Investigations of Low Temperature Time Dependent Cracking

Energy Technology Data Exchange (ETDEWEB)

Van der Sluys, W A; Robitz, E S; Young, B A; Bloom, J

2002-09-30

The objective of this project was to investigate metallurgical and mechanical phenomena associated with time dependent cracking of cold bent carbon steel piping at temperatures between 327 C and 360 C. Boiler piping failures have demonstrated that understanding the fundamental metallurgical and mechanical parameters controlling these failures is insufficient to eliminate it from the field. The results of the project consisted of the development of a testing methodology to reproduce low temperature time dependent cracking in laboratory specimens. This methodology was used to evaluate the cracking resistance of candidate heats in order to identify the factors that enhance cracking sensitivity. The resultant data was integrated into current available life prediction tools.

Real-time transmission electron microscope observation of gold nanoclusters diffusing into silicon at room temperature

International Nuclear Information System (INIS)

Ishida, Tadashi; Nakajima, Yuuki; Fujita, Hiroyuki; Endo, Junji; Collard, Dominique

2009-01-01

Gold diffusion into silicon at room temperature was observed in real time with atomic resolution. Gold nanoclusters were formed on a silicon surface by an electrical discharge between a silicon tip and a gold coated tip inside an ultrahigh-vacuum transmission electron microscope (TEM) specimen chamber. At the moment of the gold nanocluster deposition, the gold nanoclusters had a crystalline structure. The crystalline structure gradually disappeared due to the interdiffusion between silicon and gold as observed after the deposition of gold nanoclusters. The shape of the nanocluster gradually changed due to the gold diffusion into the damaged silicon. The diffusion front between silicon and gold moved toward the silicon side. From the observations of the diffusion front, the gold diffusivity at room temperature was extracted. The extracted activation energy, 0.21 eV, matched the activation energy in bulk diffusion between damaged silicon and gold. This information is useful for optimizing the hybridization between solid-state and biological nanodevices in which gold is used as an adhesive layer between the two devices.

Real-time temperature field measurement based on acoustic tomography

International Nuclear Information System (INIS)

Bao, Yong; Jia, Jiabin; Polydorides, Nick

2017-01-01

Acoustic tomography can be used to measure the temperature field from the time-of-flight (TOF). In order to capture real-time temperature field changes and accurately yield quantitative temperature images, two improvements to the conventional acoustic tomography system are studied: simultaneous acoustic transmission and TOF collection along multiple ray paths, and an offline iteration reconstruction algorithm. During system operation, all the acoustic transceivers send modulated and filtered wideband Kasami sequences simultaneously to facilitate fast and accurate TOF measurements using cross-correlation detection. For image reconstruction, the iteration process is separated and executed offline beforehand to shorten computation time for online temperature field reconstruction. The feasibility and effectiveness of the developed methods are validated in the simulation study. The simulation results demonstrate that the proposed method can reduce the processing time per frame from 160 ms to 20 ms, while the reconstruction error remains less than 5%. Hence, the proposed method has great potential in the measurement of rapid temperature change with good temporal and spatial resolution. (paper)

In Situ TEM Multi-Beam Ion Irradiation as a Technique for Elucidating Synergistic Radiation Effects

Energy Technology Data Exchange (ETDEWEB)

Taylor, Caitlin; Bufford, Daniel; Muntifering, Brittany; Senor, David; Steckbeck, Mackenzie; Davis, Justin; Doyle, Barney; Buller, Daniel; Hattar, Khalid

2017-09-29

Materials designed for nuclear reactors undergo microstructural changes resulting from a combination of several environmental factors, including neutron irradiation damage, gas accumulation and elevated temperatures. Typical ion beam irradiation experiments designed for simulating a neutron irradiation environment involve irradiating the sample with a single ion beam and subsequent characterization of the resulting microstructure, often by transmission electron microscopy (TEM). This method does not allow for examination of microstructural effects due to simultaneous gas accumulation and displacement cascade damage, which occurs in a reactor. Sandia’s in situ ion irradiation TEM (I3TEM) offers the unique ability to observe microstructural changes due to irradiation damage caused by concurrent multi-beam ion irradiation in real time. This allows for time-dependent microstructure analysis. A plethora of additional in situ stages can be coupled with these experiments, e.g., for more accurately simulating defect kinetics at elevated reactor temperatures. This work outlines experiments showing synergistic effects in Au using in situ ion irradiation with various combinations of helium, deuterium and Au ions, as well as some initial work on materials utilized in tritium-producing burnable absorber rods (TPBARs): zirconium alloys and LiAlO2.

In Situ TEM Multi-Beam Ion Irradiation as a Technique for Elucidating Synergistic Radiation Effects

Directory of Open Access Journals (Sweden)

Caitlin Anne Taylor

2017-09-01

Full Text Available Materials designed for nuclear reactors undergo microstructural changes resulting from a combination of several environmental factors, including neutron irradiation damage, gas accumulation and elevated temperatures. Typical ion beam irradiation experiments designed for simulating a neutron irradiation environment involve irradiating the sample with a single ion beam and subsequent characterization of the resulting microstructure, often by transmission electron microscopy (TEM. This method does not allow for examination of microstructural effects due to simultaneous gas accumulation and displacement cascade damage, which occurs in a reactor. Sandia’s in situ ion irradiation TEM (I3TEM offers the unique ability to observe microstructural changes due to irradiation damage caused by concurrent multi-beam ion irradiation in real time. This allows for time-dependent microstructure analysis. A plethora of additional in situ stages can be coupled with these experiments, e.g., for more accurately simulating defect kinetics at elevated reactor temperatures. This work outlines experiments showing synergistic effects in Au using in situ ion irradiation with various combinations of helium, deuterium and Au ions, as well as some initial work on materials utilized in tritium-producing burnable absorber rods (TPBARs: zirconium alloys and LiAlO2.

Optimized effective potential in real time: Problems and prospects in time-dependent density-functional theory

International Nuclear Information System (INIS)

Mundt, Michael; Kuemmel, Stephan

2006-01-01

The integral equation for the time-dependent optimized effective potential (TDOEP) in time-dependent density-functional theory is transformed into a set of partial-differential equations. These equations only involve occupied Kohn-Sham orbitals and orbital shifts resulting from the difference between the exchange-correlation potential and the orbital-dependent potential. Due to the success of an analog scheme in the static case, a scheme that propagates orbitals and orbital shifts in real time is a natural candidate for an exact solution of the TDOEP equation. We investigate the numerical stability of such a scheme. An approximation beyond the Krieger-Li-Iafrate approximation for the time-dependent exchange-correlation potential is analyzed

Time dependent semiclassical tunneling through one dimensional barriers using only real valued trajectories

International Nuclear Information System (INIS)

Herman, Michael F.

2015-01-01

The time independent semiclassical treatment of barrier tunneling has been understood for a very long time. Several semiclassical approaches to time dependent tunneling through barriers have also been presented. These typically involve trajectories for which the position variable is a complex function of time. In this paper, a method is presented that uses only real valued trajectories, thus avoiding the complications that can arise when complex trajectories are employed. This is accomplished by expressing the time dependent wave packet as an integration over momentum. The action function in the exponent in this expression is expanded to second order in the momentum. The expansion is around the momentum, p 0 * , at which the derivative of the real part of the action is zero. The resulting Gaussian integral is then taken. The stationary phase approximation requires that the derivative of the full action is zero at the expansion point, and this leads to a complex initial momentum and complex tunneling trajectories. The “pseudo-stationary phase” approximation employed in this work results in real values for the initial momentum and real valued trajectories. The transmission probabilities obtained are found to be in good agreement with exact quantum results

Time dependent semiclassical tunneling through one dimensional barriers using only real valued trajectories

Energy Technology Data Exchange (ETDEWEB)

Herman, Michael F. [Department of Chemistry, Tulane University, New Orleans, Louisiana 70118 (United States)

2015-10-28

The time independent semiclassical treatment of barrier tunneling has been understood for a very long time. Several semiclassical approaches to time dependent tunneling through barriers have also been presented. These typically involve trajectories for which the position variable is a complex function of time. In this paper, a method is presented that uses only real valued trajectories, thus avoiding the complications that can arise when complex trajectories are employed. This is accomplished by expressing the time dependent wave packet as an integration over momentum. The action function in the exponent in this expression is expanded to second order in the momentum. The expansion is around the momentum, p{sub 0{sup *}}, at which the derivative of the real part of the action is zero. The resulting Gaussian integral is then taken. The stationary phase approximation requires that the derivative of the full action is zero at the expansion point, and this leads to a complex initial momentum and complex tunneling trajectories. The “pseudo-stationary phase” approximation employed in this work results in real values for the initial momentum and real valued trajectories. The transmission probabilities obtained are found to be in good agreement with exact quantum results.

Relation between Euclidean and real time calculations of Green functions at finite temperature

International Nuclear Information System (INIS)

Bochkarev, A.

1993-01-01

We find a relation between the semiclassical approximation of the temperature (Matsubara) two-point correlator and the corresponding classical Green function in real time at finite temperature. The anharmonic oscillator at finite temperature is used to illustrate our statement, which is however of rather general origin

Formal methods for dependable real-time systems

Science.gov (United States)

Rushby, John

1993-01-01

The motivation for using formal methods to specify and reason about real time properties is outlined and approaches that were proposed and used are sketched. The formal verifications of clock synchronization algorithms are concluded as showing that mechanically supported reasoning about complex real time behavior is feasible. However, there was significant increase in the effectiveness of verification systems since those verifications were performed, at it is to be expected that verifications of comparable difficulty will become fairly routine. The current challenge lies in developing perspicuous and economical approaches to the formalization and specification of real time properties.

Real-time observation of coadsorption layers on Ru(001) using a temperature-programmed ESDIAD/TOF system

Science.gov (United States)

Sasaki, T.; Itai, Y.; Iwasawa, Y.

1997-11-01

For the purpose of utilizing ESDIAD as a real-time probe for surface processes, we have developed an instrument which can measure ESDIAD images and time of flight (TOF) spectra of desorbing ions in temperature-programmed surface processes. TOF measurements are carried out to identify the mass and to determine the kinetic energy distribution of the desorbed ions. This temperature-programmed (TP-) ESDIAD/TOF system was used to observe coadsorption layers of methylamine and CO on Ru(001) which have been previously studied by our group using LEED, TPD and HREELS, also drawing upon a comparison of findings with the coadsorption system of CO and ammonia. ESDIAD images acquired for temperature-programmed surface processes in real time were found to provide new insight into the dynamic behaviour of the coadsorption layers. As to the pure adsorption of ammonia and methylamine, the second and the first (chemisorbed) layers can be easily discriminated in their different ESD detection efficiency due to the difference in neutralization rate. The intensity change of H + ions with temperature shows the process of the decomposition of methylamine to be dependent on CO coverage. The intensity of O + originating from CO changes due to the change of CO adsorption site in the reaction process. The angular distribution of H + ions which correspond to CH2NH…Ru species appears at 250-300 K in the presence of high CO pre-coverage.

TEM Study of High-Temperature Precipitation of Delta Phase in Inconel 718 Alloy

Directory of Open Access Journals (Sweden)

Moukrane Dehmas

2011-01-01

Full Text Available Inconel 718 is widely used because of its ability to retain strength at up to 650∘C for long periods of time through coherent metastable  Ni3Nb precipitation associated with a smaller volume fraction of  Ni3Al precipitates. At very long ageing times at service temperature,  decomposes to the stable Ni3Nb phase. This latter phase is also present above the  solvus and is used for grain control during forging of alloy 718. While most works available on precipitation have been performed at temperatures below the  solvus, it appeared of interest to also investigate the case where phase precipitates directly from the fcc matrix free of  precipitates. This was studied by X-ray diffraction and transmission electron microscopy (TEM. TEM observations confirmed the presence of rotation-ordered domains in plates, and some unexpected contrast could be explained by double diffraction due to overlapping phases.

Study on Real-Time Simulation Analysis and Inverse Analysis System for Temperature and Stress of Concrete Dam

Directory of Open Access Journals (Sweden)

Lei Zhang

2015-01-01

Full Text Available In the concrete dam construction, it is very necessary to strengthen the real-time monitoring and scientific management of concrete temperature control. This paper constructs the analysis and inverse analysis system of temperature stress simulation, which is based on various useful data collected in real time in the process of concrete construction. The system can produce automatically data file of temperature and stress calculation and then achieve the remote real-time simulation calculation of temperature stress by using high performance computing techniques, so the inverse analysis can be carried out based on a basis of monitoring data in the database; it fulfills the automatic feedback calculation according to the error requirement and generates the corresponding curve and chart after the automatic processing and analysis of corresponding results. The system realizes the automation and intellectualization of complex data analysis and preparation work in simulation process and complex data adjustment in the inverse analysis process, which can facilitate the real-time tracking simulation and feedback analysis of concrete temperature stress in construction process and enable you to discover problems timely, take measures timely, and adjust construction scheme and can well instruct you how to ensure project quality.

Real-time synchrotoron radiation X-ray diffraction and abnormal temperature dependence of photoluminescence from erbium silicates on SiO2/Si substrates

Directory of Open Access Journals (Sweden)

H. Omi

2012-03-01

Full Text Available The erbium silicate formation processes during annealing in Ar gas were monitored by synchrotron radiation grazing incidence X-ray diffraction (GIXD in real time and the optical properties of the silicates were investigated by photoluminescence measurements in spectral and time-resolved domains. The GIXD measurements show that erbium silicates and erbium oxide are formed by interface reactions between silicon oxide and erbium oxides deposited on silicon oxide by reactive sputtering in Ar gas and O2/Ar mixture gas ambiences. The erbium silicates are formed above 1060 °C in Ar gas ambience and above 1010 °C in O2/Ar gas ambience, and erbium silicides are dominantly formed above 1250 °C. The I15/2-I13/2 Er3+ photoluminescence from the erbium oxide and erbium silicate exhibits abnormal temperature dependence, which can be explained by the phonon-assisted resonant absorption of the 532-nm excitation photons into the 2H11/2 levels of Er3+ ions of the erbium compounds.

A Distributed Computing Network for Real-Time Systems.

Science.gov (United States)

1980-11-03

7 ) AU2 o NAVA TUNDEWATER SY$TEMS CENTER NEWPORT RI F/G 9/2 UIS RIBUT E 0 COMPUTIN G N LTWORK FOR REAL - TIME SYSTEMS .(U) UASSIFIED NOV Al 6 1...MORAIS - UT 92 dLEVEL c A Distributed Computing Network for Real - Time Systems . 11 𔃺-1 Gordon E/Morson I7 y tm- ,r - t "en t As J 2 -p .. - 7 I’ cNaval...NUMBER TD 5932 / N 4. TITLE mand SubotI. S. TYPE OF REPORT & PERIOD COVERED A DISTRIBUTED COMPUTING NETWORK FOR REAL - TIME SYSTEMS 6. PERFORMING ORG

Implementation of the frequency dependent line model in a real-time power system simulator

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Reynaldo Iracheta-Cortez

2017-09-01

Full Text Available In this paper is described the implementation of the frequency-dependent line model (FD-Line in a real-time digital power system simulator. The main goal with such development is to describe a general procedure to incorporate new realistic models of power system components in modern real-time simulators based on the Electromagnetic Transients Program (EMTP. In this procedure are described, firstly, the steps to obtain the time domain solution of the differential equations that models the electromagnetic behavior in multi-phase transmission lines with frequency dependent parameters. After, the algorithmic solution of the FD-Line model is implemented in Simulink environment, through an S-function programmed in C language, for running off-line simulations of electromagnetic transients. This implementation allows the free assembling of the FD Line model with any element of the Power System Blockset library and also, it can be used to build any network topology. The main advantage of having a power network built in Simulink is that can be executed in real-time by means of the commercial eMEGAsim simulator. Finally, several simulation cases are presented to validate the accuracy and the real-time performance of the FD-Line model.

Development of a multiplex real-time PCR for the rapid detection of the predominant beta-lactamase genes CTX-M, SHV, TEM and CIT-type AmpCs in Enterobacteriaceae.

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Nicole Roschanski

Full Text Available Beta-lactamase resistant bacteria and especially ESBL producing Enterobacteriaceae are an increasing problem worldwide. For this reason a major interest in efficient and reliable methods for rapid screening of high sample numbers is recognizable. Therefore, a multiplex real-time PCR was developed to detect the predominant class A beta-lactamase genes blaCTX-M, blaSHV, blaTEM and CIT-type AmpCs in a one-step reaction. A set of 114 Enterobacteriaceae containing previously identified resistance gene subtypes and in addition 20 undefined animal and environmental isolates were used for the validation of this assay. To confirm the accessibility in variable settings, the real-time runs were performed analogous in two different laboratories using different real-time cyclers. The obtained results showed complete accordance between the real-time data and the predetermined genotypes. Even if sequence analyses are further necessary for a comprehensive characterization, this method was proofed to be reliable for rapid screening of high sample numbers and therefore could be an important tool for e. g. epidemiological purposes or support infection control measures.

Time dependent temperature distribution in pulsed Ti:sapphire lasers

Science.gov (United States)

Buoncristiani, A. Martin; Byvik, Charles E.; Farrukh, Usamah O.

1988-01-01

An expression is derived for the time dependent temperature distribution in a finite solid state laser rod for an end-pumped beam of arbitrary shape. The specific case of end pumping by circular (constant) or Gaussian beam is described. The temperature profile for a single pump pulse and for repetitive pulse operation is discussed. The particular case of the temperature distribution in a pulsed titanium:sapphire rod is considered.

Real time X-ray scattering study of the formation of ZnS nanoparticles using synchrotron radiation

International Nuclear Information System (INIS)

Rath, T.; Novák, J.; Amenitsch, H.; Pein, A.; Maier, E.; Haas, W.; Hofer, F.; Trimmel, G.

2014-01-01

We investigate the growth of ZnS nanoparticles by a real-time simultaneous small and wide angle X-ray scattering (SAXS, WAXS) study using synchrotron radiation. Zinc chloride and elemental sulfur were dissolved in oleylamine. The formation of nanoparticles was induced by heating to 170 °C and 215 °C. The influence of temperature, reaction time, and sulfur concentration was investigated. After a short phase of rapid growth, saturation in size and a slower growth is observed depending on the temperature. The final size of the nanoparticles ranges between 2 and 6 nm for the investigated growth conditions and increases with the reaction temperature and sulfur concentration. SAXS analysis allows for determination of the size of the nanoparticles and proves also the existence of an organized layer of oleylamine molecules covering the nanoparticles' surfaces, which, however, appears only for diameters of the nanoparticles larger than approximately 2.8 nm. The investigation of the measured structure factor of the nanoparticle assemblies showed that the distance of an attractive interaction is 2.5 nm, which was interpreted as a consequence of the ordered oleylamine surface layer. - Highlights: • ZnS nanoparticle growth is investigated by real-time simultaneous SAXS and WAXS measurements. • Nanoparticle growth can be divided into two growth phases. • Higher reaction temperature or higher surplus of sulfur leads to larger nanoparticles. • Post-growth ex situ XRD and TEM measurements confirm results of the in situ study. • Nanoparticles are surrounded by a 2.6 nm thick ordered shell of oleylamine

Real time thermal hydraulic model for high temperature gas-cooled reactor core

International Nuclear Information System (INIS)

Sui Zhe; Sun Jun; Ma Yuanle; Zhang Ruipeng

2013-01-01

A real-time thermal hydraulic model of the reactor core was described and integrated into the simulation system for the high temperature gas-cooled pebble bed reactor nuclear power plant, which was developed in the vPower platform, a new simulation environment for nuclear and fossil power plants. In the thermal hydraulic model, the helium flow paths were established by the flow network tools in order to obtain the flow rates and pressure distributions. Meanwhile, the heat structures, representing all the solid heat transfer elements in the pebble bed, graphite reflectors and carbon bricks, were connected by the heat transfer network in order to solve the temperature distributions in the reactor core. The flow network and heat transfer network were coupled and calculated in real time. Two steady states (100% and 50% full power) and two transients (inlet temperature step and flow step) were tested that the quantitative comparisons of the steady results with design data and qualitative analysis of the transients showed the good applicability of the present thermal hydraulic model. (authors)

[Real time diagnostics of instantaneous temperature of combustion and explosion process by modern spectroscopy].

Science.gov (United States)

Zhou, Xue-tie; Wang, Jun-de; Li, Yan; Liu, Da-bing

2003-04-01

The combustion temperature is one of the important parameters to express flame combustion and explosion characteristics. It will effectively guide the design and manufacture of new model explosives, industrial explosive materials, and weapons. The recent developments and applications of real time diagnostics of instantaneous temperature of combustion and explosion processes by modern spectroscopic methods, such as atomic absorption-emission method, atomic emission two-line spectroscopy, atomic emission multiline spectroscopy, molecular rotation-vibration spectroscopy, coherent anti-stokes Raman scattering (CARS) and plane laser-induced fluorescence (PLIF), were reviewed in this paper. The maximum time resolution of atomic absorption-emission method is 25 microseconds. The time resolution of atomic emission two-line spectroscopy can reach 0.1 microsecond. These two methods can completely suit the need of real time and instantaneous temperature diagnostics of violent explosion and flame combustion. Other methods will also provide new effective research methods for the processes and characteristics of combustion, flame and explosion.

A real-time heat strain risk classifier using heart rate and skin temperature

International Nuclear Information System (INIS)

Buller, Mark J; Latzka, William A; Yokota, Miyo; Tharion, William J; Moran, Daniel S

2008-01-01

Heat injury is a real concern to workers engaged in physically demanding tasks in high heat strain environments. Several real-time physiological monitoring systems exist that can provide indices of heat strain, e.g. physiological strain index (PSI), and provide alerts to medical personnel. However, these systems depend on core temperature measurement using expensive, ingestible thermometer pills. Seeking a better solution, we suggest the use of a model which can identify the probability that individuals are 'at risk' from heat injury using non-invasive measures. The intent is for the system to identify individuals who need monitoring more closely or who should apply heat strain mitigation strategies. We generated a model that can identify 'at risk' (PSI ≥ 7.5) workers from measures of heart rate and chest skin temperature. The model was built using data from six previously published exercise studies in which some subjects wore chemical protective equipment. The model has an overall classification error rate of 10% with one false negative error (2.7%), and outperforms an earlier model and a least squares regression model with classification errors of 21% and 14%, respectively. Additionally, the model allows the classification criteria to be adjusted based on the task and acceptable level of risk. We conclude that the model could be a valuable part of a multi-faceted heat strain management system. (note)

Excited-state absorption in tetrapyridyl porphyrins: comparing real-time and quadratic-response time-dependent density functional theory

Energy Technology Data Exchange (ETDEWEB)

Bowman, David N. [Department of Chemistry; Supercomputing Institute and Chemical Theory Center; University of Minnesota; Minneapolis; USA; Asher, Jason C. [Department of Chemistry; Supercomputing Institute and Chemical Theory Center; University of Minnesota; Minneapolis; USA; Fischer, Sean A. [William R. Wiley Environmental Molecular Sciences Laboratory; Pacific Northwest National Laboratory; P.O. Box 999; Richland; USA; Cramer, Christopher J. [Department of Chemistry; Supercomputing Institute and Chemical Theory Center; University of Minnesota; Minneapolis; USA; Govind, Niranjan [William R. Wiley Environmental Molecular Sciences Laboratory; Pacific Northwest National Laboratory; P.O. Box 999; Richland; USA

2017-01-01

Threemeso-substituted tetrapyridyl porphyrins (free base, Ni(ii), and Cu(ii)) were investigated for their optical limiting (OL) capabilities using real-time (RT-), linear-response (LR-), and quadratic-response (QR-) time-dependent density functional theory (TDDFT) methods.

Real-time correction of tsunami site effect by frequency-dependent tsunami-amplification factor

Science.gov (United States)

Tsushima, H.

2017-12-01

For tsunami early warning, I developed frequency-dependent tsunami-amplification factor and used it to design a recursive digital filter that can be applicable for real-time correction of tsunami site response. In this study, I assumed that a tsunami waveform at an observing point could be modeled by convolution of source, path and site effects in time domain. Under this assumption, spectral ratio between offshore and the nearby coast can be regarded as site response (i.e. frequency-dependent amplification factor). If the amplification factor can be prepared before tsunamigenic earthquakes, its temporal convolution to offshore tsunami waveform provides tsunami prediction at coast in real time. In this study, tsunami waveforms calculated by tsunami numerical simulations were used to develop frequency-dependent tsunami-amplification factor. Firstly, I performed numerical tsunami simulations based on nonlinear shallow-water theory from many tsuanmigenic earthquake scenarios by varying the seismic magnitudes and locations. The resultant tsunami waveforms at offshore and the nearby coastal observing points were then used in spectral-ratio analysis. An average of the resulted spectral ratios from the tsunamigenic-earthquake scenarios is regarded as frequency-dependent amplification factor. Finally, the estimated amplification factor is used in design of a recursive digital filter that can be applicable in time domain. The above procedure is applied to Miyako bay at the Pacific coast of northeastern Japan. The averaged tsunami-height spectral ratio (i.e. amplification factor) between the location at the center of the bay and the outside show a peak at wave-period of 20 min. A recursive digital filter based on the estimated amplification factor shows good performance in real-time correction of tsunami-height amplification due to the site effect. This study is supported by Japan Society for the Promotion of Science (JSPS) KAKENHI grant 15K16309.

In Situ TEM Electrical Measurements

DEFF Research Database (Denmark)

Canepa, Silvia; Alam, Sardar Bilal; Ngo, Duc-The

2016-01-01

understanding of complex physical and chemical interactions in the pursuit to optimize nanostructure function and device performance. Recent developments of sample holder technology for TEM have enabled a new field of research in the study of functional nanomaterials and devices via electrical stimulation...... influence the sample by external stimuli, e.g. through electrical connections, the TEM becomes a powerful laboratory for performing quantitative real time in situ experiments. Such TEM setups enable the characterization of nanostructures and nanodevices under working conditions, thereby providing a deeper...... and measurement of the specimen. Recognizing the benefits of electrical measurements for in situ TEM, many research groups have focused their effort in this field and some of these methods have transferred to ETEM. This chapter will describe recent advances in the in situ TEM investigation of nanostructured...

Temperature-Controlled High-Speed AFM: Real-Time Observation of Ripple Phase Transitions.

