerating structure

    CERN Document Server

    Peauger, F; Girardot, P; Andersson, A; Riddone, G; Samoshkin, A; Solodko, A; Zennaro, R; Ruber, R

    2010-01-01

    Abstract To achieve high luminosity in CLIC, the accelerating structures must be aligned to an accuracy of 5 μm with respect to the beam trajectory. Position detectors called Wakefield Monitors (WFM) are integrated to the structure for a beam based alignment. This paper describes the requirements of such monitors. Detailed RF design and electromagnetic simulations of the WFM itself are presented. In particular, time domain computations are performed and an evaluation of the resolution is done for two higher order modes at 18 and 24 GHz. The mechanical design of a prototype accelerating structure with WFM is also presented as well as the fabrication status of three complete structures. The objective is to implement two of them in CTF3 at CERN for a feasibility demonstration with beam and high power rf.

  18. An Integrated Architecture for On-Board Aircraft Engine Performance Trend Monitoring and Gas Path Fault Diagnostics

    Science.gov (United States)

    Simon, Donald L.

    2010-01-01

    Aircraft engine performance trend monitoring and gas path fault diagnostics are closely related technologies that assist operators in managing the health of their gas turbine engine assets. Trend monitoring is the process of monitoring the gradual performance change that an aircraft engine will naturally incur over time due to turbomachinery deterioration, while gas path diagnostics is the process of detecting and isolating the occurrence of any faults impacting engine flow-path performance. Today, performance trend monitoring and gas path fault diagnostic functions are performed by a combination of on-board and off-board strategies. On-board engine control computers contain logic that monitors for anomalous engine operation in real-time. Off-board ground stations are used to conduct fleet-wide engine trend monitoring and fault diagnostics based on data collected from each engine each flight. Continuing advances in avionics are enabling the migration of portions of the ground-based functionality on-board, giving rise to more sophisticated on-board engine health management capabilities. This paper reviews the conventional engine performance trend monitoring and gas path fault diagnostic architecture commonly applied today, and presents a proposed enhanced on-board architecture for future applications. The enhanced architecture gains real-time access to an expanded quantity of engine parameters, and provides advanced on-board model-based estimation capabilities. The benefits of the enhanced architecture include the real-time continuous monitoring of engine health, the early diagnosis of fault conditions, and the estimation of unmeasured engine performance parameters. A future vision to advance the enhanced architecture is also presented and discussed

  19. Early In-orbit Performance of Scanning Sky Monitor Onboard AstroSat

    Indian Academy of Sciences (India)

    M. C. Ramadevi; B. T. Ravishankar; N. Sitaramamurthy; G. Meena; Brajpal Singh; Anand Jain; Reena Yadav; Anil Agarwal; V. Chandra Babu; Kumar; Ankur Kushwaha; S. Vaishali; Nirmal Kumar Iyer; Anuj Nandi; Girish V.; Vivek Kumar Agarwal; S. Seetha; Dipankar Bhattacharya; K. Balaji; Manoj Kumar; Prashanth Kulshresta

    2017-06-01

    We report the in-orbit performance of Scanning Sky Monitor (SSM) onboard AstroSat. The SSM operates in the energy range 2.5 to 10 keV and scans the sky to detect and locate transient X-ray sources. This information of any interesting phenomenon in the X-ray sky as observed by SSM is provided to the astronomical community for follow-up observations. Following the launch of AstroSat on 28th September, 2015, SSM was commissioned on October 12th, 2015. The first power ON of the instrument was with the standard X-ray source, Crab in the field-of-view. The first orbit data revealed the basic expected performance of one of the detectors of SSM, SSM1. Following this in the subsequent orbits, the other detectors were also powered ON to find them perform in good health. Quick checks of the data from the first few orbits revealed that the instrument performed with the expected angular resolution of 12’ × 2.5∘ and effective area in the energy range of interest. This paper discusses the instrument aspects along with few on-board results immediately after power ON.

  20. ON-BOARD MONITORING OF TECHNICAL STATE FOR POWER UNITS OF WHEELED AND TRACKED VEHICLES

    Directory of Open Access Journals (Sweden)

    Yu. D. Karpievich

    2016-01-01

    Full Text Available The paper considers new methodologies pertaining to on-board diagnosis of wear-out rate for friction linings of a clutch driven disk and friction discs of a hydraulic press clutch of transmission gear boxes which are based on physical process that uses friction work as an integrated indicator. A new methodology in determination of life-span rate for engine oil has been developed in the paper. The paper presents block schematic diagrams for on-board monitoring of technical state for power units of wheeled and tracked vehicles. Usage of friction work as an integrated indicator for determination of wear-out rate for friction linings of clutch driven disk and friction discs of a haydraulic press clutch makes it possible timely at any operational period of wheeled and tracked vehicles to determine their residual operation life and forecast their replacement.While taking volume of the used fuel for determination of engine oil life-span rate it permits quickly and effectively at any operational period of wheeled and tracked vehicles to determine residual useful life of the engine oil and also forecast its replacement.

  1. Long-term monitoring of the onboard aircraft exposure level with a Si-diode based spectrometer.

    Science.gov (United States)

    Spurny, F; Dachev, Ts

    2003-01-01

    The radiation fields onboard aircraft are complex (EURADOS, 1996), and several methods are used to characterise them for radiation protection. We have tested a spectrometer based on Si-diode at different sources and accelerator facilities. The energy deposited in the diode is analysed to estimate the contribution of different radiations to dosimetry quantities. The spectrum of energy deposition events onboard aircraft is similar to that registered in the CERN high-energy reference field. We used this similarity to determine the correction factors to appreciate radiation protection quantities from the results of onboard measurements. During 2001-2002, the spectrometer was used to acquire measurements onboard commercial aircraft during five long-term exposures. All necessary flight parameters were acquired; thus permitting calculations of the onboard effective dose and/or ambient dose equivalent by means of both the CARI 6 and the EPCARD codes and comparison with the results of the measurements. It was found that the apparent ambient dose equivalent values from measured data are in reasonable agreement with the results of calculations. Quantitative analysis of this agreement as a function of flight parameters (geomagnetic position, solar activity variations, etc.) is presented. During one flight, an important solar event (GLE 60 on 15 April 2001) was recorded by the spectrometer. In some other cases the measurements during a Forbush decreases were acquired. These extremes were well registered by the equipment and the data obtained are analyzed.

  2. Earth's gravity field modelling based on satellite accelerations derived from onboard GPS phase measurements

    Science.gov (United States)

    Guo, X.; Ditmar, P.; Zhao, Q.; Klees, R.; Farahani, H. H.

    2017-09-01

    GPS data collected by satellite gravity missions can be used for extracting the long-wavelength part of the Earth's gravity field. We propose a new data processing method which makes use of the `average acceleration' approach to gravity field modelling. In this method, satellite accelerations are directly derived from GPS carrier phase measurements with an epoch-differenced scheme. As a result, no ambiguity solutions are needed and the systematic errors that do not change much from epoch to epoch are largely eliminated. The GPS data collected by the Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) satellite mission are used to demonstrate the added value of the proposed method. An analysis of the residual accelerations shows that accelerations derived in this way are more precise, with noise being reduced by about 20 and 5% at the cross-track component and the other two components, respectively, as compared to those based on kinematic orbits. The accelerations obtained in this way allow the recovery of the gravity field to a slightly higher maximum degree compared to the solution based on kinematic orbits. Furthermore, the gravity field solution has an overall better performance. Errors in spherical harmonic coefficients are smaller, especially at low degrees. The cumulative geoid height error is reduced by about 15 and 5% up to degree 50 and 150, respectively. An analysis in the spatial domain shows that large errors along the geomagnetic equator, which are caused by a high electron density coupled with large short-term variations, are substantially reduced. Finally, the new method allows for a better observation of mass transport signals. In particular, sufficiently realistic signatures of regional mass anomalies in North America and south-west Africa are obtained.

  3. Earth's gravity field modelling based on satellite accelerations derived from onboard GPS phase measurements

    Science.gov (United States)

    Guo, X.; Ditmar, P.; Zhao, Q.; Klees, R.; Farahani, H. H.

    2017-02-01

    GPS data collected by satellite gravity missions can be used for extracting the long-wavelength part of the Earth's gravity field. We propose a new data processing method which makes use of the `average acceleration' approach to gravity field modelling. In this method, satellite accelerations are directly derived from GPS carrier phase measurements with an epoch-differenced scheme. As a result, no ambiguity solutions are needed and the systematic errors that do not change much from epoch to epoch are largely eliminated. The GPS data collected by the Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) satellite mission are used to demonstrate the added value of the proposed method. An analysis of the residual accelerations shows that accelerations derived in this way are more precise, with noise being reduced by about 20 and 5% at the cross-track component and the other two components, respectively, as compared to those based on kinematic orbits. The accelerations obtained in this way allow the recovery of the gravity field to a slightly higher maximum degree compared to the solution based on kinematic orbits. Furthermore, the gravity field solution has an overall better performance. Errors in spherical harmonic coefficients are smaller, especially at low degrees. The cumulative geoid height error is reduced by about 15 and 5% up to degree 50 and 150, respectively. An analysis in the spatial domain shows that large errors along the geomagnetic equator, which are caused by a high electron density coupled with large short-term variations, are substantially reduced. Finally, the new method allows for a better observation of mass transport signals. In particular, sufficiently realistic signatures of regional mass anomalies in North America and south-west Africa are obtained.

  4. POD improvements of GALILEO satellites through the measurement of their non-gravitational accelerations by means of an onboard accelerometer

    Science.gov (United States)

    Peron, Roberto; Lucchesi, David M.; Santoli, Francesco; Iafolla, Valerio; Fiorenza, Emiliano; Lefevre, Carlo; Lucente, Marco; Magnafico, Carmelo; Kalarus, Maciej; Zielinski, Janusz

    2016-04-01

    The Precise Orbit Determination (POD) of the satellites of the Global Navigation Satellite Systems (GNSS) represents the basic prerequisite in order to provide refined ephemerides for their orbit, aimed at providing a precise and accurate positioning on the Earth. An important factor that impacts negatively in the POD of these satellites is the limited modeling of the accelerations produced by the non-gravitational accelerations. These, indeed, are subtle and generally complex to model properly, especially in the case of a complex in shape spacecraft, with solar panels and antennae for microwave link and the mutual shadowing effects among the many surfaces involved. We have to notice that their modeling has an important impact in the determination of a number of geophysical parameters of interest, such as stations coordinates, Earth's geocenter and orientation parameters. In the case of GNSS satellites, the main NGP acceleration is the one produced by the direct solar radiation pressure, with non-negligible contributions due to Earth's albedo, thermal effects and power radiated by the antennae. The models developed so far for these perturbative effects have shown many limits, as pointed out in the literature. Currently, the models developed for the NGPs are mainly based on empirical blind models (with the goal of absorb unknowns quantities) and more recently with the use of wing-box models, that try to provide a finite-elements approach to the modeling. The European Space Agency (ESA) - in the context of the development of the GALILEO constellation, and especially in view of the next generation of GALILEO spacecraft - besides being interested in possible improvements of the NGPs models, is also envisaging the use of an onboard accelerometer to directly measure them in order to improve the POD of each spacecraft of the constellation. We have been involved in this study by means of a proposal to ESA denominated GALileo and ACcelerometry (GALAC) led by the Space

  5. Potential of the TROPOspheric Monitoring Instrument (TROPOMI onboard the Sentinel-5 Precursor for the monitoring of terrestrial chlorophyll fluorescence

    Directory of Open Access Journals (Sweden)

    L. Guanter

    2014-12-01

    photosynthetic functioning of terrestrial ecosystems. The feasibility of SIF retrievals from spaceborne atmospheric spectrometers has been demonstrated by a number of studies in the last years. In this work, we investigate the potential of the upcoming TROPOspheric Monitoring Instrument (TROPOMI onboard the Sentinel-5 Precursor satellite mission for SIF retrieval. TROPOMI will sample the 675–775 nm spectral window with a spectral resolution of 0.5 nm and a pixel size of 7 km × 7 km. We use an extensive set of simulated TROPOMI data in order to assess the uncertainty of single SIF retrievals and subsequent spatio-temporal composites. Our results illustrate the enormous improvement in SIF monitoring achievable with TROPOMI with respect to comparable spectrometers currently in-flight, such as the Global Ozone Monitoring Experiment-2 (GOME-2 instrument. We find that TROPOMI can reduce global uncertainties in SIF mapping by more than a factor 2 with respect to GOME-2, which comes together with an about 5-fold improvement in spatial sampling. Finally, we discuss the potential of TROPOMI to accurately map other important vegetation parameters, such as leaf photosynthetic pigments and proxies for canopy structure, which will complement SIF retrievals for a self-contained description of vegetation condition and functioning.

  6. Accelerated Aging Experiments for Capacitor Health Monitoring and Prognostics

    Data.gov (United States)

    National Aeronautics and Space Administration — This paper discusses experimental setups for health monitoring and prognostics of electrolytic capacitors under nominal operation and accelerated aging conditions....

  7. An Interference-Aware Transmission Power Control Scheme for Vehicular On-board Monitoring Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Jiajun Bu

    2012-09-01

    Full Text Available Wireless sensor network (WSN has been used widely in vehicular on-board monitoring area. In the scenario of vehicular monitoring, the wireless sensor nodes share similar electromagnet environment. This phenomenon can be used by the sending node to infer the receiver’s noise level. Moreover, the sender can decide the transmitting power accordingly. In this paper, we proposed a interference-aware approaching to control the transmission power of nodes in a vehicular on-board monitoring WSN. By making use of the relationship of noise level on the sender side and the receiver side, the sender node can decide the necessary transmitting power to send a packet successfully. Because the packets are sent at high enough transmission power, the Packet Reception Rate (PRR is improved. At the same time, the network latency caused by communication failure is reduced.

  8. Reactivity Monitoring of Accelerator-Driven Nuclear Reactor Systems

    NARCIS (Netherlands)

    Uyttenhove, W.

    2016-01-01

    This thesis provides a methodology and set-up of a reactivity monitoring tool for Accelerator-Driven Systems (ADS). The reactivity monitoring tool should guarantee the operation of an ADS at a safe margin from criticality. Robustness is assured in different aspects of the monitoring tool: the choice

  9. Reactivity Monitoring of Accelerator-Driven Nuclear Reactor Systems

    NARCIS (Netherlands)

    Uyttenhove, W.

    2016-01-01

    This thesis provides a methodology and set-up of a reactivity monitoring tool for Accelerator-Driven Systems (ADS). The reactivity monitoring tool should guarantee the operation of an ADS at a safe margin from criticality. Robustness is assured in different aspects of the monitoring tool: the choice

  10. Beam Position Monitoring in the CSU Accelerator Facility

    Science.gov (United States)

    Einstein, Joshua; Vankeuren, Max; Watras, Stephen

    2014-03-01

    A Beam Position Monitoring (BPM) system is an integral part of an accelerator beamline, and modern accelerators can take advantage of newer technologies and designs when creating a BPM system. The Colorado State University (CSU) Accelerator Facility will include four stripline detectors mounted around the beamline, a low-noise analog front-end, and digitization and interface circuitry. The design will support a sampling rate greater than 10 Hz and sub-100 μm accuracy.

  11. Assessment of polycarbonate filter in a molecular analytical system for the microbiological quality monitoring of recycled waters onboard ISS.

    Science.gov (United States)

    Bechy-Loizeau, Anne-Laure; Flandrois, Jean-Pierre; Abaibou, Hafid

    2015-07-01

    On the ISS, as on Earth, water is an essential element for life and its quality control on a regular basis allows to ensure the health of the crew and the integrity of equipment. Currently, microbial water analysis onboard ISS still relies on the traditional culture-based microbiology methods. Molecular methods based on the amplification of nucleic acids for microbiological analysis of water quality show enormous potential and are considered as the best alternative to culture-based methods. For this reason, the Midass, a fully integrated and automated prototype was designed conjointly by ESA and bioMérieux for a rapid monitoring of the microbiological quality of air. The prototype allows air sampling, sample processing and the amplification/detection of nucleic acids. We describe herein the proof of principle of an analytical approach based on molecular biology that could fulfill the ESA's need for a rapid monitoring of the microbiological quality of recycled water onboard ISS. Both concentration and recovery of microorganisms are the main critical steps when the microfiltration technology is used for water analysis. Among filters recommended standards for monitoring the microbiological quality of the water, the polycarbonate filter was fully in line with the requirements of the ISO 7704-1985 standard in terms of efficacy of capture and recovery of bacteria. Moreover, this filter does not retain nucleic acids on the surface and has no inhibitory effect on their downstream processing steps such as purification and amplification/detection. Although the Midass system was designed for the treatment of air samples, the first results on the integration of PC filters were encouraging. Nevertheless, system modifications are needed to better adapt the Midass system for the monitoring of the microbiological water quality.

  12. Automatic classification of urban traffic noise onboard an acoustic monitoring system

    NARCIS (Netherlands)

    Wessels, P.W.; Zon, A.T. van; Basten, T.G.H.

    2013-01-01

    Recent developments in acoustic monitoring systems make it possible to measure complex noise situations, like urban traffic noise, continuously. Monitoring provides more insight in the noise situation, from which more specific and (cost) effective measures can be taken. Monitoring also allows direct

  13. Automatic classification of urban traffic noise onboard an acoustic monitoring system

    NARCIS (Netherlands)

    Wessels, P.W.; Zon, A.T. van; Basten, T.G.H.

    2013-01-01

    Recent developments in acoustic monitoring systems make it possible to measure complex noise situations, like urban traffic noise, continuously. Monitoring provides more insight in the noise situation, from which more specific and (cost) effective measures can be taken. Monitoring also allows direct

  14. On-Board Computing for Structural Health Monitoring with Smart Wireless Sensors by Modal Identification Using Hilbert-Huang Transform

    Directory of Open Access Journals (Sweden)

    Ning Wu

    2013-01-01

    Full Text Available Smart wireless sensors have been recognized as a promising technology to overcome many inherent difficulties and limitations associated with traditional wired structural health monitoring (SHM systems. Despite the advances in smart sensor technologies, on-board computing capability of smart sensors has been considered as one of the most difficult challenges in the application of the smart sensors in SHM. Taking the advantage of recent developments in microprocessor which provides powerful on-board computing functionality for smart sensors, this paper presents a new decentralized data processing approach for modal identification using the Hilbert-Huang transform (HHT algorithm, which is based on signal decomposition technique. It is shown that this method is suitable for implementation in the intrinsically distributed computing environment found in wireless smart sensor networks (WSSNs. The HHT-based decentralized data processing is, then, programmed and implemented on the Crossbow IRIS mote sensor platform. The effectiveness of the proposed techniques is demonstrated through a set of numerical studies and experimental validations on an in-house cable-stayed bridge model in terms of the accuracy of identified dynamic properties.

  15. Automated Miniaturized Instrument for Space Biology Applications and the Monitoring of the Astronauts Health Onboard the ISS

    Science.gov (United States)

    Karouia, Fathi; Peyvan, Kia; Danley, David; Ricco, Antonio J.; Santos, Orlando; Pohorille, Andrew

    2011-01-01

    Human space travelers experience a unique environment that affects homeostasis and physiologic adaptation. The spacecraft environment subjects the traveler to noise, chemical and microbiological contaminants, increased radiation, and variable gravity forces. As humans prepare for long-duration missions to the International Space Station (ISS) and beyond, effective measures must be developed, verified and implemented to ensure mission success. Limited biomedical quantitative capabilities are currently available onboard the ISS. Therefore, the development of versatile instruments to perform space biological analysis and to monitor astronauts' health is needed. We are developing a fully automated, miniaturized system for measuring gene expression on small spacecraft in order to better understand the influence of the space environment on biological systems. This low-cost, low-power, multi-purpose instrument represents a major scientific and technological advancement by providing data on cellular metabolism and regulation. The current system will support growth of microorganisms, extract and purify the RNA, hybridize it to the array, read the expression levels of a large number of genes by microarray analysis, and transmit the measurements to Earth. The system will help discover how bacteria develop resistance to antibiotics and how pathogenic bacteria sometimes increase their virulence in space, facilitating the development of adequate countermeasures to decrease risks associated with human spaceflight. The current stand-alone technology could be used as an integrated platform onboard the ISS to perform similar genetic analyses on any biological systems from the tree of life. Additionally, with some modification the system could be implemented to perform real-time in-situ microbial monitoring of the ISS environment (air, surface and water samples) and the astronaut's microbiome using 16SrRNA microarray technology. Furthermore, the current system can be enhanced

  16. Wakefield Monitor Experiments with X-Band Accelerating Structures

    CERN Document Server

    Lillestøl, Reidar; Corsini, Roberto; Döbert, Steffen; Farabolini, Wilfrid; Malina, Lukas; Pfingstner, Juergen; Wuensch, Walter

    2015-01-01

    The accelerating structures for CLIC must be aligned with a precision of a few um with respect to the beam trajectory in order to mitigate emittance growth due to transverse wake fields. We report on first results from wake field monitor tests in an X-band structure, with a probe beam at the CLIC Test Facility. The monitors are currently installed in the CLIC Two-Beam Module. In order to fully demonstrate the feasibility of using wakefield monitors for CLIC, the precision of the monitors must be verified using a probe beam while simultaneously filling the structure with high power rf used to drive the accelerating mode. We outline plans to perform such a demonstration in the CLIC Test Facility.

  17. CCD based beam loss monitor for ion accelerators

    Science.gov (United States)

    Belousov, A.; Mustafin, E.; Ensinger, W.

    2014-04-01

    Beam loss monitoring is an important aspect of proper accelerator functioning. There is a variety of existing solutions, but each has its own disadvantages, e.g. unsuitable dynamic range or time resolution, high cost, or short lifetime. Therefore, new options are looked for. This paper shows a method of application of a charge-coupled device (CCD) video camera as a beam loss monitor (BLM) for ion beam accelerators. The system was tested with a 500 MeV/u N+7 ion beam interacting with an aluminum target. The algorithms of camera signal processing with LabView based code and beam loss measurement are explained. Limits of applicability of this monitor system are discussed.

  18. Monitoring the Health and Safety of the ACIS Instrument On-Board the Chandra X-ray Observatory

    CERN Document Server

    Virani, S N; De Pasquale, J M; Plucinsky, P P; Virani, Shanil N.; Ford, Peter G.; Pasquale, Joseph M. De; Plucinsky, Paul P.

    2002-01-01

    The Chandra X-ray Observatory (CXO), NASA's latest ``Great Observatory'', was launched on July 23, 1999 and reached its final orbit on August 7, 1999. The CXO is in a highly elliptical orbit, approximately 140,000 km x 10,000 km, and has a period of approximately 63.5 hours (~2.65 days). Communication with the CXO nominally consists of 1-hour contacts spaced 8-hours apart. Thus, once a communication link has been established, it is very important that the health and safety status of the scientific instruments as well as the Observatory itself be determined as quickly as possible. In this paper, we focus exclusively on the automated health and safety monitoring scripts developed for the Advanced CCD Imaging Spectrometer (ACIS) to use during those 1-hour contacts. ACIS is one of the two focal plane instruments on-board the CXO. We present an overview of the real-time ACIS Engineering Data Web Page and the alert schemes developed for monitoring the instrument status during each communication contact. A suite of ...

  19. In-Flight Performance of the Water Vapor Monitor Onboard the Sofia Observatory

    Science.gov (United States)

    Roellig, Thomas L.; Yuen, Lunming; Sisson, David; Hang, Richard

    2012-01-01

    NASA's Stratospheric Observatory for Infrared Astronomy (SOFIA) airborne observatory flies in a modified B747-SP aircraft in the lower stratosphere above more than 99.9% of the Earth's water vapor. As low as this residual water vapor is, it will still affect SOFIA's infrared and sub-millimeter astronomical observations. As a result, a heterodyne instrument has been developed to observe the strength and shape of the 1830Hz rotational line of water, allowing measurements of the integrated water vapor overburden in flight. In order to be useful in correcting the astronomical signals, the required measured precipitable water vapor accuracy must be 2 microns or better, 3 sigma, and measured at least once a minute. The Water Vapor Monitor has flown 22 times during the SOFIA Early Science shared-risk period. The instrument water vapor overburden data obtained were then compared with concurrent data from GOES-V satellites to perform a preliminary calibration of the measurements. This presentation will cover the.results of these flights. The final flight calibration necessary to reach the required accuracy will await subsequent flights following the SOFIA observatory upgrade that is taking place during the spring and summer of 2012.

  20. Development of the hard x-ray monitor onboard WF-MAXI

    Science.gov (United States)

    Arimoto, Makoto; Yatsu, Yoichi; Kawai, Nobuyuki; Ikeda, Hirokazu; Harayama, Atsushi; Takeda, Shin'ichiro; Takahashi, Tadayuki; Tomida, Hiroshi; Ueno, Shiro; Kimura, Masashi; Mihara, Tatehiro; Serino, Motoko; Tsunemi, Hiroshi; Yoshida, Atsumasa; Sakamoto, Takanori; Kohmura, Tadayoshi; Negoro, Hitoshi; Ueda, Yoshihiro

    2014-07-01

    WF-MAXI is a mission to detect and localize X-ray transients with short-term variability as gravitational-wave (GW) candidates including gamma-ray bursts, supernovae etc. We are planning on starting observations by WF-MAXI to be ready for the initial operation of the next generation GW telescopes (e.g., KAGRA, Advanced LIGO etc.). WF-MAXI consists of two main instruments, Soft X-ray Large Solid Angle Camera (SLC) and Hard X-ray Monitor (HXM) which totally cover 0.7 keV to 1 MeV band. HXM is a multi-channel array of crystal scintillators coupled with APDs observing photons in the hard X-ray band with an effective area of above 100 cm2. We have developed an analog application specific integrated circuit (ASIC) dedicated for the readout of 32-channel APDs' signals using 0.35 μm CMOS technology based on Open IP project and an analog amplifier was designed to achieve a low-noise readout. The developed ASIC showed a low-noise performance of 2080 e- + 2.3 e-/pF at root mean square and with a reverse-type APD coupled to a Ce:GAGG crystal a good FWHM energy resolution of 6.9% for 662 keV -rays.

  1. DOSIS & DOSIS 3D: long-term dose monitoring onboard the Columbus Laboratory of the International Space Station (ISS

    Directory of Open Access Journals (Sweden)

    Berger Thomas

    2016-01-01

    Full Text Available The radiation environment encountered in space differs in nature from that on Earth, consisting mostly of highly energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones present on Earth for occupational radiation workers. Since the beginning of the space era, the radiation exposure during space missions has been monitored with various active and passive radiation instruments. Also onboard the International Space Station (ISS, a number of area monitoring devices provide data related to the spatial and temporal variation of the radiation field in and outside the ISS. The aim of the DOSIS (2009–2011 and the DOSIS 3D (2012–ongoing experiments was and is to measure the radiation environment within the European Columbus Laboratory of the ISS. These measurements are, on the one hand, performed with passive radiation detectors mounted at 11 locations within Columbus for the determination of the spatial distribution of the radiation field parameters and, on the other, with two active radiation detectors mounted at a fixed position inside Columbus for the determination of the temporal variation of the radiation field parameters. Data measured with passive radiation detectors showed that the absorbed dose values inside the Columbus Laboratory follow a pattern, based on the local shielding configuration of the radiation detectors, with minimum dose values observed in the year 2010 of 195–270 μGy/day and maximum values observed in the year 2012 with values ranging from 260 to 360 μGy/day. The absorbed dose is modulated by (a the variation in solar activity and (b the changes in ISS altitude.

  2. DOSIS & DOSIS 3D: long-term dose monitoring onboard the Columbus Laboratory of the International Space Station (ISS)

    Science.gov (United States)

    Berger, Thomas; Przybyla, Bartos; Matthiä, Daniel; Reitz, Günther; Burmeister, Sönke; Labrenz, Johannes; Bilski, Pawel; Horwacik, Tomasz; Twardak, Anna; Hajek, Michael; Fugger, Manfred; Hofstätter, Christina; Sihver, Lembit; Palfalvi, Jozsef K.; Szabo, Julianna; Stradi, Andrea; Ambrozova, Iva; Kubancak, Jan; Brabcova, Katerina Pachnerova; Vanhavere, Filip; Cauwels, Vanessa; Van Hoey, Olivier; Schoonjans, Werner; Parisi, Alessio; Gaza, Ramona; Semones, Edward; Yukihara, Eduardo G.; Benton, Eric R.; Doull, Brandon A.; Uchihori, Yukio; Kodaira, Satoshi; Kitamura, Hisashi; Boehme, Matthias

    2016-11-01

    The radiation environment encountered in space differs in nature from that on Earth, consisting mostly of highly energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones present on Earth for occupational radiation workers. Since the beginning of the space era, the radiation exposure during space missions has been monitored with various active and passive radiation instruments. Also onboard the International Space Station (ISS), a number of area monitoring devices provide data related to the spatial and temporal variation of the radiation field in and outside the ISS. The aim of the DOSIS (2009-2011) and the DOSIS 3D (2012-ongoing) experiments was and is to measure the radiation environment within the European Columbus Laboratory of the ISS. These measurements are, on the one hand, performed with passive radiation detectors mounted at 11 locations within Columbus for the determination of the spatial distribution of the radiation field parameters and, on the other, with two active radiation detectors mounted at a fixed position inside Columbus for the determination of the temporal variation of the radiation field parameters. Data measured with passive radiation detectors showed that the absorbed dose values inside the Columbus Laboratory follow a pattern, based on the local shielding configuration of the radiation detectors, with minimum dose values observed in the year 2010 of 195-270 μGy/day and maximum values observed in the year 2012 with values ranging from 260 to 360 μGy/day. The absorbed dose is modulated by (a) the variation in solar activity and (b) the changes in ISS altitude.

  3. Monitoring Comet 67P/C-G Micrometer Dust Flux: GIADA onboard Rosetta.

    Science.gov (United States)

    Della Corte, Vincenzo; Rotundi, Alessandra; Ivanovski, Stavro; Accolla, Mario; Ferrari, Marco; Sordini, Roberto; Lucarelli, Francesca; Zakharov, Vladimir; Fulle, Marco; Mazzotta Epifani, Elena; López-Moreno, José J.; Rodríguez, Julio; Colangeli, Luigi; Palumbo, Pasquale; Bussoletti, Ezio; Crifo, Jean-Francois; Esposito, Francesca; Green, Simon F.; Grün, Eberhard; Lamy, Philippe L.

    2015-04-01

    (21)ESA-ESAC, Camino Bajo del Castillo, s/n., Urb. Villafranca del Castillo, 28692 Villanueva de la Cañada, Madrid, Spagna The MicroBalance System (MBS) is one of the three measurement subsystems of GIADA, the Grain Impact Analyzer and Dust Accumulator on board the Rosetta/ESA spacecraft (S/C). It consists of five Quartz Crystal Microbalances (QCMs) in roughly orthogonal directions providing the cumulative dust flux of grains smaller than 10 microns. The MBS is continuously monitoring comet 67P/CG since the beginning of May 2014. During the first 4 months of measurements, before the insertion of the S/C in the bound orbit phase, there were no evidences of dust accumulation on the QCMs. Starting from the beginning of October, three out of five QCMs measured an increase of the deposited dust. The measured fluxes show, as expected, a strong anisotropy. In particular, the dust flux appears to be much higher from the Sun direction with respect to the comet direction. Acknowledgment: GIADA was built by a consortum led by the Univ. Napoli "Parthenope" & INAF- Oss. Astr. Capodimonte, in collaboration with the Inst. de Astrofisica de Andalucia, Selex-ES, FI and SENER. GIADA is presently managed & operated by Ist. di Astrofisica e Planetologia Spaziali-INAF, IT. GIADA was funded and managed by the Agenzia Spaziale Italiana, IT, with the support of the Spanish Ministry of Education and Science MEC, ES. GIADA was developed from a PI proposal from the University of Kent; sci. & tech. contribution were provided by CISAS, IT, Lab. d'Astr. Spat., FR, and Institutions from UK, IT, FR, DE and USA. We thank the RSGS/ESAC, RMOC/ESOC & Rosetta Project/ESTEC for their out-standing work. Science support provided was by NASA through the US Rosetta Project managed by the Jet Propulsion Laboratory/ California Institute of Technology. GIADA calibrated data will be available through ESA's PSA web site (www.rssd.esa.int/index.php? project=PSA&page=in dex). We would like to thank Angioletta

  4. Operational Use of the Air Quality Monitor on ISS and Potential for Air Quality Monitoring Onboard Submarines

    Science.gov (United States)

    Limero, Thomas; Jones, Jared; Wallace, William; Mudgett, Paul

    2015-01-01

    The air quality monitor (AQM) began operations on the International Space Station (ISS) in March 2013 and was validated for operational use in January 2014. The AQM is a gas chromatograph-differential mobility spectrometer that currently monitors 22 target compounds in the ISS atmosphere. Data are collected twice per week, although data collection can be more frequent in contingency situations. In its second year, the AQM has provided data to decision-makers on several ISS contaminant related issues in both air and water. AQM has been used in strictly air incidents, such as a potential ammonia leak, and to investigate air contaminants affecting the water processing (excess ethanol). In the latter case data from water monitors and AQM were compared to understand the issue with the water processor. Additionally, the AQM has been moved to different ISS modules to determine whether air is sufficiently mixed between modules so that a central LAB module location is representative of the entire ISS atmosphere. Historic data on the ISS atmosphere in different modules from archival samples (ground lab analysis) suggest that the atmosphere is usually homogenous. This presentation will briefly describe the technical aspects of the AQM operations and summarize the validation results. The main focus of the presentation will be to discuss the results from the AQM survey of the ISS modules and to show how the AQM data has contributed to an understanding of environmental issues that have arisen on ISS. Presentation of a potential ammonia leak (indicated by an alarm) in 2015 will illustrate the use and value of the AQM in such situations.

  5. Measurement result of the neutron monitor onboard Space Environment Data Acquisition Equipment - Attached Payload (SEDA-AP)

    Science.gov (United States)

    Koga, K.; Matsumoto, H.; Okudaira, O.; Obara, T.; Yamamoto, T.; Muraki, Y.

    2011-12-01

    To support future space activities, it is very important to acquire the space environmental data which causes the degradation of space parts and spacecraft anomalies. Such data are useful for spacecraft design and manned space activity. Space Environment Data Acquisition - Attached Payload (SEDA-AP) measures the space environment around the International Space Station (ISS) by being attached to the Exposed Facility(EF) of the Japanese Experimental Module ("Kibo"). The Neutron Monitor (NEM) is one of the detectors in SEDA-AP. This instrument was developed to measure the solar neutrons which are produced by solar flare event. The solar neutron is a good indicator to clarify the acceleration mechanism of charged particles at the solar flare. Because of the energy of solar neutron is not influenced by the interplanetary magnetic field, it has the information of the energy of the accelerated charged particle directly. We have been analyzing the neutron data at several M or X class solar flare from September 2009. The mission objectives, instrumentation and measurement status of the neutron monitor are reported.

  6. Measurement of Solar Neutrons on 05 March 2012, Using a Fiber-Type Neutron Monitor Onboard the Attached Payload to the ISS

    Science.gov (United States)

    Koga, K.; Muraki, Y.; Masuda, S.; Shibata, S.; Matsumoto, H.; Kawano, H.

    2017-08-01

    The solar neutron detector Space Environment Data Acquisition Equipment - Attached Payload (SEDA-FIB) onboard the International Space Station (ISS) detected several events from the solar direction associated with three large solar flares observed on 05 (X1.1), 07 (X5.4), and 09 (M6.3) March 2012. In this study, we focus on the interesting event of 05 March, present the temporal profiles of the neutrons, and discuss the physics that may be related to a possible acceleration scenario for ions above the solar surface. We compare our data with images of the flares obtained by the ultraviolet telescope Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO).

  7. Accelerated Aging Experiments for Capacitor Health Monitoring and Prognostics

    Science.gov (United States)

    Kulkarni, Chetan S.; Celaya, Jose Ramon; Biswas, Gautam; Goebel, Kai

    2012-01-01

    This paper discusses experimental setups for health monitoring and prognostics of electrolytic capacitors under nominal operation and accelerated aging conditions. Electrolytic capacitors have higher failure rates than other components in electronic systems like power drives, power converters etc. Our current work focuses on developing first-principles-based degradation models for electrolytic capacitors under varying electrical and thermal stress conditions. Prognostics and health management for electronic systems aims to predict the onset of faults, study causes for system degradation, and accurately compute remaining useful life. Accelerated life test methods are often used in prognostics research as a way to model multiple causes and assess the effects of the degradation process through time. It also allows for the identification and study of different failure mechanisms and their relationships under different operating conditions. Experiments are designed for aging of the capacitors such that the degradation pattern induced by the aging can be monitored and analyzed. Experimental setups and data collection methods are presented to demonstrate this approach.

  8. Flow-accelerated corrosion monitoring through advanced sensors

    Science.gov (United States)

    Kim, Jung T.; Seong, Seung H.; Lee, Cheol K.; Hur, Sub; Lee, Na Y.; Lee, Sang J.

    2005-02-01

    In order to successfully implement the extended-life operation plan of the nuclear power plant (NPP), predictive maintenance based on on-line monitoring of deteriorated components becomes highly important. Pipe wall-thinning is usually caused by Flow-Accelerated Corrosion (FAC) under the undesirable combination of water chemistry, flow velocity and material composition. In order to increase the confidence of understanding on underlying process, a multi-disciplinary approach has been adopted in this work. Here, we apply a combination of several advanced sensors, ranging from chemical electrodes to mechanical vibration sensors to monitor the thickness change of the elbow, which can be still economical option. Electrochemical Corrosion Potential (ECP) and pH are chosen as electrochemical parameters, the change of vibration mode, displacement, and etc. are chosen as mechanical parameters to monitor the wall thinning phenomena. Electrodes are developed for the on-line monitoring of pH and ECP. Vibration is considered as a promising candidate as a mechanical parameter. Various sensors are surveyed and some are chosen based on FEM analysis result, which shows the approximate vibration range according to the thickness change. Mechanical sensors need to be sensitive enough to detect small thickness change with adequate safety margin to a pipe rupture. A few sensors are suggested to detect vibration or displacement quantitatively. Fiber optic sensors are chosen for their non-contacting property, which is appropriate for the high temperature application. Accelerometer and capacitance gage are suggested for their applicability fit to the test purpose.

  9. Results of a Measurement of Solar Neutrons Emitted on March 5, 2012 using a Fiber-type neutron monitor onboard the SEDA-AP attached to the ISS

    CERN Document Server

    Koga, K; Okudaira, O; Goka, T; Obara, T; Masuda, S; Muraki, Y; Shibata, S; Yamamoto, T

    2015-01-01

    The solar neutron detector SEDA-FIB onboard the International Space Station (ISS) has detected several events from the solar direction associated with three large solar flares observed on March 5th (X1.1), 7th (X5.4), and 9th (M6.3) of 2012. In this study, we present the time profiles of those neutrons and discuss the physics that may be related to a possible acceleration scenario for ions over the solar surface. We compare our data with the dynamical pictures of the flares obtained by the ultra-violet telescope of the space-based Solar Dynamics Observatory.

  10. Oil condition monitoring of gears onboard ships using a regression approach for multivariate T2 control charts

    DEFF Research Database (Denmark)

    Henneberg, Morten; Jørgensen, Bent; Eriksen, René Lynge

    2016-01-01

    only quasi-stationary data are included in phase I of the T2 statistics. Data from two thruster gears onboard two different ships are presented and analyzed, and the selection of the phase I data size is discussed. A graphic overview for quick localization of T2 signaling is also demonstrated using...

  11. An end-to-end examination of geometric accuracy of IGRT using a new digital accelerator equipped with onboard imaging system.

    Science.gov (United States)

    Wang, Lei; Kielar, Kayla N; Mok, Ed; Hsu, Annie; Dieterich, Sonja; Xing, Lei

    2012-02-01

    The Varian's new digital linear accelerator (LINAC), TrueBeam STx, is equipped with a high dose rate flattening filter free (FFF) mode (6 MV and 10 MV), a high definition multileaf collimator (2.5 mm leaf width), as well as onboard imaging capabilities. A series of end-to-end phantom tests were performed, TrueBeam-based image guided radiation therapy (IGRT), to determine the geometric accuracy of the image-guided setup and dose delivery process for all beam modalities delivered using intensity modulated radiation therapy (IMRT) and RapidArc. In these tests, an anthropomorphic phantom with a Ball Cube II insert and the analysis software (FilmQA (3cognition)) were used to evaluate the accuracy of TrueBeam image-guided setup and dose delivery. Laser cut EBT2 films with 0.15 mm accuracy were embedded into the phantom. The phantom with the film inserted was first scanned with a GE Discovery-ST CT scanner, and the images were then imported to the planning system. Plans with steep dose fall off surrounding hypothetical targets of different sizes were created using RapidArc and IMRT with FFF and WFF (with flattening filter) beams. Four RapidArc plans (6 MV and 10 MV FFF) and five IMRT plans (6 MV and 10 MV FFF; 6 MV, 10 MV and 15 MV WFF) were studied. The RapidArc plans with 6 MV FFF were planned with target diameters of 1 cm (0.52 cc), 2 cm (4.2 cc) and 3 cm (14.1 cc), and all other plans with a target diameter of 3 cm. Both onboard planar and volumetric imaging procedures were used for phantom setup and target localization. The IMRT and RapidArc plans were then delivered, and the film measurements were compared with the original treatment plans using a gamma criteria of 3%/1 mm and 3%/2 mm. The shifts required in order to align the film measured dose with the calculated dose distributions was attributed to be the targeting error. Targeting accuracy of image-guided treatment using TrueBeam was found to be within 1 mm. For irradiation of the 3 cm target, the gammas (3%, 1

  12. Monitoring of multiphase flows for superconducting accelerators and others applications

    Science.gov (United States)

    Filippov, Yu. P.; Kakorin, I. D.; Kovrizhnykh, A. M.; Miklayev, V. M.

    2017-07-01

    This paper is a review on implementation of measuring systems for two-phase helium, hydrogen, liquefied natural gas (LNG), and oil-formation/salty water flows. Two types of such systems are presented. The first type is based on two-phase flow-meters combining void fraction radio-frequency (RF) sensors and narrowing devices. They can be applied for superconducting accelerators cooled with two-phase helium, refueling hydrogen system for space ships and some applications in oil production industry. The second one is based on combination of a gamma-densitometer and a narrowing device. These systems can be used to monitor large two-phase LNG and oil-formation water flows. An electronics system based on a modular industrial computer is described as well. The metrological characteristics for different flow-meters are presented and the obtained results are discussed. It is also shown that the experience gained allows separationless flow-meter for three-phase oil-gas-formation water flows to be produced.

  13. JMS-based SOA monitors CERN particle accelerators

    CERN Multimedia

    Seeley, Rich

    2007-01-01

    "Service-oriented architecture (SOA) may not exactly be nuclear physics, but at the CERN (European Organization for Nuclear Research) physics laboratory on the border of France and Switzerland, an SOA system is watching over giant particle accelerators." (1,5 page)

  14. A system for monitoring the radiation effects of a proton linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Skorkin, V. M., E-mail: skorkin@inr.ru; Belyanski, K. L.; Skorkin, A. V. [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation)

    2016-12-15

    The system for real-time monitoring of radioactivity of a high-current proton linear accelerator detects secondary neutron emission from proton beam losses in transport channels and measures the activity of radionuclides in gas and aerosol emissions and the radiation background in the environment affected by a linear accelerator. The data provided by gamma, beta, and neutron detectors are transferred over a computer network to the central server. The system allows one to monitor proton beam losses, the activity of gas and aerosol emissions, and the radiation emission level of a linear accelerator in operation.

  15. Design and validation of wireless acceleration sensor network for structural health monitoring

    Institute of Scientific and Technical Information of China (English)

    Yu Yan; Ou Jinping

    2006-01-01

    A wireless sensor network is proposed to monitor the acceleration of structures for the purpose of structural health monitoring of civil engineering structures. Using commercially available parts, several modules are constructed and integrated into complete wireless sensors and base stations. The communication protocol is designed and the fusion arithmetic of the temperature and acceleration is embedded in the wireless sensor node so that the measured acceleration values are more accurate. Measures are adopted to finish energy optimization, which is an important issue for a wireless sensor network. The test is performed on an offshore platform model, and the experimental results are given to show the feasibility of the designed wireless sensor network.

  16. Wireless acceleration sensor of moving elements for condition monitoring of mechanisms

    Science.gov (United States)

    Sinitsin, Vladimir V.; Shestakov, Aleksandr L.

    2017-09-01

    Comprehensive analysis of the angular and linear accelerations of moving elements (shafts, gears) allows an increase in the quality of the condition monitoring of mechanisms. However, existing tools and methods measure either linear or angular acceleration with postprocessing. This paper suggests a new construction design of an angular acceleration sensor for moving elements. The sensor is mounted on a moving element and, among other things, the data transfer and electric power supply are carried out wirelessly. In addition, the authors introduce a method for processing the received information which makes it possible to divide the measured acceleration into the angular and linear components. The design has been validated by the results of laboratory tests of an experimental model of the sensor. The study has shown that this method provides a definite separation of the measured acceleration into linear and angular components, even in noise. This research contributes an advance in the range of methods and tools for condition monitoring of mechanisms.

  17. Set of instruments for solar EUV and soft X-ray monitoring onboard satellite Coronas-Photon

    Science.gov (United States)

    Kotov, Yury; Kochemasov, Alexey; Kuzin, Sergey; Kuznetsov, Vladimir; Sylwester, Janusz; Yurov, Vitaly

    Coronas-Photon mission is the third satellite of the Russian Coronas program on solar activity observation. The main goal of the "Coronas-Photon" is the study of solar hard electromagnetic radiation in the wide energy range from UV up to high energy gamma-radiation (2000MeV). Scientific payload for solar radiation observation consists of three types of instruments: Monitors (Natalya-2M, Konus-RF, RT-2, Penguin-M, BRM, PHOKA, Sphin-X, SOKOL spectral and timing measurements of full solar disk radiation have timing in flare/burst mode up to one msec. Instruments Natalya-2M, Konus-RF, RT-2 will cover the wide energy range of hard X-rays and soft gamma-rays (15keV to 2000MeV) and will together constitute the largest area detectors ever used for solar observations. Detectors of gamma-ray monitors are based on structured inorganic scintillators. For X-ray and EUV monitors the scintillation phoswich detectors, gas proportional counter, CdZnTe assembly and filter-covered Si-diodes are used. Telescope-spectrometer TESIS for imaging solar spectroscopy in X-rays has angular resolution up to 1arcsec in three spectral lines. Satellite platform and scientific payload is under construction to be launched in autumn 2008. Satellite orbit is circular with initial height 550km and inclination 82.5degrees. Accuracy of the spacecraft orientation to the Sun is better 3arcmin. In the report the capability of PHOKA, SphinX, SOKOL and TESIS as well as the observation program are described and discussed.

  18. Use of a digital camera onboard an unmanned aerial vehicle to monitor spring phenology at individual tree level

    Science.gov (United States)

    Berra, Elias; Gaulton, Rachel; Barr, Stuart

    2016-04-01

    The monitoring of forest phenology, in a cost-effective manner, at a fine spatial scale and over relatively large areas remains a significant challenge. To address this issue, unmanned aerial vehicles (UAVs) appear as a potential new option for forest phenology monitoring. The aim of this study is to assess the potential of imagery acquired from a UAV to track seasonal changes in leaf canopy at individual tree level. UAV flights, deploying consumer-grade standard and near-infrared modified cameras, were carried out over a deciduous woodland during the spring season of 2015, from which a temporal series of calibrated and georeferenced 5 cm spatial resolution orthophotos was generated. Initial results from a subset of trees are presented in this paper. Four trees with different observed Start of Season (SOS) dates were selected to monitor UAV-derived Green Chromatic Coordinate (GCC), as a measure of canopy greenness. Mean GCC values were extracted from within the four individual tree crowns and were plotted against the day of year (DOY) when the data were acquired. The temporal GCC trajectory of each tree was associated with the visual observations of leaf canopy phenology (SOS) and also with the development of understory vegetation. The chronological order when sudden increases of GCC values occurred matched with the chronological order of observed SOS: the first sudden increase in GCC was detected in the tree which first reached SOS; 18.5 days later (on average) the last sudden increase of GCC was detected in the tree which last reached SOS (18 days later than the first one). Trees with later observed SOS presented GCC values increasing slowly over time, which were associated with development of understory vegetation. Ongoing work is dealing with: 1) testing different indices; 2) radiometric calibration (retrieving of spectral reflectance); 3) expanding the analysis to more tree individuals, more tree species and over larger forest areas, and; 4) deriving

  19. Beam Position Monitor and Energy Analysis at the Fermilab Accelerator Science and Technology Facility

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, David Juarez [Univ. of Guanajuato (Mexico)

    2015-08-01

    Fermilab Accelerator Science and Technology Facility has produced its first beam with an energy of 20 MeV. This energy is obtained by the acceleration at the Electron Gun and the Capture Cavity 2 (CC2). When fully completed, the accelerator will consist of a photoinjector, one International Liner Collider (ILC)-type cryomodule, multiple accelerator R&D beamlines, and a downstream beamline to inject 300 MeV electrons into the Integrable Optics Test Accelerator (IOTA). We calculated the total energy of the beam and the corresponding energy to the Electron Gun and CC2. Subsequently, a Beam Position Monitors (BPM) error analysis was done, to calculate the device actual resolution.

  20. Prototyping of beam position monitor for medium energy beam transport section of RAON heavy ion accelerator

    Science.gov (United States)

    Jang, Hyojae; Jin, Hyunchang; Jang, Ji-Ho; Hong, In-Seok

    2016-02-01

    A heavy ion accelerator, RAON is going to be built by Rare Isotope Science Project in Korea. Its target is to accelerate various stable ions such as uranium, proton, and xenon from electron cyclotron resonance ion source and some rare isotopes from isotope separation on-line. The beam shaping, charge selection, and modulation should be applied to the ions from these ion sources because RAON adopts a superconducting linear accelerator structure for beam acceleration. For such treatment, low energy beam transport, radio frequency quadrupole, and medium energy beam transport (MEBT) will be installed in injector part of RAON accelerator. Recently, development of a prototype of stripline beam position monitor (BPM) to measure the position of ion beams in MEBT section is under way. In this presentation, design of stripline, electromagnetic (EM) simulation results, and RF measurement test results obtained from the prototyped BPM will be described.

  1. Prototyping of beam position monitor for medium energy beam transport section of RAON heavy ion accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hyojae, E-mail: lkcom@ibs.re.kr; Jin, Hyunchang; Jang, Ji-Ho; Hong, In-Seok [Rare Isotope Science Project, Institute for Basic Science, Daejeon (Korea, Republic of)

    2016-02-15

    A heavy ion accelerator, RAON is going to be built by Rare Isotope Science Project in Korea. Its target is to accelerate various stable ions such as uranium, proton, and xenon from electron cyclotron resonance ion source and some rare isotopes from isotope separation on-line. The beam shaping, charge selection, and modulation should be applied to the ions from these ion sources because RAON adopts a superconducting linear accelerator structure for beam acceleration. For such treatment, low energy beam transport, radio frequency quadrupole, and medium energy beam transport (MEBT) will be installed in injector part of RAON accelerator. Recently, development of a prototype of stripline beam position monitor (BPM) to measure the position of ion beams in MEBT section is under way. In this presentation, design of stripline, electromagnetic (EM) simulation results, and RF measurement test results obtained from the prototyped BPM will be described.

  2. Measurement result of the neutron monitor onboard the Space Environment Data Acquisition Equipment - Attached Payload (SEDA-AP)

    Science.gov (United States)

    Koga, K.; Muraki, Y.; Shibata, S.; Yamamoto, T.; Matsumoto, H.; Okudaira, O.; Kawano, H.; Yumoto, K.

    2013-12-01

    To support future space activities, it is crucial to acquire space environmental data related to the space-radiation degradation of space parts and materials, and spacecraft anomalies. Such data are useful for spacecraft design and manned space activity. SEDA-AP was mounted on 'Kibo' of the ISS (International Space Station) to measure the space environment at a 400-kilometer altitude. Neutrons are very harmful radiation, with electrical neutrality that makes them strongly permeable. SEDA-AP measures the energy of neutrons from thermal to 100 MeV in real time using a Bonner Ball Detector (BBND) and a Scintillation Fiber Detector (FIB). BBND detects neutrons using He-3 counters, which have high sensitivity to thermal neutrons. Neutron energy is derived using the relative response function of polyethylene moderators of 6 different thicknesses. FIB measures the tracks of recoil protons caused by neutrons within a cubic arrayed sensor of 512 scintillation fibers. The charged particles are excluded using an anti-scintillator which surrounds the cube sensor, and the neutron energy is obtained from the track length of a recoil proton. There are three sources of neutrons in space; 1. Albedo Neutrons Produced by reactions of galactic cosmic rays or radiation belt particles with the atmosphere 2. Local Neutrons Produced by the reactions of galactic cosmic rays or radiation belt particles with spacecraft 3. Solar Neutrons Produced by accelerated particles in solar flares An accurate energy spectrum of the solar neutrons includes important information on high-energy particle generation mechanism in a solar flare, because neutrons are unaffected by interplanetary magnetic fields. These data will become useful to forecast solar energetic particles in future. Some candidate events involving solar neutrons were found as a result of analyzing data of the solar flare of M>2 since September 2009. Moreover, it is important to measure albedo neutrons, since protons generated by neutron

  3. Dust Impact Monitor (DIM) onboard Rosetta/Philae: Comparison of experimental results and the theory behind the experiment

    Science.gov (United States)

    Flandes, Alberto; Krüger, Harald; Loose, Alexander; Sperl, Matthias; Jürgen Seidensticker, Klaus; Fischer, Hans-Herbert; Arnold, Walter

    2013-08-01

    The Dust Impact Monitor (DIM) experiment on board the Rosetta spacecraft's lander, Philae, is a cube with three sides covered with piezo-electric (PZT) sensors (total sensitive area: ≈70cm2), aimed at measuring the physical properties of millimetric and sub-millimetric dust particles that move near the surface of comet 67P/Churyumov - Gerasimenko. In this work we study the performance of the DIM Flight Spare (FS) unit based on impact experiments and compare the measurements with the sensor's expected theoretical behavior as derived from Hertz' theory of elastic impact. We present the results of impact experiments performed with spherical particles of different densities and elastic properties. We performed two types of experiments: (a) we analyze the performance of the different sensor sides under identical impacts, and (b) we investigate the performance of DIM under impacts of different materials and different impact speeds. We discuss the possible influence of the microstructure of the PZT sensor on the signal strength and its variation with position of the impacting particles. Our results show that the signal strength and the contact times measured with the DIM PZT sensors can be well approximated by Hertz' contact mechanics.

  4. Evaluation of energy response of neutron rem monitor applied to high-energy accelerator facilities

    Energy Technology Data Exchange (ETDEWEB)

    Nakane, Yoshihiro; Harada, Yasunori; Sakamoto, Yukio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

    2003-03-01

    A neutron rem monitor was newly developed for applying to the high-intensity proton accelerator facility (J-PARC) that is under construction as a joint project between the Japan Atomic Energy Research Institute and the High Energy Accelerator Research Organization. To measure the dose rate accurately for wide energy range of neutrons from thermal to high-energy region, the neutron rem monitor was fabricated by adding a lead breeder layer to a conventional neutron rem monitor. The energy response of the monitor was evaluated by using neutron transport calculations for the energy range from thermal to 150 MeV. For verifying the results, the response was measured at neutron fields for the energy range from thermal to 65 MeV. The comparisons between the energy response and dose conversion coefficients show that the newly developed neutron rem monitor has a good performance in energy response up to 150 MeV, suggesting that the present study offered prospects of a practical fabrication of the rem monitor applicable to the high intensity proton accelerator facility. (author)

  5. Real time monitoring of accelerated chemical reactions by ultrasonication-assisted spray ionization mass spectrometry.

    Science.gov (United States)

    Lin, Shu-Hsuan; Lo, Ta-Ju; Kuo, Fang-Yin; Chen, Yu-Chie

    2014-01-01

    Ultrasonication has been used to accelerate chemical reactions. It would be ideal if ultrasonication-assisted chemical reactions could be monitored by suitable detection tools such as mass spectrometry in real time. It would be helpful to clarify reaction intermediates/products and to have a better understanding of reaction mechanism. In this work, we developed a system for ultrasonication-assisted spray ionization mass spectrometry (UASI-MS) with an ~1.7 MHz ultrasonic transducer to monitor chemical reactions in real time. We demonstrated that simply depositing a sample solution on the MHz-based ultrasonic transducer, which was placed in front of the orifice of a mass spectrometer, the analyte signals can be readily detected by the mass spectrometer. Singly and multiply charged ions from small and large molecules, respectively, can be observed in the UASI mass spectra. Furthermore, the ultrasonic transducer used in the UASI setup accelerates the chemical reactions while being monitored via UASI-MS. The feasibility of using this approach for real-time acceleration/monitoring of chemical reactions was demonstrated. The reactions of Girard T reagent and hydroxylamine with steroids were used as the model reactions. Upon the deposition of reactant solutions on the ultrasonic transducer, the intermediate/product ions are readily generated and instantaneously monitored using MS within 1 s. Additionally, we also showed the possibility of using this reactive UASI-MS approach to assist the confirmation of trace steroids from complex urine samples by monitoring the generation of the product ions.

  6. The Development and Optimization of Techniques for Monitoring Water Quality on-Board Spacecraft Using Colorimetric Solid-Phase Extraction (C-SPE)

    Energy Technology Data Exchange (ETDEWEB)

    Hill, April Ann [Iowa State Univ., Ames, IA (United States)

    2007-12-01

    The main focus of this dissertation is the design, development, and ground and microgravity validation of methods for monitoring drinking water quality on-board NASA spacecraft using clorimetric-solid phase extraction (C-SPE). The Introduction will overview the need for in-flight water quality analysis and will detail some of the challenges associated with operations in the absence of gravity. The ability of C-SPE methods to meet these challenges will then be discussed, followed by a literature review on existing applications of C-SPE and similar techniques. Finally, a brief discussion of diffuse reflectance spectroscopy theory, which provides a means for analyte identification and quantification in C-SPE analyses, is presented. Following the Introduction, four research chapters are presented as separate manuscripts. Chapter 1 reports the results from microgravity testing of existing C-SPE methods and procedures aboard NASA's C-9 microgravity simulator. Chapter 2 discusses the development of a C-SPE method for determining the total concentration of biocidal silver (i.e., in both dissolved and colloidal forms) in water samples. Chapter 3 presents the first application of the C-SPE technique to the determination of an organic analyte (i.e., formaldehyde). Chapter 4, which is a departure from the main focus of the thesis, details the results of an investigation into the effect of substrate rotation on the kinetics involved in the antigen and labeling steps in sandwich immunoassays. These research chapters are followed by general conclusions and a prospectus section.

  7. Long-term monitoring of air crew exposure onboard of Czech Airlines aircraft; Monitorage a long terme de l'exposition du personnel navigant a bord d'un avion de la compagnie aerienne Czech Airlines

    Energy Technology Data Exchange (ETDEWEB)

    Ploc, O.; Spurny, F. [Nuclear Physics Institute AS CR, Dept. of Radiation Dosimetry, Prague (Czech Republic); Ploc, O. [Czech Technical Univ., Dept. of Dosimetry and Application of Ionizing Radiation, Prague (Czech Republic)

    2007-01-15

    This contribution presents new results related to the aircraft crew exposure onboard aircraft of Czech air companies. First, the results of long term monitoring onboard of an aircraft of Czech Airlines are presented. In the period May-December 2005, 494 individual flights have been followed using MDU-Liulin Si-diode based spectrometer, together with thermoluminescent and track detectors. The results of measurements are analyzed and compared with those of calculation performed with CARI6 and EPCARD3.2 codes. Monitoring period represented about 4.6 times more than usual annual engagement of an aircrew (600 hours). Total effective dose during these 2 755 hours was between Il and 12 mSv, following the considered method of evaluation. Both the measuring and calculation methods correlate well. This fact leads to confirmation of the routine method evaluating the level of aircraft crew exposure using CARI6 code as correct for this purpose. Second, the results of individual monitoring of aircrew members obtained during few last years by this routine method are presented; general tendencies of aircraft crew onboard exposure of Czech air companies are outlined. The contribution of aircrew exposure to total occupational exposure in the Czech Republic represents about 20%. (authors)

  8. Diamon2- Improved Monitoring of CERN’s Accelerator Controls Infrastructure

    CERN Document Server

    Buczak, W; Ehm, F; Jurcso, P; Mitev, M

    2014-01-01

    Monitoring of heterogeneous systems in large organizations like CERN is always challenging. CERN's accelerators infrastructure includes large number of equipment (servers, consoles, FECs, PLCs), some still running legacy software like LynxOS 4 or Red Hat Enterprise Linux 4 on older hardware with very limited resources. DIAMON2 is based on CERN Common Monitoring platform. Using Java industry standards, notably Spring, Ehcache and the Java Message Service, together with a small footprint C++ -based monitoring agent for real time systems and wide variety of additional data acquisition components (SNMP, JMS, JMX etc.), DIAMON2 targets CERN’s environment, providing easily extensible, dynamically reconfigurable, reliable and scalable monitoring solution. This article explains the evolution of the CERN diagnostics and monitoring environment until DIAMON2, describes the overall system’s architecture, main components and their functionality as well as the first operational experiences with the new system, observed...

  9. Self-Powered Acceleration Sensor Based on Liquid Metal Triboelectric Nanogenerator for Vibration Monitoring.

    Science.gov (United States)

    Zhang, Binbin; Zhang, Lei; Deng, Weili; Jin, Long; Chun, Fengjun; Pan, Hong; Gu, Bingni; Zhang, Haitao; Lv, Zekai; Yang, Weiqing; Wang, Zhong Lin

    2017-07-25

    An acceleration sensor is an essential component of the vibration measurement, while the passivity and sensitivity are the pivotal features for its application. Here, we report a self-powered and highly sensitive acceleration sensor based on a triboelectric nanogenerator composed of a liquid metal mercury droplet (LMMD) and nanofiber-networked polyvinylidene fluoride (nn-PVDF) film. Due to the ultrahigh surface-to-volume ratio of nn-PVDF film and high surface tension, high mass density, high elastic as well as mechanical robustness of LMMD, the open-circuit voltage and short-circuit current reach up to 15.5 V and 300 nA at the acceleration of 60 m/s(2), respectively. The acceleration sensor has a wide detection range from 0 to 60 m/s(2) with a high sensitivity of 0.26 V·s/m(2). Also, the output voltage and current show a negligible decrease over 200,000 cycles, evidently presenting excellent stability. Moreover, a high-speed camera was employed to dynamically capture the motion state of the acceleration sensor for insight into the corresponding work mechanism. Finally, the acceleration sensor was demonstrated to measure the vibration of mechanical equipment and human motion in real time, which has potential applications in equipment vibration monitoring and troubleshooting.