Science.gov (United States)

Takahashi, Hirohide; Miyagi, Atsushi; Redondo-Morata, Lorena; Scheuring, Simon

2016-11-01

With nanometer lateral and Angstrom vertical resolution, atomic force microscopy (AFM) has contributed unique data improving the understanding of lipid bilayers. Lipid bilayers are found in several different temperature-dependent states, termed phases; the main phases are solid and fluid phases. The transition temperature between solid and fluid phases is lipid composition specific. Under certain conditions some lipid bilayers adopt a so-called ripple phase, a structure where solid and fluid phase domains alternate with constant periodicity. Because of its narrow regime of existence and heterogeneity ripple phase and its transition dynamics remain poorly understood. Here, a temperature control device to high-speed atomic force microscopy (HS-AFM) to observe dynamics of phase transition from ripple phase to fluid phase reversibly in real time is developed and integrated. Based on HS-AFM imaging, the phase transition processes from ripple phase to fluid phase and from ripple phase to metastable ripple phase to fluid phase could be reversibly, phenomenologically, and quantitatively studied. The results here show phase transition hysteresis in fast cooling and heating processes, while both melting and condensation occur at 24.15 °C in quasi-steady state situation. A second metastable ripple phase with larger periodicity is formed at the ripple phase to fluid phase transition when the buffer contains Ca 2+ . The presented temperature-controlled HS-AFM is a new unique experimental system to observe dynamics of temperature-sensitive processes at the nanoscopic level. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nanomechanical and in situ TEM characterization of boron carbide thin films on helium implanted substrates: Delamination, real-time cracking and substrate buckling

Energy Technology Data Exchange (ETDEWEB)

Framil Carpeño, David, E-mail: david.framil-carpeno@auckland.ac.nz [Department of Chemical and Materials Engineering, The University of Auckland, 20 Symonds Street, Auckland 1010 (New Zealand); Ohmura, Takahito; Zhang, Ling [Strength Design Group, Structural Materials Unit, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Leveneur, Jérôme [National Isotope Centre, GNS Science, 30 Gracefield Road, Gracefield, Lower Hutt 5010 (New Zealand); Dickinson, Michelle [Department of Chemical and Materials Engineering, The University of Auckland, 20 Symonds Street, Auckland 1010 (New Zealand); Seal, Christopher [International Centre for Advanced Materials, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Kennedy, John [National Isotope Centre, GNS Science, 30 Gracefield Road, Gracefield, Lower Hutt 5010 (New Zealand); Hyland, Margaret [Department of Chemical and Materials Engineering, The University of Auckland, 20 Symonds Street, Auckland 1010 (New Zealand)

2015-07-15

Boron carbide coatings deposited on helium-implanted and unimplanted Inconel 600 were characterized using a combination of nanoindentation and transmission electron microscopy. Real-time coating, cracking and formation of slip bands were recorded using in situ TEM-nanoindentation, allowing site specific events to be correlated with specific features in their load–displacement curves. Cross-sections through the residual indent impression showed a correlation between pop-outs in the load–displacement curves and coating delamination, which was confirmed with cyclic indentation experiments. Inconel exhibits (-11-1) and (1-1-1) twin variants in its deformed region beneath the indenter, organized in bands with a ladder-like arrangement. The nanomechanical properties of the metal–ceramic coating combinations exhibit a marked substrate effect as a consequence of helium implantation.

Nanomechanical and in situ TEM characterization of boron carbide thin films on helium implanted substrates: Delamination, real-time cracking and substrate buckling

International Nuclear Information System (INIS)

Framil Carpeño, David; Ohmura, Takahito; Zhang, Ling; Leveneur, Jérôme; Dickinson, Michelle; Seal, Christopher; Kennedy, John; Hyland, Margaret

2015-01-01

Boron carbide coatings deposited on helium-implanted and unimplanted Inconel 600 were characterized using a combination of nanoindentation and transmission electron microscopy. Real-time coating, cracking and formation of slip bands were recorded using in situ TEM-nanoindentation, allowing site specific events to be correlated with specific features in their load–displacement curves. Cross-sections through the residual indent impression showed a correlation between pop-outs in the load–displacement curves and coating delamination, which was confirmed with cyclic indentation experiments. Inconel exhibits (-11-1) and (1-1-1) twin variants in its deformed region beneath the indenter, organized in bands with a ladder-like arrangement. The nanomechanical properties of the metal–ceramic coating combinations exhibit a marked substrate effect as a consequence of helium implantation

Real-time three-dimensional temperature mapping in photothermal therapy with optoacoustic tomography

Science.gov (United States)

Oyaga Landa, Francisco Javier; Deán-Ben, Xosé Luís.; Sroka, Ronald; Razansky, Daniel

2017-07-01

Ablation and photothermal therapy are widely employed medical protocols where the selective destruction of tissue is a necessity as in cancerous tissue removal or vascular and brain abnormalities. Tissue denaturation takes place when the temperature reaches a threshold value while the time of exposure determines the lesion size. Therefore, the spatio-temporal distribution of temperature plays a crucial role in the outcome of these clinical interventions. We demonstrate fast volumetric temperature mapping with optoacoustic tomography based on real-time optoacoustic readings from the treated region. The performance of the method was investigated in tissue-mimicking phantom experiments. The new ability to non-invasively measure temperature volumetrically in an entire treated region with high spatial and temporal resolutions holds potential for improving safety and efficacy of thermal ablation and to advance the general applicability of laser-based therapy.

A Real-Time Temperature Data Transmission Approach for Intelligent Cooling Control of Mass Concrete

Directory of Open Access Journals (Sweden)

Peng Lin

2014-01-01

Full Text Available The primary aim of the study presented in this paper is to propose a real-time temperature data transmission approach for intelligent cooling control of mass concrete. A mathematical description of a digital temperature control model is introduced in detail. Based on pipe mounted and electrically linked temperature sensors, together with postdata handling hardware and software, a stable, real-time, highly effective temperature data transmission solution technique is developed and utilized within the intelligent mass concrete cooling control system. Once the user has issued the relevant command, the proposed programmable logic controllers (PLC code performs all necessary steps without further interaction. The code can control the hardware, obtain, read, and perform calculations, and display the data accurately. Hardening concrete is an aggregate of complex physicochemical processes including the liberation of heat. The proposed control system prevented unwanted structural change within the massive concrete blocks caused by these exothermic processes based on an application case study analysis. In conclusion, the proposed temperature data transmission approach has proved very useful for the temperature monitoring of a high arch dam and is able to control thermal stresses in mass concrete for similar projects involving mass concrete.

Temperature dependence of fluorescence decay time and emission spectrum of bismuth germanate

International Nuclear Information System (INIS)

Melcher, C.L.; Liberman, A.; Schweitzer, J.S.; Simonetti, J.

1985-01-01

Bismuth germanate has become an increasingly popular replacement for NaI(Tl) scintillators in recent years, mainly due to its higher detection efficiency. However, its scintillation efficiency and fluorescence decay time are strongly temperature dependent. Optimum performance of detector systems which employ BGO crystals depends on knowledge of the BGO pulse shape and intensity and its emission spectrum at the operating temperature of the detector. Measurements of these quantities are presented over the temperature range -47 0 C to +111 0 C. Although the emission spectrum shifts only slightly over this temperature range, the scintillation efficiency and fluorescence decay time are strongly temperature dependent. In addition to the usefulness of these data for optimizing detector design, the results imply that luminescence quenching in BGO cannot be characterized by a single thermal activation to a radiationless transition but that a more complex model is required to characterize the light output from BGO crystals

3D Printed "Earable" Smart Devices for Real-Time Detection of Core Body Temperature.

Science.gov (United States)

Ota, Hiroki; Chao, Minghan; Gao, Yuji; Wu, Eric; Tai, Li-Chia; Chen, Kevin; Matsuoka, Yasutomo; Iwai, Kosuke; Fahad, Hossain M; Gao, Wei; Nyein, Hnin Yin Yin; Lin, Liwei; Javey, Ali

2017-07-28

Real-time detection of basic physiological parameters such as blood pressure and heart rate is an important target in wearable smart devices for healthcare. Among these, the core body temperature is one of the most important basic medical indicators of fever, insomnia, fatigue, metabolic functionality, and depression. However, traditional wearable temperature sensors are based upon the measurement of skin temperature, which can vary dramatically from the true core body temperature. Here, we demonstrate a three-dimensional (3D) printed wearable "earable" smart device that is designed to be worn on the ear to track core body temperature from the tympanic membrane (i.e., ear drum) based on an infrared sensor. The device is fully integrated with data processing circuits and a wireless module for standalone functionality. Using this smart earable device, we demonstrate that the core body temperature can be accurately monitored regardless of the environment and activity of the user. In addition, a microphone and actuator are also integrated so that the device can also function as a bone conduction hearing aid. Using 3D printing as the fabrication method enables the device to be customized for the wearer for more personalized healthcare. This smart device provides an important advance in realizing personalized health care by enabling real-time monitoring of one of the most important medical parameters, core body temperature, employed in preliminary medical screening tests.

X-ray absorption in insulators with non-Hermitian real-time time-dependent density functional theory.

Science.gov (United States)

Fernando, Ranelka G; Balhoff, Mary C; Lopata, Kenneth

2015-02-10

Non-Hermitian real-time time-dependent density functional theory was used to compute the Si L-edge X-ray absorption spectrum of α-quartz using an embedded finite cluster model and atom-centered basis sets. Using tuned range-separated functionals and molecular orbital-based imaginary absorbing potentials, the excited states spanning the pre-edge to ∼20 eV above the ionization edge were obtained in good agreement with experimental data. This approach is generalizable to TDDFT studies of core-level spectroscopy and dynamics in a wide range of materials.

Temperature dependence of relaxation times in proton components of fatty acids

International Nuclear Information System (INIS)

Kuroda, Kagayaki; Iwabuchi, Taku; Saito, Kensuke; Obara, Makoto; Honda, Masatoshi; Imai, Yutaka

2011-01-01

We examined the temperature dependence of relaxation times in proton components of fatty acids in various samples in vitro at 11 tesla as a standard calibration data for quantitative temperature imaging of fat. The spin-lattice relaxation time, T 1 , of both the methylene (CH 2 ) chain and terminal methyl (CH 3 ) was linearly related to temperature (r>0.98, P 2 signal for calibration and observed the signal with 18% of CH 3 to estimate temperature. These findings suggested that separating the fatty acid components would significantly improve accuracy in quantitative thermometry for fat. Use of the T 1 of CH 2 seems promising in terms of reliability and reproducibility in measuring temperature of fat. (author)

Correlating TEM images of damage in irradiated materials to molecular dynamics simulations

International Nuclear Information System (INIS)

Schaeublin, R.; Caturla, M.-J.; Wall, M.; Felter, T.; Fluss, M.; Wirth, B.D.; Diaz de la Rubia, T.; Victoria, M.

2002-01-01

TEM image simulations are used to couple the results from molecular dynamics (MD) simulations to experimental TEM images. In particular we apply this methodology to the study of defects produced during irradiation. MD simulations have shown that irradiation of FCC metals results in a population of vacancies and interstitials forming clusters. The limitation of these simulations is the short time scales available, on the order of 100 s of picoseconds. Extrapolation of the results from these short times to the time scales of the laboratory has been difficult. We address this problem by two methods: we perform TEM image simulations of MD simulations of cascades with an improved technique, to relate defects produced at short time scales with those observed experimentally at much longer time scales. On the other hand we perform in situ TEM experiments of Au irradiated at liquid-nitrogen temperatures, and study the evolution of the produced damage as the temperature is increased to room temperature. We find that some of the defects observed in the MD simulations at short time scales using the TEM image simulation technique have features that resemble those observed in laboratory TEM images of irradiated samples. In situ TEM shows that stacking fault tetrahedra are present at the lowest temperatures and are stable during annealing up to room temperature, while other defect clusters migrate one dimensionally above -100 deg. C. Results are presented here

Apple detection using infrared thermal image, 3: Real-time temperature measurement of apple tree

International Nuclear Information System (INIS)

Zhang, S.H.; Takahashi, T.; Fukuchi, H.; Sun, M.; Terao, H.

1998-01-01

In Part 1, we reported the thermal distribution characteristics and the identification methods of apples, leaves and branches by using the infrared thermal image at the specific time. This paper reports the temperature changing characteristics and the relationships among apples, leaves and air temperature based on the information measured by the infrared thermal image equipment in the real-time for 24 hours. As a result, it was confirmed that the average temperature of apples was 1 degree C or more higher than the one of the leaves, and the average temperature of the leaves was almost same as the air temperature within daytime and about 3 hours period after sunset. It was also clarified for a remarkable temperature difference not to exist for midnight and the early morning between the apples and the leaves, and both became almost as well as the air temperature. Moreover, a binary image was easily obtained and the apples could be detected by using this temperature difference informat

Predicting long-term temperature increase for time-dependent SAR levels with a single short-term temperature response.

Science.gov (United States)

Carluccio, Giuseppe; Bruno, Mary; Collins, Christopher M

2016-05-01

Present a novel method for rapid prediction of temperature in vivo for a series of pulse sequences with differing levels and distributions of specific energy absorption rate (SAR). After the temperature response to a brief period of heating is characterized, a rapid estimate of temperature during a series of periods at different heating levels is made using a linear heat equation and impulse-response (IR) concepts. Here the initial characterization and long-term prediction for a complete spine exam are made with the Pennes' bioheat equation where, at first, core body temperature is allowed to increase and local perfusion is not. Then corrections through time allowing variation in local perfusion are introduced. The fast IR-based method predicted maximum temperature increase within 1% of that with a full finite difference simulation, but required less than 3.5% of the computation time. Even higher accelerations are possible depending on the time step size chosen, with loss in temporal resolution. Correction for temperature-dependent perfusion requires negligible additional time and can be adjusted to be more or less conservative than the corresponding finite difference simulation. With appropriate methods, it is possible to rapidly predict temperature increase throughout the body for actual MR examinations. © 2015 Wiley Periodicals, Inc.

A Realization of Temperature Monitoring System Based on Real-Time Kernel μC/OS and 1-wire Bus

Directory of Open Access Journals (Sweden)

Yanmei Qi

2013-06-01

Full Text Available The traditional temperature monitoring system generally adopt some analog sensors for collecting data and a microcontroller for processing data for the purpose of temperature monitoring. However, this back-fore ground system has the disadvantages that the system has poor real-time property and single function, the amount of sensors is not easy to expand, and the software system has a difficulty in upgrading. Aiming at these disadvantages, the system designed in this paper adopts brand-new hardware and software structures: a digitaltemperature sensor array is connected to 1-wire bus and communicated with a control core through 1-wire bus protocol, thus a great convenience is provided for the expansion of the sensor; a real-time operating system is introduced into the software, an application program capable of realizing various functions runs on the real-time kernel μC/OS-II platform. The application of the real-time kernel also provides a good lower layer interface for the late-stage software upgrading.

Temperature and driving field dependence of fatigue processes in PZT bulk ceramics

International Nuclear Information System (INIS)

Glaum, Julia; Granzow, Torsten; Schmitt, Ljubomira Ana; Kleebe, Hans-Joachim; Roedel, Juergen

2011-01-01

The temperature- and field-dependent degradation properties of bulk Pb(Zr,Ti)O 3 material (PZT) under a unipolar electric field were investigated. Unipolar cycling leads to the build-up of an internal bias field based on the agglomeration of charges at grain boundaries. A simple model was developed which describes the general dynamics of unipolar fatigue and its dependence on temperature and driving field. Comparing the large and small signal permittivity before and after fatigue led to the conclusion that domain walls became clamped by the agglomerated charges. This clamping effect could be visualized by transmission electron microscopy (TEM). Additionally, the TEM investigations revealed that unipolar fatigue leads to a weakening of the microstructure and to the development of microcracks.

Real time nanoscale structural evaluation of gold structures on Si (100) surface using in-situ transmission electron microscopy

International Nuclear Information System (INIS)

Rath, A.; Juluri, R. R.; Satyam, P. V.

2014-01-01

Transport behavior of gold nanostructures on Si(100) substrate during annealing under high vacuum has been investigated using in-situ real time transmission electron microscopy (TEM). A comparative study has been done on the morphological changes due to annealing under different vacuum environments. Au thin films of thickness ∼2.0 nm were deposited on native oxide covered silicon substrate by using thermal evaporation system. In-situ real time TEM measurements at 850 °C showed the isotropic growth of rectangular/square shaped gold-silicon alloy structures. During the growth, it is observed that the alloying occurs in liquid phase followed by transformation into the rectangular shapes. For similar system, ex-situ annealing in low vacuum (10 −2 millibars) at 850 °C showed the spherical gold nanostructures with no Au-Si alloy formation. Under low vacuum annealing conditions, the rate of formation of the oxide layer dominates the oxide desorption rate, resulting in the creation of a barrier layer between Au and Si, which restricts the inter diffusion of Au in to Si. This work demonstrates the important role of interfacial oxide layer on the growth of nanoscale Au-Si alloy structures during the initial growth. The time dependent TEM images are presented to offer a direct insight into the fundamental dynamics of the sintering process at the nanoscale

Two-electron Rabi oscillations in real-time time-dependent density-functional theory

International Nuclear Information System (INIS)

Habenicht, Bradley F.; Tani, Noriyuki P.; Provorse, Makenzie R.; Isborn, Christine M.

2014-01-01

We investigate the Rabi oscillations of electrons excited by an applied electric field in several simple molecular systems using time-dependent configuration interaction (TDCI) and real-time time-dependent density-functional theory (RT-TDDFT) dynamics. While the TDCI simulations exhibit the expected single-electron Rabi oscillations at a single resonant electric field frequency, Rabi oscillations in the RT-TDDFT simulations are a two-electron process. The existence of two-electron Rabi oscillations is determined both by full population inversion between field-free molecular orbitals and the behavior of the instantaneous dipole moment during the simulations. Furthermore, the Rabi oscillations in RT-TDDFT are subject to an intensity threshold of the electric field, below which Rabi oscillations do not occur and above which the two-electron Rabi oscillations occur at a broad range of frequencies. It is also shown that at field intensities near the threshold intensity, the field frequency predicted to induce Rabi oscillations by linear response TDDFT only produces detuned Rabi oscillations. Instead, the field frequency that yields the full two-electron population inversion and Rabi oscillation behavior is shown to be the average of single-electron transition frequencies from the ground S 0 state and the doubly-excited S 2 state. The behavior of the two-electron Rabi oscillations is rationalized via two possible models. The first model is a multi-photon process that results from the electric field interacting with the three level system such that three level Rabi oscillations may occur. The second model suggests that the mean-field nature of RT-TDDFT induces paired electron propagation

Large-strain optical fiber sensing and real-time FEM updating of steel structures under the high temperature effect

International Nuclear Information System (INIS)

Huang, Ying; Fang, Xia; Xiao, Hai; Bevans, Wesley James; Chen, Genda; Zhou, Zhi

2013-01-01

Steel buildings are subjected to fire hazards during or immediately after a major earthquake. Under combined gravity and thermal loads, they have non-uniformly distributed stiffness and strength, and thus collapse progressively with large deformation. In this study, large-strain optical fiber sensors for high temperature applications and a temperature-dependent finite element model updating method are proposed for accurate prediction of structural behavior in real time. The optical fiber sensors can measure strains up to 10% at approximately 700 °C. Their measurements are in good agreement with those from strain gauges up to 0.5%. In comparison with the experimental results, the proposed model updating method can reduce the predicted strain errors from over 75% to below 20% at 800 °C. The minimum number of sensors in a fire zone that can properly characterize the vertical temperature distribution of heated air due to the gravity effect should be included in the proposed model updating scheme to achieve a predetermined simulation accuracy. (paper)

Time- and task-dependent non-neural effects of real and sham TMS.

Directory of Open Access Journals (Sweden)

Felix Duecker

Full Text Available Transcranial magnetic stimulation (TMS is widely used in experimental brain research to manipulate brain activity in humans. Next to the intended neural effects, every TMS pulse produces a distinct clicking sound and sensation on the head which can also influence task performance. This necessitates careful consideration of control conditions in order to ensure that behavioral effects of interest can be attributed to the neural consequences of TMS and not to non-neural effects of a TMS pulse. Surprisingly, even though these non-neural effects of TMS are largely unknown, they are often assumed to be unspecific, i.e. not dependent on TMS parameters. This assumption is inherent to many control strategies in TMS research but has recently been challenged on empirical grounds. Here, we further develop the empirical basis of control strategies in TMS research. We investigated the time-dependence and task-dependence of the non-neural effects of TMS and compared real and sham TMS over vertex. Critically, we show that non-neural TMS effects depend on a complex interplay of these factors. Although TMS had no direct neural effects, both pre- and post-stimulus TMS time windows modulated task performance on both a sensory detection task and a cognitive angle judgment task. For the most part, these effects were quantitatively similar across tasks but effect sizes were clearly different. Moreover, the effects of real and sham TMS were almost identical with interesting exceptions that shed light on the relative contribution of auditory and somato-sensory aspects of a TMS pulse. Knowledge of such effects is of critical importance for the interpretation of TMS experiments and helps deciding what constitutes an appropriate control condition. Our results broaden the empirical basis of control strategies in TMS research and point at potential pitfalls that should be avoided.

BINARY: an optical freezing array for assessing temperature and time dependence of heterogeneous ice nucleation

Directory of Open Access Journals (Sweden)

C. Budke

2015-02-01

Full Text Available A new optical freezing array for the study of heterogeneous ice nucleation in microliter-sized droplets is introduced, tested and applied to the study of immersion freezing in aqueous Snomax® suspensions. In the Bielefeld Ice Nucleation ARraY (BINARY ice nucleation can be studied simultaneously in 36 droplets at temperatures down to −40 °C (233 K and at cooling rates between 0.1 and 10 K min−1. The droplets are separated from each other in individual compartments, thus preventing a Wegener–Bergeron–Findeisen type water vapor transfer between droplets as well as avoiding the seeding of neighboring droplets by formation and surface growth of frost halos. Analysis of freezing and melting occurs via an automated real-time image analysis of the optical brightness of each individual droplet. As an application ice nucleation in water droplets containing Snomax® at concentrations from 1 ng mL−1 to 1 mg mL−1 was investigated. Using different cooling rates, a small time dependence of ice nucleation induced by two different classes of ice nucleators (INs contained in Snomax® was detected and the corresponding heterogeneous ice nucleation rate coefficient was quantified. The observed time dependence is smaller than those of other types of INs reported in the literature, suggesting that the BINARY setup is suitable for quantifying time dependence for most other INs of atmospheric interest, making it a useful tool for future investigations.

BINARY: an optical freezing array for assessing temperature and time dependence of heterogeneous ice nucleation

Science.gov (United States)

Budke, C.; Koop, T.

2015-02-01

A new optical freezing array for the study of heterogeneous ice nucleation in microliter-sized droplets is introduced, tested and applied to the study of immersion freezing in aqueous Snomax® suspensions. In the Bielefeld Ice Nucleation ARraY (BINARY) ice nucleation can be studied simultaneously in 36 droplets at temperatures down to -40 °C (233 K) and at cooling rates between 0.1 and 10 K min-1. The droplets are separated from each other in individual compartments, thus preventing a Wegener-Bergeron-Findeisen type water vapor transfer between droplets as well as avoiding the seeding of neighboring droplets by formation and surface growth of frost halos. Analysis of freezing and melting occurs via an automated real-time image analysis of the optical brightness of each individual droplet. As an application ice nucleation in water droplets containing Snomax® at concentrations from 1 ng mL-1 to 1 mg mL-1 was investigated. Using different cooling rates, a small time dependence of ice nucleation induced by two different classes of ice nucleators (INs) contained in Snomax® was detected and the corresponding heterogeneous ice nucleation rate coefficient was quantified. The observed time dependence is smaller than those of other types of INs reported in the literature, suggesting that the BINARY setup is suitable for quantifying time dependence for most other INs of atmospheric interest, making it a useful tool for future investigations.

Self-consistent DFT +U method for real-space time-dependent density functional theory calculations

Science.gov (United States)

Tancogne-Dejean, Nicolas; Oliveira, Micael J. T.; Rubio, Angel

2017-12-01

We implemented various DFT+U schemes, including the Agapito, Curtarolo, and Buongiorno Nardelli functional (ACBN0) self-consistent density-functional version of the DFT +U method [Phys. Rev. X 5, 011006 (2015), 10.1103/PhysRevX.5.011006] within the massively parallel real-space time-dependent density functional theory (TDDFT) code octopus. We further extended the method to the case of the calculation of response functions with real-time TDDFT+U and to the description of noncollinear spin systems. The implementation is tested by investigating the ground-state and optical properties of various transition-metal oxides, bulk topological insulators, and molecules. Our results are found to be in good agreement with previously published results for both the electronic band structure and structural properties. The self-consistent calculated values of U and J are also in good agreement with the values commonly used in the literature. We found that the time-dependent extension of the self-consistent DFT+U method yields improved optical properties when compared to the empirical TDDFT+U scheme. This work thus opens a different theoretical framework to address the nonequilibrium properties of correlated systems.

Effect of milling time and annealing temperature on nanoparticles evolution for 13.5% Cr ODS ferritic steel powders by joint application of XAFS and TEM

Science.gov (United States)

He, P.; Hoffmann, J.; Möslang, A.

2018-04-01

The characteristics of strengthening nanoparticles have a major influence on the mechanical property and irradiation resistance of oxide dispersion strengthened (ODS) steels. To determine how to control nanoparticles evolution, 0.3% Ti with 0.3% Y2O3 were added in 13.5%Cr pre-alloyed steel powders via different milling and consolidation conditions, then characterized by transmission electron microscopy (TEM) and X-ray absorption fine structure (XAFS) at synchrotron irradiation facility. The dissolution of Y2O3 is greatly dependent on the milling time at fixed milling speeds. After 24 h of milling, only minor amounts of the initially added Y2O3 dissolve into the steel matrix whereas TEM results reveal nearly complete dissolution of Y2O3 in 80-h-milled powder. The annealed powder FT-A800 (at 800 °C for 1 h) exhibits a structure near to the initially added Y2O3. The slightly deviation may be accounted for considerable lattice distortion related to the presence of atomic vacancies or formation of Y-Ti-O nucleus. The annealed powders FT-A1000 and FT-A1100 contain complex mixtures of Y-O/Y-Ti-O oxides, which cannot be fitted by any single thermally stable compounds. The coordination numbers of these first two shells in the annealed powders significantly raise as a function of the annealing temperature, indicating the formation of more ordered Y-O or Y-Ti-O particles. The extended X-ray absorption fine structure (EXAFS) spectrum could not necessarily distinguish the dominant oxide species.

Real-time photonic sampling with improved signal-to-noise and distortion ratio using polarization-dependent modulators

Science.gov (United States)

Liang, Dong; Zhang, Zhiyao; Liu, Yong; Li, Xiaojun; Jiang, Wei; Tan, Qinggui

2018-04-01

A real-time photonic sampling structure with effective nonlinearity suppression and excellent signal-to-noise ratio (SNR) performance is proposed. The key points of this scheme are the polarization-dependent modulators (P-DMZMs) and the sagnac loop structure. Thanks to the polarization sensitive characteristic of P-DMZMs, the differences between transfer functions of the fundamental signal and the distortion become visible. Meanwhile, the selection of specific biases in P-DMZMs is helpful to achieve a preferable linearized performance with a low noise level for real-time photonic sampling. Compared with the quadrature-biased scheme, the proposed scheme is capable of valid nonlinearity suppression and is able to provide a better SNR performance even in a large frequency range. The proposed scheme is proved to be effective and easily implemented for real time photonic applications.

Real-time temperature monitoring during radiofrequency treatments on ex-vivo animal model by fiber Bragg grating sensors

Science.gov (United States)

Palumbo, Giovanna; Tosi, Daniele; Schena, Emiliano; Massaroni, Carlo; Ippolito, Juliet; Verze, Paolo; Carlomagno, Nicola; Tammaro, Vincenzo; Iadicicco, Agostino; Campopiano, Stefania

2017-05-01

Fiber Bragg Grating (FBG) sensors applied to bio-medical procedures such as surgery and rehabilitation are a valid alternative to traditional sensing techniques due to their unique characteristics. Herein we propose the use of FBG sensor arrays for accurate real-time temperature measurements during multi-step RadioFrequency Ablation (RFA) based thermal tumor treatment. Real-time temperature monitoring in the RF-applied region represents a valid feedback for the success of the thermo-ablation procedure. In order to create a thermal multi-point map around the tumor area to be treated, a proper sensing configuration was developed. In particular, the RF probe of a commercial medical instrumentation, has been equipped with properly packaged FBGs sensors. Moreover, in order to discriminate the treatment areas to be ablated as precisely as possible, a second array 3.5 cm long, made by several FBGs was used. The results of the temperature measurements during the RFA experiments conducted on ex-vivo animal liver and kidney tissues are presented herein. The proposed FBGs based solution has proven to be capable of distinguish different and consecutive discharges and for each of them, to measure the temperature profile with a resolution of 0.1 °C and a minimum spatial resolution of 5mm. Based upon our experiments, it is possible to confirm that the temperature decreases with distance from a RF peak ablation, in accordance with RF theory. The proposed solution promises to be very useful for the surgeon because a real-time temperature feedback allows for the adaptation of RFA parameters during surgery and better delineates the area under treatment.

Annealing time dependent up-conversion luminescence enhancement in magnesium–tellurite glass

Energy Technology Data Exchange (ETDEWEB)

Amjad, Raja J., E-mail: rajajunaid25@gmail.com [Advanced Optical Material Research Group, Faculty of Science, Universiti Teknologi Malaysia, Skudai, Johor bahru 81310 (Malaysia); Centre for Solid State Physics, University of the Punjab, QAC, Lahore 54590 (Pakistan); Sahar, M.R.; Ghoshal, S.K.; Dousti, M.R. [Advanced Optical Material Research Group, Faculty of Science, Universiti Teknologi Malaysia, Skudai, Johor bahru 81310 (Malaysia); Riaz, S. [Centre for Solid State Physics, University of the Punjab, QAC, Lahore 54590 (Pakistan); Samavati, A.R.; Arifin, R. [Advanced Optical Material Research Group, Faculty of Science, Universiti Teknologi Malaysia, Skudai, Johor bahru 81310 (Malaysia); Naseem, S. [Centre for Solid State Physics, University of the Punjab, QAC, Lahore 54590 (Pakistan)

2013-04-15

Silver nanoparticles (NPs) embedded Er{sup 3+} ions doped magnesium–tellurite glasses are prepared using melt quenching technique. Heat treatment with different time intervals above the glass transition temperature is applied in order to reduce the silver ions (Ag{sup +}) to silver NPs (Ag{sup o}). The transmission electron microscopy (TEM), differential thermal analyses (DTA), UV–vis-NIR absorption spectroscopy and photoluminescence (PL) spectroscopy are used to examine annealing time dependent structural and optical properties. The characteristics temperatures such as glass transition temperature (T{sub g}), crystallization temperature (T{sub c}) and melting temperature (T{sub m}) obtained from DTA for an as prepared sample are 322 °C, 450 °C and 580 °C, respectively. TEM image clearly shows the homogeneous distribution of silver NPs with an average diameter ∼12 nm. The observed localized surface plasmon resonance (LSPR) band is evidenced at 534 nm. Furthermore, the infrared to visible frequency up-conversion (UC) emission under 786 nm excitation exhibits three emission bands centered at 532 nm, 554 nm and 634 nm corresponding to {sup 2}H{sub 11/2}→{sup 4}I{sub 15/2}, {sup 4}S{sub 3/2}→{sup 4}I{sub 15/2} and {sup 4}F{sub 9/2}→{sup 4}I{sub 15/2} transitions of Er{sup 3+}, respectively. Intensity of all the bands is found to enhance by increasing the annealing time up to 24 h. However, further increase in the annealing time duration (∼40 h) reduces the intensity. Enhancement in the luminescence intensity is understood in terms of the local field effect of the silver NPs whereas the quenching is attributed to the energy transfer from Er{sup 3+} ions to silver NPs. -- Highlights: ► Er{sup 3+}-doped silver NPs embedded magnesium–tellurite glasses are prepared. ► TEM confirms the successful precipitation of spherical NPs by heat treatment (HT). ► Luminescence is enhanced due to the growth of NPs after HT up to 24 h. ► With HT>24 h (40 h

Time and temperature dependence of cascade induced defect production in in situ experiments and computer simulation

International Nuclear Information System (INIS)

Ishino, Shiori

1993-01-01

Understanding of the defect production and annihilation processes in a cascade is important in modelling of radiation damage for establishing irradiation correlation. In situ observation of heavy ion radiation damage has a great prospect in this respect. Time and temperature dependence of formation and annihilation of vacancy clusters in a cascade with a time resolution of 30 ms has been studied with a facility which comprises a heavy ion accelerator and an electron microscope. Formation and annihilation rates of defect clusters have been separately measured by this technique. The observed processes have been analysed by simple kinetic equations, taking into account the sink effect of surface and the defect clusters themselves together with the annihilation process due to thermal emission of vacancies from the defect clusters. Another tool to study time and temperature dependence of defect production in a cascade is computer simulation. Recent results of molecular dynamics calculations on the temperature dependence of cascade evolution are presented, including directional and temperature dependence of the lengths of replacement collision sequences, temperature dependence of the process to reach thermal equilibrium and so on. These results are discussed under general time frame of radiation damage evolution covering from 10 -15 to 10 9 s, and several important issues for the general understanding have been identified. (orig.)

A space and time scale-dependent nonlinear geostatistical approach for downscaling daily precipitation and temperature

KAUST Repository

Jha, Sanjeev Kumar

2015-07-21

A geostatistical framework is proposed to downscale daily precipitation and temperature. The methodology is based on multiple-point geostatistics (MPS), where a multivariate training image is used to represent the spatial relationship between daily precipitation and daily temperature over several years. Here, the training image consists of daily rainfall and temperature outputs from the Weather Research and Forecasting (WRF) model at 50 km and 10 km resolution for a twenty year period ranging from 1985 to 2004. The data are used to predict downscaled climate variables for the year 2005. The result, for each downscaled pixel, is daily time series of precipitation and temperature that are spatially dependent. Comparison of predicted precipitation and temperature against a reference dataset indicates that both the seasonal average climate response together with the temporal variability are well reproduced. The explicit inclusion of time dependence is explored by considering the climate properties of the previous day as an additional variable. Comparison of simulations with and without inclusion of time dependence shows that the temporal dependence only slightly improves the daily prediction because the temporal variability is already well represented in the conditioning data. Overall, the study shows that the multiple-point geostatistics approach is an efficient tool to be used for statistical downscaling to obtain local scale estimates of precipitation and temperature from General Circulation Models. This article is protected by copyright. All rights reserved.

Real-Time Wait-Free Queues using Micro-Transactions

OpenAIRE

Meawad, Fadi; Iyer, Karthik; Schoeberl, Martin; Vitek, Jan

2011-01-01

This paper evaluates the applicability of transactional mem- ory to the implementation of dierent non-blocking data structures in the context of the Real-time Specication for Java. In particular, we argue that hardware support for micro-transaction allows us to implement eciently data structures that are often dicult to realize with the atomic operations provided by stock hardware. Our main imple- mentation platform is the Java Optimized Processor sys- tem. We report on the performance of dat...

A real time measurement of junction temperature variation in high power IGBT modules for wind power converter application

DEFF Research Database (Denmark)

Ghimire, Pramod; Pedersen, Kristian Bonderup; de Vega, Angel Ruiz

2014-01-01

This paper presents a real time measurement of on-state forward voltage and estimating the junction temperature for a high power IGBT module during a power converter operation. The power converter is realized as it can be used for a wind turbine system. The peak of the junction temperature is dec...

Real-time studies of battery electrochemical reactions inside a transmission electron microscope.

Energy Technology Data Exchange (ETDEWEB)

Leung, Kevin; Hudak, Nicholas S.; Liu, Yang; Liu, Xiaohua H.; Fan, Hongyou; Subramanian, Arunkumar; Shaw, Michael J.; Sullivan, John Patrick; Huang, Jian Yu

2012-01-01

We report the development of new experimental capabilities and ab initio modeling for real-time studies of Li-ion battery electrochemical reactions. We developed three capabilities for in-situ transmission electron microscopy (TEM) studies: a capability that uses a nanomanipulator inside the TEM to assemble electrochemical cells with ionic liquid or solid state electrolytes, a capability that uses on-chip assembly of battery components on to TEM-compatible multi-electrode arrays, and a capability that uses a TEM-compatible sealed electrochemical cell that we developed for performing in-situ TEM using volatile battery electrolytes. These capabilities were used to understand lithiation mechanisms in nanoscale battery materials, including SnO{sub 2}, Si, Ge, Al, ZnO, and MnO{sub 2}. The modeling approaches used ab initio molecular dynamics to understand early stages of ethylene carbonate reduction on lithiated-graphite and lithium surfaces and constrained density functional theory to understand ethylene carbonate reduction on passivated electrode surfaces.

Mechanical properties and dependence with temperature of tetragonal polycrystalline zirconia materials

International Nuclear Information System (INIS)

Orange, G.

1986-01-01

Polycrystalline zirconia materials with a high content of metastable tetragonal phase have been obtained by pressureless sintering from experimental powders. Mechanical properties have been determined at room temperature and compared with similar materials. The fracture strength (σ /SUB f/ ) and fracture toughness (K /SUB 1c/ ) temperature dependence has been studied, in air environment up to 1000 0 C. Microstructure was studied by SEM examinations of fracture faces and TEM observations. Fracture toughness (of about 10 MPa √m at room temperature) decreases from 200 0 C to 800 0 C. The critical temperature (T /SUB c/ ) is estimated at 600 0 C. We observe an important decreases of fracture strength at 200 0 C. These mechanical properties are discussed on the basis of the stability of the tetragonal phase depending on additive content, grain size and temperature

A comparison of the real-time and the imaginary-time formalisms of finite temperature field theory for 2,3, and 4-point Green's functions

International Nuclear Information System (INIS)

Aurenche, P.; Becherrawy, T.

1991-07-01

The predictions of the real-time and the imaginary-time formalisms of Finite Temperature Field Theory is compared. Retarded and advanced amplitudes are constructed in the real-time formalism which are linear combinations of the usual time-ordered thermo-field dynamics amplitudes. These amplitudes can be easily compared to the various analytically continued amplitudes of the imaginary-time formalism. Explicit calculation of the 2,3 and 4-point Green's functions in φ 3 field theory is done in the one and two-loop approximations, and the compatibility of the two formalisms is shown. (author) 17 refs., 12 figs

An atomic orbital based real-time time-dependent density functional theory for computing electronic circular dichroism band spectra

Energy Technology Data Exchange (ETDEWEB)

Goings, Joshua J.; Li, Xiaosong, E-mail: xsli@uw.edu [Department of Chemistry, University of Washington, Seattle, Washington 98195 (United States)

2016-06-21

One of the challenges of interpreting electronic circular dichroism (ECD) band spectra is that different states may have different rotatory strength signs, determined by their absolute configuration. If the states are closely spaced and opposite in sign, observed transitions may be washed out by nearby states, unlike absorption spectra where transitions are always positive additive. To accurately compute ECD bands, it is necessary to compute a large number of excited states, which may be prohibitively costly if one uses the linear-response time-dependent density functional theory (TDDFT) framework. Here we implement a real-time, atomic-orbital based TDDFT method for computing the entire ECD spectrum simultaneously. The method is advantageous for large systems with a high density of states. In contrast to previous implementations based on real-space grids, the method is variational, independent of nuclear orientation, and does not rely on pseudopotential approximations, making it suitable for computation of chiroptical properties well into the X-ray regime.

Interrelated temperature dependence of bulk etch rate and track length saturation time in CR-39 detector

International Nuclear Information System (INIS)

Azooz, A.A.; Al-Jubbori, M.A.

2013-01-01

Highlights: • New empirical parameterization of CR-39 bulk etch rate. • Bulk etch rates measurements using two different methods give consistent results. • Temperature independence of track saturation length. • Two empirical relation between bulk etch rate and temperature are suggested. • Simple inverse relation between bulk etch rate and track saturation time. -- Abstract: Experimental measurements of the etching solution temperature dependence of bulk etch rate using two independent methods revealed a few interesting properties. It is found that while the track saturation length is independent of etching temperature, the etching time needed to reach saturation is strongly temperature-dependent. It is demonstrated that there is systematic simple inverse relation between track saturation time, and etching solution temperature. In addition, and although, the relation between the bulk etch rate and etching solution temperature can be reasonably described by a modified form of the Arrhenius equation, better fits can be obtained by another equation suggested in this work

Temperature dependence of 1H NMR relaxation time, T2, for intact and neoplastic plant tissues

Science.gov (United States)

Lewa, Czesław J.; Lewa, Maria

Temperature dependences of the spin-spin proton relaxation time, T2, have been shown for normal and tumorous tissues collected from kalus culture Nicotiana tabacum and from the plant Kalanchoe daigremontiana. For neoplastic plant tissues, time T2 was increased compared to that for intact plants, a finding similar to that for animal and human tissues. The temperature dependences obtained were compared to analogous relations observed with animal tissues.

Real-time systems

OpenAIRE

Badr, Salah M.; Bruztman, Donald P.; Nelson, Michael L.; Byrnes, Ronald Benton

1992-01-01

This paper presents an introduction to the basic issues involved in real-time systems. Both real-time operating sys and real-time programming languages are explored. Concurrent programming and process synchronization and communication are also discussed. The real-time requirements of the Naval Postgraduate School Autonomous Under Vehicle (AUV) are then examined. Autonomous underwater vehicle (AUV), hard real-time system, real-time operating system, real-time programming language, real-time sy...

Helicopter TEM parameters analysis and system optimization based on time constant

Science.gov (United States)

Xiao, Pan; Wu, Xin; Shi, Zongyang; Li, Jutao; Liu, Lihua; Fang, Guangyou

2018-03-01

Helicopter transient electromagnetic (TEM) method is a kind of common geophysical prospecting method, widely used in mineral detection, underground water exploration and environment investigation. In order to develop an efficient helicopter TEM system, it is necessary to analyze and optimize the system parameters. In this paper, a simple and quantitative method is proposed to analyze the system parameters, such as waveform, power, base frequency, measured field and sampling time. A wire loop model is used to define a comprehensive 'time constant domain' that shows a range of time constant, analogous to a range of conductance, after which the characteristics of the system parameters in this domain is obtained. It is found that the distortion caused by the transmitting base frequency is less than 5% when the ratio of the transmitting period to the target time constant is greater than 6. When the sampling time window is less than the target time constant, the distortion caused by the sampling time window is less than 5%. According to this method, a helicopter TEM system, called CASHTEM, is designed, and flight test has been carried out in the known mining area. The test results show that the system has good detection performance, verifying the effectiveness of the method.

Time-dependent radiolytic yields at room temperature and temperature-dependent absorption spectra of the solvated electrons in polyols

International Nuclear Information System (INIS)

Lin Mingzhang; Mostafavi, M.; Lampre, I.; Muroya, Y.; Katsumura, Y.

2007-01-01

The molar extinction coefficients at the absorption maximum of the solvated electron spectrum have been evaluated to be 900, 970, and 1000 mol -1 ·m 2 for 1,2-ethanediol (12ED), 1,2-propanediol (12PD), and 1,3-propanediol (13PD), respectively. These values are two-third or three-fourth of the value usually reported in the published report. Picosecond pulse radiolysis studies have aided in depicting the radiolytic yield of the solvated electron in these solvents as a function of time from picosecond to microsecond. The radiolytic yield in these viscous solvents is found to be strongly different from that of the water solution. The temperature dependent absorption spectra of the solvated electron in 12ED, 12PD, and 13PD have been also investigated. In all the three solvents, the optical spectra shift to the red with increasing temperature. While the shape of the spectra does not change in 13PD, a widening on the blue side of the absorption band is observed in 12ED and 12PD at elevated temperatures. (authors)

Strength and Anisotropy in Tournemire Shale: Temperature, Pressure and Time Dependences

Science.gov (United States)

Bonnelye, A.; Schubnel, A.; Zhi, G.; David, C.; Dick, P.

2017-12-01

Time and temperature dependent rock deformation has both scientific and socio-economic implications for natural hazards, the oil and gas industry and nuclear waste disposal. During the past decades, most studies on brittle creep have focused on igneous rocks and porous sedimentary rocks. To our knowledge, only few studies have been carried out on the brittle creep behavior of shale. We conducted a series of creep experiments on shale specimens coming from the French Institute for Nuclear Safety (IRSN) underground research laboratory located in Tournemire, France, under two different temperatures (26°C, 75°C) and confining pressures (10 MPa, 80 MPa), for three orientations (σ1along, perpendicular and 45° to bedding). In these long-term experiments (approximately 10 days), stress and strains were recorded continuously, while ultrasonic acoustic velocities were recorded every 1 15 minutes. The brittle creep failure stress of our Tournemire shale samples was systematically observed 50% higher than its short-term peak strength, with larger final axial strain accumulated. During creep, ultrasonic wave velocities first decreased, and then increased gradually. The magnitude of elastic wave velocity variations showed an important orientation and temperature dependence: velocities measured perpendicular to bedding showed increased variation, variation that was enhanced at higher temperature and higher pressure. The case of complete elastic anisotropy reversal was observed for sample deformed perpendicular to bedding, with amount of axial strain needed to reach anisotropy reversal reduced at higher temperature. SEM observations highlight the competition between crack growth, sealing/healing, and possibly mineral rotation, pressure solution or anisotropic compaction during creep defromation. Our study highlights that the short-term peak strength has little meaning in shale material, which can over-consolidate importantly by `plastic' flow. In addition, we show that elastic

Real-time modeling of heat distributions

Science.gov (United States)

Hamann, Hendrik F.; Li, Hongfei; Yarlanki, Srinivas

2018-01-02

Techniques for real-time modeling temperature distributions based on streaming sensor data are provided. In one aspect, a method for creating a three-dimensional temperature distribution model for a room having a floor and a ceiling is provided. The method includes the following steps. A ceiling temperature distribution in the room is determined. A floor temperature distribution in the room is determined. An interpolation between the ceiling temperature distribution and the floor temperature distribution is used to obtain the three-dimensional temperature distribution model for the room.

The Temperature Condition of the Plate with Temperature-Dependent Thermal Conductivity and Energy Release

Directory of Open Access Journals (Sweden)

V. S. Zarubin

2016-01-01

Full Text Available The temperature state of a solid body, in addition to the conditions of its heat exchange with the environment, can greatly depend on the heat release (or heat absorption processes within the body volume. Among the possible causes of these processes should be noted such as a power release in the fuel elements of nuclear reactors, exothermic or endothermic chemical reactions in the solid body material, which respectively involve heat release or absorbtion, heat transfer of a part of the electric power in the current-carrying conductors (so-called Joule’s heat or the energy radiation penetrating into the body of a semitransparent material, etc. The volume power release characterizes an intensity of these processes.The extensive list of references to the theory of heat conductivity of solids offers solutions to problems to determine a stationary (steady over time and non-stationary temperature state of the solids (as a rule, of the canonical form, which act as the sources of volume power release. Thus, in general case, a possibility for changing power release according to the body volume and in solving the nonstationary problems also a possible dependence of this value on the time are taken into consideration.However, in real conditions the volume power release often also depends on the local temperature, and such dependence can be nonlinear. For example, with chemical reactions the intensity of heat release or absorption is in proportion to their rate, which, in turn, is sensitive to the temperature value, and a dependence on the temperature is exponential. A further factor that in such cases makes the analysis of the solid temperature state complicated, is dependence on the temperature and the thermal conductivity of this body material, especially when temperature distribution therein  is significantly non-uniform. Taking into account the influence of these factors requires the mathematical modeling methods, which allow us to build an adequate

Global gyrokinetic simulations of TEM microturbulence

Science.gov (United States)

Vernay, T.; Brunner, S.; Villard, L.; McMillan, B. F.; Jolliet, S.; Bottino, A.; Görler, T.; Jenko, F.

2013-07-01

Global gyrokinetic simulations of electrostatic temperature-gradient-driven trapped-electron-mode (TEM) turbulence using the δf particle-in-cell code ORB5 are presented. The electron response is either fully kinetic or hybrid, i.e. considering kinetic trapped and adiabatic passing electrons. A linear benchmark in the TEM regime against the Eulerian-based code GENE is presented. Two different methods for controlling the numerical noise, based, respectively, on a Krook operator and a so-called coarse-graining approach, are discussed and successfully compared. Both linear and non-linear studies are carried out for addressing the issue of finite-ρ*-effects and finite electron collisionality on TEM turbulence. Electron collisions are found to damp TEMs through the detrapping process, while finite-ρ*-effects turn out to be important in the non-linear regime but very small in the linear regime. Finally, the effects of zonal flows on TEM turbulence are briefly considered as well and shown to be unimportant in the temperature-gradient-driven TEM regime. Consistently, basically no difference is found between linear and non-linear critical electron temperature gradients in the TEM regime.

Microstructural studies of 35 degrees C copper Ni-Ti orthodontic wire and TEM confirmation of low-temperature martensite transformation.

Science.gov (United States)

Brantley, William A; Guo, Wenhua; Clark, William A T; Iijima, Masahiro

2008-02-01

Previous temperature-modulated differential scanning calorimetry (TMDSC) study of nickel-titanium orthodontic wires revealed a large exothermic low-temperature peak that was attributed to transformation within martensitic NiTi. The purpose of this study was to use transmission electron microscopy (TEM) to verify this phase transformation in a clinically popular nickel-titanium wire, identify its mechanism and confirm other phase transformations found by TMDSC, and to provide detailed information about the microstructure of this wire. The 35 degrees C Copper nickel-titanium wire (Ormco) with cross-section dimensions of 0.016 in. x 0.022 in. used in the earlier TMDSC investigation was selected. Foils were prepared for TEM analyses by mechanical grinding, polishing, dimpling, ion milling and plasma cleaning. Standard bright-field and dark-field TEM images were obtained, along with convergent-beam electron diffraction patterns. A cryo-stage with the electron microscope (Phillips CM 200) permitted the specimen to be observed at -187, -45, and 50 degrees C, as well as at room temperature. Microstructures were also observed with an optical microscope and a scanning electron microscope. Room temperature microstructures had randomly oriented, elongated grains that were twinned. Electron diffraction patterns confirmed that phase transformations took place over temperature ranges previously found by TMDSC. TEM observations revealed a high dislocation density and fine-scale oxide particles, and that twinning is the mechanism for the low-temperature transformation in martensitic NiTi. TEM confirmed the low-temperature peak and other phase transformations observed by TMDSC, and revealed that twinning in martensite is the mechanism for the low-temperature peak. The high dislocation density and fine-scale oxide particles in the microstructure are the result of the wire manufacturing process.

Objective function analysis for electric soundings (VES), transient electromagnetic soundings (TEM) and joint inversion VES/TEM

Science.gov (United States)

Bortolozo, Cassiano Antonio; Bokhonok, Oleg; Porsani, Jorge Luís; Monteiro dos Santos, Fernando Acácio; Diogo, Liliana Alcazar; Slob, Evert

2017-11-01

Ambiguities in geophysical inversion results are always present. How these ambiguities appear in most cases open to interpretation. It is interesting to investigate ambiguities with regard to the parameters of the models under study. Residual Function Dispersion Map (RFDM) can be used to differentiate between global ambiguities and local minima in the objective function. We apply RFDM to Vertical Electrical Sounding (VES) and TEM Sounding inversion results. Through topographic analysis of the objective function we evaluate the advantages and limitations of electrical sounding data compared with TEM sounding data, and the benefits of joint inversion in comparison with the individual methods. The RFDM analysis proved to be a very interesting tool for understanding the joint inversion method of VES/TEM. Also the advantage of the applicability of the RFDM analyses in real data is explored in this paper to demonstrate not only how the objective function of real data behaves but the applicability of the RFDM approach in real cases. With the analysis of the results, it is possible to understand how the joint inversion can reduce the ambiguity of the methods.

Near-real-time feedback control system for liver thermal ablations based on self-referenced temperature imaging

International Nuclear Information System (INIS)

Keserci, Bilgin M.; Kokuryo, Daisuke; Suzuki, Kyohei; Kumamoto, Etsuko; Okada, Atsuya; Khankan, Azzam A.; Kuroda, Kagayaki

2006-01-01

Our challenge was to design and implement a dedicated temperature imaging feedback control system to guide and assist in a thermal liver ablation procedure in a double-donut 0.5T open MR scanner. This system has near-real-time feedback capability based on a newly developed 'self-referenced' temperature imaging method using 'moving-slab' and complex-field-fitting techniques. Two phantom validation studies and one ex vivo experiment were performed to compare the newly developed self-referenced method with the conventional subtraction method and evaluate the ability of the feedback control system in the same MR scanner. The near-real-time feedback system was achieved by integrating the following primary functions: (1) imaging of the moving organ temperature; (2) on-line needle tip tracking; (3) automatic turn-on/off the heating devices; (4) a Windows operating system-based novel user-interfaces. In the first part of the validation studies, microwave heating was applied in an agar phantom using a fast spoiled gradient recalled echo in a steady state sequence. In the second part of the validation and ex vivo study, target visualization, treatment planning and monitoring, and temperature and thermal dose visualization with the graphical user interface of the thermal ablation software were demonstrated. Furthermore, MR imaging with the 'self-referenced' temperature imaging method has the ability to localize the hot spot in the heated region and measure temperature elevation during the experiment. In conclusion, we have demonstrated an interactively controllable feedback control system that offers a new method for the guidance of liver thermal ablation procedures, as well as improving the ability to assist ablation procedures in an open MR scanner

Real-Time Wait-Free Queues using Micro-Transactions

DEFF Research Database (Denmark)

Meawad, Fadi; Iyer, Karthik; Schoeberl, Martin

2011-01-01

This paper evaluates the applicability of transactional mem- ory to the implementation of dierent non-blocking data structures in the context of the Real-time Specication for Java. In particular, we argue that hardware support for micro-transaction allows us to implement eciently data structures...... that are often dicult to realize with the atomic operations provided by stock hardware. Our main imple- mentation platform is the Java Optimized Processor sys- tem. We report on the performance of data structures imple- mented with locks, compare and swap and micro-transactions. Our results conrm...