  10. Profile grid monitor and first measurement results at the MedAustron accelerator

    CERN Document Server

    Repovz, M; Kerschbaum, A; Osmic, F; Schwarz, S; Burtin, G

    2013-01-01

    MedAustron is a synchrotron based ion beam therapy center located in Wiener Neustadt/Austria. The MedAustron accelerator design is based on CERN’s Proton-Ion Medical Machine Study (PIMMS) [1] and is currently in the accelerator installation and beam commissioning phase. One of the basic measurements for commissioning of an accelerator is also beam profile measurement. The beam at the end of the Low Energy Beam Transport (LEBT) line and in the Medium Energy Beam Transport (MEBT) line (after the fast deflector) is pulsed. Due to pulsed beam the Wire Scanner Monitor (WSX) cannot be used. To measure a beam profile at these locations a new monitor has been developed – Profile Grid Monitor (PGX). The PGX is also known as harp grid monitor and it contains 64 wires positioned vertically and 64 wires horizontally for measuring the beam profile in both transverse planes. The PGX acquires the current of all 128 wires simultaneously, converts it to voltage, digitizes the values and processes the co...

  11. Gamma-ray and neutron area monitoring system of linear IFMIF prototype accelerator building

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hiroki, E-mail: takahashi.hiroki@jaea.go.jp [Japan Atomic Energy Agency (JAEA), Rokkasho, Aomori (Japan); Kojima, Toshiyuki; Narita, Takahiro; Tsutsumi, Kazuyoshi; Maebara, Sunao [Japan Atomic Energy Agency (JAEA), Rokkasho, Aomori (Japan); Sakaki, Hironao [JAEA, Kizugawa, Kyoto (Japan); Nishiyama, Koichi [IFMIF/EVEDA Project Team, Rokkasho, Aomori (Japan)

    2013-10-15

    Highlights: • Area monitoring system and control system are needed for LIPAc radiation management. • To secure the radiation safety, these systems are linked with two kinds of data path. • Hardwired data paths are adopted to realize the fast transfer of interlock signals. • Dual LAN and shared memory are adopted to the reliable transfer of monitoring data. • Data transfers without unnecessary load are designed and configured for these systems. -- Abstract: The linear IFMIF prototype accelerator (LIPAc) produces deuteron beam with 1 MW power. Since huge number of neutrons occur from such a high power beam, therefore, it is important for the radiation management to design a high reliability area monitoring system for gamma-rays and neutrons. To obtain the valuable operation data of the high-power deuteron beam at LIPAc, it is important to link and record the beam operation data and the area monitoring data. We realize the reliable data transfer to provide the area monitoring data to the accelerator control system which needs a high reliability using the shared-memory data link method. This paper describes the area monitoring system in the LIPAc building and the data-link between this system and the LIPAc control system.

  12. Complex Event Processing Approach To Automated Monitoring Of Particle Accelerator And Its Control System

    Directory of Open Access Journals (Sweden)

    Karol Grzegorczyk

    2014-01-01

    Full Text Available This article presents the design and implementation of a software component for automated monitoring and diagnostic information analysis of a particle accelerator and its control system. The information that is analyzed can be seen as streams of events. A Complex Event Processing (CEP approach to event processing was selected. The main advantage of this approach is the ability to continuously query data coming from several streams. The presented software component is based on Esper, the most popular open-source implementation of CEP. As a test bed, the control system of the accelerator complex located at CERN, the European Organization for Nuclear Research, was chosen. The complex includes the Large Hadron Collider, the world’s most powerful accelerator. The main contribution to knowledge is by showing that the CEP approach can successfully address many of the challenges associated with automated monitoring of the accelerator and its control system that were previously unsolved. Test results, performance analysis, and a proposal for further works are also presented.

  13. Monitoring oil displacement processes with k-t accelerated spin echo SPI.

    Science.gov (United States)

    Li, Ming; Xiao, Dan; Romero-Zerón, Laura; Balcom, Bruce J

    2016-03-01

    Magnetic resonance imaging (MRI) is a robust tool to monitor oil displacement processes in porous media. Conventional MRI measurement times can be lengthy, which hinders monitoring time-dependent displacements. Knowledge of the oil and water microscopic distribution is important because their pore scale behavior reflects the oil trapping mechanisms. The oil and water pore scale distribution is reflected in the magnetic resonance T2 signal lifetime distribution. In this work, a pure phase-encoding MRI technique, spin echo SPI (SE-SPI), was employed to monitor oil displacement during water flooding and polymer flooding. A k-t acceleration method, with low-rank matrix completion, was employed to improve the temporal resolution of the SE-SPI MRI measurements. Comparison to conventional SE-SPI T2 mapping measurements revealed that the k-t accelerated measurement was more sensitive and provided higher-quality results. It was demonstrated that the k-t acceleration decreased the average measurement time from 66.7 to 20.3 min in this work. A perfluorinated oil, containing no (1) H, and H2 O brine were employed to distinguish oil and water phases in model flooding experiments. High-quality 1D water saturation profiles were acquired from the k-t accelerated SE-SPI measurements. Spatially and temporally resolved T2 distributions were extracted from the profile data. The shift in the (1) H T2 distribution of water in the pore space to longer lifetimes during water flooding and polymer flooding is consistent with increased water content in the pore space. Copyright © 2015 John Wiley & Sons, Ltd.

  14. Flexusi Interface Builder For Computer Based Accelerator Monitoring And Control System

    CERN Document Server

    Kurakin, V G; Kurakin, P V

    2004-01-01

    We have developed computer code for any desired graphics user interface designing for monitoring and control system at the executable level. This means that operator can build up measurement console consisting of virtual devices before or even during real experiment without recompiling source file. Such functionality results in number of advantages comparing with traditional programming. First of all any risk disappears to introduce bug into source code. Another important thing is the fact the both program developers and operator staff do not interface in developing ultimate product (measurement console). Thus, small team without detailed project can design even very complicated monitoring and control system. For the reason mentioned below, approach suggested is especially helpful for large complexes to be monitored and control, accelerator being among them. The program code consists of several modules, responsible for data acquisition, control and representation. Borland C++ Builder technologies based on VCL...

  15. Comparison of Raw Acceleration from the GENEA and ActiGraph™ GT3X+ Activity Monitors

    OpenAIRE

    Dinesh John; Jeffer Sasaki; John Staudenmayer; Marianna Mavilia; Freedson, Patty S

    2013-01-01

    Purpose: To compare raw acceleration output of the ActiGraph™ GT3X+ and GENEA activity monitors. Methods: A GT3X+ and GENEA were oscillated in an orbital shaker at frequencies ranging from 0.7 to 4.0 Hz (ten 2-min trials/frequency) on a fixed radius of 5.08 cm. Additionally, 10 participants (age = 23.8 ± 5.4 years) wore the GT3X+ and GENEA on the dominant wrist and performed treadmill walking (2.0 and 3.5 mph) and running (5.5 and 7.5 mph) and simulated free-living activities (computer work, ...

  16. Development of a synchrotron radiation beam monitor for the Integrable Optics Test Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Scarpelli, Andrea [Univ. of Ferrara (Italy)

    2016-01-01

    Nonlinear integrable optics applied to beam dynamics may mitigate multi-particle instabilities, but proof of principle experiments have never been carried out. The Integrable Optics Test Accelerator (IOTA) is an electron and proton storage ring currently being built at Fermilab, which addresses tests of nonlinear lattice elements in a real machine in addition to experiments on optical stochastic cooling and on the single-electron wave function. These experiments require an outstanding control over the lattice parameters, achievable with fast and precise beam monitoring systems. This work describes the steps for designing and building a beam monitor for IOTA based on synchrotron radiation, able to measure intensity, position and transverse cross-section beam.

  17. Comparison of Raw Acceleration from the GENEA and ActiGraph™ GT3X+ Activity Monitors

    Directory of Open Access Journals (Sweden)

    Dinesh John

    2013-10-01

    Full Text Available Purpose: To compare raw acceleration output of the ActiGraph™ GT3X+ and GENEA activity monitors. Methods: A GT3X+ and GENEA were oscillated in an orbital shaker at frequencies ranging from 0.7 to 4.0 Hz (ten 2-min trials/frequency on a fixed radius of 5.08 cm. Additionally, 10 participants (age = 23.8 ± 5.4 years wore the GT3X+ and GENEA on the dominant wrist and performed treadmill walking (2.0 and 3.5 mph and running (5.5 and 7.5 mph and simulated free-living activities (computer work, cleaning a room, vacuuming and throwing a ball for 2-min each. A linear mixed model was used to compare the mean triaxial vector magnitude (VM from the GT3X+ and GENEA at each oscillation frequency. For the human testing protocol, random forest machine-learning technique was used to develop two models using frequency domain (FD and time domain (TD features for each monitor. We compared activity type recognition accuracy between the GT3X+ and GENEA when the prediction model was fit using one monitor and then applied to the other. Z-statistics were used to compare the proportion of accurate predictions from the GT3X+ and GENEA for each model. Results: GENEA produced significantly higher (p < 0.05, 3.5 to 6.2% mean VM than GT3X+ at all frequencies during shaker testing. Training the model using TD input features on the GENEA and applied to GT3X+ data yielded significantly lower (p < 0.05 prediction accuracy. Prediction accuracy was not compromised when interchangeably using FD models between monitors. Conclusions: It may be inappropriate to apply a model developed on the GENEA to predict activity type using GT3X+ data when input features are TD attributes of raw acceleration.

  18. Comparison of Raw Acceleration from the GENEA and ActiGraph™ GT3X+ Activity Monitors

    Science.gov (United States)

    John, Dinesh; Sasaki, Jeffer; Staudenmayer, John; Mavilia, Marianna; Freedson, Patty S.

    2013-01-01

    Purpose: To compare raw acceleration output of the ActiGraph™ GT3X+ and GENEA activity monitors. Methods: A GT3X+ and GENEA were oscillated in an orbital shaker at frequencies ranging from 0.7 to 4.0 Hz (ten 2-min trials/frequency) on a fixed radius of 5.08 cm. Additionally, 10 participants (age = 23.8 ± 5.4 years) wore the GT3X+ and GENEA on the dominant wrist and performed treadmill walking (2.0 and 3.5 mph) and running (5.5 and 7.5 mph) and simulated free-living activities (computer work, cleaning a room, vacuuming and throwing a ball) for 2-min each. A linear mixed model was used to compare the mean triaxial vector magnitude (VM) from the GT3X+ and GENEA at each oscillation frequency. For the human testing protocol, random forest machine-learning technique was used to develop two models using frequency domain (FD) and time domain (TD) features for each monitor. We compared activity type recognition accuracy between the GT3X+ and GENEA when the prediction model was fit using one monitor and then applied to the other. Z-statistics were used to compare the proportion of accurate predictions from the GT3X+ and GENEA for each model. Results: GENEA produced significantly higher (p < 0.05, 3.5 to 6.2%) mean VM than GT3X+ at all frequencies during shaker testing. Training the model using TD input features on the GENEA and applied to GT3X+ data yielded significantly lower (p < 0.05) prediction accuracy. Prediction accuracy was not compromised when interchangeably using FD models between monitors. Conclusions: It may be inappropriate to apply a model developed on the GENEA to predict activity type using GT3X+ data when input features are TD attributes of raw acceleration. PMID:24177727

  19. Physical Activities Monitoring Using Wearable Acceleration Sensors Attached to the Body.

    Science.gov (United States)

    Arif, Muhammad; Kattan, Ahmed

    2015-01-01

    Monitoring physical activities by using wireless sensors is helpful for identifying postural orientation and movements in the real-life environment. A simple and robust method based on time domain features to identify the physical activities is proposed in this paper; it uses sensors placed on the subjects' wrist, chest and ankle. A feature set based on time domain characteristics of the acceleration signal recorded by acceleration sensors is proposed for the classification of twelve physical activities. Nine subjects performed twelve different types of physical activities, including sitting, standing, walking, running, cycling, Nordic walking, ascending stairs, descending stairs, vacuum cleaning, ironing clothes and jumping rope, and lying down (resting state). Their ages were 27.2 ± 3.3 years and their body mass index (BMI) is 25.11 ± 2.6 Kg/m2. Classification results demonstrated a high validity showing precision (a positive predictive value) and recall (sensitivity) of more than 95% for all physical activities. The overall classification accuracy for a combined feature set of three sensors is 98%. The proposed framework can be used to monitor the physical activities of a subject that can be very useful for the health professional to assess the physical activity of healthy individuals as well as patients.

  20. Physical Activities Monitoring Using Wearable Acceleration Sensors Attached to the Body.

    Directory of Open Access Journals (Sweden)

    Muhammad Arif

    Full Text Available Monitoring physical activities by using wireless sensors is helpful for identifying postural orientation and movements in the real-life environment. A simple and robust method based on time domain features to identify the physical activities is proposed in this paper; it uses sensors placed on the subjects' wrist, chest and ankle. A feature set based on time domain characteristics of the acceleration signal recorded by acceleration sensors is proposed for the classification of twelve physical activities. Nine subjects performed twelve different types of physical activities, including sitting, standing, walking, running, cycling, Nordic walking, ascending stairs, descending stairs, vacuum cleaning, ironing clothes and jumping rope, and lying down (resting state. Their ages were 27.2 ± 3.3 years and their body mass index (BMI is 25.11 ± 2.6 Kg/m2. Classification results demonstrated a high validity showing precision (a positive predictive value and recall (sensitivity of more than 95% for all physical activities. The overall classification accuracy for a combined feature set of three sensors is 98%. The proposed framework can be used to monitor the physical activities of a subject that can be very useful for the health professional to assess the physical activity of healthy individuals as well as patients.

  1. Physical Activities Monitoring Using Wearable Acceleration Sensors Attached to the Body

    Science.gov (United States)

    2015-01-01

    Monitoring physical activities by using wireless sensors is helpful for identifying postural orientation and movements in the real-life environment. A simple and robust method based on time domain features to identify the physical activities is proposed in this paper; it uses sensors placed on the subjects’ wrist, chest and ankle. A feature set based on time domain characteristics of the acceleration signal recorded by acceleration sensors is proposed for the classification of twelve physical activities. Nine subjects performed twelve different types of physical activities, including sitting, standing, walking, running, cycling, Nordic walking, ascending stairs, descending stairs, vacuum cleaning, ironing clothes and jumping rope, and lying down (resting state). Their ages were 27.2 ± 3.3 years and their body mass index (BMI) is 25.11 ± 2.6 Kg/m2. Classification results demonstrated a high validity showing precision (a positive predictive value) and recall (sensitivity) of more than 95% for all physical activities. The overall classification accuracy for a combined feature set of three sensors is 98%. The proposed framework can be used to monitor the physical activities of a subject that can be very useful for the health professional to assess the physical activity of healthy individuals as well as patients. PMID:26203909

  2. SDO Onboard Ephemeris Generation

    Science.gov (United States)

    Berry, Kevin E.; Liu, Kuo-Chia

    2008-01-01

    The Solar Dynamics Observatory (SDO) spacecraft is a sun-pointing, semi-autonomous satellite that will allow nearly continuous observations of the Sun with a continuous science data downlink. The science requirements for this mission necessitate very strict sun-pointing requirements, as well as continuous ground station connectivity through high gain antennas (HGAs). For SDO s onboard attitude control system to successfully point the satellite at the Sun and the HGAs at the ground stations with the desired accuracy, in addition to the need for accurate sensors it must have good onboard knowledge of the ephemerides of the Sun, the spacecraft, and the ground station. This paper describes the minimum force models necessary for onboard ephemeris generation in support of an attitude control system. The forces that were considered include the Sun s point mass, Moon s point mass, solar radiation pressure (SRP), and the Earth s gravity with varying degree and order of terms of the geopotential.

  3. Oil condition monitoring of gears onboard ships using a regression approach for multivariate T2 control charts

    DEFF Research Database (Denmark)

    Henneberg, Morten; Jørgensen, Bent; Eriksen, René Lynge

    2016-01-01

    In this paper, we present an oil condition and wear debris evaluation method for ship thruster gears using T2 statistics to form control charts from a multi-sensor platform. The proposed method takes into account the different ambient conditions by multiple linear regression on the mean value...... as substitution from the normal empirical mean value. This regression approach accounts for the bias imposed on the empirical mean value due to different geographical and seasonal differences on the multi-sensor inputs. Data from a gearbox are used to evaluate the length of the run-in period in order to ensure...... only quasi-stationary data are included in phase I of the T2 statistics. Data from two thruster gears onboard two different ships are presented and analyzed, and the selection of the phase I data size is discussed. A graphic overview for quick localization of T2 signaling is also demonstrated using...

  4. Fiber Bragg Grating Sensors Based Monitoring System for Superconducting Accelerator Magnets

    CERN Document Server

    Chiuchiolo, A; Perez, J C; Bajas, H; Consales, M; Giordano, M; Breglio, G; Cusano, A

    2014-01-01

    New generation of accelerator magnets for high energy applications currently designed, manufactured and tested at the European Organization for Nuclear Research (CERN) require the implementation of precise cryogenic sensors with long-term robustness and reliability able to withstand cryogenic temperature and to monitor the mechanical stresses affecting the winding during all the stages of his service life, assembly, cool down and powering. Monitoring the mechanical behavior of the magnet from assembly to operation is a critical task which aims to assure the integrity of the magnet and to safely handle the coils made of new brittle material. This contribution deals with the first successful embedding of Fiber Bragg Grating sensors in a subscale Nb3Sn dipole magnet in order to monitor the strain developed in the coil during the cool down to 1.9 K, the powering up to 15.8 kA and the warm up, offering new perspectives for the development of a complementary sensing technology based on fiber optic sensors.

  5. Cavity beam position monitor system for the Accelerator Test Facility 2

    Directory of Open Access Journals (Sweden)

    Y. I. Kim

    2012-04-01

    Full Text Available The Accelerator Test Facility 2 (ATF2 is a scaled demonstrator system for final focus beam lines of linear high energy colliders. This paper describes the high resolution cavity beam position monitor (BPM system, which is a part of the ATF2 diagnostics. Two types of cavity BPMs are used, C-band operating at 6.423 GHz, and S-band at 2.888 GHz with an increased beam aperture. The cavities, electronics, and digital processing are described. The resolution of the C-band system with attenuators was determined to be approximately 250 nm and 1  μm for the S-band system. Without attenuation the best recorded C-band cavity resolution was 27 nm.

  6. High throughput phenotyping to accelerate crop breeding and monitoring of diseases in the field.

    Science.gov (United States)

    Shakoor, Nadia; Lee, Scott; Mockler, Todd C

    2017-08-01

    Effective implementation of technology that facilitates accurate and high-throughput screening of thousands of field-grown lines is critical for accelerating crop improvement and breeding strategies for higher yield and disease tolerance. Progress in the development of field-based high throughput phenotyping methods has advanced considerably in the last 10 years through technological progress in sensor development and high-performance computing. Here, we review recent advances in high throughput field phenotyping technologies designed to inform the genetics of quantitative traits, including crop yield and disease tolerance. Successful application of phenotyping platforms to advance crop breeding and identify and monitor disease requires: (1) high resolution of imaging and environmental sensors; (2) quality data products that facilitate computer vision, machine learning and GIS; (3) capacity infrastructure for data management and analysis; and (4) automated environmental data collection. Accelerated breeding for agriculturally relevant crop traits is key to the development of improved varieties and is critically dependent on high-resolution, high-throughput field-scale phenotyping technologies that can efficiently discriminate better performing lines within a larger population and across multiple environments. Copyright © 2017. Published by Elsevier Ltd.

  7. Accuracy evaluation of the optical surface monitoring system on EDGE linear accelerator in a phantom study.

    Science.gov (United States)

    Mancosu, Pietro; Fogliata, Antonella; Stravato, Antonella; Tomatis, Stefano; Cozzi, Luca; Scorsetti, Marta

    2016-01-01

    Frameless stereotactic radiosurgery (SRS) requires dedicated systems to monitor the patient position during the treatment to avoid target underdosage due to involuntary shift. The optical surface monitoring system (OSMS) is here evaluated in a phantom-based study. The new EDGE linear accelerator from Varian (Varian, Palo Alto, CA) integrates, for cranial lesions, the common cone beam computed tomography (CBCT) and kV-MV portal images to the optical surface monitoring system (OSMS), a device able to detect real-time patient׳s face movements in all 6 couch axes (vertical, longitudinal, lateral, rotation along the vertical axis, pitch, and roll). We have evaluated the OSMS imaging capability in checking the phantoms׳ position and monitoring its motion. With this aim, a home-made cranial phantom was developed to evaluate the OSMS accuracy in 4 different experiments: (1) comparison with CBCT in isocenter location, (2) capability to recognize predefined shifts up to 2° or 3cm, (3) evaluation at different couch angles, (4) ability to properly reconstruct the surface when the linac gantry visually block one of the cameras. The OSMS system showed, with a phantom, to be accurate for positioning in respect to the CBCT imaging system with differences of 0.6 ± 0.3mm for linear vector displacement, with a maximum rotational inaccuracy of 0.3°. OSMS presented an accuracy of 0.3mm for displacement up to 1cm and 1°, and 0.5mm for larger displacements. Different couch angles (45° and 90°) induced a mean vector uncertainty < 0.4mm. Coverage of 1 camera produced an uncertainty < 0.5mm. Translations and rotations of a phantom can be accurately detect with the optical surface detector system.

  8. Accuracy evaluation of the optical surface monitoring system on EDGE linear accelerator in a phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Mancosu, Pietro; Fogliata, Antonella, E-mail: Antonella.Fogliata@humanitas.it; Stravato, Antonella; Tomatis, Stefano; Cozzi, Luca; Scorsetti, Marta

    2016-07-01

    Frameless stereotactic radiosurgery (SRS) requires dedicated systems to monitor the patient position during the treatment to avoid target underdosage due to involuntary shift. The optical surface monitoring system (OSMS) is here evaluated in a phantom-based study. The new EDGE linear accelerator from Varian (Varian, Palo Alto, CA) integrates, for cranial lesions, the common cone beam computed tomography (CBCT) and kV-MV portal images to the optical surface monitoring system (OSMS), a device able to detect real-time patient's face movements in all 6 couch axes (vertical, longitudinal, lateral, rotation along the vertical axis, pitch, and roll). We have evaluated the OSMS imaging capability in checking the phantoms' position and monitoring its motion. With this aim, a home-made cranial phantom was developed to evaluate the OSMS accuracy in 4 different experiments: (1) comparison with CBCT in isocenter location, (2) capability to recognize predefined shifts up to 2° or 3 cm, (3) evaluation at different couch angles, (4) ability to properly reconstruct the surface when the linac gantry visually block one of the cameras. The OSMS system showed, with a phantom, to be accurate for positioning in respect to the CBCT imaging system with differences of 0.6 ± 0.3 mm for linear vector displacement, with a maximum rotational inaccuracy of 0.3°. OSMS presented an accuracy of 0.3 mm for displacement up to 1 cm and 1°, and 0.5 mm for larger displacements. Different couch angles (45° and 90°) induced a mean vector uncertainty < 0.4 mm. Coverage of 1 camera produced an uncertainty < 0.5 mm. Translations and rotations of a phantom can be accurately detect with the optical surface detector system.

  9. Development of the Vehicle Real-Time Running Status Monitoring and On-Board Diagnostic System%汽车实时运行状态监控及在线故障诊断系统的研制

    Institute of Scientific and Technical Information of China (English)

    潘可贤; 陈晓冰

    2009-01-01

    The vehicle real-time running status monitoring and on-board diagnostic system is designed to meet the need of diagnosing vehicle for private cars owners. The functions, such as the real-time data flow reading and recording, on-board diagnostic, voice reminding, displaying error code and corresponding content with liq-uid crystal displayer, data transferring via universal serial bus, are provided by this system. Furthermore, owner-drivers are able to know the running status of the vehicles, monitor whether their cars are in good condition, and then to locate malfunctioning parts via KWP1281/ISO9141/ISO14230(KWP20OO)/SAE J1850 VPW/SAE J1850 PWM/ISO15765 protocols to ensure safe driving and reduce the cost of maintenance.%针对当前私家车车主对汽车故障诊断的实际需求,提出汽车实时运行状态监控及在线故障诊断系统.该系统集成了汽车实时数据流读取和记录、故障诊断、语音提醒、故障码和故障内容LCD显示、USB数据传输等功能,完成了KWP1281/ISO9141/ISO14230(KWP2000)/SAE J1850 VPW/SAE J1850PWM/ISO15765协议的通信,使车主能够及时了解车辆的行驶状态,及时完成车辆运行监控、故障定位,以保证行车安全,并降低维修保养费用.

  10. Monitoring accelerated carbonation on standard Portland cement mortar by nonlinear resonance acoustic test

    Science.gov (United States)

    Eiras, J. N.; Kundu, T.; Popovics, J. S.; Monzó, J.; Borrachero, M. V.; Payá, J.

    2015-03-01

    Carbonation is an important deleterious process for concrete structures. Carbonation begins when carbon dioxide (CO2) present in the atmosphere reacts with portlandite producing calcium carbonate (CaCO3). In severe carbonation conditions, C-S-H gel is decomposed into silica gel (SiO2.nH2O) and CaCO3. As a result, concrete pore water pH decreases (usually below 10) and eventually steel reinforcing bars become unprotected from corrosion agents. Usually, the carbonation of the cementing matrix reduces the porosity, because CaCO3 crystals (calcite and vaterite) occupy more volume than portlandite. In this study, an accelerated carbonation-ageing process is conducted on Portland cement mortar samples with water to cement ratio of 0.5. The evolution of the carbonation process on mortar is monitored at different levels of ageing until the mortar is almost fully carbonated. A nondestructive technique based on nonlinear acoustic resonance is used to monitor the variation of the constitutive properties upon carbonation. At selected levels of ageing, the compressive strength is obtained. From fractured surfaces the depth of carbonation is determined with phenolphthalein solution. An image analysis of the fractured surfaces is used to quantify the depth of carbonation. The results from resonant acoustic tests revealed a progressive increase of stiffness and a decrease of material nonlinearity.

  11. Coupling MCNP-DSP and LAHET Monte Carlo codes for designing subcriticality monitors for accelerator-driven systems

    Energy Technology Data Exchange (ETDEWEB)

    Valentine, T.; Perez, R. [Oak Ridge National Lab., TN (United States); Rugama, Y.; Munoz-Cobo, J.L. [Poly. Tech. Univ. of Valencia (Spain). Chemical and Nuclear Engineering Dept.

    2001-07-01

    The design of reactivity monitoring systems for accelerator-driven systems must be investigated to ensure that such systems remain subcritical during operation. The Monte Carlo codes LAHET and MCNP-DSP were combined together to facilitate the design of reactivity monitoring systems. The coupling of LAHET and MCNP-DSP provides a tool that can be used to simulate a variety of subcritical measurements such as the pulsed neutron, Rossi-{alpha}, or noise analysis measurements. (orig.)

  12. Coupling MCNP-DSP and LAHET Monte Carlo Codes for Designing Subcriticality Monitors for Accelerator-Driven Systems

    Energy Technology Data Exchange (ETDEWEB)

    Valentine, T.E.; Rugama, Y. Munoz-Cobos, J.; Perez, R.

    2000-10-23

    The design of reactivity monitoring systems for accelerator-driven systems must be investigated to ensure that such systems remain subcritical during operation. The Monte Carlo codes LAHET and MCNP-DSP were combined together to facilitate the design of reactivity monitoring systems. The coupling of LAHET and MCNP-DSP provides a tool that can be used to simulate a variety of subcritical measurements such as the pulsed neutron, Rossi-{alpha}, or noise analysis measurements.

  13. Calibration of area monitors for neutrons used in clinical linear accelerators; Calibracao de monitores de area para neutrons usados em aceleradores lineares clinicos

    Energy Technology Data Exchange (ETDEWEB)

    Salgado, Ana Paula; Pereira, Walsan Wagner; Patrao, Karla C. de Souza; Fonseca, Evaldo S. da, E-mail: asalgado@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Batista, Delano V.S. [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil)

    2009-07-01

    This work demonstrates the complexity and the necessary cares for the realization of measurements of neutron fields in rooms for radiotherapy treatment containing clinical accelerators. The acquaintance of the technical characteristics of the monitors and the periodic calibration are actions and fundamental procedures to guarantee traceability and the reliability of measurements

  14. Cardiac Acceleration at the Onset of Exercise : A Potential Parameter for Monitoring Progress During Physical Training in Sports and Rehabilitation

    NARCIS (Netherlands)

    Hettinga, Florentina J.; Monden, Paul G.; van Meeteren, Nico L. U.; Daanen, Hein A. M.

    There is a need for easy-to-use methods to assess training progress in sports and rehabilitation research. The present review investigated whether cardiac acceleration at the onset of physical exercise (HRonset) can be used as a monitoring variable. The digital databases of Scopus and PubMed were

  15. Cardiac acceleration at the onset of exercise: A potential parameter for monitoring progress during physical training in sports and rehabilitation

    NARCIS (Netherlands)

    Hettinga, F.J.; Monden, P.G.; Meeteren, N.L.U. van; Daanen, H.A.M.

    2014-01-01

    There is a need for easy-to-use methods to assess training progress in sports and rehabilitation research. The present review investigated whether cardiac acceleration at the onset of physical exercise (HRonset) can be used as a monitoring variable. The digital databases of Scopus and PubMed were

  16. Cardiac Acceleration at the Onset of Exercise : A Potential Parameter for Monitoring Progress During Physical Training in Sports and Rehabilitation

    NARCIS (Netherlands)

    Hettinga, Florentina J.; Monden, Paul G.; van Meeteren, Nico L. U.; Daanen, Hein A. M.

    2014-01-01

    There is a need for easy-to-use methods to assess training progress in sports and rehabilitation research. The present review investigated whether cardiac acceleration at the onset of physical exercise (HRonset) can be used as a monitoring variable. The digital databases of Scopus and PubMed were se

  17. A microprocessor-based system for continuous monitoring of radiation levels around the CERN PS and PSB accelerators

    Science.gov (United States)

    Agoritsas, V.; Beck, F.; Benincasa, G. P.; Bovigny, J. P.

    1986-06-01

    This paper describes a new beam loss monitor system which has been installed in the PS and PSB machines, replacing an earlier system. The new system is controlled by a microprocessor which can operate independently of the accelerator control system, though setting up and central display are usually done remotely, using the standard control system facilities.

  18. Microprocessor-based system for continuous monitoring of radiation levels around the CERN PS and PSB accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Agoritsas, V.; Beck, F.; Benincasa, G.P.; Bovigny, J.P.

    1986-06-01

    This paper describes a new beam loss monitor system which has been installed in the PS and PSB machines, replacing an earlier system. The new system is controlled by a microprocessor which can operate independently of the accelerator control system, though setting up and central display are usually done remotely, using the standard control system facilities.

  19. About the Big Graphs Arising when Forming the Diagnostic Models in a Reconfigurable Computing Field of Functional Monitoring and Diagnostics System of the Spacecraft Onboard Control Complex

    Directory of Open Access Journals (Sweden)

    L. V. Savkin

    2015-01-01

    Full Text Available One of the problems in implementation of the multipurpose complete systems based on the reconfigurable computing fields (RCF is the problem of optimum redistribution of logicalarithmetic resources in growing scope of functional tasks. Irrespective of complexity, all of them are transformed into an orgraph, which functional and topological structure is appropriately imposed on the RCF based, as a rule, on the field programmable gate array (FPGA.Due to limitation of the hardware configurations and functions realized by means of the switched logical blocks (SLB, the abovementioned problem becomes even more critical when there is a need, within the strictly allocated RCF fragment, to realize even more complex challenge in comparison with the problem which was solved during the previous computing step. In such cases it is possible to speak about graphs of big dimensions with respect to allocated RCF fragment.The article considers this problem through development of diagnostic algorithms to implement diagnostics and control of an onboard control complex of the spacecraft using RCF. It gives examples of big graphs arising with respect to allocated RCF fragment when forming the hardware levels of a diagnostic model, which, in this case, is any hardware-based algorithm of diagnostics in RCF.The article reviews examples of arising big graphs when forming the complicated diagnostic models due to drastic difference in formation of hardware levels on closely located RCF fragments. It also pays attention to big graphs emerging when the multichannel diagnostic models are formed.Three main ways to solve the problem of big graphs with respect to allocated RCF fragment are given. These are: splitting the graph into fragments, use of pop-up windows with relocating and memorizing intermediate values of functions of high hardware levels of diagnostic models, and deep adaptive update of diagnostic model.It is shown that the last of three ways is the most efficient

  20. Monitoring of Rotor-Stator Interaction in Pump-Turbine Using Vibrations Measured with On-Board Sensors Rotating with Shaft

    OpenAIRE

    Cristian G. Rodriguez; Borja Mateos-Prieto; Eduard Egusquiza

    2014-01-01

    Current trends in design of pump-turbines have led into higher rotor-stator interaction (RSI) loads over impeller-runner. These dynamic loads are of special interest having produced catastrophic failures in pump-turbines. Determining RSI characteristics facilitates the proposal of actions that will prevent these failures. Pressure measurements all around the perimeter of the impeller-runner are appropriate to monitor and detect RSI characteristics. Unfortunately most installed pump-turbines a...

  1. Reconstruction of lattice parameters and beam momentum distribution from turn-by-turn beam position monitor readings in circular accelerators

    Directory of Open Access Journals (Sweden)

    C. S. Edmonds

    2014-05-01

    Full Text Available In high chromaticity circular accelerators, rapid decoherence of the betatron motion of a particle beam can make the measurement of lattice and bunch values, such as Courant-Snyder parameters and betatron amplitude, difficult. A method for reconstructing the momentum distribution of a beam from beam position measurements is presented. Further analysis of the same beam position monitor data allows estimates to be made of the Courant-Snyder parameters and the amplitude of coherent betatron oscillation of the beam. The methods are tested through application to data taken on the linear nonscaling fixed field alternating gradient accelerator, EMMA.

  2. The Cognitive Onboard Operator Assistant Architecture Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a cognitively inspired architecture for deploying an automated intelligent onboard operator assistant. This assistant facilitates the onboard control...

  3. Onboard hierarchical network

    Science.gov (United States)

    Tunesi, Luca; Armbruster, Philippe

    2004-02-01

    The objective of this paper is to demonstrate a suitable hierarchical networking solution to improve capabilities and performances of space systems, with significant recurrent costs saving and more efficient design & manufacturing flows. Classically, a satellite can be split in two functional sub-systems: the platform and the payload complement. The platform is in charge of providing power, attitude & orbit control and up/down-link services, whereas the payload represents the scientific and/or operational instruments/transponders and embodies the objectives of the mission. One major possibility to improve the performance of payloads, by limiting the data return to pertinent information, is to process data on board thanks to a proper implementation of the payload data system. In this way, it is possible to share non-recurring development costs by exploiting a system that can be adopted by the majority of space missions. It is believed that the Modular and Scalable Payload Data System, under development by ESA, provides a suitable solution to fulfil a large range of future mission requirements. The backbone of the system is the standardised high data rate SpaceWire network http://www.ecss.nl/. As complement, a lower speed command and control bus connecting peripherals is required. For instance, at instrument level, there is a need for a "local" low complexity bus, which gives the possibility to command and control sensors and actuators. Moreover, most of the connections at sub-system level are related to discrete signals management or simple telemetry acquisitions, which can easily and efficiently be handled by a local bus. An on-board hierarchical network can therefore be defined by interconnecting high-speed links and local buses. Additionally, it is worth stressing another important aspect of the design process: Agencies and ESA in particular are frequently confronted with a big consortium of geographically spread companies located in different countries, each one

  4. On-Board Monitoring of Engine Oil

    Science.gov (United States)

    2011-04-01

    REPORT NUMBER(S) 21542 12. DISTRIBUTION /AVAILABILITY STATEMENT Approved for public release, distribution unlimited 13. SUPPLEMENTARY NOTES A Thesis...concentration* *Using techniques such as FTIR and wear particle analysis ( WPA ) Table 4: Level of significance for lubricant properties. Adapted from... distribution around the engine oil, while using less engine oil. By comparing the set-ups, it was possible to determine if the accuracy and precision of the

  5. Monitoring extracted beams of the nuclotron accelerator complex for "energy + transmutation" experiments

    Science.gov (United States)

    Baldin, A. A.; Berlev, A. I.; Vasil'ev, S. E.; Vishnevskiy, A. V.; Vladimirova, N. M.; Kudashkin, I. V.; Makan'kin, A. M.; Paraipan, M.; Tyutyunnikov, S. I.

    2016-03-01

    A monitoring system for measuring absolute intensity and the space—time structure of extracted beams of Nuclotron based on ionization and activation methods has been created and tested. The monitoring system provides a measurement of the absolute intensity of extracted beams with a precision of 10% and beam position with a precision of 0.5 mm.

  6. Upgrading the Digital Electronics of the PEP-II Bunch Current Monitors at the Stanford Linear Accelerator Center

    Energy Technology Data Exchange (ETDEWEB)

    Kline, Josh; /SLAC

    2006-08-28

    The testing of the upgrade prototype for the bunch current monitors (BCMs) in the PEP-II storage rings at the Stanford Linear Accelerator Center (SLAC) is the topic of this paper. Bunch current monitors are used to measure the charge in the electron/positron bunches traveling in particle storage rings. The BCMs in the PEP-II storage rings need to be upgraded because components of the current system have failed and are known to be failure prone with age, and several of the integrated chips are no longer produced making repairs difficult if not impossible. The main upgrade is replacing twelve old (1995) field programmable gate arrays (FPGAs) with a single Virtex II FPGA. The prototype was tested using computer synthesis tools, a commercial signal generator, and a fast pulse generator.

  7. The monitoring of transient regimes on machine tools based on speed, acceleration and active electric power absorbed by motors

    Science.gov (United States)

    Horodinca, M.

    2016-08-01

    This paper intend to propose some new results related with computer aided monitoring of transient regimes on machine-tools based on the evolution of active electrical power absorbed by the electric motor used to drive the main kinematic chains and the evolution of rotational speed and acceleration of the main shaft. The active power is calculated in numerical format using the evolution of instantaneous voltage and current delivered by electrical power system to the electric motor. The rotational speed and acceleration of the main shaft are calculated based on the signal delivered by a sensor. Three real-time analogic signals are acquired with a very simple computer assisted setup which contains a voltage transformer, a current transformer, an AC generator as rotational speed sensor, a data acquisition system and a personal computer. The data processing and analysis was done using Matlab software. Some different transient regimes were investigated; several important conclusions related with the advantages of this monitoring technique were formulated. Many others features of the experimental setup are also available: to supervise the mechanical loading of machine-tools during cutting processes or for diagnosis of machine-tools condition by active electrical power signal analysis in frequency domain.

  8. Note: Real-time monitoring via second-harmonic interferometry of a flow gas cell for laser wakefield acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Brandi, F., E-mail: fernando.brandi@ino.it [Intense Laser Irradiation Laboratory (ILIL), Istituto Nazionale di Ottica (INO-CNR), Via Moruzzi 1, 56124 Pisa (Italy); Istituto Italiano di Tecnologia (IIT), Via Morego 30, 16163 Genova (Italy); Giammanco, F.; Conti, F. [Dipartimento di Fisica, Università degli Studi di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Plasma Diagnostics and Technologies Ltd., via Matteucci n.38/D, 56124 Pisa (Italy); Sylla, F. [SourceLAB SAS, 86 Rue de Paris, 91400 Orsay (France); Lambert, G. [LOA, ENSTA ParisTech, CNRS, Ecole Polytechnique, Université Paris-Saclay, 828 bd des Maréchaux, 91762 Palaiseau Cedex (France); Gizzi, L. A. [Intense Laser Irradiation Laboratory (ILIL), Istituto Nazionale di Ottica (INO-CNR), Via Moruzzi 1, 56124 Pisa (Italy)

    2016-08-15

    The use of a gas cell as a target for laser wakefield acceleration (LWFA) offers the possibility to obtain stable and manageable laser-plasma interaction process, a mandatory condition for practical applications of this emerging technique, especially in multi-stage accelerators. In order to obtain full control of the gas particle number density in the interaction region, thus allowing for a long term stable and manageable LWFA, real-time monitoring is necessary. In fact, the ideal gas law cannot be used to estimate the particle density inside the flow cell based on the preset backing pressure and the room temperature because the gas flow depends on several factors like tubing, regulators, and valves in the gas supply system, as well as vacuum chamber volume and vacuum pump speed/throughput. Here, second-harmonic interferometry is applied to measure the particle number density inside a flow gas cell designed for LWFA. The results demonstrate that real-time monitoring is achieved and that using low backing pressure gas (<1 bar) and different cell orifice diameters (<2 mm) it is possible to finely tune the number density up to the 10{sup 19} cm{sup −3} range well suited for LWFA.

  9. OpenGL hardware accelerated algorithms for autostereoscopic monitor pattern creation

    Science.gov (United States)

    Husak, Michal; Ward, Chris

    2005-03-01

    Autostereoscopic monitors generally require complicated image pattern creation based on reprocessing of multiple scene views. The computational power necessary for such reprocessing is very high when real-time output of images is required at refresh rates higher than 24 fps and at high output resolutions from 1600x1200, to as much as 3840 x 2400. The optimal method is to do such reprocessing by the help of graphic card HW and not by CPU. We solved output creation for 3 types of autostereosopic monitors: generic autostereoscopic monitors requiring column-interlaced pattern, the Sharp RD3D autostereoscopic notebook, and monitors based on StereoGraphics SynthaGram principles. OpenGL stencil buffer operations were used for implementation of the output for monitors requiring column-interlaced patterns as well as output for Sharp RD3D notebook. We have tested 3 different implementations of SynthaGram like pattern creation - pure fixed pipeline OpenGL 1.2 method, nVidia Cg based GPU programming method, and a method using a mixture of both approaches. Benchmarking of all methods on different nVidia graphic card models were made. We were primary focused on application for multi-view stereoscopic video processing in DepthQ Stereoscopic Media Server software during the development, but identical methods as used for video could be employed for real time CG scene reprocessing.

  10. Stability study of the higher order mode beam position monitors at the Accelerating cavities at FLASH

    CERN Document Server

    Shi, L; Jones., R M

    2014-01-01

    erating cavities at FLASH linac, DESY, are equipped with electronics for beam position monitoring, which are based on HOM signals from special couplers. These monitors provide the beam position without additional vacuum components and at low cost. Moreover, they can be used to align the beam in the cavities to reduce the HOM effects on the beam. However, the HOMBPM (Higher Order Mode based Beam Position Monitor) shows an instability problem over time. In this paper, we will present the status of studies on this issue. Several methods are utilized to calibrate the HOMBPMs. These methods include DLR (Direct Linear Regression), and SVD (Singular Value Decomposition). We found that SVD generally is more suitable for HOMBPM calibration. We focus on the HOMBPMs at 1.3 GHz cavities. Techniques developed here are applicable to 3.9 ...

  11. Inflight magnetic characterization of the test masses onboard LISA Pathfinder

    CERN Document Server

    Diaz-Aguiló, Marc; Lobo, Alberto

    2012-01-01

    LISA Pathfinder is a science and technology demonstrator of the European Space Agency within the framework of its LISA mission, the latter aiming to be the first space-borne gravitational wave observatory. The payload of LISA Pathfinder is the so-called LISA Technology Package, which is designed to measure relative accelerations between two test masses in nominal free fall. The diagnostics subsystem consists of several modules, one of which is the magnetic diagnostics unit. Its main function is the assessment of the differential acceleration noise between the test masses due to magnetic effects. This subsystem is composed of two onboard coils intended to produce controlled magnetic fields at the location of the test masses. These magnetic fields couple with the remanent magnetic moment and susceptibility and produce forces and torques on the test masses. These, in turn, produce kinematic excursions of the test masses which are sensed by the onboard interferometer. We prove that adequately processing these exc...

  12. Detection of weak frequency jumps for GNSS onboard clocks.

    Science.gov (United States)

    Huang, Xinming; Gong, Hang; Ou, Gang

    2014-05-01

    In this paper, a weak frequency jump detection method is developed for onboard clocks in global navigation satellite systems (GNSS). A Kalman filter is employed to facilitate the onboard real-time processing of atomic clock measurements, whose N-step prediction residuals are used to construct the weak frequency jump detector. Numerical simulations show that the method can successfully detect weak frequency jumps. The detection method proposed in this paper is helpful for autonomous integrity monitoring of GNSS satellite clocks, and can also be applied to other frequency anomalies with an appropriately modified detector.

  13. MEMS acceleration sensor with remote optical readout for continuous power generator monitoring

    Directory of Open Access Journals (Sweden)

    Tormen Maurizio

    2015-01-01

    Full Text Available Miniaturized accelerometers with remote optical readout are required devices for the continuous monitoring of vibrations inside power generators. In turbo and hydro generators, end-winding vibrations are present during operation causing in the long term undesirable out-of-service repairs. Continuous monitoring of these vibrations is therefore mandatory. The high electromagnetic fields in the generators impose the use of devices immune to electromagnetic interferences. In this paper a MEMS based accelerometer with remote optical readout is presented. Advantages of the proposed device are the use of a differential optical signal to reject the common mode signal and noise, the reduced number of steps for the MEMS chip fabrication and for the system assembly, and the reduced package volume.

  14. On-board measurements of exhaust (OBM); On-Board Messungen von Abgas (OBM)

    Energy Technology Data Exchange (ETDEWEB)

    Heinze, H.E.

    1997-06-18

    The European Union intends to introduce on-board diagnosis of car exhaust emissions (OBD) from 2000, i.e. emission control by monitoring the various exhaust-relevant components of a motor car by an on-board computer. OBD is already in use in the USA (OBD I) and will be replaced by OBD step by step from 1995. In the present project, two systems by Messrs. WWU GmbH, Hamburg, will be investigated for the components CO and HC. For this purpose, comparative measurements with a FTIR spectrometer (SESAM = System for Emission Sampling and Measurement) are made using an exhaust dynamometer. (orig.) [Deutsch] Zur weiteren Verminderung der Emissionen schaedlicher Abgase aus Kraftfahrzeugen ist es in der Europaeischen Union vorgesehen, ab dem Jahre 2000 die On-Board Diagnose (OBD) einzufuehren. Darunter versteht man ein System zur Emissionskontrolle durch die Ueberwachung der Funktionsfaehigkeit der einzelnen abgasrelevanten Bauteile eines Kraftfahrzeugs durch den Fahrzeugcomputer. In den USA gibt es schon laenger eine erste Form der OBD fuer Pkw (OBD I), die ab dem Modelljahr 1995 schrittweise durch die weitergehende OBD II abgeloest wird. In diesem Vorhaben sollen zwei NDIR-Geraete der Firma WWU GmbH, Hamburg, auf ihre Eignung fuer den OBM-Einsatz ueberprueft werden, zunaechst nur fuer die Komponenten CO und HC. Dazu werden Vergleichsmessungen mit einem FTIR-Spektrometer (SESAM=System for Emission Sampling and Measurement) an einem Pkw auf dem Abgasrollenpruefstand durchgefuehrt. (orig.)

  15. Development of a Compton Camera for Online Range Monitoring of Laser-Accelerated Proton Beams via Prompt-Gamma Detection

    Directory of Open Access Journals (Sweden)

    Thirolf P.G.

    2014-03-01

    Full Text Available Presently large efforts are conducted in Munich towards the development of proton beams for bio-medical applications, generated via the technique of particle acceleration from high-power, short-pulse lasers. While so far mostly offline diagnostics tools are used in this context, we aim at developing a reliable and accurate online range monitoring technique, based on the position-sensitive detection of prompt γ rays emitted from nuclear reactions between the proton beam and the biological sample. For this purpose, we develop a Compton camera, designed to be able to track not only the Compton scattering of the primary photon, but also to detect the secondary Compton electron, thus reducing the Compton cone to an arc segment and by this increasing the source reconstruction efficiency. Design specifications and the status of the protype system are discussed.

  16. Monitoring the FLASH Cryomodule Transportation from DESY Hamburg to CEA Saclay: Coupler Contact, Vacuum, Acceleration and Vibration Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Barbanotti, S.; Bosotti, A.; Fusetti, M.; Michelato, P.; /INFN, Milan /LASA, Segrate; Bertolini, A.; /Hannover, Max Planck Inst. Grav.; Berry, S.; Dorlot, M.; Madec, C.; Napoly, O.; /Saclay; Amirikas, R.; Boehnert, M.; /DESY /Fermilab

    2009-05-01

    With a view to the series production of one hundred, 12 m long XFEL 1.3 GHz cryomodules and their transportation from the assembly site at CEA Saclay (F) to the installation site at DESY Hamburg (D) a test transportation of a FLASH cryomodule has been performed, in the condition foreseen for the mass transportation. The present study examines the stresses induced on the module and verifies the damping capabilities of the transport frame in order to minimize risk of damage to the most critical components. During the transportation, acceleration and vibration have been monitored as well as coupler antenna contacts and vacuum performances. This paper describes the analysis performed and compares those results to the data of a similar transportation study at Fermilab for the CM1 cryomodule.

  17. Wall-Current-Monitor based Ghost and Satellite Bunch Detection in the CERN PS and the LHC Accelerators

    CERN Document Server

    Steinhagen, R J; Belleman, J; Bohl, T; Damerau, H

    2012-01-01

    While most LHC detectors and instrumentation systems are optimised for a nominal bunch spacing of 25 ns, the LHC RF cavities themselves operate at the 10th harmonic of the maximum bunch frequency. Due to the beam production scheme and transfers in the injector chain, part of the nominally ‘empty’ RF buckets may contain particles, referred to as ghost or satellite bunches. These populations must be accurately quantified for high-precision experiments, luminosity calibration and control of parasitic particle encounters at the four LHC interaction points. This contribution summarises the wall-current-monitor based ghost and satellite bunch measurements in CERN’s PS and LHC accelerators. Instrumentation set-up, post-processing and achieved performance are discussed.

  18. Study of the characteristics of neutron monitor area applied to the evaluation of dose rates in a 15 MeV radiotherapy accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Candido M. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Fisica]. E-mail: candido_1998@yahoo.com; Patrao, Karla C.S.; Pereira, Walsan W.; Fonseca, Evaldo S.; Giannoni, Ricardo A. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Neutrons]. E-mails: karla@ird.gov.br; walsan@ird.gov.br; Batista, Delano V.S. [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil). Setor de Fisica Medica]. E-mail: delano@inca.gov.br

    2007-07-01

    Currently, in Radiotherapy, the use of linear accelerators is becoming each time more common. From Radiation Protection point of view, these instruments represent an advance in relation to the cobalt and caesium irradiators, mainly due to absence of the radioactive material. On the other hand, accelerators with the energies superior to 10 MeV produce contamination of the therapeutic beam with the presence of neutrons generated in the interaction of high-energy photons with high atomic number materials from the own irradiator. The present work carries through measurements in a linear accelerator of 15 MeV using three neutron area monitors for a comparison of the response of these instruments, evaluating its adequacy to this measurement. Characteristics of use and operation associates to parameters such as: monitor dead time, monitor gamma rejection, and calibration results are also analyzed in this study. (author)

  19. Monitoring method of neutron flux for the spallation target used in an accelerator driven sub-critical systems

    CERN Document Server

    Zhao, Qiang; Yang, Lei; Zhang, Xueying; Cui, Wenjuan; Chen, Zhiqiang; Xu, Hushan

    2015-01-01

    In this paper, we study the monitoring method of neutron flux for the spallation target used in an accelerator driven sub-critical (ADS) system, where the spallation target located vertically at the centre of a sub-critical core is bombarded vertically by the high-energy protons from an accelerator. First, by considering the characteristics in the spatial variation of neutron flux from the spallation target, we propose the following multi-point measurement technique, i.e. the spallation neutron flux should be measured at multiple vertical locations. To explain why the flux should be measured at multiple locations, we have studied the neutron production from tungsten target bombarded by a 250 MeV-proton beam with the Geant4-based Monte Carlo simulations. The simulation results have indicated that the neutron flux at the central location is up to three orders of magnitude higher than the flux at the lower locations. Secondly, we have developed an effective technique in order to measure the spallation neutron fl...

  20. Development of a system for monitoring the shape, position, and intensity of the extracted relativistic ion beam at the Nuclotron-M accelerator complex at JINR

    Science.gov (United States)

    Vasilev, S. E.; Vishnevskiy, A. V.; Kadykov, M. G.; Makankin, A. M.; Tyutyunnikov, S. I.; Shurygin, A. A.

    2014-11-01

    Test samples of detectors and electronics for them constructed for the purpose of monitoring the "intense" relativistic ion beams extracted from the accelerator of the Nuclotron-M accelerator complex in real time are described. The system was tested in a series of acceleration runs with deuteron beams with an intensity of up to 1010 1/s and beams of carbon nuclei. The system allows one to perform multiple measurements of the two-dimensional distribution of the beam intensity in the plane perpendicular to it and the beam position in this plane during the beam dump and measure the two-dimensional distribution of the target irradiation dose after each beam dump.

  1. New On-board Microprocessors

    Science.gov (United States)

    Weigand, R.

    Two new processor devices have been developed for the use on board of spacecrafts. An 8-bit 8032-microcontroller targets typical controlling applications in instruments and sub-systems, or could be used as a main processor on small satellites, whereas the LEON 32-bit SPARC processor can be used for high performance controlling and data processing tasks. The ADV80S32 is fully compliant to the Intel 80x1 architecture and instruction set, extended by additional peripherals, 512 bytes on-chip RAM and a bootstrap PROM, which allows downloading the application software using the CCSDS PacketWire pro- tocol. The memory controller provides a de-multiplexed address/data bus, and allows to access up to 16 MB data and 8 MB program RAM. The peripherals have been de- signed for the specific needs of a spacecraft, such as serial interfaces compatible to RS232, PacketWire and TTC-B-01, counters/timers for extended duration and a CRC calculation unit accelerating the CCSDS TM/TC protocol. The 0.5 um Atmel manu- facturing technology (MG2RT) provides latch-up and total dose immunity; SEU fault immunity is implemented by using SEU hardened Flip-Flops and EDAC protection of internal and external memories. The maximum clock frequency of 20 MHz allows a processing power of 3 MIPS. Engineering samples are available. For SW develop- ment, various SW packages for the 8051 architecture are on the market. The LEON processor implements a 32-bit SPARC V8 architecture, including all the multiply and divide instructions, complemented by a floating-point unit (FPU). It includes several standard peripherals, such as timers/watchdog, interrupt controller, UARTs, parallel I/Os and a memory controller, allowing to use 8, 16 and 32 bit PROM, SRAM or memory mapped I/O. With on-chip separate instruction and data caches, almost one instruction per clock cycle can be reached in some applications. A 33-MHz 32-bit PCI master/target interface and a PCI arbiter allow operating the device in a plug-in card

  2. Measurements of the relative backscatter contribution to the monitor chamber for modern medical linear accelerators; A multi-center study

    DEFF Research Database (Denmark)

    Sibolt, Patrik; Cronholm, Rickard O.; Beierholm, Anders Ravnsborg

    2015-01-01

    Conversion to absolute dose in Monte Carlo (MC) simulations of MV radiotherapy beams needs correct modeling of backscatter (BS) to the linear accelerator (linac) monitor chamber. For some linacs the BS depends largely on jaw settings. The backscattered fraction (BSF) of radiation can be determine...... also indicates that the method used for target charge measurements is reproducible. The reproducibility lies mainly in the fact that the method basically has no set-up errors and therefore is user independent....... experimentally by measuring ratios of target charge for a given number of monitor units as a function of jaw settings. This was done using the in-house developed ME40 dosimetry system, which is able to determine the target charge for each radiation pulse from the linac. The BSF measurements were performed...... for different linac models at five Danish radiotherapy clinics. The investigated linacs were four Varian TrueBeams (TB), one Varian iX (iX) and one Elekta Synergy (ES). BSF measurements were performed for square field side lengths ranging from 1 to 40 cm, using the 10 × 10 cm2 field as reference. The impact...

  3. Differential B-dot and D-dot monitors for current and voltage measurements on a 20-MA 3-MV pulsed-power accelerator.

    Energy Technology Data Exchange (ETDEWEB)

    Shoup, Roy Willlam (ITT Industries, Albuquerque, NM); Gilliland, Terrance Leo (Ktech Corporation, Albuquerque, NM); Lee, James R.; Speas, Christopher Shane; Kim, Alexandre A. (High Current Electronic Institute, Russian Academy of Sciences, Tomsk, Russia); Struve, Kenneth William; York, Mathew William; Leifeste, Gordon T.; Rochau, Gregory Alan; Sharpe, Arthur William; Stygar, William A.; Porter, John Larry Jr.; Wagoner, Tim C. (Ktech Corporation, Albuquerque, NM); Reynolds, Paul Gerard (Team Specialty Products Corporation, Albuquerque, NM); Slopek, Jeffrey Scott (Ktech Corporation, Albuquerque, NM); Moore, William B. S.; Dinwoodie, Thomas Albert (Ktech Corporation, Albuquerque, NM); Woodring, R. M. (Ktech Corporation, Albuquerque, NM); Broyles, Robin Scott (Ktech Corporation, Albuquerque, NM); Mills, Jerry Alan; Melville, J. A. (Prodyn Technologies Incorporated, Albuquerque, NM); Dudley, M. E. (Ktech Corporation, Albuquerque, NM); Androlewicz, K. E. (Ktech Corporation, Albuquerque, NM); Mourning, R. W. (Ktech Corporation, Albuquerque, NM); Moore, J. K. (Ktech Corporation, Albuquerque, NM); Serrano, Jason Dimitri (Ktech Corporation, Albuquerque, NM); Ives, H. C. (EG& G, Albuquerque, NM); Johnson, M. F. (Team Specialty Products Corporation, Albuquerque, NM); Peyton, B. P. (Ktech Corporation, Albuquerque, NM); Leeper, Ramon Joe; Savage, Mark Edward; Donovan, Guy Louis; Spielman, R. B. (Ktech Corporation, Albuquerque, NM); Seamen, Johann F.

    2007-12-01

    We have developed a system of differential-output monitors that diagnose current and voltage in the vacuum section of a 20-MA 3-MV pulsed-power accelerator. The system includes 62 gauges: 3 current and 6 voltage monitors that are fielded on each of the accelerator's 4 vacuum-insulator stacks, 6 current monitors on each of the accelerator's 4 outer magnetically insulated transmission lines (MITLs), and 2 current monitors on the accelerator's inner MITL. The inner-MITL monitors are located 6 cm from the axis of the load. Each of the stack and outer-MITL current monitors comprises two separate B-dot sensors, each of which consists of four 3-mm-diameter wire loops wound in series. The two sensors are separately located within adjacent cavities machined out of a single piece of copper. The high electrical conductivity of copper minimizes penetration of magnetic flux into the cavity walls, which minimizes changes in the sensitivity of the sensors on the 100-ns time scale of the accelerator's power pulse. A model of flux penetration has been developed and is used to correct (to first order) the B-dot signals for the penetration that does occur. The two sensors are designed to produce signals with opposite polarities; hence, each current monitor may be regarded as a single detector with differential outputs. Common-mode-noise rejection is achieved by combining these signals in a 50-{Omega} balun. The signal cables that connect the B-dot monitors to the balun are chosen to provide reasonable bandwidth and acceptable levels of Compton drive in the bremsstrahlung field of the accelerator. A single 50-{omega} cable transmits the output signal of each balun to a double-wall screen room, where the signals are attenuated, digitized (0.5-ns/sample), numerically compensated for cable losses, and numerically integrated. By contrast, each inner-MITL current monitor contains only a single B-dot sensor. These monitors are fielded in opposite-polarity pairs. The two

  4. Measurement of back-scattered radiation from micro multileaf collimator into the beam monitor chamber from a dual energy linear accelerator

    Directory of Open Access Journals (Sweden)

    Muralidhar K

    2007-01-01

    Full Text Available Measurements designed to find the collimator backscatter into the beam monitor chamber from Micro Multileaf collimator of 6 MV photon beams of the Siemens Primus linear accelerator were made with the help of dose rate feedback control. The photons and electrons backscattered from the upper and lower secondary collimator jaws give rise to a significant increase in the ion charge measured by monitor chamber. This increase varies between the different accelerators. The output measurements were carried out in air at the isocenter. The effect of collimator backscatter was investigated by measuring the pulse width, number of beam pulses per monitor unit, monitor unit rate and dose for different mMLC openings. These measurements were made with and without dose rate feedback control, i.e., with constant electron beam current in the accelerator. Monitor unit rate (MU/min was almost constant for all field sizes. The maximum variation between the open and the closed feedback control circuits was 2.5%. There was no difference in pulse width and negligible difference in pulse frequency. Maximum value of backscattered radiation from the micro Multileaf collimator into the beam monitor chamber was found to be 0.5%.

  5. IVIDIL experiment onboard the ISS

    Science.gov (United States)

    Shevtsova, Valentina

    2010-09-01

    The experiment IVIDIL (Influence of Vibrations on Diffusion in Liquids) is scheduled to be performed in forthcoming fall 2009 onboard the ISS, inside the SODI instrument mounted in the Glovebox on the ESA Columbus module. It is planned to carry out 39 experimental runs with each of them lasting 18 h. The objective of the experiment is threefold. After each space experiment there is a discussion about the role of onboard g-jitters. One objective is to identify the limit level of vibrations below which g-jitter does not play a role for onboard experiments. This objective will be fulfilled by observing diffusive process under different imposed controlled vibrations. Second, to perform precise measurements of diffusion and thermodiffusion coefficients for two binary mixtures in the absence of buoyant convection. The measured values can be used as standards for ground experiments. Two aqueous solutions will be used as test fluids: two different concentrations of water-isopropanol (IPA) with positive and negative Soret effect. This objective also includes studying the influence of vibrations on the measured values of diffusion and thermodiffusion coefficients. Finally, to investigate vibration-induced convection and, particularly, heat and mass transfer under vibrations. Three International Teams are involved in the preparation of the experiment ( Shevtsova et al., 2007). ULB (MRC) is responsible for all aspects related to IVIDIL experimental definition, theoretical and numerical modeling and coordination of the entire project. Team from Ryerson University (led by Z. Saghir), Ontario, Canada and Russian team from Perm, ICMM UB RAS (led by T. Lyubimova) provide theoretical and numerical support. As being the coordinator, the author will present a general description of the experiment and outline some results obtained by MRC, ULB researchers only, i.e. by A. Mialdun, D. Melnikov, I. Ryzhkov, Yu. Gaponenko.

  6. Corona discharge ion mobility spectrometry with orthogonal acceleration time of flight mass spectrometry for monitoring of volatile organic compounds.

    Science.gov (United States)

    Sabo, Martin; Matejčík, Štefan

    2012-06-19

    We demonstrate the application of corona discharge ion mobility spectrometry with orthogonal acceleration time of flight mass spectrometry (CD IMS-oaTOF) for volatile organic compounds (VOCs) monitoring. Two-dimensional (2D) IMS-oaTOF spectra of VOCs were recorded in nearly real time. The corona discharge atmospheric pressure chemical ionization (APCI) source was operated in positive mode in nitrogen and air. The CD ion source generates in air H(3)O(+)(H(2)O)(n) and NO(+). The NO(+) offers additional possibility for selective ionization and for an increase of the sensitivity of monoaromatic compounds. In addition to H(3)O(+)(H(2)O)(n) and NO(+), we have carried out ionization of VOCs using acetone as dopant gas ((CH(3))(2)COH(+)). Sixteen model VOCs (tetrahydrofuran, butanol, n-propanol, iso-propano, acetone, methanol, ethanol, toluene, benzene, amomnia, dioxan, triethylamine, acetonitrile, formaldehyde, m-xylene, 2,2,2-trifluoroethylamine) were tested using these ionization techniques.