Real-time trichromatic holographic interferometry: preliminary study

Science.gov (United States)

Albe, Felix; Bastide, Myriam; Desse, Jean-Michel; Tribillon, Jean-Louis H.

1998-08-01

In this paper we relate our preliminary experiments on real- time trichromatic holographic interferometry. For this purpose a CW `white' laser (argon and krypton of Coherent- Radiation, Spectrum model 70) is used. This laser produces about 10 wavelengths. A system consisting of birefringent plates and polarizers allows to select a trichromatic TEM00 triplet: blue line ((lambda) equals 476 nm, 100 mW), green line ((lambda) equals 514 nm, 100 mW) and red line ((lambda) equals 647 nm, 100 mW). In a first stage we recorded a trichromatic reflection hologram with a separate reference beam on a single-layer silver-halide panchromatic plate (PFG 03C). After processing, the hologram is put back into the original recording set-up, as in classical experiments on real-time monochromatic holographic interferometry. So we observe interference fringes between the 3 reconstructed waves and the 3 actual waves. The interference fringes of the phenomenon are observed on a screen and recorded by a video camera at 25 frames per second. A color video film of about 3 minutes of duration is presented. Some examples related to phase objects are presented (hot airflow from a candle, airflow from a hand). The actual results show the possibility of using this technique to study, in real time, aerodynamic wakes and mechanical deformation.

A proton-recoil neutron spectrometer for time-dependent ion temperatures on the National Ignition Facility

International Nuclear Information System (INIS)

Murphy, T.J.

1995-01-01

Ion temperatures from inertial confinement fusion targets are usually determined by measuring the Doppler broadening of the neutron spectrum using the time-of-flight method. Measurement systems are generally designed so that the contribution of the duration of neutron production (∼100 ps) to the width of the neutron signal is negligible. This precludes the possibility of time-dependent ion temperature. If, however, one could measure the neutron energy and arrival time at a detector independently, then time-dependent neutron spectra could be obtained, and ion temperature information deduced. A concept utilizing a proton-recoil neutron spectrometer has been developed in which recoil protons from a small plastic foil are measured. From the energy, arrival time, and recoil angle of the recoil proton, the birth time and energy of the incident neutron can be deduced. The sensitivity of the system is low, but the higher anticipated neutron yields from the proposed National Ignition Facility may make the technique feasible. Large scintillator arrays currently in use on the Nova facility for neutron spectral measurements consist of ∼1,000 channels and detect between 50 and 500 counts for typical time-integrated data. Time-dependent results would then require about an order of magnitude larger system. Key issues for making this system feasible will be keeping the cost per channel low while allowing adequately time (∼ 50 ps), energy (20 keV), and angular resolution (2 mrad) for each of the proton detectors

Real-time x-ray scattering study of the initial growth of organic crystals on polymer brushes

Energy Technology Data Exchange (ETDEWEB)

An, Sung Yup; Ahn, Kwangseok; Kim, Doris Yangsoo; Lee, Dong Ryeol, E-mail: drlee@ssu.ac.kr [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of); Lee, Hyun-Hwi [Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang 790-784 (Korea, Republic of); Cho, Jeong Ho, E-mail: jhcho94@skku.edu [Department of Chemical Engineering, SKKU Advanced Institute of Nanotechnology (SAINT) and Center for Human Interface Nano Technology (HINT), Sungkyunkwan University, Suwon 440-476 (Korea, Republic of)

2014-04-21

We studied the early-stage growth structures of pentacene organic crystals grown on polymer brushes using real-time x-ray scattering techniques. In situ x-ray reflectivity and atomic force microscopy analyses revealed that at temperatures close to the glass transition temperature of polymer brush, the pentacene overlayer on a polymer brush film showed incomplete condensation and 3D island structures from the first monolayer. A growth model based on these observations was used to quantitatively analyze the real-time anti-Bragg x-ray scattering intensities measured during pentacene growth to obtain the time-dependent layer coverage of the individual pentacene monolayers. The extracted total coverage confirmed significant desorption and incomplete condensation in the pentacene films deposited on the polymer brushes. These effects are ascribed to the change in the surface viscoelasticity of the polymer brushes around the glass transition temperature.

Real time psychrometric data collection

International Nuclear Information System (INIS)

McDaniel, K.H.

1996-01-01

Eight Mine Weather Stations (MWS) installed at the Waste Isolation Pilot Plant (WIPP) to monitor the underground ventilation system are helping to simulate real-time ventilation scenarios. Seasonal weather extremes can result in variations of Natural Ventilation Pressure (NVP) which can significantly effect the ventilation system. The eight MWS(s) (which previously collected and stored temperature, barometric pressure and relative humidity data for subsequent NVP calculations) were upgraded to provide continuous real-time data to the site wide Central monitoring System. This data can now be utilized by the ventilation engineer to create realtime ventilation simulations and trends which assist in the prediction and mitigation of NVP and psychrometric related events

Scattering of a TEM wave from a time varying surface

Science.gov (United States)

Elcrat, Alan R.; Harder, T. Mark; Stonebraker, John T.

1990-03-01

A solution is given for reflection of a plane wave with TEM polarization from a planar surface with time varying properties. These properties are given in terms of the currents on the surface. The solution is obtained by numerically solving a system of differential-delay equations in the time domain.

Regional dependence in earthquake early warning and real time seismology

International Nuclear Information System (INIS)

Caprio, M.

2013-01-01

An effective earthquake prediction method is still a Chimera. What we can do at the moment, after the occurrence of a seismic event, is to provide the maximum available information as soon as possible. This can help in reducing the impact of the quake on population or and better organize the rescue operations in case of post-event actions. This study strives to improve the evaluation of earthquake parameters shortly after the occurrence of a major earthquake, and the characterization of regional dependencies in Real-Time Seismology. The recent earthquake experience from Tohoku (M 9.0, 11.03.2011) showed how an efficient EEW systems can inform numerous people and thus potentially reduce the economic and human losses by distributing warning messages several seconds before the arrival of seismic waves. In the case of devastating earthquakes, usually, in the first minutes to days after the main shock, the common communications channels can be overloaded or broken. In such cases, a precise knowledge of the macroseismic intensity distribution will represent a decisive contribution in help management and in the valuation of losses. In this work, I focused on improving the adaptability of EEW systems (chapters 1 and 2) and in deriving a global relationship for converting peak ground motion into macroseismic intensity and vice versa (chapter 3). For EEW applications, in chapter 1 we present an evolutionary approach for magnitude estimation for earthquake early warning based on real-time inversion of displacement spectra. The Spectrum Inversion (SI) method estimates magnitude and its uncertainty by inferring the shape of the entire displacement spectral curve based on the part of the spectra constrained by available data. Our method can be applied in any region without the need for calibration. SI magnitude and uncertainty estimates are updated each second following the initial P detection and potentially stabilize within 10 seconds from the initial earthquake detection

Regional dependence in earthquake early warning and real time seismology

Energy Technology Data Exchange (ETDEWEB)

Caprio, M.

2013-07-01

An effective earthquake prediction method is still a Chimera. What we can do at the moment, after the occurrence of a seismic event, is to provide the maximum available information as soon as possible. This can help in reducing the impact of the quake on population or and better organize the rescue operations in case of post-event actions. This study strives to improve the evaluation of earthquake parameters shortly after the occurrence of a major earthquake, and the characterization of regional dependencies in Real-Time Seismology. The recent earthquake experience from Tohoku (M 9.0, 11.03.2011) showed how an efficient EEW systems can inform numerous people and thus potentially reduce the economic and human losses by distributing warning messages several seconds before the arrival of seismic waves. In the case of devastating earthquakes, usually, in the first minutes to days after the main shock, the common communications channels can be overloaded or broken. In such cases, a precise knowledge of the macroseismic intensity distribution will represent a decisive contribution in help management and in the valuation of losses. In this work, I focused on improving the adaptability of EEW systems (chapters 1 and 2) and in deriving a global relationship for converting peak ground motion into macroseismic intensity and vice versa (chapter 3). For EEW applications, in chapter 1 we present an evolutionary approach for magnitude estimation for earthquake early warning based on real-time inversion of displacement spectra. The Spectrum Inversion (SI) method estimates magnitude and its uncertainty by inferring the shape of the entire displacement spectral curve based on the part of the spectra constrained by available data. Our method can be applied in any region without the need for calibration. SI magnitude and uncertainty estimates are updated each second following the initial P detection and potentially stabilize within 10 seconds from the initial earthquake detection

Real-time dynamics of matrix quantum mechanics beyond the classical approximation

Science.gov (United States)

Buividovich, Pavel; Hanada, Masanori; Schäfer, Andreas

2018-03-01

We describe a numerical method which allows to go beyond the classical approximation for the real-time dynamics of many-body systems by approximating the many-body Wigner function by the most general Gaussian function with time-dependent mean and dispersion. On a simple example of a classically chaotic system with two degrees of freedom we demonstrate that this Gaussian state approximation is accurate for significantly smaller field strengths and longer times than the classical one. Applying this approximation to matrix quantum mechanics, we demonstrate that the quantum Lyapunov exponents are in general smaller than their classical counterparts, and even seem to vanish below some temperature. This behavior resembles the finite-temperature phase transition which was found for this system in Monte-Carlo simulations, and ensures that the system does not violate the Maldacena-Shenker-Stanford bound λL < 2πT, which inevitably happens for classical dynamics at sufficiently small temperatures.

Nonadiabatic Dynamics for Electrons at Second-Order: Real-Time TDDFT and OSCF2.

Science.gov (United States)

Nguyen, Triet S; Parkhill, John

2015-07-14

We develop a new model to simulate nonradiative relaxation and dephasing by combining real-time Hartree-Fock and density functional theory (DFT) with our recent open-systems theory of electronic dynamics. The approach has some key advantages: it has been systematically derived and properly relaxes noninteracting electrons to a Fermi-Dirac distribution. This paper combines the new dissipation theory with an atomistic, all-electron quantum chemistry code and an atom-centered model of the thermal environment. The environment is represented nonempirically and is dependent on molecular structure in a nonlocal way. A production quality, O(N(3)) closed-shell implementation of our theory applicable to realistic molecular systems is presented, including timing information. This scaling implies that the added cost of our nonadiabatic relaxation model, time-dependent open self-consistent field at second order (OSCF2), is computationally inexpensive, relative to adiabatic propagation of real-time time-dependent Hartree-Fock (TDHF) or time-dependent density functional theory (TDDFT). Details of the implementation and numerical algorithm, including factorization and efficiency, are discussed. We demonstrate that OSCF2 approaches the stationary self-consistent field (SCF) ground state when the gap is large relative to k(b)T. The code is used to calculate linear-response spectra including the effects of bath dynamics. Finally, we show how our theory of finite-temperature relaxation can be used to correct ground-state DFT calculations.

Study on APD real time compensation methods of laser Detection system

International Nuclear Information System (INIS)

Feng Ying; Zhang He; Zhang Xiangjin; Liu Kun

2011-01-01

their operating principles. The constant false alarm rate compensation can't detect the pulse signal which comes randomly. Therefore real-time performance can't be realized. The noise compensation can meet the request of real-time performance. If it is used in the environment where background light is intense or changes acutely, there is a better effect. The temperature compensation can also achieve the real-time performance request. If it is used in the environment where temperature changes acutely, there is also a better effect. Aim at such problems, this paper presents that different APD real-time compensations should be adopt to adapt to different environments. The exiting temperature compensation adjusts output voltage by using variable resistance to regulate input voltage. Its structure is complex; the real-time performance is worse. In order to remedy these defects, a real-time temperature compensation which is based on switch on-off time of switching power supply is designed. Its feasibility and operating stability are confirmed by plate making and experiment. At last, the comparison experiments between the real-time noise compensation and the real-time temperature compensation is carried out in the environments where temperature is almost invariant and background light acutely changes from5lux to150lux . The result shows that the operating effect of the real-time noise compensation is better here, the noise minifies to a sixth of original noise. The comparison experiments between the real-time noise compensation and the real-time temperature compensation is carried out in darkroom where background light is 5lux and temperature almost rapidly changes from -20 deg. C to 80 deg. C. The result shows that the operating effect of the real-time temperature compensation is better here, the noise minifies to a seventh of original noise. Moreover, these methods can be applied to other type detection systems of weak photoelectric signal; they have high actual application

Study on APD real time compensation methods of laser Detection system

Energy Technology Data Exchange (ETDEWEB)

Feng Ying; Zhang He; Zhang Xiangjin; Liu Kun, E-mail: fy_caimi@163.com [ZNDY of Ministerial Key Laboratory, Nanjing University of Science and Technology, Nanjing 210094 (China)

2011-02-01

by analyzing their operating principles. The constant false alarm rate compensation can't detect the pulse signal which comes randomly. Therefore real-time performance can't be realized. The noise compensation can meet the request of real-time performance. If it is used in the environment where background light is intense or changes acutely, there is a better effect. The temperature compensation can also achieve the real-time performance request. If it is used in the environment where temperature changes acutely, there is also a better effect. Aim at such problems, this paper presents that different APD real-time compensations should be adopt to adapt to different environments. The exiting temperature compensation adjusts output voltage by using variable resistance to regulate input voltage. Its structure is complex; the real-time performance is worse. In order to remedy these defects, a real-time temperature compensation which is based on switch on-off time of switching power supply is designed. Its feasibility and operating stability are confirmed by plate making and experiment. At last, the comparison experiments between the real-time noise compensation and the real-time temperature compensation is carried out in the environments where temperature is almost invariant and background light acutely changes from5lux to150lux . The result shows that the operating effect of the real-time noise compensation is better here, the noise minifies to a sixth of original noise. The comparison experiments between the real-time noise compensation and the real-time temperature compensation is carried out in darkroom where background light is 5lux and temperature almost rapidly changes from -20 deg. C to 80 deg. C. The result shows that the operating effect of the real-time temperature compensation is better here, the noise minifies to a seventh of original noise. Moreover, these methods can be applied to other type detection systems of weak photoelectric signal; they

Study on APD real time compensation methods of laser Detection system

Science.gov (United States)

Ying, Feng; He, Zhang; Xiangjin, Zhang; Kun, Liu

2011-02-01

their operating principles. The constant false alarm rate compensation can't detect the pulse signal which comes randomly. Therefore real-time performance can't be realized. The noise compensation can meet the request of real-time performance. If it is used in the environment where background light is intense or changes acutely, there is a better effect. The temperature compensation can also achieve the real-time performance request. If it is used in the environment where temperature changes acutely, there is also a better effect. Aim at such problems, this paper presents that different APD real-time compensations should be adopt to adapt to different environments. The exiting temperature compensation adjusts output voltage by using variable resistance to regulate input voltage. Its structure is complex; the real-time performance is worse. In order to remedy these defects, a real-time temperature compensation which is based on switch on-off time of switching power supply is designed. Its feasibility and operating stability are confirmed by plate making and experiment. At last, the comparison experiments between the real-time noise compensation and the real-time temperature compensation is carried out in the environments where temperature is almost invariant and background light acutely changes from5lux to150lux . The result shows that the operating effect of the real-time noise compensation is better here, the noise minifies to a sixth of original noise. The comparison experiments between the real-time noise compensation and the real-time temperature compensation is carried out in darkroom where background light is 5lux and temperature almost rapidly changes from -20°C to 80°C. The result shows that the operating effect of the real-time temperature compensation is better here, the noise minifies to a seventh of original noise. Moreover, these methods can be applied to other type detection systems of weak photoelectric signal; they have high actual application value.

Tradeoff analysis for Dependable Real-Time Embedded Systems during the Early Design Phases

DEFF Research Database (Denmark)

Gan, Junhe

Embedded systems are becoming increasingly complex and have tight competing constraints in terms of performance, cost, energy consumption, dependability, flexibility, security, etc. The objective of this thesis is to propose design methods and tools for supporting the tradeoff analysis of competing...... to processing elements, as well as the processor voltage and frequency levels for executing each task, such that transient faults are tolerated, the real-time constraints of the application are satisfied, and the energy consumed is minimized. In this thesis, we target the early design phases, when decisions...... have a high impact on the subsequent implementation choices. However, due to a lack of information, the early design phases are characterized by uncertainties, e.g., in the worst-case execution times (WCETs), in the functionality requirements, or in the hardware component costs. In this context, we...

Application of the Real-Time Time-Dependent Density Functional Theory to Excited-State Dynamics of Molecules and 2D Materials

Science.gov (United States)

Miyamoto, Yoshiyuki; Rubio, Angel

2018-04-01

We review our recent developments in the ab initio simulation of excited-state dynamics within the framework of time-dependent density functional theory (TDDFT). Our targets range from molecules to 2D materials, although the methods are general and can be applied to any other finite and periodic systems. We discuss examples of excited-state dynamics obtained by real-time TDDFT coupled with molecular dynamics (MD) and the Ehrenfest approximation, including photoisomerization in molecules, photoenhancement of the weak interatomic attraction of noble gas atoms, photoenhancement of the weak interlayer interaction of 2D materials, pulse-laser-induced local bond breaking of adsorbed atoms on 2D sheets, modulation of UV light intensity by graphene nanoribbons at terahertz frequencies, and collision of high-speed ions with the 2D material to simulate the images taken by He ion microscopy. We illustrate how the real-time TDDFT approach is useful for predicting and understanding non-equilibrium dynamics in condensed matter. We also discuss recent developments that address the excited-state dynamics of systems out of equilibrium and future challenges in this fascinating field of research.

Power minimisation for real-time dataflow applications.

NARCIS (Netherlands)

Nelson, Andrew; Moreira, O.; Molnos, A.M.; Stuijk, S.; Nguyen, B.T.; Goossens, K.G.W.; Kitsos, P.

2011-01-01

Energy efficient execution of applications is important for many reasons, e.g. time between battery charges, device temperature. Voltage and Frequency Scaling (VFS) enables applications to be run at lower frequencies on hardware resources thereby consuming less power. Real-time applications have

Real-Time Prediction of Temperature Elevation During Robotic Bone Drilling Using the Torque Signal.

Science.gov (United States)

Feldmann, Arne; Gavaghan, Kate; Stebinger, Manuel; Williamson, Tom; Weber, Stefan; Zysset, Philippe

2017-09-01

Bone drilling is a surgical procedure commonly required in many surgical fields, particularly orthopedics, dentistry and head and neck surgeries. While the long-term effects of thermal bone necrosis are unknown, the thermal damage to nerves in spinal or otolaryngological surgeries might lead to partial paralysis. Previous models to predict the temperature elevation have been suggested, but were not validated or have the disadvantages of computation time and complexity which does not allow real time predictions. Within this study, an analytical temperature prediction model is proposed which uses the torque signal of the drilling process to model the heat production of the drill bit. A simple Green's disk source function is used to solve the three dimensional heat equation along the drilling axis. Additionally, an extensive experimental study was carried out to validate the model. A custom CNC-setup with a load cell and a thermal camera was used to measure the axial drilling torque and force as well as temperature elevations. Bones with different sets of bone volume fraction were drilled with two drill bits ([Formula: see text]1.8 mm and [Formula: see text]2.5 mm) and repeated eight times. The model was calibrated with 5 of 40 measurements and successfully validated with the rest of the data ([Formula: see text]C). It was also found that the temperature elevation can be predicted using only the torque signal of the drilling process. In the future, the model could be used to monitor and control the drilling process of surgeries close to vulnerable structures.

Nonlinear entropy transfer in ETG-TEM turbulence via TEM driven zonal flows

International Nuclear Information System (INIS)

Asahi, Yuuichi; Tsutsui, Hiroaki; Tsuji-Iio, Shunji; Ishizawa, Akihiro; Sugama, Hideo; Watanabe, Tomohiko

2015-01-01

Nonlinear interplay of the electron temperature gradient (ETG) modes and the trapped electron modes (TEMs) was investigated by means of gyrokinetic simulation. Focusing on the situation where both TEMs and ETG modes are linearly unstable, the effects of TEM-driven zonal flows on ETG turbulence were examined by means of entropy transfer analysis. In a statistically steady turbulence where the TEM driven zonal flows are dominant, it turned out that the zonal flows meditate the entropy transfer of the ETG modes from the low to high radial wavenumber regions. The successive entropy transfer broadens the potential fluctuation spectrum in the radial wavenumber direction. In contrast, in the situation where ETG modes are unstable but TEMs are stable, the pure ETG turbulence does not produce strong zonal flows, leading to a rather narrow spectrum in the radial wavenumber space and a higher transport level. (author)

Visualising reacting single atoms under controlled conditions: Advances in atomic resolution in situ Environmental (Scanning) Transmission Electron Microscopy (E(S)TEM)

Science.gov (United States)

Boyes, Edward D.; Gai, Pratibha L.

2014-02-01

Advances in atomic resolution Environmental (Scanning) Transmission Electron Microscopy (E(S)TEM) for probing gas-solid catalyst reactions in situ at the atomic level under controlled reaction conditions of gas environment and temperature are described. The recent development of the ESTEM extends the capability of the ETEM by providing the direct visualisation of single atoms and the atomic structure of selected solid state heterogeneous catalysts in their working states in real-time. Atomic resolution E(S)TEM provides a deeper understanding of the dynamic atomic processes at the surface of solids and their mechanisms of operation. The benefits of atomic resolution-E(S)TEM to science and technology include new knowledge leading to improved technological processes with substantial economic benefits, improved healthcare, reductions in energy needs and the management of environmental waste generation. xml:lang="fr"

Real-time measurement and control at Jet. Experiment Control

International Nuclear Information System (INIS)

Felton, R.; Zabeo, L.; Sartori, F.; Piccolo, F.; Farthing, J.; Budd, T.; Dorling, S.; McCullen, P.; Harling, J.; Dalley, S.; Goodyear, A.; Stephen, A.; Card, P.; Bright, M.; Lucock, R.; Jones, E.; Griph, S.; Hogben, C.; Beldishevski, M.; Buckley, M.; Davis, J.; Young, I.; Hemming, O.; Wheatley, M.; Heesterman, P.; Lloyd, G.; Walters, M.; Bridge, R.; Leggate, H.; Howell, D.; Zastrow, K.D.; Giroud, C.; Coffey, I.; Hawkes, N.; Stamp, M.; Barnsley, R.; Edlington, T.; Guenther, K.; Gowers, C.; Popovichef, S.; Huber, A.; Ingesson, C.; Joffrin, E.; Mazon, D.; Moreau, D.; Murari, A.; Riva, M.; Barana, O.; Bolzonella, T.; Valisa, M.; Innocente, P.; Zerbini, M.; Bosak, K.; Blum, J.; Vitale, E.; Crisanti, F.; La Luna, E. de; Sanchez, J.

2004-01-01

Over the past few ears, the preparation of ITER-relevant plasma scenarios has been the main focus experimental activity on tokamaks. The development of integrated, simultaneous, real-time controls of plasma shape, current, pressure, temperature, radiation, neutron profiles, and also impurities, ELMs (edge localized modes) and MHD are now seen to be essential for further development of quasi-steady state conditions with feedback, or the stabilisation of transient phenomena with event-driven actions. For this thrust, the EFDA JET Real Time Project has developed a set of real-time plasma measurements, experiment control, and communication facilities. The Plasma Diagnostics used for real-time experiments are Far Infra Red interferometry, polarimetry, visible, UV and X-ray spectroscopy, LIDAR, bolometry, neutron and magnetics. Further analysis systems produce integrated results such as temperature profiles on geometry derived from MHD equilibrium solutions. The Actuators include toroidal, poloidal and divertor coils, gas and pellet fuelling, neutral beam injection, radiofrequency (ICRH) waves and microwaves (LH). The Heating/Fuelling Operators can either define a power or gas request waveform or select the real-time instantaneous power/gas request from the Real Time Experiment Central Control (RTCC) system. The Real Time Experiment Control system provides both a high-level, control-programming environment and interlocks with the actuators. A MATLAB facility is being developed for the development of more complex controllers. The plasma measurement, controller and plant control systems communicate in ATM network. The EFDA Real Time project is essential groundwork for future reactors such as ITER. It involves many staff from several institutions. The facility is now frequently used in experiments. (authors)

Surface Temperature Variation Prediction Model Using Real-Time Weather Forecasts

Science.gov (United States)

Karimi, M.; Vant-Hull, B.; Nazari, R.; Khanbilvardi, R.

2015-12-01

by regression of weather variables. In addition amplitude of spatial variations were most dependent on temperature, north winds, and high level lapse rate and the temporal variations were most dependent on temperature and lapse rates.

Real Time Revisited

Science.gov (United States)

Allen, Phillip G.

1985-12-01

The call for abolishing photo reconnaissance in favor of real time is once more being heard. Ten years ago the same cries were being heard with the introduction of the Charge Coupled Device (CCD). The real time system problems that existed then and stopped real time proliferation have not been solved. The lack of an organized program by either DoD or industry has hampered any efforts to solve the problems, and as such, very little has happened in real time in the last ten years. Real time is not a replacement for photo, just as photo is not a replacement for infra-red or radar. Operational real time sensors can be designed only after their role has been defined and improvements made to the weak links in the system. Plodding ahead on a real time reconnaissance suite without benefit of evaluation of utility will allow this same paper to be used ten years from now.

Watching excitons move: the time-dependent transition density matrix

Science.gov (United States)

Ullrich, Carsten

2012-02-01

Time-dependent density-functional theory allows one to calculate excitation energies and the associated transition densities in principle exactly. The transition density matrix (TDM) provides additional information on electron-hole localization and coherence of specific excitations of the many-body system. We have extended the TDM concept into the real-time domain in order to visualize the excited-state dynamics in conjugated molecules. The time-dependent TDM is defined as an implicit density functional, and can be approximately obtained from the time-dependent Kohn-Sham orbitals. The quality of this approximation is assessed in simple model systems. A computational scheme for real molecular systems is presented: the time-dependent Kohn-Sham equations are solved with the OCTOPUS code and the time-dependent Kohn-Sham TDM is calculated using a spatial partitioning scheme. The method is applied to show in real time how locally created electron-hole pairs spread out over neighboring conjugated molecular chains. The coupling mechanism, electron-hole coherence, and the possibility of charge separation are discussed.

Some contributions towards the parallel simulation of time dependent neutron transport and the integration of observed data in real time

International Nuclear Information System (INIS)

Mula-Hernandez, Olga

2014-01-01

In this thesis, we have first developed a time dependent 3D neutron transport solver on unstructured meshes with discontinuous Galerkin finite elements spatial discretization. The solver (called MINARET) represents in itself an important contribution in reactor physics thanks to the accuracy that it can provide in the knowledge of the state of the core during severe accidents. It will also play an important role on vessel fluence calculations. From a mathematical point of view, the most important contribution has consisted in the implementation of modern algorithms that are well adapted for modern parallel architectures and that significantly decrease the computing times. A special effort has been done in order to efficiently parallelize the time variable by the use of the parareal in time algorithm. For this, we have first analyzed the performances that the classical scheme of parareal can provide when applied to the resolution of the neutron transport equation in a reactor core. Then, with the purpose of improving these performances, a parareal scheme that takes more efficiently into account the presence of other iterative schemes in the resolution of each time step has been proposed. The main idea consists in limiting the number of internal iterations for each time step and to reach convergence across the parareal iterations. A second phase of our work has been motivated by the following question: given the high degree of accuracy that MINARET can provide in the modeling of the neutron population, could we somehow use it as a tool to monitor in real time the population of neutrons on the purpose of helping in the operation of the reactor? And, what is more, how to make such a tool be coherent in some sense with the measurements taken in situ? One of the main challenges of this problem is the real time aspect of the simulations. Indeed, despite all of our efforts to speed-up the calculations, the discretization methods used in MINARET do not provide simulations

Application of radio frequency based digital thermometer for real-time monitoring of dairy cattle rectal temperature

Directory of Open Access Journals (Sweden)

Tridib Debnath

2017-09-01

Full Text Available Aim: Dairy cattle health monitoring program becomes vital for detecting the febrile conditions to prevent the outbreak of the animal diseases as well as ensuring the fitness of the animals that are directly affecting the health of the consumers. The aim of this study was to validate real-time rectal temperature (RT data of radio frequency based digital (RFD thermometer with RT data of mercury bulb (MB thermometer in dairy cattle. Materials and Methods: Two experiments were conducted. In experiment I, six female Jersey crossbred cattle with a mean (±standard error of the mean body weight of 534.83±13.90 kg at the age of 12±0.52 years were used to record RT for 2 h on empty stomach and 2 h after feeding at 0, 30, 60, 90, and 120 min using a RFD thermometer as well as a MB thermometer. In experiment II, six female Jersey crossbred cattle were further used to record RT for 2 h before exercise and 2 h after exercise at 0, 30, 60, 90, and 120 min. Two-way repeated measures analysis of variance with post hoc comparisons by Bonferroni test was done. Results: Real-time RT data recorded by RFD thermometer as well as MB thermometer did not differ (p>0.05 before and after feeding/exercise. An increase (p<0.05 in RT after feeding/exercise in experimental crossbred cattle was recorded by both RFD thermometer and MB thermometer. Conclusion: The results obtained in the present study suggest that the body temperature recordings from RFD thermometer would be acceptable and thus RFD thermometer could work well for monitoring real-time RT in cattle.

Enhanced diffusion with abnormal temperature dependence in underdamped space-periodic systems subject to time-periodic driving

Science.gov (United States)

Marchenko, I. G.; Marchenko, I. I.; Zhiglo, A. V.

2018-01-01

We present a study of the diffusion enhancement of underdamped Brownian particles in a one-dimensional symmetric space-periodic potential due to external symmetric time-periodic driving with zero mean. We show that the diffusivity can be enhanced by many orders of magnitude at an appropriate choice of the driving amplitude and frequency. The diffusivity demonstrates abnormal (decreasing) temperature dependence at the driving amplitudes exceeding a certain value. At any fixed driving frequency Ω normal temperature dependence of the diffusivity is restored at low enough temperatures, T oscillation frequency at the potential minimum, the diffusivity is shown to decrease with Ω according to a power law, with the exponent related to the transient superdiffusion exponent. This behavior is found similar for the cases of sinusoidal in time and piecewise constant periodic ("square") driving.

Combined electrochemical, heat generation, and thermal model for large prismatic lithium-ion batteries in real-time applications

Science.gov (United States)

Farag, Mohammed; Sweity, Haitham; Fleckenstein, Matthias; Habibi, Saeid

2017-08-01

Real-time prediction of the battery's core temperature and terminal voltage is very crucial for an accurate battery management system. In this paper, a combined electrochemical, heat generation, and thermal model is developed for large prismatic cells. The proposed model consists of three sub-models, an electrochemical model, heat generation model, and thermal model which are coupled together in an iterative fashion through physicochemical temperature dependent parameters. The proposed parameterization cycles identify the sub-models' parameters separately by exciting the battery under isothermal and non-isothermal operating conditions. The proposed combined model structure shows accurate terminal voltage and core temperature prediction at various operating conditions while maintaining a simple mathematical structure, making it ideal for real-time BMS applications. Finally, the model is validated against both isothermal and non-isothermal drive cycles, covering a broad range of C-rates, and temperature ranges [-25 °C to 45 °C].

Time-dependent Dyson orbital theory

NARCIS (Netherlands)

Gritsenko, O.V.; Baerends, E.J.

2016-01-01

Although time-dependent density functional theory (TDDFT) has become the tool of choice for real-time propagation of the electron density ρN(t) of N-electron systems, it also encounters problems in this application. The first problem is the neglect of memory effects stemming from the, in TDDFT

A real-time Global Warming Index.

Science.gov (United States)

Haustein, K; Allen, M R; Forster, P M; Otto, F E L; Mitchell, D M; Matthews, H D; Frame, D J

2017-11-13

We propose a simple real-time index of global human-induced warming and assess its robustness to uncertainties in climate forcing and short-term climate fluctuations. This index provides improved scientific context for temperature stabilisation targets and has the potential to decrease the volatility of climate policy. We quantify uncertainties arising from temperature observations, climate radiative forcings, internal variability and the model response. Our index and the associated rate of human-induced warming is compatible with a range of other more sophisticated methods to estimate the human contribution to observed global temperature change.

Dynamic Reconfiguration in Real-Time Systems Energy, Performance, and Thermal Perspectives

CERN Document Server

Wang, Weixun; Ranka, Sanjay

2013-01-01

Given the widespread use of real-time multitasking systems, there are tremendous optimization opportunities if reconfigurable computing can be effectively incorporated while maintaining performance and other design constraints of typical applications. The focus of this book is to describe the dynamic reconfiguration techniques that can be safely used in real-time systems. This book provides comprehensive approaches by considering synergistic effects of computation, communication as well as storage together to significantly improve overall performance, power, energy and temperature.  Provides a comprehensive introduction to optimization and dynamic reconfiguration techniques in real-time embedded systems; Covers state-of-the-art techniques and ongoing research in reconfigurable architectures; Focuses on algorithms tuned for dynamic reconfiguration techniques in real-time systems;  Provides reference for anyone designing low-power systems, energy-/temperature-constrained devices, and power-performance efficie...

Real-time monitoring of radiofrequency ablation of liver tumors using thermal-dose calculation by MR temperature imaging: initial results in nine patients, including follow-up

International Nuclear Information System (INIS)

Lepetit-Coiffe, Matthieu; Quesson, Bruno; Moonen, Chrit T.W.; Laumonier, Herve; Trillaud, Herve; Seror, Olivier; Sesay, Musa-Bahazid; Grenier, Nicolas

2010-01-01

To assess the practical feasibility and effectiveness of real-time magnetic resonance (MR) temperature monitoring for the radiofrequency (RF) ablation of liver tumours in a clinical setting, nine patients (aged 49-87 years, five men and four women) with one malignant tumour (14-50 mm, eight hepatocellular carcinomas and one colorectal metastasis), were treated by 12-min RF ablation using a 1.5-T closed magnet for real-time temperature monitoring. The clinical monopolar RF device was filtered at 64 MHz to avoid electromagnetic interference. Real-time computation of thermal-dose (TD) maps, based on Sapareto and Dewey's equation, was studied to determine its ability to provide a clear end-point of the RF procedure. Absence of local recurrence on follow-up MR images obtained 45 days after the RF ablation was used to assess the apoptotic and necrotic prediction obtained by real-time TD maps. Seven out of nine tumours were completely ablated according to the real-time TD maps. Compared with 45-day follow-up MR images, TD maps accurately predicted two primary treatment failures, but were not relevant in the later progression of one case of secondary local tumour. The real-time TD concept is a feasible and promising monitoring method for the RF ablation of liver tumours. (orig.)

Real-time monitoring of radiofrequency ablation of liver tumors using thermal-dose calculation by MR temperature imaging: initial results in nine patients, including follow-up

Energy Technology Data Exchange (ETDEWEB)

Lepetit-Coiffe, Matthieu; Quesson, Bruno; Moonen, Chrit T.W. [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Laumonier, Herve; Trillaud, Herve [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Service de Radiologie, Hopital Saint-Andre, CHU Bordeaux, Bordeaux (France); Seror, Olivier [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Service de Radiologie, Hopital Jean Verdier, Bondy (France); Sesay, Musa-Bahazid [Service d' Anesthesie Reanimation III, Hopital Pellegrin, CHU Bordeaux, Bordeaux (France); Grenier, Nicolas [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Service d' Imagerie Diagnostique et Therapeutique de l' Adulte, Hopital Pellegrin, CHU Bordeaux, Bordeaux (France)

2010-01-15

To assess the practical feasibility and effectiveness of real-time magnetic resonance (MR) temperature monitoring for the radiofrequency (RF) ablation of liver tumours in a clinical setting, nine patients (aged 49-87 years, five men and four women) with one malignant tumour (14-50 mm, eight hepatocellular carcinomas and one colorectal metastasis), were treated by 12-min RF ablation using a 1.5-T closed magnet for real-time temperature monitoring. The clinical monopolar RF device was filtered at 64 MHz to avoid electromagnetic interference. Real-time computation of thermal-dose (TD) maps, based on Sapareto and Dewey's equation, was studied to determine its ability to provide a clear end-point of the RF procedure. Absence of local recurrence on follow-up MR images obtained 45 days after the RF ablation was used to assess the apoptotic and necrotic prediction obtained by real-time TD maps. Seven out of nine tumours were completely ablated according to the real-time TD maps. Compared with 45-day follow-up MR images, TD maps accurately predicted two primary treatment failures, but were not relevant in the later progression of one case of secondary local tumour. The real-time TD concept is a feasible and promising monitoring method for the RF ablation of liver tumours. (orig.)

Time-Dependent Behavior of Shrinkage Strain for Early Age Concrete Affected by Temperature Variation

OpenAIRE

Qin, Yu; Yi, Zhijian; Wang, Weina; Wang, Di

2017-01-01

Shrinkage has been proven to be an important property of early age concrete. The shrinkage strain leads to inherent engineering problems, such as cracking and loss of prestress. Atmospheric temperature is an important factor in shrinkage strain. However, current research does not provide much attention to the effect of atmospheric temperature on shrinkage of early age concrete. In this paper, a laboratory study was undertaken to present the time-dependent shrinkage of early age concrete under...

Processing grounded-wire TEM signal in time-frequency-pseudo-seismic domain: A new paradigm

Science.gov (United States)

Khan, M. Y.; Xue, G. Q.; Chen, W.; Huasen, Z.

2017-12-01

Grounded-wire TEM has received great attention in mineral, hydrocarbon and hydrogeological investigations for the last several years. Conventionally, TEM soundings have been presented as apparent resistivity curves as function of time. With development of sophisticated computational algorithms, it became possible to extract more realistic geoelectric information by applying inversion programs to 1-D & 3-D problems. Here, we analyze grounded-wire TEM data by carrying out analysis in time, frequency and pseudo-seismic domain supported by borehole information. At first, H, K, A & Q type geoelectric models are processed using a proven inversion program (1-D Occam inversion). Second, time-to-frequency transformation is conducted from TEM ρa(t) curves to magneto telluric MT ρa(f) curves for the same models based on all-time apparent resistivity curves. Third, 1-D Bostick's algorithm was applied to the transformed resistivity. Finally, EM diffusion field is transformed into propagating wave field obeying the standard wave equation using wavelet transformation technique and constructed pseudo-seismic section. The transformed seismic-like wave indicates that some reflection and refraction phenomena appear when the EM wave field interacts with geoelectric interface at different depth intervals due to contrast in resistivity. The resolution of the transformed TEM data is significantly improved in comparison to apparent resistivity plots. A case study illustrates the successful hydrogeophysical application of proposed approach in recovering water-filled mined-out area in a coal field located in Ye county, Henan province, China. The results support the introduction of pseudo-seismic imaging technology in short-offset version of TEM which can also be an useful aid if integrated with seismic reflection technique to explore possibilities for high resolution EM imaging in future.

Temperature dependence of ac response in diluted half-metallic CrO{sub 2} powder compact

Energy Technology Data Exchange (ETDEWEB)

Chen Yajie; Zhang Xiaoyu; Cai Tianyi; Li Zhenya

2004-10-06

We present a study on temperature dependence of impedance spectra of the cold-pressed chromium dioxide (CrO{sub 2})-titanic dioxide (TiO{sub 2}) composite over the temperature range of 77-300 K, and over the frequency range of 40 Hz-500 kHz. The microstructure of the sample is analyzed using transmission electron microscopy (TEM), SEM and X-ray diffraction (XRD). The impedance spectra exhibit a strong dependence upon temperature. By evaluating the ac electricity behavior of the composite, we find the experimental data are successfully described by a power-law behavior {sigma}{sub ac}=A(T){omega}{sup s}, in which the frequency exponent s shows slightly greater than a universal value (0{<=}s{<=}1), and rises approximately linearly with temperature over a broad range of low temperature.

Coherent quantum transport in disordered systems: II. Temperature dependence of carrier diffusion coefficients from the time-dependent wavepacket diffusion method

International Nuclear Information System (INIS)

Zhong, Xinxin; Zhao, Yi; Cao, Jianshu

2014-01-01

The time-dependent wavepacket diffusion method for carrier quantum dynamics (Zhong and Zhao 2013 J. Chem. Phys. 138 014111), a truncated version of the stochastic Schrödinger equation/wavefunction approach that approximately satisfies the detailed balance principle and scales well with the size of the system, is applied to investigate the carrier transport in one-dimensional systems including both the static and dynamic disorders on site energies. The predicted diffusion coefficients with respect to temperature successfully bridge from band-like to hopping-type transport. As demonstrated in paper I (Moix et al 2013 New J. Phys. 15 085010), the static disorder tends to localize the carrier, whereas the dynamic disorder induces carrier dynamics. For the weak dynamic disorder, the diffusion coefficients are temperature-independent (band-like property) at low temperatures, which is consistent with the prediction from the Redfield equation, and a linear dependence of the coefficient on temperature (hopping-type property) only appears at high temperatures. In the intermediate regime of dynamic disorder, the transition from band-like to hopping-type transport can be easily observed at relatively low temperatures as the static disorder increases. When the dynamic disorder becomes strong, the carrier motion can follow the hopping-type mechanism even without static disorder. Furthermore, it is found that the memory time of dynamic disorder is an important factor in controlling the transition from the band-like to hopping-type motions. (paper)

Real-Time Imaging System for the OpenPET

Science.gov (United States)

Tashima, Hideaki; Yoshida, Eiji; Kinouchi, Shoko; Nishikido, Fumihiko; Inadama, Naoko; Murayama, Hideo; Suga, Mikio; Haneishi, Hideaki; Yamaya, Taiga

2012-02-01

The OpenPET and its real-time imaging capability have great potential for real-time tumor tracking in medical procedures such as biopsy and radiation therapy. For the real-time imaging system, we intend to use the one-pass list-mode dynamic row-action maximum likelihood algorithm (DRAMA) and implement it using general-purpose computing on graphics processing units (GPGPU) techniques. However, it is difficult to make consistent reconstructions in real-time because the amount of list-mode data acquired in PET scans may be large depending on the level of radioactivity, and the reconstruction speed depends on the amount of the list-mode data. In this study, we developed a system to control the data used in the reconstruction step while retaining quantitative performance. In the proposed system, the data transfer control system limits the event counts to be used in the reconstruction step according to the reconstruction speed, and the reconstructed images are properly intensified by using the ratio of the used counts to the total counts. We implemented the system on a small OpenPET prototype system and evaluated the performance in terms of the real-time tracking ability by displaying reconstructed images in which the intensity was compensated. The intensity of the displayed images correlated properly with the original count rate and a frame rate of 2 frames per second was achieved with average delay time of 2.1 s.

Accelerator-tem interface facility and application

International Nuclear Information System (INIS)

Li Ming; He Jun; Yang Zheng; Zhou Lin; Liu Chuansheng; Guo Liping; Jiang Changzhong; Yang Shibo; Fu Dejun; Fan Xiangjun; Liu Jiarui; Lee, J.C.

2010-01-01

An accelerator-TEM interface facility has been established at Wuhan University. The system consists of an H800 TEM linked to a 200 kV ion implanter and a 2 x 1.7 MV tandetron accelerator. Measures were taken to isolate the TEM from mechanical vibration transmitted from the ion beam lines and good resolution was maintained with the TEM machine when operated under high zoom modes during the ion implantation. Nitrogen ions at 115 keV were successfully transported from the implanter into the TEM chamber through the interface system, and the ion currents measured at the entrance of the TEM column were between 20 and 180 nA. Structural evolution caused by ion irradiation in Si, GaAs, nanocrystal Ag were observed in situ. The TEM sample could be tilted by 52 degree and for low energy ion irradiation, real time observation was realized. The in situ observation showed that the critical implant dose for amorphization of Si is 2 x 10 14 cm -2 and it became fully amorphized at 3 x 10 15 cm -2 . Amorphization of GaAs started at 1 x 10 14 cm -2 , whereas for nanocrystal Ag, the starting dose was 6 x 10 14 cm -2 . The nuclear material C276 samples implanted with 115 keV Ar+ was also studied and dislocation loops with sizes of 3-12 nm were clearly observed after implantation to doses higher than 1 x 10 15 cm -2 . The density of the loops increased with the increase in the implant dose and evolution to polycrystalline and amorphous structures were observed at 5 x 10 15 cm -2 and 3 x 10 16 cm -2 , respectively. An in situ RBS/C chamber has been installed on the transport line of the accelerator-TEM interface system. This makes it possible to in situ measure composition and location of impurities in the lattice of the implanted samples. In addition, a 50 kV low-energy gaseous ion generator was installed close to the TEM chamber, which facilitates in situ TEM observation of helium bubbles formed in materials by helium implantation. (authors)

High-resolution near real-time drought monitoring in South Asia

OpenAIRE

Aadhar, Saran; Mishra, Vimal

2017-01-01

Drought in South Asia affect food and water security and pose challenges for millions of people. For policy-making, planning, and management of water resources at sub-basin or administrative levels, high-resolution datasets of precipitation and air temperature are required in near-real time. We develop a high-resolution (0.05°) bias-corrected precipitation and temperature data that can be used to monitor near real-time drought conditions over South Asia. Moreover, the dataset can be used to m...

Vessel thermal map real-time system for the JET tokamak

Directory of Open Access Journals (Sweden)

D. Alves

2012-05-01

Full Text Available The installation of international thermonuclear experimental reactor-relevant materials for the plasma facing components (PFCs in the Joint European Torus (JET is expected to have a strong impact on the operation and protection of the experiment. In particular, the use of all-beryllium tiles, which deteriorate at a substantially lower temperature than the formerly installed carbon fiber composite tiles, imposes strict thermal restrictions on the PFCs during operation. Prompt and precise responses are therefore required whenever anomalous temperatures are detected. The new vessel thermal map real-time application collects the temperature measurements provided by dedicated pyrometers and infrared cameras, groups them according to spatial location and probable offending heat source, and raises alarms that will trigger appropriate protective responses. In the context of the JET global scheme for the protection of the new wall, the system is required to run on a 10 ms cycle communicating with other systems through the real-time data network. In order to meet these requirements a commercial off-the-shelf solution has been adopted based on standard x86 multicore technology. Linux and the multithreaded application real-time executor (MARTe software framework were respectively the operating system of choice and the real-time framework used to build the application. This paper presents an overview of the system with particular technical focus on the configuration of its real-time capability and the benefits of the modular development approach and advanced tools provided by the MARTe framework.

Equilibrium finite-frequency noise of an interacting mesoscopic capacitor studied in time-dependent density functional theory

Science.gov (United States)

Dittmann, Niklas; Splettstoesser, Janine; Helbig, Nicole

2018-03-01

We calculate the frequency-dependent equilibrium noise of a mesoscopic capacitor in time-dependent density functional theory (TDDFT). The capacitor is modeled as a single-level quantum dot with on-site Coulomb interaction and tunnel coupling to a nearby reservoir. The noise spectra are derived from linear-response conductances via the fluctuation-dissipation theorem. Thereby, we analyze the performance of a recently derived exchange-correlation potential with time-nonlocal density dependence in the finite-frequency linear-response regime. We compare our TDDFT noise spectra with real-time perturbation theory and find excellent agreement for noise frequencies below the reservoir temperature.

RIMS (real-time imprint monitoring by scattering of light) study of pressure, temperature and resist effects on nanoimprint lithography

International Nuclear Information System (INIS)

Yu Zhaoning; Gao He; Chou, Stephen Y

2007-01-01

To optimize nanoimprint lithography (NIL), it is essential to be able to characterize and control the NIL process in situ and in real time. Recently we have developed a real-time imprint monitoring by the scattering-of-light (RIMS) approach, which allows us to detect the degree of resist deformation and the duration of resist penetration by a mould during the imprint process in real time. In this paper we report the performances of RIMS under a broad range of working conditions. RIMS data shows that the resist penetration is facilitated by increasing processing temperature, pressure and the resist film thickness; a prolonged pre-NIL resist baking step, on the other hand, has the effect of slowing it down. Our results provide further demonstration of the effectiveness of this method under different working conditions. RIMS measurements show not only how long an imprint takes to complete, but also how an imprint progresses with time and how it is affected by differences in processing parameters. These measurements provide information crucial for a better understanding and process optimization in NIL

Design-time performance analysis of component-based real-time systems

NARCIS (Netherlands)

Bondarev, E.

2009-01-01

In current real-time systems, performance metrics are one of the most challenging properties to specify, predict and measure. Performance properties depend on various factors, like environmental context, load profile, middleware, operating system, hardware platform and sharing of internal resources.

Vehicle routing with stochastic time-dependent travel times

NARCIS (Netherlands)

Lecluyse, C.; Woensel, van T.; Peremans, H.

2009-01-01

Assigning and scheduling vehicle routes in a stochastic time-dependent environment is a crucial management problem. The assumption that in a real-life environment everything goes according to an a priori determined static schedule is unrealistic. Our methodology builds on earlier work in which the

Vehicle routing with stochastic time-dependent travel times

NARCIS (Netherlands)

Lecluyse, C.; Woensel, van T.; Peremans, H.

2007-01-01

Assigning and scheduling vehicle routes in a stochastic time-dependent environment is a crucial management problem. The assumption that in a real-life environment everything goes according to an a priori determined static schedule is unrealistic. Our methodology builds on earlier work in which the

Concept Paper for Real-Time Temperature and Water QualityManagement for San Joaquin River Riparian Habitat Restoration

Energy Technology Data Exchange (ETDEWEB)

Quinn, Nigel W.T.

2004-12-20

The San Joaquin River Riparian Habitat Restoration Program (SJRRP) has recognized the potential importance of real-time monitoring and management to the success of the San Joaquin River (SJR) restoration endeavor. The first step to realizing making real-time management a reality on the middle San Joaquin River between Friant Dam and the Merced River will be the installation and operation of a network of permanent telemetered gauging stations that will allow optimization of reservoir releases made specifically for fish water temperature management. Given the limited reservoir storage volume available to the SJJRP, this functionality will allow the development of an adaptive management program, similar in concept to the VAMP though with different objectives. The virtue of this approach is that as management of the middle SJR becomes more routine, additional sensors can be added to the sensor network, initially deployed, to continue to improve conditions for anadromous fish.

Real-time simulation of thermal stresses and creep in plates subjected to transient heat input

DEFF Research Database (Denmark)

Hattel, Jesper Henri; Jacobsen, Torben Krogsdal; Hansen, P.N.

1997-01-01

-difference approach. It applies a general formulation which takes into account nonconstant material properties (e.g. temperature, material, or time dependency), heat-transfer coefficients, and creep. The temperature calculation applies a one-dimensional numerical model, whereas the stress analysis is semi......This paper presents a novel numerical technique for solving the temperature and stress fields in a plate subjected to arbitrarily varying transient boundary conditions (transient temperature and heat-flux variations) on a surface. The numerical method is based on the control-volume finite......-two-dimensional. Both plane stress and plane strain conditions are considered as extreme cases. It is shown that, by using the developed numerical technique, very fast real-time simulations can be performed. The method has proved its applicability in e.g. high-pressure die-casting, and applications to this industrial...

Inverse heat transfer analysis of a functionally graded fin to estimate time-dependent base heat flux and temperature distributions

International Nuclear Information System (INIS)

Lee, Haw-Long; Chang, Win-Jin; Chen, Wen-Lih; Yang, Yu-Ching

2012-01-01

Highlights: ► Time-dependent base heat flux of a functionally graded fin is inversely estimated. ► An inverse algorithm based on the conjugate gradient method and the discrepancy principle is applied. ► The distributions of temperature in the fin are determined as well. ► The influence of measurement error and measurement location upon the precision of the estimated results is also investigated. - Abstract: In this study, an inverse algorithm based on the conjugate gradient method and the discrepancy principle is applied to estimate the unknown time-dependent base heat flux of a functionally graded fin from the knowledge of temperature measurements taken within the fin. Subsequently, the distributions of temperature in the fin can be determined as well. It is assumed that no prior information is available on the functional form of the unknown base heat flux; hence the procedure is classified as the function estimation in inverse calculation. The temperature data obtained from the direct problem are used to simulate the temperature measurements. The influence of measurement errors and measurement location upon the precision of the estimated results is also investigated. Results show that an excellent estimation on the time-dependent base heat flux and temperature distributions can be obtained for the test case considered in this study.

A knowledge-based system framework for real-time monitoring applications

International Nuclear Information System (INIS)

Heaberlin, J.O.; Robinson, A.H.