  7. Status of Higher Order Mode Beam Position Monitors in 3.9 GHz Superconducting Accelerating Cavities at FLASH

    CERN Document Server

    Zhang, P; Flisgen, T; van Rienen, U; Jones, R M; Shinton, I R R

    2013-01-01

    Higher order mode (HOM) beam position monitors (BPM) are being developed for the 3.9 GHz third harmonic superconducting accelerating cavities at FLASH. The transverse beam position in a cavity can be determined utilizing beam-excited HOMs based on dipole components. The existing couplers used for HOM suppression provide necessary signals. The diagnostics principle is similar to a cavity BPM, but requires no additional vacuum instruments on the linac. The challenges of HOM-BPM for 3.9 GHz cavities lie in the dense HOM spectrum arising from the coupling of the majority HOMs amongst the four cavities in the cryo-module ACC39. HOMs with particularly promising diagnostics features were evaluated using a spectrum analyzer and custom-built test electronics with various data analysis techniques, data reduction was focused on. After careful theoretical and experimental assessment of the HOM spectrum, multi-cavity modes in the region of 5 GHz were chosen to provide a global position over the complete module with superi...

  8. Status of higher order mode beam position monitors in 3.9 GHz superconducting accelerating cavities at FLASH

    CERN Document Server

    Zhang, P; Jones, R M; Flisgen, T; Van Rienen, U; Shinton, I R R

    2013-01-01

    Higher order mode (HOM) beam position monitors (BPM) are being developed for the 3.9 GHz third harmonic superconducting accelerating cavities at FLASH. The transverse beam position in a cavity can be determined utilizing beam-excited HOMs based on dipole components. The existing couplers used for HOM suppression provide necessary signals. The diagnostics principle is similar to a cavity BPM, but requires no additional vacuum instruments on the linac. The challenges of HOM-BPM for 3.9 GHz cavities lie in the dense HOM spectrum arising from the coupling of the majority HOMs amongst the four cavities in the cryo-module ACC39. HOMs with particularly promising diagnostics features were evaluated using a spectrum analyzer and custom-built test electronics with various data analysis techniques, data reduction was focused on. After careful theoretical and experimental assessment of the HOM spectrum, multi-cavity modes in the region of 5 GHz were chosen to provide a global position over the complete module with superi...

  9. Cardiac acceleration at the onset of exercise: a potential parameter for monitoring progress during physical training in sports and rehabilitation.

    Science.gov (United States)

    Hettinga, Florentina J; Monden, Paul G; van Meeteren, Nico L U; Daanen, Hein A M

    2014-05-01

    There is a need for easy-to-use methods to assess training progress in sports and rehabilitation research. The present review investigated whether cardiac acceleration at the onset of physical exercise (HRonset) can be used as a monitoring variable. The digital databases of Scopus and PubMed were searched to retrieve studies investigating HRonset. In total 652 studies were retrieved. These articles were then classified as having emphasis on HRonset in a sports or rehabilitation setting, which resulted in 8 of 112 studies with a sports application and 6 of 68 studies with a rehabilitation application that met inclusion criteria. Two co-existing mechanisms underlie HRonset: feedforward (central command) and feedback (mechanoreflex, metaboreflex, baroreflex) control. A number of studies investigated HRonset during the first few seconds of exercise (HRonsetshort), in which central command and the mechanoreflex determine vagal withdrawal, the major mechanism by which heart rate (HR) increases. In subsequent sports and rehabilitation studies, interest focused on HRonset during dynamic exercise over a longer period of time (HRonsetlong). Central command, mechanoreflexes, baroreflexes, and possibly metaboreflexes contribute to HRonset during the first seconds and minutes of exercise, which in turn leads to further vagal withdrawal and an increase in sympathetic activity. HRonset has been described as the increase in HR compared with resting state (delta HR) or by exponential modeling, with measurement intervals ranging from 0-4 s up to 2 min. Delta HR was used to evaluate HRonsetshort over the first 4 s of exercise, as well as for analyzing HRonsetlong. In exponential modeling, the HR response to dynamic exercise is biphasic, consisting of fast (parasympathetic, 0-10 s) and slow (sympathetic, 1-4 min) components. Although available studies differed largely in measurement protocols, cross-sectional and longitudinal training studies showed that studies analyzing HRonset

  10. SU-E-T-354: Efficient and Enhanced QA Testing of Linear Accelerators Using a Real-Time Beam Monitor

    Energy Technology Data Exchange (ETDEWEB)

    Jung, J; Farrokhkish, M; Norrlinger, B; Wang, Y [Princess Margaret Cancer Centre, Toronto, Ontario (Canada); Heaton, R; Jaffray, D; Islam, M [Princess Margaret Cancer Centre, Toronto, Ontario (Canada); University of Toronto, Toronto, Ontario (Canada)

    2015-06-15

    Purpose: To investigate the feasibility of performing routine QA tests of linear accelerators (Linac) using the Integral Quality Monitoring (IQM) system. The system, consisting of a 1-D sensitivity gradient large area ion-chamber mounted at the collimator, allows automatic collection and analysis of beam data. Methods: The IQM was investigated to perform several QA constancy tests, similar to those recommended by AAPM TG142, of a Linac including: beam output, MLC calibration, beam symmetry, relative dose factor (RDF), dose linearity, output as a function of gantry angle and dose rate. All measurements by the IQM system accompanied a reference measurement using a conventional dosimetry system and were performed on an Elekta Infinity Linac with Agility MLC. The MLC calibration check is done using a Picket-Fence type 2×10cm{sup 2} field positioned at different off-axis locations along the chamber gradient. Beam symmetry constancy values are established by signals from an 4×4cm{sup 2} aperture located at various off-axis positions; the sensitivity of the test was determined by the changes in the signals in response to a tilt in the beam. The data for various square field sizes were used to develop a functional relationship with RDF. Results: The IQM tracked the beam output well within 1% of the reference ion-chamber readings. The Picket-Fence type field test detected a 1mm shift error of one MLC bank. The system was able to detect 2.5% or greater beam asymmetry. The IQM results for all other QA tests were found to agree with the reference values to within 0.5%. Conclusion: It was demonstrated that the IQM system can effectively monitor the Linac performance parameters for the purpose of routine QA constancy tests. With minimum user interactions a comprehensive set of tests can be performed efficiently, allowing frequent monitoring of the Linac. The presenting author’s salary is funded by the manufacturer of the QA device. All the other authors have financial

  11. Evaluation of the environmental equivalent dose rate using area monitors for neutrons in clinical linear accelerators; Avaliacao da taxa de equivalente de dose ambiente utilizando monitores de area para neutrons em aceleradores lineares clinicos

    Energy Technology Data Exchange (ETDEWEB)

    Salgado, Ana Paula; Pereira, Walsan Wagner; Patrao, Karla C. de Souza; Fonseca, Evaldo S. da, E-mail: asalgado@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Batista, Delano V.S. [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil)

    2009-07-01

    The Neutron Laboratory of the Radioprotection and Dosimetry Institute - IRD/CNEN, Rio de Janeiro, Brazil, initiated studies on the process of calibration of neutron area monitors and the results of the measurements performed at radiotherapy treatment rooms, containing clinical accelerators

  12. Radiation dosimetry onboard the International Space Station ISS.

    Science.gov (United States)

    Berger, Thomas

    2008-01-01

    Besides the effects of the microgravity environment, and the psychological and psychosocial problems encountered in confined spaces, radiation is the main health detriment for long duration human space missions. The radiation environment encountered in space differs in nature from that on earth, consisting mostly of high energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones encountered on earth for occupational radiation workers. Therefore the determination and the control of the radiation load on astronauts is a moral obligation of the space faring nations. The requirements for radiation detectors in space are very different to that on earth. Limitations in mass, power consumption and the complex nature of the space radiation environment define and limit the overall construction of radiation detectors. Radiation dosimetry onboard the International Space Station (ISS) is onboard the International Space Station (ISS) is accomplished to one part as "operational" dosimetry accomplished to one part as "operational" dosimetry aiming for area monitoring of the radiation environment as well as astronaut surveillance. Another part focuses on "scientific" dosimetry aiming for a better understanding of the radiation environment and its constitutes. Various research activities for a more detailed quantification of the radiation environment as well as its distribution in and outside the space station have been accomplished in the last years onboard the ISS. The paper will focus on the current radiation detectors onboard the ISS, their results, as well as on future planned activities.

  13. Rapid Diagnostics of Onboard Sequences

    Science.gov (United States)

    Starbird, Thomas W.; Morris, John R.; Shams, Khawaja S.; Maimone, Mark W.

    2012-01-01

    Keeping track of sequences onboard a spacecraft is challenging. When reviewing Event Verification Records (EVRs) of sequence executions on the Mars Exploration Rover (MER), operators often found themselves wondering which version of a named sequence the EVR corresponded to. The lack of this information drastically impacts the operators diagnostic capabilities as well as their situational awareness with respect to the commands the spacecraft has executed, since the EVRs do not provide argument values or explanatory comments. Having this information immediately available can be instrumental in diagnosing critical events and can significantly enhance the overall safety of the spacecraft. This software provides auditing capability that can eliminate that uncertainty while diagnosing critical conditions. Furthermore, the Restful interface provides a simple way for sequencing tools to automatically retrieve binary compiled sequence SCMFs (Space Command Message Files) on demand. It also enables developers to change the underlying database, while maintaining the same interface to the existing applications. The logging capabilities are also beneficial to operators when they are trying to recall how they solved a similar problem many days ago: this software enables automatic recovery of SCMF and RML (Robot Markup Language) sequence files directly from the command EVRs, eliminating the need for people to find and validate the corresponding sequences. To address the lack of auditing capability for sequences onboard a spacecraft during earlier missions, extensive logging support was added on the Mars Science Laboratory (MSL) sequencing server. This server is responsible for generating all MSL binary SCMFs from RML input sequences. The sequencing server logs every SCMF it generates into a MySQL database, as well as the high-level RML file and dictionary name inputs used to create the SCMF. The SCMF is then indexed by a hash value that is automatically included in all command

  14. Differential-output B-dot and D-dot monitors for current and voltage measurements on a 20-MA, 3-MV pulsed-power accelerator

    Directory of Open Access Journals (Sweden)

    T. C. Wagoner

    2008-10-01

    Full Text Available We have developed a system of differential-output monitors that diagnose current and voltage in the vacuum section of a 20-MA 3-MV pulsed-power accelerator. The system includes 62 gauges: 3 current and 6 voltage monitors that are fielded on each of the accelerator’s 4 vacuum-insulator stacks, 6 current monitors on each of the accelerator’s 4 outer magnetically insulated transmission lines (MITLs, and 2 current monitors on the accelerator’s inner MITL. The inner-MITL monitors are located 6 cm from the axis of the load. Each of the stack and outer-MITL current monitors comprises two separate B-dot sensors, each of which consists of four 3-mm-diameter wire loops wound in series. The two sensors are separately located within adjacent cavities machined out of a single piece of copper. The high electrical conductivity of copper minimizes penetration of magnetic flux into the cavity walls, which minimizes changes in the sensitivity of the sensors on the 100-ns time scale of the accelerator’s power pulse. A model of flux penetration has been developed and is used to correct (to first order the B-dot signals for the penetration that does occur. The two sensors are designed to produce signals with opposite polarities; hence, each current monitor may be regarded as a single detector with differential outputs. Common-mode-noise rejection is achieved by combining these signals in a 50-Ω balun. The signal cables that connect the B-dot monitors to the balun are chosen to provide reasonable bandwidth and acceptable levels of Compton drive in the bremsstrahlung field of the accelerator. A single 50-Ω cable transmits the output signal of each balun to a double-wall screen room, where the signals are attenuated, digitized (0.5-ns/sample, numerically compensated for cable losses, and numerically integrated. By contrast, each inner-MITL current monitor contains only a single B-dot sensor. These monitors are fielded in opposite-polarity pairs. The two

  15. A Wire Position Monitor System for the 1.3 GHZ Tesla-Style Cryomodule at the Fermilab New-Muon-Lab Accelerator

    CERN Document Server

    Eddy, N; Prieto, P; Semenov, A; Voy, D C; Wendt, M

    2012-01-01

    The first cryomodule for the beam test facility at the Fermilab New-Muon-Lab building is currently under RF commissioning. Among other diagnostics systems, the transverse position of the helium gas return pipe with the connected 1.3 GHz SRF accelerating cavities is measured along the ~15 m long module using a stretched-wire position monitoring system. An overview of the wire position monitor system technology is given, along with preliminary results taken at the initial module cool down, and during further testing. As the measurement system offers a high resolution, we also discuss options for use as a vibration detector.

  16. Onboard Systems Record Unique Videos of Space Missions

    Science.gov (United States)

    2010-01-01

    Ecliptic Enterprises Corporation, headquartered in Pasadena, California, provided onboard video systems for rocket and space shuttle launches before it was tasked by Ames Research Center to craft the Data Handling Unit that would control sensor instruments onboard the Lunar Crater Observation and Sensing Satellite (LCROSS) spacecraft. The technological capabilities the company acquired on this project, as well as those gained developing a high-speed video system for monitoring the parachute deployments for the Orion Pad Abort Test Program at Dryden Flight Research Center, have enabled the company to offer high-speed and high-definition video for geosynchronous satellites and commercial space missions, providing remarkable footage that both informs engineers and inspires the imagination of the general public.

  17. An application of modern control theory to jet propulsion systems. [considering onboard computer

    Science.gov (United States)

    Merrill, W. C.

    1975-01-01

    The control of an airbreathing turbojet engine by an onboard digital computer is studied. The approach taken is to model the turbojet engine as a linear, multivariable system whose parameters vary with engine operating environment. From this model adaptive closed-loop or feedback control laws are designed and applied to the acceleration of the turbojet engine.

  18. Real Time On-line Space Research Laboratory Environment Monitoring with Off-line Trend and Prediction Analysis

    Science.gov (United States)

    Jules, Kenol; Lin, Paul P.

    2006-01-01

    One of the responsibilities of the NASA Glenn Principal Investigator Microgravity Services is to support NASA sponsored investigators in the area of reduced-gravity acceleration data analysis, interpretation and the monitoring of the reduced-gravity environment on-board various carriers. With the International Space Station currently operational, a significant amount of acceleration data is being down-linked and processed on ground for both the space station onboard environment characterization (and verification) and scientific experiments. Therefore, to help principal investigator teams monitor the acceleration level on-board the International Space Station to avoid undesirable impact on their experiment, when possible, the NASA Glenn Principal Investigator Microgravity Services developed an artificial intelligence monitoring system, which detects in near real time any change in the environment susceptible to affect onboard experiments. The main objective of the monitoring system is to help research teams identify the vibratory disturbances that are active at any instant of time onboard the International Space Station that might impact the environment in which their experiment is being conducted. The monitoring system allows any space research scientist, at any location and at any time, to see the current acceleration level on-board the Space Station via the World Wide Web. From the NASA Glenn s Exploration Systems Division web site, research scientists can see in near real time the active disturbances, such as pumps, fans, compressor, crew exercise, re-boost, extra-vehicular activity, etc., and decide whether or not to continue operating or stopping (or making note of such activity for later correlation with science results) their experiments based on the g-level associated with that specific event. A dynamic graphical display accessible via the World Wide Web shows the status of all the vibratory disturbance activities with their degree of confidence as well as

  19. Digibaro pressure instrument onboard the Phoenix Lander

    Science.gov (United States)

    Harri, A.-M.; Polkko, J.; Kahanpää, H. H.; Schmidt, W.; Genzer, M. M.; Haukka, H.; Savijarv1, H.; Kauhanen, J.

    2009-04-01

    The Phoenix Lander landed successfully on the Martian northern polar region. The mission is part of the National Aeronautics and Space Administration's (NASA's) Scout program. Pressure observations onboard the Phoenix lander were performed by an FMI (Finnish Meteorological Institute) instrument, based on a silicon diaphragm sensor head manufactured by Vaisala Inc., combined with MDA data processing electronics. The pressure instrument performed successfully throughout the Phoenix mission. The pressure instrument had 3 pressure sensor heads. One of these was the primary sensor head and the other two were used for monitoring the condition of the primary sensor head during the mission. During the mission the primary sensor was read with a sampling interval of 2 s and the other two were read less frequently as a check of instrument health. The pressure sensor system had a real-time data-processing and calibration algorithm that allowed the removal of temperature dependent calibration effects. In the same manner as the temperature sensor, a total of 256 data records (8.53 min) were buffered and they could either be stored at full resolution, or processed to provide mean, standard deviation, maximum and minimum values for storage on the Phoenix Lander's Meteorological (MET) unit.The time constant was approximately 3s due to locational constraints and dust filtering requirements. Using algorithms compensating for the time constant effect the temporal resolution was good enough to detect pressure drops associated with the passage of nearby dust devils.

  20. DARA vestibular equipment onboard MIR.

    Science.gov (United States)

    Hofmann, P; Kellig, A; Hoffmann, H U; Ruyters, G

    1998-01-01

    In space, the weightless environment provides a different stimulus to the otolith organs of the vestibular system, and the resulting signals no longer correspond with the visual and other sensory signals sent to the brain. This signal conflict causes disorientation. To study this and also to understand the vestibular adaptation to weightlessness, DARA has developed scientific equipment for vestibular and visuo-oculomotoric investigations. Especially, two video-oculography systems (monocular--VOG--and binocular--BIVOG, respectively) as well as stimuli such as an optokinetic stimulation device have successfully been employed onboard MIR in the frame of national and European missions since 1992. The monocular VOG was used by Klaus Flade during the MIR '92 mission, by Victor Polyakov during his record 15 months stay onboard MIR in 1993/94 as well as by Ulf Merbold during EUROMIR '94. The binocular version was used by Thomas Reiter and Sergej Avdeyev during the 6 months EUROMIR '95 mission. PIs of the various experiments include H. Scherer and A. Clarke (FU Berlin), M. Dieterichs and S. Krafczyk (LMU Munchen) from Germany as well as C.H. Markham and S.G. Diamond from the United States. Video-Oculography (VOG) is a technique for examining the function of the human balance system located in the inner ear (vestibular system) and the visio-oculomotor interactions of the vestibular organ. The human eye movements are measured, recorded and evaluated by state-of-the-art video techniques. The method was first conceived and designed at the Vestibular Research Laboratory of the ENT Clinic in Steglitz, FU Berlin (A. Clarke, H. Scherer). Kayser-Threde developed, manufactured and tested the facilities for space application under contract to DARA. Evaluation software was first provided by the ENT Clinic, Berlin, later by our subcontractor Sensomotoric Instruments (SMI), Teltow. Optokinetic hardware to support visuo-oculomotoric investigations, has been shipped to MIR for EUROMIR '95

  1. Observation of TGFs onboard "Vernov" satellite and TGEs in ground-based experiments

    Science.gov (United States)

    Bogomolov, Vitaly; Panasyuk, Mikhail; Svertilov, Sergey; Garipov, Gali; Iyudin, Anatoly; Klimov, Pavel; Morozenko, Violetta; Maximov, Ivan; Mishieva, Tatiana; Klimov, Stanislav; Pozanenko, Alexey; Rothkaehl, Hanna

    2016-04-01

    "Vernov" satellite with RELEC experiment on-board was launched on 2014 July, 8 into a polar solar-synchronous orbit. The payload includes DRGE gamma-ray spectrometer providing measurements in 10-3000 keV energy range with four detectors directed to atmosphere. Total area of DRGE detectors is ~500 cm2. The data were recorded both in monitoring and gamma by gamma modes with timing accuracy ~15 us. Several TGF candidates with 10-40 gammas in a burst with duration instruments on-board "Vernov" satellite shows the absence of significant electromagnetic pulses around correspondent time moments. Comparison with WWLLN lightning network data base also indicates that there were no thunderstorms connected with most of detected TGF candidates. Possible connection of these flashes with electron precipitations is discussed. Ground-based experiments, with similar gamma-spectrometers were conducted, to study the spectral, temporal and spatial characteristics of TGEs in 20-3000 keV energy range, as well, as to search the fast hard X-ray and gamma-ray flashes possibly appearing at the moment of lightning. The time of each gamma-quantum interaction was recorded with an ~15 us s accuracy together with detailed spectral data. Measurements were done on the ground at Moscow region, and at mountain altitude in Armenia at Aragatz station. During the time interval covering spring, summer and autumn of 2015 a number of TGEs were detected. Measured low-energy gamma-ray spectra usually contain a set of lines that can be interpreted as radiation of Rn-222 daughter isotopes. The increase of Rn-222 radiation was detected during rainfalls with thunderstorm, as well, as during rainy weather without thunderstorms. Variations of Rn-222 radiation dominate at low energies (measure low energy gamma-radiation from the electrons accelerated in thunderclouds. There were no significant flashes with duration of ~1ms detected in coincidence with a nearby lightnings.

  2. Successful Application of Neutron Bubble Detectors in Neutron Dose Monitoring for Primus-M Election Linear Accelerators

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Neutrons produced by 10 MeV medical electronic linear accelerators used for radiotherapy treatments may be harmful for medical personnel and patients. These neutrons are generated by the photon-induced

  3. Onboard Short Term Plan Viewer

    Science.gov (United States)

    Hall, Tim; LeBlanc, Troy; Ulman, Brian; McDonald, Aaron; Gramm, Paul; Chang, Li-Min; Keerthi, Suman; Kivlovitz, Dov; Hadlock, Jason

    2011-01-01

    Onboard Short Term Plan Viewer (OSTPV) is a computer program for electronic display of mission plans and timelines, both aboard the International Space Station (ISS) and in ISS ground control stations located in several countries. OSTPV was specifically designed both (1) for use within the limited ISS computing environment and (2) to be compatible with computers used in ground control stations. OSTPV supplants a prior system in which, aboard the ISS, timelines were printed on paper and incorporated into files that also contained other paper documents. Hence, the introduction of OSTPV has both reduced the consumption of resources and saved time in updating plans and timelines. OSTPV accepts, as input, the mission timeline output of a legacy, print-oriented, UNIX-based program called "Consolidated Planning System" and converts the timeline information for display in an interactive, dynamic, Windows Web-based graphical user interface that is used by both the ISS crew and ground control teams in real time. OSTPV enables the ISS crew to electronically indicate execution of timeline steps, launch electronic procedures, and efficiently report to ground control teams on the statuses of ISS activities, all by use of laptop computers aboard the ISS.

  4. Autonomous operations through onboard artificial intelligence

    Science.gov (United States)

    Sherwood, R. L.; Chien, S.; Castano, R.; Rabideau, G.

    2002-01-01

    The Autonomous Sciencecraft Experiment (ASE) will fly onboard the Air Force TechSat 21 constellation of three spacecraft scheduled for launch in 2006. ASE uses onboard continuous planning, robust task and goal-based execution, model-based mode identification and reconfiguration, and onboard machine learning and pattern recognition to radically increase science return by enabling intelligent downlink selection and autonomous retargeting. Demonstration of these capabilities in a flight environment will open up tremendous new opportunities in planetary science, space physics, and earth science that would be unreachable without this technology.

  5. On-board Data Mining

    Science.gov (United States)

    Tanner, Steve; Stein, Cara; Graves, Sara J.

    Networks of remote sensors are becoming more common as technology improves and costs decline. In the past, a remote sensor was usually a device that collected data to be retrieved at a later time by some other mechanism. This collected data were usually processed well after the fact at a computer greatly removed from the in situ sensing location. This has begun to change as sensor technology, on-board processing, and network communication capabilities have increased and their prices have dropped. There has been an explosion in the number of sensors and sensing devices, not just around the world, but literally throughout the solar system. These sensors are not only becoming vastly more sophisticated, accurate, and detailed in the data they gather but they are also becoming cheaper, lighter, and smaller. At the same time, engineers have developed improved methods to embed computing systems, memory, storage, and communication capabilities into the platforms that host these sensors. Now, it is not unusual to see large networks of sensors working in cooperation with one another. Nor does it seem strange to see the autonomous operation of sensorbased systems, from space-based satellites to smart vacuum cleaners that keep our homes clean and robotic toys that help to entertain and educate our children. But access to sensor data and computing power is only part of the story. For all the power of these systems, there are still substantial limits to what they can accomplish. These include the well-known limits to current Artificial Intelligence capabilities and our limited ability to program the abstract concepts, goals, and improvisation needed for fully autonomous systems. But it also includes much more basic engineering problems such as lack of adequate power, communications bandwidth, and memory, as well as problems with the geolocation and real-time georeferencing required to integrate data from multiple sensors to be used together.

  6. Hubble space telescope onboard battery performance

    Science.gov (United States)

    Rao, Gopalakrishna M.; Wajsgras, Harry; Vaidyanathan, Hari; Armontrout, Jon D.

    1996-01-01

    The performance of six 88 Ah Nickel-Hydrogen (Ni-H2) batteries that are used onboard in the Hubble Space Telescope (Flight Spare Module (FSM) and Flight Module 2 (FM2)) is discussed. These batteries have 22 series cells per battery and a common bus that would enable them to operate at a common voltage. It is launched on April 24, 1990. This paper reviews: the cell design, battery specification, system constraints, operating parameters, onboard battery management, and battery performance.

  7. The onboard control system of "Navigator" platform

    Science.gov (United States)

    Syrov, A. S.; Smirnov, V. V.; Sokolov, V. N.; Iodko, G. S.; Mischikhin, V. V.; Kosobokov, V. N.; Shatskii, M. A.; Dobrynin, D. A.

    2016-12-01

    A brief description of the design concept, structure and performance of the onboard control system (AOCS) of the "Navigator" satellite platform, on the basis of which the spacecraft "Electro-L' and "Spektr-R" are designed, is presented. The test-flight results of the AOCS attitude accuracy are given. Approaches to the further development of the onboard control equipment for advanced spacecraft are determined and presented.

  8. Uav Onboard GPS in Positioning Determination

    Science.gov (United States)

    Tahar, K. N.; Kamarudin, S. S.

    2016-06-01

    The establishment of ground control points is a critical issue in mapping field, especially for large scale mapping. The fast and rapid technique for ground control point's establishment is very important for small budget projects. UAV onboard GPS has the ability to determine the point positioning. The objective of this research is to assess the accuracy of unmanned aerial vehicle onboard global positioning system in positioning determination. Therefore, this research used UAV onboard GPS as an alternative to determine the point positioning at the selected area. UAV is one of the powerful tools for data acquisition and it is used in many applications all over the world. This research concentrates on the error contributed from the UAV onboard GPS during observation. There are several points that have been used to study the pattern of positioning error. All errors were analyzed in world geodetic system 84- coordinate system, which is the basic coordinate system used by the global positioning system. Based on this research, the result of UAV onboard GPS positioning could be used in ground control point establishment with the specific error. In conclusion, accurate GCP establishment could be achieved using UAV onboard GPS by applying a specific correction based on this research.

  9. Alternative uses of a megavolt tandem accelerator for few-keV studies with ion-source SIMS monitoring

    Science.gov (United States)

    Mello, S. L. A.; Codeço, C. F. S.; Magnani, B. F.; Sant'Anna, M. M.

    2016-06-01

    We increase the versatility of a tandem electrostatic accelerator by implementing simple modifications to the standard operation procedure. While keeping its ability to deliver MeV ion beams, we show that the experimental setup can (i) provide good quality ion beams in the few-keV energy range and (ii) be used to study ion-beam surface modification with simultaneous secondary ion mass spectrometry. This latter task is accomplished without using any chamber connected to the accelerator exit. We perform mass spectrometry of the few-keV anions produced in the ion source by measuring their neutral counterparts at the accelerator exit with energies up to 1.7 MeV. With an additional modification, a high-current few-keV regime is obtained, using the ion source as an irradiation chamber and the accelerator itself only as a mass spectrometer. As an example of application, we prepare a sample for the study of ion-beam assisted dewetting of a thin Au film on a Si substrate.

  10. Development of a Compton Camera for Online Range Monitoring of Laser-Accelerated Proton Beams via Prompt-Gamma Detection

    NARCIS (Netherlands)

    Thirolf, P.G.; Lang, C.; Aldawood, S.; Van der Kolff, H.G.; Maier, L.; Schaart, D.R.; Parodi, K.

    2014-01-01

    Presently large efforts are conducted in Munich towards the development of proton beams for bio-medical applications, generated via the technique of particle acceleration from high-power, short-pulse lasers. While so far mostly offline diagnostics tools are used in this context, we aim at developing

  11. Spectrally and Radiometrically Stable, Wideband, Onboard Calibration Source

    Science.gov (United States)

    Coles, James B.; Richardson, Brandon S.; Eastwood, Michael L.; Sarture, Charles M.; Quetin, Gregory R.; Porter, Michael D.; Green, Robert O.; Nolte, Scott H.; Hernandez, Marco A.; Knoll, Linley A.

    2013-01-01

    The Onboard Calibration (OBC) source incorporates a medical/scientific-grade halogen source with a precisely designed fiber coupling system, and a fiber-based intensity-monitoring feedback loop that results in radiometric and spectral stabilities to within less than 0.3 percent over a 15-hour period. The airborne imaging spectrometer systems developed at the Jet Propulsion Laboratory incorporate OBC sources to provide auxiliary in-use system calibration data. The use of the OBC source will provide a significant increase in the quantitative accuracy, reliability, and resulting utility of the spectral data collected from current and future imaging spectrometer instruments.

  12. On-Orbit Performance of MODIS On-Board Calibrators

    Science.gov (United States)

    Xiong, X.; Che, N.; Chiang, K.; Esposito, J.; Barnes, William; Guenther, B.; Zukor, Dorothy J. (Technical Monitor)

    2001-01-01

    The Terra MODIS (Moderate Resolution Imaging Spectroradiometer) was launched on December 18, 1999 and acquired the first scene data on February 24, 2000. It has 36 spectral bands covering spectral range from 0.41 to 14.2 microns and provides spatial resolutions of 250 (2 bands), 500 (5 bands), and 1000 m at Nadir. The instrument on-orbit calibration and characterization are determined and monitored through the use of a number of on-board calibrators (OBC). Radiometric calibration for the reflective solar bands (B1-B19, B26), from VIS (visible) to SWIR (short wavelength infrared) (0.41 to 2.1 microns), uses a Spectralon (tm) solar diffuser (SD) and a solar diffuser stability monitor (SDSM). For the thermal emissive bands (B20-B25, B27-B36), from MWIR (medium wavelength infrared) to LWIR (long wavelength infrared) (3.75 to 14.2 micron), a V-grooved flat panel blackbody is used. The instrument spectral for the VIS to SWIR bands and spatial co-registration characterizations for all bands are monitored on-orbit by the spectral radiometric calibration assembly (SRCA). In this report, we discuss the application and performance of the key MODIS on-board calibrators and their impacts on the instrument system calibration and characterization.

  13. 47 CFR 80.1179 - On-board repeater limitations.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false On-board repeater limitations. 80.1179 Section... On-board repeater limitations. When an on-board repeater is used, the following limitations must be met: (a) The on-board repeater antenna must be located no higher than 3 meters (10 feet) above...

  14. Development of a Wireless Displacement Measurement System Using Acceleration Responses

    Directory of Open Access Journals (Sweden)

    Billie F. Spencer Jr.

    2013-07-01

    Full Text Available Displacement measurements are useful information for various engineering applications such as structural health monitoring (SHM, earthquake engineering and system identification. Most existing displacement measurement methods are costly, labor-intensive, and have difficulties particularly when applying to full-scale civil structures because the methods require stationary reference points. Indirect estimation methods converting acceleration to displacement can be a good alternative as acceleration transducers are generally cost-effective, easy to install, and have low noise. However, the application of acceleration-based methods to full-scale civil structures such as long span bridges is challenging due to the need to install cables to connect the sensors to a base station. This article proposes a low-cost wireless displacement measurement system using acceleration. Developed with smart sensors that are low-cost, wireless, and capable of on-board computation, the wireless displacement measurement system has significant potential to impact many applications that need displacement information at multiple locations of a structure. The system implements an FIR-filter type displacement estimation algorithm that can remove low frequency drifts typically caused by numerical integration of discrete acceleration signals. To verify the accuracy and feasibility of the proposed system, laboratory tests are carried out using a shaking table and on a three storey shear building model, experimentally confirming the effectiveness of the proposed system.

  15. Implementing Temperature Supervision for the ALICE CRU Card Using the Onboard Microcontroller

    CERN Document Server

    Perez Bernabeu, Ruben

    2017-01-01

    We report on the first implementation of the thermal supervisory firmware for the onboard microcontroller on the ALICE CRU card. The Common Readout Unit (CRU) is a custom PCI Express FPGA card developed by “Centre Physique des Particules de Marseille” in collaboration of LHCb and ALICE. While the main effort has been focused on the development of the FPGA firmware that implements all the communication needs, there are several independent design tasks identified to ensure the safe operation of the CRU card under all possible conditions. One such task is to implement a robust local (on-board) temperature monitoring and safeguarding subsystem based on ATmega128 microcontroller. It will autonomously prevent the thermal damage of the card even if the remote HW monitoring and controlling functions (integrated in DCS) failed for any reason. Consequently, our main goal in this project will be implementing the temperature supervision using the onboard microcontroller.

  16. Onboard tagging for smart medical devices.

    Science.gov (United States)

    Li, Kejia; Warren, Steve

    2011-01-01

    Most medical devices are 'dumb:' their role is to acquire, display, and forward data. They make few if any operational decisions based on those data. Onboard tagging is a means whereby a device can embed information about itself, its data, and the sensibility of those data into its data stream. This diagnostic add-on offers a move toward 'smart' devices that will have the ability to affect changes in operational modes based on onboard contextual decision making, such as decisions to avoid needless wireless transmission of corrupt data. This paper presents a description of three types of onboard tags that relate to device hardware (type I tag), signal statistics (type II tag), and signal viability for the intended application (type III tag). A custom wireless pulse oximeter is presented as a use case to show how type II and III tags that convey photoplethysmogram (PPG) statistics and usability specifiers can be calculated and embedded into the data stream without degrading performance.

  17. Forbush decrease effects on radiation dose received on-board aeroplanes.

    Science.gov (United States)

    Lantos, P

    2005-01-01

    Doses received on-board aeroplanes during deep Forbush decreases (FDs) have been recently measured and published. Using an operational model of dose calculation, the effects on aviation dose of the FDs observed from 1981 to 2003 using neutron monitors are studied and a simplified method to estimate dose variations from galactic cosmic ray variations during FDs is derived.

  18. Using Onboard Telemetry for MAVEN Orbit Determination

    Science.gov (United States)

    Lam, Try; Trawny, Nikolas; Lee, Clifford

    2013-01-01

    Determination of the spacecraft state has been traditional done using radiometric tracking data before and after the atmosphere drag pass. This paper describes our approach and results to include onboard telemetry measurements in addition to radiometric observables to refine the reconstructed trajectory estimate for the Mars Atmosphere and Volatile Evolution Mission (MAVEN). Uncertainties in the Mars atmosphere models, combined with non-continuous tracking degrade navigation accuracy, making MAVEN a key candidate for using onboard telemetry data to help complement its orbit determination process.

  19. Nondestructive Evaluation and Monitoring Results from COPV Accelerated Stress Rupture Testing, NASA White Sands Test Facility (WSTF)

    Science.gov (United States)

    Saulsberry Regor

    2010-01-01

    Develop and demonstrate NDE techniques for real-time characterization of CPVs and, where possible, identification of NDE capable of assessing stress rupture related strength degradation and/or making vessel life predictions (structural health monitoring or periodic inspection modes). Secondary: Provide the COPV user and materials community with quality carbon/epoxy (C/Ep) COPV stress rupture progression rate data. Aid in modeling, manufacturing, and application of COPVs for NASA spacecraft.

  20. Monitor backscatter factors for the Varian 21EX and TrueBeam linear accelerators: measurements and Monte Carlo modeling

    CERN Document Server

    Zavgorodni, Sergei; Townson, Reid

    2013-01-01

    Objectives: Linac backscattered radiation (BSR) into the monitor chamber affects the chamber signal and has to be accounted for in radiotherapy dose calculations. In Monte Carlo (MC) calculations BSR can be modeled explicitly and incorporated into absolute dose. However, explicit modeling of BSR becomes impossible if treatment head geometry is not available. In this study, monitor backscatter factors (MBSFs), defined as the ratio of the charge collected in the monitor chamber for a reference field to that of a given field, have been evaluated experimentally and incorporated into MC modeling. Materials and methods: A telescopic technique similar to that by Kubo (1989) was used. However, instead of lead slits, a 1.8 mm diameter collimator and a PTW pinpoint ionization chamber positioned at extended SDD were used. These provided a field of view to the source of less than 3.1 mm. MBSFs were also explicitly modeled in MC calculations using BEAMnrc and DOSXYZnrc codes for 6MV and 18MV beams of a Varian 21EX linac, ...

  1. An Onboarding Program for the CT Department.

    Science.gov (United States)

    Baldwin, Brandi

    2016-01-01

    Healthcare organizations compete for employees in the same way television networks compete for new talent. Organizations also compete over experience, knowledge, and skills new employees bring with them. Organizations that can acclimate a new employee into the social and performance aspects of a new job the quickest create a substantial competitive advantage. Onboarding is the term used for orientation or organizational socialization where new employees acquire the necessary knowledge, skills, and behaviors to fit in with a new company. Computed tomography (CT) department specific onboarding programs increase the comfort level of new employees by informing them of the supervisor's and the department's expectations. Although this article discusses CT, specifically, an onboarding program could apply to all of imaging. With the high costs that employee turnover incurs, all departments should have an orientation program that helps retain employees as well as prepare new employees for employment. Current personnel are valuable resources for offering appropriate information for successful employment in specific departments. A structured, department specific onboarding program with the full participation and support of current staff will enhance staff retention.

  2. Demonstration of a real-time interferometer as a bunch-lenght monitor in a high-current electron beam accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Thangaraj, J.; Thurman-Keup, R.; Ruan, J.; Johnson, A.S.; Lumpkin, A; Santucci, J.; Maxwell, T.; /Fermilab; Andonian, G.; /UCLA /RadiaBeam Tech.; Murokh, A.; Ruelas, M.; Ovodenko, A.; /RadiaBeam Tech.

    2012-03-01

    A real-time interferometer (RTI) has been developed to monitor the bunch length of an electron beam in an accelerator. The RTI employs spatial autocorrelation, reflective optics, and a fast response pyro-detector array to obtain a real-time autocorrelation trace of the coherent radiation from an electron beam thus providing the possibility of online bunch-length diagnostics. A complete RTI system has been commissioned at the A0 photoinjector facility to measure sub-mm bunches at 13 MeV. Bunch length variation (FWHM) between 0.8 ps (-0.24 mm) and 1.5 ps (-0.45 mm) has been measured and compared with a Martin-Puplett interferometer and a streak camera. The comparisons show that RTI is a viable, complementary bunch length diagnostic for sub-mm electron bunches.

  3. First simultaneous measurement of sextupolar and octupolar resonance driving terms in a circular accelerator from turn-by-turn beam position monitors data

    CERN Document Server

    Franchi, A; Ewald, F; Bec, G Le; Scheidt, K B

    2014-01-01

    Beam lifetime in storage rings and colliders is affected by, among other effects, lattice nonlinearities. Their control are of great benefit to the dynamic aperture of an accelerator, whose enlargement leads in general to more efficient injection and longer lifetime. This article describes a procedure to evaluate and correct unwanted nonlinearities by using turn-by-turn beam position monitor data, which is an evolution of previous works on the resonance driving terms (RDTs). Effective sextupole magnetic errors and tilts at the ESRF electron storage ring are evaluated and corrected (when possible) by using this technique. For the first time, also octupolar RDTs could be measured and used to define an octupolar model for the main quadrupoles. Most of the deviations from the model observed in the sextupolar RDTs of the ESRF storage ring turned out to be generated by focusing errors rather than by sextupole errors. These results could be achieved thanks to new analytical formulas describing the harmonic content o...

  4. Performance of a Downconverter Test-electronics with MTCA-based Digitizers for Beam Position Monitoring in 3.9 GHz Accelerating Cavities

    CERN Document Server

    Wamsat, T; Lorbeer, B; Zhang, P

    2012-01-01

    Beam-excited higher order modes (HOM) in 3.9GHz accelerating cavities are planned to be used for beam position monitoring at the European XFEL. The selected HOMs are located around 5440MHz, with a bandwidth of 100MHz and 9060MHz, with a bandwidth of 50MHz. A downconverter electronics, built for tests at FLASH, converts the HOMs to an intermediate frequency of 70MHz. The MTCA (Micro Telecommunications Computing Architecture) standard will be used for the XFEL. Thus it is important to have a performance study of the downconverter test-electronics using the MTCA digitizer card SIS8300. In the digitizer the IF frequency of 70MHz is undersampled with a clock frequency of 108MS/s. The paper presents the performance of the digitizer together with the test-electronics. A comparison with a 216MS/s VME (Versa Module Eurocard) digitizer is made.

  5. Airbreathing Acceleration Toward Earth Orbit

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, J C

    2007-05-09

    As flight speed increases, aerodynamic drag rises more sharply than the availability of atmospheric oxygen. The ratio of oxygen mass flux to dynamic pressure cannot be improved by changing altitude. The maximum possible speed for airbreathing propulsion is limited by the ratio of air capture area to vehicle drag area, approximately Mach 6 at equal areas. Simulation of vehicle acceleration shows that the use of atmospheric oxygen offers a significant potential for minimizing onboard consumables at low speeds. These fundamental calculations indicate that a practical airbreathing launch vehicle would accelerate to near steady-state speed while consuming only onboard fuel, then transition to rocket propulsion. It is suggested that an aircraft carrying a rocket-propelled vehicle to approximately Mach 5 could be a realistic technical goal toward improving access to orbit.

  6. A new on-board imaging treatment technique for palliative and emergency treatments in radiation oncology

    Energy Technology Data Exchange (ETDEWEB)

    Held, Mareike

    2016-03-23

    This dissertation focuses on the use of on-board imaging systems as the basis for treatment planning, presenting an additional application for on-board images. A clinical workflow is developed to simulate, plan, and deliver a simple radiation oncology treatment rapidly, using 3D patient scans. The work focuses on an on-line dose planning and delivery process based on on-board images entirely performed with the patient set up on the treatment couch of the linear accelerator. This potentially reduces the time between patient simulation and treatment to about 30 minutes. The basis for correct dose calculation is the accurate image gray scale to tissue density calibration. The gray scale, which is defined in CT Numbers, is dependent on the energy spectrum of the beam. Therefore, an understanding of the physics characteristics of each on-board system is required to evaluate the impact on image quality, especially regarding the underlying cause of image noise, contrast, and non-uniformity. Modern on-board imaging systems, including kV and megavoltage (MV) cone beam (CB) CT as well as MV CT, are characterized in terms of image quality and stability. A library of phantom and patient CT images is used to evaluate the dose calculation accuracy for the on-board images. The dose calculation objective is to stay within 5% local dose differences compared to standard kV CT dose planning. The objective is met in many treatment cases. However, dose calculation accuracy depends on the anatomical treatment site. While on-board CT-based treatments of the head and extremities are predictable within 5% on all systems, lung tissue and air cavities may create local dose discrepancies of more than 5%. The image quality varies between the tested units. Consequently, the CT number-to-density calibration is defined independently for each system. In case of some imaging systems, the CT numbers of the images are dependent on the protocol used for on-board imaging, which defines the imaging dose

  7. Wide dynamic range FPGA-based TDC for monitoring a trigger timing distribution system in linear accelerators

    Science.gov (United States)

    Suwada, T.; Miyahara, F.; Furukawa, K.; Shoji, M.; Ikeno, M.; Tanaka, M.

    2015-06-01

    A new field-programmable gate array (FPGA)-based time-to-digital converter (TDC) with a wide dynamic range greater than 20 ms has been developed to monitor the timing of various pulsed devices in the trigger timing distribution system of the KEKB injector linac for the Super KEK B-factory project. The pulsed devices are driven by feeding regular as well as any irregular (or event-based) timing pulses. The timing pulses are distributed to these pulsed devices along the linac beam line with fiber-optic links on the basis of the parameters to be set pulse-by-pulse in the event-based timing and control system within 20 ms. For monitoring the timing as precisely as possible, a 16-ch FPGA-based TDC has been developed on a Xilinx Spartan-6 FPGA equipped on VME board with a resolution of 1 ns. The resolution was achieved by applying a multisampling technique, and the accuracies were 2.6 ns (rms) and less than 1 ns (rms) within the dynamic ranges of 20 ms and 7.5 ms, respectively. The various nonlinear effects were improved by implementing a high-precision external clock with a built-in temperature-compensated crystal oscillator.

  8. Wide dynamic range FPGA-based TDC for monitoring a trigger timing distribution system in linear accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Suwada, T., E-mail: tsuyoshi.suwada@kek.jp [Accelerator Laboratory, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Department of Accelerator Science, Graduate University for Advanced Studies (SOKENDAI), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Miyahara, F.; Furukawa, K. [Accelerator Laboratory, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Department of Accelerator Science, Graduate University for Advanced Studies (SOKENDAI), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Shoji, M.; Ikeno, M.; Tanaka, M. [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)

    2015-06-21

    A new field-programmable gate array (FPGA)-based time-to-digital converter (TDC) with a wide dynamic range greater than 20 ms has been developed to monitor the timing of various pulsed devices in the trigger timing distribution system of the KEKB injector linac for the Super KEK B-factory project. The pulsed devices are driven by feeding regular as well as any irregular (or event-based) timing pulses. The timing pulses are distributed to these pulsed devices along the linac beam line with fiber-optic links on the basis of the parameters to be set pulse-by-pulse in the event-based timing and control system within 20 ms. For monitoring the timing as precisely as possible, a 16-ch FPGA-based TDC has been developed on a Xilinx Spartan-6 FPGA equipped on VME board with a resolution of 1 ns. The resolution was achieved by applying a multisampling technique, and the accuracies were 2.6 ns (rms) and less than 1 ns (rms) within the dynamic ranges of 20 ms and 7.5 ms, respectively. The various nonlinear effects were improved by implementing a high-precision external clock with a built-in temperature-compensated crystal oscillator.

  9. Formation Flight of Multiple UAVs via Onboard Sensor Information Sharing

    Directory of Open Access Journals (Sweden)

    Chulwoo Park

    2015-07-01

    Full Text Available To monitor large areas or simultaneously measure multiple points, multiple unmanned aerial vehicles (UAVs must be flown in formation. To perform such flights, sensor information generated by each UAV should be shared via communications. Although a variety of studies have focused on the algorithms for formation flight, these studies have mainly demonstrated the performance of formation flight using numerical simulations or ground robots, which do not reflect the dynamic characteristics of UAVs. In this study, an onboard sensor information sharing system and formation flight algorithms for multiple UAVs are proposed. The communication delays of radiofrequency (RF telemetry are analyzed to enable the implementation of the onboard sensor information sharing system. Using the sensor information sharing, the formation guidance law for multiple UAVs, which includes both a circular and close formation, is designed. The hardware system, which includes avionics and an airframe, is constructed for the proposed multi-UAV platform. A numerical simulation is performed to demonstrate the performance of the formation flight guidance and control system for multiple UAVs. Finally, a flight test is conducted to verify the proposed algorithm for the multi-UAV system.

  10. Formation Flight of Multiple UAVs via Onboard Sensor Information Sharing.

    Science.gov (United States)

    Park, Chulwoo; Cho, Namhoon; Lee, Kyunghyun; Kim, Youdan

    2015-07-17

    To monitor large areas or simultaneously measure multiple points, multiple unmanned aerial vehicles (UAVs) must be flown in formation. To perform such flights, sensor information generated by each UAV should be shared via communications. Although a variety of studies have focused on the algorithms for formation flight, these studies have mainly demonstrated the performance of formation flight using numerical simulations or ground robots, which do not reflect the dynamic characteristics of UAVs. In this study, an onboard sensor information sharing system and formation flight algorithms for multiple UAVs are proposed. The communication delays of radiofrequency (RF) telemetry are analyzed to enable the implementation of the onboard sensor information sharing system. Using the sensor information sharing, the formation guidance law for multiple UAVs, which includes both a circular and close formation, is designed. The hardware system, which includes avionics and an airframe, is constructed for the proposed multi-UAV platform. A numerical simulation is performed to demonstrate the performance of the formation flight guidance and control system for multiple UAVs. Finally, a flight test is conducted to verify the proposed algorithm for the multi-UAV system.

  11. Onboard autonomy on the Three Corner Sat Mission

    Science.gov (United States)

    Chien, S.; Engelhardt, B.; Knight, R.; Rabideau, G.; Sherwood, R.

    2001-01-01

    Three Corner Sat (3CS) is a mission of three university nanosatellites scheduled for launch on September 2002. The 3CS misison will utilize significan onboard autonomy to perform onboard science data validation and replanning.

  12. Monitor backscatter factors for the Varian 21EX and TrueBeam linear accelerators: measurements and Monte Carlo modelling.

    Science.gov (United States)

    Zavgorodni, Sergei; Alhakeem, Eyad; Townson, Reid

    2014-02-21

    Linac backscattered radiation (BSR) into the monitor chamber affects the chamber's signal and has to be accounted for in radiotherapy dose calculations. In Monte Carlo (MC) calculations, the BSR can be modelled explicitly and accounted for in absolute dose. However, explicit modelling of the BSR becomes impossible if treatment head geometry is not available. In this study, monitor backscatter factors (MBSFs), defined as the ratio of the charge collected in the monitor chamber for a reference field to that of a given field, have been evaluated experimentally and incorporated into MC modelling of linacs with either known or unknown treatment head geometry. A telescopic technique similar to that by Kubo (1989 Med. Phys. 16 295-98) was used. However, instead of lead slits, a 1.8 mm diameter collimator and a small (2 mm diameter) detector positioned at extended source to detector distance were used. This setup provided a field of view to the source of less than 3.1 mm and allowed for MBSF measurements of open fields from 1 × 1 to 40 × 40 cm(2). For the fields with both X and Y dimensions exceeding 15 cm, a diode detector was used. A pinpoint ionization chamber was used for smaller fields. MBSFs were also explicitly modelled in MC calculations using BEAMnrc and DOSXYZnrc codes for 6 and 18 MV beams of a Varian 21EX linac. A method for deriving the D(ch)(forward) values that are used in MC absolute dose calculations was demonstrated. These values were derived from measured MBSFs for two 21EX and four TrueBeam energies. MBSFs were measured for 6 and 18 MV beams from Varian 21EX, and for 6 MV, 10 MV-FFF, 10 MV, and 15 MV beams from Varian TrueBeam linacs. For the open field sizes modelled in this study for the 21EX, the measured MBSFs agreed with MC calculated values within combined statistical (0.4%) and experimental (0.2%) uncertainties. Variation of MBSFs across field sizes was about a factor of two smaller for the TrueBeam compared to 21EX Varian linacs. Measured

  13. Monitoring Activity for Recognition of Illness in Experimentally Infected Weaned Piglets Using Received Signal Strength Indication ZigBee-based Wireless Acceleration Sensor.

    Science.gov (United States)

    Ahmed, Sonia Tabasum; Mun, Hong-Seok; Islam, Md Manirul; Yoe, Hyun; Yang, Chul-Ju

    2016-01-01

    In this experiment, we proposed and implemented a disease forecasting system using a received signal strength indication ZigBee-based wireless network with a 3-axis acceleration sensor to detect illness at an early stage by monitoring movement of experimentally infected weaned piglets. Twenty seven piglets were divided into control, Salmonella enteritidis (SE) infection, and Escherichia coli (EC) infection group, and their movements were monitored for five days using wireless sensor nodes on their backs. Data generated showed the 3-axis movement of piglets (X-axis: left and right direction, Y-axis: anteroposterior direction, and Z-axis: up and down direction) at five different time periods. Piglets in both infected groups had lower weight gain and feed intake, as well as higher feed conversion ratios than the control group (p<0.05). Infection with SE and EC resulted in reduced body temperature of the piglets at day 2, 4, and 5 (p<0.05). The early morning X-axis movement did not differ between groups; however, the Y-axis movement was higher in the EC group (day 1 and 2), and the Z-axis movement was higher in the EC (day 1) and SE group (day 4) during different experimental periods (p<0.05). The morning X and Y-axis movement did not differ between treatment groups. However, the Z-axis movement was higher in both infected groups at day 1 and lower at day 4 compared to the control (p<0.05). The midday X-axis movement was significantly lower in both infected groups (day 4 and 5) compared to the control (p<0.05), whereas the Y-axis movement did not differ. The Z-axis movement was highest in the SE group at day 1 and 2 and lower at day 4 and 5 (p<0.05). Evening X-axis movement was highest in the control group throughout the experimental period. During day 1 and 2, the Z-axis movement was higher in both of the infected groups; whereas it was lower in the SE group during day 3 and 4 (p<0.05). During day 1 and 2, the night X-axis movement was lower and the Z-axis movement

  14. Two Years Onboard the MER Opportunity Rover

    Science.gov (United States)

    Estlin, Tara; Anderson, Robert C.; Bornstein, Benjamin; Burl, Michael; Castano, Rebecca; Gaines, Daniel; Judd, Michele; Thompson, David R.

    2012-01-01

    The Autonomous Exploration for Gathering Increased Science (AEGIS) system provides automated data collection for planetary rovers. AEGIS is currently being used onboard the Mars Exploration Rover (MER) mission's Opportunity to provide autonomous targeting of the MER Panoramic camera. Prior to AEGIS, targeted data was collected in a manual fashion where targets were manually identified in images transmitted to Earth and the rover had to remain in the same location for one to several communication cycles. AEGIS enables targeted data to be rapidly acquired with no delays for ground communication. Targets are selected by AEGIS through the use of onboard data analysis techniques that are guided by scientist-specified objectives. This paper provides an overview of the how AEGIS has been used on the Opportunity rover, focusing on usage that occurred during a 21 kilometer historic trek to the Mars Endeavour crater.

  15. k-t acceleration in pure phase encode MRI to monitor dynamic flooding processes in rock core plugs.

    Science.gov (United States)

    Xiao, Dan; Balcom, Bruce J

    2014-06-01

    Monitoring the pore system in sedimentary rocks with MRI when fluids are introduced is very important in the study of petroleum reservoirs and enhanced oil recovery. However, the lengthy acquisition time of each image, with pure phase encode MRI, limits the temporal resolution. Spatiotemporal correlations can be exploited to undersample the k-t space data. The stacked frames/profiles can be well approximated by an image matrix with rank deficiency, which can be recovered by nonlinear nuclear norm minimization. Sparsity of the x-t image can also be exploited for nonlinear reconstruction. In this work the results of a low rank matrix completion technique were compared with k-t sparse compressed sensing. These methods are demonstrated with one dimensional SPRITE imaging of a Bentheimer rock core plug and SESPI imaging of a Berea rock core plug, but can be easily extended to higher dimensionality and/or other pure phase encode measurements. These ideas will enable higher dimensionality pure phase encode MRI studies of dynamic flooding processes in low magnetic field systems.

  16. On-Board GPS Clock Monitoring for Signal Integrity

    Science.gov (United States)

    2010-11-01

    Dyke, K. Kovach , J. Kraemer, J. Lavrakas, J. P. Fernow, J. Reese, and N. Attallah, 2003, “GPS Integrity Failure Modes and Effects Analysis,” in...California, USA (Institute of Navigation, Alexandria, Virginia), pp. 689-703. [9] K. Van Dyke, K. Kovach , J. Lavrakas, and B. Carroll, 2004

  17. Autonomous onboard optical processor for driving aid

    Science.gov (United States)

    Attia, Mondher; Servel, Alain; Guibert, Laurent

    1995-01-01

    We take advantage of recent technological advances in the field of ferroelectric liquid crystal silicon back plane optoelectronic devices. These are well suited to perform massively parallel processing tasks. That choice enables the design of low cost vision systems and allows the implementation of an on-board system. We focus on transport applications such as road sign recognition. Preliminary in-car experimental results are presented.

  18. CMOS Camera Array With Onboard Memory

    Science.gov (United States)

    Gat, Nahum

    2009-01-01

    A compact CMOS (complementary metal oxide semiconductor) camera system has been developed with high resolution (1.3 Megapixels), a USB (universal serial bus) 2.0 interface, and an onboard memory. Exposure times, and other operating parameters, are sent from a control PC via the USB port. Data from the camera can be received via the USB port and the interface allows for simple control and data capture through a laptop computer.

  19. MODIS On-board Blackbody Performance

    Science.gov (United States)

    Xiong, Xiaoxiong; Chen, N.; Wu, A.; Wenny, B.; Dodd, J.

    2008-01-01

    Currently, there are two MODIS instruments operated on-orbit: one on-board the Terra spacecraft launched in December 1999 and the other on-board the Aqua spacecraft launched in May 2002. MODIS is a scanning radiometer that has 16 thermal emissive bands (TEBs) in the MWIR and LWIR regions. The remaining spectral bands are in the VISINIR and SWIR regions. The TEBs have a total of 160 detectors (10 detectors per band), which are calibrated on-orbit using an on-board blackbody (BB). MODIS TEB calibration is performed via a quadratic algorithm with its linear calibration coefficients updated on a scan-by-scan basis using each detector's response to the BB. The offset and nonlinear terms of the quadratic calibration equation are stored in a look-up table (LUT). The LUT parameters are derived from pre-launch calibration and updated on-orbit from BB observations, as needed. Typically, the BB is set at a fixed temperature. Periodically, a warm-up and cool-down activity is performed, which enables the BB temperature to be varied from instrument ambient up to 315K. The temperature of the BB is measured each scan using 12 thermistors, which were fully characterized pre-launch with reference to the NIST temperature scale. This paper describes MODIS on-board BB operational activities and performance. The TEB detector response (short-term stability and long-term changes) and noise characterization results derived from BB observations and their impact on the TEB calibration uncertainty are also presented.

  20. Onboard Image Processing System for Hyperspectral Sensor

    Directory of Open Access Journals (Sweden)

    Hiroki Hihara

    2015-09-01

    Full Text Available Onboard image processing systems for a hyperspectral sensor have been developed in order to maximize image data transmission efficiency for large volume and high speed data downlink capacity. Since more than 100 channels are required for hyperspectral sensors on Earth observation satellites, fast and small-footprint lossless image compression capability is essential for reducing the size and weight of a sensor system. A fast lossless image compression algorithm has been developed, and is implemented in the onboard correction circuitry of sensitivity and linearity of Complementary Metal Oxide Semiconductor (CMOS sensors in order to maximize the compression ratio. The employed image compression method is based on Fast, Efficient, Lossless Image compression System (FELICS, which is a hierarchical predictive coding method with resolution scaling. To improve FELICS’s performance of image decorrelation and entropy coding, we apply a two-dimensional interpolation prediction and adaptive Golomb-Rice coding. It supports progressive decompression using resolution scaling while still maintaining superior performance measured as speed and complexity. Coding efficiency and compression speed enlarge the effective capacity of signal transmission channels, which lead to reducing onboard hardware by multiplexing sensor signals into a reduced number of compression circuits. The circuitry is embedded into the data formatter of the sensor system without adding size, weight, power consumption, and fabrication cost.

  1. Onboard Image Processing System for Hyperspectral Sensor.

    Science.gov (United States)

    Hihara, Hiroki; Moritani, Kotaro; Inoue, Masao; Hoshi, Yoshihiro; Iwasaki, Akira; Takada, Jun; Inada, Hitomi; Suzuki, Makoto; Seki, Taeko; Ichikawa, Satoshi; Tanii, Jun

    2015-09-25

    Onboard image processing systems for a hyperspectral sensor have been developed in order to maximize image data transmission efficiency for large volume and high speed data downlink capacity. Since more than 100 channels are required for hyperspectral sensors on Earth observation satellites, fast and small-footprint lossless image compression capability is essential for reducing the size and weight of a sensor system. A fast lossless image compression algorithm has been developed, and is implemented in the onboard correction circuitry of sensitivity and linearity of Complementary Metal Oxide Semiconductor (CMOS) sensors in order to maximize the compression ratio. The employed image compression method is based on Fast, Efficient, Lossless Image compression System (FELICS), which is a hierarchical predictive coding method with resolution scaling. To improve FELICS's performance of image decorrelation and entropy coding, we apply a two-dimensional interpolation prediction and adaptive Golomb-Rice coding. It supports progressive decompression using resolution scaling while still maintaining superior performance measured as speed and complexity. Coding efficiency and compression speed enlarge the effective capacity of signal transmission channels, which lead to reducing onboard hardware by multiplexing sensor signals into a reduced number of compression circuits. The circuitry is embedded into the data formatter of the sensor system without adding size, weight, power consumption, and fabrication cost.

  2. Spacecube: A Family of Reconfigurable Hybrid On-Board Science Data Processors

    Science.gov (United States)

    Flatley, Thomas P.

    2015-01-01

    SpaceCube is a family of Field Programmable Gate Array (FPGA) based on-board science data processing systems developed at the NASA Goddard Space Flight Center (GSFC). The goal of the SpaceCube program is to provide 10x to 100x improvements in on-board computing power while lowering relative power consumption and cost. SpaceCube is based on the Xilinx Virtex family of FPGAs, which include processor, FPGA logic and digital signal processing (DSP) resources. These processing elements are leveraged to produce a hybrid science data processing platform that accelerates the execution of algorithms by distributing computational functions to the most suitable elements. This approach enables the implementation of complex on-board functions that were previously limited to ground based systems, such as on-board product generation, data reduction, calibration, classification, eventfeature detection, data mining and real-time autonomous operations. The system is fully reconfigurable in flight, including data parameters, software and FPGA logic, through either ground commanding or autonomously in response to detected eventsfeatures in the instrument data stream.

  3. Accelerator and radiation physics

    CERN Document Server

    Basu, Samita; Nandy, Maitreyee

    2013-01-01

    "Accelerator and radiation physics" encompasses radiation shielding design and strategies for hadron therapy accelerators, neutron facilities and laser based accelerators. A fascinating article describes detailed transport theory and its application to radiation transport. Detailed information on planning and design of a very high energy proton accelerator can be obtained from the article on radiological safety of J-PARC. Besides safety for proton accelerators, the book provides information on radiological safety issues for electron synchrotron and prevention and preparedness for radiological emergencies. Different methods for neutron dosimetry including LET based monitoring, time of flight spectrometry, track detectors are documented alongwith newly measured experimental data on radiation interaction with dyes, polymers, bones and other materials. Design of deuteron accelerator, shielding in beam line hutches in synchrotron and 14 MeV neutron generator, various radiation detection methods, their characteriza...