1989-01-01

A real-time environment presents a challenge for knowledge-based systems for process monitoring with on-line data acquisition in nuclear power plants. These applications are typically data intensive. This, coupled with the dynamic nature of events on which problematic decisions are based, requires the development of techniques fundamentally different from those generally employed. Traditional approaches involve knowledge management techniques developed for static data, the majority of which is elicited directly from the user in a consultation environment. Inference mechanisms are generally noninterruptible, requiring all appropriate rules to be fired before new data can be accommodated. As a result, traditional knowledge-based applications in real-time environments have inherent problems in dealing with the time dependence of both the data and the solution process. For example, potential problems include obtaining a correct solution too late to be of use or focusing computing resources on problems that no longer exist. A knowledge-based system framework, the real-time framework (RTF), has been developed that can accommodate the time dependencies and resource trade-offs required for real-time process monitoring applications. This framework provides real-time functionality by using generalized problem-solving goals and control strategies that are modifiable during system operation and capable of accommodating feedback for redirection of activities

Time, stress, and temperature-dependent deformation in nanostructured copper: Stress relaxation tests and simulations

International Nuclear Information System (INIS)

Yang, Xu-Sheng; Wang, Yun-Jiang; Wang, Guo-Yong; Zhai, Hui-Ru; Dai, L.H.; Zhang, Tong-Yi

2016-01-01

In the present work, stress relaxation tests, high-resolution transmission electron microscopy (HRTEM), and molecular dynamics (MD) simulations were conducted on coarse-grained (cg), nanograined (ng), and nanotwinned (nt) copper at temperatures of 22 °C (RT), 30 °C, 40 °C, 50 °C, and 75 °C. The comprehensive investigations provide sufficient information for the building-up of a formula to describe the time, stress, and temperature-dependent deformation and clarify the relationship among the strain rate sensitivity parameter, stress exponent, and activation volume. The typically experimental curves of logarithmic plastic strain rate versus stress exhibited a three staged relaxation process from a linear high stress relaxation region to a subsequent nonlinear stress relaxation region and finally to a linear low stress relaxation region, which only showed-up at the test temperatures higher than 22 °C, 22 °C, and 30 °C, respectively, in the tested cg-, ng-, and nt-Cu specimens. The values of stress exponent, stress-independent activation energy, and activation volume were determined from the experimental data in the two linear regions. The determined activation parameters, HRTEM images, and MD simulations consistently suggest that dislocation-mediated plastic deformation is predominant in all tested cg-, ng-, and nt-Cu specimens in the initial linear high stress relaxation region at the five relaxation temperatures, whereas in the linear low stress relaxation region, the grain boundary (GB) diffusion-associated deformation is dominant in the ng- and cg-Cu specimens, while twin boundary (TB) migration, i.e., twinning and detwinning with parallel partial dislocations, governs the time, stress, and temperature-dependent deformation in the nt-Cu specimens.

Temperature dependence of the coherence in polariton condensates

Science.gov (United States)

Rozas, E.; Martín, M. D.; Tejedor, C.; Viña, L.; Deligeorgis, G.; Hatzopoulos, Z.; Savvidis, P. G.

2018-02-01

We present a time-resolved experimental study of the temperature effect on the coherence of traveling polariton condensates. The simultaneous detection of their emission both in real and reciprocal space allows us to fully monitor the condensates' dynamics. We obtain fringes in reciprocal space as a result of the interference between polariton wave packets (WPs) traveling with the same speed. The periodicity of these fringes is inversely proportional to the spatial distance between the interfering WPs. In a similar fashion, we obtain interference fringes in real space when WPs traveling in opposite directions meet. The visibility of both real- and reciprocal-space interference fringes rapidly decreases with increasing temperature and vanishes. A theoretical description of the phase transition, considering the coexistence of condensed and noncondensed particles, for an out-of-equilibrium condensate such as ours is still missing, yet a comparison with theories developed for atomic condensates allows us to infer a critical temperature for the BEC-like transition when the visibility goes to zero.

Predicting Near Real-Time Inundation Occurrence from Complimentary Satellite Microwave Brightness Temperature Observations

Science.gov (United States)

Fisher, C. K.; Pan, M.; Wood, E. F.

2017-12-01

Throughout the world, there is an increasing need for new methods and data that can aid decision makers, emergency responders and scientists in the monitoring of flood events as they happen. In many regions, it is possible to examine the extent of historical and real-time inundation occurrence from visible and infrared imagery provided by sensors such as MODIS or the Landsat TM; however, this is not possible in regions that are densely vegetated or are under persistent cloud cover. In addition, there is often a temporal mismatch between the sampling of a particular sensor and a given flood event, leading to limited observations in near real-time. As a result, there is a need for alternative methods that take full advantage of complimentary remotely sensed data sources, such as available microwave brightness temperature observations (e.g., SMAP, SMOS, AMSR2, AMSR-E, and GMI), to aid in the estimation of global flooding. The objective of this work was to develop a high-resolution mapping of inundated areas derived from multiple satellite microwave sensor observations with a daily temporal resolution. This system consists of first retrieving water fractions from complimentary microwave sensors (AMSR-2 and SMAP) which may spatially and temporally overlap in the region of interest. Using additional information in a Random Forest classifier, including high resolution topography and multiple datasets of inundated area (both historical and empirical), the resulting retrievals are spatially downscaled to derive estimates of the extent of inundation at a scale relevant to management and flood response activities ( 90m or better) instead of the relatively coarse resolution water fractions, which are limited by the microwave sensor footprints ( 5-50km). Here we present the training and validation of this method for the 2015 floods that occurred in Houston, Texas. Comparing the predicted inundation against historical occurrence maps derived from the Landsat TM record and MODIS

Real time polymer nanocomposites-based physical nanosensors: theory and modeling

Science.gov (United States)

Bellucci, Stefano; Shunin, Yuri; Gopeyenko, Victor; Lobanova-Shunina, Tamara; Burlutskaya, Nataly; Zhukovskii, Yuri

2017-09-01

Functionalized carbon nanotubes and graphene nanoribbons nanostructures, serving as the basis for the creation of physical pressure and temperature nanosensors, are considered as tools for ecological monitoring and medical applications. Fragments of nanocarbon inclusions with different morphologies, presenting a disordered system, are regarded as models for nanocomposite materials based on carbon nanoсluster suspension in dielectric polymer environments (e.g., epoxy resins). We have formulated the approach of conductivity calculations for carbon-based polymer nanocomposites using the effective media cluster approach, disordered systems theory and conductivity mechanisms analysis, and obtained the calibration dependences. Providing a proper description of electric responses in nanosensoring systems, we demonstrate the implementation of advanced simulation models suitable for real time control nanosystems. We also consider the prospects and prototypes of the proposed physical nanosensor models providing the comparisons with experimental calibration dependences.

Real-Time Pore Pressure Detection: Indicators and Improved Methods

Directory of Open Access Journals (Sweden)

Jincai Zhang

2017-01-01

Full Text Available High uncertainties may exist in the predrill pore pressure prediction in new prospects and deepwater subsalt wells; therefore, real-time pore pressure detection is highly needed to reduce drilling risks. The methods for pore pressure detection (the resistivity, sonic, and corrected d-exponent methods are improved using the depth-dependent normal compaction equations to adapt to the requirements of the real-time monitoring. A new method is proposed to calculate pore pressure from the connection gas or elevated background gas, which can be used for real-time pore pressure detection. The pore pressure detection using the logging-while-drilling, measurement-while-drilling, and mud logging data is also implemented and evaluated. Abnormal pore pressure indicators from the well logs, mud logs, and wellbore instability events are identified and analyzed to interpret abnormal pore pressures for guiding real-time drilling decisions. The principles for identifying abnormal pressure indicators are proposed to improve real-time pore pressure monitoring.

Real time animation of space plasma phenomena

International Nuclear Information System (INIS)

Jordan, K.F.; Greenstadt, E.W.

1987-01-01

In pursuit of real time animation of computer simulated space plasma phenomena, the code was rewritten for the Massively Parallel Processor (MPP). The program creates a dynamic representation of the global bowshock which is based on actual spacecraft data and designed for three dimensional graphic output. This output consists of time slice sequences which make up the frames of the animation. With the MPP, 16384, 512 or 4 frames can be calculated simultaneously depending upon which characteristic is being computed. The run time was greatly reduced which promotes the rapid sequence of images and makes real time animation a foreseeable goal. The addition of more complex phenomenology in the constructed computer images is now possible and work proceeds to generate these images

Effects of computing time delay on real-time control systems

Science.gov (United States)

Shin, Kang G.; Cui, Xianzhong

1988-01-01

The reliability of a real-time digital control system depends not only on the reliability of the hardware and software used, but also on the speed in executing control algorithms. The latter is due to the negative effects of computing time delay on control system performance. For a given sampling interval, the effects of computing time delay are classified into the delay problem and the loss problem. Analysis of these two problems is presented as a means of evaluating real-time control systems. As an example, both the self-tuning predicted (STP) control and Proportional-Integral-Derivative (PID) control are applied to the problem of tracking robot trajectories, and their respective effects of computing time delay on control performance are comparatively evaluated. For this example, the STP (PID) controller is shown to outperform the PID (STP) controller in coping with the delay (loss) problem.

Measuring temperature dependence of soil respiration: importance of incubation time, soil type, moisture content and model fits

Science.gov (United States)

Schipper, L. A.; Robinson, J.; O'Neill, T.; Ryburn, J.; Arcus, V. L.

2015-12-01

Developing robust models of the temperature response and sensitivity of soil respiration is critical for determining changes carbon cycling in response to climate change and at daily to annual time scales. Currently, approaches for measuring temperature dependence of soil respiration generally use long incubation times (days to weeks and months) at a limited number of incubation temperatures. Long incubation times likely allow thermal adaptation by the microbial population so that results are poorly representative of in situ soil responses. Additionally, too few incubation temperatures allows for the fit and justification of many different predictive equations, which can lead to inaccuracies when used for carbon budgeting purposes. We have developed a method to rapidly determine the response of soil respiration rate to wide range of temperatures. An aluminium block with 44 sample slots is heated at one end and cooled at the other to give a temperature gradient from 0 to 55°C at about one degree increments. Soil respiration is measured within 5 hours to minimise the possibility of thermal adaptation. We have used this method to demonstrate the similarity of temperature sensitivity of respiration for different soils from the same location across seasons. We are currently testing whether long-term (weeks to months) incubation alter temperature response and sensitivity that occurs in situ responses. This method is also well suited for determining the most appropriate models of temperature dependence and sensitivity of soil respiration (including macromolecular rate theory MMRT). With additional testing, this method is expected to be a more reliable method of measuring soil respiration rate for soil quality and modelling of soil carbon processes.

Diffusive real-time dynamics of a particle with Berry curvature

Science.gov (United States)

Misaki, Kou; Miyashita, Seiji; Nagaosa, Naoto

2018-02-01

We study theoretically the influence of Berry phase on the real-time dynamics of the single particle focusing on the diffusive dynamics, i.e., the time dependence of the distribution function. Our model can be applied to the real-time dynamics of intraband relaxation and diffusion of optically excited excitons, trions, or particle-hole pair. We found that the dynamics at the early stage is deeply influenced by the Berry curvature in real space (B ), momentum space (Ω ), and also the crossed space between these two (C ). For example, it is found that Ω induces the rotation of the wave packet and causes the time dependence of the mean square displacement of the particle to be linear in time t at the initial stage; it is qualitatively different from the t3 dependence in the absence of the Berry curvature. It is also found that Ω and C modify the characteristic time scale of the thermal equilibration of momentum distribution. Moreover, the dynamics under various combinations of B ,Ω , and C shows singular behaviors such as the critical slowing down or speeding up of the momentum equilibration and the reversals of the direction of rotations. The relevance of our model for time-resolved experiments in transition metal dichalcogenides is also discussed.

Real-time luminescence from Al2O3 fiber dosimeters

International Nuclear Information System (INIS)

Polf, J.C.; Yukihara, E.G.; Akselrod, M.S.; McKeever, S.W.S.

2004-01-01

The real-time luminescence signal from Al 2 O 3 single crystal fibers, monitored during simultaneous irradiation and optical stimulation, was investigated using computer simulations and experimental measurements. Both radioluminescence (RL) and optically stimulated luminescence (OSL) signals were studied. The simulations were performed initially using a simple one-trap/one-recombination-center energy band model, and then extended to include shallow and deep electron traps as well. Real-time luminescence experiments were performed for different radiation dose rates and optical stimulation powers using periodic laser stimulation of the samples through a fiber optic cable, and the experimental results were compared with the predictions from the computer simulations. The luminescence signal was observed, both theoretically and experimentally, to increase from its initial value to a steady-state level. The steady-state RL and OSL levels were found to be dependent on dose rate, the steady-state level of the real-time OSL being independent of laser power. It was also shown that the total integrated absorbed dose throughout the irradiation period can be determined by correcting the real-time OSL signal for depletion caused by each laser stimulation pulse. The effects of the shallow and deep traps on the time-dependence of the real-time luminescence signal were studied comparing the experimental data from several Al 2 O 3 fibers known to have different trapping state concentrations. The additional traps were found to slow the response of the real-time luminescence such that the time to reach steady state was increased as the additional traps were added

Mechanisms for ITB formation and control in Alcator C-Mod identified through gyrokinetic simulations of TEM turbulence

International Nuclear Information System (INIS)

Ernst, D.R.; Basse, N.; Bonoli, P.T.; Catto, P.J.; Fiore, C.L.; Greenwald, M.; Hubbard, A.E.; Marmar, E.S.; Porkolab, M.; Rice, J.E.; Zeller, K.; Zhurovich, K.; Dorland, W.

2005-01-01

Internal particle and thermal energy transport barriers are produced in Alcator C-Mod with off-axis ICRF heating, with core densities exceeding 10 21 m -3 , without core fueling, and with little change in the temperature profile. Applying on-axis ICRF heating controls the core density gradient and rate of rise. The present study employs linear and nonlinear gyrokinetic simulations of trapped electron mode (TEM) turbulence to explore mechanisms for ITB formation and control in Alcator C-Mod ITB experiments. Anomalous pinches are found to be negligible in our simulations; further, the collisional Ware pinch is sufficient to account for the slow density rise, lasting many energy confinement times. The simulations have revealed new nonlinear physics of TEM turbulence. The critical density gradient for onset of TEM turbulent transport is nonlinearly up-shifted by zonal flows. As the density profile peaks, during ITB formation, this nonlinear critical gradient is eventually exceeded, and the turbulent particle diffusivity from GS2 gyrokinetic simulations matches the particle diffusivity from transport analysis, within experimental errors. A stable equilibrium is then established when the TEM turbulent diffusion balances the Ware pinch in the ITB. This equilibrium is sensitive to temperature through gyroBohm scaling of the TEM turbulent transport, and the collisionality dependence of the neoclassical pinch, providing for control of the density rate of rise with on-axis RF heating. With no core particle fueling, and ∼1 mm between density spatial channels, the C-Mod experiments provide a nearly ideal test bed for particle transport studies. The pure TEM is the only unstable drift mode in the ITB, producing particle transport driven by the density gradient. (author)

Prospects of real-time ion temperature and rotation profiles based on neural-network charge exchange analysis

Energy Technology Data Exchange (ETDEWEB)

Koenig, R W.T.; Von Hellermann, M [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Svensson, J [Royal Inst. of Tech., Stockholm (Sweden)

1994-07-01

A back-propagation neural network technique is used at JET to extract plasma parameters like ion temperature, rotation velocities or spectral line intensities from charge exchange (CX) spectra. It is shown that in the case of the C VI CX spectra, neural networks can give a good estimation (better than +-20% accuracy) for the main plasma parameters (Ti, V{sub rot}). Since the neural network approach involves no iterations or initial guesses the speed with which a spectrum is processed is so high (0.2 ms/spectrum) that real time analysis will be achieved in the near future. 4 refs., 8 figs.

Prospects of real-time ion temperature and rotation profiles based on neural-network charge exchange analysis

International Nuclear Information System (INIS)

Koenig, R.W.T.; Von Hellermann, M.

1994-01-01

A back-propagation neural network technique is used at JET to extract plasma parameters like ion temperature, rotation velocities or spectral line intensities from charge exchange (CX) spectra. It is shown that in the case of the C VI CX spectra, neural networks can give a good estimation (better than +-20% accuracy) for the main plasma parameters (Ti, V rot ). Since the neural network approach involves no iterations or initial guesses the speed with which a spectrum is processed is so high (0.2 ms/spectrum) that real time analysis will be achieved in the near future. 4 refs., 8 figs

Real-time shadows

CERN Document Server

Eisemann, Elmar; Assarsson, Ulf; Wimmer, Michael

2011-01-01

Important elements of games, movies, and other computer-generated content, shadows are crucial for enhancing realism and providing important visual cues. In recent years, there have been notable improvements in visual quality and speed, making high-quality realistic real-time shadows a reachable goal. Real-Time Shadows is a comprehensive guide to the theory and practice of real-time shadow techniques. It covers a large variety of different effects, including hard, soft, volumetric, and semi-transparent shadows.The book explains the basics as well as many advanced aspects related to the domain

Real-world exhaust temperature profiles of on-road heavy-duty diesel vehicles equipped with selective catalytic reduction.

Science.gov (United States)

Boriboonsomsin, Kanok; Durbin, Thomas; Scora, George; Johnson, Kent; Sandez, Daniel; Vu, Alexander; Jiang, Yu; Burnette, Andrew; Yoon, Seungju; Collins, John; Dai, Zhen; Fulper, Carl; Kishan, Sandeep; Sabisch, Michael; Jackson, Doug

2018-09-01

On-road heavy-duty diesel vehicles are a major contributor of oxides of nitrogen (NO x ) emissions. In the US, many heavy-duty diesel vehicles employ selective catalytic reduction (SCR) technology to meet the 2010 emission standard for NO x . Typically, SCR needs to be at least 200°C before a significant level of NO x reduction is achieved. However, this SCR temperature requirement may not be met under some real-world operating conditions, such as during cold starts, long idling, or low speed/low engine load driving activities. The frequency of vehicle operation with low SCR temperature varies partly by the vehicle's vocational use. In this study, detailed vehicle and engine activity data were collected from 90 heavy-duty vehicles involved in a range of vocations, including line haul, drayage, construction, agricultural, food distribution, beverage distribution, refuse, public work, and utility repair. The data were used to create real-world SCR temperature and engine load profiles and identify the fraction of vehicle operating time that SCR may not be as effective for NO x control. It is found that the vehicles participated in this study operate with SCR temperature lower than 200°C for 11-70% of the time depending on their vocation type. This implies that real-world NO x control efficiency could deviate from the control efficiency observed during engine certification. Copyright © 2018 Elsevier B.V. All rights reserved.

Temperature-dependent μ-Raman investigation of struvite crystals.

Science.gov (United States)

Prywer, Jolanta; Kasprowicz, D; Runka, T

2016-04-05

The effect of temperature on the vibrational properties of struvite crystals grown from silica gels was systematically studied by μ-Raman spectroscopy. The time-dependent Raman spectra recorded in the process of long time annealing of struvite crystal at 353 K do not indicate structural changes in the struvite crystal with the time of annealing. The temperature-dependent Raman spectra recorded in the range 298-423 K reveal a phase transition in struvite at about 368 K. Above this characteristic temperature, some of bands assigned to vibrations of the PO4 and NH4 tetrahedra and water molecules observed in the Raman spectra in low temperatures (orthorhombic phase) change their spectral parameters or disappear, which indicates a transition to a higher symmetry structure of struvite in the range of high temperatures. Copyright © 2016 Elsevier B.V. All rights reserved.

Real-Time Monitoring of Neutron Capture Cross Section in the IPR-R1 TRIGA Research Reactor as a Fuel Temperature Function

Energy Technology Data Exchange (ETDEWEB)

Palma, D.A.P. [Comissao Nacional de Energia Nuclear, CNEN, General Severiano Street, 90, 22290-901, Rio de Janeiro (Brazil); Mesquita, A.Z.; Souza, R.M.G.P. [Comissao Nacional de Energia Nuclear, CNEN/CDTN, Av. Presidente Antonio Carlos, 6627, 31270-901, Belo Horizonte (Brazil); Martinez, A.S. [Programa de Engenharia Nuclear, COPPE/UFRJ, Av. Horacio Macedo, 2030, Bloco G, 21941- 914, Rio de Janeiro (Brazil)

2011-07-01

Nuclear reactor operators have to monitor the behaviour of different nuclear and design parameters that vary in time to ensure the operating safety of the reactor. In recent years several operating parameters for the IPR-R1 TRIGA research reactor were monitored and indicated in real-time by the data acquisition system developed for the reactor, with all the data being stored in a hard disk in the data acquisition computer, to build in this way a database. The goal of this work is to insert in the set of parameters already collected the neutron capture cross sections for the fuel, from the power and temperature numbers obtained in real-time. The experimental data was obtained by using a fuel element instrumented with temperature sensors, located in the core of the IPR-R1 TRIGA research reactor at the CDTN - Centre for Development of Nuclear. This information is useful for the continuous monitoring of the reaction rate in neutron capture. For that, a new analytical formulation is used for the Doppler broadening function proposed by Palma and Martinez which is free from special functions in its functional form and with easy computing implementation. The results obtained were satisfactory from the standpoint of accuracy in comparison with the numerical reference method and indicate that it is possible to carry out real-time monitoring of the neutron capture cross section in the fuel. (author)

LabVIEW Real-Time

CERN Multimedia

CERN. Geneva; Flockhart, Ronald Bruce; Seppey, P

2003-01-01

With LabVIEW Real-Time, you can choose from a variety of RT Series hardware. Add a real-time data acquisition component into a larger measurement and automation system or create a single stand-alone real-time solution with data acquisition, signal conditioning, motion control, RS-232, GPIB instrumentation, and Ethernet connectivity. With the various hardware options, you can create a system to meet your precise needs today, while the modularity of the system means you can add to the solution as your system requirements grow. If you are interested in Reliable and Deterministic systems for Measurement and Automation, you will profit from this seminar. Agenda: Real-Time Overview LabVIEW RT Hardware Platforms - Linux on PXI Programming with LabVIEW RT Real-Time Operating Systems concepts Timing Applications Data Transfer

Real-Time Performance of Hybrid Mobile Robot Control Utilizing USB Protocol

Directory of Open Access Journals (Sweden)

Jacek Augustyn

2015-02-01

Full Text Available This article discusses the problem of usability of the USB 2.0 protocol in the area of real-time control of a mobile robot. Optimization methods of data transfer handling were proposed. The impact of the optimization results on the entire system's performance was examined in practice. As a test-bed, a hybrid system composed of two devices communicating by direct USB connection was implemented. The first of the mentioned devices was a 32-bit SoC micro-system serving as a direct control unit, and the second one was an off-the-shelf PDA providing supervisory control and logging. Due to this design, the system meets regimes of the real-time constraints and maintains continuity of a data stream at a large bandwidth. The real-time performances of subsystems and the entire system were experimentally examined depending on various operating conditions. Thanks to the performed experiments, the dependency of real-time limits on operational parameters has been determined.

Real-time LMR control parameter generation using advanced adaptive synthesis

International Nuclear Information System (INIS)

King, R.W.; Mott, J.E.

1990-01-01

The reactor ''delta T'', the difference between the average core inlet and outlet temperatures, for the liquid-sodium-cooled Experimental Breeder Reactor 2 is empirically synthesized in real time from, a multitude of examples of past reactor operation. The real-time empirical synthesis is based on reactor operation. The real-time empirical synthesis is based on system state analysis (SSA) technology embodied in software on the EBR 2 data acquisition computer. Before the real-time system is put into operation, a selection of reactor plant measurements is made which is predictable over long periods encompassing plant shutdowns, core reconfigurations, core load changes, and plant startups. A serial data link to a personal computer containing SSA software allows the rapid verification of the predictability of these plant measurements via graphical means. After the selection is made, the real-time synthesis provides a fault-tolerant estimate of the reactor delta T accurate to +/-1%. 5 refs., 7 figs

A real time zero-dimensional diagnostic model for the calculation of in-cylinder temperatures, HRR and nitrogen oxides in diesel engines

International Nuclear Information System (INIS)

Finesso, Roberto; Spessa, Ezio

2014-01-01

Highlights: • Real-time zero-dimensional three-zone diagnostic combustion model. • Capable of evaluating in-cylinder temperatures, HRR and NOx in DI diesel engines. • Able to be integrated in the engine ECU for control applications. • Able to be integrated in the test bed acquisition software for calibration tasks. • Tested under both steady state and fast transient conditions. - Abstract: A real-time zero-dimensional diagnostic combustion model has been developed and assessed to evaluate in-cylinder temperatures, HRR (heat release rate) and NOx (nitrogen oxides) in DI (Direct Injection) diesel engines under steady state and transient conditions. The approach requires very little computational time, that is, of the order of a few milliseconds, and is therefore suitable for real-time applications. It could, for example, be implemented in an ECU (Engine Control Unit) for the on-board diagnostics of combustion and emission formation processes, or it could be integrated in acquisition software installed on an engine test bench for indicated analysis. The model could also be used for post-processing analysis of previously acquired experimental data. The methodology is based on a three-zone thermodynamic model: the combustion chamber is divided into a fuel zone, an unburned gas zone and a stoichiometric burned gas zone, to which the energy and mass conservation equations are applied. The main novelty of the proposed method is that the equations can be solved in closed form, thus making the approach suitable for real-time applications. The evaluation of the temperature of burned gases allows the in-cylinder NOx concentration to be calculated, on the basis of prompt and Zeldovich thermal mechanisms. The procedure also takes into account the NOx level in the intake charge, and is therefore suitable for engines equipped with traditional short-route EGR (Exhaust Gas Recirculation) systems, and engines equipped with SCR (Selective Catalytic Reduction) and long

Exploiting Microwave Imaging Methods for Real-Time Monitoring of Thermal Ablation

Directory of Open Access Journals (Sweden)

Rosa Scapaticci

2017-01-01

Full Text Available Microwave thermal ablation is a cancer treatment that exploits local heating caused by a microwave electromagnetic field to induce coagulative necrosis of tumor cells. Recently, such a technique has significantly progressed in the clinical practice. However, its effectiveness would dramatically improve if paired with a noninvasive system for the real-time monitoring of the evolving dimension and shape of the thermally ablated area. In this respect, microwave imaging can be a potential candidate to monitor the overall treatment evolution in a noninvasive way, as it takes direct advantage from the dependence of the electromagnetic properties of biological tissues from temperature. This paper explores such a possibility by presenting a proof of concept validation based on accurate simulated imaging experiments, run with respect to a scenario that mimics an ex vivo experimental setup. In particular, two model-based inversion algorithms are exploited to tackle the imaging task. These methods provide independent results in real-time and their integration improves the quality of the overall tracking of the variations occurring in the target and surrounding regions.

Concepts of real time and semi-real time material control

International Nuclear Information System (INIS)

Lovett, J.E.

1975-01-01

After a brief consideration of the traditional material balance accounting on an MBA basis, this paper explores the basic concepts of real time and semi-real time material control, together with some of the major problems to be solved. Three types of short-term material control are discussed: storage, batch processing, and continuous processing. (DLC)

Real Time Systems

DEFF Research Database (Denmark)

Christensen, Knud Smed

2000-01-01

Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems.......Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems....