  4. Performance characterization of siemens primus linear accelerator under small monitor unit and small segments for the implementation of step-and-shoot intensitymodulated radiotherapy

    Directory of Open Access Journals (Sweden)

    Reena P

    2006-01-01

    Full Text Available Implementation of step-and-shoot intensity-modulated radiotherapy (IMRT needs careful understanding of the accelerator start-up characteristic to ensure accurate and precise delivery of radiation dose to patient. The dosimetric characteristic of a Siemens Primus linear accelerator (LA which delivers 6 and 18 MV x-rays at the dose rate of 300 and 500 monitor unit (MU per minutes (min respectively was studied under the condition of small MU ranging from 1 to 100. Dose monitor linearity was studied at different dose calibration parameter (D1_C0 by measuring ionization at 10 cm depth in a solid water phantom using a 0.6 cc ionization chamber. Monitor unit stability was studied from different intensity modulated (IM groups comprising various combinations of MU per field and number of fields. Stability of beam flatness and symmetry was investigated under normal and IMRT mode for 20x20 cm2 field under small MU using a 2D Profiler kept isocentrically at 5 cm depth. Inter segment response was investigated form 1 to 10 MU by measuring the dose per MU from various IM groups, each consisting of four segments with inter-segment separation of 2 cm. In the range 1-4 MU, the dose linearity error was more than 5% (max -32% at 1 MU for 6 MV x-rays at factory calibrated D1_C0 value of 6000. The dose linearity error was reduced to -10.95% at 1 MU, within -3% for 2 and 3 MU and ±1% for MU ≥4 when the D1_C0 was subsequently tuned at 4500. For 18 MV x-rays, the dose linearity error at factory calibrated D1_C0 value of 4400 was within ±1% for MU ≥ 3 with maximum of -13.5 observed at 1 MU. For both the beam energies and MU/field ≥ 4, the stability of monitor unit tested for different IM groups was within ±1% of the dose from the normal treatment field. This variation increases to -2.6% for 6 MV and -2.7% for 18 MV x-rays for 2 MU/field. No significant variation was observed in the stability of beam profile measured from normal and IMRT mode. The beam flatness

  5. Minimized Bolus-Type Wireless Sensor Node with a Built-In Three-Axis Acceleration Meter for Monitoring a Cow's Rumen Conditions.

    Science.gov (United States)

    Nogami, Hirofumi; Arai, Shozo; Okada, Hironao; Zhan, Lan; Itoh, Toshihiro

    2017-03-27

    Monitoring rumen conditions in cows is important because a dysfunctional rumen system may cause death. Sub-acute ruminal acidosis (SARA) is a typical disease in cows, and is characterized by repeated periods of low ruminal pH. SARA is regarded as a trigger for rumen atony, rumenitis, and abomasal displacement, which may cause death. In previous studies, rumen conditions were evaluated by wireless sensor nodes with pH measurement capability. The primary advantage of the pH sensor is its ability to continuously measure ruminal pH. However, these sensor nodes have short lifetimes since they are limited by the finite volume of the internal liquid of the reference electrode. Mimicking rumen atony, we attempt to evaluate the rumen condition using wireless sensor nodes with three-axis accelerometers. The theoretical life span of such sensor nodes depends mainly on the transmission frequency of acceleration data and the size of the battery, and the proposed sensor nodes are 30.0 mm in diameter and 70.0 mm in length and have a life span of over 600 days. Using the sensor nodes, we compare the rumen motility of the force transducer measurement with the three-axis accelerometer data. As a result, we can detect discriminative movement of rumen atony.

  6. Measurement of the dosimetric parameters for low monitor units in step-and-shoot IMRT delivered by Siemens Artiste linear accelerators; Medida de los parametros dosimetricos para bajo numero de unidades monitor en IMRT segmentada estatica administrada por aceleradores lineales Siemens Artiste

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Rodriguez, C.; Lopez Fernandez, A.; Saez Beltran, M.; Martin Martin, G.; Alonso Iracheta, L.

    2012-07-01

    Absorbed dose linearity and beam stability, both for low monitor units, are important factors for ensuring planned dose delivery in step-and-shoot IMRT. For Siemens Artiste linear accelerators, under IMRT stable irradiation conditions and for a single segment of 20 cm x 20 cm field size, the linearity of the absorbed dose with the monitor units, field flatness and symmetry have been measured for the range between 1 and 10 monitor units. We have found that absorbed dose linearity with monitor units is within 2% down to 2 monitor units and it is about 9% for 1 monitor unit. Flatness and symmetry values show variations within 1% down to 2 monitor units and increase by 9% for lower values. Using our monitor unit distribution per segment in IMRT we estimate that the uncertainty in absorbed dose for a whole treatment due to these factors is less than 1% (k= 3). (Author) 13 refs.

  7. Monitoring for volcano-hydrothermal activity using continuous gravity and local ground acceleration measurements: New deployments at Inferno Crater, Waimangu and White Island, New Zealand

    Science.gov (United States)

    Jolly, Arthur; Fournier, Nico; Cole-Baker, Jeremy; Miller, Craig

    2010-05-01

    Volcanoes with crater lakes are often characterised by shallow hydrothermal systems which display cyclic behaviour (temperature, lake level, chemistry, etc.) and shallow seismic tremor. Present monitoring programmes in New Zealand include routine collection of these observables, but the associated shallow sub-surface processes are still inadequately modelled and poorly understood. Models would be better constrained with the incorporation of additional geophysical parameters. To this end, we have established a new test programme to continuously monitor for micro-gravity variations at New Zealand volcanoes. We utilise a Micro-g-LaCoste gPhone relative gravity meter having 1 Hz sample rate and a measurement precision of 1 microgal to test the viability of gravity monitoring for volcano-hydrothermal systems. We have initially tested the new sensor in a short term deployment (~2 months) at Inferno Crater, Waimangu, New Zealand. Inferno shows dramatic variations in crater lake level (> 7 m range), temperature (>40o C range) and hydrothermally derived tremor, all over a period of ~5 weeks. The amplitude and period of these observables are ideal for testing gravity variations associated with a cycling hydrothermal system because several cycles can be obtained in a relatively short campaign. We have deployed the gravity sensor into a buried vault having a stable concrete base to minimise local environmental influences. This vault is located ~20 meters from Inferno Lake edge (at high stand) and offers sufficient noise reduction to measure the gravitational effects associated with lake level changes. We will show results for the new gravity meter including raw relative gravity measurements and first order corrections (earth-tide, ocean loading, sensor level, temperature, and barometric pressure) to obtain both residual gravity and overprinted local ground accelerations (earthquakes and local tremor). To examine the effects of local ground vibrations on the gravity meter, we

  8. Onboard pattern recognition for autonomous UAV landing

    Science.gov (United States)

    Sung, Chen-Ko; Segor, Florian

    2012-10-01

    The civil security and supervision system AMFIS was developed at the Fraunhofer IOSB as a mobile support system using multiple UAVs for rescue forces in accidents or disasters. To gain a higher level of autonomy for these UAVs, different onboard process chains of image exploitation for tracking landmarks and of control technologies for UAV navigation were implemented and examined to achieve a redundant and reliable UAV precision landing. First experiments have allowed to validate the process chains and to develop a demonstration system for the tracking of landmarks in order to prevent and to minimize any confusion on landing.

  9. On-board demux/demod

    Science.gov (United States)

    Sayegh, S.; Kappes, M.; Thomas, J.; Snyder, J.; Eng, M.; Poklemba, John J.; Steber, M.; House, G.

    1991-01-01

    To make satellite channels cost competitive with optical cables, the use of small, inexpensive earth stations with reduced antenna size and high powered amplifier (HPA) power will be needed. This will necessitate the use of high e.i.r.p. and gain-to-noise temperature ratio (G/T) multibeam satellites. For a multibeam satellite, onboard switching is required in order to maintain the needed connectivity between beams. This switching function can be realized by either an receive frequency (RF) or a baseband unit. The baseband switching approach has the additional advantage of decoupling the up-link and down-link, thus enabling rate and format conversion as well as improving the link performance. A baseband switching satellite requires the demultiplexing and demodulation of the up-link carriers before they can be switched to their assigned down-link beams. Principles of operation, design and implementation issues of such an onboard demultiplexer/demodulator (bulk demodulator) that was recently built at COMSAT Labs. are discussed.

  10. Standardization activity for the spacecraft onboard interfaces

    Science.gov (United States)

    Smith, J. F.; Plummer, C.; Plancke, P.

    2003-01-01

    The Consultative Committee for Space Data Systems (CCSDS) is an international organization of national space agencies that is organized to promote theinterchange of space related information. CCSDS is branching out to provide new standards to enhanced reuse of spacecraft equipment and software onboard of a spacecraft. This effort is know as Spacecraft Onboard Interface (SOIF). SOIF expects that these standards will be well used within the space community, and that they will be based on the well-known Internet protocols. This paper will provide a description of the SOIF work by reviewing this work with three orthogonal views. The Services View describes the data communications services that are provided to the users. The Interoperability view provides a description to users on how to use SOIF to interchange between different spacecraft data busses. And finally, the Protocol view, describes the protocols and services that are to be implemented in order to provide the users with the advantages of the SOIF architecture. This paper will give the reader an excellent introduction to the work of the international SOIF team.

  11. Science Benefits of Onboard Spacecraft Navigation

    Science.gov (United States)

    Cangahuala, Al; Bhaskaran, Shyam; Owen, Bill

    2012-01-01

    Primitive bodies (asteroids and comets), which have remained relatively unaltered since their formation, are important targets for scientific missions that seek to understand the evolution of the solar system. Often the first step is to fly by these bodies with robotic spacecraft. The key to maximizing data returns from these flybys is to determine the spacecraft trajectory relative to the target body-in short, navigate the spacecraft- with sufficient accuracy so that the target is guaranteed to be in the instruments' field of view. The most powerful navigation data in these scenarios are images taken by the spacecraft of the target against a known star field (onboard astrometry). Traditionally, the relative trajectory of the spacecraft must be estimated hours to days in advance using images collected by the spacecraft. This is because of (1)!the long round-trip light times between the spacecraft and the Earth and (2)!the time needed to downlink and process navigation data on the ground, make decisions based on the result, and build and uplink instrument pointing sequences from the results. The light time and processing time compromise navigation accuracy considerably, because there is not enough time to use more accurate data collected closer to the target-such data are more accurate because the angular capability of the onboard astrometry is essentially constant as the distance to the target decreases, resulting in better "plane-of- sky" knowledge of the target. Excellent examples of these timing limitations are high-speed comet encounters. Comets are difficult to observe up close; their orbits often limit scientists to brief, rapid flybys, and their coma further restricts viewers from seeing the nucleus in any detail, unless they can view the nucleus at close range. Comet nuclei details are typically discernable for much shorter durations than the roundtrip light time to Earth, so robotic spacecraft must be able to perform onboard navigation. This onboard

  12. Analysis of Noise Exposure Measurements Acquired Onboard the International Space Station

    Science.gov (United States)

    Limardo, Jose G.; Allen, Christopher S.

    2011-01-01

    The International Space Station (ISS) is a unique workplace environment for U.S. astronauts and Russian cosmonauts to conduct research and live for a period of six months or more. Noise has been an enduring environmental physical hazard that has been a challenge for the U.S. space program since before the Apollo era. Noise exposure in ISS poses significant risks to the crewmembers, such as; hearing loss (temporary or permanent), possible disruptions of crew sleep, interference with speech intelligibility and communication, possible interference with crew task performance, and possible reduction in alarm audibility. Acoustic measurements were made onboard ISS and compared to requirements in order to assess the acoustic environment to which the crewmembers are exposed. The purpose of this paper is to describe in detail the noise exposure monitoring program as well as an assessment of the acoustic dosimeter data collected to date. The hardware currently being used for monitoring the noise exposure onboard ISS will be discussed. Acoustic data onboard ISS has been collected since the beginning of ISS (Increment 1, November 2001). Noise exposure data analysis will include acoustic dosimetry logged data from crew-worn dosimeters during work and sleep periods and also fixed-location measurements from Increment 1 to present day. Noise exposure levels (8-, 16- and 24-hr), LEQ, will also be provided and discussed in this paper. Future directions and recommendations for the noise exposure monitoring program will be highlighted. This acoustic data is used to ensure a safe and healthy working and living environment for the crewmembers onboard the ISS.

  13. Future accelerators (?)

    Energy Technology Data Exchange (ETDEWEB)

    John Womersley

    2003-08-21

    I describe the future accelerator facilities that are currently foreseen for electroweak scale physics, neutrino physics, and nuclear structure. I will explore the physics justification for these machines, and suggest how the case for future accelerators can be made.

  14. Onboard Image Registration from Invariant Features

    Science.gov (United States)

    Wang, Yi; Ng, Justin; Garay, Michael J.; Burl, Michael C

    2008-01-01

    This paper describes a feature-based image registration technique that is potentially well-suited for onboard deployment. The overall goal is to provide a fast, robust method for dynamically combining observations from multiple platforms into sensors webs that respond quickly to short-lived events and provide rich observations of objects that evolve in space and time. The approach, which has enjoyed considerable success in mainstream computer vision applications, uses invariant SIFT descriptors extracted at image interest points together with the RANSAC algorithm to robustly estimate transformation parameters that relate one image to another. Experimental results for two satellite image registration tasks are presented: (1) automatic registration of images from the MODIS instrument on Terra to the MODIS instrument on Aqua and (2) automatic stabilization of a multi-day sequence of GOES-West images collected during the October 2007 Southern California wildfires.

  15. Worry and its correlates onboard cruise ships.

    Science.gov (United States)

    Wolff, Katharina; Larsen, Svein; Marnburg, Einar; Øgaard, Torvald

    2013-01-01

    The present study examined job-specific worry, as well as possible predictors of such worry, namely job-specific self-efficacy and supervisor dispositionism. 133 non-supervising crew members at different departments onboard upmarket cruise ships filled in a questionnaire during one of their journeys. Findings show that employees report moderate amounts of job-specific worry and the galley crew reports significantly greater amounts of worry than the other departments. Results also indicate that cruise ship crews worry somewhat more than workers in the land based service sector. Furthermore it was found that supervisor dispositionism, i.e. supervisors with fixed mindsets, was related to greater amounts of worry among the crew. Surprisingly, job-specific self-efficacy was unrelated to job-specific worry.

  16. Fusion of Onboard Sensors for Better Navigation

    Directory of Open Access Journals (Sweden)

    Ravi Shankar

    2013-03-01

    Full Text Available This paper presents simulation results of navigation sensors such as integrated navigation system (INS, global navigation satellite system (GNSS and TACAN sensors onboard an aircraft to find the navigation solutions. Mathematical models for INS, GNSS (GPS satellite trajectories, GPS receiver and TACAN characteristics are simulated in Matlab. The INS simulation generates the output for position, velocity and attitude based on aerosond dynamic model. The GPS constellation is generated based on the YUMA almanac data. The GPS dilution of precession (DOP parameters are calculated and the best combination of four satellites (minimum PDOP is used for calculating the user position and velocity. The INS, GNSS, and TACAN solutions are integrated through loosely coupled extended Kalman filter for calculating the optimum navigation solution. The work is starting stone for providing aircraft based augmentation system for required navigation performance in terms of availability, accuracy, continuity and integrity.

  17. 40 CFR 86.005-17 - On-board diagnostics.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false On-board diagnostics. 86.005-17... Petroleum Gas-Fueled and Methanol-Fueled Heavy-Duty Vehicles § 86.005-17 On-board diagnostics. (a) General... “Road Vehicles-Diagnostics on Controller Area Network (CAN)—Part 4: Requirements for...

  18. Onboard Prediction of Propagation Loss in Shallow Water

    Science.gov (United States)

    1981-09-16

    substrate roughn*p, (4) modal coupling, and (6) biologia scAtterers;,6. Grain asiz distribution Is not an adequate predctor of acoustical properties; heuce...INTRODUCTION ......................................... 1 GENERAL COMMENTS ................................... 2 SEDIMENT SOUND SPEED AND DENSITY...for an onboard perfor- mance prediction capability in shallow water. There is a general requirement for an onboard performance prediction capability

  19. On-board processing of video image sequences

    DEFF Research Database (Denmark)

    Andersen, Jakob Dahl; Chanrion, Olivier Arnaud; Forchhammer, Søren

    2008-01-01

    of the mission is to study transient luminous events (TLE) above severe thunderstorms: the sprites, jets and elves. Other atmospheric phenomena are also studied including aurora, gravity waves and meteors. As part of the ASIM Phase B study, on-board processing of data from the cameras is being developed...... and evaluated. On-board there are six video cameras each capturing images of 1024times1024 pixels of 12 bpp at a frame rate of 15 fps, thus totalling 1080 Mbits/s. In comparison the average downlink data rate for these images is projected to be 50 kbit/s. This calls for efficient on-board processing to select...... and compress the data. Algorithms for on-board processing of the image data are presented as well as evaluation of the performance. The main processing steps are event detection, image cropping and image compression. The on-board processing requirements are also evaluated....

  20. Real-Time Onboard Global Nonlinear Aerodynamic Modeling from Flight Data

    Science.gov (United States)

    Brandon, Jay M.; Morelli, Eugene A.

    2014-01-01

    Flight test and modeling techniques were developed to accurately identify global nonlinear aerodynamic models onboard an aircraft. The techniques were developed and demonstrated during piloted flight testing of an Aermacchi MB-326M Impala jet aircraft. Advanced piloting techniques and nonlinear modeling techniques based on fuzzy logic and multivariate orthogonal function methods were implemented with efficient onboard calculations and flight operations to achieve real-time maneuver monitoring and analysis, and near-real-time global nonlinear aerodynamic modeling and prediction validation testing in flight. Results demonstrated that global nonlinear aerodynamic models for a large portion of the flight envelope were identified rapidly and accurately using piloted flight test maneuvers during a single flight, with the final identified and validated models available before the aircraft landed.

  1. Design of the magnetic diagnostics unit onboard LISA Pathfinder

    CERN Document Server

    Diaz-Aguiló, Marc; Ramos-Castro, Juan; Lobo, Alberto; García-Berro, Enrique

    2012-01-01

    LISA (Laser Interferometer Space Antenna) is a joint mission of ESA and NASA which aims to be the first space-borne gravita- tional wave observatory. Due to the high complexity and technological challenges that LISA will face, ESA decided to launch a technological demonstrator, LISA Pathfinder. The payload of LISA Pathfinder is the so-called LISA Technology Package, and will be the highest sensitivity geodesic explorer flown to date. The LISA Technology Package is designed to measure relative accelerations between two test masses in nominal free fall (geodesic motion). The magnetic, thermal and radiation disturbances affecting the payload are monitored and dealt by the diagnostics subsystem. The diagnostics subsystem consists of several modules, and one of these is the magnetic diagnostics unit. Its main function is the assessment of differential acceleration noise between test masses due to the magnetic effects. To do so, it has to determine the magnetic characteristics of the test masses, namely their magne...

  2. Accelerating Value Creation with Accelerators

    DEFF Research Database (Denmark)

    Jonsson, Eythor Ivar

    2015-01-01

    accelerator programs. Microsoft runs accelerators in seven different countries. Accelerators have grown out of the infancy stage and are now an accepted approach to develop new ventures based on cutting-edge technology like the internet of things, mobile technology, big data and virtual reality. It is also...... with the traditional audit and legal universes and industries are examples of emerging potentials both from a research and business point of view to exploit and explore further. The accelerator approach may therefore be an Idea Watch to consider, no matter which industry you are in, because in essence accelerators...

  3. On-board aircrew dosimetry using a semiconductor spectrometer

    CERN Document Server

    Spurny, F

    2002-01-01

    Radiation fields on board aircraft contain particles with energies up to a few hundred MeV. Many instruments have been tested to characterise these fields. This paper presents the results of studies on the use of an Si diode spectrometer to characterise these fields. The spectrometer has been in use since spring 2000 on more than 130 return flights to monitor and characterise the on-board field. During a Czech Airlines flight from Prague to New York it was possible to register the effects of an intense solar flare, (ground level event, GLE 60), which occurred on 15 April 2001. It was found that the number of deposition events registered was increased by about 70% and the dose in Si by a factor of 2.0 when compared with the presence of galactic cosmic rays alone. Directly measured data are interpreted with respect to on-earth reference field calibration (photons, CERN high-energy particles); it was found that this approach leads to encouraging results and should be followed up. (7 refs).

  4. Autonomous Onboard Science Data Analysis for Comet Missions

    Science.gov (United States)

    Thompson, David R.; Tran, Daniel Q.; McLaren, David; Chien, Steve A.; Bergman, Larry; Castano, Rebecca; Doyle, Richard; Estlin, Tara; Lenda, Matthew

    2012-01-01

    Coming years will bring several comet rendezvous missions. The Rosetta spacecraft arrives at Comet 67P/Churyumov-Gerasimenko in 2014. Subsequent rendezvous might include a mission such as the proposed Comet Hopper with multiple surface landings, as well as Comet Nucleus Sample Return (CNSR) and Coma Rendezvous and Sample Return (CRSR). These encounters will begin to shed light on a population that, despite several previous flybys, remains mysterious and poorly understood. Scientists still have little direct knowledge of interactions between the nucleus and coma, their variation across different comets or their evolution over time. Activity may change on short timescales so it is challenging to characterize with scripted data acquisition. Here we investigate automatic onboard image analysis that could act faster than round-trip light time to capture unexpected outbursts and plume activity. We describe one edge-based method for detect comet nuclei and plumes, and test the approach on an existing catalog of comet images. Finally, we quantify benefits to specific measurement objectives by simulating a basic plume monitoring campaign.

  5. Onboard Plasmatron Hydrogen Production for Improved Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Daniel R. Cohn; Leslie Bromberg; Kamal Hadidi

    2005-12-31

    A plasmatron fuel reformer has been developed for onboard hydrogen generation for vehicular applications. These applications include hydrogen addition to spark-ignition internal combustion engines, NOx trap and diesel particulate filter (DPF) regeneration, and emissions reduction from spark ignition internal combustion engines First, a thermal plasmatron fuel reformer was developed. This plasmatron used an electric arc with relatively high power to reform fuels such as gasoline, diesel and biofuels at an oxygen to carbon ratio close to 1. The draw back of this device was that it has a high electric consumption and limited electrode lifetime due to the high temperature electric arc. A second generation plasmatron fuel reformer was developed. It used a low-current high-voltage electric discharge with a completely new electrode continuation. This design uses two cylindrical electrodes with a rotating discharge that produced low temperature volumetric cold plasma., The lifetime of the electrodes was no longer an issue and the device was tested on several fuels such as gasoline, diesel, and biofuels at different flow rates and different oxygen to carbon ratios. Hydrogen concentration and yields were measured for both the thermal and non-thermal plasmatron reformers for homogeneous (non-catalytic) and catalytic reforming of several fuels. The technology was licensed to an industrial auto part supplier (ArvinMeritor) and is being implemented for some of the applications listed above. The Plasmatron reformer has been successfully tested on a bus for NOx trap regeneration. The successful development of the plasmatron reformer and its implementation in commercial applications including transportation will bring several benefits to the nation. These benefits include the reduction of NOx emissions, improving engine efficiency and reducing the nation's oil consumption. The objective of this program has been to develop attractive applications of plasmatron fuel reformer

  6. Memory-Efficient Onboard Rock Segmentation

    Science.gov (United States)

    Burl, Michael C.; Thompson, David R.; Bornstein, Benjamin J.; deGranville, Charles K.

    2013-01-01

    Rockster-MER is an autonomous perception capability that was uploaded to the Mars Exploration Rover Opportunity in December 2009. This software provides the vision front end for a larger software system known as AEGIS (Autonomous Exploration for Gathering Increased Science), which was recently named 2011 NASA Software of the Year. As the first step in AEGIS, Rockster-MER analyzes an image captured by the rover, and detects and automatically identifies the boundary contours of rocks and regions of outcrop present in the scene. This initial segmentation step reduces the data volume from millions of pixels into hundreds (or fewer) of rock contours. Subsequent stages of AEGIS then prioritize the best rocks according to scientist- defined preferences and take high-resolution, follow-up observations. Rockster-MER has performed robustly from the outset on the Mars surface under challenging conditions. Rockster-MER is a specially adapted, embedded version of the original Rockster algorithm ("Rock Segmentation Through Edge Regrouping," (NPO- 44417) Software Tech Briefs, September 2008, p. 25). Although the new version performs the same basic task as the original code, the software has been (1) significantly upgraded to overcome the severe onboard re source limitations (CPU, memory, power, time) and (2) "bulletproofed" through code reviews and extensive testing and profiling to avoid the occurrence of faults. Because of the limited computational power of the RAD6000 flight processor on Opportunity (roughly two orders of magnitude slower than a modern workstation), the algorithm was heavily tuned to improve its speed. Several functional elements of the original algorithm were removed as a result of an extensive cost/benefit analysis conducted on a large set of archived rover images. The algorithm was also required to operate below a stringent 4MB high-water memory ceiling; hence, numerous tricks and strategies were introduced to reduce the memory footprint. Local filtering

  7. Accelerating Value Creation with Accelerators

    DEFF Research Database (Denmark)

    Jonsson, Eythor Ivar

    2015-01-01

    Accelerators can help to accelerate value creation. Accelerators are short-term programs that have the objective of creating innovative and fast growing ventures. They have gained attraction as larger corporations like Microsoft, Barclays bank and Nordea bank have initiated and sponsored accelera......Accelerators can help to accelerate value creation. Accelerators are short-term programs that have the objective of creating innovative and fast growing ventures. They have gained attraction as larger corporations like Microsoft, Barclays bank and Nordea bank have initiated and sponsored...... an approach to facilitate implementation and realization of business ideas and is a lucrative approach to transform research into ventures and to revitalize regions and industries in transition. Investors have noticed that the accelerator approach is a way to increase the possibility of success by funnelling...

  8. Fast and Adaptive Lossless Onboard Hyperspectral Data Compression System

    Science.gov (United States)

    Aranki, Nazeeh I.; Keymeulen, Didier; Kimesh, Matthew A.

    2012-01-01

    Modern hyperspectral imaging systems are able to acquire far more data than can be downlinked from a spacecraft. Onboard data compression helps to alleviate this problem, but requires a system capable of power efficiency and high throughput. Software solutions have limited throughput performance and are power-hungry. Dedicated hardware solutions can provide both high throughput and power efficiency, while taking the load off of the main processor. Thus a hardware compression system was developed. The implementation uses a field-programmable gate array (FPGA). The implementation is based on the fast lossless (FL) compression algorithm reported in Fast Lossless Compression of Multispectral-Image Data (NPO-42517), NASA Tech Briefs, Vol. 30, No. 8 (August 2006), page 26, which achieves excellent compression performance and has low complexity. This algorithm performs predictive compression using an adaptive filtering method, and uses adaptive Golomb coding. The implementation also packetizes the coded data. The FL algorithm is well suited for implementation in hardware. In the FPGA implementation, one sample is compressed every clock cycle, which makes for a fast and practical realtime solution for space applications. Benefits of this implementation are: 1) The underlying algorithm achieves a combination of low complexity and compression effectiveness that exceeds that of techniques currently in use. 2) The algorithm requires no training data or other specific information about the nature of the spectral bands for a fixed instrument dynamic range. 3) Hardware acceleration provides a throughput improvement of 10 to 100 times vs. the software implementation. A prototype of the compressor is available in software, but it runs at a speed that does not meet spacecraft requirements. The hardware implementation targets the Xilinx Virtex IV FPGAs, and makes the use of this compressor practical for Earth satellites as well as beyond-Earth missions with hyperspectral instruments.

  9. Fusion of Onboard Sensors for Better Navigation

    Directory of Open Access Journals (Sweden)

    Ravi Shankar

    2013-03-01

    Full Text Available This paper presents simulation results of navigation sensors such as integrated navigation system (INS, global navigation satellite system (GNSS and TACAN sensors onboard an aircraft to find the navigation solutions. Mathematical models for INS, GNSS (GPS satellite trajectories, GPS receiver and TACAN characteristics are simulated in Matlab. The INS simulation generates the output for position, velocity and attitude based on aerosond dynamic model. The GPS constellation is generated based on the YUMA almanac data. The GPS dilution of precession (DOP parameters are calculated and the best combination of four satellites (minimum PDOP is used for calculating the user position and velocity. The INS, GNSS, and TACAN solutions are integrated through loosely coupled extended Kalman filter for calculating the optimum navigation solution. The work is starting stone for providing aircraft based augmentation system for required navigation performance in terms of availability, accuracy, continuity and integrity.Defence Science Journal, 2013, 63(2, pp.145-152, DOI:http://dx.doi.org/10.14429/dsj.63.4256

  10. The Perseus-Exobiology experiment onboard MIR

    Science.gov (United States)

    Barbier, B.; Boillot, F.; Chabin, A.; Buré, C.; Venet, M.; Belsky, A.; Jacquet, R.; Bertrand-Urbaniak, M.; Delmas, A.; Brack, A.

    2002-11-01

    Two amino acids, L-leucine and "α-methyl-L-leucine; a cyclic dipeptide, L-leucine-diketopiperazine, and an activated tripeptide L-trileucine thioethylester, were exposed for three months to space conditions onboard the MIR station during the Perseus-Exobiology mission in 1999. These samples were exposed in order to study the exogeneous hypothesis for the origin of some of the important biological building blocks of life. The four compounds were exposed both free and associated with basalt, clay and meteorite powder to simulate the effects of potential meteorite protection. Post-flight analyses did not reveal any racemization or polymerisation of the exposed compounds. Approximately half of the amino acids were photolyzed with decarboxylation apparently the primary cause. Peptides were less sensitive to photolysis which mainly occurred by decarbonylation, but were partly lost by natural degradation or sublimation. The best mineral protection for the samples was ensured by the meteorite powder, which exhibits the highest absorption in VUV, whereas clay, almost transparent in VUV was the least efficient. By varying the thickness of the meteorite layer, it was determined that a 5 μm film was necessary to ensure efficient protection against UV radiation.

  11. Reconstruction of the HYSHOT2 Flight from Onboard Sensors

    Science.gov (United States)

    Owen, R.; Cain, T.

    2005-02-01

    The scramjet flight test, Hyshot 2, flew on the 30 July 2002. The programme, led by the University of Queensland, had the primary objective of obtaining supersonic combustion data in flight for comparison with measurements made in a shock tunnel. QinetiQ was one of the project sponsors, and also provided aerodynamic data and trajectory predictions for the ballistic re-entry of the spinning sounding rocket. This paper presents the reconstruction of the Hyshot2 trajectory from onboard measurements with accelerometers, pressure transducers, a magnetometer and a horizon sensor. LIST OF SYMBOLS a orbit semi major axis, m av acceleration along the velocity vector, m.s-2 ay acceleration along the body y axis b orbit semi minor axis, m e orbit eccentricity f ratio of drag to axial force g local gravity, m.s-2 h length of Earth tangent, m kyy radius of gyration, 123cm m UQ-Orion mass, 239kg p vehicle spin pN Nitrogen tank pressure, kPa r distance from the centre of the Earth, m t time from ignition s u horizontal velocity, m.s-1 xa distance from the centre of gravity to the accelerometer, 131cm xF distance from the centre of gravity to the cold gas thruster, 194cm Ath cold gas nozzle throat area, 14.5mm2 B magnetic flux in global coordinates, Gauss CF Thrust Coefficient H angular momentum vector Ixx Roll inertia Iyy Pitch inertia, 361kgm2 M Mach number Pa fuelled intake pressure Pb unfuelled intake pressure Pt pitot pressure, kPa Re radius of the Earth, km T horizon sensor period, s V velocity along the flight path, m.s-1 x, y, z body axes, m X, Y, Z global axes, m latitude, rad longitude, rad flight path angle, rad angle of the horizon sensor sight from the vehicle, rad Pitch, rad angle between the centre of the Earth, the horizon sensor and the horizon, rad angle around the great circle, rad density, kg/m3 angle of attack, rad horizon sensor pulse duration, s Roll angle, rad half the roll angle through which reflected light from the Earth is sensed, rad angle of

  12. The New Fault Tolerant Onboard Computer for Microsatellite Missions

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper describes an onboard computer with dual processing modules. Each processing module is composed of 32 bit ARM reduced instruction set computer processor and other commercial-off-the-shelf devices. A set of fault handling mechanisms is implemented in the computer system, which enables the system to tolerate a single fault. The onboard software is organized around a set of processes that communicate among each other through a routing process. Meeting an extremely tight set of constraints that include mass, volume, power consumption and space environmental conditions, the fault-tolerant onboard computer has excellent data processing capability that can meet the erquirements of micro-satellite missions.

  13. RECIRCULATING ACCELERATION

    Energy Technology Data Exchange (ETDEWEB)

    BERG,J.S.; GARREN,A.A.; JOHNSTONE,C.

    2000-04-07

    This paper compares various types of recirculating accelerators, outlining the advantages and disadvantages of various approaches. The accelerators are characterized according to the types of arcs they use: whether there is a single arc for the entire recirculator or there are multiple arcs, and whether the arc(s) are isochronous or non-isochronous.

  14. LIBO accelerates

    CERN Multimedia

    2002-01-01

    The prototype module of LIBO, a linear accelerator project designed for cancer therapy, has passed its first proton-beam acceleration test. In parallel a new version - LIBO-30 - is being developed, which promises to open up even more interesting avenues.

  15. Accelerating Inspire

    CERN Document Server

    AUTHOR|(CDS)2266999

    2017-01-01

    CERN has been involved in the dissemination of scientific results since its early days and has continuously updated the distribution channels. Currently, Inspire hosts catalogues of articles, authors, institutions, conferences, jobs, experiments, journals and more. Successful orientation among this amount of data requires comprehensive linking between the content. Inspire has lacked a system for linking experiments and articles together based on which accelerator they were conducted at. The purpose of this project has been to create such a system. Records for 156 accelerators were created and all 2913 experiments on Inspire were given corresponding MARC tags. Records of 18404 accelerator physics related bibliographic entries were also tagged with corresponding accelerator tags. Finally, as a part of the endeavour to broaden CERN's presence on Wikipedia, existing Wikipedia articles of accelerators were updated with short descriptions and links to Inspire. In total, 86 Wikipedia articles were updated. This repo...

  16. Analysis of thickness measurements on secondary lines in EDF PWRs to evaluate the accuracy of the flow accelerated corrosion monitoring software: BRT-CICERO

    Energy Technology Data Exchange (ETDEWEB)

    Persoz, Matthieu [CAP AMPERE, 1 place Pleyel, 93282 Saint Denis (France); Bouvier, Jean-Baptiste [CNEN, 165-173 av. Pierre Brossolette, 92542 Montrouge Cedex (France); Ardillon, Emmanuel [R and D Division, EDF, 6 quai Watier, 78401 Chatou Cedex (France); Trevin, Stephane [SEPTEN, 12 - 14 av. Dutrievoz, 69628 Villeurbanne Cedex (France)

    2006-09-15

    The surveillance of Flow Accelerated Corrosion (FAC) on secondary pipes is a major concern for every nuclear power plant operator. After the Surry accident in 1986, EDF launched a computer code development program to monitor this degradation phenomenon. A chemical corrosion model has been developed, based on laboratory test results obtained by EDF R and D since the late 70's. This model enables to compute the wall thickness loss of pipes submitted to FAC, with respect to the thermo-hydraulic conditions, the fluid chemistry, the material chromium content, the pipe geometry and the cycles duration. The computer code, called BRT-CICERO(TM), has first been tested on a few plants in the years 1993-1995. Most of the EDF NPPs began to use it afterwards. In 2001, after the discovery of a severe damage on a 4'' x 6'' reducer at Fessenheim unit 2, that was correctly predicted by BRT-CICERO(TM), the EDF corporate level made its use mandatory for each of its 58 Pressurized Water Reactors (PWR). Several years of operation and experience feedback have enabled to carry out different improvements on the BRT-CICERO(TM) software. Since 2003, EDF NPPs are using the 2.2 version. At the beginning of year 2005, the 58 BRT-CICERO(TM) input-databases were gathered and structured in a form such that statistical treatments could be made. A very great number of data were collected from BRT-CICERO(TM) input-databases by a specific modification of a tool integrated into the software. It appears that a statistical approach could allow an effective analysis of these data. The first goal of this study was to give the degree of confidence in the application and this approach appeared effective. The second goal was to prove that a part of the conservatism is due to the FAC kinetics calculation algorithm implemented in BRT-CICERO(TM). The investigation of the relative difference between measured and calculated thicknesses shows that a part of the conservatism should be due

  17. The ECLAIRs telescope onboard the SVOM mission for gamma-ray burst studies

    CERN Document Server

    Schanne, Stephane

    2008-01-01

    The X- and gamma-ray telescope ECLAIRs onboard the future mission for gamma-ray burst studies SVOM (Space-based multi-band astronomical Variable Objects Monitor) is foreseen to operate in orbit from 2013 on. ECLAIRs will provide fast and accurate GRB triggers to other onboard telescopes, as well as to the whole GRB community, in particular ground-based follow-up telescopes. With its very low energy threshold ECLAIRs is particularly well suited for the detection of highly redshifted GRB. The ECLAIRs X- and gamma-ray imaging camera (CXG), used for GRB detection and localization, is combined with a soft X-ray telescope (SXT) for afterglow observations and position refinement. The CXG is a 2D-coded mask imager with a 1024 cm$^2$ detection plane made of 80$\\times$80 CdTe pixels, sensitive from 4 to 300 keV, with imaging capabilities up to about 120 keV and a localization accuracy better than 10 arcmin. The CXG permanently observes a 2 sr-wide field of the sky and provides photon data to the onboard science and tri...

  18. Evaluation of area monitor response for neutrons in radiation field generated by a 15 MV clinic accelerator; Avaliacao da resposta dos monitores de area para neutrons em campo de radiacao gerado por um acelerador clinico de 15 MV

    Energy Technology Data Exchange (ETDEWEB)

    Salgado, Ana Paula

    2011-07-01

    The clinical importance and usage of linear accelerators in cancer treatment increased significantly in the last years. Coupled with this growth came the concern about the use of accelerators with energies over to 10 MeV which produce therapeutic beam contaminated with neutrons generated when high-energy photons interact with high-atomic-number materials such as tungsten and lead present in the accelerator itself. At these facilities, measurements of the ambient dose equivalent for neutrons present difficulties owing to the existence of a mixed radiation field and possible electromagnetic interference near the accelerator. The Neutron Laboratory of the IRD - Brazilian Institute for Radioprotection and Dosimetry, aiming to evaluate the survey meters performance at these facilities, initiated studies of instrumentation response in the presence of different neutron spectra. Neutrons sources with average energies ranging from 0.55 to 4.2 MeV, four different survey meters and one ionization chamber to obtain the ratio between the dose due to neutrons and gamma radiation were used in this work. The evaluation of these measurements, performed in a 15 MV linear accelerator room is presented. This work presents results that demonstrate the complexity and care needed to make neutrons measurements in radiotherapy treatment rooms containing high energy clinical accelerators. (author)

  19. XMM instrument on-board software maintenance concept

    Science.gov (United States)

    Peccia, N.; Giannini, F.

    1994-01-01

    While the pre-launch responsibility for the production, validation and maintenance of instrument on-board software traditionally lies with the experimenter, the post-launch maintenance has been the subject of ad hoc arrangements with the responsibility shared to different extent between the experimenter, ESTEC and ESOC. This paper summarizes the overall design and development of the instruments on-board software for the XMM satellite, and describes the concept adopted for the maintenance of such software post-launch. The paper will also outline the on-board software maintenance and validation facilities and the expected advantages to be gained by the proposed strategy. Conclusions with respect to adequacy of this approach will be presented as well as recommendations for future instrument on-board software developments.

  20. Design of Onboard Instrument Based on Virtual Instrument Technology

    Institute of Scientific and Technical Information of China (English)

    TANG Baoping; ZHONG Yuanchang; QIU Jianwei

    2006-01-01

    After analyzing and comparing the traditional automobile instrument, the onboard instrument based on virtual instrument technology is designed in this paper. The PC/104 computer was employed as the core processing unit of the onboard instrument, and the several intelligent data acquisition nodes are set and connected by the CAN bus, through which the nodes can communicate with the core processing unit. The information of the vehicle's working condition can be displayed synthetically by adopting virtual instrument technology. When the working condition goes beyond its limit, the system can emit an alarm, record and storage the abnormal condition automatically, and suggest how to deal with the abnormity urgently. The development background and design idea of onboard information system were elaborated in the paper. The software, the hardware architecture and the principle of onboard information system were introduced in detail.

  1. Future investigations onboard Soviet biosatellites of the Cosmos series.

    Science.gov (United States)

    Ilyin, E A

    1981-01-01

    Many rat experiments onboard Cosmos biosatellites have furnished information concerning the effects of weightlessness, artificial gravity, and ionizing radiation combined with weightlessness on structural and biochemical parameters of the animal body. The necessity to expand the scope of physiological investigations has led to the project of flight primate studies. It is planned to carry out the first primate experiments onboard the Cosmos biosatellite in 1982. At present investigations of weightlessness effects on the cardiovascular and vestibular systems, higher nervous activity, skeletal muscles and biorhythms of two rhesus monkeys are being developed and tested. It is also planned to conduct a study of weightlessness effects on embryogenesis of rats and bioenergetics of living systems onboard the same biosatellite. Further experiments onboard Cosmos biosatellites are planned.

  2. Position and orientation inference via on-board triangulation.

    Science.gov (United States)

    Advani, Madhu; Weile, Daniel S

    2017-01-01

    This work proposes a new approach to determine the spatial location and orientation of an object using measurements performed on the object itself. The on-board triangulation algorithm we outline could be implemented in lieu of, or in addition to, well-known alternatives such as Global Positioning System (GPS) or standard triangulation, since both of these correspond to significantly different geometric pictures and necessitate different hardware and algorithms. We motivate the theory by describing situations in which on-board triangulation would be useful and even preferable to standard methods. The on-board triangulation algorithm we outline involves utilizing dumb beacons which broadcast omnidirectional single frequency radio waves, and smart antenna arrays on the object itself to infer the direction of the beacon signals, which may be used for onboard calculation of the position and orientation of the object. Numerical examples demonstrate the utility of the method and its noise tolerance.

  3. Onboard Optical Navigation Measurement Processing in GEONS Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this IRAD is to establish in-house onboard OpNav measurement data processing capabilities through software development and testing.  Software...

  4. Performance assessment of onboard and scene-based methods for Airborne Prism Experiment spectral characterization.

    Science.gov (United States)

    D'Odorico, Petra; Guanter, Luis; Schaepman, Michael E; Schläpfer, Daniel

    2011-08-20

    Accurate spectral calibration of airborne and spaceborne imaging spectrometers is essential for proper preprocessing and scientific exploitation of high spectral resolution measurements of the land and atmosphere. A systematic performance assessment of onboard and scene-based methods for in-flight monitoring of instrument spectral calibration is presented for the first time in this paper. Onboard and ground imaging data were collected at several flight altitudes using the Airborne Prism Experiment (APEX) imaging spectrometer. APEX is equipped with an in-flight characterization (IFC) facility allowing the evaluation of radiometric, spectral, and geometric system properties, both in-flight and on-ground for the full field of view. Atmospheric and onboard filter spectral features present in at-sensor radiances are compared with the same features in reference transmittances convolved to varying instrument spectral configurations. A spectrum-matching algorithm, taking advantage of the high sensitivity of measurements around sharp spectral features toward spectrometer spectral performance, is used to retrieve channel center wavelength and bandwidth parameters. Results showed good agreement between spectral parameters estimated using onboard IFC and ground imaging data. The average difference between estimates obtained using the O(2) and H(2)O features and those obtained using the corresponding filter features amounted to about 0.3 nm (0.05 of a spectral pixel). A deviation from the nominal laboratory instrument spectral calibration and an altitude-dependent performance was additionally identified. The relatively good agreement between estimates obtained by the two approaches in similar spectral windows suggests they can be used in a complementary fashion: while the method relying on atmospheric features can be applied without the need for dedicated calibration acquisitions, the IFC allows assessment at user-selectable wavelength positions by custom filters as well as for

  5. 40 CFR 86.1806-04 - On-board diagnostics.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false On-board diagnostics. 86.1806-04..., and Complete Otto-Cycle Heavy-Duty Vehicles § 86.1806-04 On-board diagnostics. This § 86.1806-04... alternative to SAE J1850. (iii) ISO 15765-4.3:2001 “Road Vehicles-Diagnostics on Controller Area Network...

  6. 2014 Joint International Accelerator School: Beam Loss and Accelerator Protection

    CERN Document Server

    JAS - Joint US-CERN-Japan-Russia Accelerator School

    2016-01-01

    Many particle accelerators operate with very high beam power and very high energy stored in particle beams as well as in magnet systems. In the future, the beam power in high intensity accelerators will further increase. The protection of the accelerator equipment from the consequences of uncontrolled release of the energy is essential. This was the motivation for organizing a first school on beam losses and accelerator protection (in general referred to as machine protection). During the school the methods and technologies to identify, mitigate, monitor and manage the technical risks associated with the operation of accelerators with high-power beams or subsystems with large stored energy were presented. At the completion of the school the participants should have been able to understand the physical phenomena that can damage machine subsystems or interrupt operations and to analyze an accelerator facility to produce a register of technical risks and the corresponding risk mitigation and management strategie...

  7. Hardware and software for ground tests of onboard charged particle spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    Batischev, A. G., E-mail: Alexey-Batischev@mail.ru; Galper, A. M. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) (Russian Federation); Grishin, S. A. [Academy of Sciences of Belarus, Stepanov Institute of Physics, National (Belarus); Naumov, P. Yu. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) (Russian Federation); Niadvetski, N. S. [Academy of Sciences of Belarus, Stepanov Institute of Physics, National (Belarus)

    2015-12-15

    The article presents a hardware and software complex for ground tests of onboard charged particle spectrometers that are designed at the National Research Nuclear University MEPhI for monitoring of nuclear-physical factors of space weather and can be installed in a wide class of satellites. The structural scheme and operating principles of component parts are discussed. The main algorithm and software features are presented. The technique of ground spectrometer tests and calibrations in various measurement modes at atmospheric cosmic particle flows, both in autonomous laboratories and in interface tests as part of a satellite, is also described.

  8. An Onboard ISS Virtual Reality Trainer

    Science.gov (United States)

    Miralles, Evelyn

    2013-01-01

    Prior to the retirement of the Space Shuttle, many exterior repairs on the International Space Station (ISS) were carried out by shuttle astronauts, trained on the ground and flown to the Station to perform these specific repairs. With the retirement of the shuttle, this is no longer an available option. As such, the need for ISS crew members to review scenarios while on flight, either for tasks they already trained for on the ground or for contingency operations has become a very critical issue. NASA astronauts prepare for Extra-Vehicular Activities (EVA) or Spacewalks through numerous training media, such as: self-study, part task training, underwater training in the Neutral Buoyancy Laboratory (NBL), hands-on hardware reviews and training at the Virtual Reality Laboratory (VRLab). In many situations, the time between the last session of a training and an EVA task might be 6 to 8 months. EVA tasks are critical for a mission and as time passes the crew members may lose proficiency on previously trained tasks and their options to refresh or learn a new skill while on flight are limited to reading training materials and watching videos. In addition, there is an increased need for unplanned contingency repairs to fix problems arising as the Station ages. In order to help the ISS crew members maintain EVA proficiency or train for contingency repairs during their mission, the Johnson Space Center's VRLab designed an immersive ISS Virtual Reality Trainer (VRT). The VRT incorporates a unique optical system that makes use of the already successful Dynamic On-board Ubiquitous Graphics (DOUG) software to assist crew members with procedure reviews and contingency EVAs while on board the Station. The need to train and re-train crew members for EVAs and contingency scenarios is crucial and extremely demanding. ISS crew members are now asked to perform EVA tasks for which they have not been trained and potentially have never seen before. The Virtual Reality Trainer (VRT

  9. Investigation of obturator and ignitor effects on low velocity starting of the ram accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Knowlen, C.; Bundy, C.; Bruckner, A.P. [Washington Univ., Seattle, WA (United States). Aerospace and Energetics Research Program; Kruczynski, D. [Washington Univ., Seattle, WA (United States). Aerospace and Energetics Research Program; Utron Inc., Manassas, VA (United States)

    2000-11-01

    An experimental investigation of the effects of obturator geometry, propellant chemistry, and onboard pyrotechnic ignitor systems on the starting characteristics of the ram accelerator at low launch velocity has been conducted at the University of Washington 38-mm-bore facility. The ram accelerator was successfully started at entrance velocities as low as 760 m/s using stoichiometric methane/oxygen propellants with various levels of carbon dioxide dilution and obturator configurations at a fill pressure of 2.5 MPa. Experiments using an onboard pyrotechnic ignitor demonstrated that ignition of the propellant and starting of the ram accelerator could occur without the presence of the obturator-driven normal shock. (orig.)

  10. Horizontal Accelerator

    Data.gov (United States)

    Federal Laboratory Consortium — The Horizontal Accelerator (HA) Facility is a versatile research tool available for use on projects requiring simulation of the crash environment. The HA Facility is...

  11. Onboard Sensor Data Qualification in Human-Rated Launch Vehicles

    Science.gov (United States)

    Wong, Edmond; Melcher, Kevin J.; Maul, William A.; Chicatelli, Amy K.; Sowers, Thomas S.; Fulton, Christopher; Bickford, Randall

    2012-01-01

    The avionics system software for human-rated launch vehicles requires an implementation approach that is robust to failures, especially the failure of sensors used to monitor vehicle conditions that might result in an abort determination. Sensor measurements provide the basis for operational decisions on human-rated launch vehicles. This data is often used to assess the health of system or subsystem components, to identify failures, and to take corrective action. An incorrect conclusion and/or response may result if the sensor itself provides faulty data, or if the data provided by the sensor has been corrupted. Operational decisions based on faulty sensor data have the potential to be catastrophic, resulting in loss of mission or loss of crew. To prevent these later situations from occurring, a Modular Architecture and Generalized Methodology for Sensor Data Qualification in Human-rated Launch Vehicles has been developed. Sensor Data Qualification (SDQ) is a set of algorithms that can be implemented in onboard flight software, and can be used to qualify data obtained from flight-critical sensors prior to the data being used by other flight software algorithms. Qualified data has been analyzed by SDQ and is determined to be a true representation of the sensed system state; that is, the sensor data is determined not to be corrupted by sensor faults or signal transmission faults. Sensor data can become corrupted by faults at any point in the signal path between the sensor and the flight computer. Qualifying the sensor data has the benefit of ensuring that erroneous data is identified and flagged before otherwise being used for operational decisions, thus increasing confidence in the response of the other flight software processes using the qualified data, and decreasing the probability of false alarms or missed detections.

  12. Future accelerators

    CERN Document Server

    Hübner, K

    1999-01-01

    An overview of the various schemes for electron-positron linear colliders is given and the status of the development of key components and the various test facilities is given. The present studies of muon-muon colliders and very large hadron colliders are summarized including the plans for component development and tests. Accelerator research and development to achieve highest gradients in linear accelerators is outlined. (44 refs).

  13. Control system and environmental parameters monitoring of the Tandetron Accelerator clean room; Sistema de control y monitoreo de parametros ambientales del cuarto limpio del acelerador Tandetron

    Energy Technology Data Exchange (ETDEWEB)

    Mejia V, M.E.; Garcia H, J.M.; Flores M, J. [ININ, Departamento de Sistemas Electronicos, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: mmejia@nuclear.inin.mx

    2007-07-01

    A control system and monitoring of humidity and temperature implemented by means of a system based on a microcontroller, an intelligent sensor and a stage of power for the actuators handling is described. The change of the levels of reference of the control system and the monitoring of the physical controlled variables can be carried out from any connected computer to a local net or Internet. (Author)

  14. Verification of ICESat-2/ATLAS Science Receiver Algorithm Onboard Databases

    Science.gov (United States)

    Carabajal, C. C.; Saba, J. L.; Leigh, H. W.; Magruder, L. A.; Urban, T. J.; Mcgarry, J.; Schutz, B. E.

    2013-12-01

    NASA's ICESat-2 mission will fly the Advanced Topographic Laser Altimetry System (ATLAS) instrument on a 3-year mission scheduled to launch in 2016. ATLAS is a single-photon detection system transmitting at 532nm with a laser repetition rate of 10 kHz, and a 6 spot pattern on the Earth's surface. A set of onboard Receiver Algorithms will perform signal processing to reduce the data rate and data volume to acceptable levels. These Algorithms distinguish surface echoes from the background noise, limit the daily data volume, and allow the instrument to telemeter only a small vertical region about the signal. For this purpose, three onboard databases are used: a Surface Reference Map (SRM), a Digital Elevation Model (DEM), and a Digital Relief Maps (DRMs). The DEM provides minimum and maximum heights that limit the signal search region of the onboard algorithms, including a margin for errors in the source databases, and onboard geolocation. Since the surface echoes will be correlated while noise will be randomly distributed, the signal location is found by histogramming the received event times and identifying the histogram bins with statistically significant counts. Once the signal location has been established, the onboard Digital Relief Maps (DRMs) will be used to determine the vertical width of the telemetry band about the signal. University of Texas-Center for Space Research (UT-CSR) is developing the ICESat-2 onboard databases, which are currently being tested using preliminary versions and equivalent representations of elevation ranges and relief more recently developed at Goddard Space Flight Center (GSFC). Global and regional elevation models have been assessed in terms of their accuracy using ICESat geodetic control, and have been used to develop equivalent representations of the onboard databases for testing against the UT-CSR databases, with special emphasis on the ice sheet regions. A series of verification checks have been implemented, including

  15. Onboard Detection of Active Canadian Sulfur Springs: A Europa Analogue

    Science.gov (United States)

    Castano, Rebecca; Wagstaff, Kiri; Gleeson, Damhnait; Pappalardo, Robert; Chien, Steve; Tran, Daniel; Scharenbroich, Lucas; Moghaddam, Baback; Tang, Benyang; Bue, Brian; Doggett, Thomas; Mandl, Dan; Frye, Stuart

    2008-01-01

    We discuss a current, ongoing demonstration of insitu onboard detection in which the Earth Observing-1 spacecraft detects surface sulfur deposits that originate from underlying springs by distinguishing the sulfur from the ice-rich glacial background, a good analogue for the Europan surface. In this paper, we describe the process of developing the onboard classifier for detecting the presence of sulfur in a hyperspectral scene, including the use of a training/testing set that is not exhaustively labeled, i.e.not all true positives are marked, and the selection of 12, out of 242, Hyperion instrument wavelength bands to use in the onboard detector. This study aims to demonstrate the potential for future missions to capture short-lived science events, make decisions onboard, identify high priority data for downlink and perform onboard change detection. In the future, such capability could help maximize the science return of downlink bandwidth-limited missions, addressing a significant constraint in all deep-space missions.

  16. An Innovative On-Board Computer for Space Robot

    Institute of Scientific and Technical Information of China (English)

    WEI Ran; JIN Ming-he; XIA Jin-jun; LIU Hong

    2007-01-01

    In this paper an on-board computer system for the first Chinese Intelligent Space Robotic System was presented. A fault tolerance design on on-board computer (OBC) was proposed that allows commercial-off-theshelf (COTS) devices to be incorporated into dual processing modules of on-board computer. The processing module is composed of 32-bit ARM RISC processor and other COTS devices. This innovative approach deeply relies on light weight/low cost equipment development using commercial miniaturized parts and non-space qualified technologies. As well as, a set of fault handling mechanisms was implemented in the computer system. The on-board software was organized around a set of processes that communicate between each other through a routing process.The qualification experiment shows that the fault tolerant on-board computer has excellent data processing capability and is enough to meet the demanding of the extremely tight constraints on mass, volume, power consumption and space environmental conditions.

  17. The end-to-end testbed of the Optical Metrology System on-board LISA Pathfinder

    CERN Document Server

    Steier, Frank; Marín, Antonio F García; Gerardi, Domenico; Heinzel, Gerhard; Danzmann, Karsten; 10.1088/0264-9381/26/9/094010

    2012-01-01

    LISA Pathfinder is a technology demonstration mission for the Laser Interferometer Space Antenna (LISA). The main experiment on-board LISA Pathfinder is the so-called LISA Technology Package (LTP) which has the aim to measure the differential acceleration between two free-falling test masses with an accuracy of 3x10^(-14) ms^(-2)/sqrt[Hz] between 1 mHz and 30 mHz. This measurement is performed interferometrically by the Optical Metrology System (OMS) on-board LISA Pathfinder. In this paper we present the development of an experimental end-to-end testbed of the entire OMS. It includes the interferometer and its sub-units, the interferometer back-end which is a phasemeter and the processing of the phasemeter output data. Furthermore, 3-axes piezo actuated mirrors are used instead of the free-falling test masses for the characterisation of the dynamic behaviour of the system and some parts of the Drag-free and Attitude Control System (DFACS) which controls the test masses and the satellite. The end-to-end testbe...

  18. Charged Particle Monitor on the AstroSat mission

    CERN Document Server

    Rao, A R; Bhargava, Yash; Khanna, Rakesh; Hingar, M K; Kutty, A P K; Malkar, J P; Basak, Rupal; Sreekumar, S; Samuel, Essy; Priya, P; Vinod, P; Bhattacharya, D; Bhalerao, V; Vadawale, S V; Mithun, N P S; Pandiyan, R; Subbarao, K; Seetha, S; Sarma, K Suryanarayana

    2016-01-01

    Charged Particle Monitor (CPM) on-board the AstroSat satellite is an instrument designed to detect the flux of charged particles at the satellite location. A Cesium Iodide Thallium (CsI(Tl)) crystal is used with a Kapton window to detect protons with energies greater than 1 MeV. The ground calibration of CPM was done using gamma-rays from radioactive sources and protons from particle accelerators. Based on the ground calibration results, energy deposition above 1 MeV are accepted and particle counts are recorded. It is found that CPM counts are steady and the signal for the onset and exit of South Atlantic Anomaly (SAA) region are generated in a very reliable and stable manner.

  19. Charged Particle Monitor on the AstroSat Mission

    Indian Academy of Sciences (India)

    A. R. Rao; M. H. Patil; Yash Bhargava; Rakesh Khanna; M. K. Hingar; A. P. K. Kutty; J. P. Malkar; Rupal Basak; S. Sreekumar; Essy Samuel; P. Priya; P. Vinod; D. Bhattacharya; V. Bhalerao; S. V. Vadawale; N. P. S. Mithun; R. Pandiyan; K. Subbarao; S. Seetha; K. Suryanarayana Sarma

    2017-06-01

    Charged Particle Monitor (CPM) on-board the Astrosat satellite is an instrument designed to detect the flux of charged particles at the satellite location. A Cesium Iodide Thallium (CsI(Tl)) crystal is used with a Kapton window to detect protons with energies greater than 1 MeV. The ground calibration of CPM was done using gamma-rays from radioactive sources and protons from particle accelerators. Based on the ground calibration results, energy deposition above 1 MeV are accepted and particle counts are recorded. It is found that CPM counts are steady and the signal for the onset and exit of South Atlantic Anomaly (SAA) region are generated in a very reliable and stable manner.

  20. Critical analysis of the positioning of monitoring system of the cyclotron accelerator; Analise critica do posicionamento de um sistema de monitoramento de acelerador Ciclotron

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Julia A.; Passaro, Bruno M.; Guimaraes, Maria Ines C.C.; Buchpigue, Carlos A. [Centro de Medicina Nuclear (CMN) do InRad HCFMUSP, Sao Paulo, SP (Brazil); Videira, Heber S., E-mail: heber@cyclopet.com [CYCLOPET Radiofarmacos LTDA., Curitiba, PR (Brazil)

    2012-08-15

    Ever since the first concerns arose about the possibility that the ionizing radiation induced detriment to human health, were created the methods of production, characterization and measurement of radiation, as well as definition of quantities that realistically express its interaction with human tissue. From this point, the monitoring program of the installation of a cyclotron must be continuously performed and contain the critical points of contamination according to the CNEN standard N.E. 3.02 - Radioprotection Service to avoid contamination and maintain radioactive exposure rates as low as reasonably achievable. The results obtained during the analysis showed that the positioning of monitors is suitable, except for the physico-chemical control laboratory monitors, which were installed next to the chapel of manipulation and below the dose calibrator. The answer obtained from the monitoring system in the position that the ionization chamber is in the door of the bunker should be taken into account, because the intensity of radiation emitted by the activation of the targets is slightly attenuated by the cyclotron. (author)

  1. Air Quality Monitoring: Risk-Based Choices

    Science.gov (United States)

    James, John T.

    2009-01-01

    Air monitoring is secondary to rigid control of risks to air quality. Air quality monitoring requires us to target the credible residual risks. Constraints on monitoring devices are severe. Must transition from archival to real-time, on-board monitoring. Must provide data to crew in a way that they can interpret findings. Dust management and monitoring may be a major concern for exploration class missions.

  2. Fiber-Optic Network Architectures for Onboard Avionics Applications Investigated

    Science.gov (United States)

    Nguyen, Hung D.; Ngo, Duc H.

    2003-01-01

    This project is part of a study within the Advanced Air Transportation Technologies program undertaken at the NASA Glenn Research Center. The main focus of the program is the improvement of air transportation, with particular emphasis on air transportation safety. Current and future advances in digital data communications between an aircraft and the outside world will require high-bandwidth onboard communication networks. Radiofrequency (RF) systems, with their interconnection network based on coaxial cables and waveguides, increase the complexity of communication systems onboard modern civil and military aircraft with respect to weight, power consumption, and safety. In addition, safety and reliability concerns from electromagnetic interference between the RF components embedded in these communication systems exist. A simple, reliable, and lightweight network that is free from the effects of electromagnetic interference and capable of supporting the broadband communications needs of future onboard digital avionics systems cannot be easily implemented using existing coaxial cable-based systems. Fiber-optical communication systems can meet all these challenges of modern avionics applications in an efficient, cost-effective manner. The objective of this project is to present a number of optical network architectures for onboard RF signal distribution. Because of the emergence of a number of digital avionics devices requiring high-bandwidth connectivity, fiber-optic RF networks onboard modern aircraft will play a vital role in ensuring a low-noise, highly reliable RF communication system. Two approaches are being used for network architectures for aircraft onboard fiber-optic distribution systems: a hybrid RF-optical network and an all-optical wavelength division multiplexing (WDM) network.

  3. Onboard Science and Applications Algorithm for Hyperspectral Data Reduction

    Science.gov (United States)

    Chien, Steve A.; Davies, Ashley G.; Silverman, Dorothy; Mandl, Daniel

    2012-01-01

    An onboard processing mission concept is under development for a possible Direct Broadcast capability for the HyspIRI mission, a Hyperspectral remote sensing mission under consideration for launch in the next decade. The concept would intelligently spectrally and spatially subsample the data as well as generate science products onboard to enable return of key rapid response science and applications information despite limited downlink bandwidth. This rapid data delivery concept focuses on wildfires and volcanoes as primary applications, but also has applications to vegetation, coastal flooding, dust, and snow/ice applications. Operationally, the HyspIRI team would define a set of spatial regions of interest where specific algorithms would be executed. For example, known coastal areas would have certain products or bands downlinked, ocean areas might have other bands downlinked, and during fire seasons other areas would be processed for active fire detections. Ground operations would automatically generate the mission plans specifying the highest priority tasks executable within onboard computation, setup, and data downlink constraints. The spectral bands of the TIR (thermal infrared) instrument can accurately detect the thermal signature of fires and send down alerts, as well as the thermal and VSWIR (visible to short-wave infrared) data corresponding to the active fires. Active volcanism also produces a distinctive thermal signature that can be detected onboard to enable spatial subsampling. Onboard algorithms and ground-based algorithms suitable for onboard deployment are mature. On HyspIRI, the algorithm would perform a table-driven temperature inversion from several spectral TIR bands, and then trigger downlink of the entire spectrum for each of the hot pixels identified. Ocean and coastal applications include sea surface temperature (using a small spectral subset of TIR data, but requiring considerable ancillary data), and ocean color applications to track

  4. Accelerated Unification

    OpenAIRE

    Arkani-Hamed, Nima; Cohen, Andrew; Georgi, Howard

    2001-01-01

    We construct four dimensional gauge theories in which the successful supersymmetric unification of gauge couplings is preserved but accelerated by N-fold replication of the MSSM gauge and Higgs structure. This results in a low unification scale of $10^{13/N}$ TeV.

  5. On-board Unit and its Possibilities of Communications on Safety and Security Principles

    Directory of Open Access Journals (Sweden)

    Martin Vestenicky

    2008-01-01

    Full Text Available The technical solution of on-board unit (OBU for vehicles used for dangerous good transport and design of vehicle sensor network (based on CAN bus for dangerous good monitoring will be discussed. In presentation the conception of GSM/GPRS networking subsystem for real time data transmission into monitoring centre will be described. Next themes of discussion will be focused on the possibilities of solution of safety-related communication channel for safety sensor network in accordance with standard for functional safety of Electrical / Electronic / Programmable Electronic (E/E/PE systems IEC 61508, recommended methods of risk analysis and possibilities of their modelling and proposal of secure communication channel over GSM/GPRS for secure data transmission into control centre on the base of IPsec protocol.

  6. Particle Accelerators in China

    Science.gov (United States)

    Zhang, Chuang; Fang, Shouxian

    As the special machines that can accelerate charged particle beams to high energy by using electromagnetic fields, particle accelerators have been widely applied in scientific research and various areas of society. The development of particle accelerators in China started in the early 1950s. After a brief review of the history of accelerators, this article describes in the following sections: particle colliders, heavy-ion accelerators, high-intensity proton accelerators, accelerator-based light sources, pulsed power accelerators, small scale accelerators, accelerators for applications, accelerator technology development and advanced accelerator concepts. The prospects of particle accelerators in China are also presented.

  7. MUON ACCELERATION

    Energy Technology Data Exchange (ETDEWEB)

    BERG,S.J.

    2003-11-18

    One of the major motivations driving recent interest in FFAGs is their use for the cost-effective acceleration of muons. This paper summarizes the progress in this area that was achieved leading up to and at the FFAG workshop at KEK from July 7-12, 2003. Much of the relevant background and references are also given here, to give a context to the progress we have made.

  8. 75 FR 68189 - Crewmember Requirements When Passengers are Onboard

    Science.gov (United States)

    2010-11-05

    ... receptacle fire extinguishers, and Halon 1211 extinguishers; Improving cabin interior flammability standards... air carriers to limit the size and amount of carry-on baggage that each passenger may bring onboard... spent by the substituting flightcrew member applies towards daily duty time limits and is...

  9. Estimation of waves and ship responses using onboard measurements

    DEFF Research Database (Denmark)

    Montazeri, Najmeh

    This thesis focuses on estimation of waves and ship responses using ship-board measurements. This is useful for development of operational safety and performance efficiency in connection with the broader concept of onboard decision support systems. Estimation of sea state is studied using a set...

  10. The "SCORPION" experiment onboard the International Space Station. Preliminary results.

    Science.gov (United States)

    Borisov, V; Deshevaya, E; Grachov, E; Grigoryan, O; Tchurilo, I; Tsetlin, V

    2003-01-01

    The "SCORPION" program onboard the Russian Segment (RS) of the International Space Station (ISS) is designed to carry out complex research of the effects of the nar-Earth space parameters on the conditions under which various experiments and operations are being conducted. Special attention in this program was paid to the biological objects onboard the orbital station, e.g. it was found that variation in the number of colony forming units (micromicets and bacteria) correlates with the solar activity and the absorbed dose. The "SCORPION" experiment onboard the RS ISS started in January 2002. It was designed to measure the following parameters inside the space absorbed doses in different places inside the RS ISS, the fluxes of energetic charged particles, neutrons and gamma-quanta; the vectors of the magnetic field and low-frequency electromagnetic waves. At the same time the growth of micromicets on the samples of various materials was studied. The description of the "SCORPION" experiment and the preliminary results obtained onboard the RS ISS in 2002 are presented.

  11. Onboard Processing and Autonomous Operations on the IPEX Cubesat

    Science.gov (United States)

    Chien, Steve; Doubleday, Joshua; Ortega, Kevin; Flatley, Tom; Crum, Gary; Geist, Alessandro; Lin, Michael; Williams, Austin; Bellardo, John; Puig-Suari, Jordi; Stanton, Eric; Yee, Edmond

    2012-01-01

    IPEX is a 1u Cubesat sponsored by NASA Earth Science Technology Office (ESTO), the goals or which are: (1) Flight validate high performance flight computing, (2) Flight validate onboard instrument data processing product generation software, (3) flight validate autonomous operations for instrument processing, (4) enhance NASA outreach and university ties.

  12. Dual Accelerometer Usage Strategy for Onboard Space Navigation

    Science.gov (United States)

    Zanetti, Renato; D'Souza, Chris

    2012-01-01

    This work introduces a dual accelerometer usage strategy for onboard space navigation. In the proposed algorithm the accelerometer is used to propagate the state when its value exceeds a threshold and it is used to estimate its errors otherwise. Numerical examples and comparison to other accelerometer usage schemes are presented to validate the proposed approach.

  13. Onboard photo: Astronaut Mae Jemison working in Spacelab-J

    Science.gov (United States)

    1992-01-01

    Space Shuttle Endeavour (STS-47) onboard photo of Astronaut Mae Jemison working in Spacelab-J module. Spacelab-J is a combined National Space Development Agency of Japan (NASDA) and NASA mission. The objectives included life sciences, microgravity and technology research.

  14. Real-time Java for on-board systems

    Science.gov (United States)

    Cechticky, V.; Pasetti, A.

    2002-07-01

    The Java language has several attractive features but cannot at present be used in on-board systems primarily because it lacks support for hard real-time operation. This shortcoming is in being addressed: some suppliers are already providing implementations of Java that are RT-compliant; Sun Microsystem has approved a formal specification for a real-time extension of the language; and an independent consortium is working on an alternative specification for real-time Java. It is therefore expected that, within a year or so, standardized commercial implementations of real-time Java will be on the market. Availability of real-time implementations now opens the way to its use on-board. Within this context, this paper has two objectives. Firstly, it discusses the suitability of Java for on-board applications. Secondly, it reports the results of an ESA study to port a software framework for on-board control systems to a commercial real-time version of Java.

  15. Laser acceleration

    Science.gov (United States)

    Tajima, T.; Nakajima, K.; Mourou, G.

    2017-02-01

    The fundamental idea of Laser Wakefield Acceleration (LWFA) is reviewed. An ultrafast intense laser pulse drives coherent wakefield with a relativistic amplitude robustly supported by the plasma. While the large amplitude of wakefields involves collective resonant oscillations of the eigenmode of the entire plasma electrons, the wake phase velocity ˜ c and ultrafastness of the laser pulse introduce the wake stability and rigidity. A large number of worldwide experiments show a rapid progress of this concept realization toward both the high-energy accelerator prospect and broad applications. The strong interest in this has been spurring and stimulating novel laser technologies, including the Chirped Pulse Amplification, the Thin Film Compression, the Coherent Amplification Network, and the Relativistic Mirror Compression. These in turn have created a conglomerate of novel science and technology with LWFA to form a new genre of high field science with many parameters of merit in this field increasing exponentially lately. This science has triggered a number of worldwide research centers and initiatives. Associated physics of ion acceleration, X-ray generation, and astrophysical processes of ultrahigh energy cosmic rays are reviewed. Applications such as X-ray free electron laser, cancer therapy, and radioisotope production etc. are considered. A new avenue of LWFA using nanomaterials is also emerging.

  16. On-Board Mining in the Sensor Web

    Science.gov (United States)

    Tanner, S.; Conover, H.; Graves, S.; Ramachandran, R.; Rushing, J.

    2004-12-01

    On-board data mining can contribute to many research and engineering applications, including natural hazard detection and prediction, intelligent sensor control, and the generation of customized data products for direct distribution to users. The ability to mine sensor data in real time can also be a critical component of autonomous operations, supporting deep space missions, unmanned aerial and ground-based vehicles (UAVs, UGVs), and a wide range of sensor meshes, webs and grids. On-board processing is expected to play a significant role in the next generation of NASA, Homeland Security, Department of Defense and civilian programs, providing for greater flexibility and versatility in measurements of physical systems. In addition, the use of UAV and UGV systems is increasing in military, emergency response and industrial applications. As research into the autonomy of these vehicles progresses, especially in fleet or web configurations, the applicability of on-board data mining is expected to increase significantly. Data mining in real time on board sensor platforms presents unique challenges. Most notably, the data to be mined is a continuous stream, rather than a fixed store such as a database. This means that the data mining algorithms must be modified to make only a single pass through the data. In addition, the on-board environment requires real time processing with limited computing resources, thus the algorithms must use fixed and relatively small amounts of processing time and memory. The University of Alabama in Huntsville is developing an innovative processing framework for the on-board data and information environment. The Environment for On-Board Processing (EVE) and the Adaptive On-board Data Processing (AODP) projects serve as proofs-of-concept of advanced information systems for remote sensing platforms. The EVE real-time processing infrastructure will upload, schedule and control the execution of processing plans on board remote sensors. These plans

  17. Crucial Component Damage Detection, Monitoring and Mitigation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR project delivers an on-board structural health-monitoring (SHM) system with embedded sensors that sense mechanical impedance deviations to flag incipient...

  18. High-Performance Contaminant Monitor for Spacecraft Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Vision for Space Exploration demands increasing reliance on real-time trace gas monitors onboard spacecraft. Present grab samples and badges will be inadequate...

  19. Accelerators and the Accelerator Community

    Energy Technology Data Exchange (ETDEWEB)

    Malamud, Ernest; Sessler, Andrew

    2008-06-01

    In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

  20. The on-board data handling concept for the LOFT Large Area Detector

    CERN Document Server

    Suchy, S; Tenzer, C; Santangelo, A; Argan, A; Feroci, M; Kennedy, T E; Smith, P J; Walton, D; Zane, S; Portell, J; García-Berro, E

    2012-01-01

    The Large Observatory for X-ray Timing (LOFT) is one of the four candidate ESA M3 missions considered for launch in the time-frame of 2022. It is specifically designed to perform fast X-ray timing and probe the status of the matter near black holes and neutron stars. The LOFT scientific payload consists of a Large Area Detector and a Wide Field Monitor. The LAD is a 10 m^2-class pointed instrument with high spectral (200 eV @ 6 keV) and timing (< 10 {\\mu}s) resolution over the 2-80 keV range. It is designed to observe persistent and transient X-ray sources with a very large dynamic range from a few mCrab up to an intensity of 15 Crab. An unprecedented large throughput (~280.000 cts/s from the Crab) is achieved with a segmented detector, making pile-up and dead-time, often worrying or limiting focused experiments, secondary issues. We present the on-board data handling concept that follows the highly segmented and hierarchical structure of the instrument from the front-end electronics to the on-board softwa...

  1. Evolved Acceleration Guidance for Planetary Entry

    Science.gov (United States)

    Mease, K. D.; Leavitt, J. A.; Ferch, M.

    The U.S. Apollo and Shuttle programs have proven the viability and effectiveness of acceleration guidance. New capabilities have been developed to augment this basic concept. Algorithms have been designed for low lift to drag ratio vehicles and for mid to high lift to drag ratio vehicles. These algorithms have been tested for Mars landing and for earth entry of reusable launch vehicles and have performed well in both cases. Also the trajectory planner has been incorporated into a landing footprint generator that is designed for on-board use.

  2. Portable Simulator for On-Board International Space Station Emergency Training

    Science.gov (United States)

    Bolt, Kathy; Root, Michael

    2014-01-01

    The crew on-board the International Space Station (ISS) have to be prepared for any possible emergency. The emergencies of most concern are a fire, depressurization or a toxic atmosphere. The crew members train on the ground before launch but also need to practice their emergency response skills while they are on orbit for 6 months. On-Board Training (OBT) events for emergency response proficiency used to require the crew and ground teams to use paper "scripts" that showed the path through the emergency procedures. This was not very realistic since the participants could read ahead and never deviate from this scripted path. The new OBT emergency simulator allows the crew to view dynamic information on an iPad only when it would become available during an event. The simulator interface allows the crew member to indicate hatch closures, don and doff masks, read pressures, and sample smoke or atmosphere levels. As the crew executes their actions using the on-board simulator, the ground teams are able to monitor those actions via ground display data flowing through the ISS Ku Band communication system which syncs the on-board simulator software with a ground simulator which is accessible in all the control centers. The OBT Working Group (OBT WG), led by the Chief Training Office (CTO) at Johnson Space center is a Multilateral working group with partners in Russia, Japan, Germany and U.S.A. The OBTWG worked together to create a simulator based on these principles: (a) Create a dynamic simulation that gives real-time data feedback; (b) Maintain real-time interface between Mission Control Centers and crew during OBTs; (c) Provide flexibility for decision making during drill execution; (d) Materially reduce Instructor and Flight Control Team man-hour costs involved with developing, updating, and maintaining emergency OBT cases/scenarios; and (e) Introduce an element of surprise to emergency scenarios so the team can't tell the outcome of the case by reading ahead in a

  3. accelerating cavity

    CERN Multimedia

    On the inside of the cavity there is a layer of niobium. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment.

  4. Impact accelerations

    Science.gov (United States)

    Vongierke, H. E.; Brinkley, J. W.

    1975-01-01

    The degree to which impact acceleration is an important factor in space flight environments depends primarily upon the technology of capsule landing deceleration and the weight permissible for the associated hardware: parachutes or deceleration rockets, inflatable air bags, or other impact attenuation systems. The problem most specific to space medicine is the potential change of impact tolerance due to reduced bone mass and muscle strength caused by prolonged weightlessness and physical inactivity. Impact hazards, tolerance limits, and human impact tolerance related to space missions are described.

  5. 40 CFR 85.2207 - On-board diagnostics test standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false On-board diagnostics test standards... Warranty Short Tests § 85.2207 On-board diagnostics test standards. (a) (b) A vehicle shall fail the on-board diagnostics test if it is a 1996 or newer vehicle and the vehicle connector is missing, has...

  6. 49 CFR 395.15 - Automatic on-board recording devices.

    Science.gov (United States)

    2010-10-01

    ... certifying that the design of the automatic on-board recorder has been sufficiently tested to meet the... 49 Transportation 5 2010-10-01 2010-10-01 false Automatic on-board recording devices. 395.15... OF SERVICE OF DRIVERS § 395.15 Automatic on-board recording devices. (a) Applicability and...

  7. A Novel Permanent Magnetic Angular Acceleration Sensor

    OpenAIRE

    Hao Zhao; Hao Feng

    2015-01-01

    Angular acceleration is an important parameter for status monitoring and fault diagnosis of rotary machinery. Therefore, we developed a novel permanent magnetic angular acceleration sensor, which is without rotation angle limitations and could directly measure the instantaneous angular acceleration of the rotating system. The sensor rotor only needs to be coaxially connected with the rotating system, which enables convenient sensor installation. For the cup structure of the sensor rotor, it h...

  8. Development of Onboard Computer Complex for Russian Segment of ISS

    Science.gov (United States)

    Branets, V.; Brand, G.; Vlasov, R.; Graf, I.; Clubb, J.; Mikrin, E.; Samitov, R.

    1998-01-01

    Report present a description of the Onboard Computer Complex (CC) that was developed during the period of 1994-1998 for the Russian Segment of ISS. The system was developed in co-operation with NASA and ESA. ESA developed a new computation system under the RSC Energia Technical Assignment, called DMS-R. The CC also includes elements developed by Russian experts and organizations. A general architecture of the computer system and the characteristics of primary elements of this system are described. The system was integrated at RSC Energia with the participation of American and European specialists. The report contains information on software simulators, verification and de-bugging facilities witch were been developed for both stand-alone and integrated tests and verification. This CC serves as the basis for the Russian Segment Onboard Control Complex on ISS.

  9. Experimental study on ceramic membrane technology for onboard oxygen generation

    Institute of Scientific and Technical Information of China (English)

    Jiang Dongsheng; Bu Xueqin; Sun Bing; Lin Guiping; Zhao Hongtao; Cai Yan; Fang Ling

    2016-01-01

    The ceramic membrane oxygen generation technology has advantages of high concentra-tion of produced oxygen and potential nuclear and biochemical protection capability. The present paper studies the ceramic membrane technology for onboard oxygen generation. Comparisons are made to have knowledge of the effects of two kinds of ceramic membrane separation technologies on oxygen generation, namely electricity driven ceramic membrane separation oxygen generation technology (EDCMSOGT) and pressure driven ceramic membrane separation oxygen generation technology (PDCMSOGT). Experiments were conducted under different temperatures, pressures of feed air and produced oxygen flow rates. On the basis of these experiments, the flow rate of feed air, electric power provided, oxygen recovery rate and concentration of produced oxygen are compared under each working condition. It is concluded that the EDCMSOGT is the oxygen generation means more suitable for onboard conditions.

  10. Experimental study on ceramic membrane technology for onboard oxygen generation

    Directory of Open Access Journals (Sweden)

    Jiang Dongsheng

    2016-08-01

    Full Text Available The ceramic membrane oxygen generation technology has advantages of high concentration of produced oxygen and potential nuclear and biochemical protection capability. The present paper studies the ceramic membrane technology for onboard oxygen generation. Comparisons are made to have knowledge of the effects of two kinds of ceramic membrane separation technologies on oxygen generation, namely electricity driven ceramic membrane separation oxygen generation technology (EDCMSOGT and pressure driven ceramic membrane separation oxygen generation technology (PDCMSOGT. Experiments were conducted under different temperatures, pressures of feed air and produced oxygen flow rates. On the basis of these experiments, the flow rate of feed air, electric power provided, oxygen recovery rate and concentration of produced oxygen are compared under each working condition. It is concluded that the EDCMSOGT is the oxygen generation means more suitable for onboard conditions.

  11. Some recent measurements onboard spacecraft with passive detector.

    Science.gov (United States)

    Spurný, F; Jadrníĉková, I

    2005-01-01

    Several passive detectors were used to estimate dosimetry and microdosimetry characteristics of radiation field onboard spacecraft, namely: thermoluminescent detectors (TLDs), mainly to appreciate the contribution of radiation with low-linear energy transfer (LET); Si diode, to try to establish the contribution of fast neutrons; an LET spectrometer based on the chemically etched polyallyldiglycolcarbonate etched track detectors (PADC-TEDs). Detectors have been exposed onboard MIR and International Space Station (ISS) since 1997, they were also used during the MESSAGE 2 biological experiment, October 2003. The results are presented, analysed and discussed. Particular attention is devoted to the possibility of estimating neutron contribution based on data obtained with PADC-TED spectrometer of LET.

  12. Calibration and in orbit performance of the reflection grating spectrometer onboard XMM-Newton

    CERN Document Server

    de Vries, C P; Gabriel, C; Gonzalez-Riestra, R; Ibarra, A; Kaastra, J S; Pollock, A M T; Raassen, A J J; Paerels, F B S

    2014-01-01

    Context: XMM-Newton was launched on 10 December 1999 and has been operational since early 2000. One of the instruments onboard XMM-Newton is the reflection grating spectrometer (RGS). Two identical RGS instruments are available, with each RGS combining a reflection grating assembly (RGA) and a camera with CCDs to record the spectra. Aims: We describe the calibration and in-orbit performance of the RGS instrument. By combining the preflight calibration with appropriate inflight calibration data including the changes in detector performance over time, we aim at profound knowledge about the accuracy in the calibration. This will be crucial for any correct scientific interpretation of spectral features for a wide variety of objects. Methods: Ground calibrations alone are not able to fully characterize the instrument. Dedicated inflight measurements and constant monitoring are essential for a full understanding of the instrument and the variations of the instrument response over time. Physical models of the instru...

  13. Design Through Integration of On-Board Calibration Device with Imaging Spectroscopy Instruments

    Science.gov (United States)

    Stange, Michael

    2012-01-01

    The main purpose of the Airborne Visible and Infrared Imaging Spectroscopy (AVIRIS) project is to "identify, measure, and monitor constituents of the Earth's surface and atmosphere based on molecular absorption and particle scattering signatures." The project designs, builds, and tests various imaging spectroscopy instruments that use On-Board Calibration devices (OBC) to check the accuracy of the data collected by the spectrometers. The imaging instrument records the spectral signatures of light collected during flight. To verify the data is correct, the OBC shines light which is collected by the imaging spectrometer and compared against previous calibration data to track spectral response changes in the instrument. The spectral data has the calibration applied to it based on the readings from the OBC data in order to ensure accuracy.

  14. Advanced stellar compass - Onboard autonomous orbit determination, preliminary performance

    DEFF Research Database (Denmark)

    Betto, Maurizio; Jørgensen, John Leif; Jørgensen, Peter Siegbjørn

    2004-01-01

    of this instrument, the authors have devised a method to determine the orbit of a spacecraft autonomously, onboard, and without a priori knowledge of any kind. The solution is robust and fast. This paper presents the preliminary performance obtained during the ground testing in August 2002 at the Mauna Kea...... be implemented into an ASC without degrading the attitude measurements; and (4) to identify the areas of development and consolidation. The results obtained are very encouraging....

  15. Virtualizing Super-Computation On-Board Uas

    Science.gov (United States)

    Salami, E.; Soler, J. A.; Cuadrado, R.; Barrado, C.; Pastor, E.

    2015-04-01

    Unmanned aerial systems (UAS, also known as UAV, RPAS or drones) have a great potential to support a wide variety of aerial remote sensing applications. Most UAS work by acquiring data using on-board sensors for later post-processing. Some require the data gathered to be downlinked to the ground in real-time. However, depending on the volume of data and the cost of the communications, this later option is not sustainable in the long term. This paper develops the concept of virtualizing super-computation on-board UAS, as a method to ease the operation by facilitating the downlink of high-level information products instead of raw data. Exploiting recent developments in miniaturized multi-core devices is the way to speed-up on-board computation. This hardware shall satisfy size, power and weight constraints. Several technologies are appearing with promising results for high performance computing on unmanned platforms, such as the 36 cores of the TILE-Gx36 by Tilera (now EZchip) or the 64 cores of the Epiphany-IV by Adapteva. The strategy for virtualizing super-computation on-board includes the benchmarking for hardware selection, the software architecture and the communications aware design. A parallelization strategy is given for the 36-core TILE-Gx36 for a UAS in a fire mission or in similar target-detection applications. The results are obtained for payload image processing algorithms and determine in real-time the data snapshot to gather and transfer to ground according to the needs of the mission, the processing time, and consumed watts.

  16. Onboarding for Pathology Residency Programs—The Montefiore Experience

    Directory of Open Access Journals (Sweden)

    Tiffany Michele Hébert MD

    2016-03-01

    Full Text Available Onboarding is a system frequently used in the corporate world as a means of orienting incoming employees to their duties and inculcating the workplace values. The program aims to facilitate transition into new work roles and improve employee retention rates. At Montefiore, we have instituted an onboarding curriculum that is given to new anatomic and clinical pathology residents about a month prior to the start of residency. The program includes an introductory video series of basic histology and a series of anatomic and clinical case studies illustrating basic laboratory principles. This didactic content is tagged to learning objectives and short self-assessment modules. In addition, content related to the work ethos at Montefiore and the role of the core competencies and milestones in residency education are included. Finally, a broader component of the onboarding gives the incoming residents a social welcome to our area, including key information about living in the area surrounding Montefiore. The program has been well received by our residents for whom the content has helped to boost confidence when starting. We feel that the program is helpful in ensuring that all incoming residents start having received the same baseline didactic content. Transmitting this didactic content via onboarding allows our residents to begin the work of learning pathology immediately, rather than spending the first weeks of residency covering remedial content such as basic histology. Such a program may be useful to other pathology residencies, most of whom have residents from a range of backgrounds and whose prior exposure to pathology may be limited.

  17. Improving multispectral satellite image compression using onboard subpixel registration

    Science.gov (United States)

    Albinet, Mathieu; Camarero, Roberto; Isnard, Maxime; Poulet, Christophe; Perret, Jokin

    2013-09-01

    Future CNES earth observation missions will have to deal with an ever increasing telemetry data rate due to improvements in resolution and addition of spectral bands. Current CNES image compressors implement a discrete wavelet transform (DWT) followed by a bit plane encoding (BPE) but only on a mono spectral basis and do not profit from the multispectral redundancy of the observed scenes. Recent CNES studies have proven a substantial gain on the achievable compression ratio, +20% to +40% on selected scenarios, by implementing a multispectral compression scheme based on a Karhunen Loeve transform (KLT) followed by the classical DWT+BPE. But such results can be achieved only on perfectly registered bands; a default of registration as low as 0.5 pixel ruins all the benefits of multispectral compression. In this work, we first study the possibility to implement a multi-bands subpixel onboard registration based on registration grids generated on-the-fly by the satellite attitude control system and simplified resampling and interpolation techniques. Indeed bands registration is usually performed on ground using sophisticated techniques too computationally intensive for onboard use. This fully quantized algorithm is tuned to meet acceptable registration performances within stringent image quality criteria, with the objective of onboard real-time processing. In a second part, we describe a FPGA implementation developed to evaluate the design complexity and, by extrapolation, the data rate achievable on a spacequalified ASIC. Finally, we present the impact of this approach on the processing chain not only onboard but also on ground and the impacts on the design of the instrument.

  18. New Imaging Instrument Onboard the WSO-UV

    Science.gov (United States)

    Sachkov, M.; Shustov, B.; Gómez de Castro, A. I.; Shugarov, A.; Savanov, I.; Kanev, E.; Sichevskij, S.; Zvereva, M.

    2017-06-01

    We present here the new imaging instrument onboard the WSO-UV (World Space Observatory - Ultraviolet) project for observations in the UV (115-310 nm) spectral range. Dedicated to spectroscopic and imaging observations of the ultraviolet sky, the World Space Observatory - Ultraviolet mission is a Russian-Spanish collaboration with potential Mexican minor contribution. This paper provides the key scientific drivers of the instrument.

  19. Study on Software Fault Injection Based on Onboard System

    Institute of Scientific and Technical Information of China (English)

    PENGJunjie; HONGBingrong; YUANChengjun; LIAiguo; WEIZhenhua; QIAOYongqiang

    2005-01-01

    Fault injection techniques are the effective methods to evaluate the dependability and validate the fault tolerance mechanisms of computer systems. Among the different fault injection techniques, software implemented fault injection technique is regarded as one of the most promising technique for evaluation of the dependability of computer systems. In this paper, combined the advantages of software fault injection and the particularity of onboard system, a new software fault injection model, which can be used to evaluate the dependability and validate the fault tolerance mechanisms of the onboard system, is put forward. To evaluate the dependability of on boardsystem effectively, the application algorithm on how to use the model is presented. The experimental results show that using the fault injection model and algorithm put forward in this paper, not only most of low-level faults such as processor register faults, memory faults and so on can be injected, but also some high-level faults such as code faults, branch faults etc. can be injected, which can be used to evaluate the dependability of the onboard systems.

  20. Scheduling Onboard Processing for the Proposed HyspIRI Mission

    Science.gov (United States)

    Chien, Steve; Mclaren, David; Rabideau, Gregg; Mandl, Daniel; Hengemihle, Jerry

    2011-01-01

    The proposed Hyspiri mission is evaluating a X-band Direct Broadcast (DB) capability that would enable data to be delivered to ground stations virtually as it is acquired. However the HyspIRI VSWIR and TIR instruments will produce 1 Gbps data while the DB capability is 15 M bps for a 60x oversubscription. In order to address this data volume mismatch a DB concept has been developed thatdetermines which data to downlink based on both: 1. The type of surface the spacecraft is overflying and 2. Onboard processing of the data to detect events. For example when the spacecraft is overflying polar regions it might downlink a snow/ice product. Additionally the onboard software will search for thermal signatures indicative of a volcanic event or wild fire and downlink summary information (extent, spectra) when detected. The process of determining which products to generate when, based on request prioritization and onboard processing and downlink constraints is inherently a prioritized scheduling problem - we describe work to develop an automated solution to this problem.

  1. An Autonomous Onboard Targeting Algorithm Using Finite Thrust Maneuvers

    Science.gov (United States)

    Scarritt, Sara K.; Marchand, Belinda G.; Brown, Aaron J.; Tracy, William H.; Weeks, Michael W.

    2010-01-01

    In earlier investigations, the adaptation and implementation of a modified two-level corrections (or targeting) process as the onboard targeting algorithm for the Trans-Earth Injection phase of Orion is presented. The objective of that targeting algorithm is to generate the times of ignition and magnitudes of the required maneuvers such that the desired state at entry interface is achieved. In an actual onboard flight software implementation, these times of ignition and maneuvers are relayed onto Flight Control for command and execution. Although this process works well when the burn durations or burn arcs are small, this might not be the case during a contingency situation when lower thrust engines are employed to perform the maneuvers. Therefore, a new model for the two-level corrections process is formulated here to accommodate finite burn arcs. This paper presents the development and formulation of the finite burn two-level corrector, used as an onboard targeting algorithm for the Trans-Earth Injection phase of Orion. A performance comparison between the impulsive and finite burn models is also presented. The present formulation ensures all entry constraints are met, without violating the available fuel budget, while allowing for low-thrust scenarios with long burn durations.

  2. An Autonomous Onboard Targeting Algorithm Using Finite Thrust Maneuvers

    Science.gov (United States)

    Scarritt, Sara K.; Marchand, Belinda G.; Weeks, Michael W.

    2009-01-01

    In earlier investigations, the adaptation and implementation of a modified two-level corrections process as the onboard targeting algorithm for the Trans-Earth Injection phase of Orion is presented. The objective of that targeting algorithm is to generate the times of ignition and magnitudes of the required maneuvers such that the desired state at entry interface is achieved. In an actual onboard flight software implementation, these times of ignition and maneuvers are relayed onto Flight Control for command and execution. Although this process works well when the burn durations or burn arcs are small, this might not be the case during a contingency situation when lower thrust engines are employed to perform the maneuvers. Therefore, a new version of the modified two-level corrections process is formulated to handle the case of finite burn arcs. This paper presents the development and formulation of that finite burn modified two-level corrections process which can again be used as an onboard targeting algorithm for the Trans-Earth Injection phase of Orion. Additionally, performance results and a comparison between the two methods are presented. The finite burn two-level corrector formulation presented here ensures the entry constraints at entry interface are still met without violating the available fuel budget, while still accounting for much longer burn times in its design.

  3. On-board gaseous emissions of LPG taxis and estimation of taxi fleet emissions.

    Science.gov (United States)

    Lau, Jason; Hung, W T; Cheung, C S

    2011-11-15

    Instantaneous CO, NO, and HC emissions and exhaust flow rates from four LPG taxis, which adhered to Euro 2-4 emission standards, were measured using a sophisticated portable emission measurement system (PEMS). Instantaneous air/fuel ratios, emission rates, and emission factors at different operating modes were derived to explore the emission characteristics of these four taxis. Results show that gaseous emissions from these four taxis exceed emission standards, due to extended vehicle use and poor maintenance. NO emissions from newer taxis are lower whilst CO and HC emissions of the Euro 4 taxi are similar to those of Euro 2 taxis during idling and low speed travel. The taxis emit lower amounts of gaseous pollutants whilst idling and emit the highest amounts of CO and NO whilst accelerating. Large fluctuations in air/fuel ratios can be observed from the Euro 4 taxi during idling, indicating a malfunction of fuel supply control to the engine. Such fluctuations are not observed from the other taxis. This shows that a Euro 4 taxi is not necessarily cleaner than a Euro 3 taxi. Emission factors derived from on-board measurements are applied to estimate gaseous emissions from the taxi fleet; these results show that emissions are higher during peak hour traffic conditions. An estimate of the taxi fleet's emissions whilst the older taxis are replaced is also calculated. It can be seen that faster replacement of older taxis can lead to reductions in gaseous emissions from the taxi fleet. This study shows that the PEMS is an adequate tool for measuring emissions from LPG vehicles and that there is an urgent need to enforce emission standards on taxis. This study also shows that on-board measurements should be incorporated in the estimation of emissions from other vehicle types. This would result in better emission estimations under local traffic conditions. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. SVOM Gamma Ray Monitor

    CERN Document Server

    Dong, Yongwei; Li, Yanguo; Zhang, Yongjie; Zhang, Shuangnan

    2009-01-01

    The Space-based multi-band astronomical Variable Object Monitor (SVOM) mission is dedicated to the detection, localization and broad-band study of Gamma-Ray Bursts (GRBs) and other high-energy transient phenomena. The Gamma Ray Monitor (GRM) onboard is designed to observe the GRBs up to 5 MeV. With this instrument one of the key GRB parameter, Epeak, can be easily measured in the hard x-ray band. It can achieve a detection rate of 100 GRBs per year which ensures the scientific output of SVOM.

  5. SVOM gamma ray monitor

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The space-based multi-band astronomical Variable Object Monitor(SVOM) mission is dedicated to the detection,localization and broad-band study of gamma-ray bursts(GRBs) and other high-energy transient phenomena.The gamma ray monitor(GRM) onboard is designed to observe GRBs up to 5 MeV.With this instrument,one of the key GRB parameters,Epeak,can be easily measured in the hard X-ray band.It can achieve a detection rate of 100 GRBs per year which ensures the scientific output of SVOM.

  6. Application of On-Board Evolutionary Algorithms to Underwater Robots to Optimally Replan Missions with Energy Constraints

    Directory of Open Access Journals (Sweden)

    M. L. Seto

    2012-01-01

    Full Text Available The objective is to show that on-board mission replanning for an AUV sensor coverage mission, based on available energy, enhances mission success. Autonomous underwater vehicles (AUVs are tasked to increasingly long deployments, consequently energy management issues are timely and relevant. Energy shortages can occur if the AUV unexpectedly travels against stronger currents, is not trimmed for the local water salinity has to get back on course, and so forth. An on-board knowledge-based agent, based on a genetic algorithm, was designed and validated to replan a near-optimal AUV survey mission. It considers the measured AUV energy consumption, attitudes, speed over ground, and known response to proposed missions through on-line dynamics and control predictions. For the case studied, the replanned mission improves the survey area coverage by a factor of 2 for an energy budget, that is, a factor of 2 less than planned. The contribution is a novel on-board cognitive capability in the form of an agent that monitors the energy and intelligently replans missions based on energy considerations with evolutionary methods.

  7. 基于加速度传感器MMA8451的滑坡监测系统设计%Design of landslide monitoring system based on acceleration sensor MMA8451

    Institute of Scientific and Technical Information of China (English)

    高益; 郭峰林; 戴立

    2015-01-01

    采用MMA8451三轴速度传感器设计出一个低功耗、高精度的滑坡监测仪器。基于这款高性能传感器,ZigBee模块终端节点( TND)将位移棒测得的各方向加速度信号传递到中心节点( CND),通过PC端软件算法将加速度信号转换成对应倾角。由倾角与两个位移棒间的距离可求得该位移棒的相对偏移距离,将各相对偏移距离累加算出倾斜距离。通过实验验证表明:系统功耗小,精度高,速度快,能够很好地完成了对滑坡的监测,并且能够设定安全阀值,对山体滑坡等自然灾害进行预警。%Using MMA8451 three axis acceleration sensor to design a low power , high precision instruments of land-slide monitoring.Based on this high-performance sensor, ZigBee module terminal node (TND) passes the rod dis-placement measured inclination to the central node ( CND) , which will be accelerated into angle through PC client software algorithm .As inclination and the distance between the two displacement rods that can obtain relative dis -placement of the displacement bar , with each relative offset accumulation method finding the maximum offset .The experiment shows that:the low system power consumption , high precision , high speed , so can be well done for landslide monitoring .At the same time,the ability to set security thresholds for landslides and other natural disaster warnings is of high availability .

  8. The Anomalous Acceleration of the Pioneer Spacecrafts

    CERN Document Server

    de Diego, Jose A

    2008-01-01

    Radiometric data from the Pioneer 10 and 11 spacecrafts have revealed an unexplained constant acceleration of a_A = (8.74 +/- 1.33) x 10^(-10) m s^(-2) towards the Sun, also known as the Pioneer anomaly. Different groups have analyzed the Pioneer data and have got the same results, which rules out computer programming and handling errors. Attempts to explain this phenomenon arguing intrinsic causes on-board the spacecrafts failed or have lead to inconclusive results. Therefore, the Pioneer anomalous acceleration has motivated the interest of researchers to find out explanations that could bring insight upon the forces acting in the outer Solar Systems or a hint to discover new natural laws.

  9. 基于加速度传感器的物品运输监测系统设计%Design of Goods Transportation Monitoring System Based on Acceleration Sensor

    Institute of Scientific and Technical Information of China (English)

    赵俊涛

    2013-01-01

    本文设计了一种新型的可以对物品在运输过程中的状态和周围温湿度环境进行实时监测的系统。该系统以MMA8451加速度传感器模块和HT46RU232中央处理单元为核心,集成了GPS实时定位模块,自动评估危险程度并进行报警提示,利用上位机软件可以实现对物品状态信息的实时记录和储存,便于用户和司机对物品运输过程进行分析。经过模拟运输实验验证,该系统工作稳定可靠。%This paper puts forward a new kind of goods transportation monitoring system,which can monitor the the transport process the surrounding temperature and humidity environment of the goods in real time. The system works with MMA8451 acceleration sensor module and HT46RU232 central processing unit as the core, integrated with GPS positioning module, real-time automatic assessment of risk and alarm prompt, and using the PC software can realize real-time recording and storage of goods status information,which is convenient for the user and the driver analysis of the goods transport process. Through simulating transportation experiment, it proved that the system works stably and reliably.

  10. Review of Dose Monitoring System Calibration in BJ-6B Accelerator%BJ-6B加速器剂量监测系统校准10年回顾

    Institute of Scientific and Technical Information of China (English)

    李贤富; 谢力; 郭飞; 周进伟; 柳弥; 谭榜宪

    2013-01-01

    目的:明确按时对加速器剂量监测系统校准的必要性.方法:查阅国产BJ-6B 6Mv加速器剂量监测系统结构,以便结合电路分析剂量校准出现偏差的原因.按照IAEA提出的规程校准吸收剂量.对加速器剂量监测系统校准系数K随时间变化的情况进行回顾,选择连续的201周数据,做出校准系数和时间关系曲线.查阅维修记录,寻找系数变化大的原因.结果:系数变化大时,经过仔细排查,发现了以下比较严重的机器故障:1.电离室信号电缆因破损、漏电,校准系数由1.103变化为1.173,剂量偏低约6.3%.2.电离室击穿,输出剂量偏低约7.7%.3.防漏射铅板滑动,遮挡校准点,剂量偏低约9.9%.4.更换加速管,剂量偏低约4.7%.5.均整位置有偏移,中心轴剂量偏差7.7%.6.调制器稳压器坏,输出电压偏低,剂量偏低3.5%.较小的校准系数变化,与温度、湿度、气压等有关,有以年为周期的变化趋势.结论:元件老化,磨损,一些不容易发现的机器故障有可能影响剂量传递准确;由于加速器所处环境温度、湿度、气压等变化,也会影响加速器剂量监测系统监测准确性,一定要按国家标准GBZ126-2011规定的频次校准加速器剂量.%Objeetive:Emphasize the necessity of calibrating dose monitoring system of accelerator on time.Methods:Research the construction of dose monitoring system in BJ-6B accelerator to find the factors of dose deviation.Calibrate dose according to IAEA regulations.Review the calibration coefficient K of dose monitoring system of accelerator within the past 10 years.Draw the relation curve between calibration coefficient K and time in the past continuous 201 weeks.Look for the cause of the greater change of K by looking up the maintenance record.Results:Some serious machine trouble were found when the coefficient K change was great.1.Ionization chamber signal cable damaged,dose lower 6.3%.2.Ionization chamber broke,dose lower 7

  11. Biological quarantine on international waters: an initiative for onboard protocols

    Science.gov (United States)

    Takano, Yoshinori; Yano, Hajime; Funase, Ryu; Sekine, Yasuhito; Takai, Ken

    2012-07-01

    The research vessel Chikyu is expanding new frontiers in science, technology, and international collaboration through deep-sea expedition. The Chikyu (length: 210 m, gross tonnage: 56752 tons) has advanced and comprehensive scientific research facilities. One of the scientific purposes of the vessel is to investigate into unexplored biosphere (i.e., undescribed extremophiles) on the Earth. Therefore, "the onboard laboratory" provides us systematic microbiological protocols with a physical containment situation. In parallel, the onboard equipments provide sufficient space for fifty scientists and technical support staff. The helicopter deck also supports various logistics through transporting by a large scale helicopter (See, http://www.jamstec.go.jp/chikyu/eng/). Since the establishment of Panel on Planetary Protection (PPP) in Committee on Space Research (COSPAR), we have an international consensus about the development and promulgation of planetary protection knowledge, policy, and plans to prevent the harmful effects of biological contamination on the Earth (e.g., Rummel, 2002). However, the matter to select a candidate location of initial quarantine at BSL4 level is often problematic. To answer the key issue, we suggest that international waters can be a meaningful option with several advantages to conduct initial onboard-biological quarantine investigation. Hence, the research vessel Chikyu is promising for further PPP requirements (e.g., Enceladus sample return project: Tsou et al., 2012). Rummel, J., Seeking an international consensus in planetary protection: COSPAR's planetary protection panel. Advances in Space Research, 30, 1573-1575 (2002). Tsou, P. et al. LIFE: Life Investigation For Enceladus - A Sample Return Mission Concept in Search for Evidence of Life. Astrobiology, in press.

  12. Lunar Landing Trajectory Design for Onboard Hazard Detection and Avoidance

    Science.gov (United States)

    Paschall, Steve; Brady, Tye; Sostaric, Ron

    2009-01-01

    The Autonomous Landing and Hazard Avoidance Technology (ALHAT) Project is developing the software and hardware technology needed to support a safe and precise landing for the next generation of lunar missions. ALHAT provides this capability through terrain-relative navigation measurements to enhance global-scale precision, an onboard hazard detection system to select safe landing locations, and an Autonomous Guidance, Navigation, and Control (AGNC) capability to process these measurements and safely direct the vehicle to a landing location. This paper focuses on the key trajectory design issues relevant to providing an onboard Hazard Detection and Avoidance (HDA) capability for the lander. Hazard detection can be accomplished by the crew visually scanning the terrain through a window, a sensor system imaging the terrain, or some combination of both. For ALHAT, this hazard detection activity is provided by a sensor system, which either augments the crew s perception or entirely replaces the crew in the case of a robotic landing. Detecting hazards influences the trajectory design by requiring the proper perspective, range to the landing site, and sufficient time to view the terrain. Following this, the trajectory design must provide additional time to process this information and make a decision about where to safely land. During the final part of the HDA process, the trajectory design must provide sufficient margin to enable a hazard avoidance maneuver. In order to demonstrate the effects of these constraints on the landing trajectory, a tradespace of trajectory designs was created for the initial ALHAT Design Analysis Cycle (ALDAC-1) and each case evaluated with these HDA constraints active. The ALHAT analysis process, described in this paper, narrows down this tradespace and subsequently better defines the trajectory design needed to support onboard HDA. Future ALDACs will enhance this trajectory design by balancing these issues and others in an overall system

  13. 8 CFR 231.2 - Electronic manifest and I-94 requirement for passengers and crew onboard departing vessels and...

    Science.gov (United States)

    2010-01-01

    ... section 231 of the Act are set forth in 19 CFR 4.64 (passengers and crew members onboard vessels) and in 19 CFR 122.75a (passengers onboard aircraft) and 122.75b (crew members onboard aircraft). (b... for passengers and crew onboard departing vessels and aircraft. 231.2 Section 231.2 Aliens...

  14. 8 CFR 231.1 - Electronic manifest and I-94 requirement for passengers and crew onboard arriving vessels and...

    Science.gov (United States)

    2010-01-01

    ... section 231 of the Act are set forth in 19 CFR 4.7b (passengers and crew members onboard vessels) and in 19 CFR 122.49a (passengers onboard aircraft) and 122.49b (crew members onboard aircraft). (b... for passengers and crew onboard arriving vessels and aircraft. 231.1 Section 231.1 Aliens...

  15. Algorithms onboard the Oersted micro satellite stellar compass

    DEFF Research Database (Denmark)

    Liebe, Carl Christian; Jørgensen, John Leif

    1996-01-01

    . The technique will be described and the performance analyzed. Also, the stellar compass is more accurate than conventional star trackers, because conventional star trackers typically tracks 3-10 star in a single frame, whereas the stellar compass tracks up to 200 stars, yielding more accurate attitude estimates...... and a powerful microcomputer. The microcomputer analyses the CCD images using an onboard software star catalogue. The objective of the danish Oersted microsatellite is to measure the magnetic field of the Earth. The field is measured with a very accurate vector magnetometer. In order to utilize the accurate...

  16. Information on weather and sea conditions onboard polar cruise ships

    Directory of Open Access Journals (Sweden)

    BRÂNDUŞA CHIOTOROIU

    2016-11-01

    Full Text Available The arctic and Antarctic regions are difficult to navigate because of their severe maritime conditions. Weather forecast, forecast of the sea ice and icebergs dynamics are extremely important when planning ships routes and tourism activities including embarkation/disembarkation from boats or landing operations. New meteorological services have been created in the arctic region for broadcast purposes. The information provided by these services and received onboard ships is presented in this paper. A risk assessment should be considered for Polar Water operations such as maneuvering in ice covered waters, anchoring, shore landings etc.

  17. Calibration strategies for the LAD instrument on-board LOFT

    CERN Document Server

    Pacciani, Luigi; Argan, Andrea; Barret, Didier; Bozzo, Enrico; Feroci, Marco; Fraser, George W; Herder, Jan-Willem den; Pohl, Martin; Schmid, Christian; Tenzer, Chris; Vacchi, Andrea; Walton, Dave; Zampa, Gianluigi; Zane, Silvia

    2012-01-01

    The Scientific objectives of the LOFT mission, e.g., the study of the Neutron Star equation of state and of the Strong Gravity, require accurate energy, time and flux calibration for the 500k channels of the SDD detectors, as well as the knowledge of the detector dead-time and of the detector response with respect to the incident angle of the photons. We report here the evaluations made to asses the calibration issues for the LAD instrument. The strategies for both ground and on-board calibrations, including astrophysical observations, show that the goals are achievable within the current technologies.

  18. On-board image compression for the RAE lunar mission

    Science.gov (United States)

    Miller, W. H.; Lynch, T. J.

    1976-01-01

    The requirements, design, implementation, and flight performance of an on-board image compression system for the lunar orbiting Radio Astronomy Explorer-2 (RAE-2) spacecraft are described. The image to be compressed is a panoramic camera view of the long radio astronomy antenna booms used for gravity-gradient stabilization of the spacecraft. A compression ratio of 32 to 1 is obtained by a combination of scan line skipping and adaptive run-length coding. The compressed imagery data are convolutionally encoded for error protection. This image compression system occupies about 1000 cu cm and consumes 0.4 W.

  19. Onboard near-optimal climb-dash energy management

    Science.gov (United States)

    Weston, A.; Cliff, G.; Kelley, H.

    1985-01-01

    This paper studies optimal and near-optimal trajectories of high-performance aircraft in symmetric flight. Onboard, real-time, near-optimal guidance is considered for the climb-dash mission, using some of the boundary-layer structure and hierarchical ideas from singular perturbations. In the case of symmetric flight, this resembles neighborhood-optimal guidance using energy-to-go as the running variable. However, extension to three-dimensional flight is proposed, using families of nominal paths with heading-to-go as the additional running variable. Some computational results are presented for the symmetric case.

  20. Onboard Run-Time Goal Selection for Autonomous Operations

    Science.gov (United States)

    Rabideau, Gregg; Chien, Steve; McLaren, David

    2010-01-01

    We describe an efficient, online goal selection algorithm for use onboard spacecraft and its use for selecting goals at runtime. Our focus is on the re-planning that must be performed in a timely manner on the embedded system where computational resources are limited. In particular, our algorithm generates near optimal solutions to problems with fully specified goal requests that oversubscribe available resources but have no temporal flexibility. By using a fast, incremental algorithm, goal selection can be postponed in a "just-in-time" fashion allowing requests to be changed or added at the last minute. This enables shorter response cycles and greater autonomy for the system under control.

  1. Parallel Stirling Converters Being Developed for Spacecraft Onboard Power

    Science.gov (United States)

    Thieme, Lanny G.

    1999-01-01

    Stirling Technology Co., as part of a NASA Lewis Research Center Phase II Small Business Innovation Research contract, has successfully demonstrated paralleling two thermodynamically independent Stirling converters. A system of four Stirling converters is being developed by NASA and the Department of Energy as an alternative high-efficiency radioisotope power source for spacecraft onboard electric power for NASA deep space missions. The high Stirling efficiency, exceeding 20 percent for this application, will greatly reduce the necessary isotope inventory in comparison to the current radioisotope thermoelectric generators (RTG s), significantly reducing mission cost and risk. Stirling is the most developed converter option of the advanced power technologies under consideration.

  2. AMO EXPRESS: A Command and Control Experiment for Crew Autonomy Onboard the International Space Station

    Science.gov (United States)

    Stetson, Howard K.; Haddock, Angie T.; Frank, Jeremy; Cornelius, Randy; Wang, Lui; Garner, Larry

    2015-01-01

    NASA is investigating a range of future human spaceflight missions, including both Mars-distance and Near Earth Object (NEO) targets. Of significant importance for these missions is the balance between crew autonomy and vehicle automation. As distance from Earth results in increasing communication delays, future crews need both the capability and authority to independently make decisions. However, small crews cannot take on all functions performed by ground today, and so vehicles must be more automated to reduce the crew workload for such missions. NASA's Advanced Exploration Systems Program funded Autonomous Mission Operations (AMO) project conducted an autonomous command and control experiment on-board the International Space Station that demonstrated single action intelligent procedures for crew command and control. The target problem was to enable crew initialization of a facility class rack with power and thermal interfaces, and involving core and payload command and telemetry processing, without support from ground controllers. This autonomous operations capability is enabling in scenarios such as initialization of a medical facility to respond to a crew medical emergency, and representative of other spacecraft autonomy challenges. The experiment was conducted using the Expedite the Processing of Experiments for Space Station (EXPRESS) rack 7, which was located in the Port 2 location within the U.S Laboratory onboard the International Space Station (ISS). Activation and deactivation of this facility is time consuming and operationally intensive, requiring coordination of three flight control positions, 47 nominal steps, 57 commands, 276 telemetry checks, and coordination of multiple ISS systems (both core and payload). Utilization of Draper Laboratory's Timeliner software, deployed on-board the ISS within the Command and Control (C&C) computers and the Payload computers, allowed development of the automated procedures specific to ISS without having to certify

  3. Onboard measurement system of atmospheric carbon monoxide in the Pacific by voluntary observing ships

    Directory of Open Access Journals (Sweden)

    H. Nara

    2011-11-01

    Full Text Available Long-term monitoring of carbon monoxide (CO mixing ratios in the atmosphere over the Pacific Ocean is being carried out on commercial cargo vessels participating in the National Institute for Environmental Studies Voluntary Observing Ships program. The program provides a regular platform for measurement of atmospheric CO along four cruise routes: from Japan to Oceania, the United States, Canada, and Southeast Asia. Flask samples are collected during every cruise for subsequent analysis in the laboratory, and in 2005, continuous shipboard CO measurements were initiated on three of the routes. Here, we describe the system we developed for onboard measurement of CO mixing ratios with a commercially available gas filter correlation CO analyzer. The fully automated system measures CO in ambient air, and the detector sensitivity and background signals are calibrated by referencing the measurements to a CO-in-air standard gas (~1 ppmv and to CO-free air scrubbed with a catalyst, respectively. We examined the artificial production of CO in the high-pressure working gas standards during storage by referencing the measurements to CO standard gases maintained as our primary scale before and after use on the ships. The onboard performance of the continuous CO measurement system was evaluated by comparing its data with data from laboratory analyses of flask samples using gas chromatography with a reduction gas detector. The reasonably good consistency between the two independent measurement methods demonstrated the good performance of both methods over the course of 3–5 years. The continuous measurement system was more useful than the flask sampling method for regionally polluted air masses, which were often encountered on Southeast Asian cruises.

  4. Onboard measurement system of atmospheric carbon monoxide over the Pacific Ocean by voluntary observing ships

    Directory of Open Access Journals (Sweden)

    H. Nara

    2011-07-01

    Full Text Available Long-term monitoring of carbon monoxide (CO mixing ratios in the atmosphere over the Pacific Ocean is being carried out on commercial cargo vessels participating in the National Institute for Environmental Studies Voluntary Observing Ships program. The program provides a regular platform for measurement of atmospheric CO along four cruising routes: from Japan to Oceania, from Japan to the United States, from Japan to Canada, and from Japan to Southeast Asia. Flask samples are collected during every cruise for subsequent analysis in the laboratory, and in 2005, continuous shipboard CO measurements were initiated on three of the routes. Here, we describe the system we developed for onboard measurement of CO mixing ratios with a commercially available gas filter correlation CO analyzer. The fully automated system measures CO in ambient air, and the detector sensitivity and background signals are calibrated by referencing the measurements to a CO-in-air standard gas (~1 ppmv and to CO-free air scrubbed with a catalyst, respectively. We examined the artificial production of CO in the high-pressure working gas standards (CO balanced with purified air at ppmv levels during storage by referencing the measurements to CO standard gases maintained as our primary scale before and after use on the ships. The onboard performance of the continuous CO measurement system was evaluated by comparing its data with data from laboratory analyses of flask samples using gas chromatography with a reduction gas detector. The reasonably good consistency between the two independent measurement methods demonstrated the good performance of both methods over the course of 3–5 yr. The continuous measurement system was more useful than the flask sampling method for regionally polluted air masses, which were often encountered on Southeast Asian cruises.

  5. A fast onboard star-extraction algorithm optimized for the SVOM Visible Telescope

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The Space multi-band Variable Object Monitor(SVOM) is a proposed Chinese astronomical satellite,dedicated to the detection,localization and measurement of gamma-ray bursts(GRBs) on a cosmological scale.An efficient algorithm is developed for the purpose of onboard star extraction from the CCD images obtained with the Visible Telescope(VT) onboard the SVOM.The CCD pixel coordinates of the reference stars will be used to refine the astronomical position of the satellite,which will facilitate triggering rapid ground-based follow-up observations of the GRBs.In this algorithm,the image is divided into a number of grid cells and the "global" pixel-value maximum within each cell is taken as the first-guess position of a "bright" star.The correct center position of a star is then computed using a simple iterative method.Applying two additional strategies,i.e.,scanning the image only by even(or odd) lines or in a black-white chess board mode,we propose to further reduce the time to extract the stars.To examine the efficiency of the above algorithms,we applied them to the experimental images obtained with a ground-based telescope.We find that the accuracy of the astronomical positioning achieved by our method is comparable to that derived by using the conventional star-extraction method,while the former needs about 25 times less CPU time than the latter.This will significantly improve the performance of the SVOM VT mission.

  6. Digital signal processing techniques for on-board processing satellites

    Science.gov (United States)

    Kwan, Ching Chung

    1990-08-01

    In on-board processing satellite systems in which frequency division multiple access (FDMA)/signal channel per carrier (SCPC) access schemes are employed, transmultiplexers are required for the frequency demultiplexing of the SCPC signals. Digital techniques for the implementation of the transmultiplexer for such application were examined. The signal processing in the transmultiplexer operations involved many parameters which could be optimized in order to reduce the hardware complexity while satisfying the level of performance required of the system. An approach for the assessment of the relationship between the various parameters and the system performance was devised, which allowed hardware requirement of practical system specifications to be estimated. For systems involving signals of different bandwidths, a more flexible implementation of the transmultiplexer is required and two computationally efficient methods, the DFT convolution and analysis/synthesis filter bank, were investigated. These methods gave greater flexibility to the input frequency plan of the transmultiplexer, at the expense of increased computational requirements. Filters were then designed to exploit specific properties of the flexible transmultiplexer methods, resulting in considerable improvement in their efficiencies. Hardware implementation of the flexible transmultiplexer was considered and an efficient multiprocesser architecture in combination with parallel processing software algorithms for the signal processing operations were designed. Finally, an experimental model of the payload for a land-mobile satellite system proposal, T-SAT, was constructed using general-purpose digital signal processors and the merits of the on-board processing architecture were demonstrated.

  7. Onboard Radar Processing Development for Rapid Response Applications

    Science.gov (United States)

    Lou, Yunling; Chien, Steve; Clark, Duane; Doubleday, Josh; Muellerschoen, Ron; Wang, Charles C.

    2011-01-01

    We are developing onboard processor (OBP) technology to streamline data acquisition on-demand and explore the potential of the L-band SAR instrument onboard the proposed DESDynI mission and UAVSAR for rapid response applications. The technology would enable the observation and use of surface change data over rapidly evolving natural hazards, both as an aid to scientific understanding and to provide timely data to agencies responsible for the management and mitigation of natural disasters. We are adapting complex science algorithms for surface water extent to detect flooding, snow/water/ice classification to assist in transportation/ shipping forecasts, and repeat-pass change detection to detect disturbances. We are near completion of the development of a custom FPGA board to meet the specific memory and processing needs of L-band SAR processor algorithms and high speed interfaces to reformat and route raw radar data to/from the FPGA processor board. We have also developed a high fidelity Matlab model of the SAR processor that is modularized and parameterized for ease to prototype various SAR processor algorithms targeted for the FPGA. We will be testing the OBP and rapid response algorithms with UAVSAR data to determine the fidelity of the products.

  8. Onboard Radar Processing Development for Rapid Response Applications

    Science.gov (United States)

    Lou, Yunling; Chien, Steve; Clark, Duane; Doubleday, Josh; Muellerschoen, Ron; Wang, Charles C.

    2011-01-01

    We are developing onboard processor (OBP) technology to streamline data acquisition on-demand and explore the potential of the L-band SAR instrument onboard the proposed DESDynI mission and UAVSAR for rapid response applications. The technology would enable the observation and use of surface change data over rapidly evolving natural hazards, both as an aid to scientific understanding and to provide timely data to agencies responsible for the management and mitigation of natural disasters. We are adapting complex science algorithms for surface water extent to detect flooding, snow/water/ice classification to assist in transportation/ shipping forecasts, and repeat-pass change detection to detect disturbances. We are near completion of the development of a custom FPGA board to meet the specific memory and processing needs of L-band SAR processor algorithms and high speed interfaces to reformat and route raw radar data to/from the FPGA processor board. We have also developed a high fidelity Matlab model of the SAR processor that is modularized and parameterized for ease to prototype various SAR processor algorithms targeted for the FPGA. We will be testing the OBP and rapid response algorithms with UAVSAR data to determine the fidelity of the products.

  9. Modeling and Simulation Reliable Spacecraft On-Board Computing

    Science.gov (United States)

    Park, Nohpill

    1999-01-01

    The proposed project will investigate modeling and simulation-driven testing and fault tolerance schemes for Spacecraft On-Board Computing, thereby achieving reliable spacecraft telecommunication. A spacecraft communication system has inherent capabilities of providing multipoint and broadcast transmission, connectivity between any two distant nodes within a wide-area coverage, quick network configuration /reconfiguration, rapid allocation of space segment capacity, and distance-insensitive cost. To realize the capabilities above mentioned, both the size and cost of the ground-station terminals have to be reduced by using reliable, high-throughput, fast and cost-effective on-board computing system which has been known to be a critical contributor to the overall performance of space mission deployment. Controlled vulnerability of mission data (measured in sensitivity), improved performance (measured in throughput and delay) and fault tolerance (measured in reliability) are some of the most important features of these systems. The system should be thoroughly tested and diagnosed before employing a fault tolerance into the system. Testing and fault tolerance strategies should be driven by accurate performance models (i.e. throughput, delay, reliability and sensitivity) to find an optimal solution in terms of reliability and cost. The modeling and simulation tools will be integrated with a system architecture module, a testing module and a module for fault tolerance all of which interacting through a centered graphical user interface.

  10. Processing the data of measurements of angular velocity and microaccelerations onboard the Foton-12 satellite

    Science.gov (United States)

    Sazonov, V. V.

    2011-10-01

    The results of reconstruction of uncontrolled rotational motion of the Foton-12 satellite using the measurement data of onboard sensors are presented. This problem has already been solved successfully several years ago. The satellite motion was reconstructed using the data of measuring the Earth's magnetic field. The data of measuring the angular velocity and microaccelerations by the QSAM system were actually not used for this purpose, since these data include a clearly seen additional component whose origin was at that time unclear. This component prevented one from using these data directly for reconstruction of the angular motion. Later it became clear that the additional component was caused by the Earth's magnetic field. Discovery of this fact allowed us to make necessary corrections when processing the QSAM system data and to use them for reconstruction of rotational motion of Foton-12. Below, a modified method of processing the QSAM system data is described together with the results of its application. The main result is obtained by comparing the motion reconstructed from measurements of angular velocity or acceleration with that found by way of processing the measurements of the Earth's magnetic field. Their coincidence turned out to be rather accurate.

  11. Hypersonic wind-tunnel free-flying experiments with onboard instrumentation

    KAUST Repository

    Mudford, Neil R.

    2015-01-01

    Hypersonic wind-tunnel testing with "free-flight" models unconnected to a sting ensures that sting/wake flow interactions do not compromise aerodynamic coefficient measurements. The development of miniaturized electronics has allowed the demonstration of a variant of a new method for the acquisition of hypersonic model motion data using onboard accelerometers, gyroscopes, and a microcontroller. This method is demonstrated in a Mach 6 wind-tunnel flow, whose duration and pitot pressure are sufficient for the model to move a body length or more and turn through a significant angle. The results are compared with those obtained from video analysis of the model motion, the existing method favored for obtaining aerodynamic coefficients in similar hypersonic wind-tunnel facilities. The results from the two methods are in good agreement. The new method shows considerable promise for reliable measurement of aerodynamic coefficients, particularly because the data obtained are in more directly applicable forms of accelerations and rates of turn, rather than the model position and attitude obtained from the earlier visualization method. The ideal may be to have both methods operating together.

  12. Calculating particle spectra from the solar electron and proton telescope onboard STEREO

    Energy Technology Data Exchange (ETDEWEB)

    Gieseler, Jan; Boettcher, Stephan; Heber, Bernd; Koehler, Jan [IEAP, CAU Kiel, Kiel (Germany)

    2013-07-01

    STEREO (Solar TErrestrial RElations Observatory) was launched on October 26, 2006. It consists of two spacecraft on heliocentric orbits, one preceding the Earth, the other following it. The Solar Electron and Proton Telescope (SEPT) onboard each of the two spacecraft is made up of two dual double-ended magnetic/foil particle telescopes which separate and measure electrons (from 30 to 400 keV) and ions, mainly protons and α-particles (from 70 keV to 2.2 MeV). Low energy ions are stopped by the thin foil which electrons can pass with an essentially unaltered spectrum. The magnet on the other side deflects electrons while ions still reach the detector. Up to now, SEPT energy spectra were obtained using defined energy channels from accelerator calibration measurements and geometric factors derived from Monte Carlo simulations. We try a different approach, applying inversion methods to calculate the energy spectra from the measurements, expecting higher accuracy and better separation of the different particle populations.