Real Time Radiation Monitoring Using Nanotechnology

Science.gov (United States)

Li, Jing (Inventor); Hanratty, James J. (Inventor); Wilkins, Richard T. (Inventor); Lu, Yijiang (Inventor)

2016-01-01

System and method for monitoring receipt and estimating flux value, in real time, of incident radiation, using two or more nanostructures (NSs) and associated terminals to provide closed electrical paths and to measure one or more electrical property change values .DELTA.EPV, associated with irradiated NSs, during a sequence of irradiation time intervals. Effects of irradiation, without healing and with healing, of the NSs, are separately modeled for first order and second order healing. Change values.DELTA.EPV are related to flux, to cumulative dose received by NSs, and to radiation and healing effectivity parameters and/or.mu., associated with the NS material and to the flux. Flux and/or dose are estimated in real time, based on EPV change values, using measured .DELTA.EPV values. Threshold dose for specified changes of biological origin (usually undesired) can be estimated. Effects of time-dependent radiation flux are analyzed in pre-healing and healing regimes.

Real time expert systems

International Nuclear Information System (INIS)

Asami, Tohru; Hashimoto, Kazuo; Yamamoto, Seiichi

1992-01-01

Recently, aiming at the application to the plant control for nuclear reactors and traffic and communication control, the research and the practical use of the expert system suitable to real time processing have become conspicuous. In this report, the condition for the required function to control the object that dynamically changes within a limited time is presented, and the technical difference between the real time expert system developed so as to satisfy it and the expert system of conventional type is explained with the actual examples and from theoretical aspect. The expert system of conventional type has the technical base in the problem-solving equipment originating in STRIPS. The real time expert system is applied to the fields accompanied by surveillance and control, to which conventional expert system is hard to be applied. The requirement for the real time expert system, the example of the real time expert system, and as the techniques of realizing real time processing, the realization of interruption processing, dispersion processing, and the mechanism of maintaining the consistency of knowledge are explained. (K.I.)

Real-time optical diagnostics of graphene growth induced by pulsed chemical vapor deposition

Science.gov (United States)

Puretzky, Alexander A.; Geohegan, David B.; Pannala, Sreekanth; Rouleau, Christopher M.; Regmi, Murari; Thonnard, Norbert; Eres, Gyula

2013-06-01

The kinetics and mechanisms of graphene growth on Ni films at 720-880 °C have been measured using fast pulses of acetylene and real-time optical diagnostics. In situ UV-Raman spectroscopy was used to unambiguously detect isothermal graphene growth at high temperatures, measure the growth kinetics with ~1 s temporal resolution, and estimate the fractional precipitation upon cooldown. Optical reflectivity and videography provided much faster temporal resolution. Both the growth kinetics and the fractional isothermal precipitation were found to be governed by the C2H2 partial pressure in the CVD pulse for a given film thickness and temperature, with up to ~94% of graphene growth occurring isothermally within 1 second at 800 °C at high partial pressures. At lower partial pressures, isothermal graphene growth is shown to continue 10 seconds after the gas pulse. These flux-dependent growth kinetics are described in the context of a dissolution/precipitation model, where carbon rapidly dissolves into the Ni film and later precipitates driven by gradients in the chemical potential. The combination of pulsed-CVD and real-time optical diagnostics opens new opportunities to understand and control the fast, sub-second growth of graphene on various substrates at high temperatures.The kinetics and mechanisms of graphene growth on Ni films at 720-880 °C have been measured using fast pulses of acetylene and real-time optical diagnostics. In situ UV-Raman spectroscopy was used to unambiguously detect isothermal graphene growth at high temperatures, measure the growth kinetics with ~1 s temporal resolution, and estimate the fractional precipitation upon cooldown. Optical reflectivity and videography provided much faster temporal resolution. Both the growth kinetics and the fractional isothermal precipitation were found to be governed by the C2H2 partial pressure in the CVD pulse for a given film thickness and temperature, with up to ~94% of graphene growth occurring isothermally

The effects of temperature, organic matter and time-dependency on rheological properties of dry anaerobic digested swine manure.

Science.gov (United States)

Liu, Gang-Jin; Liu, Yi; Wang, Zhi-Yong; Lei, Yun-Hui; Chen, Zi-Ai; Deng, Liang-Wei

2015-04-01

An efficient way to avoid the pollution of swine wastewater is the application of dry anaerobic digestion, which needs rheological parameter for stirring and pipe designing. The rheological properties of this kind of sludge have been studied for many decades, yet their effects only solid concentration has been investigated widely. In this paper, the influences of temperature, organic and time-dependency on the efficiency of anaerobic digested swine manure were studied. The viscosity decreased with temperature arranged from 10 to 60 °C which caused increase in protein from 7.18 to 8.49 g/kg. 60 °C can make the digested swine manure with TS from 16.6% to 21.5% reach to the same rheology state. The added peptone decreased the viscosity because of its function of water-reducing admixture and air entraining mixture. Time-dependent experiment showed the decrease of shear stress over time. The first and the second yield stress of dry anaerobic digested swine manure were evaluated through time-dependent model. Copyright © 2015 Elsevier Ltd. All rights reserved.

In-situ TEM characterization of nanomaterials and devices

KAUST Repository

Kim, Moon; Park, Seongyong; Cha, Dong Kyu; Kim, Jiyoung; Floresca, Herman Carlo; Lu, Ning; Wang, Jinguo

2011-01-01

Electrical properties of nano size devices were directly measured by TEM. Real time observation of phase transition behavior in PRAM revealed that the volume of the crystalline phase is the main factor in determining cell resistance. In the transistor device, we have identified the doping type and area by measuring the I-V curve at the individual nano contact on the specimen. The evolution of the graphene edge structure was controlled and monitored at and up to 1200°C in-situ. © 2011 IEEE.

In-situ TEM characterization of nanomaterials and devices

KAUST Repository

Kim, Moon

2011-10-01

Electrical properties of nano size devices were directly measured by TEM. Real time observation of phase transition behavior in PRAM revealed that the volume of the crystalline phase is the main factor in determining cell resistance. In the transistor device, we have identified the doping type and area by measuring the I-V curve at the individual nano contact on the specimen. The evolution of the graphene edge structure was controlled and monitored at and up to 1200°C in-situ. © 2011 IEEE.

High-Resolution Near Real-Time Drought Monitoring in South Asia

Science.gov (United States)

Aadhar, S.; Mishra, V.

2017-12-01

Drought in South Asia affect food and water security and pose challenges for millions of people. For policy-making, planning and management of water resources at the sub-basin or administrative levels, high-resolution datasets of precipitation and air temperature are required in near-real time. Here we develop a high resolution (0.05 degree) bias-corrected precipitation and temperature data that can be used to monitor near real-time drought conditions over South Asia. Moreover, the dataset can be used to monitor climatic extremes (heat waves, cold waves, dry and wet anomalies) in South Asia. A distribution mapping method was applied to correct bias in precipitation and air temperature (maximum and minimum), which performed well compared to the other bias correction method based on linear scaling. Bias-corrected precipitation and temperature data were used to estimate Standardized precipitation index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI) to assess the historical and current drought conditions in South Asia. We evaluated drought severity and extent against the satellite-based Normalized Difference Vegetation Index (NDVI) anomalies and satellite-driven Drought Severity Index (DSI) at 0.05˚. We find that the bias-corrected high-resolution data can effectively capture observed drought conditions as shown by the satellite-based drought estimates. High resolution near real-time dataset can provide valuable information for decision-making at district and sub- basin levels.

Time-Dependent Hartree-Fock Approach to Nuclear Pasta at Finite Temperature

International Nuclear Information System (INIS)

Schuetrumpf, B; Maruhn, J A; Klatt, M A; Mecke, K; Reinhard, P-G; Iida, K

2013-01-01

We present simulations of neutron-rich matter at subnuclear densities, like supernova matter, with the time-dependent Hartree-Fock approximation at temperatures of several MeV. The initial state consists of α particles randomly distributed in space that have a Maxwell-Boltzmann distribution in momentum space. Adding a neutron background initialized with Fermi distributed plane waves the calculations reflect a reasonable approximation of astrophysical matter. This matter evolves into spherical, rod-like, and slab-like shapes and mixtures thereof. The simulations employ a full Skyrme interaction in a periodic three-dimensional grid. By an improved morphological analysis based on Minkowski functionals, all eight pasta shapes can be uniquely identified by the sign of only two valuations, namely the Euler characteristic and the integral mean curvature.

Time-Dependent Hartree-Fock Approach to Nuclear Pasta at Finite Temperature

Science.gov (United States)

Schuetrumpf, B.; Klatt, M. A.; Iida, K.; Maruhn, J. A.; Mecke, K.; Reinhard, P.-G.

2013-03-01

We present simulations of neutron-rich matter at subnuclear densities, like supernova matter, with the time-dependent Hartree-Fock approximation at temperatures of several MeV. The initial state consists of α particles randomly distributed in space that have a Maxwell-Boltzmann distribution in momentum space. Adding a neutron background initialized with Fermi distributed plane waves the calculations reflect a reasonable approximation of astrophysical matter. This matter evolves into spherical, rod-like, and slab-like shapes and mixtures thereof. The simulations employ a full Skyrme interaction in a periodic three-dimensional grid. By an improved morphological analysis based on Minkowski functionals, all eight pasta shapes can be uniquely identified by the sign of only two valuations, namely the Euler characteristic and the integral mean curvature.

Skill of real-time operational forecasts with the APCC multi-model ensemble prediction system during the period 2008-2015

Science.gov (United States)

Min, Young-Mi; Kryjov, Vladimir N.; Oh, Sang Myeong; Lee, Hyun-Ju

2017-12-01

This paper assesses the real-time 1-month lead forecasts of 3-month (seasonal) mean temperature and precipitation on a monthly basis issued by the Asia-Pacific Economic Cooperation Climate Center (APCC) for 2008-2015 (8 years, 96 forecasts). It shows the current level of the APCC operational multi-model prediction system performance. The skill of the APCC forecasts strongly depends on seasons and regions that it is higher for the tropics and boreal winter than for the extratropics and boreal summer due to direct effects and remote teleconnections from boundary forcings. There is a negative relationship between the forecast skill and its interseasonal variability for both variables and the forecast skill for precipitation is more seasonally and regionally dependent than that for temperature. The APCC operational probabilistic forecasts during this period show a cold bias (underforecasting of above-normal temperature and overforecasting of below-normal temperature) underestimating a long-term warming trend. A wet bias is evident for precipitation, particularly in the extratropical regions. The skill of both temperature and precipitation forecasts strongly depends upon the ENSO strength. Particularly, the highest forecast skill noted in 2015/2016 boreal winter is associated with the strong forcing of an extreme El Nino event. Meanwhile, the relatively low skill is associated with the transition and/or continuous ENSO-neutral phases of 2012-2014. As a result the skill of real-time forecast for boreal winter season is higher than that of hindcast. However, on average, the level of forecast skill during the period 2008-2015 is similar to that of hindcast.

Formal Specification and Verification of Real-Time Multi-Agent Systems using Timed-Arc Petri Nets

OpenAIRE

QASIM, A.; KAZMI, S. A. R.; FAKHIR, I.

2015-01-01

In this study we have formally specified and verified the actions of communicating real-time software agents (RTAgents). Software agents are expected to work autonomously and deal with unfamiliar situations astutely. Achieving cent percent test cases coverage for these agents has always been a problem due to limited resources. Also a high degree of dependability and predictability is expected from real-time software agents. In this research we have used Timed-Arc Petri Net...

In situ targeting TEM8 via immune response and polypeptide recognition by wavelength-modulated surface plasmon resonance biosensor

Science.gov (United States)

Wang, Yimin; Luo, Zewei; Liu, Kunping; Wang, Jie; Duan, Yixiang

2016-01-01

There is an increasing interest in real-time and in situ monitoring of living cell activities in life science and medicine. This paper reports a whole cell sensing protocol over the interface of Au film coupled in a wavelength-modulated surface plasmon resonance (WMSPR) biosensor. With dual parabolic mirrors integrated in the sensor, the compact and miniaturized instrument shows satisfactory refractive index sensitivity (2220 nm/RIU) and a high resolution of resonance wavelength shift of 0.3 nm to liquid samples. The affinity interactions between the biomarker of human tumor endothelial marker 8 (TEM8) and antibody (Ab) or specific polypeptide (PEP) were firstly introduced to WMSPR biosensor analysis. Both the interaction events of Ab-cell and PEP-cell over the Au film interface can be recognized by the sensor and the balance time of interactions is about 20 min. The concentration range of Ab for quantitative monitoring of the TEM8 expression on human colon carcinoma SW620 cells was investigated. The present low-cost and time-saving method provides a time resolution of binding specificity between Ab/PEP and TEM8 for real-time analysis of antigen on living tumor cell surface. PMID:26822761

Diagnosis of bacteremia in pediatric oncologic patients by in-house real-time PCR.

Science.gov (United States)

Quiles, Milene Gonçalves; Menezes, Liana Carballo; Bauab, Karen de Castro; Gumpl, Elke Kreuscher; Rocchetti, Talita Trevizani; Palomo, Flavia Silva; Carlesse, Fabianne; Pignatari, Antonio Carlos Campos

2015-07-23

Infections are the major cause of morbidity and mortality in children with cancer. Gaining a favorable prognosis for these patients depends on selecting the appropriate therapy, which in turn depends on rapid and accurate microbiological diagnosis. This study employed real-time PCR (qPCR) to identify the main pathogens causing bloodstream infection (BSI) in patients treated at the Pediatric Oncology Institute IOP-GRAACC-UNIFESP-Brazil. Antimicrobial resistance genes were also investigated using this methodology. A total of 248 samples from BACTEC® blood culture bottles and 99 whole-blood samples collected in tubes containing EDTA K2 Gel were isolated from 137 patients. All samples were screened by specific Gram probes for multiplex qPCR. Seventeen sequences were evaluated using gender-specific TaqMan probes and the resistance genes bla SHV, bla TEM, bla CTX, bla KPC, bla IMP, bla SPM, bla VIM, vanA, vanB and mecA were detected using the SYBR Green method. Positive qPCR results were obtained in 112 of the blood culture bottles (112/124), and 90 % agreement was observed between phenotypic and molecular microbial detection methods. For bacterial and fungal identification, the performance test showed: sensitivity 87 %; specificity 91 %; NPV 90 %; PPV 89 % and accuracy of 89 % when compared with the phenotypic method. The mecA gene was detected in 37 samples, extended-spectrum β-lactamases were detected in six samples and metallo-β-lactamase coding genes in four samples, with 60 % concordance between the two methods. The qPCR on whole blood detected eight samples possessing the mecA gene and one sample harboring the vanB gene. The bla KPC, bla VIM, bla IMP and bla SHV genes were not detected in this study. Real-time PCR is a useful tool in the early identification of pathogens and antimicrobial resistance genes from bloodstream infections of pediatric oncologic patients.

Differential dependence on N-glycosylation of anthrax toxin receptors CMG2 and TEM8.

Directory of Open Access Journals (Sweden)

Sarah Friebe

Full Text Available ANTXR 1 and 2, also known as TEM8 and CMG2, are two type I membrane proteins, which have been extensively studied for their role as anthrax toxin receptors, but with a still elusive physiological function. Here we have analyzed the importance of N-glycosylation on folding, trafficking and ligand binding of these closely related proteins. We find that TEM8 has a stringent dependence on N-glycosylation. The presence of at least one glycan on each of its two extracellular domains, the vWA and Ig-like domains, is indeed necessary for efficient trafficking to the cell surface. In the absence of any N-linked glycans, TEM8 fails to fold correctly and is recognized by the ER quality control machinery. Expression of N-glycosylation mutants reveals that CMG2 is less vulnerable to sugar loss. The absence of N-linked glycans in one of the extracellular domains indeed has little impact on folding, trafficking or receptor function of the wild type protein expressed in tissue culture cells. N-glycans do, however, seem required in primary fibroblasts from human patients. Here, the presence of N-linked sugars increases the tolerance to mutations in cmg2 causing the rare genetic disease Hyaline Fibromatosis Syndrome. It thus appears that CMG2 glycosylation provides a buffer towards genetic variation by promoting folding of the protein in the ER lumen.

Real-time change detection in data streams with FPGAs

International Nuclear Information System (INIS)

Vega, J.; Dormido-Canto, S.; Cruz, T.; Ruiz, M.; Barrera, E.; Castro, R.; Murari, A.; Ochando, M.

2014-01-01

Highlights: • Automatic recognition of changes in data streams of multidimensional signals. • Detection algorithm based on testing exchangeability on-line. • Real-time and off-line applicability. • Real-time implementation in FPGAs. - Abstract: The automatic recognition of changes in data streams is useful in both real-time and off-line data analyses. This article shows several effective change-detecting algorithms (based on martingales) and describes their real-time applicability in the data acquisition systems through the use of Field Programmable Gate Arrays (FPGA). The automatic event recognition system is absolutely general and it does not depend on either the particular event to detect or the specific data representation (waveforms, images or multidimensional signals). The developed approach provides good results for change detection in both the temporal evolution of profiles and the two-dimensional spatial distribution of volume emission intensity. The average computation time in the FPGA is 210 μs per profile

Is the TEM obsolescent?

International Nuclear Information System (INIS)

Williams, D.B.

2002-01-01

Full text: The TEM has undergone many revolutions since its invention 70 years ago, but is now a very mature instrument. The major functions of imaging, diffraction and analysis were invented decades ago. Much of the instrument development in the last 20 years has come in peripheral improvements such as ease of operation and computer control which, nevertheless, have made no substantial differences to basic operational methods. The TEM remains a predominantly manual instrument, still providing analog viewing and recording, well into the digital age. Indeed any operator of a Siemens Elmiskop 1 TEM from the 1950s would be more than skilled enough to operate a modern FEG TEM, with little more than a few minutes of training. It is arguable that no other cutting-edge scientific instrument is so basically unchanged in its method of operation over the last five decades, as the TEM. This state of affairs is a recipe for obsolescence. Students today are not interested in mastering the complexities of balancing potentiometers (which are still necessary for good centered dark-field operation) or manipulating sets of tilt controls to move from to , while fighting to maintain eucentricity and a recognizable image on the screen at 200 kX. Students are already masters of the mouse, keyboard or joystick and expect information to be generated, stored, processed and analyzed rapidly and efficiently under full computer control. We need to provide today's students with an instrument to challenge their skills, not those of their parents. There is nothing preventing the creation of a TEM that is under full computer control, except perhaps the notion that the TEM is an instrument worthy of mastery per se, rather than being simply a tool for the characterization of materials. In contrast, the SEM has never been seen as a 'real' electron microscope and consequently has found its way into many more research, education and commercial operations than the TEM. The SEM has also evolved

Rapid screening of β-Globin gene mutations by Real-Time PCR in ...

African Journals Online (AJOL)

Introduction of the real time PCR has made a revolution in the time taken for the PCR reactions. We present a method for the diagnosis of the common mutations of the B-thalassemia in Egyptian children & families. The procedure depends on the real-time PCR using specific fluorescently labeled hybridization probes.

Process algebra with timing : real time and discrete time

NARCIS (Netherlands)

Baeten, J.C.M.; Middelburg, C.A.; Bergstra, J.A.; Ponse, A.J.; Smolka, S.A.

2001-01-01

We present real time and discrete time versions of ACP with absolute timing and relative timing. The starting-point is a new real time version with absolute timing, called ACPsat, featuring urgent actions and a delay operator. The discrete time versions are conservative extensions of the discrete

Process algebra with timing: Real time and discrete time

NARCIS (Netherlands)

Baeten, J.C.M.; Middelburg, C.A.

1999-01-01

We present real time and discrete time versions of ACP with absolute timing and relative timing. The startingpoint is a new real time version with absolute timing, called ACPsat , featuring urgent actions and a delay operator. The discrete time versions are conservative extensions of the discrete

Real time capable infrared thermography for ASDEX Upgrade

Energy Technology Data Exchange (ETDEWEB)

Sieglin, B., E-mail: Bernhard.Sieglin@ipp.mpg.de; Faitsch, M.; Herrmann, A.; Brucker, B.; Eich, T.; Kammerloher, L.; Martinov, S. [Max-Planck Institute for Plasma Physics, Boltzmannstr. 2, D-85748 Garching (Germany)

2015-11-15

Infrared (IR) thermography is widely used in fusion research to study power exhaust and incident heat load onto the plasma facing components. Due to the short pulse duration of today’s fusion experiments, IR systems have mostly been designed for off-line data analysis. For future long pulse devices (e.g., Wendelstein 7-X, ITER), a real time evaluation of the target temperature and heat flux is mandatory. This paper shows the development of a real time capable IR system for ASDEX Upgrade. A compact IR camera has been designed incorporating the necessary magnetic and electric shielding for the detector, cooler assembly. The camera communication is based on the Camera Link industry standard. The data acquisition hardware is based on National Instruments hardware, consisting of a PXIe chassis inside and a fibre optical connected industry computer outside the torus hall. Image processing and data evaluation are performed using real time LabVIEW.

Real-time radiography

International Nuclear Information System (INIS)

Bossi, R.H.; Oien, C.T.

1981-01-01

Real-time radiography is used for imaging both dynamic events and static objects. Fluorescent screens play an important role in converting radiation to light, which is then observed directly or intensified and detected. The radiographic parameters for real-time radiography are similar to conventional film radiography with special emphasis on statistics and magnification. Direct-viewing fluoroscopy uses the human eye as a detector of fluorescent screen light or the light from an intensifier. Remote-viewing systems replace the human observer with a television camera. The remote-viewing systems have many advantages over the direct-viewing conditions such as safety, image enhancement, and the capability to produce permanent records. This report reviews real-time imaging system parameters and components

Real-time vision systems

Energy Technology Data Exchange (ETDEWEB)

Johnson, R.; Hernandez, J.E.; Lu, Shin-yee [Lawrence Livermore National Lab., CA (United States)

1994-11-15

Many industrial and defence applications require an ability to make instantaneous decisions based on sensor input of a time varying process. Such systems are referred to as `real-time systems` because they process and act on data as it occurs in time. When a vision sensor is used in a real-time system, the processing demands can be quite substantial, with typical data rates of 10-20 million samples per second. A real-time Machine Vision Laboratory (MVL) was established in FY94 to extend our years of experience in developing computer vision algorithms to include the development and implementation of real-time vision systems. The laboratory is equipped with a variety of hardware components, including Datacube image acquisition and processing boards, a Sun workstation, and several different types of CCD cameras, including monochrome and color area cameras and analog and digital line-scan cameras. The equipment is reconfigurable for prototyping different applications. This facility has been used to support several programs at LLNL, including O Division`s Peacemaker and Deadeye Projects as well as the CRADA with the U.S. Textile Industry, CAFE (Computer Aided Fabric Inspection). To date, we have successfully demonstrated several real-time applications: bullet tracking, stereo tracking and ranging, and web inspection. This work has been documented in the ongoing development of a real-time software library.

Temperature dependence of grain boundary free energy and elastic constants

International Nuclear Information System (INIS)

Foiles, Stephen M.

2010-01-01

This work explores the suggestion that the temperature dependence of the grain boundary free energy can be estimated from the temperature dependence of the elastic constants. The temperature-dependent elastic constants and free energy of a symmetric Σ79 tilt boundary are computed for an embedded atom method model of Ni. The grain boundary free energy scales with the product of the shear modulus times the lattice constant for temperatures up to about 0.75 the melting temperature.

Temperature dependence of fluctuation time scales in spin glasses

DEFF Research Database (Denmark)

Kenning, Gregory G.; Bowen, J.; Sibani, Paolo

2010-01-01

Using a series of fast cooling protocols we have probed aging effects in the spin glass state as a function of temperature. Analyzing the logarithmic decay found at very long time scales within a simple phenomenological barrier model, leads to the extraction of the fluctuation time scale of the s...

Examining real-time time-dependent density functional theory nonequilibrium simulations for the calculation of electronic stopping power

Science.gov (United States)

Yost, Dillon C.; Yao, Yi; Kanai, Yosuke

2017-09-01

In ion irradiation processes, electronic stopping power describes the energy transfer rate from the irradiating ion to the target material's electrons. Due to the scarcity and significant uncertainties in experimental electronic stopping power data for materials beyond simple solids, there has been growing interest in the use of first-principles theory for calculating electronic stopping power. In recent years, advances in high-performance computing have opened the door to fully first-principles nonequilibrium simulations based on real-time time-dependent density functional theory (RT-TDDFT). While it has been demonstrated that the RT-TDDFT approach is capable of predicting electronic stopping power for a wide range of condensed matter systems, there has yet to be an exhaustive examination of the physical and numerical approximations involved and their effects on the calculated stopping power. We discuss the results of such a study for crystalline silicon with protons as irradiating ions. We examine the influences of key approximations in RT-TDDFT nonequilibrium simulations on the calculated electronic stopping power, including approximations related to basis sets, finite size effects, exchange-correlation approximation, pseudopotentials, and more. Finally, we propose a simple and efficient correction scheme to account for the contribution from core-electron excitations to the stopping power, as it was found to be significant for large proton velocities.

Real-time control of the plasma density profile on ASDEX upgrade

International Nuclear Information System (INIS)

Mlynek, Alexander

2010-01-01

The tokamak concept currently is the most promising approach to future power generation by controlled thermonuclear fusion. The spatial distribution of the particle density in the toroidally confined fusion plasma is of particular importance. This thesis work therefore focuses on the question as to what extent the shape of the density profile can be actively controlled by a feedback loop in the fusion experiment ASDEX Upgrade. There are basically two essential requirements for such feedback control of the density profile, which has been experimentally demonstrated within the scope of this thesis work: On the one hand, for this purpose the density profile must be continuously calculated under real-time constraints during a plasma discharge. The calculation of the density profile is based on the measurements of a sub-millimeter interferometer, which provides the line-integrated electron density along 5 chords through the plasma. Interferometric density measurements can suffer from counting errors by integer multiples of 2π when detecting the phase difference between a probing and a reference beam. As such measurement errors have severe impact on the reconstructed density profile, one major part of this work consists in the development of new readout electronics for the interferometer, which allows for detection of such measurement errors in real-time with high reliability. A further part of this work is the design of a computer algorithm which reconstructs the spatial distribution of the plasma density from the line-integrated measurements. This algorithm has to be implemented on a computer which communicates the measured data to other computers in real-time, especially to the tokamak control system. On the other hand, a second fundamental requirement for the successful implementation of a feedback controller is the identification of at least one actuator which enables a modification of the density profile. Here, electron cyclotron resonance heating (ECRH) has been

Real-time interactive treatment planning

International Nuclear Information System (INIS)

Otto, Karl

2014-01-01

The goal of this work is to develop an interactive treatment planning platform that permits real-time manipulation of dose distributions including DVHs and other dose metrics. The hypothesis underlying the approach proposed here is that the process of evaluating potential dose distribution options and deciding on the best clinical trade-offs may be separated from the derivation of the actual delivery parameters used for the patient’s treatment. For this purpose a novel algorithm for deriving an Achievable Dose Estimate (ADE) was developed. The ADE algorithm is computationally efficient so as to update dose distributions in effectively real-time while accurately incorporating the limits of what can be achieved in practice. The resulting system is a software environment for interactive real-time manipulation of dose that permits the clinician to rapidly develop a fully customized 3D dose distribution. Graphical navigation of dose distributions is achieved by a sophisticated method of identifying contributing fluence elements, modifying those elements and re-computing the entire dose distribution. 3D dose distributions are calculated in ∼2–20 ms. Including graphics processing overhead, clinicians may visually interact with the dose distribution (e.g. ‘drag’ a DVH) and display updates of the dose distribution at a rate of more than 20 times per second. Preliminary testing on various sites shows that interactive planning may be completed in ∼1–5 min, depending on the complexity of the case (number of targets and OARs). Final DVHs are derived through a separate plan optimization step using a conventional VMAT planning system and were shown to be achievable within 2% and 4% in high and low dose regions respectively. With real-time interactive planning trade-offs between Target(s) and OARs may be evaluated efficiently providing a better understanding of the dosimetric options available to each patient in static or adaptive RT. (paper)

Real-time gaze estimation via pupil center tracking

Directory of Open Access Journals (Sweden)

Cazzato Dario

2018-02-01

Full Text Available Automatic gaze estimation not based on commercial and expensive eye tracking hardware solutions can enable several applications in the fields of human computer interaction (HCI and human behavior analysis. It is therefore not surprising that several related techniques and methods have been investigated in recent years. However, very few camera-based systems proposed in the literature are both real-time and robust. In this work, we propose a real-time user-calibration-free gaze estimation system that does not need person-dependent calibration, can deal with illumination changes and head pose variations, and can work with a wide range of distances from the camera. Our solution is based on a 3-D appearance-based method that processes the images from a built-in laptop camera. Real-time performance is obtained by combining head pose information with geometrical eye features to train a machine learning algorithm. Our method has been validated on a data set of images of users in natural environments, and shows promising results. The possibility of a real-time implementation, combined with the good quality of gaze tracking, make this system suitable for various HCI applications.