  13. On-Board Particulate Filter Failure Prevention and Failure Diagnostics Using Radio Frequency Sensing

    Energy Technology Data Exchange (ETDEWEB)

    Sappok, Alex [Filter Sensing Technologies; Ragaller, Paul [Filter Sensing Technologies; Herman, Andrew [CTS Corporation; Bromberg, L. [Massachusetts Institute of Technology (MIT); Prikhodko, Vitaly Y [ORNL; Parks, II, James E [ORNL; Storey, John Morse [ORNL

    2017-01-01

    The increasing use of diesel and gasoline particulate filters requires advanced on-board diagnostics (OBD) to prevent and detect filter failures and malfunctions. Early detection of upstream (engine-out) malfunctions is paramount to preventing irreversible damage to downstream aftertreatment system components. Such early detection can mitigate the failure of the particulate filter resulting in the escape of emissions exceeding permissible limits and extend the component life. However, despite best efforts at early detection and filter failure prevention, the OBD system must also be able to detect filter failures when they occur. In this study, radio frequency (RF) sensors were used to directly monitor the particulate filter state of health for both gasoline particulate filter (GPF) and diesel particulate filter (DPF) applications. The testing included controlled engine dynamometer evaluations, which characterized soot slip from various filter failure modes, as well as on-road fleet vehicle tests. The results show a high sensitivity to detect conditions resulting in soot leakage from the particulate filter, as well as potential for direct detection of structural failures including internal cracks and melted regions within the filter media itself. Furthermore, the measurements demonstrate, for the first time, the capability to employ a direct and continuous monitor of particulate filter diagnostics to both prevent and detect potential failure conditions in the field.

  14. Using the Mil. Std 1553B data bus in future spacecraft onboard applications

    Science.gov (United States)

    Plummer, Chris; Bordes, Yves

    2002-07-01

    This paper discusses the use of the Mil. Std 1553B data bus as the principal onboard data handling bus for future spacecraft applications. The paper takes a pragmatic approach by: Identifying the characteristics of the onboard bus traffic and its characteristics; Looking at future trends in onboard bus traffic; Describing the characteristics of the Mil. Std 1553B data bus; Proposing techniques that can be used on the Mil. Std 1553B data bus in future spacecraft application.

  15. Compact Ocean Models Enable Onboard AUV Autonomy and Decentralized Adaptive Sampling

    Science.gov (United States)

    2014-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Compact Ocean Models Enable Onboard AUV Autonomy and...Models Enable Onboard AUV Autonomy and Decentralized Adaptive Sampling 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...onboard autonomy of underwater vehicles”, in Proc. AGU Ocean Science Meeting, Salt Lake City, UT. [published] ● Frolov, S., R., Kudela, J., Bellingham

  16. A Lightning Detector Onboard Austrian Nanosatellite (LiNSAT)

    Science.gov (United States)

    Jaffer, G.; Koudelka, O.; Schwingenschuh, K.; Eichelberger, H.

    2010-12-01

    This paper presents architecture of a lightning detector onboard future Austrian Lightning Nanosatellite (LiNSAT) in low-earth-orbit (LEO) and results of two terrestrial measurement campaigns to geo-locate and discriminate lightning types in presence of noise sources. The LiNSAT is proposed to be launched with three satellites constellation for the purpose of Time-of-Arrival technique. Our main scientific objective is to investigate lightning events by the observation of VHF electromagnetic signals (Sferics) and to derive the signatures of lightning. One of the important parameters is lightning flash rate, which can be used as a proxy for locating severe weather activity. Another objective is to discriminate the discharges of lightning events evaluated by the inherent features and to differentiate cloud discharges (IC; intercloud and Intracloud) from ground discharges (CG; cloud-to-ground), return strokes, leaders and transionospheric pulse pairs. The discrimination is important because the ratio of the two (IC/CG) is a good indicator of convective storm development. We conducted two measurement campaigns; one for artificial lightning produced in high voltage chamber and second natural lightning recorded at urban environment. We focus mainly on envelopes of the received time series including noisy features and narrowband carriers to extract characteristic parameters. We determined the chamber inter-walls distance by considering reflections in the first measurements. Initially the algorithm for the instruments onboard electronics has been developed and verified in Matlab and will be transformed to machine language. Next consideration is to use existing lightning data from previous French mission “DEMETER” to validate the accomplished results. The lightning detector onboard has to perform tasks like determination of pulse-width, pulse-count, pulse rise/fall time etc; we get noise possibly from narrowband carriers and artifacts from satellite itself (EMC) in

  17. A recent strong X-ray flaring activity of 1ES 1959+650 with possibly less efficient stochastic acceleration

    Science.gov (United States)

    Kapanadze, B.; Dorner, D.; Vercellone, S.; Romano, P.; Kapanadze, S.; Mdzinarishvili, T.

    2016-09-01

    We present an X-ray flaring activity of 1ES 1959+650 in 2015 August-2016 January, which was the most powerful and prolonged during the 10.75 yr period since the start of its monitoring with X-ray Telescope onboard Swift. A new highest historical 0.3-10 keV count rate was recorded three times that makes this object the third BL Lacertae source exceeding the level of 20 counts s-1. Along with the overall variability by a factor of 5.7, this epoch was characterized by fast X-ray flares by a factor of 2.0-3.1, accompanied with an extreme spectral variability. The source also shows a simultaneous flaring activity in the optical - UV and 0.3-100 GeV bands, although a fast γ-ray flare without significant optical - X-ray counterparts is also found. In contrast to the X-ray flares in the previous years, the stochastic acceleration seems be less important for the electrons responsible for producing X-ray emission during this flare that challenges the earlier suggestion that the electrons in the jets of TeV-detected BL Lacertae objects should undergo an efficient stochastic acceleration resulting in a lower X-ray spectral curvature.

  18. Comparison of the frequency estimation of the DORIS/Jason2 oscillator thanks to the onboard DIODE and Time Transfer by Laser Link experiment

    Science.gov (United States)

    Jayles, C.; Exertier, P.; Martin, N.; Chauveau, J. P.; Samain, E.; Tourain, C.; Auriol, A.; Guillemot, P.

    2016-12-01

    The main applications for DORIS are precise orbit determination, and precise Geodesy. Onboard Jason-2 for instance, the DORIS tracking component is the French contribution to the precise orbit determination capability, a key capability for altimetry product scientific result accuracy. T2L2 is a time transfer technique based on the propagation of light pulses for synchronization between two clocks. Hosting T2L2 on-board Jason-2 was to allow for very fine DORIS USO (Ultra-Stable Oscillator) frequency monitoring, and for this purpose T2L2 was connected to the DORIS USO. Thanks to the continuous tracking of T2L2/Jason-2 by the Laser Ranging network it is possible to monitor the USO for several days, weeks, and even much longer, and thus to also compare with the DIODE (the DORIS on-board orbit determination software) frequency bias estimates. The DORIS USO frequency biases estimate comparison between two independent systems, T2L2 and DIODE, can be of benefit to both, allowing the accuracies of both systems to be better understood, and for improvements to be made to both systems. Such comparison is the central topic of the present paper. T2L2 monitors the DORIS on-board USO frequency with an accuracy of much better than 10-12 which is the specification for the Doppler instrumentation. The paper investigates the limits of the DORIS-DIODE frequency bias estimates using T2L2, showing that USO frequency compliance accuracy of 10-12 has been reached.

  19. Piezoelectric particle accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Kemp, Mark A.; Jongewaard, Erik N.; Haase, Andrew A.; Franzi, Matthew

    2017-08-29

    A particle accelerator is provided that includes a piezoelectric accelerator element, where the piezoelectric accelerator element includes a hollow cylindrical shape, and an input transducer, where the input transducer is disposed to provide an input signal to the piezoelectric accelerator element, where the input signal induces a mechanical excitation of the piezoelectric accelerator element, where the mechanical excitation is capable of generating a piezoelectric electric field proximal to an axis of the cylindrical shape, where the piezoelectric accelerator is configured to accelerate a charged particle longitudinally along the axis of the cylindrical shape according to the piezoelectric electric field.

  20. On-board Payload Data Processing from Earth to Space Segment

    Science.gov (United States)

    Tragni, M.; Abbattista, C.; Amoruso, L.; Cinquepalmi, L.; Bgongiari, F.; Errico, W.

    2013-09-01

    Matching the users application requirements with the more and more huge data streaming of the satellite missions is becoming very complex. But we need both of them. To face both the data management (memory availability) and their transmission (band availability) many recent R&D activities are studying the right way to move the data processing from the ground segment to the space segment by the development of the so-called On-board Payload Data Processing (OPDP). The space designer are trying to find new strategies to increase the on board computation capacity and its viability to overcome such limitations, memory and band, focusing the transmission of remote sensing information (not only data) towards their final use. Some typical applications which can benefit of the on board payload data processing include the automatic control of a satellites constellation which can modify its scheduled acquisitions directly on-board and according to the information extracted from the just acquired data, increasing, for example, the capability of monitoring a specific objective (such as oil spills, illegal traffic) with a greater versatility than a traditional ground segment workflow. The authors and their companies can count on a sound experience in design and development of open, modular and compact on-board processing systems. Actually they are involved in a program, the Space Payload Data Processing (SpacePDP) whose main objective is to develop an hardware and a software framework able to perform both the space mission standard tasks (sensors control, mass storage devices management, uplink and downlink) and the specific tasks required by each mission. SpacePDP is an Open and modular Payload Data Processing system, composed of Hardware and Software modules included a SDK. The whole system is characterised by flexible and customizable building blocks that form the system architectures and by a very easy way to be integrated in the missions by the SDK (a development

  1. The Glast Burst Monitor

    Science.gov (United States)

    Meegan, Charles

    2000-01-01

    The Gamma-Ray Large Area Space Telescope (GLAST) will include a secondary instrument to augment the observatory's capabilities for GRB studies. The GLAST Burst Monitor (GBK is a collaboration between Marshall Space Flight Center, the University of Huntsville, Alabama, and the Max Plank Institute for Extraterrestrial Physics. The purpose of the GBM is to extend energy coverage below the main instrument's lower limit of about 20 MeV, and to provide an on-board burst trigger and approximate location. The instrument consists of twelve NaI detectors and two BGO detectors. This combination provides energy coverage from a few keV up to about 30 MeV.

  2. Use of the Operational Air Quality Monitor (AQM) for In-Flight Water Testing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Currently, the Air Quality Monitor (AQM) on-board ISS provides specific information for a number of target compounds in the air. However, there is a significant...

  3. Acceleration without Horizons

    CERN Document Server

    Doria, Alaric

    2015-01-01

    We derive the metric of an accelerating observer moving with non-constant proper acceleration in flat spacetime. With the exception of a limiting case representing a Rindler observer, there are no horizons. In our solution, observers can accelerate to any desired terminal speed $v_{\\infty} < c$. The motion of the accelerating observer is completely determined by the distance of closest approach and terminal velocity or, equivalently, by an acceleration parameter and terminal velocity.

  4. A new model for understanding teamwork onboard: the shipmate model.

    Science.gov (United States)

    Espevik, Roar; Olsen, Olav Kjellevold

    2013-01-01

    The increasing complexity onboard a ship underline the importance of crews that are able to coordinate and cooperate with each other to facilitate task objectives through a shared understanding of resources (e.g. team members' knowledge, skills and experience), the crew's goals, and the constrains under which they work. Rotation of personnel through 24/7 shift-work schedules and replacements often put crews ina position of having little or no previous history as a team. Findings from 3 studies indicated that unfamiliar teams used less efficient coordination strategies which reduced efficiency and increased levels of stress in situations where team members where experts on task, distributed or unknown to task and environment.Implications for staffing, safety and training are discussed.

  5. TSP-Based Generic Payload On-Board Software

    Science.gov (United States)

    Arberet, P.; Metge, J.-J.; Gras, O.; Crespo, A.

    2009-05-01

    The paper address the contect and rationale for deciding to develop a TSP-based solution for payload on-board software, highly generic and reusable, project named LVCUGEN. Then it describes the key design issues and the associated architectual achievements obtained at the end of development phase of LVCUGEN. It provides some inputs on the way to instantiate the developed framework in the scope of deployment of the solution on a target-project. Last, the paper presents the status of the project and the forthcoming activities, also open issues, still to be performed. Some perspectives are provided in particular the selection of the first space program targeted for deployment of the solution.

  6. Novel satellite transport protocol with on-board spoofing proxy

    Institute of Scientific and Technical Information of China (English)

    Liu Jiong; Cao Zhigang; Wang Jinglin

    2006-01-01

    As a result of the exponential growing rate of worldwide Internet usage, satellite systems are required to support broadband Internet applications. The transmission control protocol (TCP) which is widely used in the Internet, performs very well on wired networks. However, in the case of satellite channels, due to the delay and transmission errors, TCP performance degrades significantly and bandwidth of satellite links can not be fully utilized. To improve the TCP performance, a new idea of placing a TCP spoofing proxy in the satellite is considered. A Novel Satellite Transport Protocol (NSTP) which takes advantage of the special properties of the satellite channel is also proposed. By using simulation, as compared with traditional TCPs, the on-board spoofing proxy integrated with the special transport protocol can significantly enhance throughput performance on the high BER satellite link, the time needed to transfer files and the bandwidth used in reverse path are sharply reduced.

  7. DAMPE silicon tracker on-board data compression algorithm

    CERN Document Server

    Dong, Yifan; Qiao, Rui; Peng, Wenxi; Fan, Ruirui; Gong, Ke; Wu, Di; Wang, Huanyu

    2015-01-01

    The Dark Matter Particle Explorer (DAMPE) is an upcoming scientific satellite mission for high energy gamma-ray, electron and cosmic rays detection. The silicon tracker (STK) is a sub detector of the DAMPE payload with an excellent position resolution (readout pitch of 242um), which measures the incident direction of particles, as well as charge. The STK consists 12 layers of Silicon Micro-strip Detector (SMD), equivalent to a total silicon area of 6.5m$^2$. The total readout channels of the STK are 73728, which leads to a huge amount of raw data to be dealt. In this paper, we focus on the on-board data compression algorithm and procedure in the STK, which was initially verified by cosmic-ray measurements.

  8. Safe Onboard Guidance and Control Under Probabilistic Uncertainty

    Science.gov (United States)

    Blackmore, Lars James

    2011-01-01

    An algorithm was developed that determines the fuel-optimal spacecraft guidance trajectory that takes into account uncertainty, in order to guarantee that mission safety constraints are satisfied with the required probability. The algorithm uses convex optimization to solve for the optimal trajectory. Convex optimization is amenable to onboard solution due to its excellent convergence properties. The algorithm is novel because, unlike prior approaches, it does not require time-consuming evaluation of multivariate probability densities. Instead, it uses a new mathematical bounding approach to ensure that probability constraints are satisfied, and it is shown that the resulting optimization is convex. Empirical results show that the approach is many orders of magnitude less conservative than existing set conversion techniques, for a small penalty in computation time.

  9. Dual-wavelength laser source for onboard atom interferometry.

    Science.gov (United States)

    Ménoret, V; Geiger, R; Stern, G; Zahzam, N; Battelier, B; Bresson, A; Landragin, A; Bouyer, P

    2011-11-01

    We present a compact and stable dual-wavelength laser source for onboard atom interferometry with two different atomic species. It is based on frequency-doubled telecom lasers locked on a femtosecond optical frequency comb. We take advantage of the maturity of fiber telecom technology to reduce the number of free-space optical components, which are intrinsically less stable, and to make the setup immune to vibrations and thermal fluctuations. The source provides the frequency agility and phase stability required for atom interferometry and can easily be adapted to other cold atom experiments. We have shown its robustness by achieving the first dual-species K-Rb magneto-optical trap in microgravity during parabolic flights.

  10. Efficient Spectral Endmember Detection Onboard the EO-1 Spacecraft

    Science.gov (United States)

    Bornstein, Ben; Thompson, David R.; Tran, Daniel; Bue, Brian; Chien, Steve; Castano, Rebecca

    2011-01-01

    Spaceflight and planetary exploration place severe constraints on the available bandwidth for downlinking large hyperspectral images. In addition, communications with spacecraft often occur intermittently, so mission-relevant hyperspectral data must wait for analysis on the ground before it can inform spacecraft activity planning. Onboard endmember detection can help alleviate these problems. It enables novelty detection and target identification for scheduling follow-up activities such as additional observation by narrow field of view instruments. Additionally, endmember analysis can facilitate data summary for downlink. This work describes a planned experiment of selective downlink by the EO-1 autonomous spacecraft. Here an efficient superpixel endmember detection algorithm keeps to the limited computational constraints of the flight processor. Tests suggest the procedure could enable significant improvements in downlink efficiency.

  11. Onboard Algorithms for Data Prioritization and Summarization of Aerial Imagery

    Science.gov (United States)

    Chien, Steve A.; Hayden, David; Thompson, David R.; Castano, Rebecca

    2013-01-01

    Many current and future NASA missions are capable of collecting enormous amounts of data, of which only a small portion can be transmitted to Earth. Communications are limited due to distance, visibility constraints, and competing mission downlinks. Long missions and high-resolution, multispectral imaging devices easily produce data exceeding the available bandwidth. To address this situation computationally efficient algorithms were developed for analyzing science imagery onboard the spacecraft. These algorithms autonomously cluster the data into classes of similar imagery, enabling selective downlink of representatives of each class, and a map classifying the terrain imaged rather than the full dataset, reducing the volume of the downlinked data. A range of approaches was examined, including k-means clustering using image features based on color, texture, temporal, and spatial arrangement

  12. Dual-wavelength laser source for onboard atom interferometry

    CERN Document Server

    Ménoret, Vincent; Stern, Guillaume; Zahzam, Nassim; Battelier, Baptiste; Bresson, Alexandre; Landragin, Arnaud; Bouyer, Philippe

    2011-01-01

    We present a compact and stable dual-wavelength laser source for onboard atom interferometry with two different atomic species. It is based on frequency-doubled telecom lasers locked on a femtosecond optical frequency comb. We take advantage of the maturity of fiber telecom technology to reduce the number of free-space optical components which are intrinsically less stable, and to make the setup immune to vibrations and thermal fluctuations. The source provides the frequency agility and phase stability required for atom interferometry and can easily be adapted to other cold atom experiments. We have shown its robustness by achieving the first dual-species K-Rb magneto optical trap in microgravity during parabolic flights.

  13. An Efficient Photo Voltaic System for Onboard Ship Applications

    Directory of Open Access Journals (Sweden)

    Shashidhar Kasthala

    2016-02-01

    Full Text Available In this paper a high efficient photovoltaic system is proposed for onboard ship applications which convert the lower voltage obtained from solar modules to higher voltage required by the ship service loads. In a typical photovoltaic system only step-up /boost converter is used due to which the converter has to operate in extreme duty ratio, resulting in increase of switching losses and thus decreasing the overall efficiency. But in this paper the conventional boost converter is used with interleaved inductors and capacitors. The poposed system stores the energy in inductors and thus reduces the stress in the switches (Without allowing the total voltage to appear across the switch. The simulation is designed using MATLAB/Simulink with an Input voltage of 40-V to achieve a output voltage of 300-380 V. The developed simulation results are compared for output powers of 500W and 1kW

  14. Smart Onboard Inspection of High Pressure Gas Fuel Cylinders

    Energy Technology Data Exchange (ETDEWEB)

    Beshears, D.L.; Starbuck, J.M.

    1999-09-27

    The use of natural gas as an alternative fuel in automotive applications is not widespread primarily because of the high cost and durability of the composite storage tanks. Tanks manufactured using carbon fiber are desirable in weight critical passenger vehicles because of the low density of carbon fiber. The high strength of carbon fiber also translates to a weight reduction because thinner wall designs are possible to withstand the internal pressure loads. However, carbon fiber composites are prone to impact damage that over the life of the storage tank may lead to an unsafe condition for the vehicle operator. A technique that potentially may be a reliable indication of developing hazardous conditions in composite fuel tanks is imbedded fiber optics. The applicability of this technique to onboard inspection is discussed and results from preliminary lab testing indicate that fiber optic sensors can reliably detect impact damage.

  15. Onboard Catalysis of Formic Acid for Hydrogen Fueled Vehicles

    Science.gov (United States)

    Karim, Altaf; Mamoor, Muhammad

    2015-03-01

    Metal hydrides are used as a medium of hydrogen storage in hydrogen powered vehicles. Such hydride materials cannot store hydrogen more than 10 wt%. The bottleneck in this issue is the reversible storage of hydrogen at ambient temperature and pressure. Alternatively formic acid is becoming more popular medium for the onboard hydrogen production for these vehicles. Its decomposition on metal surfaces and nanostructures is considered to be a potential method to produce CO-free hydrogen at near ambient temperatures. We applied Density Functional Theory (DFT) based Kinetic Monte Carlo (KMC) simulations as our tool to study the reaction kinetics of hydrogen production from formic acid on different catalytic surfaces and nano structures (Au, Pd, Rh, Pt). Our results show that nanostructures and artificially engineered bimetallic catalysts give higher rate of hydrogen production then their monometallic counter parts under various temperature and pressure conditions.

  16. Advanced on-board electric vehicle charger. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-12-31

    The design and development of an on-board charger power module for use in electric vehicles is described. The module operates at 20KHz in a series resonant, half bridge configuration. Circuit design trade-offs, module performance, and solutions to the problems of acoustic noise, maintaining high power factor, circuit protection and operating reliability are discussed. The power module operates from a single phase, 240 V, 50/60 Hz utility line. Average power factor is 0.90; efficiency at maximum power output is 86%. The module is rated to charge a bank consisting of 20 Exide EV-106 batteries (60 cells) to an end voltage of 2.42 V/cell. Physically, the module weighs less than 17 Kg. Projected manufacturing cost at the thousand unit level is $394.00 (1978 dollars).

  17. Optical Observations Of Fermi LAT Monitored Blazars

    Science.gov (United States)

    Cook, Kyle; Carini, M. T.

    2009-01-01

    For the past 8 years the Bell Observatory at Western Kentucky University has been conducting R band monitoring of the variability of approximately 50 Blazars. A subset of these objects are being routinely observed with the LAT instrument on-board the Fermi Space Telescope. Adding the Robotically Controlled Telescope (RCT) at Kitt Peak National Observatory and observations with the AZT-11 telescope at the Crimean Astrophysical Observatory (CRAO), we are intensively monitoring the Blazars on the Lat monitoring list. We present the results of our long term monitoring of the LAT monitored Blazars, as well as the recent contemporaneous optical R band observations we have obtained of the LAT Blazars.

  18. Summary of observations of the infrared camera (IRC) onboard AKARI

    Science.gov (United States)

    Onaka, T.; Matsuhara, H.; Wada, T.; Ishihara, D.; Ohyama, Y.; Sakon, I.; Shimonishi, T.; Ohsawa, R.; Mori, T. I.; Egusa, F.; Usui, F.; Takita, S.; Murakami, H.; Oyabu, S.; Yamagishi, M.; Mori, T.; Mouri, A.; Kondo, T.; Suzuki, S.; Kaneda, H.; Ita, Y.; Ootsubo, T.

    2012-09-01

    AKARI, the Japanese satellite mission dedicated to infrared astronomy was launched in 2006 February and exhausted its liquid helium in 2007 August. During the cold mission phase, the Infrared Camera (IRC) onboard carried out an all-sky survey at 9 and 18µm with better spatial resolution and higher sensitivity than IRAS. Both bands also have slightly shorter wavelength coverage than IRAS 12 and 25μm bands and thus provide different information on the infrared sky. All-sky image data of the IRC are now in the final processing and will be released to the public within a year. After the exhaustion of the cryogen, the telescope and focal plane instruments of AKARI had still been kept at sufficiently low temperatures owing to the onboard cryocooler. Near-infrared (NIR) imaging and spectroscopic observations with the IRC had continued until 2011 May, when the spacecraft had a serious problem in the power supply system that forced us to terminate the observation. The IRC carried out nearly 20000 pointing observations in total despite of its near-earth orbit. About a half of them were performed after the exhaustion of the cryogen in the spectroscopic modes, which provided high-sensitivity NIR spectra from 2 to 5µm without disturbance of the terrestrial atmosphere. During the warm mission phase, the temperature of the instrument gradually increased and changed the array operation conditions. We present a summary of AKARI/IRC observations, including the all-sky mid-infrared diffuse data as well as the data taken in the warm mission phase.

  19. Advanced stellar compass onboard autonomous orbit determination, preliminary performance.

    Science.gov (United States)

    Betto, Maurizio; Jørgensen, John L; Jørgensen, Peter S; Denver, Troelz

    2004-05-01

    Deep space exploration is in the agenda of the major space agencies worldwide; certainly the European Space Agency (SMART Program) and the American NASA (New Millennium Program) have set up programs to allow the development and the demonstration of technologies that can reduce the risks and the cost of deep space missions. From past experience, it appears that navigation is the Achilles heel of deep space missions. Performed on ground, this imposes considerable constraints on the entire system and limits operations. This makes it is very expensive to execute, especially when the mission lasts several years and, furthermore, it is not failure tolerant. Nevertheless, to date, ground navigation has been the only viable solution. The technology breakthrough of advanced star trackers, like the advanced stellar compass (ASC), might change this situation. Indeed, exploiting the capabilities of this instrument, the authors have devised a method to determine the orbit of a spacecraft autonomously, onboard, and without a priori knowledge of any kind. The solution is robust and fast. This paper presents the preliminary performance obtained during the ground testing in August 2002 at the Mauna Kea Observatories. The main goals were: (1) to assess the robustness of the method in solving autonomously, onboard, the position lost-in-space problem; (2) to assess the preliminary accuracy achievable with a single planet and a single observation; (3) to verify the autonomous navigation (AutoNav) module could be implemented into an ASC without degrading the attitude measurements; and (4) to identify the areas of development and consolidation. The results obtained are very encouraging.

  20. Accelerating flight: Edge with arbitrary acceleration

    CSIR Research Space (South Africa)

    Gledhill, Irvy MA

    2011-11-01

    Full Text Available ? temporal scales ? Euler ? convection ? Reynolds ? translational viscous ? Ekman ? rotational viscous ? Translational acceleration ? related to g ? Rotational accleration ? Rossby ? Coriolis ? Centrifugal ? Gravitational ? CSIR 2009...

  1. Classifying sows' activity types from acceleration patterns

    DEFF Research Database (Denmark)

    Cornou, Cecile; Lundbye-Christensen, Søren

    2008-01-01

    -dimensional axes, plus the length of the acceleration vector) are selected for each activity. Each time series is modeled using a Dynamic Linear Model with cyclic components. The classification method, based on a Multi-Process Kalman Filter (MPKF), is applied to a total of 15 times series of 120 observations......An automated method of classifying sow activity using acceleration measurements would allow the individual sow's behavior to be monitored throughout the reproductive cycle; applications for detecting behaviors characteristic of estrus and farrowing or to monitor illness and welfare can be foreseen....... This article suggests a method of classifying five types of activity exhibited by group-housed sows. The method involves the measurement of acceleration in three dimensions. The five activities are: feeding, walking, rooting, lying laterally and lying sternally. Four time series of acceleration (the three...

  2. WE-AB-303-09: Rapid Projection Computations for On-Board Digital Tomosynthesis in Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Iliopoulos, AS; Sun, X [Duke University, Durham, NC (United States); Pitsianis, N [Aristotle University of Thessaloniki (Greece); Duke University, Durham, NC (United States); Yin, FF; Ren, L [Duke University Medical Center, Durham, NC (United States)

    2015-06-15

    Purpose: To facilitate fast and accurate iterative volumetric image reconstruction from limited-angle on-board projections. Methods: Intrafraction motion hinders the clinical applicability of modern radiotherapy techniques, such as lung stereotactic body radiation therapy (SBRT). The LIVE system may impact clinical practice by recovering volumetric information via Digital Tomosynthesis (DTS), thus entailing low time and radiation dose for image acquisition during treatment. The DTS is estimated as a deformation of prior CT via iterative registration with on-board images; this shifts the challenge to the computational domain, owing largely to repeated projection computations across iterations. We address this issue by composing efficient digital projection operators from their constituent parts. This allows us to separate the static (projection geometry) and dynamic (volume/image data) parts of projection operations by means of pre-computations, enabling fast on-board processing, while also relaxing constraints on underlying numerical models (e.g. regridding interpolation kernels). Further decoupling the projectors into simpler ones ensures the incurred memory overhead remains low, within the capacity of a single GPU. These operators depend only on the treatment plan and may be reused across iterations and patients. The dynamic processing load is kept to a minimum and maps well to the GPU computational model. Results: We have integrated efficient, pre-computable modules for volumetric ray-casting and FDK-based back-projection with the LIVE processing pipeline. Our results show a 60x acceleration of the DTS computations, compared to the previous version, using a single GPU; presently, reconstruction is attained within a couple of minutes. The present implementation allows for significant flexibility in terms of the numerical and operational projection model; we are investigating the benefit of further optimizations and accurate digital projection sub

  3. Loads Monitoring and Hums

    Science.gov (United States)

    2001-03-01

    Strain Measurement Fibre Optic Strain Temperature Pressure Crack Gage Crack Growth Accelerometer C.G. or Local Acceleration, Vibration, Buffet Pressure...Fig. 3.3-3 Zone 4 sensor location and results 1-15 A different method of monitoring structural health is shown in Fig. 3.3-4, a fibre optic array...Computer System Fig. 3.3-4 Fibre Optic monitoring array embedded in structure The two major tasks of structural health monitoring: Identification of

  4. An air quality assessment onboard an Oberon class submarine : HMCS Okanagan

    Energy Technology Data Exchange (ETDEWEB)

    Severs, Y.D.; Sabiston, B.H.

    2000-09-01

    The Defence and Civil Institute of Environmental Medicine (DCIEM) re-examined the air quality on an Oberon class submarine, the HMCS Okanagan, to determine if the atmosphere complied with Air Purification Standard BR 1326. The main objective of the assessment was to help in the development of future submarine air quality management. The information obtained from the Oberon class submarine could be readily applied to the Victoria class submarines. The assessment involved a trial aboard an Oberon under patrol conditions. The functional and detection capabilities of analytical air monitoring instruments were assessed for a 24-hour period to obtain data regarding the contaminants onboard the submarine. A profile of carbon dioxide accumulation and oxygen consumption was determined. This was followed by an assessment of the effectiveness of air purification such as carbon dioxide scrubbing, oxygen generation and snorting. Carbon monoxide was also monitored and carboxyhemoglobin was measured in both smokers and non-smokers. In order to determine if the sanitary or electrical systems, or engine exhaust posed any danger, ammonia, ozone and nitrous compounds were also measured. In addition, hydrogen, arsine and stibene were monitored to determine any possible danger from charging batteries. The health risks associated with aerosolized particles from cooking, smoking and exhaust gases were also measured. Results showed that all contaminants were within allowable limits. However, the study also confirmed that air purification measures on diesel submarines are minimal and poorly placed and that there is a lack of exhaust ventilation. Poor air exchange was worsened by compartmentalization and blackout curtains. Several recommendations were proposed to improve the management of air quality in Victoria class submarines. 18 refs., 2 tabs., 5 figs.

  5. Design of monitoring and early warning system for roller coaster based on acceleration signal%基于加速度信号的过山车监测预警系统设计

    Institute of Scientific and Technical Information of China (English)

    李根; 朱玉田; 谢波

    2012-01-01

    Based on the requirements of special equipment safety and the current status of recreation facilities test system,a safety monitoring and early warning system for roller coaster is designed. The signal acquisition device of the system is set on the roller coaster. Digital signal processor( DSP) is used as the main control chip for its high calculation speed. Low-power consumption chips with 3. 3 V are used on the acquisition for their energy conservation and environment protection. High-frequency vibration acceleration and low-frequency motion acceleration signals are acquired in real time, and datas are transmitted to upper machine by WiFi. By using LabVlEW,the software of upper machine is developed. Wavelet analysis is applied to process the data. BP neural network is applied for fault diagnosis. Meanwhile, FFT analysis is used to process the acquired signal and standard signal and draw frequency spectrogram to check on the result of the fault diagnosis. If any fault is diagnosed, the system will sound the alarm and send out the early warning information to the relevant staff by GPRS. The experimental result shows that the system is quick, accurate and reliable.%鉴于国家对特种设备安全的要求和大型游乐设施测试系统的现状,设计了一种过山车监测预警系统.系统的信号采集装置安装在过山车上,采用数字信号处理器(DSP)作为主控芯片,运算速度快,可实现数据的实时采集,硬件电路多采用3.3V的低功耗芯片,节能环保.系统采集高频振动加速度和低频运动加速度信号,通过WiFi将数据传输给上位机,上位机软件使用LabVIEW开发,运用小波分析处理数据,并采用BP神经网络算法诊断故障,同时,对采集的信号和标准信号进行快速傅立叶变换(FFT)分析并作频谱图,可直观的检验诊断结果.如果诊断出故障,系统可发出警报并通过通用分组无线业务(GPRS)通知相关工作人员.实验结果表明:系统的运算速度快,诊断结果可靠.

  6. THE TECHNIQUE OF ANALYSIS OF SOFTWARE OF ON-BOARD COMPUTERS OF AIR VESSEL TO ABSENCE OF UNDECLARED CAPABILITIES BY SIGNATURE-HEURISTIC WAY

    Directory of Open Access Journals (Sweden)

    Viktor Ivanovich Petrov

    2017-01-01

    Full Text Available The article considers the issues of civil aviation aircraft onboard computers data safety. Infor- mation security undeclared capabilities stand for technical equipment or software possibilities, which are not mentioned in the documentation. Documentation and tests content requirements are imposed during the software certification. Documentation requirements include documents composition and content of control (specification, description and program code, the source code. Test requirements include: static analysis of program codes (including the compliance of the sources with their loading modules monitoring; dynamic analysis of source code (including implementation of routes monitor- ing. Currently, there are no complex measures for checking onboard computer software. There are no rules and regulations that can allow controlling foreign production aircraft software, and the actual receiving of software is difficult. Consequently, the author suggests developing the basics of aviation rules and regulations, which allow to analyze the programs of CA aircraft onboard computers. If there are no software source codes the two approaches of code analysis are used: a structural static and dy- namic analysis of the source code; signature-heuristic analysis of potentially dangerous operations. Static analysis determines the behavior of the program by reading the program code (without running the program which is represented in the assembler language - disassembly listing. Program tracing is performed by the dynamic analysis. The analysis of aircraft software ability to detect undeclared capa- bilities using the interactive disassembler was considered in this article.

  7. Autonomous Defensive Space Control via On-Board Artificial Neural Networks

    Science.gov (United States)

    2007-04-01

    AUTONOMOUS DEFENSIVE SPACE CONTROL VIA ON-BOARD ARTIFICIAL NEURAL NETWORKS Michael T. Manor, Major, USAF April 2007...TITLE AND SUBTITLE Sutonomous Defensive Space Control via On-Board Artificial Neural Networks 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...11 HOW ARTIFICIAL NEURAL NETWORKS WORK

  8. Reliability analysis and design of on-board computer system for small stereo mapping satellite

    Institute of Scientific and Technical Information of China (English)

    马秀娟; 曹喜滨; 马兴瑞

    2002-01-01

    The on-board computer system for a small satellite is required to be high in reliability, light in weight, small in volume and low in power consumption. This paper describes the on-board computer system with the advantages of both centralized and distributed systems, analyzes its reliability, and briefs the key techniques used to improve its reliability.

  9. Onboard Supervisor for the Ørsted Satellite Attitude Control System

    DEFF Research Database (Denmark)

    Bøgh, S.A.; Izadi-Zamanabadi, Roozbeh; Blanke, M.

    1995-01-01

    The increasing operational requirements for onboard autonomy in satellite control systems necessitates structural methods that support the design of a complete and reliable supervisory system.......The increasing operational requirements for onboard autonomy in satellite control systems necessitates structural methods that support the design of a complete and reliable supervisory system....

  10. 49 CFR 1546.202 - Persons and property onboard the aircraft.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Persons and property onboard the aircraft. 1546.202 Section 1546.202 Transportation Other Regulations Relating to Transportation (Continued... CARRIER SECURITY Operations § 1546.202 Persons and property onboard the aircraft. Each foreign air...

  11. 49 CFR 1544.202 - Persons and property onboard an all-cargo aircraft.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Persons and property onboard an all-cargo aircraft. 1544.202 Section 1544.202 Transportation Other Regulations Relating to Transportation (Continued... SECURITY: AIR CARRIERS AND COMMERCIAL OPERATORS Operations § 1544.202 Persons and property onboard an...

  12. Onboarding Experiences: An Examination of Early Institutional Advancement Professionals' Decisions

    Science.gov (United States)

    Radosh, Meghan E.

    2013-01-01

    Onboarding is a new employee orientation process that is designed to formalize and socialize new hires to an organization, or in this case higher education institutions. The onboarding experience that many new employees have can shape employee views and first impressions of their new employer, and shape their early career path to stay or leave…

  13. 2014 CERN Accelerator Schools: Plasma Wake Acceleration

    CERN Multimedia

    2014-01-01

    A specialised school on Plasma Wake Acceleration will be held at CERN, Switzerland from 23-29 November, 2014.   This course will be of interest to staff and students in accelerator laboratories, university departments and companies working in or having an interest in the field of new acceleration techniques. Following introductory lectures on plasma and laser physics, the course will cover the different components of a plasma wake accelerator and plasma beam systems. An overview of the experimental studies, diagnostic tools and state of the art wake acceleration facilities, both present and planned, will complement the theoretical part. Topical seminars and a visit of CERN will complete the programme. Further information can be found at: http://cas.web.cern.ch/cas/PlasmaWake2014/CERN-advert.html http://indico.cern.ch/event/285444/

  14. Beam-commissioning study of high-intensity accelerators using virtual accelerator model

    Science.gov (United States)

    Harada, H.; Shigaki, K.; Irie, Y.; Noda, F.; Hotchi, H.; Saha, P. K.; Shobuda, Y.; Sako, H.; Furukawa, K.; Machida, S.

    2009-04-01

    In order to control large-scale accelerators efficiently, a control system with a virtual accelerator model was constructed. The virtual accelerator (VA) is an on-line beam simulator provided with a beam monitor scheme. The VA is based upon the Experimental Physics and Industrial Control System (EPICS) and is configured under the EPICS input/output controller (IOC) in parallel with a real accelerator (RA). Thus, the machine operator can access the parameters of the RA through the channel access client and then feed them to the VA, and vice versa. Such a control scheme facilitates developments of the commissioning tools, feasibility study of the proposed accelerator parameters and examination of the measured accelerator data. This paper describes the beam commissioning results and activities by using the VA at the J-PARC 3-GeV rapid-cycling synchrotron (RCS).

  15. Beam-commissioning study of high-intensity accelerators using virtual accelerator model

    Energy Technology Data Exchange (ETDEWEB)

    Harada, H. [Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima-shi, Hiroshima 739-8526 (Japan)], E-mail: harada@hepl.hiroshima-u.ac.jp; Shigaki, K. [Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima-shi, Hiroshima 739-8526 (Japan); Irie, Y. [Accelerator Laboratory, High Energy Accelerator Research Organization (KEK), Tsukuba-shi, Ibaraki 305-0801 (Japan); Noda, F. [Energy and Environmental Systems Laboratory, Hitachi, Ltd, 7-2-1 Omika-cho, Hitachi-shi, Ibaraki 319-1221 (Japan); Hotchi, H.; Saha, P.K.; Shobuda, Y.; Sako, H. [Japan Proton Accelerator Research Complex, 2-4 Shirane Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Furukawa, K. [Accelerator Laboratory, High Energy Accelerator Research Organization (KEK), Tsukuba-shi, Ibaraki 305-0801 (Japan); Machida, S. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11, 0QX (United Kingdom)

    2009-04-21

    In order to control large-scale accelerators efficiently, a control system with a virtual accelerator model was constructed. The virtual accelerator (VA) is an on-line beam simulator provided with a beam monitor scheme. The VA is based upon the Experimental Physics and Industrial Control System (EPICS) and is configured under the EPICS input/output controller (IOC) in parallel with a real accelerator (RA). Thus, the machine operator can access the parameters of the RA through the channel access client and then feed them to the VA, and vice versa. Such a control scheme facilitates developments of the commissioning tools, feasibility study of the proposed accelerator parameters and examination of the measured accelerator data. This paper describes the beam commissioning results and activities by using the VA at the J-PARC 3-GeV rapid-cycling synchrotron (RCS)

  16. Dynamic Data-Driven Prognostics and Condition Monitoring of On-board Electronics

    Science.gov (United States)

    2012-08-27

    Completion Date(f-2): 1 a. 1 b. University of Maryland 3181 Glen L Martin Hall College Park MD 20742 Collaborated with QSI in developing STSA algorithms and...12) 209-212 m sp fl pt Baro altimeter bias 1-sigma 213-216 m sp fl pt Baro altimeter scale factor 1-sigma 217-220 ppm sp fl pt Qualtech Systems, Inc

  17. Real-Time Novel Holographic Monitoring of Airborne Trace Contaminants Onboard Space Vessels Project

    Data.gov (United States)

    National Aeronautics and Space Administration — New challenges and mission requirements constantly emerge, establishing the need for versatile equipment and instruments to perform the new/expanded tasks....

  18. In Orbit Performance of the MAXI/SSC onboard the ISS

    CERN Document Server

    Tsunemi, Hiroshi; Katayama, Haruyoshi; Kimura, Masashi; Daikyuji, Arata; Miyaguchi, Kazuhisa; Maeda, Kentaro

    2011-01-01

    We report here the in orbit performance of the CCD camera (MAXI/SSC) onboard the International Space Station (ISS). It was commissioned in August, 2009. This is the first all-sky survey mission employing X-ray CCDs. It consists of 32 CCDs each of which is 1 inch square. It is a slit camera with a field of view of 1deg.5x 90deg and scans the sky as the rotation of the ISS. The CCD on the SSC is cooled down to the working temperature around -60degC by the combination of the peltier cooler, a loop heat pipe and a radiator. The standard observation mode of the CCD is in a parallel sum mode (64-binning). The CCD functions properly although it suffers an edge glow when the Sun is near the field of view (FOV) which reduces the observation efficiency of the SSC down to about 30%. The performance of the CCD is continuously monitored both by the Mn-K X-rays and by the Cu-K X-rays. There are many sources detected, not only point sources but extended sources. Due to the lack of the effective observation time, we need mor...

  19. Solar Spectral Irradiance at 782 nm as Measured by the SES Sensor Onboard Picard

    Science.gov (United States)

    Meftah, M.; Hauchecorne, A.; Irbah, A.; Cessateur, G.; Bekki, S.; Damé, L.; Bolsée, D.; Pereira, N.

    2016-04-01

    Picard is a satellite dedicated to the simultaneous measurement of the total and solar spectral irradiance, the solar diameter, the solar shape, and to the Sun's interior through the methods of helioseismology. The satellite was launched on June 15, 2010, and pursued its data acquisitions until March 2014. A Sun Ecartometry Sensor (SES) was developed to provide the stringent pointing requirements of the satellite. The SES sensor produced an image of the Sun at 782 ± 2.5 nm. From the SES data, we obtained a new time series of the solar spectral irradiance at 782 nm from 2010 to 2014. During this period of Solar Cycle 24, the amplitude of the changes has been of the order of ± 0.08 %, corresponding to a range of about 2× 10^{-3} W m^{-2} nm^{-1}. SES observations provided a qualitatively consistent evolution of the solar spectral irradiance variability at 782 nm. SES data show similar amplitude variations with the semi-empirical model Spectral And Total Irradiance REconstruction for the Satellite era (SATIRE-S), whereas the Spectral Irradiance Monitor instrument (SIM) onboard the SOlar Radiation and Climate Experiment satellite (SORCE) highlights higher amplitudes.

  20. The High Energy cosmic-Radiation Detection (HERD) Facility onboard China's Future Space Station

    CERN Document Server

    Zhang, S N

    2014-01-01

    The High Energy cosmic-Radiation Detection (HERD) facility is one of several space astronomy payloads of the cosmic lighthouse program onboard China's Space Station, which is planned for operation starting around 2020 for about 10 years. The main scientific objectives of HERD are indirect dark matter search, precise cosmic ray spectrum and composition measurements up to the knee energy, and high energy gamma-ray monitoring and survey. HERD is composed of a 3-D cubic calorimeter (CALO) surrounded by microstrip silicon trackers (STKs) from five sides except the bottom. CALO is made of about 10$^4$ cubes of LYSO crystals, corresponding to about 55 radiation lengths and 3 nuclear interaction lengths, respectively. The top STK microstrips of seven X-Y layers are sandwiched with tungsten converters to make precise directional measurements of incoming electrons and gamma-rays. In the baseline design, each of the four side SKTs is made of only three layers microstrips. All STKs will also be used for measuring the cha...

  1. The ECLAIRs GRB-trigger telescope on-board the future mission SVOM

    CERN Document Server

    Schanne, Stéphane; Atteia, Jean-Luc; Godet, Olivier; Lachaud, Cyril; Mercier, Karine

    2015-01-01

    The Space-based multi-band astronomical Variable Objects Monitor (SVOM) is an approved satellite mission for Gamma-Ray Burst (GRB) studies, developed in cooperation between the Chinese National Space Agency (CNSA), the Chinese Academy of Sciences (CAS), the French Space Agency (CNES) and French laboratories. SVOM entered Phase B in 2014 and is scheduled for launch in 2021. SVOM will provide fast and accurate GRB localizations, and determine the temporal and spectral properties of the GRB emission, thanks to a set of 4 on-board instruments. The trigger system of the coded-mask telescope ECLAIRs images the sky in the 4-120 keV energy range, in order to detect and localize GRBs in its 2 sr-wide field of view. The low-energy threshold of ECLAIRs is well suited for the detection of highly redshifted GRB. The high-energy coverage is extended up to 5 MeV thanks to the non-imaging gamma-ray spectrometer GRM. GRB alerts are sent in real-time to the ground observers community, and a spacecraft slew is performed in orde...

  2. Post-Launch Calibration Support for VIIRS Onboard NASA NPP Spacecraft

    Science.gov (United States)

    Xiong, Xiaoxion; Chiang, Kwo-Fu; McIntire, Jeffrey; Schwaller, Matthew; Butler, James

    2011-01-01

    The NPP Instrument Calibration Support Element (NICSE) is one of the elements within the NASA NPP Science Data Segment (SDS). The primary responsibility of NICSE is to independently monitor and evaluate on-orbit radiometric and geometric performance of the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument and to validate its Sensor Data Record (SDR) [1]. The NICSE interacts and works closely with other SDS Product Evaluation and Analysis Tools Elements (PEATE) and the NPP Science Team (ST) and supports their on-orbit data product calibration and validation efforts. The NICSE also works closely with the NPP Instrument Calibration Support Team (NICST) during sensor pre-launch testing in ambient and thermal vacuum environment [2]. This paper provides an overview of NICSE VIIRS sensor post-launch calibration support with a focus on the use of sensor on-board calibrators (OBC) for the radiometric calibration and characterization. It presents the current status of NICSE post-launch radiometric calibration tool development effort based on its design requirements

  3. Practical on-board weigh-in-motion system for commercial vehicles

    Science.gov (United States)

    Kenyon, Chase H.

    1997-01-01

    Many commercial carriers are currently operating vehicles which are overweight, creating an unsafe and illegal situation. However, the cost to law enforcement agencies to stop vehicles for roadside weight checks is prohibitive, while the cost to the nation in lost travel time adds shipping costs which are reflected in the price of every product transported by truck. Overweight trucks also become a threat to public safety when, on public highways, solid cargo breaks loose or liquid cargo leaks. The solution is an on-board monitoring system. With such a system, trucks under their legal weight limit would be allowed to travel past state borders and checkpoints without being stopped. THis would save money both in law enforcement and shipping costs to the nation as a whole. A properly designed system would also have the capability to warn both the driver and local safety and enforcement personnel when the truck is loaded beyond capacity or any other unsafe condition. This paper will detail a system that would even in early limited production be cost effective for both the law enforcement agencies and the operators of trucking fleets. In full production the systems would be cost effective even for smaller or owner/operator trucks. This is a safety system that could become standard equipment similar to seat belts, ABS, and airbags. The initial testing of sub-assemblies and sub-systems which could be deployed now for beta test has been completed.

  4. Evaluation of Radiometric Performance for the Thermal Infrared Sensor Onboard Landsat 8

    Directory of Open Access Journals (Sweden)

    Huazhong Ren

    2014-12-01

    Full Text Available The radiometric performance of remotely-sensed images is important for the applications of such data in monitoring land surface, ocean and atmospheric status. One requirement placed on the Thermal Infrared Sensor (TIRS onboard Landsat 8 was that the noise-equivalent change in temperature (NEΔT should be ≤0.4 K at 300 K for its two thermal infrared bands. In order to optimize the use of TIRS data, this study investigated the on-orbit NEΔT of the TIRS two bands from a scene-based method using clear-sky images over uniform ground surfaces, including lake, deep ocean, snow, desert and Gobi, as well as dense vegetation. Results showed that the NEΔTs of the two bands were 0.051 and 0.06 K at 300 K, which exceeded the design specification by an order of magnitude. The effect of NEΔT on the land surface temperature (LST retrieval using a split window algorithm was discussed, and the estimated NEΔT could contribute only 3.5% to the final LST error in theory, whereas the required NEΔT could contribute up to 26.4%. Low NEΔT could improve the application of TIRS images. However, efforts are needed in the future to remove the effects of unwanted stray light that appears in the current TIRS images.

  5. Cosmic rays tracks in the PICsIT instrument onboard the INTEGRAL satellite

    Energy Technology Data Exchange (ETDEWEB)

    Labanti, C. [IASF - CNR/INAF Istituto di Astrofisica Spaziale e Fisica cosmica, sezione di Bologna, Via Gobetti 101, 40129 Bologna (Italy); Marisaldi, M. [IASF - CNR/INAF Istituto di Astrofisica Spaziale e Fisica cosmica, sezione di Bologna, Via Gobetti 101, 40129 Bologna (Italy); Segreto, A. [IASF - CNR/INAF Istituto di Astrofisica Spaziale e Fisica cosmica, sezione di Palermo, Via U. La Malfa 153, 90146 Palermo (Italy)

    2006-01-15

    The PICsIT (PIxelated CsI Telescope) instrument is the high energy plane of the IBIS imager onboard the INTEGRAL satellite, launched on October 2002 and currently fully operative. PICsIT consists of a 64x64 detectors array, each composed of a CsI(Tl) scintillating crystal with p-i-n photodiode readout. Since its first in-orbit activation, several count rate spikes have been detected. The tracks in the detector corresponding to those spikes clearly indicate that their origin is the interaction of cosmic rays with the detector or the satellite structure. Several extended elliptical tracks have been detected, indicating the presence of electromagnetic and hadronic showers initiated by primary cosmic rays interacting with the satellite structure. The tracks morphology and statistics is presented. There is strong evidence that tracks events are due to phosphorescence states excited in the CsI(Tl) crystals by a high energy deposit. Since events due to cosmic rays tracks account for a significant fraction of the instrument background, their rejection is important to improve the instrument sensitivity. Tracks rejection is especially important in those instruments, based on large quantities of alkali halide scintillators, designed to trigger on count rate increases, such as gamma-ray burst monitors. In the PICsIT detector operated in photon-by-photon mode, tracks events rejection can be easily accomplished thanks to the tracks peculiar geometrical and timing characteristics.

  6. Application of Analytic Redundancy-based Fault Diagnosis of Sensors to Onboard Maintenance System

    Institute of Scientific and Technical Information of China (English)

    CHI Chengzhi; ZHANG Weiguo; LIU Xiaoxiong

    2012-01-01

    Analytic redundancy-based fault diagnosis technique (ARFDT) is applied to onboard maintenance system (OMS).The principle of the proposed ARFDT scheme is to design a redundancy configuration using ARFDT to enhance the functions of redundancy management and built in test equipment (BITE) monitor.Redundancy configuration for dual-redundancy and analytic redundancy is proposed,in which,the fault diagnosis includes detection and isolation.In order to keep the balance between rapid diagnosis and binary hypothesis,a filter together with an elapsed time limit is designed for sequential probability ratio test (SPRT) in the process of isolation.Diagnosis results would be submitted to central maintenance computer (CMC) together with BITE information.Moreover,by adopting reconstruction,the designed method not only provides analytic redundancy to help redundancy management,but also compensates the output when both of the sensors of the same type are faulty.Our scheme is applied to an aircraft's sensors in a simulation experiment,and the results show that the proposed filter SPRT (FSPRT) saves at least 50% of isolation time than Wald SPRT (WSPRT).Also,effectiveness,practicability and rapidity of the proposed scheme can be successfully achieved in OMS.

  7. Autonomous Onboard Science Image Analysis for Future Mars Rover Missions

    Science.gov (United States)

    Gulick, V. C.; Morris, R. L.; Ruzon, M. A.; Roush, T. L.

    1999-01-01

    To explore high priority landing sites and to prepare for eventual human exploration, future Mars missions will involve rovers capable of traversing tens of kilometers. However, the current process by which scientists interact with a rover does not scale to such distances. Specifically, numerous command cycles are required to complete even simple tasks, such as, pointing the spectrometer at a variety of nearby rocks. In addition, the time required by scientists to interpret image data before new commands can be given and the limited amount of data that can be downlinked during a given command cycle constrain rover mobility and achievement of science goals. Experience with rover tests on Earth supports these concerns. As a result, traverses to science sites as identified in orbital images would require numerous science command cycles over a period of many weeks, months or even years, perhaps exceeding rover design life and other constraints. Autonomous onboard science analysis can address these problems in two ways. First, it will allow the rover to transmit only "interesting" images, defined as those likely to have higher science content. Second, the rover will be able to anticipate future commands. For example, a rover might autonomously acquire and return spectra of "interesting" rocks along with a high resolution image of those rocks in addition to returning the context images in which they were detected. Such approaches, coupled with appropriate navigational software, help to address both the data volume and command cycle bottlenecks that limit both rover mobility and science yield. We are developing fast, autonomous algorithms to enable such intelligent on-board decision making by spacecraft. Autonomous algorithms developed to date have the ability to identify rocks and layers in a scene, locate the horizon, and compress multi-spectral image data. Output from these algorithms could be used to autonomously obtain rock spectra, determine which images should be

  8. Improved Path Planning Onboard the Mars Exploration Rovers

    Science.gov (United States)

    Stentz, Anthony; Ferguson, David; Carsten, Joseph; Rankin, Arturo

    2007-01-01

    A revised version of the AutoNav (autonomous navigation with hazard avoidance) software running onboard each Mars Exploration Rover (MER) affords better obstacle avoidance than does the previous version. Both versions include GESTALT (Grid-based Estimation of Surface Traversability Applied to Local Terrain), a navigation program that generates local-terrain models from stereoscopic image pairs captured by onboard rover cameras; uses this information to evaluate candidate arcs that extend across the terrain from the current rover location; ranks the arcs with respect to hazard avoidance, minimization of steering time, and the direction towards the goal; and combines the rankings in a weighted vote to select an arc, along which the rover is then driven. GESTALT works well in navigating around small isolated obstacles, but tends to fail when the goal is on the other side of a large obstacle or multiple closely spaced small obstacles. When that occurs, the goal seeking votes and hazard avoidance votes conflict severely. The hazard avoidance votes will not allow the rover to drive through the unsafe area, and the waypoint votes will not allow enough deviation from the straight-line path for the rover to get around the hazard. The rover becomes stuck and is unable to reach the goal. The revised version of AutoNav utilizes a global path-planning program, Field D*, to evaluate the cost of traveling from the end of each GESTALT arc to the goal. In the voting process, Field D* arc votes supplant GESTALT goal-seeking arc votes. Hazard avoidance, steering bias, and Field D* votes are merged and the rover is driven a preset distance along the arc with the highest vote. Then new images are acquired and the process as described is repeated until the goal is reached. This new technology allows the rovers to autonomously navigate around much more complex obstacle arrangements than was previously possible. In addition, this improved autonomy enables longer traverses per Sol (a day

  9. Can SAPHIR Instrument Onboard MEGHATROPIQUES Retrieve Hydrometeors and Rainfall Characteristics ?

    Science.gov (United States)

    Goyal, J. M.; Srinivasan, J.; Satheesh, S. K.

    2014-12-01

    MEGHATROPIQUES (MT) is an Indo-French satellite launched in 2011 with the main intention of understanding the water cycle in the tropical region and is a part of GPM constellation. MADRAS was the primary instrument on-board MT to estimate rainfall characteristics, but unfortunately it's scanning mechanism failed obscuring the primary goal of the mission.So an attempt has been made to retrieve rainfall and different hydrometeors using other instrument SAPHIR onboard MT. The most important advantage of using MT is its orbitography which is specifically designed for tropical regions and can reach up to 6 passes per day more than any other satellite currently in orbit. Although SAPHIR is an humidity sounder with six channels centred around 183 GHz channel, it still operates in the microwave region which directly interacts with rainfall, especially wing channels and thus can pick up rainfall signatures. Initial analysis using radiative transfer models also establish this fact .To get more conclusive results using observations, SAPHIR level 1 brightness temperature (BT) data was compared with different rainfall products utilizing the benefits of each product. SAPHIR BT comparison with TRMM 3B42 for one pass clearly showed that channel 5 and 6 have a considerable sensitivity towards rainfall. Following this a huge database of more than 300000 raining pixels of spatially and temporally collocated 3B42 rainfall and corresponding SAPHIR BT for an entire month was created to include all kinds of rainfall events, to attain higher temporal resolution collocated database was also created for SAPHIR BT and rainfall from infrared sensor on geostationary satellite Kalpana 1.These databases were used to understand response of various channels of SAPHIR to different rainfall regimes . TRMM 2A12 rainfall product was also used to identify capabilities of SAPHIR to retrieve cloud and ice water path which also gave significant correlation. Conclusively,we have shown that SAPHIR has

  10. High Energy Particle Accelerators

    CERN Multimedia

    Audio Productions, Inc, New York

    1960-01-01

    Film about the different particle accelerators in the US. Nuclear research in the US has developed into a broad and well-balanced program.Tour of accelerator installations, accelerator development work now in progress and a number of typical experiments with high energy particles. Brookhaven, Cosmotron. Univ. Calif. Berkeley, Bevatron. Anti-proton experiment. Negative k meson experiment. Bubble chambers. A section on an electron accelerator. Projection of new accelerators. Princeton/Penn. build proton synchrotron. Argonne National Lab. Brookhaven, PS construction. Cambridge Electron Accelerator; Harvard/MIT. SLAC studying a linear accelerator. Other research at Madison, Wisconsin, Fixed Field Alternate Gradient Focusing. (FFAG) Oakridge, Tenn., cyclotron. Two-beam machine. Comments : Interesting overview of high energy particle accelerators installations in the US in these early years. .

  11. Improved plasma accelerator

    Science.gov (United States)

    Cheng, D. Y.

    1971-01-01

    Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

  12. Accelerator Technology Division

    Science.gov (United States)

    1992-04-01

    In fiscal year (FY) 1991, the Accelerator Technology (AT) division continued fulfilling its mission to pursue accelerator science and technology and to develop new accelerator concepts for application to research, defense, energy, industry, and other areas of national interest. This report discusses the following programs: The Ground Test Accelerator Program; APLE Free-Electron Laser Program; Accelerator Transmutation of Waste; JAERI, OMEGA Project, and Intense Neutron Source for Materials Testing; Advanced Free-Electron Laser Initiative; Superconducting Super Collider; The High-Power Microwave Program; (Phi) Factory Collaboration; Neutral Particle Beam Power System Highlights; Accelerator Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Accelerator Design and Engineering; Radio-Frequency Technology; Free-Electron Laser Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operations.

  13. Accelerators, Colliders, and Snakes

    Science.gov (United States)

    Courant, Ernest D.

    2003-12-01

    The author traces his involvement in the evolution of particle accelerators over the past 50 years. He participated in building the first billion-volt accelerator, the Brookhaven Cosmotron, which led to the introduction of the "strong-focusing" method that has in turn led to the very large accelerators and colliders of the present day. The problems of acceleration of spin-polarized protons are also addressed, with discussions of depolarizing resonances and "Siberian snakes" as a technique for mitigating these resonances.

  14. The CERN Accelerator School

    CERN Multimedia

    2016-01-01

    Introduction to accelerator physics The CERN Accelerator School: Introduction to Accelerator Physics, which should have taken place in Istanbul, Turkey, later this year has now been relocated to Budapest, Hungary.  Further details regarding the new hotel and dates will be made available as soon as possible on a new Indico site at the end of May.

  15. Accelerators and Dinosaurs

    CERN Multimedia

    Turner, Michael Stanley

    2003-01-01

    Using naturally occuring particles on which to research might have made accelerators become extinct. But in fact, results from astrophysics have made accelerator physics even more important. Not only are accelerators used in hospitals but they are also being used to understand nature's inner workings by searching for Higgs bosons, CP violation, neutrino mass and dark matter (2 pages)

  16. Far field acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Fernow, R.C.

    1995-07-01

    Far fields are propagating electromagnetic waves far from their source, boundary surfaces, and free charges. The general principles governing the acceleration of charged particles by far fields are reviewed. A survey of proposed field configurations is given. The two most important schemes, Inverse Cerenkov acceleration and Inverse free electron laser acceleration, are discussed in detail.

  17. Acceleration: It's Elementary

    Science.gov (United States)

    Willis, Mariam

    2012-01-01

    Acceleration is one tool for providing high-ability students the opportunity to learn something new every day. Some people talk about acceleration as taking a student out of step. In actuality, what one is doing is putting a student in step with the right curriculum. Whole-grade acceleration, also called grade-skipping, usually happens between…

  18. Fast and Adaptive Lossless On-Board Hyperspectral Data Compression System for Space Applications

    Science.gov (United States)

    Aranki, Nazeeh; Bakhshi, Alireza; Keymeulen, Didier; Klimesh, Matthew

    2009-01-01

    Efficient on-board lossless hyperspectral data compression reduces the data volume necessary to meet NASA and DoD limited downlink capabilities. The techniques also improves signature extraction, object recognition and feature classification capabilities by providing exact reconstructed data on constrained downlink resources. At JPL a novel, adaptive and predictive technique for lossless compression of hyperspectral data was recently developed. This technique uses an adaptive filtering method and achieves a combination of low complexity and compression effectiveness that far exceeds state-of-the-art techniques currently in use. The JPL-developed 'Fast Lossless' algorithm requires no training data or other specific information about the nature of the spectral bands for a fixed instrument dynamic range. It is of low computational complexity and thus well-suited for implementation in hardware, which makes it practical for flight implementations of pushbroom instruments. A prototype of the compressor (and decompressor) of the algorithm is available in software, but this implementation may not meet speed and real-time requirements of some space applications. Hardware acceleration provides performance improvements of 10x-100x vs. the software implementation (about 1M samples/sec on a Pentium IV machine). This paper describes a hardware implementation of the JPL-developed 'Fast Lossless' compression algorithm on a Field Programmable Gate Array (FPGA). The FPGA implementation targets the current state of the art FPGAs (Xilinx Virtex IV and V families) and compresses one sample every clock cycle to provide a fast and practical real-time solution for Space applications.

  19. On-Board Visual Tracking with Unmanned Aircraft System (UAS)

    CERN Document Server

    Qadir, Ashraf; Semke, William

    2012-01-01

    This paper presents the development of a real time tracking algorithm that runs on a 1.2 GHz PC/104 computer on-board a small UAV. The algorithm uses zero mean normalized cross correlation to detect and locate an object in the image. A kalman filter is used to make the tracking algorithm computationally efficient. Object position in an image frame is predicted using the motion model and a search window, centered at the predicted position is generated. Object position is updated with the measurement from object detection. The detected position is sent to the motion controller to move the gimbal so that the object stays at the center of the image frame. Detection and tracking is autonomously carried out on the payload computer and the system is able to work in two different methods. The first method starts detecting and tracking using a stored image patch. The second method allows the operator on the ground to select the interest object for the UAV to track. The system is capable of re-detecting an object, in t...

  20. Dust occultation at Titan measured by CDA onboard Cassini

    Science.gov (United States)

    Srama, Ralf; CDA science Team

    2016-10-01

    The Cosmic Dust Analyzer (CDA) onboard Cassini characterized successfully the dust environment at Saturn since 2004. The instrument measures the primary charge, speed, mass and composition of individual submicron and micron sized dust grains. The detection threshold scales with speed^3.5 such that the detection of fast nanograins (~100 km/s) is possible. Saturn's nanodust environment (streams) is studied many years. However, a special geometric condition of Saturn, Cassini and Titan during a Titan flyby in 2014 (DOY 65) provided a special dust occultation opportunity. Titan and its atmosphere blocked the stream of fast nanoparticles such that CDA registered a clear drop in impact rate around closest approach. An analysis of the data allows to constrain the source region of the nanograins, which is compatible with a source region in the ring plane at distances from Saturn between 4 and 8 Saturn radii. Backward and forward modeling was performed leading to dust grain sizes between 3 and 9 nm and speeds between 80 and 150 km/s. The new modeling results also show that Enceladus acts a direct source for nanodust streams leading to the observation of periodic impact rates in the outer Saturn system. Such periodicities were observed recently by CDA and showed a clear signature of the Enceladus orbital period. A second dust occultation opportunity using Titan is planned august 2016.

  1. On-board neural processor design for intelligent multisensor microspacecraft

    Science.gov (United States)

    Fang, Wai-Chi; Sheu, Bing J.; Wall, James

    1996-03-01

    A compact VLSI neural processor based on the Optimization Cellular Neural Network (OCNN) has been under development to provide a wide range of support for an intelligent remote sensing microspacecraft which requires both high bandwidth communication and high- performance computing for on-board data analysis, thematic data reduction, synergy of multiple types of sensors, and other advanced smart-sensor functions. The OCNN is developed with emphasis on its capability to find global optimal solutions by using a hardware annealing method. The hardware annealing function is embedded in the network. It is a parallel version of fast mean-field annealing in analog networks, and is highly efficient in finding globally optimal solutions for cellular neural networks. The OCNN is designed to perform programmable functions for fine-grained processing with annealing control to enhance the output quality. The OCNN architecture is a programmable multi-dimensional array of neurons which are locally connected with their local neurons. Major design features of the OCNN neural processor includes massively parallel neural processing, hardware annealing capability, winner-take-all mechanism, digitally programmable synaptic weights, and multisensor parallel interface. A compact current-mode VLSI design feasibility of the OCNN neural processor is demonstrated by a prototype 5 X 5-neuroprocessor array chip in a 2-micrometers CMOS technology. The OCNN operation theory, architecture, design and implementation, prototype chip, and system applications have been investigated in detail and presented in this paper.

  2. Onboard Atmospheric Modeling and Prediction for Autonomous Aerobraking Missions

    Science.gov (United States)

    Tolson, Robert H.; Prince, Jill L. H.

    2011-01-01

    Aerobraking has proven to be an effective means of increasing the science payload for planetary orbiting missions and/or for enabling the use of less expensive launch vehicles. Though aerobraking has numerous benefits, large operations cost have been required to maintain the aerobraking time line without violating aerodynamic heating or other constraints. Two operations functions have been performed on an orbit by orbit basis to estimate atmospheric properties relevant to aerobraking. The Navigation team typically solves for an atmospheric density scale factor using DSN tracking data and the atmospheric modeling team uses telemetric accelerometer data to recover atmospheric density profiles. After some effort, decisions are made about the need for orbit trim maneuvers to adjust periapsis altitude to stay within the aerobraking corridor. Autonomous aerobraking would reduce the need for many ground based tasks. To be successful, atmospheric modeling must be performed on the vehicle in near real time. This paper discusses the issues associated with estimating the planetary atmosphere onboard and evaluates a number of the options for Mars, Venus and Titan aerobraking missions.

  3. Onboard Data Processor for Change-Detection Radar Imaging

    Science.gov (United States)

    Lou, Yunling; Muellerschoen, Ronald J.; Chien, Steve A.; Saatchi, Sasan S.; Clark, Duane

    2008-01-01

    A computer system denoted a change-detection onboard processor (CDOP) is being developed as a means of processing the digitized output of a synthetic-aperture radar (SAR) apparatus aboard an aircraft or spacecraft to generate images showing changes that have occurred in the terrain below between repeat passes of the aircraft or spacecraft over the terrain. When fully developed, the CDOP is intended to be capable of generating SAR images and/or SAR differential interferograms in nearly real time. The CDOP is expected to be especially useful for understanding some large-scale natural phenomena and/or mitigating natural hazards: For example, it could be used for near-real-time observation of surface changes caused by floods, landslides, forest fires, volcanic eruptions, earthquakes, glaciers, and sea ice movements. It could also be used to observe such longer-term surface changes as those associated with growth of vegetation (relevant to estimation of wildfire fuel loads). The CDOP is, essentially, an interferometric SAR processor designed to operate aboard a radar platform.

  4. Advanced Ionospheric Probe scientific mission onboard FORMOSAT-5 satellite

    Directory of Open Access Journals (Sweden)

    Zai-Wun Lin

    2017-01-01

    Full Text Available Advanced Ionospheric Probe (AIP is a piggyback science payload developed by National Central University for FORMOSAT-5 satellite to explore space weather/climate and seismic precursors associated with strong earthquakes. The AIP is an all-in-one plasma sensor that measures ionospheric plasma concentrations, velocities, and temperatures in a time-sharing way and is capable of measuring ionospheric plasma irregularities at a sample rate up to 8192 Hz over a wide range of spatial scales. Electroformed gold grids used in the AIP in theory construct planar electric potential surfaces better than woven grids. Moreover, a plasma injection test performed in the Space Plasma Simulation Chamber has verified that no significant hysteresis is found in current-voltage curves measured by the AIP. It indicates that the AIP can make an accurate measurement of the ionospheric plasma parameters in space. Finally, Ionospheric Plasma and Electrodynamics Instrument (IPEI observations onboard the ROCSAT-1 satellite are applied to show that the scientific objectives of ionospheric space weather/climate and seismo-ionospheric precursors (SIPs of the FORMOSAT-5/AIP can be fulfilled. The observations reveal that ion parameter global distributions are helpful in studying the formation and variation in temperature crests and troughs in the 2200 - 2300 local time sector, as well as SIPs in the density and the velocity over the epicenter area, which are anticipated for the FORMOSAT-5 satellite orbit.

  5. The K9 On-Board Rover Architecture

    Science.gov (United States)

    Bresina, John L.; Bualat, Maria; Fair, Michael; Washington, Richard; Wright, Anne

    2006-01-01

    This paper describes the software architecture of NASA Ames Research Center s K9 rover. The goal of the onboard software architecture team was to develop a modular, flexible framework that would allow both high- and low-level control of the K9 hardware. Examples of low-level control are the simple drive or pan/tilt commands which are handled by the resource managers, and examples of high-level control are the command sequences which are handled by the conditional executive. In between these two control levels are complex behavioral commands which are handled by the pilot, such as drive to goal with obstacle avoidance or visually servo to a target. This paper presents the design of the architecture as of Fall 2000. We describe the state of the architecture implementation as well as its current evolution. An early version of the architecture was used for K9 operations during a dual-rover field experiment conducted by NASA Ames Research Center (ARC) and the Jet Propulsion Laboratory (JPL) from May 14 to May 16, 2000.

  6. Changing Safety Priorities from Payload Development to Onboard Payload Operations

    Science.gov (United States)

    Kreimer, J.; Biemann, W.; Festa, F.

    2012-01-01

    Safety Analyses for Payload development phases are typically based o n well defined fixed configurations. From safety point of view the main focus during the development phase is on t he design features that will ensure inherent safe launch, on-board installation and usage of the payload in the planned configuration. The complete payload verification including the safety verification and the flight certification is based on that expected scenario. Once the payload is launched and installed on-orbit the focus moves to safe operations in constantly changing configurations over the life-time due t o upgrades, preventive, and corrective maintenance activities. A broader assessment and preparation for recovery procedures would help to streamline this aspect. It would also support the new extended ISS utilization scenario and the changes of the logistic fleet available to the ISS. The challenge to move the safety focus from payload development and design safety features to permanently modified configurations, different upload capabilities and extending life-cycles/time during the operations phase of the payloads can be supported by early definition of operational envelops and resulting safety approval of wider operational flexibility.

  7. Experiment in Onboard Synthetic Aperture Radar Data Processing

    Science.gov (United States)

    Holland, Matthew

    2011-01-01

    Single event upsets (SEUs) are a threat to any computing system running on hardware that has not been physically radiation hardened. In addition to mandating the use of performance-limited, hardened heritage equipment, prior techniques for dealing with the SEU problem often involved hardware-based error detection and correction (EDAC). With limited computing resources, software- based EDAC, or any more elaborate recovery methods, were often not feasible. Synthetic aperture radars (SARs), when operated in the space environment, are interesting due to their relevance to NASAs objectives, but problematic in the sense of producing prodigious amounts of raw data. Prior implementations of the SAR data processing algorithm have been too slow, too computationally intensive, and require too much application memory for onboard execution to be a realistic option when using the type of heritage processing technology described above. This standard C-language implementation of SAR data processing is distributed over many cores of a Tilera Multicore Processor, and employs novel Radiation Hardening by Software (RHBS) techniques designed to protect the component processes (one per core) and their shared application memory from the sort of SEUs expected in the space environment. The source code includes calls to Tilera APIs, and a specialized Tilera compiler is required to produce a Tilera executable. The compiled application reads input data describing the position and orientation of a radar platform, as well as its radar-burst data, over time and writes out processed data in a form that is useful for analysis of the radar observations.

  8. Intelligent on-board system for driving assistance

    Science.gov (United States)

    Rombaut, Michele; Le Fort-Piat, N.

    1995-09-01

    We present in this paper, an electronic copilot embedded in a real car. The system objective is to help the driver by sending alarms or warnings in order to avoid dangerous situtations. An onboard perception system based on CCD cameras and proprioceptive sensors is used ot provide information concerning the environment and the internal state of the vehicle. From this set of information, the copilot is able to analyze the situation and to generate adequate warnings to the driver according to the circumstances. The definition and the development of such a system deal with multisensor data fusion and supervision strategies. The framework of this work was the European Prometheus Pro-Art program. The electronic copilot has been integrated in a prototype vehicle called Prolab2. This French demonstrator integrates the works of nine research laboratories and two car companies: PSA and RENAULT. After a brief presentation of the global demonstrator, we present the two principal parts developed in our laboratory corresponding to the high level modules of the system: the dynamic data manager and the situation supervision.

  9. The Accelerator Reliability Forum

    CERN Document Server

    Lüdeke, Andreas; Giachino, R

    2014-01-01

    A high reliability is a very important goal for most particle accelerators. The biennial Accelerator Reliability Workshop covers topics related to the design and operation of particle accelerators with a high reliability. In order to optimize the over-all reliability of an accelerator one needs to gather information on the reliability of many different subsystems. While a biennial workshop can serve as a platform for the exchange of such information, the authors aimed to provide a further channel to allow for a more timely communication: the Particle Accelerator Reliability Forum [1]. This contribution will describe the forum and advertise it’s usage in the community.

  10. Onboard Classification of Hyperspectral Data on the Earth Observing One Mission

    Science.gov (United States)

    Chien, Steve; Tran, Daniel; Schaffer, Steve; Rabideau, Gregg; Davies, Ashley Gerard; Doggett, Thomas; Greeley, Ronald; Ip, Felipe; Baker, Victor; Doubleday, Joshua; Castano, Rebecca; Mandl, Daniel; Frye, Stuart; Ong, Lawrence; Rogez, Francois; Oaida, Bogdan

    2009-01-01

    Remote-sensed hyperspectral data represents significant challenges in downlink due to its large data volumes. This paper describes a research program designed to process hyperspectral data products onboard spacecraft to (a) reduce data downlink volumes and (b) decrease latency to provide key data products (often by enabling use of lower data rate communications systems). We describe efforts to develop onboard processing to study volcanoes, floods, and cryosphere, using the Hyperion hyperspectral imager and onboard processing for the Earth Observing One (EO-1) mission as well as preliminary work targeting the Hyperspectral Infrared Imager (HyspIRI) mission.

  11. Industrial Application of Accelerators

    CERN Document Server

    CERN. Geneva

    2017-01-01

    At CERN, we are very familiar with large, high energy particle accelerators. However, in the world outside CERN, there are more than 35000 accelerators which are used for applications ranging from treating cancer, through making better electronics to removing harmful micro-organisms from food and water. These are responsible for around $0.5T of commerce each year. Almost all are less than 20 MeV and most use accelerator types that are somewhat different from what is at CERN. These lectures will describe some of the most common applications, some of the newer applications in development and the accelerator technology used for them. It will also show examples of where technology developed for particle physics is now being studied for these applications. Rob Edgecock is a Professor of Accelerator Science, with a particular interest in the medical applications of accelerators. He works jointly for the STFC Rutherford Appleton Laboratory and the International Institute for Accelerator Applications at the Univer...

  12. Industrial Application of Accelerators

    CERN Document Server

    CERN. Geneva

    2017-01-01

    At CERN, we are very familiar with large, high energy particle accelerators. However, in the world outside CERN, there are more than 35000 accelerators which are used for applications ranging from treating cancer, through making better electronics to removing harmful micro-organisms from food and water. These are responsible for around $0.5T of commerce each year. Almost all are less than 20 MeV and most use accelerator types that are somewhat different from what is at CERN. These lectures will describe some of the most common applications, some of the newer applications in development and the accelerator technology used for them. It will also show examples of where technology developed for particle physics is now being studied for these applications. Rob Edgecock is a Professor of Accelerator Science, with a particular interest in the medical applications of accelerators. He works jointly for the STFC Rutherford Appleton Laboratory and the International Institute for Accelerator Applications at the Uni...

  13. Testing universality of cosmic-ray acceleration with proton/helium data from AMS and Voyager-1

    Science.gov (United States)

    Tomassetti, Nicola

    2017-08-01

    The Alpha Magnetic Spectrometer (AMS) experiment onboard the International Space Station (ISS) has recently measured the proton and helium spectra in cosmic rays (CRs) in the GeV-TeV energy region. The spectra of proton and helium are found to progressively harden at rigidity R = pc / Ze ≳ 200 GV, while the proton-to-helium ratio as function of rigidity is found to fall off steadily as p/He ∝R-0.08 . The decrease of the p/He ratio is often interpreted in terms of particle-dependent acceleration, which is in contrast with the universal nature of diffusive-shock-acceleration mechanisms. A different explanation is that the p-He anomaly originates from a flux transition between two components: a sub-TeV flux component (L) provided by hydrogen-rich supernova remnants with soft acceleration spectra, and a multi-TeV component (G) injected by younger sources with amplified magnetic fields and hard spectra. In this scenario the universality of particle acceleration is not violated because both source components provide composition-blind injection spectra. The present work is aimed at testing the universality of CR acceleration using the low-energy part of the CR flux, which is expected to be dominated by the L-type component. However, at kinetic energy of ∼0.5-10 GeV, the CR fluxes are significantly affected by energy losses and solar modulation, hence a proper modeling of Galactic and heliospheric propagation is required. To set the key properties of the L-source component, I have used the Voyager-1 data collected in the interstellar space. To compare my calculations with the AMS data, I have performed a determination of the force-field modulation parameter using neutron monitor measurements. I will show that the recent p-He data reported by AMS and Voyager-1 are in good agreement with the predictions of such a scenario, supporting the hypothesis that CRs are released in the Galaxy by universal, composition-blind accelerators. At energies below ∼0.5 GeV/n, however

  14. All-Sky Monitoring with the Fermi Gamma Ray Burst Monitor

    Science.gov (United States)

    Wilson-Hodge, Colleen A.

    2010-01-01

    We are currently monitoring the transient hard X-ray/soft gamma ray sky using the Gamma Ray Burst Monitor (GBM) on-board Fermi. The twelve GBM NaI detectors span 8 keV to 1MeV, while the two GBM BGO detectors span about 150 keV to 40 MeV. With GBM, we detect transient events on multiple timescales. Brief events, such as Gamma Ray Bursts, Solar flares, and magnetar bursts are detected with on-board triggers. On longer timescales, we use the Earth occultation technique to monitor a number of sources, including X-ray binaries, AGN, and solar flaring activity. To date we have detected 7 sources above 100 keV. Transient activity from accretion-powered pulsars is monitored using epoch-folding techniques. With GBM we track the pulsed flux and frequency for a number of pulsars. We will present highlights of GBM observations on various timescales.

  15. The Close-Up Imager Onboard the ESA ExoMars Rover: Objectives, Description, Operations, and Science Validation Activities

    Science.gov (United States)

    Josset, Jean-Luc; Westall, Frances; Hofmann, Beda A.; Spray, John; Cockell, Charles; Kempe, Stephan; Griffiths, Andrew D.; De Sanctis, Maria Cristina; Colangeli, Luigi; Koschny, Detlef; Föllmi, Karl; Verrecchia, Eric; Diamond, Larryn; Josset, Marie; Javaux, Emmanuelle J.; Esposito, Francesca; Gunn, Matthew; Souchon-Leitner, Audrey L.; Bontognali, Tomaso R. R.; Korablev, Oleg; Erkman, Suren; Paar, Gerhard; Ulamec, Stephan; Foucher, Frédéric; Martin, Philippe; Verhaeghe, Antoine; Tanevski, Mitko; Vago, Jorge L.

    2017-07-01

    The Close-Up Imager (CLUPI) onboard the ESA ExoMars Rover is a powerful high-resolution color camera specifically designed for close-up observations. Its accommodation on the movable drill allows multiple positioning. The science objectives of the instrument are geological characterization of rocks in terms of texture, structure, and color and the search for potential morphological biosignatures. We present the CLUPI science objectives, performance, and technical description, followed by a description of the instrument's planned operations strategy during the mission on Mars. CLUPI will contribute to the rover mission by surveying the geological environment, acquiring close-up images of outcrops, observing the drilling area, inspecting the top portion of the drill borehole (and deposited fines), monitoring drilling operations, and imaging samples collected by the drill. A status of the current development and planned science validation activities is also given.

  16. Acceleration in astrophysics

    Energy Technology Data Exchange (ETDEWEB)

    Colgate, S.A.

    1993-12-31

    The origin of cosmic rays and applicable laboratory experiments are discussed. Some of the problems of shock acceleration for the production of cosmic rays are discussed in the context of astrophysical conditions. These are: The presumed unique explanation of the power law spectrum is shown instead to be a universal property of all lossy accelerators; the extraordinary isotropy of cosmic rays and the limited diffusion distances implied by supernova induced shock acceleration requires a more frequent and space-filling source than supernovae; the near perfect adiabaticity of strong hydromagnetic turbulence necessary for reflecting the accelerated particles each doubling in energy roughly 10{sup 5} to {sup 6} scatterings with negligible energy loss seems most unlikely; the evidence for acceleration due to quasi-parallel heliosphere shocks is weak. There is small evidence for the expected strong hydromagnetic turbulence, and instead, only a small number of particles accelerate after only a few shock traversals; the acceleration of electrons in the same collisionless shock that accelerates ions is difficult to reconcile with the theoretical picture of strong hydromagnetic turbulence that reflects the ions. The hydromagnetic turbulence will appear adiabatic to the electrons at their much higher Larmor frequency and so the electrons should not be scattered incoherently as they must be for acceleration. Therefore the electrons must be accelerated by a different mechanism. This is unsatisfactory, because wherever electrons are accelerated these sites, observed in radio emission, may accelerate ions more favorably. The acceleration is coherent provided the reconnection is coherent, in which case the total flux, as for example of collimated radio sources, predicts single charge accelerated energies much greater than observed.

  17. Onboard screening dockside testing as a new means of managing paralytic shellfish poisoning risks in federally closed waters

    Science.gov (United States)

    DeGrasse, Stacey; Conrad, Stephen; DiStefano, Paul; Vanegas, Camilo; Wallace, David; Jensen, Pete; Hickey, J. Michael; Cenci, Florence; Pitt, Jaclyn; Deardorff, Dave; Rubio, Fernando; Easy, Dorothy; Donovan, Mary Anne; Laycock, Maurice; Rouse, Debbie; Mullen, John

    2014-05-01

    Paralytic shellfish poisoning (PSP) is the foodborne intoxication associated with the consumption of seafood contaminated with naturally occurring neurotoxins known as paralytic shellfish toxins. To protect public health from this potentially fatal syndrome, harvesting closures are implemented when toxins exceed the regulatory action level. Traditional monitoring programs established by state shellfish authorities allow for timely closures in state waters with minimal negative impacts on industry. However, such monitoring programs are not feasible in federal offshore waters given their distance from shore and the range of their spatial coverage. Thus innovative management strategies were investigated for these offshore resources. Georges Bank, an offshore resource with an estimated market value of more than 3 billion in Atlantic surfclams and ocean quahogs, has been closed to harvesting following a temporary ban in 1989 and a subsequent indefinite closure in 1990 due to the risk of PSP. As a means of managing this risk and allowing harvest of safe shellfish from this important resource, the Onboard Screening Dockside Testing Protocol (referred to as the Protocol) was developed by the US Food and Drug Administration (FDA), National Marine Fisheries Service (NMFS), state shellfish control authorities, and industry. The Protocol, which sets forth control measures to ensure product safety and public health protection, was endorsed by the Interstate Shellfish Sanitation Conference (ISSC) for pilot testing. Briefly, the pilot study Protocol required that (1) the fishing vessel receive a permit from NMFS to harvest in closed waters, (2) a miniμm of five shellfish samples per intended harvest lot be tested for PSP toxins onboard, and (3) harvesting only occur when the samples tested from the intended fishing area are negative using the Jellett Rapid Tests or Abraxis Shipboard ELISA kits. Finally, product landed under the Protocol was confirmed to be safe for consumption

  18. Fuel-Cell Power Source Based on Onboard Rocket Propellants

    Science.gov (United States)

    Ganapathi, Gani; Narayan, Sri

    2010-01-01

    The use of onboard rocket propellants (dense liquids at room temperature) in place of conventional cryogenic fuel-cell reactants (hydrogen and oxygen) eliminates the mass penalties associated with cryocooling and boil-off. The high energy content and density of the rocket propellants will also require no additional chemical processing. For a 30-day mission on the Moon that requires a continuous 100 watts of power, the reactant mass and volume would be reduced by 15 and 50 percent, respectively, even without accounting for boiloff losses. The savings increase further with increasing transit times. A high-temperature, solid oxide, electrolyte-based fuel-cell configuration, that can rapidly combine rocket propellants - both monopropellant system with hydrazine and bi-propellant systems such as monomethyl hydrazine/ unsymmetrical dimethyl hydrazine (MMH/UDMH) and nitrogen tetroxide (NTO) to produce electrical energy - overcomes the severe drawbacks of earlier attempts in 1963-1967 of using fuel reforming and aqueous media. The electrical energy available from such a fuel cell operating at 60-percent efficiency is estimated to be 1,500 Wh/kg of reactants. The proposed use of zirconia-based oxide electrolyte at 800-1,000 C will permit continuous operation, very high power densities, and substantially increased efficiency of conversion over any of the earlier attempts. The solid oxide fuel cell is also tolerant to a wide range of environmental temperatures. Such a system is built for easy refueling for exploration missions and for the ability to turn on after several years of transit. Specific examples of future missions are in-situ landers on Europa and Titan that will face extreme radiation and temperature environments, flyby missions to Saturn, and landed missions on the Moon with 14 day/night cycles.

  19. Event processing in X-IFU detector onboard Athena.

    Science.gov (United States)

    Ceballos, M. T.; Cobos, B.; van der Kuurs, J.; Fraga-Encinas, R.

    2015-05-01

    The X-ray Observatory ATHENA was proposed in April 2014 as the mission to implement the science theme "The Hot and Energetic Universe" selected by ESA for L2 (the second Large-class mission in ESA's Cosmic Vision science programme). One of the two X-ray detectors designed to be onboard ATHENA is X-IFU, a cryogenic microcalorimeter based on Transition Edge Sensor (TES) technology that will provide spatially resolved high-resolution spectroscopy. X-IFU will be developed by a consortium of European research institutions currently from France (leadership), Italy, The Netherlands, Belgium, UK, Germany and Spain. From Spain, IFCA (CSIC-UC) is involved in the Digital Readout Electronics (DRE) unit of the X-IFU detector, in particular in the Event Processor Subsytem. We at IFCA are in charge of the development and implementation in the DRE unit of the Event Processing algorithms, designed to recognize, from a noisy signal, the intensity pulses generated by the absorption of the X-ray photons, and lately extract their main parameters (coordinates, energy, arrival time, grade, etc.) Here we will present the design and performance of the algorithms developed for the event recognition (adjusted derivative), and pulse grading/qualification as well as the progress in the algorithms designed to extract the energy content of the pulses (pulse optimal filtering). IFCA will finally have the responsibility of the implementation on board in the (TBD) FPGAs or micro-processors of the DRE unit, where this Event Processing part will take place, to fit into the limited telemetry of the instrument.

  20. Interactive troubleshooting guide for accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Legg, R.; Dunham, B.; Higgins, S.; Kazimi, R.; Kehne, D.; Oren, T.

    1997-12-01

    Modern accelerators face the challenge of supporting increased machine complexity and higher levels of utilization while relying on downsized maintenance and support groups. To improve system availability, reduce reliance on system experts and provide a systematic approach to problem solving, an interactive troubleshooting guide has been implemented for the CEBAF injector at Jefferson lab. This guide, which uses a tree structure with appropriate hypertext links, traces problems from a set of symptoms, through a series of diagnostic tests, to a specific corrective action. This guide is used in conjunction with an active parameter monitoring system that is part of the EPICS control system tool kit. The monitoring system generates operator alarms when injector RF or magnet parameters fall outside pre-set windows. Operators receive immediate feedback when injector components vary from their standard values and the troubleshooting guide provides a systematic means to identify and ultimately correct the problem.

  1. Particle-accelerator decommissioning

    Energy Technology Data Exchange (ETDEWEB)

    Opelka, J.H.; Mundis, R.L.; Marmer, G.J.; Peterson, J.M.; Siskind, B.; Kikta, M.J.

    1979-12-01

    Generic considerations involved in decommissioning particle accelerators are examined. There are presently several hundred accelerators operating in the United States that can produce material containing nonnegligible residual radioactivity. Residual radioactivity after final shutdown is generally short-lived induced activity and is localized in hot spots around the beam line. The decommissioning options addressed are mothballing, entombment, dismantlement with interim storage, and dismantlement with disposal. The recycle of components or entire accelerators following dismantlement is a definite possibility and has occurred in the past. Accelerator components can be recycled either immediately at accelerator shutdown or following a period of storage, depending on the nature of induced activation. Considerations of cost, radioactive waste, and radiological health are presented for four prototypic accelerators. Prototypes considered range from small accelerators having minimal amounts of radioactive mmaterial to a very large accelerator having massive components containing nonnegligible amounts of induced activation. Archival information on past decommissionings is presented, and recommendations concerning regulations and accelerator design that will aid in the decommissioning of an accelerator are given.

  2. Results of the marine biota monitoring during drilling activity on Campos Basin, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Petta, Claudia Brigagao de; Bastos, Fabio; Danielski, Monica; Ferreira, Mariana; Gama, Mariana; Coelho, Ana Paula Athanazio; Maia, Decio [Aecom do Brasil Ltda, Rio de Janeiro, RJ (Brazil)

    2012-07-01

    The Environmental Monitoring Project (PMA) aims to report environmental changes arising from drilling activity, in relation to the marine fauna. This project can also help in the monitoring of accidental spills. Since the professionals spend six hours of the day monitoring the ocean around the rigs, they can locate and identify oil stains, notify the responsible onboard, and also help in the monitoring of the oil stain. Such Project has been developed onboard a drilling unit working in Campos Basin. The results presented here were collected during the drilling activity in Bijupira and Salema fields, by Shell Brasil Petroleo Ltda, from July 13th to October 8th, 2011.

  3. STS-34 MS Chang-Diaz records onboard activity with 16mm camera

    Science.gov (United States)

    1989-01-01

    STS-34 Mission Specialist (MS) Franklin R. Chang-Diaz records forward flight deck activity with ARRIFLEX 16mm camera onboard Atlantis, Orbiter Vehicle (OV) 104. In the background, MS Shannon W. Lucid works at aft flight deck payload station.

  4. First Fluorine and Chlorine Detections on Mars with ChemCam On-Board MSL

    Science.gov (United States)

    Forni, O.; Gaft, M.; Toplis, M.; Clegg, S. M.; Maurice, S.; Wiens, R. C.; Mangold, N.; Sautter, V.; Gasnault, O.; Berger, G.; Nachon, M.; Meslin, P.-Y.; Blaney, D.; Cousin, A.

    2014-07-01

    We report the first detection of fluorine on Mars and the first detection of chlorine with ChemCam onboard MSL/Curiosity. We discuss the plausible mineralogies for these two halogens and their possible origin.

  5. On-Board Engine Exhaust Particulate Matter Sensor for HCCI and Conventional Diesel Engines

    Energy Technology Data Exchange (ETDEWEB)

    Hall, Matt; Matthews, Ron

    2011-09-30

    The goal of the research was to refine and complete development of an on-board particulate matter (PM) sensor for diesel, DISI, and HCCI engines, bringing it to a point where it could be commercialized and marketed.

  6. To the efficiency assessment of the maintenace of aircraft onboard systems

    Directory of Open Access Journals (Sweden)

    N. V. Сhekrizhev

    2015-01-01

    Full Text Available This article considers efficiency assessment of the maintenance of onboard systems of aircraft based on suggested «ideal» model with a set of parameters, criteria and evaluation function.

  7. The China Multimode Microwave Remote Sensor (CMMRS) Onboard the SZ-4 Spaceship

    Institute of Scientific and Technical Information of China (English)

    JIANG Jingshan; LIU Heguang; DONG Xiaolong

    2004-01-01

    In this report, the specifications and some results of the China multimode microwave remote sensor (CMMRS) onboard China's SZ-4 spaceship are described. Technical details and initial processing results of the CMMRS measurement data are reported.

  8. Onboard Robust Visual Tracking for UAVs Using a Reliable Global-Local Object Model

    National Research Council Canada - National Science Library

    Fu, Changhong; Duan, Ran; Kircali, Dogan; Kayacan, Erdal

    2016-01-01

    In this paper, we present a novel onboard robust visual algorithm for long-term arbitrary 2D and 3D object tracking using a reliable global-local object model for unmanned aerial vehicle (UAV) applications, e.g...

  9. Advanced Hybrid On-Board Data Processor - SpaceCube 2.0 Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop advanced on-board processing to meet the requirements of the Decadal Survey missions: advanced instruments (hyper-spectral, SAR, etc) require advanced...

  10. Introduction to beam diagnostics and instrumentation for circular accelerators

    Science.gov (United States)

    Billing, M.

    1992-07-01

    This paper provides a basic overview of beam diagnostics and instrumentation for circular accelerators and storage rings. It addresses the techniques for measuring important accelerator parameters, such as betatron tunes, betatron functions, dispersion functions, beam position, beam size, and damping times. The instrumentation section contains a general description of beam position monitors, beam kickers, and general signal processing techniques. Some examples of actual accelerator measurements are included.

  11. The SpaceCube Family of Hybrid On-Board Science Data Processors: An Update

    Science.gov (United States)

    Flatley, T.

    2012-12-01

    SpaceCube is an FPGA based on-board hybrid science data processing system developed at the NASA Goddard Space Flight Center (GSFC). The goal of the SpaceCube program is to provide 10x to 100x improvements in on-board computing power while lowering relative power consumption and cost. The SpaceCube design strategy incorporates commercial rad-tolerant FPGA technology and couples it with an upset mitigation software architecture to provide "order of magnitude" improvements in computing power over traditional rad-hard flight systems. Many of the missions proposed in the Earth Science Decadal Survey (ESDS) will require "next generation" on-board processing capabilities to meet their specified mission goals. Advanced laser altimeter, radar, lidar and hyper-spectral instruments are proposed for at least ten of the ESDS missions, and all of these instrument systems will require advanced on-board processing capabilities to facilitate the timely conversion of Earth Science data into Earth Science information. Both an "order of magnitude" increase in processing power and the ability to "reconfigure on the fly" are required to implement algorithms that detect and react to events, to produce data products on-board for applications such as direct downlink, quick look, and "first responder" real-time awareness, to enable "sensor web" multi-platform collaboration, and to perform on-board "lossless" data reduction by migrating typical ground-based processing functions on-board, thus reducing on-board storage and downlink requirements. This presentation will highlight a number of SpaceCube technology developments to date and describe current and future efforts, including the collaboration with the U.S. Department of Defense - Space Test Program (DoD/STP) on the STP-H4 ISS experiment pallet (launch June 2013) that will demonstrate SpaceCube 2.0 technology on-orbit.; ;

  12. Leaky Fermi accelerators

    CERN Document Server

    Shah, Kushal; Rom-Kedar, Vered; Turaev, Dmitry

    2015-01-01

    A Fermi accelerator is a billiard with oscillating walls. A leaky accelerator interacts with an environment of an ideal gas at equilibrium by exchange of particles through a small hole on its boundary. Such interaction may heat the gas: we estimate the net energy flow through the hole under the assumption that the particles inside the billiard do not collide with each other and remain in the accelerator for sufficiently long time. The heat production is found to depend strongly on the type of the Fermi accelerator. An ergodic accelerator, i.e. one which has a single ergodic component, produces a weaker energy flow than a multi-component accelerator. Specifically, in the ergodic case the energy gain is independent of the hole size, whereas in the multi-component case the energy flow may be significantly increased by shrinking the hole size.

  13. Accelerator reliability workshop

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, L.; Duru, Ph.; Koch, J.M.; Revol, J.L.; Van Vaerenbergh, P.; Volpe, A.M.; Clugnet, K.; Dely, A.; Goodhew, D

    2002-07-01

    About 80 experts attended this workshop, which brought together all accelerator communities: accelerator driven systems, X-ray sources, medical and industrial accelerators, spallation sources projects (American and European), nuclear physics, etc. With newly proposed accelerator applications such as nuclear waste transmutation, replacement of nuclear power plants and others. Reliability has now become a number one priority for accelerator designers. Every part of an accelerator facility from cryogenic systems to data storage via RF systems are concerned by reliability. This aspect is now taken into account in the design/budget phase, especially for projects whose goal is to reach no more than 10 interruptions per year. This document gathers the slides but not the proceedings of the workshop.

  14. Accelerated Hypertension after Venlafaxine Usage

    Directory of Open Access Journals (Sweden)

    Yüksel Kıvrak

    2014-01-01

    Full Text Available Venlafaxine is the first antidepressant that acts via inhibiting serotonin and noradrenaline reuptake. Hypertension is observed in doses exceeding 300 mg/day and is the most feared complication. We report a patient with accelerated hypertension after venlafaxine use observed at a dose of 150 mg/day. A 23-year-old patient with symptoms of insomnia, depression, anhedonia, fatigue admitted our clinic. Venlafaxine at a dose of 75 mg/day was initiated after he was diagnosed with major depressive disorder. After 5 months, venlafaxine dose was uptitrated to 150 mg/day due to inadequate response to drug. After using venlafaxine for ten months at the dose of 150 mg/day, he admitted our clinic with headache and epistaxis. He was hospitalized after his blood pressure was measured as 210/170 mmHg. No secondary causes for hypertension were found, and venlafaxine treatment was considered possible etiologic factor. After stopping venlafaxine treatment, his blood pressure was reverted back to normal limits. While mild elevation of blood pressure could be observed after venlafaxine treatment, this case shows that accelerated hypertension with a diastolic blood pressure rise above 120 mmHg could be observed at relatively low doses of venlafaxine. Close monitoring of blood pressure is necessary after initiation of treatment, as accelerated hypertension could cause endorgan damage with potentially catastrophic results.

  15. Power Converters for Accelerators

    CERN Document Server

    Visintini, R

    2015-01-01

    Particle accelerators use a great variety of power converters for energizing their sub-systems; while the total number of power converters usually depends on the size of the accelerator or combination of accelerators (including the experimental setup), the characteristics of power converters depend on their loads and on the particle physics requirements: this paper aims to provide an overview of the magnet power converters in use in several facilities worldwide.

  16. Miniaturization Techniques for Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, James E.

    2003-05-27

    The possibility of laser driven accelerators [1] suggests the need for new structures based on micromachining and integrated circuit technology because of the comparable scales. Thus, we are exploring fully integrated structures including sources, optics (for both light and particle) and acceleration in a common format--an accelerator-on-chip (AOC). Tests suggest a number of preferred materials and techniques but no technical or fundamental roadblocks at scales of order 1 {micro}m or larger.

  17. Measurement of Radiation Belt Partcles by MDS-1 Onboard SEDA

    Science.gov (United States)

    Matsumoto, H.; Koshiishi, H.; Goka, T.

    The Space Environment Data Acquisition Equipment (SEDA) is on board the Mission Demonstration Test Satellite-1 (MDS-1) to measure the radiation environment, which was launched into geo-stationary transfer orbit (GTO) on February 4, 2002 with an apogee of about 35,700km, a perigee of about 500 km and an inclination of about 28.5 degrees. SEDA consists of the four instruments. Standard Dose Monitor monitors the electron and proton flux. Dosimeter measures the integrated radiation dose at fifty-six points of the satellite. Heavy Ion Telescope monitors the flux of heavy ions from He to Fe. Magnetometer measures the magnetic field in the magnetosphere. In this paper are described first results and comparison with the ISO standard model for the space environment

  18. Accelerated cleanup risk reduction

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.B.; Aines, R.M.; Blake, R.G.; Copeland, A.B.; Newmark, R.L.; Tompson, A.F.B.

    1998-02-01

    period in which the well was `capped`. Our results show the formation of an inclined gas phase during injection and a fast collapse of the steam zone within an hour of terminating steam injection. The majority of destruction occurs during the collapse phase, when contaminant laden water is drawn back towards the well. Little to no noncondensible gasses are created in this process, removing any possibility of sparging processes interfering with contaminant destruction. Our models suggest that the thermal region should be as hot and as large as possible. To have HPO accepted, we need to demonstrate the in situ destruction of contaminants. This requires the ability to inexpensively sample at depth and under high temperatures. We proved the ability to implies monitoring points at depths exceeding 150 feet in highly heterogeneous soils by use of cone penetrometry. In addition, an extractive system has been developed for sampling fluids and measuring their chemistry under the range of extreme conditions expected. We conducted a collaborative field test of HPO at a Superfund site in southern California where the contaminant is mainly creosote and pentachlorophenol. Field results confirm the destruction of contaminants by HPO, validate our field design from simulations, demonstrate that accurate field measurements of the critical fluid parameters can be obtained using existing monitoring wells (and minimal capital cost) and yield reliable cost estimates for future commercial application. We also tested the in situ microbial filter technology as a means to intercept and destroy the accelerated flow of contaminants caused by the injection of steam. A series of laboratory and field tests revealed that the selected bacterial species effectively degrades trichloroethene in LLNL Groundwater and under LLNL site conditions. In addition, it was demonstrated that the bacteria effectively attach to the LLNL subsurface media. An in-well treatability study indicated that the bacteria

  19. FFAGS for rapid acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Carol J. Johnstone and Shane Koscielniak

    2002-09-30

    When large transverse and longitudinal emittances are to be transported through a circular machine, extremely rapid acceleration holds the advantage that the beam becomes immune to nonlinear resonances because there is insufficient time for amplitudes to build up. Uncooled muon beams exhibit large emittances and require fast acceleration to avoid decay losses and would benefit from this style of acceleration. The approach here employs a fixed-field alternating gradient or FFAG magnet structure and a fixed frequency acceleration system. Acceptance is enhanced by the use only of linear lattice elements, and fixed-frequency rf enables the use of cavities with large shunt resistance and quality factor.

  20. FFAGS FOR MUON ACCELERATION.

    Energy Technology Data Exchange (ETDEWEB)

    BERG,J.S.KAHN,S.PALMER,R.TRBOJEVIC,D.JOHNSTONE,C.KEIL,Y.OGITSU,T.OHMORI,C.SESSLER,A.KOSCIELNIAK,S.

    2003-06-26

    Due to their finite lifetime, muons must be accelerated very rapidly. It is challenging to make the magnets ramp fast enough to accelerate in a synchrotron, and accelerating in a linac is very expensive. One can use a recirculating accelerator (like CEBAF), but one needs a different arc for each turn, and this limits the number of turns one can use to accelerate, and therefore requires significant amounts of RF to achieve the desired energy gain. An alternative method for muon acceleration is using a fixed field alternating gradient (FFAG) accelerator. Such an accelerator has a very large energy acceptance (a factor of two or three), allowing one to use the same arc with a magnetic field that is constant over time. Thus, one can in principle make as many turns as one can tolerate due to muon decay, therefore reducing the RF cost without increasing the arc cost. This paper reviews the current status of research into the design of FFAGs for muon acceleration. Several current designs are described and compared. General design considerations are also discussed.

  1. High Gradient Accelerator Research

    Energy Technology Data Exchange (ETDEWEB)

    Temkin, Richard [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Physics. Plasma Science and Fusion Center

    2016-07-12

    The goal of the MIT program of research on high gradient acceleration is the development of advanced acceleration concepts that lead to a practical and affordable next generation linear collider at the TeV energy level. Other applications, which are more near-term, include accelerators for materials processing; medicine; defense; mining; security; and inspection. The specific goals of the MIT program are: • Pioneering theoretical research on advanced structures for high gradient acceleration, including photonic structures and metamaterial structures; evaluation of the wakefields in these advanced structures • Experimental research to demonstrate the properties of advanced structures both in low-power microwave cold test and high-power, high-gradient test at megawatt power levels • Experimental research on microwave breakdown at high gradient including studies of breakdown phenomena induced by RF electric fields and RF magnetic fields; development of new diagnostics of the breakdown process • Theoretical research on the physics and engineering features of RF vacuum breakdown • Maintaining and improving the Haimson / MIT 17 GHz accelerator, the highest frequency operational accelerator in the world, a unique facility for accelerator research • Providing the Haimson / MIT 17 GHz accelerator facility as a facility for outside users • Active participation in the US DOE program of High Gradient Collaboration, including joint work with SLAC and with Los Alamos National Laboratory; participation of MIT students in research at the national laboratories • Training the next generation of Ph. D. students in the field of accelerator physics.

  2. Towards Real-time, On-board, Hardware-Supported Sensor and Software Health Management for Unmanned Aerial Systems

    Science.gov (United States)

    Schumann, Johann; Rozier, Kristin Y.; Reinbacher, Thomas; Mengshoel, Ole J.; Mbaya, Timmy; Ippolito, Corey

    2013-01-01

    Unmanned aerial systems (UASs) can only be deployed if they can effectively complete their missions and respond to failures and uncertain environmental conditions while maintaining safety with respect to other aircraft as well as humans and property on the ground. In this paper, we design a real-time, on-board system health management (SHM) capability to continuously monitor sensors, software, and hardware components for detection and diagnosis of failures and violations of safety or performance rules during the flight of a UAS. Our approach to SHM is three-pronged, providing: (1) real-time monitoring of sensor and/or software signals; (2) signal analysis, preprocessing, and advanced on the- fly temporal and Bayesian probabilistic fault diagnosis; (3) an unobtrusive, lightweight, read-only, low-power realization using Field Programmable Gate Arrays (FPGAs) that avoids overburdening limited computing resources or costly re-certification of flight software due to instrumentation. Our implementation provides a novel approach of combining modular building blocks, integrating responsive runtime monitoring of temporal logic system safety requirements with model-based diagnosis and Bayesian network-based probabilistic analysis. We demonstrate this approach using actual data from the NASA Swift UAS, an experimental all-electric aircraft.

  3. Accelerated coffee pulp composting.

    Science.gov (United States)

    Sánchez, G; Olguín, E J; Mercado, G

    1999-02-01

    The effect of two abundant, easily available and very low-cost agro-industrial organic residues, i.e., filter cake from the sugar industry and poultry litter, on the composting stabilization time of coffee pulp and on the quality of the produced compost, was evaluated. Piles of one cubic meter were built and monitored within the facilities of a coffee processing plant in the Coatepec region of the State of Veracruz, Mexico. Manual aeration was carried out once a week. A longer thermophilic period (28 days) and a much lower C/N ratio (in the range of 6.9-9.1) were observed in the piles containing the amendments, as compared to the control pile containing only coffee pulp (14 days and a C/N ratio of 14.4, respectively). The maximum assimilation rate of the reducing sugars was 1.6 g kg-1 d-1 (from 7.5 to 5.3%) during the first two weeks when accelerators were present in the proportion of 20% filter cake plus 20% poultry litter, while they accumulated at a rate of 1.2 g kg-1 d-1 (from 7.4 to 9.13%) during the same period in the control pile. The best combination of amendments was 30% filter cake with 20% poultry litter, resulting in a final nitrogen content as high as 4.81%. The second best combination was 20% filter cake with 10% poultry litter, resulting in a compost which also contained a high level of total nitrogen (4.54%). It was concluded that the use of these two residues enhanced the composting process of coffee pulp, promoting a shorter stabilization period and yielding a higher quality of compost.

  4. A line-source method for aligning on-board and other pinhole SPECT systems

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Susu [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27710 (United States); Bowsher, James; Yin, Fang-Fang [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27710 and Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States)

    2013-12-15

    Purpose: In order to achieve functional and molecular imaging as patients are in position for radiation therapy, a robotic multipinhole SPECT system is being developed. Alignment of the SPECT system—to the linear accelerator (LINAC) coordinate frame and to the coordinate frames of other on-board imaging systems such as cone-beam CT (CBCT)—is essential for target localization and image reconstruction. An alignment method that utilizes line sources and one pinhole projection is proposed and investigated to achieve this goal. Potentially, this method could also be applied to the calibration of the other pinhole SPECT systems.Methods: An alignment model consisting of multiple alignment parameters was developed which maps line sources in three-dimensional (3D) space to their two-dimensional (2D) projections on the SPECT detector. In a computer-simulation study, 3D coordinates of line-sources were defined in a reference room coordinate frame, such as the LINAC coordinate frame. Corresponding 2D line-source projections were generated by computer simulation that included SPECT blurring and noise effects. The Radon transform was utilized to detect angles (α) and offsets (ρ) of the line-source projections. Alignment parameters were then estimated by a nonlinear least squares method, based on the α and ρ values and the alignment model. Alignment performance was evaluated as a function of number of line sources, Radon transform accuracy, finite line-source width, intrinsic camera resolution, Poisson noise, and acquisition geometry. Experimental evaluations were performed using a physical line-source phantom and a pinhole-collimated gamma camera attached to a robot.Results: In computer-simulation studies, when there was no error in determining angles (α) and offsets (ρ) of the measured projections, six alignment parameters (three translational and three rotational) were estimated perfectly using three line sources. When angles (α) and offsets (ρ) were provided by

  5. Dosimetry of charged and neutral particles onboard a stratospheric balloon

    Science.gov (United States)

    Dönsdorf, Esther Miriam; Burmeister, Soenke; Heber, Bernd; Benton, Eric; Berger, Thomas

    The interaction of the primary galactic cosmic rays with constituents of the atmosphere leads to a complex secondary radiation field at high altitudes. Of special interest for aviation and thereby also for radiation protection is the height up to 30 km where the radiation field consists of charged and neutral particles. For the determination of the dose rates up to this altitude in the Earth's atmosphere a stratopheric balloon flight will be performed in central Oklahoma which has a cutoff rigidity of about 4 GV. Onboard there will be two different active radiation detector systems to measure the dose of charged and neutral particles in the stratosphere. The first one is a silicon telescope which consists of two 2 cm2 silicon PIN-photodiodes used as semiconductor detectors. This instrument will mainly be used to measure the charged component of the radiation field due to the fact that the silicon detectors have a rather low efficiency for the detection of neutrons and gammas with energies higher than 60 keV. The second instrument is a so called phoswich detector. It is composed of two dissimilar scintillators optically coupled to each other and to a common photomultiplier tube. For this experimental setup a combination of a fast plastic scintillator BC412 and a slow inorganic scintillator CsI(Na) is used. The pulses from the two scintillators will be separated by applying pulse shape analysis. These two different scintillator materials have been chosen because BC412 is hydrogen rich and thus the cross section for fast neutrons is relatively high and CsI(Na) has a high cross section for gamma radiation. The objective of the phoswich detector is to distinguish between gammas and neutrons but it is also possible to measure charged particles with this setup. The aim of the balloon flight is to determine the dose measured with these two different instruments and in particular to differentiate between the dose induced by charged particles and by the different neutral

  6. Onboard Decision Making For a New Class of AUV Science

    Science.gov (United States)

    Rajan, K.; McGann, C.; Py, F.; Thomas, H.; Henthorn, R.; McEwen, R.

    2007-12-01

    Autonomous Underwater Vehicles (AUVs) are an increasingly important tool for oceanographic research. They routinely and cost effectively sample the water column at depths far beyond what humans are capable of visiting. However, control of these platforms has relied on fixed sequences for execution of pre-planned actions limiting their effectiveness for measuring dynamic and episodic ocean phenomenon. At the Monterey Bay Aquarium Research Institute (MBARI), we are developing an advanced Artificial Intelligence (AI) based control system to enable our AUV's to dynamically adapt to the environment by deliberating in-situ about mission plans while tracking onboard resource consumption, dealing with plan failures by allowing dynamic re-planning and being cognizant of vehicle health and safety in the course of executing science plans. Existing behavior-based approaches require an operator to script plans a priori while anticipating where and how the vehicle will transect the water column. While adequate for current needs to do routine pre-defined transects, it has limited flexibility in dealing with opportunistic science needs, is unable to deal with uncertainty in the oceanic environment and puts undue burden on the mission operators to manage complex interactions between behaviors. Our approach, informed by a decades worth of experience in intelligent control of NASA spacecraft, uses a constraint-based representation to manage mission goals, react to exogenous or endogenous failure conditions, respond to sensory feedback by using AI-based search techniques to sort thru a space of likely responses and picking one which is satisfies the completion of mission goals. The system encapsulates the long-standing notion of a sense-deliberate-act cycle at the heart of a control loop and reflects the goal-oriented nature of control allowing operators to specify abstract mission goals rather than detailed command sequences. To date we have tested T- REX (the Teleo

  7. 40 CFR 86.1806-01 - On-board diagnostics.

    Science.gov (United States)

    2010-07-01

    ..., following a request from the manufacturer, revise the size of the orifice to the smallest orifice feasible... checks for computer input components (input values within manufacturer specified ranges), and... battery system component. Possible battery system components requiring monitoring are: battery water level...

  8. Results of TLE and TGF Observation in RELEC Experiment onboard "Vernov" Mission

    Science.gov (United States)

    Klimov, Pavel; Garipov, Gali; Klimov, Stanislav; Rothkaehl, Hanna; Khrenov, Boris; Pozanenko, Alexei; Morozenko, Violetta; Iyudin, Anatoly; Bogomolov, Vitalij V.; Svertilov, Sergey; Panasyuk, Mikhail; Saleev, Kirill; Kaznacheeva, Margarita; Maximov, Ivan

    2016-07-01

    "Vernov" satellite with RELEC experiment onboard was launched on 2014 July, 8 into a polar solar-synchronous orbit. The payload includes DUV ultraviolet and red photometer and DRGE gamma-ray spectrometer providing measurements in 10-3000 keV energy range with four detectors. Both instruments directed to the atmosphere. Total area of DRGE detectors is ˜500 cm ^{2}. The data were recorded both in monitoring and gamma by gamma modes with timing accuracy ˜15 μs. Several TGF candidates with 10-40 gammas in a burst with duration TGF candidates. Possible connection of TGF candidates with electron precipitations is discussed. Observations of transient luminous events (TLEs) were made in UV (240-400 nm) and IR (>610 nm) wavelength bands. More than 8 thousands of flashes with duration between 1 and 128 ms were detected from the atmosphere. Time profiles of detected flashes are very diverse. There are single peak events with significant UV and IR signal, multi-peak structures visible in the both UV and IR channels and very complicated events mixed from UV and IR signals and UV flashes which can continue even during the whole waveform. In addition, there are flashes of various temporal duration and structure measured only in UV wavelength range. Number of UV photons released in the atmosphere varies in a wide range from 10 ^{20} to 10 ^{26}. Apart from the events detected in the thunderstorm regions over the continents, many flashes were observed outside of thunderstorm areas, above the ocean and even at rather high latitudes. Such events are not associated with the thunderstorm and lightning activity measured by WWLLN. Various types of UV and IR flashes measurements and their interpretation, geographical, energy and spectral distribution are presented and discussed.

  9. The estimation of the pollutant emissions on-board vessels by means of numerical methods

    Science.gov (United States)

    Jenaru, A.; Arsenie, P.; Hanzu-Pazara, R.

    2016-08-01

    Protection of the environment, especially within the most recent years, has become a constant problem considered by the states and the governments of the world, which are more and more concerned about the serious problems caused by the continuous deterioration of the environment. The long term effects of pollution on the environment generated by the lack of penalty regulations, have directed the attention of statesmen upon the necessity of the elaboration of normative acts meant to be effective in the continuous fight with it. Maritime transportation generates approximately 4% of the total of the CO2 emissions produced by human activities. This paper is intended to present two methods of estimation of the gases emissions on-board a vessel, methods that are very useful for the crews which are exploiting them. For the determination and the validation of these methods we are going to use the determinations from the tank ship. This ship has as a main propulsion engine Wärtsilä DU Sulzer RT Flex 50 - 6 cylinders that develops a maximal power of 9720 kW and has a permanent monitoring system of the pollutant emissions. The methods we develop here are using the values of the polluting elements from the exhaust gases that are determined at the exit of the vessel from the ship yard, in the framework of the acceptance tests. These values have been introduced within the framework of a matrix in the MATHCAD program. This matrix represents the starting point of the two mentioned methods: the analytical method and the graphical method. During the study we are going to evaluate the development and validation of an analytical tool to be used to determine the standard of emissions aimed at thermal machines on ships. One of the main objectives of this article represents an objective assessment of the expediency of using non-fuels for internal combustion engines in vessels.

  10. Onboard calibration circuit for the DAMPE BGO calorimeter front-end electronics

    Science.gov (United States)

    Zhang, De-Liang; Feng, Chang-Qing; Zhang, Jun-Bin; Wang, Qi; Ma, Si-Yuan; Shen, Zhong-Tao; Jiang, Di; Gao, Shan-Shan; Zhang, Yun-Long; Guo, Jian-Hua; Liu, Shu-Bin; An, Qi

    2016-05-01

    DAMPE (DArk Matter Particle Explorer) is a scientific satellite which is mainly aimed at indirectly searching for dark matter in space. One critical sub-detector of the DAMPE payload is the BGO (bismuth germanium oxide) calorimeter, which contains 1848 PMT (photomultiplier tube) dynodes and 16 FEE (Front-End Electronics) boards. VA160 and VATA160, two 32-channel low power ASICs (Application Specific Integrated Circuits), are adopted as the key components on the FEEs to perform charge measurement for the PMT signals. In order to monitor the parameter drift which may be caused by temperature variation, aging, or other environmental factors, an onboard calibration circuit is designed for the VA160 and VATA160 ASICs. It is mainly composed of a 12-bit DAC (Digital to Analog Converter), an operational amplifier and an analog switch. Test results showed that a dynamic range of 0-30 pC with a precision of 5 fC (Root Meam Square, RMS) was achieved, which covers the VA160’s input range. It can be used to compensate for the temperature drift and test the trigger function of the FEEs. The calibration circuit has been implemented for the front-end electronics of the BGO Calorimeter and verified by all the environmental tests for both Qualification Model and Flight Model of DAMPE. The DAMPE satellite was launched at the end of 2015 and the calibration circuit will operate periodically in space. Supported by Strategic Priority Research Program on Space Science of Chinese Academy of Sciences (XDA04040202-4), and National Basic Research Program (973 Program) of China (2010CB833002) and National Natural Science Foundation of China (11273070)

  11. First results of measurements of extreme ultraviolet radiation onboard a geostationary satellite "ELECTRO-L"

    Science.gov (United States)

    Nusinov, Anatoliy; Kazachevskaya, Tamara; Gonjukh, David

    Measurements of the intensity of EUV emission in the hydrogen Lyman-alpha line were conducted by a broadband photometer VUSS-E onboard geostationary Hydrometeorological satellite "Electro" since March 2011. The solar hydrogen Lyman-alpha line (lambda = 121.6 nm) was monitored. The photomultiplier with LiF window used as a detector insensitive to visible light. Long-wavelength limit of the spectral band sensitivity of the instrument is about 200 nm, so the signal of the device is defined as the flux of solar radiation in the region of 123-200 nm. Its exclusion was carried out by calculation. Since the satellite "Electro" designed for remote sensing of the Earth, its line of sight focused on Earth. Alignment of instrument in the Sun direction was achieved by installing it on the solar panel, periodically moved in the solar direction. Correction of instrument readings, reduced due to the deviation of its axis from the Sun direction, carried out by calculation. Measurements were carried out every second. The first results of the measurements are presented. The difference in absolute calibration Electro-L/VUSS-E is within 5% of corresponding values for measurements TIMED satellite in those days, that is in agreement with laboratory calibrations. It is useful to measure the temperature of the instrument, as its variation on a small interval of time makes change the value of the output signal about 1-2 %. During first year of operation, the sensitivity of the apparatus remained within ± 2% of measured value, significant degradation of sensitivity was not observed. Over time of observation there have been several large flares of X class. The increase of the signal in the ultraviolet range does not exceed a few percent during these flares.

  12. Asia honours accelerator physicists

    CERN Multimedia

    2010-01-01

    "Steve Meyers of Cern and Jie Wei of Beijing's Tsinghua University are the first recipients of a new prize for particle physics. The pair were honoured for their contributions to numerous particle-accelerator projects - including Cern's Large Hadron Collider - by the Asian Committee for Future Accelerators (ACFA)..." (1 paragraph)

  13. COLLECTIVE-FIELD ACCELERATION

    Energy Technology Data Exchange (ETDEWEB)

    Sessler, Andrew M.

    1969-07-04

    Diverse methods proposed for the acceleration of particles by means of collective fields are reviewed. A survey is made of the various currently active experimental programs devoted to investigating collective acceleration, and the present status of the research is briefly noted.

  14. Accelerators Beyond The Tevatron?

    Energy Technology Data Exchange (ETDEWEB)

    Lach, Joseph; /Fermilab

    2010-07-01

    Following the successful operation of the Fermilab superconducting accelerator three new higher energy accelerators were planned. They were the UNK in the Soviet Union, the LHC in Europe, and the SSC in the United States. All were expected to start producing physics about 1995. They did not. Why?

  15. KEK digital accelerator

    Science.gov (United States)

    Iwashita, T.; Adachi, T.; Takayama, K.; Leo, K. W.; Arai, T.; Arakida, Y.; Hashimoto, M.; Kadokura, E.; Kawai, M.; Kawakubo, T.; Kubo, Tomio; Koyama, K.; Nakanishi, H.; Okazaki, K.; Okamura, K.; Someya, H.; Takagi, A.; Tokuchi, A.; Wake, M.

    2011-07-01

    The High Energy Accelerator Research Organization KEK digital accelerator (KEK-DA) is a renovation of the KEK 500 MeV booster proton synchrotron, which was shut down in 2006. The existing 40 MeV drift tube linac and rf cavities have been replaced by an electron cyclotron resonance (ECR) ion source embedded in a 200 kV high-voltage terminal and induction acceleration cells, respectively. A DA is, in principle, capable of accelerating any species of ion in all possible charge states. The KEK-DA is characterized by specific accelerator components such as a permanent magnet X-band ECR ion source, a low-energy transport line, an electrostatic injection kicker, an extraction septum magnet operated in air, combined-function main magnets, and an induction acceleration system. The induction acceleration method, integrating modern pulse power technology and state-of-art digital control, is crucial for the rapid-cycle KEK-DA. The key issues of beam dynamics associated with low-energy injection of heavy ions are beam loss caused by electron capture and stripping as results of the interaction with residual gas molecules and the closed orbit distortion resulting from relatively high remanent fields in the bending magnets. Attractive applications of this accelerator in materials and biological sciences are discussed.

  16. KEK digital accelerator

    Directory of Open Access Journals (Sweden)

    T. Iwashita

    2011-07-01

    Full Text Available The High Energy Accelerator Research Organization KEK digital accelerator (KEK-DA is a renovation of the KEK 500 MeV booster proton synchrotron, which was shut down in 2006. The existing 40 MeV drift tube linac and rf cavities have been replaced by an electron cyclotron resonance (ECR ion source embedded in a 200 kV high-voltage terminal and induction acceleration cells, respectively. A DA is, in principle, capable of accelerating any species of ion in all possible charge states. The KEK-DA is characterized by specific accelerator components such as a permanent magnet X-band ECR ion source, a low-energy transport line, an electrostatic injection kicker, an extraction septum magnet operated in air, combined-function main magnets, and an induction acceleration system. The induction acceleration method, integrating modern pulse power technology and state-of-art digital control, is crucial for the rapid-cycle KEK-DA. The key issues of beam dynamics associated with low-energy injection of heavy ions are beam loss caused by electron capture and stripping as results of the interaction with residual gas molecules and the closed orbit distortion resulting from relatively high remanent fields in the bending magnets. Attractive applications of this accelerator in materials and biological sciences are discussed.

  17. Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams

    Energy Technology Data Exchange (ETDEWEB)

    Siemann, R.H.; /SLAC

    2011-10-24

    Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.

  18. The Accelerated Kepler Problem

    CERN Document Server

    Namouni, Fathi

    2007-01-01

    The accelerated Kepler problem is obtained by adding a constant acceleration to the classical two-body Kepler problem. This setting models the dynamics of a jet-sustaining accretion disk and its content of forming planets as the disk loses linear momentum through the asymmetric jet-counterjet system it powers. The dynamics of the accelerated Kepler problem is analyzed using physical as well as parabolic coordinates. The latter naturally separate the problem's Hamiltonian into two unidimensional Hamiltonians. In particular, we identify the origin of the secular resonance in the accelerated Kepler problem and determine analytically the radius of stability boundary of initially circular orbits that are of particular interest to the problem of radial migration in binary systems as well as to the truncation of accretion disks through stellar jet acceleration.

  19. On Accelerated Black Holes

    CERN Document Server

    Letelier, P S; Letelier, Patricio S.; Oliveira, Samuel R.

    1998-01-01

    The C-metric is revisited and global interpretation of some associated spacetimes are studied in some detail. Specially those with two event horizons, one for the black hole and another for the acceleration. We found that the spacetime fo an accelerated Schwarzschild black hole is plagued by either conical singularities or lack of smoothness and compactness of the black hole horizon. By using standard black hole thermodynamics we show that accelerated black holes have higher Hawking temperature than Unruh temperature. We also show that the usual upper bound on the product of the mass and acceleration parameters (<1/sqrt(27)) is just a coordinate artifact. The main results are extended to accelerated Kerr black holes. We found that they are not changed by the black hole rotation.

  20. Energy harvesting to power sensing hardware onboard wind turbine blade

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Clinton P [Los Alamos National Laboratory; Schichting, Alexander D [Los Alamos National Laboratory; Quellette, Scott [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory

    2009-10-05

    Wind turbines are becoming a larger source of renewable energy in the United States. However, most of the designs are geared toward the weather conditions seen in Europe. Also, in the United States, manufacturers have been increasing the length of the turbine blades, often made of composite materials, to maximize power output. As a result of the more severe loading conditions in the United States and the material level flaws in composite structures, blade failure has been a more common occurrence in the U.S. than in Europe. Therefore, it is imperative that a structural health monitoring system be incorporated into the design of the wind turbines in order to monitor flaws before they lead to a catastrophic failure. Due to the rotation of the turbine and issues related to lightning strikes, the best way to implement a structural health monitoring system would be to use a network of wireless sensor nodes. In order to provide power to these sensor nodes, piezoelectric, thermoelectric and photovoltaic energy harvesting techniques are examined on a cross section of a CX-100 wind turbine blade in order to determine the feasibility of powering individual nodes that would compose the sensor network.

  1. HTML 5 Displays for On-Board Flight Systems

    Science.gov (United States)

    Silva, Chandika

    2016-01-01

    During my Internship at NASA in the summer of 2016, I was assigned to a project which dealt with developing a web-server that would display telemetry and other system data using HTML 5, JavaScript, and CSS. By doing this, it would be possible to view the data across a variety of screen sizes, and establish a standard that could be used to simplify communication and software development between NASA and other countries. Utilizing a web- approach allowed us to add in more functionality, as well as make the displays more aesthetically pleasing for the users. When I was assigned to this project my main task was to first establish communication with the current display server. This display server would output data from the on-board systems in XML format. Once communication was established I was then asked to create a dynamic telemetry table web page that would update its header and change as new information came in. After this was completed, certain minor functionalities were added to the table such as a hide column and filter by system option. This was more for the purpose of making the table more useful for the users, as they can now filter and view relevant data. Finally my last task was to create a graphical system display for all the systems on the space craft. This was by far the most challenging part of my internship as finding a JavaScript library that was both free and contained useful functions to assist me in my task was difficult. In the end I was able to use the JointJs library and accomplish the task. With the help of my mentor and the HIVE lab team, we were able to establish stable communication with the display server. We also succeeded in creating a fully dynamic telemetry table and in developing a graphical system display for the advanced modular power system. Working in JSC for this internship has taught me a lot about coding in JavaScript and HTML 5. I was also introduced to the concept of developing software as a team, and exposed to the different

  2. Thermal Imaging Performance of TIR Onboard the Hayabusa2 Spacecraft

    Science.gov (United States)

    Arai, Takehiko; Nakamura, Tomoki; Tanaka, Satoshi; Demura, Hirohide; Ogawa, Yoshiko; Sakatani, Naoya; Horikawa, Yamato; Senshu, Hiroki; Fukuhara, Tetsuya; Okada, Tatsuaki

    2017-07-01

    The thermal infrared imager (TIR) is a thermal infrared camera onboard the Hayabusa2 spacecraft. TIR will perform thermography of a C-type asteroid, 162173 Ryugu (1999 JU3), and estimate its surface physical properties, such as surface thermal emissivity ɛ , surface roughness, and thermal inertia Γ, through remote in-situ observations in 2018 and 2019. In prelaunch tests of TIR, detector calibrations and evaluations, along with imaging demonstrations, were performed. The present paper introduces the experimental results of a prelaunch test conducted using a large-aperture collimator in conjunction with TIR under atmospheric conditions. A blackbody source, controlled at constant temperature, was measured using TIR in order to construct a calibration curve for obtaining temperatures from observed digital data. As a known thermal emissivity target, a sandblasted black almite plate warmed from the back using a flexible heater was measured by TIR in order to evaluate the accuracy of the calibration curve. As an analog target of a C-type asteroid, carbonaceous chondrites (50 mm × 2 mm in thickness) were also warmed from the back and measured using TIR in order to clarify the imaging performance of TIR. The calibration curve, which was fitted by a specific model of the Planck function, allowed for conversion to the target temperature within an error of 1°C (3σ standard deviation) for the temperature range of 30 to 100°C. The observed temperature of the black almite plate was consistent with the temperature measured using K-type thermocouples, within the accuracy of temperature conversion using the calibration curve when the temperature variation exhibited a random error of 0.3 °C (1σ ) for each pixel at a target temperature of 50°C. TIR can resolve the fine surface structure of meteorites, including cracks and pits with the specified field of view of 0.051°C (328 × 248 pixels). There were spatial distributions with a temperature variation of 3°C at the setting

  3. Thermal Imaging Performance of TIR Onboard the Hayabusa2 Spacecraft

    Science.gov (United States)

    Arai, Takehiko; Nakamura, Tomoki; Tanaka, Satoshi; Demura, Hirohide; Ogawa, Yoshiko; Sakatani, Naoya; Horikawa, Yamato; Senshu, Hiroki; Fukuhara, Tetsuya; Okada, Tatsuaki

    2017-03-01

    The thermal infrared imager (TIR) is a thermal infrared camera onboard the Hayabusa2 spacecraft. TIR will perform thermography of a C-type asteroid, 162173 Ryugu (1999 JU3), and estimate its surface physical properties, such as surface thermal emissivity ɛ , surface roughness, and thermal inertia Γ, through remote in-situ observations in 2018 and 2019. In prelaunch tests of TIR, detector calibrations and evaluations, along with imaging demonstrations, were performed. The present paper introduces the experimental results of a prelaunch test conducted using a large-aperture collimator in conjunction with TIR under atmospheric conditions. A blackbody source, controlled at constant temperature, was measured using TIR in order to construct a calibration curve for obtaining temperatures from observed digital data. As a known thermal emissivity target, a sandblasted black almite plate warmed from the back using a flexible heater was measured by TIR in order to evaluate the accuracy of the calibration curve. As an analog target of a C-type asteroid, carbonaceous chondrites ( 50 mm × 2 mm in thickness) were also warmed from the back and measured using TIR in order to clarify the imaging performance of TIR. The calibration curve, which was fitted by a specific model of the Planck function, allowed for conversion to the target temperature within an error of 1 ∘C ( 3σ standard deviation) for the temperature range of 30 to 100 ∘C. The observed temperature of the black almite plate was consistent with the temperature measured using K-type thermocouples, within the accuracy of temperature conversion using the calibration curve when the temperature variation exhibited a random error of 0.3 ∘C ( 1σ ) for each pixel at a target temperature of 50 ∘C. TIR can resolve the fine surface structure of meteorites, including cracks and pits with the specified field of view of 0.051∘ ( 328 × 248 pixels). There were spatial distributions with a temperature variation of 3

  4. A ΔE-E semiconductor detector combined with CsI(Tl) crystal for monitoring the relative electrons flux generated in interaction of accelerated nuclei beam on thin targets

    Science.gov (United States)

    Cruceru, M.; Afanasiev, S.; Dryablov, D.; Dubinchik, B.; Igamkulov, Z.

    2015-07-01

    Experimental data are presented, obtained with a ΔE-E semiconductor detector combined with a CsI(Tl) inorganic scintillator crystal. The interaction between a beam of accelerated nuclei and thin targets is analyzed. We show that, as a result of this interaction, the secondary particles, including δ-electrons, are generated. In the case of δ-electrons it is possible to study the beam characteristics and the nature of interaction processes, which is of great interest in high-energy interaction.

  5. Particle acceleration by plasma

    CERN Document Server

    Ogata, A

    2002-01-01

    Plasma acceleration is carried out by using potential of plasma wave. It is classified by generation method of plasma wave such as the laser wake-field acceleration and the beat wave acceleration. Other method using electron beam is named the plasma wake-field acceleration (or beam wake-field acceleration). In this paper, electron acceleration by laser wake-field in gas plasma, ion source by laser radiation of solid target and nanoion beam generation by one component of plasma in trap are explained. It is an applicable method that ions, which run out from the solid target irradiated by laser, are used as ion source of accelerator. The experimental system using 800 nm laser, 50 mJ pulse energy and 50 fs pulse width was studied. The laser intensity is 4x10 sup 1 sup 6 Wcm sup - sup 2 at the focus. The target film of metal and organic substance film was used. When laser irradiated Al target, two particles generated, in front and backward. It is new fact that the neutral particle was obtained in front, because it...

  6. The miniature accelerator

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    The image that most people have of CERN is of its enormous accelerators and their capacity to accelerate particles to extremely high energies. But thanks to some cutting-edge studies on beam dynamics and radiofrequency technology, along with innovative construction techniques, teams at CERN have now created the first module of a brand-new accelerator, which will be just 2 metres long. The potential uses of this miniature accelerator will include deployment in hospitals for the production of medical isotopes and the treatment of cancer. It’s a real David-and-Goliath story.   Serge Mathot, in charge of the construction of the "mini-RFQ", pictured with the first of the four modules that will make up the miniature accelerator. The miniature accelerator consists of a radiofrequency quadrupole (RFQ), a component found at the start of all proton accelerator chains around the world, from the smallest to the largest. The LHC is designed to produce very high-intensity beams ...

  7. Cosmic particle acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Zimbardo, Gaetano; Perri, Silvia [Universita della Calabria, Dipartimento di Fisica, 87036 Rende (Italy)

    2014-07-01

    The most popular mechanism for the acceleration of cosmic rays, which is thought to operate in supernova remnant shocks as well as at heliospheric shocks, is the diffusive shock acceleration, which is a Fermi mechanism based on normal diffusion. On the other hand, in the last few years it has been shown that the transport of plasma particles in the presence of electric and magnetic turbulence can be superdiffusive rather than normal diffusive. The term 'superdiffusive' refers to the mean square displacement of particle positions growing superlinearly with time, as compared to the normal linear growth. In particular, superdiffusion is characterized by a non Gaussian statistical process called Levy random walk. We show how diffusive shock acceleration is modified by superdiffusion, and how this yields new predictions for the cosmic ray spectral index, for the acceleration time, and for the spatial profile of energetic particles. A comparison with observations of particle acceleration at heliospheric shocks and at supernova remnant shocks is done. We discuss how superdiffusive shock acceleration allows to explain the observations of hard ion spectra at the solar wind termination shock detected by Voyager 2, of hard radio spectra due to synchrotron emission of electrons accelerated at supernova remnant shocks, and how it can help to explain the observations of 'thin rims' in the X-ray synchrotron emission.

  8. Multicavity proton cyclotron accelerator

    Directory of Open Access Journals (Sweden)

    J. L. Hirshfield

    2002-08-01

    Full Text Available A mechanism for acceleration of protons is described, in which energy gain occurs near cyclotron resonance as protons drift through a sequence of rotating-mode TE_{111} cylindrical cavities in a strong nearly uniform axial magnetic field. Cavity resonance frequencies decrease in sequence from one another with a fixed frequency interval Δf between cavities, so that synchronism can be maintained between the rf fields and proton bunches injected at intervals of 1/Δf. An example is presented in which a 122 mA, 1 MeV proton beam is accelerated to 961 MeV using a cascade of eight cavities in an 8.1 T magnetic field, with the first cavity resonant at 120 MHz and with Δf=8 MHz. Average acceleration gradient exceeds 40 MV/m, average effective shunt impedance is 223 MΩ/m, but maximum surface field in the cavities does not exceed 7.2 MV/m. These features occur because protons make many orbital turns in each cavity and thus experience acceleration from each cavity field many times. Longitudinal and transverse stability appear to be intrinsic properties of the acceleration mechanism, and an example to illustrate this is presented. This acceleration concept could be developed into a proton accelerator for a high-power neutron spallation source, such as that required for transmutation of nuclear waste or driving a subcritical fission burner, provided a number of significant practical issues can be addressed.

  9. The GLAST Burst Monitor (GBM)

    OpenAIRE

    Lichti, G. G.; Briggs, M.S.; Diehl, R.; Fishman, G.; Georgii, R.; Kippen, R. M.; Kouveliotou, C.; Meegan, C.; Paciesas, W.; Preece, R.; Schoenfelder, V.; von Kienlin, A.

    2001-01-01

    The selection of the GLAST burst monitor (GBM) by NASA will allow the investigation of the relation between the keV and the MeV-GeV emission from gamma-ray bursts. The GBM consists of 12 NaI and 2 BGO crystals allowing a continuous measurement of the energy spectra of gamma-ray bursts from ~5 keV to \\~30 MeV. One feature of the GBM is its high time resolution for time-resolved gamma-ray spectroscopy. Moreover the arrangement of the NaI crystals allows a rapid on-board location (

  10. BASIC REQUIREMENTS AND PRINCIPLES OF CREATION ONBOARD DIAGNOSTIC SYSTEMS OF LOCOMOTIVES

    Directory of Open Access Journals (Sweden)

    YE. B. Bodnar

    2014-01-01

    Full Text Available Purpose. Justification of the basic principles of construction on-board diagnostic systems locomotive and choose from high-performance and reliable interface for the exchange of information on-board diagnostic systems. Methodology. Problem of getting correct and adequate information about the technical state of the technical object is solved with the use and compliance of the fundamental principles of modern computers. Findings. High-performance and reliable interface to exchange messages between different units of management systems and on-board diagnostic systems was selected. Properties which are required high data rate, high reliability and low error rate of information transfer. Originality. The main principles of building on-board diagnostic systems which ensure compliance locomotives accumulation of accurate and adequate information about the technical condition which is necessary to organize its maintenance and repair were formulated. Practical value. Diagnostic equipment designed with use of requirements set forth above and principles will affect the technical condition of the engine, increasing the likelihood of uptime, productivity and locomotive repair teams. The introduction of on-board diagnostic systems and stationary locomotives will significantly improve the system and optimize their maintenance costs of maintenance and repairs. Besides, information about diagnostic parameters changing accumulated with the aim of airborne systems will be used in order to create mathematical models that, in turn, will organize a system of maintenance and predict the technical condition of locomotives

  11. Application of Accelerators and Storage Rings: Accelerators in Medicine

    CERN Document Server

    Amaldi, U

    2013-01-01

    This document is part of Subvolume C 'Accelerators and Colliders' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the the Section '11.3 Accelerators in Medicine' of the Chapter '11 Application of Accelerators and Storage Rings' with the content: 11.3 Accelerators in Medicine 11.3.1 Accelerators and Radiopharmaceuticals 11.3.2 Accelerators and Cancer Therapy

  12. 15 CFR 971.603 - At-sea monitoring.

    Science.gov (United States)

    2010-01-01

    ...) Nutrients. (ii) Endangered species (observations). (iii) Salinity, temperature, density. (iv) Currents and... Administrator. (j) Pursuant to section 114(1) of the Act, the Administrator intends to place observers onboard... of monitoring strategies, both in terms of protecting the environment and in being...

  13. Confronting Twin Paradox Acceleration

    Science.gov (United States)

    Murphy, Thomas W.

    2016-05-01

    The resolution to the classic twin paradox in special relativity rests on the asymmetry of acceleration. Yet most students are not exposed to a satisfactory analysis of what exactly happens during the acceleration phase that results in the nonaccelerated observer's more rapid aging. The simple treatment presented here offers both graphical and quantitative solutions to the problem, leading to the correct result that the acceleration-induced age gap is 2Lβ years when the one-way distance L is expressed in light-years and velocity β ≡v/c .

  14. Acoustic multivariate condition monitoring - AMCM

    Energy Technology Data Exchange (ETDEWEB)

    Rosenhave, P.E. [Vestfold College, Maritime Dept., Toensberg (Norway)

    1997-12-31

    In Norway, Vestfold College, Maritime Department presents new opportunities for non-invasive, on- or off-line acoustic monitoring of rotating machinery such as off-shore pumps and diesel engines. New developments within acoustic sensor technology coupled with chemometric data analysis of complex signals now allow condition monitoring of hitherto unavailable flexibility and diagnostic specificity. Chemometrics paired with existing knowledge yields a new and powerful tool for condition monitoring. By the use of multivariate techniques and acoustics it is possible to quantify wear and tear as well as predict the performance of working components in complex machinery. This presentation describes the AMCM method and one result of a feasibility study conducted onboard the LPG/C `Norgas Mariner` owned by Norwegian Gas Carriers as (NGC), Oslo. (orig.) 6 refs.

  15. Tests of shielding effectiveness of Kevlar and Nextel onboard the International Space Station and the Foton-M3 capsule.

    Science.gov (United States)

    Pugliese, M; Bengin, V; Casolino, M; Roca, V; Zanini, A; Durante, M

    2010-08-01

    Radiation assessment and protection in space is the first step in planning future missions to the Moon and Mars, where mission and number of space travelers will increase and the protection of the geomagnetic shielding against the cosmic radiation will be absent. In this framework, the shielding effectiveness of two flexible materials, Kevlar and Nextel, were tested, which are largely used in the construction of spacecrafts. Accelerator-based tests clearly demonstrated that Kevlar is an excellent shield for heavy ions, close to polyethylene, whereas Nextel shows poor shielding characteristics. Measurements on flight performed onboard of the International Space Station and of the Foton-M3 capsule have been carried out with special attention to the neutron component; shielded and unshielded detectors (thermoluminescence dosemeters, bubble detectors) were exposed to a real radiation environment to test the shielding properties of the materials under study. The results indicate no significant effects of shielding, suggesting that thin shields in low-Earth Orbit have little effect on absorbed dose.

  16. A comprehensive review of on-board State-of-Available-Power prediction techniques for lithium-ion batteries in electric vehicles

    Science.gov (United States)

    Farmann, Alexander; Sauer, Dirk Uwe

    2016-10-01

    This study provides an overview of available techniques for on-board State-of-Available-Power (SoAP) prediction of lithium-ion batteries (LIBs) in electric vehicles. Different approaches dealing with the on-board estimation of battery State-of-Charge (SoC) or State-of-Health (SoH) have been extensively discussed in various researches in the past. However, the topic of SoAP prediction has not been explored comprehensively yet. The prediction of the maximum power that can be applied to the battery by discharging or charging it during acceleration, regenerative braking and gradient climbing is definitely one of the most challenging tasks of battery management systems. In large lithium-ion battery packs because of many factors, such as temperature distribution, cell-to-cell deviations regarding the actual battery impedance or capacity either in initial or aged state, the use of efficient and reliable methods for battery state estimation is required. The available battery power is limited by the safe operating area (SOA), where SOA is defined by battery temperature, current, voltage and SoC. Accurate SoAP prediction allows the energy management system to regulate the power flow of the vehicle more precisely and optimize battery performance and improve its lifetime accordingly. To this end, scientific and technical literature sources are studied and available approaches are reviewed.

  17. Vibration control in accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Montag, C.

    2011-01-01

    In the vast majority of accelerator applications, ground vibration amplitudes are well below tolerable magnet jitter amplitudes. In these cases, it is necessary and sufficient to design a rigid magnet support structure that does not amplify ground vibration. Since accelerator beam lines are typically installed at an elevation of 1-2m above ground level, special care has to be taken in order to avoid designing a support structure that acts like an inverted pendulum with a low resonance frequency, resulting in untolerable lateral vibration amplitudes of the accelerator components when excited by either ambient ground motion or vibration sources within the accelerator itself, such as cooling water pumps or helium flow in superconducting magnets. In cases where ground motion amplitudes already exceed the required jiter tolerances, for instance in future linear colliders, passive vibration damping or active stabilization may be considered.

  18. Compact particle accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Elizondo-Decanini, Juan M.

    2017-08-29

    A compact particle accelerator having an input portion configured to receive power to produce particles for acceleration, where the input portion includes a switch, is provided. In a general embodiment, a vacuum tube receives particles produced from the input portion at a first end, and a plurality of wafer stacks are positioned serially along the vacuum tube. Each of the plurality of wafer stacks include a dielectric and metal-oxide pair, wherein each of the plurality of wafer stacks further accelerate the particles in the vacuum tube. A beam shaper coupled to a second end of the vacuum tube shapes the particles accelerated by the plurality of wafer stacks into a beam and an output portion outputs the beam.

  19. Rejuvenating CERN's Accelerators

    CERN Multimedia

    2004-01-01

    In the coming years and especially in 2005, CERN's accelerators are going to receive an extensive renovation programme to ensure they will perform reliably and effectively when the LHC comes into service.

  20. Joint International Accelerator School

    CERN Multimedia

    CERN Accelerator School

    2014-01-01

    The CERN and US Particle Accelerator Schools recently organised a Joint International Accelerator School on Beam Loss and Accelerator Protection, held at the Hyatt Regency Hotel, Newport Beach, California, USA from 5-14 November 2014. This Joint School was the 13th in a series of such schools, which started in 1985 and also involves the accelerator communities in Japan and Russia.   Photo courtesy of Alfonse Pham, Michigan State University.   The school attracted 58 participants representing 22 different nationalities, with around half from Europe and the other half from Asia and the Americas. The programme comprised 26 lectures, each of 90 minutes, and 13 hours of case study. The students were given homework each day and had an opportunity to sit a final exam, which counted towards university credit. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and quality of their lectures. Initial dis...

  1. Dielectric assist accelerating structure

    Science.gov (United States)

    Satoh, D.; Yoshida, M.; Hayashizaki, N.

    2016-01-01

    A higher-order TM02 n mode accelerating structure is proposed based on a novel concept of dielectric loaded rf cavities. This accelerating structure consists of ultralow-loss dielectric cylinders and disks with irises which are periodically arranged in a metallic enclosure. Unlike conventional dielectric loaded accelerating structures, most of the rf power is stored in the vacuum space near the beam axis, leading to a significant reduction of the wall loss, much lower than that of conventional normal-conducting linac structures. This allows us to realize an extremely high quality factor and a very high shunt impedance at room temperature. A simulation of a 5 cell prototype design with an existing alumina ceramic indicates an unloaded quality factor of the accelerating mode over 120 000 and a shunt impedance exceeding 650 M Ω /m at room temperature.

  2. Induced Seismicity Monitoring System

    Science.gov (United States)

    Taylor, S. R.; Jarpe, S.; Harben, P.

    2014-12-01

    There are many seismological aspects associated with monitoring of permanent storage of carbon dioxide (CO2) in geologic formations. Many of these include monitoring underground gas migration through detailed tomographic studies of rock properties, integrity of the cap rock and micro seismicity with time. These types of studies require expensive deployments of surface and borehole sensors in the vicinity of the CO2 injection wells. Another problem that may exist in CO2 sequestration fields is the potential for damaging induced seismicity associated with fluid injection into the geologic reservoir. Seismic hazard monitoring in CO2 sequestration fields requires a seismic network over a spatially larger region possibly having stations in remote settings. Expensive observatory-grade seismic systems are not necessary for seismic hazard deployments or small-scale tomographic studies. Hazard monitoring requires accurate location of induced seismicity to magnitude levels only slightly less than that which can be felt at the surface (e.g. magnitude 1), and the frequencies of interest for tomographic analysis are ~1 Hz and greater. We have developed a seismo/acoustic smart sensor system that can achieve the goals necessary for induced seismicity monitoring in CO2 sequestration fields. The unit is inexpensive, lightweight, easy to deploy, can operate remotely under harsh conditions and features 9 channels of recording (currently 3C 4.5 Hz geophone, MEMS accelerometer and microphone). An on-board processor allows for satellite transmission of parameter data to a processing center. Continuous or event-detected data is kept on two removable flash SD cards of up to 64+ Gbytes each. If available, data can be transmitted via cell phone modem or picked up via site visits. Low-power consumption allows for autonomous operation using only a 10 watt solar panel and a gel-cell battery. The system has been successfully tested for long-term (> 6 months) remote operations over a wide range

  3. Maritime DC Microgrids - A Combination of Microgrid Technologies and Maritime Onboard Power System for Future Ships

    DEFF Research Database (Denmark)

    Jin, Zheming; Savaghebi, Mehdi; Quintero, Juan Carlos Vasquez;

    2016-01-01

    system. Not only frequency-related constraints are eliminated, which allows high-speed smaller generators to be used, but also new fault-tolerant configurations involving power electronics, generation control, as well as smart systemic management. For these reasons, DC power systems become natural...... power supply for a short time, which make the system highly consist with DC microgrids. In this content, it is foreseeable that the advanced research outcomes in the field of DC microgrid are also compatible with maritime onboard power systems. In this paper, DC power architectures, control......DC power distribution system is being considered as an attractive alternative to its traditional AC counterpart in many fields of applications and, in particular, for maritime onboard power systems. The adoption of DC power architecture would bring a broad range of benefits to the onboard power...

  4. Contribution of magnetic measurements onboard NetLander to Mars exploration

    DEFF Research Database (Denmark)

    Menvielle, M.; Musmann, G.; Kuhnke, F.

    2000-01-01

    between the environment of the planet and solar radiation, and a secondary source, the electric currents induced in the conductive planet. The continuous recording of the time variations of the magnetic field at the surface of Mars by means of three component magnetometers installed onboard Net......In the frame of the international cooperation for Mars exploration, a set of 4 NetLanders developed by an European consortium is expected to land on the planet during the forthcoming years. Among other instruments, the geophysical package of each lander will include a magnetometer. The different...... possible contributions of magnetic measurements onboard the NetLander stations are presented. Intrinsic planetary field and remanent magnetisation investigations by means of magnetometers onboard a network of landers are first considered, and the information that can be thus derived on the Martian core...

  5. A Novel Onboard-gateway-based Mechanism to Improve TCP Performance in Aeronautical Satellite Networks

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The IP-based networks on aircraft serve to support Internet services via satellites. However, in aeronautical satellite hybrid networks, the TCP protocol performance often deteriorates due to improper decreases and slow recovery of the congestion window. This paper proposes a window size determination and notification mechanism, onboard-gateway-based mechanism (OGBM), which is based on the onboard gateway in the networks on aircraft. A cross-layer approach is adopted by the onboard gateway to obtain the satellite link bandwidth information. And then, by the gateway, through changing the receiver's advertised window field in ACK packets, TCP sources are notified of the window size of each TCP source calculated on the ground of bandwidth delay product and flow numbers. The mechanism is able to avoid improper changes of TCP window and serve multiple users. Simulation results show that the mechanism with the fairness index close to 1 improves TCP performance in aeronautical satellite networks.

  6. LHCb GPU Acceleration Project

    CERN Document Server

    AUTHOR|(SzGeCERN)744808; Campora Perez, Daniel Hugo; Neufeld, Niko; Vilasis Cardona, Xavier

    2016-01-01

    The LHCb detector is due to be upgraded for processing high-luminosity collisions, which will increase the load on its computation infrastructure from 100 GB/s to 4 TB/s, encouraging us to look for new ways of accelerating the Online reconstruction. The Coprocessor Manager is our new framework for integrating LHCb’s existing computation pipelines with massively parallel algorithms running on GPUs and other accelerators. This paper describes the system and analyzes its performance.

  7. Accelerating News Issue 2

    CERN Document Server

    Kahle, K; Wildner, E

    2012-01-01

    In this summer issue we look at how developments in collimator materials could have applications in aerospace and beyond, and how Polish researchers are harnessing accelerators for medical and industrial uses. We see how the LHC luminosity upgrade is linking with European industry and US researchers, and how the neutrino oscillation community is progressing. We find out the mid-term status of TIARA-PP and how it is mapping European accelerator education resources.

  8. Accelerating Cosmologies from Compactification

    CERN Document Server

    Townsend, P K; Townsend, Paul K.; Wohlfarth, Mattias N.R.

    2003-01-01

    A solution of the (4+n)-dimensional vacuum Einstein equations is found for which spacetime is compactified on a compact hyperbolic manifold of time-varying volume to a flat four-dimensional FLRW cosmology undergoing accelerated expansion in Einstein conformal frame. This shows that the `no-go' theorem forbidding acceleration in `standard' (time-independent) compactifications of string/M-theory does not apply to `cosmological' (time-dependent) hyperbolic compactifications.

  9. Heat management in integrated circuits on-chip and system-level monitoring and cooling

    CERN Document Server

    Ogrenci-Memik, Seda

    2016-01-01

    This essential overview covers the subject of thermal monitoring and management in integrated circuits. Specifically, it focuses on devices and materials that are intimately integrated on-chip (as opposed to in-package or on-board) for the purposes of thermal monitoring and thermal management.

  10. Deuterium accelerator experiments for APT.

    Energy Technology Data Exchange (ETDEWEB)

    Causey, Rion A. (Sandia National Laboratories, Livermore, CA); Hertz, Kristin L. (Sandia National Laboratories, Livermore, CA); Cowgill, Donald F. (Sandia National Laboratories, Livermore, CA)

    2005-08-01

    Sandia National Laboratories in California initiated an experimental program to determine whether tritium retention in the tube walls and permeation through the tubes into the surrounding coolant water would be a problem for the Accelerator Production of Tritium (APT), and to find ways to mitigate the problem, if it existed. Significant holdup in the tube walls would limit the ability of APT to meet its production goals, and high levels of permeation would require a costly cleanup system for the cooling water. To simulate tritium implantation, a 200 keV accelerator was used to implant deuterium into Al 6061-T and SS3 16L samples at temperatures and particle fluxes appropriate for APT, for times varying between one week and five months. The implanted samples were characterized to determine the deuterium retention and Permeation. During the implantation, the D(d,p)T nuclear reaction was used to monitor the build-up of deuterium in the implant region of the samples. These experiments increased in sophistication, from mono-energetic deuteron implants to multi-energetic deuteron and proton implants, to more accurately reproduce the conditions expected in APT. Micron-thick copper, nickel, and anodized aluminum coatings were applied to the front surface of the samples (inside of the APT walls) in an attempt to lower retention and permeation. The reduction in both retention and permeation produced by the nickel coatings, and the ability to apply them to the inside of the APT tubes, indicate that both nickel-coated Al 6061-T6 and nickel-coated SS3 16L tubes would be effective for use in APT. The results of this work were submitted to the Accelerator Production of Tritium project in document number TPO-E29-Z-TNS-X-00050, APT-MP-01-17.

  11. Biomedical accelerator mass spectrometry

    Science.gov (United States)

    Freeman, Stewart P. H. T.; Vogel, John S.

    1995-05-01

    Ultrasensitive SIMS with accelerator based spectrometers has recently begun to be applied to biomedical problems. Certain very long-lived radioisotopes of very low natural abundances can be used to trace metabolism at environmental dose levels ( [greater-or-equal, slanted] z mol in mg samples). 14C in particular can be employed to label a myriad of compounds. Competing technologies typically require super environmental doses that can perturb the system under investigation, followed by uncertain extrapolation to the low dose regime. 41Ca and 26Al are also used as elemental tracers. Given the sensitivity of the accelerator method, care must be taken to avoid contamination of the mass spectrometer and the apparatus employed in prior sample handling including chemical separation. This infant field comprises the efforts of a dozen accelerator laboratories. The Center for Accelerator Mass Spectrometry has been particularly active. In addition to collaborating with groups further afield, we are researching the kinematics and binding of genotoxins in-house, and we support innovative uses of our capability in the disciplines of chemistry, pharmacology, nutrition and physiology within the University of California. The field can be expected to grow further given the numerous potential applications and the efforts of several groups and companies to integrate more the accelerator technology into biomedical research programs; the development of miniaturized accelerator systems and ion sources capable of interfacing to conventional HPLC and GMC, etc. apparatus for complementary chemical analysis is anticipated for biomedical laboratories.

  12. Accelerators for America's Future

    Science.gov (United States)

    Bai, Mei

    2016-03-01

    Particle accelerator, a powerful tool to energize beams of charged particles to a desired speed and energy, has been the working horse for investigating the fundamental structure of matter and fundermental laws of nature. Most known examples are the 2-mile long Stanford Linear Accelerator at SLAC, the high energy proton and anti-proton collider Tevatron at FermiLab, and Large Hadron Collider that is currently under operation at CERN. During the less than a century development of accelerator science and technology that led to a dazzling list of discoveries, particle accelerators have also found various applications beyond particle and nuclear physics research, and become an indispensible part of the economy. Today, one can find a particle accelerator at almost every corner of our lives, ranging from the x-ray machine at the airport security to radiation diagnostic and therapy in hospitals. This presentation will give a brief introduction of the applications of this powerful tool in fundermental research as well as in industry. Challenges in accelerator science and technology will also be briefly presented

  13. Trend modelling of wave parameters and application in onboard prediction of ship responses

    DEFF Research Database (Denmark)

    Montazeri, Najmeh; Nielsen, Ulrik Dam; Jensen, J. Juncher

    2015-01-01

    This paper presents a trend analysis for prediction of sea state parameters onboard shipsduring voyages. Given those parameters, a JONSWAP model and also the transfer functions, prediction of wave induced ship responses are thus made. The procedure is tested with full-scale data of an in-service ......This paper presents a trend analysis for prediction of sea state parameters onboard shipsduring voyages. Given those parameters, a JONSWAP model and also the transfer functions, prediction of wave induced ship responses are thus made. The procedure is tested with full-scale data of an in...

  14. Diffusive Shock Acceleration and Reconnection Acceleration Processes

    Science.gov (United States)

    Zank, G. P.; Hunana, P.; Mostafavi, P.; Le Roux, J. A.; Li, Gang; Webb, G. M.; Khabarova, O.; Cummings, A.; Stone, E.; Decker, R.

    2015-12-01

    Shock waves, as shown by simulations and observations, can generate high levels of downstream vortical turbulence, including magnetic islands. We consider a combination of diffusive shock acceleration (DSA) and downstream magnetic-island-reconnection-related processes as an energization mechanism for charged particles. Observations of electron and ion distributions downstream of interplanetary shocks and the heliospheric termination shock (HTS) are frequently inconsistent with the predictions of classical DSA. We utilize a recently developed transport theory for charged particles propagating diffusively in a turbulent region filled with contracting and reconnecting plasmoids and small-scale current sheets. Particle energization associated with the anti-reconnection electric field, a consequence of magnetic island merging, and magnetic island contraction, are considered. For the former only, we find that (i) the spectrum is a hard power law in particle speed, and (ii) the downstream solution is constant. For downstream plasmoid contraction only, (i) the accelerated spectrum is a hard power law in particle speed; (ii) the particle intensity for a given energy peaks downstream of the shock, and the distance to the peak location increases with increasing particle energy, and (iii) the particle intensity amplification for a particular particle energy, f(x,c/{c}0)/f(0,c/{c}0), is not 1, as predicted by DSA, but increases with increasing particle energy. The general solution combines both the reconnection-induced electric field and plasmoid contraction. The observed energetic particle intensity profile observed by Voyager 2 downstream of the HTS appears to support a particle acceleration mechanism that combines both DSA and magnetic-island-reconnection-related processes.

  15. Background simulations for the Large Area Detector onboard LOFT

    DEFF Research Database (Denmark)

    Campana, Riccardo; Feroci, Marco; Ettore, Del Monte

    2013-01-01

    is essential to assess the scientific performance of the mission and optimize the design of its main instrument, the Large Area Detector (LAD). In this paper the results of an extensive Geant-4 simulation of the instrumentwillbe discussed, showing the main contributions to the background and the design...... solutions for its reduction and control. Our results show that the current LOFT/LAD design is expected to meet its scientific requirement of a background rate equivalent to 10 mCrab in 2aEuro'30 keV, achieving about 5 mCrab in the most important 2-10 keV energy band. Moreover, simulations show...... an anticipated modulation of the background rate as small as 10 % over the orbital timescale. The intrinsic photonic origin of the largest background component also allows for an efficient modelling, supported by an in-flight active monitoring, allowing to predict systematic residuals significantly better than...

  16. Outline of SCM data processing system onboard ETS-5

    Science.gov (United States)

    Matsuda, Sumio; Tamura, Takashi; Uesugi, Masato

    1992-08-01

    An overview of the operation of the Solar Cell Monitor (SCM) is presented. In minicomputer, SCM data are extracted from the telemetry data, data distribution at 17:00 (Japan Standard Time) plus or minus 15 minutes when the SCM entrance surface directly faces to the sun were obtained, SCM data sent in hexadecimal number system were engineeringly converted to analog values, and the results are recorded in each solar cell file. The data processed by mini computer are sent to personal computer through in site telephone circuit, and the data undergo the following three compensations: (1) for solar ray intensity variation due to the elliptic earth revolution orbit; (2) for the seasonal variation of angles between SCM entrance surface and the sun caused by the inclination of the earth's axis; and (3) for seasonal SCM temperature variation.

  17. Robonaut 2 - IVA Experiments On-Board ISS and Development Towards EVA Capability

    Science.gov (United States)

    Diftler, Myron; Hulse, Aaron; Badger, Julia; Thackston, Allison; Rogers, Jonathan

    2014-01-01

    prohibitively low. The upgraded R2 control and safety systems solve this problem using momentum limiting, momentum control, and kinetic energy minimization. Momentum and kinetic energy take the robot mass into account relieving low velocity restrictions on low inertia end-effectors while ensuring that the overall mass of R2 is limited from hazardous velocities. The momentum of R2's five safety nodes (each of the four end-effectors and the body) is monitored and compared to a single momentum limit. If any of the five nodes exceeds the safety limit, the motor power is removed and the robot comes to a stop. Momentum control/limiting also provides a simple, reliable method to integrate hand held tools into the safety system by providing the tool mass to the control system thus automatically reducing the allowable velocity of the end-effector with the tool. Work on the ground continues to build the skill set for an EVA Robonaut. Recent experiments (Figure 2) demonstrate how a teleoperator can use R2 to manipulate a tether hook, an important safety precaution on spacewalks. Another task displayed Robonaut's ability to pull back a protective jacket over a hose and search for damage, as well as inspect a quick-disconnect fitting for debris. Demonstrations such as these are indicative of EVA work done on ISS, specifically seen during a series of spacewalks over 2012 and 2013 where astronauts searched for an ammonia leak in one of the external cooling loops. Through experiments both on ISS and on the ground, R2 is evolving and providing the information needed to plan out the upgrades that will make an EVA Robonaut an effective tool. With the addition of legs, R2 will start climbing inside the space station and supply invaluable information on how the climbing strategies and task stabilization techniques must be refined. Ground R2 systems will continue to work with additional EVA tools and equipment in preparation for onboard IVA testing and future EVA applications.

  18. Integrated electronic system for ultrasonic structural health monitoring

    OpenAIRE

    Ruiz González, Mariano; Monje, Pedro María; Casado, Luciano; Aranguren, Gerardo; Cokonaj, Valerijan; Barrera Lopez de Turiso, Eduardo

    2012-01-01

    A fully integrated on-board electronic system that can perform in-situ structural health monitoring (SHM) of aircraft?s structures using specifically designed equipment for SHM based on guided wave ultrasonic method or Lamb waves? method is introduced. This equipment is called Phased Array Monitoring for Enhanced Life Assessment (PAMELA III) and is an essential part of overall PAMELA SHM? system. PAMELA III can generate any kind of excitation signals, acquire the response signals that propaga...

  19. Small type accelerator. Try for accelerator driven system

    CERN Document Server

    Mori, Y

    2003-01-01

    FFAG (Fixed-field alternating gradient) accelerator for accelerator driven subcritical reactor, which aims to change from long-lived radioactive waste to short-lived radioactivity, is introduced. It is ring accelerator. The performance needed is proton as accelerator particle, 10MW (total) beam power, about 1GeV beam energy, >30% power efficiency and continuous beam. The feature of FFAG accelerator is constant magnetic field. PoP (Proof-of-principle)-FFAG accelerator, radial type, was run at first in Japan in 2000. The excursion is about some ten cm. In principle, beam can be injected and extracted at any place of ring. The 'multi-fish' acceleration can accelerate beams to 100% duty by repeating acceleration. 150MeV-FFAG accelerator has been started since 2001. It tried to practical use, for example, treatment of cancer. (S.Y.)

  20. Onboard Determination of Vehicle Glide Capability for Shuttle Abort Flight Managment (SAFM)

    Science.gov (United States)

    Straube, Timothy; Jackson, Mark; Fill, Thomas; Nemeth, Scott

    2002-01-01

    When one or more main engines fail during ascent, the flight crew of the Space Shuttle must make several critical decisions and accurately perform a series of abort procedures. One of the most important decisions for many aborts is the selection ofa landing site. Several factors influence the ability to reach a landing site, including the spacecraft point of atmospheric entry, the energy state at atmospheric entry, the vehicle glide capability from that energy state, and whether one or more suitable landing sites are within the glide capability. Energy assessment is further complicated by the fact that phugoid oscillations in total energy influence glide capability. Once the glide capability is known, the crew must select the "best" site option based upon glide capability and landing site conditions and facilities. Since most of these factors cannot currently be assessed by the crew in flight, extensive planning is required prior to each mission to script a variety of procedures based upon spacecraft velocity at the point of engine failure (or failures). The results of this preflight planning are expressed in tables and diagrams on mission-specific cockpit checklists. Crew checklist procedures involve leafing through several pages of instructions and navigating a decision tree for site selection and flight procedures - all during a time critical abort situation. With the advent of the Cockpit Avionics Upgrade (CAU), the Shuttle will have increased on-board computational power to help alleviate crew workload during aborts and provide valuable situational awareness during nominal operations. One application baselined for the CAU computers is Shuttle Abort Flight Management (SAFM), whose requirements have been designed and prototyped. The SAFM application includes powered and glided flight algorithms. This paper describes the glided flight algorithm which is dispatched by SAFM to determine the vehicle glide capability and make recommendations to the crew for site

  1. Updates on the background estimates for the X-IFU instrument onboard of the ATHENA mission

    Science.gov (United States)

    Lotti, S.; Macculi, C.; D'Andrea, M.; Piro, L.; Molendi, S.; Gastaldello, F.; Mineo, T.; D'ai, A.; Bulgarelli, A.; Fioretti, V.; Jacquey, C.; Laurenza, M.; Laurent, P.

    2016-07-01

    ATHENA is the second large mission in ESA Cosmic Vision 2015-2025, with a launch foreseen in 2028 towards the L2 orbit. The mission addresses the science theme "The Hot and Energetic Universe", by coupling a high-performance X-ray Telescope with two complementary focal-plane instruments. One of these, the X-ray Integral Field Unit (X-IFU) is a TES based kilo-pixel array, providing spatially resolved high-resolution spectroscopy (2.5 eV at 6 keV) over a 5 arcmin FoV. The background for this kind of detectors accounts for several components: the diffuse Cosmic Xray Background, the low energy particles ( 100 MeV) crossing the spacecraft and reaching the focal plane from every direction. In particular, these high energy particles lose energy in the materials they cross, creating secondaries along their path that can induce an additional background component. Each one of these components is under study of a team dedicated to the background issues regarding the X-IFU, with the aim to reduce their impact on the instrumental performances. This task is particularly challenging, given the lack of data on the background of X-ray detectors in L2, the uncertainties on the particle environment to be expected in such orbit, and the reliability of the models used in the Monte Carlo background computations. As a consequence, the activities addressed by the group range from the reanalysis of the data of previous missions like XMMNewton, to the characterization of the L2 environment by data analysis of the particle monitors onboard of satellites present in the Earth magnetotail, to the characterization of solar events and their occurrence, and to the validation of the physical models involved in the Monte Carlo simulations. All these activities will allow to develop a set of reliable simulations to predict, analyze and find effective solutions to reduce the particle background experienced by the X-IFU, ultimately satisfying the scientific requirement that enables the science of

  2. Airborne concentrations of asbestos onboard maritime shipping vessels (1978-1992).

    Science.gov (United States)

    Murbach, Dana M; Madl, Amy K; Unice, Ken M; Knutsen, Jeffrey S; Chapman, Pamela S; Brown, Jay L; Paustenbach, Dennis J

    2008-06-01

    The exposure of shipyard workers to asbestos has been frequently investigated during the installation, repair or removal of asbestos insulation. The same level of attention, however, has not been directed to asbestos exposure of maritime seamen or sailors. In this paper, we assemble and analyze historical industrial hygiene (IH) data quantifying airborne asbestos concentrations onboard maritime shipping vessels between 1978 and 1992. Air monitoring and bulk sampling data were compiled from 52 IH surveys conducted on 84 different vessels, including oil tankers and cargo vessels, that were docked and/or at sea, but these were not collected during times when there was interaction with asbestos-containing materials (ACMs). One thousand and eighteen area air samples, 20 personal air samples and 24 air samples of unknown origin were analyzed by phase contrast microscopy (PCM); 19 area samples and six samples of unknown origin were analyzed by transmission electron microscopy (TEM) and 13 area air samples were analyzed by scanning electron microscopy (SEM). In addition, 482 bulk samples were collected from suspected ACMs, including insulation, ceiling panels, floor tiles, valve packing and gaskets. Fifty-three percent of all PCM and 4% of all TEM samples were above their respective detection limits. The average airborne concentration for the PCM area samples (n = 1018) was 0.008 fibers per cubic centimeter (f cc(-1)) (95th percentile of 0.040 f cc(-1)). Air concentrations in the living and recreational areas of the vessels (e.g. crew quarters, common rooms) averaged 0.004 f cc(-1) (95th percentile of 0.014 f cc(-1)), while air concentrations in the engine rooms and machine shops averaged 0.010 f cc(-1) (95th percentile of 0.068 f cc(-1)). Airborne asbestos concentrations were also classified by vessel type (cargo, tanker or Great Lakes), transport status (docked or underway on active voyage) and confirmed presence of ACM. Approximately 1.3 and 0% of the 1018 area samples

  3. Process for Upgrading Cognitive Assessment Capabilities Onboard the International Space Station

    Science.gov (United States)

    Picano, J. J.; Seaton, K. A.; Holland, A. W.

    2016-01-01

    MOTIVATION: Spaceflight poses varied and unique risks to the brain and cognitive functioning including radiation exposure, sleep disturbance, fatigue, fluid shifts (increased intracranial pressure), toxin exposure, elevated carbon dioxide, and traumatic brain injury, among others. These potential threats to cognitive functioning are capable of degrading performance and compromising mission success. Furthermore, the threats may increase in severity, and new types of threats may emerge for longer duration exploration missions. This presentation will describe the process used to identify gaps in our current approach, evaluate best practices in cognitive assessment, and transition new cognitive assessment tools to operational use. OVERVIEW: Risks to brain health and performance posed by spaceflight missions require sensitive tools to assess cognitive functioning of astronauts in flight. The Spaceflight Cognitive Assessment Tool for Windows (WinSCAT) is the automated cognitive assessment tool currently deployed onboard the International Space Station (ISS). WinSCAT provides astronauts and flight surgeons with objective data to monitor neurocognitive functioning. WinSCAT assesses 5 discrete cognitive domains, is sensitive to changes in cognitive functioning, and was designed to be completed in less than 15 minutes. However, WinSCAT does not probe other areas of cognitive functioning that might be important to mission success. Researchers recently have developed batteries that may expand current capabilities, such as increased sensitivity to subtle fluctuations in cognitive functioning. Therefore, we engaged in a systematic process review in order to improve upon our current capabilities and incorporate new advances in cognitive assessment. This process included a literature review on newer measures of neurocognitive assessment, surveys of operational flight surgeons at NASA regarding needs and gaps in our capabilities, and expert panel review of candidate cognitive

  4. Flow accelerated organic coating degradation

    Science.gov (United States)

    Zhou, Qixin

    Applying organic coatings is a common and the most cost effective way to protect metallic objects and structures from corrosion. Water entry into coating-metal interface is usually the main cause for the deterioration of organic coatings, which leads to coating delamination and underfilm corrosion. Recently, flowing fluids over sample surface have received attention due to their capability to accelerate material degradation. A plethora of works has focused on the flow induced metal corrosion, while few studies have investigated the flow accelerated organic coating degradation. Flowing fluids above coating surface affect corrosion by enhancing the water transport and abrading the surface due to fluid shear. Hence, it is of great importance to understand the influence of flowing fluids on the degradation of corrosion protective organic coatings. In this study, a pigmented marine coating and several clear coatings were exposed to the laminar flow and stationary immersion. The laminar flow was pressure driven and confined in a flow channel. A 3.5 wt% sodium chloride solution and pure water was employed as the working fluid with a variety of flow rates. The corrosion protective properties of organic coatings were monitored inline by Electrochemical Impedance Spectroscopy (EIS) measurement. Equivalent circuit models were employed to interpret the EIS spectra. The time evolution of coating resistance and capacitance obtained from the model was studied to demonstrate the coating degradation. Thickness, gloss, and other topography characterizations were conducted to facilitate the assessment of the corrosion. The working fluids were characterized by Fourier Transform Infrared Spectrometer (FTIR) and conductivity measurement. The influence of flow rate, fluid shear, fluid composition, and other effects in the coating degradation were investigated. We conclude that flowing fluid on the coating surface accelerates the transport of water, oxygen, and ions into the coating, as

  5. WE-G-17A-01: Improving Tracking Image Spatial Resolution for Onboard MR Image Guided Radiation Therapy Using the WHISKEE Technique

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Y; Mutic, S; Du, D; Green, O [Washington University School of Medicine, Saint Louis, MO (United States); Zeng, Q; Nana, R; Patrick, J; Shvartsman, S; Dempsey, J [ViewRay Incorporated, Oakwood Village, OH (United States)

    2014-06-15

    Purpose: To evaluate the feasibility of using the weighted hybrid iterative spiral k-space encoded estimation (WHISKEE) technique to improve spatial resolution of tracking images for onboard MR image guided radiation therapy (MR-IGRT). Methods: MR tracking images of abdomen and pelvis had been acquired from healthy volunteers using the ViewRay onboard MRIGRT system (ViewRay Inc. Oakwood Village, OH) at a spatial resolution of 2.0mm*2.0mm*5.0mm. The tracking MR images were acquired using the TrueFISP sequence. The temporal resolution had to be traded off to 2 frames per second (FPS) to achieve the 2.0mm in-plane spatial resolution. All MR images were imported into the MATLAB software. K-space data were synthesized through the Fourier Transform of the MR images. A mask was created to selected k-space points that corresponded to the under-sampled spiral k-space trajectory with an acceleration (or undersampling) factor of 3. The mask was applied to the fully sampled k-space data to synthesize the undersampled k-space data. The WHISKEE method was applied to the synthesized undersampled k-space data to reconstructed tracking MR images at 6 FPS. As a comparison, the undersampled k-space data were also reconstructed using the zero-padding technique. The reconstructed images were compared to the original image. The relatively reconstruction error was evaluated using the percentage of the norm of the differential image over the norm of the original image. Results: Compared to the zero-padding technique, the WHISKEE method was able to reconstruct MR images with better image quality. It significantly reduced the relative reconstruction error from 39.5% to 3.1% for the pelvis image and from 41.5% to 4.6% for the abdomen image at an acceleration factor of 3. Conclusion: We demonstrated that it was possible to use the WHISKEE method to expedite MR image acquisition for onboard MR-IGRT systems to achieve good spatial and temporal resolutions simultaneously. Y. Hu and O. green

  6. Dielectric laser accelerators

    Science.gov (United States)

    England, R. Joel; Noble, Robert J.; Bane, Karl; Dowell, David H.; Ng, Cho-Kuen; Spencer, James E.; Tantawi, Sami; Wu, Ziran; Byer, Robert L.; Peralta, Edgar; Soong, Ken; Chang, Chia-Ming; Montazeri, Behnam; Wolf, Stephen J.; Cowan, Benjamin; Dawson, Jay; Gai, Wei; Hommelhoff, Peter; Huang, Yen-Chieh; Jing, Chunguang; McGuinness, Christopher; Palmer, Robert B.; Naranjo, Brian; Rosenzweig, James; Travish, Gil; Mizrahi, Amit; Schachter, Levi; Sears, Christopher; Werner, Gregory R.; Yoder, Rodney B.

    2014-10-01

    The use of infrared lasers to power optical-scale lithographically fabricated particle accelerators is a developing area of research that has garnered increasing interest in recent years. The physics and technology of this approach is reviewed, which is referred to as dielectric laser acceleration (DLA). In the DLA scheme operating at typical laser pulse lengths of 0.1 to 1 ps, the laser damage fluences for robust dielectric materials correspond to peak surface electric fields in the GV /m regime. The corresponding accelerating field enhancement represents a potential reduction in active length of the accelerator between 1 and 2 orders of magnitude. Power sources for DLA-based accelerators (lasers) are less costly than microwave sources (klystrons) for equivalent average power levels due to wider availability and private sector investment. Because of the high laser-to-particle coupling efficiency, required pulse energies are consistent with tabletop microJoule class lasers. Combined with the very high (MHz) repetition rates these lasers can provide, the DLA approach appears promising for a variety of applications, including future high-energy physics colliders, compact light sources, and portable medical scanners and radiative therapy machines.

  7. Autonomous Payload Operations Onboard the International Space Station

    Science.gov (United States)

    Stetson, Howard K.; Deitsch, David K.; Cruzen, Craig A.; Haddock, Angie T.

    2007-01-01

    Operating the International Space Station (ISS) involves many complex crew tended, ground operated and combined systems. Over the life of the ISS program, it has become evident that by having automated and autonomous systems on board, more can be accomplished and at the same time reduce the workload of the crew and ground operators. Engineers at the National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center in Huntsville Alabama, working in collaboration with The Charles Stark Draper Laboratory have developed an autonomous software system that uses the Timeliner User Interface Language and expert logic to continuously monitor ISS payload systems, issue commands and signal ground operators as required. This paper describes the development history of the system, its concept of operation and components. The paper also discusses the testing process as well as the facilities used to develop the system. The paper concludes with a description of future enhancement plans for use on the ISS as well as potential applications to Lunar and Mars exploration systems.

  8. Plasma-based accelerator structures

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Carl B. [Univ. of California, Berkeley, CA (United States)

    1999-12-01

    Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas.

  9. Uniform Acceleration in General Relativity

    CERN Document Server

    Friedman, Yaakov

    2016-01-01

    We extend de la Fuente and Romero's defining equation for uniform acceleration in a general curved spacetime from linear acceleration to the full Lorentz covariant uniform acceleration. In a flat spacetime background, we have explicit solutions. We use generalized Fermi-Walker transport to parallel transport the Frenet basis along the trajectory. In flat spacetime, we obtain velocity and acceleration transformations from a uniformly accelerated system to an inertial system. We obtain the time dilation between accelerated clocks. We apply our acceleration transformations to the motion of a charged particle in a constant electromagnetic field and recover the Lorentz-Abraham-Dirac equation.

  10. Cosmic Plasma Wakefield Acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Chen, P

    2004-04-26

    Recently we proposed a new cosmic acceleration mechanism which was based on the wakefields excited by the Alfven shocks in a relativistically owing plasma. In this paper we include some omitted details, and show that there exists a threshold condition for transparency below which the accelerating particle is collision-free and suffers little energy loss in the plasma medium. The stochastic encounters of the random accelerating-decelerating phases results in a power-law energy spectrum: f({epsilon}) {proportional_to} 1/{epsilon}{sup 2}. As an example, we discuss the possible production of super-GZK ultra high energy cosmic rays (UHECR) in the atmosphere of gamma ray bursts. The estimated event rate in our model agrees with that from UHECR observations.

  11. Superconducting Accelerator Magnets

    CERN Document Server

    Mess, K H; Wolff, S

    1996-01-01

    The main topic of the book are the superconducting dipole and quadrupole magnets needed in high-energy accelerators and storage rings for protons, antiprotons or heavy ions. The basic principles of low-temperature superconductivity are outlined with special emphasis on the effects which are relevant for accelerator magnets. Properties and fabrication methods of practical superconductors are described. Analytical methods for field calculation and multipole expansion are presented for coils without and with iron yoke. The effect of yoke saturation and geometric distortions on field quality is studied. Persistent magnetization currents in the superconductor and eddy currents the copper part of the cable are analyzed in detail and their influence on field quality and magnet performance is investigated. Superconductor stability, quench origins and propagation and magnet protection are addressed. Some important concepts of accelerator physics are introduced which are needed to appreciate the demanding requirements ...

  12. Particle accelerator physics

    CERN Document Server

    Wiedemann, Helmut

    2007-01-01

    Particle Accelerator Physics is an in-depth and comprehensive introduction to the field of high-energy particle acceleration and beam dynamics. Part I gathers the basic tools, recalling the essentials of electrostatics and electrodynamics as well as of particle dynamics in electromagnetic fields. Part II is an extensive primer in beam dynamics, followed in Part III by the introduction and description of the main beam parameters. Part IV is devoted to the treatment of perturbations in beam dynamics. Part V discusses the details of charged particle accleration. Part VI and Part VII introduce the more advanced topics of coupled beam dynamics and the description of very intense beams. Part VIII is an exhaustive treatment of radiation from accelerated charges and introduces important sources of coherent radiation such as synchrotrons and free-electron lasers. Part IX collects the appendices gathering useful mathematical and physical formulae, parameters and units. Solutions to many end-of-chapter problems are give...

  13. On-board conversion of methanol to dimethyl ether as an alternative diesel fuel

    Energy Technology Data Exchange (ETDEWEB)

    Armbruster, H.; Heinzelmann, G.; Struis, R.; Stucki, S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    The catalytic dehydration of methanol to dimethyl ether was investigated for application on-board a methanol fuelled vehicle. Several catalysts have been tested in a fixed bed reactor. Our approach is to develop a small and efficient reactor converting liquid MeOH under pressure and at low reaction temperatures. (author) 2 figs., 5 refs.

  14. Data systems and computer science space data systems: Onboard networking and testbeds

    Science.gov (United States)

    Dalton, Dan

    1991-01-01

    The technical objectives are to develop high-performance, space-qualifiable, onboard computing, storage, and networking technologies. The topics are presented in viewgraph form and include the following: justification; technology challenges; program description; and state-of-the-art assessment.

  15. The CFRP primary structure of the MIRI instrument onboard the James Webb Space Telescope

    DEFF Research Database (Denmark)

    Jessen, Niels Christian; Nørgaard-Nielsen, Hans Ulrik; Schroll, J

    2004-01-01

    The design of the Primary Structure of the Mid Infra-Red Instrument (MIRI) onboard the NASA/ESA James Webb Space Telescope will be presented. The main design driver is the energy flow from the 35 K "hot" satellite interface to the 7 K "cold" MIRI interface. Carbon fibre reinforced plastic (CFRP...

  16. Processor breadboard for on-board RFI detection and mitigation in MetOp-SG radiometers

    DEFF Research Database (Denmark)

    Skou, Niels; Kristensen, Steen S.; Kovanen, Arhippa;

    2015-01-01

    that the next generation MetOp satellites must include some kind of RFI detection and mitigation system at Ku band. This paper describes a breadboard processor that detects and mitigates RFI on-board the satellite. Thus cleaned data can be generated in real time, and following suitable integration, downloaded...

  17. Onboard centralized frame tree database for intelligent space operations of the Mars Science Laboratory Rover.

    Science.gov (United States)

    Kim, Won S; Diaz-Calderon, Antonio; Peters, Stephen F; Carsten, Joseph L; Leger, Chris

    2014-11-01

    Planetary surface science operations performed by robotic space systems frequently require pointing cameras at various objects and moving a robotic arm end effector tool toward specific targets. Earlier NASA Mars Exploration Rovers did not have the ability to compute actual coordinates for given object coordinate frame names and had to be provided with explicit coordinates. Since it sometimes takes hours to more than a day to get final approval of certain calculated coordinates for command uplink via the Earth-based mission operations procedures, a highly desired enhancement for future rovers was to have the onboard automated capability to compute the coordinates for a given frame name. The Mars Science Laboratory (MSL) rover mission is the first to have a centralized coordinate transform database to maintain the knowledge of spatial relations. This onboard intelligence significantly simplifies communication and control between Earth-based human mission operators and the robotic rover on Mars by supporting higher level abstraction of commands using object and target names instead of coordinates. More specifically, the spatial relations of many object frames are represented hierarchically in a tree data structure, called the frame tree. Individual frame transforms are populated by their respective modules that have specific knowledge of the frames. Through this onboard centralized frame tree database, client modules can query transforms between any two frames and support spacecraft commands that use any frames maintained in the frame tree. Various operational examples in the MSL mission that have greatly benefitted from this onboard centralized frame tree database are presented.

  18. Onboard Interferometric SAR Processor for the Ka-Band Radar Interferometer (KaRIn)

    Science.gov (United States)

    Esteban-Fernandez, Daniel; Rodriquez, Ernesto; Peral, Eva; Clark, Duane I.; Wu, Xiaoqing

    2011-01-01

    An interferometric synthetic aperture radar (SAR) onboard processor concept and algorithm has been developed for the Ka-band radar interferometer (KaRIn) instrument on the Surface and Ocean Topography (SWOT) mission. This is a mission- critical subsystem that will perform interferometric SAR processing and multi-look averaging over the oceans to decrease the data rate by three orders of magnitude, and therefore enable the downlink of the radar data to the ground. The onboard processor performs demodulation, range compression, coregistration, and re-sampling, and forms nine azimuth squinted beams. For each of them, an interferogram is generated, including common-band spectral filtering to improve correlation, followed by averaging to the final 1 1-km ground resolution pixel. The onboard processor has been prototyped on a custom FPGA-based cPCI board, which will be part of the radar s digital subsystem. The level of complexity of this technology, dictated by the implementation of interferometric SAR processing at high resolution, the extremely tight level of accuracy required, and its implementation on FPGAs are unprecedented at the time of this reporting for an onboard processor for flight applications.

  19. [Validation of HJ-1B thermal infrared channels onboard radiometric calibration based on spectral response differences].

    Science.gov (United States)

    Liu, Li; Fu, Qiao-yan; Shi, Ting-ting; Wang, Ai-chun; Zhang, Xue-wen

    2014-08-01

    Since HJ-1B was launched, 7 sets of blackbody data have been used to calculate onboard calibration coefficients, but the research work on the validation of coefficients is rare. According to the onboard calibration principle, calibration coefficients of HJ-1B thermal infrared channel on Sep 14th, 2009 were calculated with the half-width, moments and look-up table methods. MODIS was selected for the reference sensor, and algorithms of spectral match were improved between the HJ-1B thermal infrared channel and MODIS 31, 32 channels based on the spectral response divergence. The relationship of top of atmosphere (TOA) radiance between the remote sensors was calculated, based on which the surface leaving brightness temperature was calculated by Planck function to validate the brightness temperature calculated through the onboard calibration coefficients. The equivalent brightness temperature calculated by spectral response divergence method is 285.97 K, and the inversion brightness temperature calculated by half-width, moments and look-up table methods is 288.77, 274.52 and 285.97 K respectively. The difference between the inversion brightness temperature and the equivalent brightness temperature is 2.8, -11.46 and 0.02 K, respectively, which demonstrate that onboard calibration coefficients calculated by the look-up table method has better precision and feasibility.

  20. The Application of a Mixed General/Special Purpose Hardware in On-Board SATSAT Processing

    NARCIS (Netherlands)

    Bierens, L.H.J.

    1998-01-01

    In SATSAR huge amounts of data are involved corresponding to data rates of 100 to 1000 Mbits/s. The communication system and the intermediate storage on-board the satellite must handle this increasing amount of data as well. Furthermore, ground stations must process, broadcast and archive the SAR da