Time-dependent two-temperature chemically non-equilibrium modelling of high-power Ar-N2 pulse-modulated inductively coupled plasmas at atmospheric pressure

International Nuclear Information System (INIS)

Tanaka, Yasunori

2006-01-01

A time-dependent, two-dimensional, two-temperature and chemical non-equilibrium model was developed for high-power Ar-N 2 pulse-modulated inductively coupled plasmas (PMICPs) at atmospheric pressure. The high-power PMICP is a new technique for sustaining high-power induction plasmas. It can control the plasma temperature and radical densities in the time domain. The PMICP promotes non-equilibrium effects by a sudden application of electric field, even in the high-power density plasmas. The developed model accounts separately for the time-dependent energy conservation equations of electrons and heavy particles. This model also considers reaction heat effects and energy transfer between electrons and heavy particles as well as enthalpy flow resulting from diffusion caused by the particle density gradient. Chemical non-equilibrium effects are also taken into account by solving time-dependent mass conservation equations for each particle, considering diffusion, convection and net production terms resulting from 30 chemical reactions. Transport and thermodynamic properties of Ar-N 2 plasmas are calculated self-consistently using the first order approximation of the Chapman-Enskog method at each position and iteration using the local particle composition, heavy particle temperature and electron temperature. This model is useful to discuss time evolution in temperature, gas flow fields and distribution of chemical species

Platform for high temperature materials (PHiTEM)

International Nuclear Information System (INIS)

Baluc, N.; Hoffelner, W.; Michler, J.

2007-01-01

Advanced energy power systems like Generation IV fission reactors, thermonuclear fusion reactors, solar thermal/solar chemical reactors, gas turbines and coal gasification systems require materials that can operate at high temperatures in extreme environments: irradiation, corrosion, unidirectional and cyclic loads. On the path to development of new and adequate high temperature materials, understanding of damage formation and evolution and of damage effects is indispensable. Damage of materials in components takes place on different time and length scales. Component failure is usually a macroscopic event. Macroscopic material properties and their changes with time (e.g., hardening, creep embrittlement, corrosion) are determined by the micro- to nano-properties of the material. The multi scale is an ambitious and challenging attempt to take these facts into consideration by developing an unified model of the material behaviour. This requires, however, dedicated tools to test and analyse materials on different scales. The platform for high temperatures materials is being set up within the framework of collaboration between the EPFL, the PSI and the EMPA. It has three main goals: 1) Establish a platform that allows the multi scale characterization of relationships between microstructure and mechanical properties of advanced, high temperature materials, with a focus on irradiated, i.e. radioactive, materials, by combining the use of a focused ion beam and a nano indentation device with multi scale modelling and simulations. 2) Use the methods developed and the results gained for existing materials for developing improved high temperature materials to be used in advanced and sustainable future energy power plants. 3) Become an attractive partner for industry by providing a wide knowledge base, flexibility in answering technical questions and skills to better understand damage in already existing plants and to support development of new products at the industrial scale

A real-time extension of density matrix embedding theory for non-equilibrium electron dynamics

Science.gov (United States)

Kretchmer, Joshua S.; Chan, Garnet Kin-Lic

2018-02-01

We introduce real-time density matrix embedding theory (DMET), a dynamical quantum embedding theory for computing non-equilibrium electron dynamics in strongly correlated systems. As in the previously developed static DMET, real-time DMET partitions the system into an impurity corresponding to the region of interest coupled to the surrounding environment, which is efficiently represented by a quantum bath of the same size as the impurity. In this work, we focus on a simplified single-impurity time-dependent formulation as a first step toward a multi-impurity theory. The equations of motion of the coupled impurity and bath embedding problem are derived using the time-dependent variational principle. The accuracy of real-time DMET is compared to that of time-dependent complete active space self-consistent field (TD-CASSCF) theory and time-dependent Hartree-Fock (TDHF) theory for a variety of quantum quenches in the single impurity Anderson model (SIAM), in which the Hamiltonian is suddenly changed (quenched) to induce a non-equilibrium state. Real-time DMET shows a marked improvement over the mean-field TDHF, converging to the exact answer even in the non-trivial Kondo regime of the SIAM. However, as expected from analogous behavior in static DMET, the constrained structure of the real-time DMET wavefunction leads to a slower convergence with respect to active space size, in the single-impurity formulation, relative to TD-CASSCF. Our initial results suggest that real-time DMET provides a promising framework to simulate non-equilibrium electron dynamics in which strong electron correlation plays an important role, and lays the groundwork for future multi-impurity formulations.

High-temperature in-situ TEM straining of the interaction with dislocations and particles for Cu-added ferritic stainless steel.

Science.gov (United States)

Kobayashi, Shuhei; Kaneko, Kenji; Yamada, Kazuhiro; Kikuchi, Masao; Kanno, Norihiro; Hamada, Junichi

2014-11-01

IntroductionCu is always present in the matrix when ferritic steels were prepared from ferrous scrap. When the ferritic steels are aged thermally, Cu precipitates start appear and disperse finely and homogeneously [1], which may make the steels strengthened by precipitation hardening. In this study, the interaction between Cu precipitates and dislocations was exmined via high-temperature in-situ TEM straining. ExperimentalCu-added ferritic stainless steel (Fe-18.4%Cr-1.5%Cu) was used in the present study. Specimen was aged at1073 K for 360 ks. Samples for TEM observation were prepared by focused ion beam (FIB; Quanta 3D 200i) method. Microstructure of specimen was analyzed by JEM-3200FSK and high-temperature in-situ TEM straining was conducted using JEM-1300NEF. Results and discussionInteraction between Cu precipitates and dislocation is seen from consecutive TEM images acquired by in-situ TEM straining at 1073 K, as shown in Fig.1. The size of Cu precipitates was about 70 nm and several dislocations were present within the field of view. In particular, progressing dislocations contacted with the Cu precipitate at right angle, as indicated by arrows in Fig.1 (b) to (d). This result implies that there is an attractive interaction between dislocations and the Cu precipitate. This is attributed to the fact that Stress field of dislocations was easily relaxed in interface between the Cu precipitate and matrix because of lattice and interface diffusion as well as slip in the interface [2,3]. Furthermore, dislocations pass through the particle after contacting it, so that the interaction with dislocations and particles should be explained by Srolovitz mechanism [4].jmicro;63/suppl_1/i28/DFU083F1F1DFU083F1Fig. 1.TEM images foucused on interaction with dislocations and partticles. © The Author 2014. Published by Oxford University Press on behalf of The Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Memory controllers for real-time embedded systems predictable and composable real-time systems

CERN Document Server

Akesson, Benny

2012-01-01

  Verification of real-time requirements in systems-on-chip becomes more complex as more applications are integrated. Predictable and composable systems can manage the increasing complexity using formal verification and simulation.  This book explains the concepts of predictability and composability and shows how to apply them to the design and analysis of a memory controller, which is a key component in any real-time system. This book is generally intended for readers interested in Systems-on-Chips with real-time applications.   It is especially well-suited for readers looking to use SDRAM memories in systems with hard or firm real-time requirements. There is a strong focus on real-time concepts, such as predictability and composability, as well as a brief discussion about memory controller architectures for high-performance computing. Readers will learn step-by-step how to go from an unpredictable SDRAM memory, offering highly variable bandwidth and latency, to a predictable and composable shared memory...

Real-time pricing when some consumers resist in saving electricity

International Nuclear Information System (INIS)

Salies, Evens

2013-01-01

Successful real-time electricity pricing depends firstly upon consumers' willingness to subscribe to such terms and, secondly, on their ability to curb consumption levels. The present paper addresses both issues by considering consumers differentiated by their electricity saving costs, half of whom resist saving electricity. We demonstrate that when consumers are free to adopt real-time prices, producers prefer charging inefficient prices and, in so doing, discriminate against that portion of the consumer population which faces no saving costs. We also find that efficient marginal cost pricing is feasible, but is incompatible with mass adoption of real-time prices. - Highlights: • We model consumers switching from uniform to real-time electricity pricing (RTP). • Half the consumer population is pro-RTP and half resists saving electricity. • Efficient RTP is feasible but is incompatible with mass adoption

TEM turbulence optimisation in stellarators

Science.gov (United States)

Proll, J. H. E.; Mynick, H. E.; Xanthopoulos, P.; Lazerson, S. A.; Faber, B. J.

2016-01-01

With the advent of neoclassically optimised stellarators, optimising stellarators for turbulent transport is an important next step. The reduction of ion-temperature-gradient-driven turbulence has been achieved via shaping of the magnetic field, and the reduction of trapped-electron mode (TEM) turbulence is addressed in the present paper. Recent analytical and numerical findings suggest TEMs are stabilised when a large fraction of trapped particles experiences favourable bounce-averaged curvature. This is the case for example in Wendelstein 7-X (Beidler et al 1990 Fusion Technol. 17 148) and other Helias-type stellarators. Using this knowledge, a proxy function was designed to estimate the TEM dynamics, allowing optimal configurations for TEM stability to be determined with the STELLOPT (Spong et al 2001 Nucl. Fusion 41 711) code without extensive turbulence simulations. A first proof-of-principle optimised equilibrium stemming from the TEM-dominated stellarator experiment HSX (Anderson et al 1995 Fusion Technol. 27 273) is presented for which a reduction of the linear growth rates is achieved over a broad range of the operational parameter space. As an important consequence of this property, the turbulent heat flux levels are reduced compared with the initial configuration.

A New Generation of Real-Time Systems in the JET Tokamak

Science.gov (United States)

Alves, Diogo; Neto, Andre C.; Valcarcel, Daniel F.; Felton, Robert; Lopez, Juan M.; Barbalace, Antonio; Boncagni, Luca; Card, Peter; De Tommasi, Gianmaria; Goodyear, Alex; Jachmich, Stefan; Lomas, Peter J.; Maviglia, Francesco; McCullen, Paul; Murari, Andrea; Rainford, Mark; Reux, Cedric; Rimini, Fernanda; Sartori, Filippo; Stephen, Adam V.; Vega, Jesus; Vitelli, Riccardo; Zabeo, Luca; Zastrow, Klaus-Dieter

2014-04-01

Recently, a new recipe for developing and deploying real-time systems has become increasingly adopted in the JET tokamak. Powered by the advent of x86 multi-core technology and the reliability of JET's well established Real-Time Data Network (RTDN) to handle all real-time I/O, an official Linux vanilla kernel has been demonstrated to be able to provide real-time performance to user-space applications that are required to meet stringent timing constraints. In particular, a careful rearrangement of the Interrupt ReQuests' (IRQs) affinities together with the kernel's CPU isolation mechanism allows one to obtain either soft or hard real-time behavior depending on the synchronization mechanism adopted. Finally, the Multithreaded Application Real-Time executor (MARTe) framework is used for building applications particularly optimised for exploring multi-core architectures. In the past year, four new systems based on this philosophy have been installed and are now part of JET's routine operation. The focus of the present work is on the configuration aspects that enable these new systems' real-time capability. Details are given about the common real-time configuration of these systems, followed by a brief description of each system together with results regarding their real-time performance. A cycle time jitter analysis of a user-space MARTe based application synchronizing over a network is also presented. The goal is to compare its deterministic performance while running on a vanilla and on a Messaging Real time Grid (MRG) Linux kernel.

Hardware/Software Data Acquisition System for Real Time Cell Temperature Monitoring in Air-Cooled Polymer Electrolyte Fuel Cells.

Science.gov (United States)

Segura, Francisca; Bartolucci, Veronica; Andújar, José Manuel

2017-07-09

This work presents a hardware/software data acquisition system developed for monitoring the temperature in real time of the cells in Air-Cooled Polymer Electrolyte Fuel Cells (AC-PEFC). These fuel cells are of great interest because they can carry out, in a single operation, the processes of oxidation and refrigeration. This allows reduction of weight, volume, cost and complexity of the control system in the AC-PEFC. In this type of PEFC (and in general in any PEFC), the reliable monitoring of temperature along the entire surface of the stack is fundamental, since a suitable temperature and a regular distribution thereof, are key for a better performance of the stack and a longer lifetime under the best operating conditions. The developed data acquisition (DAQ) system can perform non-intrusive temperature measurements of each individual cell of an AC-PEFC stack of any power (from watts to kilowatts). The stack power is related to the temperature gradient; i.e., a higher power corresponds to a higher stack surface, and consequently higher temperature difference between the coldest and the hottest point. The developed DAQ system has been implemented with the low-cost open-source platform Arduino, and it is completed with a modular virtual instrument that has been developed using NI LabVIEW. Temperature vs time evolution of all the cells of an AC-PEFC both together and individually can be registered and supervised. The paper explains comprehensively the developed DAQ system together with experimental results that demonstrate the suitability of the system.

Hardware/Software Data Acquisition System for Real Time Cell Temperature Monitoring in Air-Cooled Polymer Electrolyte Fuel Cells

Directory of Open Access Journals (Sweden)

Francisca Segura

2017-07-01

Full Text Available This work presents a hardware/software data acquisition system developed for monitoring the temperature in real time of the cells in Air-Cooled Polymer Electrolyte Fuel Cells (AC-PEFC. These fuel cells are of great interest because they can carry out, in a single operation, the processes of oxidation and refrigeration. This allows reduction of weight, volume, cost and complexity of the control system in the AC-PEFC. In this type of PEFC (and in general in any PEFC, the reliable monitoring of temperature along the entire surface of the stack is fundamental, since a suitable temperature and a regular distribution thereof, are key for a better performance of the stack and a longer lifetime under the best operating conditions. The developed data acquisition (DAQ system can perform non-intrusive temperature measurements of each individual cell of an AC-PEFC stack of any power (from watts to kilowatts. The stack power is related to the temperature gradient; i.e., a higher power corresponds to a higher stack surface, and consequently higher temperature difference between the coldest and the hottest point. The developed DAQ system has been implemented with the low-cost open-source platform Arduino, and it is completed with a modular virtual instrument that has been developed using NI LabVIEW. Temperature vs time evolution of all the cells of an AC-PEFC both together and individually can be registered and supervised. The paper explains comprehensively the developed DAQ system together with experimental results that demonstrate the suitability of the system.

Time-temperature dependent variations in beta-carotene contents in carrot using different spectrophotometric techniques

Science.gov (United States)

Ullah, Rahat; Khan, Saranjam; Shah, Attaullah; Ali, Hina; Bilal, Muhammad

2018-05-01

The current study presents time dependent variations in the concentration of beta-carotene in carrot under different storage-temperature conditions using UV–VIS and Raman spectrophotometric techniques. The UV–VIS absorption spectra of beta-carotene extracted from carrot shows three distinct absorption peaks at 442, 467, and 500 nm with maximum absorption at 467 nm. These absorption peaks are very much reproducible and are assigned to β-carotene. Similarly, Raman spectra of carrot samples also confirmed the three main Raman peaks of beta-carotene at shift positions 1003, 1150, and 1515 cm‑1. An overall decrease in beta-carotene content has been observed for time-temperature conditions. These results depict a decrease of about 40% in the content of beta-carotene when carrot samples were stored in a refrigerator (4 °C) for the first 20 d, whereas a decrease of about 25% was observed when carrot samples were stored in a freezer (‑16 °C) for the same period. The objective of this study is to investigate the possible use of Raman spectroscopy and UV–VIS spectroscopy for quick and detailed analysis of changes (degradation) in beta-carotene content associated with time and temperature in storage (frozen foods) in order to promote quality foods for consumers. Future study with a greater focus on the concentration/content of beta-carotene in other fruits/vegetables is also desirable.

Real-time movie image enhancement in NMR

International Nuclear Information System (INIS)

Doyle, M.; Mansfield, P.

1986-01-01

Clinical NMR motion picture (movie) images can now be produced routinely in real-time by ultra-high-speed echo-planar imaging (EPI). The single-shot image quality depends on both pixel resolution and signal-to-noise ratio (S/N), both factors being intertradeable. If image S/N is sacrificed rather than resolution, it is shown that S/N may be greatly enhanced subsequently without vitiating spatial resolution or foregoing real motional effects when the object motion is periodic. This is achieved by a Fourier filtering process. Experimental results are presented which demonstrate the technique for a normal functioning heart. (author)

Essays in real-time forecasting

OpenAIRE

Liebermann, Joelle

2012-01-01

This thesis contains three essays in the field of real-time econometrics, and more particularlyforecasting.The issue of using data as available in real-time to forecasters, policymakers or financialmarkets is an important one which has only recently been taken on board in the empiricalliterature. Data available and used in real-time are preliminary and differ from ex-postrevised data, and given that data revisions may be quite substantial, the use of latestavailable instead of real-time can s...

Exploration of shallow subsurface resistivity structure using a portable TEM system: TEM-FAST prosystem; Kan`igata TEM ho sochi TEM-FAST prosystem ni yoru senbu hiteiko chosa

Energy Technology Data Exchange (ETDEWEB)

Miura, Y; Kumekawa, Y; Takasugi, S [GERD Geothermal Energy Research and Development Co. Ltd., Tokyo (Japan)

1997-05-27

Discussions were given on effectiveness of the TEM-FAST ProSystem which is a portable TEM system developed recently for use in exploration of shallow subsurface resistivity. The system consists of a loop type antenna, the TEM-FAST as the main equipment, and a host computer, the host computer controlling the entire system. The system acquires transient response data in secondary induced magnetic fields lasting 4 {mu} sec to 1 m sec. The number of data is 5490 stacks in one measurement, and the data acquisition time is about three minutes. Measurements were carried out by using the TEM-FAST in the vicinity of a well, whose results were compared with those of electric logging, and discussions were given on them. Although the electric logging results had no data available for depths shallower than 35 m, the measurement results from the TEM-FAST were found highly harmonious with those of the electric logging. In addition, there were transmission and telephone lines in locations about 10 m away from the well during the measurement, but extremely high data quality was discovered. 6 refs., 7 figs., 1 tab.

Complete FDTD analysis of microwave heating processes in frequency-dependent and temperature dependent media

Energy Technology Data Exchange (ETDEWEB)

Torres, F.; Jecko, B. [Univ. de Limoges (France). Inst. de Recherche en Communications Optiques et Microondes

1997-01-01

It is well known that the temperature rise in a material modifies its physical properties and, particularly, its dielectric permittivity. The dissipated electromagnetic power involved in microwave heating processes depending on {var_epsilon}({omega}), the electrical characteristics of the heated media must vary with the temperature to achieve realistic simulations. In this paper, the authors present a fast and accurate algorithm allowing, through a combined electromagnetic and thermal procedure, to take into account the influence of the temperature on the electrical properties of materials. First, the temperature dependence of the complex permittivity ruled by a Debye relaxation equation is investigated, and a realistic model is proposed and validated. Then, a frequency-dependent finite-differences time-domain ((FD){sup 2}TD) method is used to assess the instantaneous electromagnetic power lost by dielectric hysteresis. Within the same iteration, a time-scaled form of the heat transfer equation allows one to calculate the temperature distribution in the heated medium and then to correct the dielectric properties of the material using the proposed model. These new characteristics will be taken into account by the EM solver at the next iteration. This combined algorithm allows a significant reduction of computation time. An application to a microwave oven is proposed.

Modeling solvation effects in real-space and real-time within density functional approaches

Energy Technology Data Exchange (ETDEWEB)

Delgado, Alain [Istituto Nanoscienze - CNR, Centro S3, via Campi 213/A, 41125 Modena (Italy); Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear, Calle 30 # 502, 11300 La Habana (Cuba); Corni, Stefano; Pittalis, Stefano; Rozzi, Carlo Andrea [Istituto Nanoscienze - CNR, Centro S3, via Campi 213/A, 41125 Modena (Italy)

2015-10-14

The Polarizable Continuum Model (PCM) can be used in conjunction with Density Functional Theory (DFT) and its time-dependent extension (TDDFT) to simulate the electronic and optical properties of molecules and nanoparticles immersed in a dielectric environment, typically liquid solvents. In this contribution, we develop a methodology to account for solvation effects in real-space (and real-time) (TD)DFT calculations. The boundary elements method is used to calculate the solvent reaction potential in terms of the apparent charges that spread over the van der Waals solute surface. In a real-space representation, this potential may exhibit a Coulomb singularity at grid points that are close to the cavity surface. We propose a simple approach to regularize such singularity by using a set of spherical Gaussian functions to distribute the apparent charges. We have implemented the proposed method in the OCTOPUS code and present results for the solvation free energies and solvatochromic shifts for a representative set of organic molecules in water.

Full integrated system of real-time monitoring based on distributed architecture for the high temperature engineering test reactor (HTTR)

International Nuclear Information System (INIS)

Subekti, Muhammad; Ohno, Tomio; Kudo, Kazuhiko; Takamatsu, Kuniyoshi; Nabeshima, Kunihiko

2005-01-01

A new monitoring system scheme based on distributed architecture for the High Temperature Engineering Test Reactor (HTTR) is proposed to assure consistency of the real-time process of expanded system. A distributed monitoring task on client PCs as an alternative architecture maximizes the throughput and capabilities of the system even if the monitoring tasks suffer a shortage of bandwidth. The prototype of the on-line monitoring system has been developed successfully and will be tested at the actual HTTR site. (author)

Ovation Prime Real-Time

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Ovation Prime Real-Time (OPRT) product is a real-time forecast and nowcast model of auroral power and is an operational implementation of the work by Newell et...

Temperature dependence on the time and momentum spectra in germanium

International Nuclear Information System (INIS)

Schultz, P.J.; MacKenzie, I.K.

1982-01-01

Recent measurements using the slow-#betta# + beam at Brookhaven, have suggested a thermally activated trapping mechanism which inhibited positron diffusion in single-crystal Ge. Supporting evidence has now been obtained from both Doppler broadening and lifetime measurements but, in both cases, the temperature dependence was so weak that it required the use of dual digital stabilization and unusual statistical precision in both types of spectrometry. (Auth.)

An important role of temperature dependent scattering time in understanding the high temperature thermoelectric behavior of strongly correlated system: La0.75Ba0.25CoO3.

Science.gov (United States)

Singh, Saurabh; Kumar, Devendra; Pandey, Sudhir K

2017-03-15

In the present work, we report the temperature dependent thermopower (α) behavior of La 0.75 Ba 0.25 CoO 3 compound in the temperature range 300-600 K. Using the Heikes formula, the estimated value of α corresponding to high-spin configuration of Co 3+ and Co 4+ ions is found to be  ∼16 [Formula: see text], which is close to the experimental value, ∼13 [Formula: see text], observed at  ∼600 K. The temperature dependent TE behavior of the compound is studied by combining the WIEN2K and BoltzTrap code. The self consistency field calculations show that the compound have ferromagnetic ground state structure. The electronic structure calculations give half metallic characteristic with a small gap of  ∼50 meV for down spin channel. The large and positive value for down spin channel is obtained due to the unique band structure shown by this spin channel. The temperature dependent relaxation time for both the spin-channel charge carriers is considered to study the thermopower data in temperature range 300-600 K. For evaluation of α, almost linear values of [Formula: see text] and a non-linear values of [Formula: see text] are taken into account. By taking the temperature dependent values of relaxation time for both the spin channels, the calculated values of α using two current model are found to be in good agreement with experimental values in the temperature range 300-600 K. At 300 K, the calculated value of electrical conductivity by using the same value of relaxation time, i.e. 0.1 [Formula: see text] 10 -14 seconds for spin-up and [Formula: see text] seconds for spin-dn channel, is found to be equal to the experimentally reported value.

Time-dependent Hartree-Fock approach to nuclear ``pasta'' at finite temperature

Science.gov (United States)

Schuetrumpf, B.; Klatt, M. A.; Iida, K.; Maruhn, J. A.; Mecke, K.; Reinhard, P.-G.

2013-05-01

We present simulations of neutron-rich matter at subnuclear densities, like supernova matter, with the time-dependent Hartree-Fock approximation at temperatures of several MeV. The initial state consists of α particles randomly distributed in space that have a Maxwell-Boltzmann distribution in momentum space. Adding a neutron background initialized with Fermi distributed plane waves the calculations reflect a reasonable approximation of astrophysical matter. This matter evolves into spherical, rod-like, and slab-like shapes and mixtures thereof. The simulations employ a full Skyrme interaction in a periodic three-dimensional grid. By an improved morphological analysis based on Minkowski functionals, all eight pasta shapes can be uniquely identified by the sign of only two valuations, namely the Euler characteristic and the integral mean curvature. In addition, we propose the variance in the cell density distribution as a measure to distinguish pasta matter from uniform matter.

Ruggedized downhole tool for real-time measurements and uses thereof

Energy Technology Data Exchange (ETDEWEB)

Hess, Ryan Falcone; Lindblom, Scott C.; Yelton, William G.; Limmer, Steven J.; Boyle, Timothy J.; Cieslewski, Grzegorz

2018-01-09

The present invention relates to ruggedized downhole tools and sensors, as well as uses thereof. In particular, these tools can operate under extreme conditions and, therefore, allow for real-time measurements in geothermal reservoirs or other potentially harsh environments. One exemplary sensor includes a ruggedized ion selective electrode (ISE) for detecting tracer concentrations in real-time. In one embodiment, the ISE includes a solid, non-conductive potting material and an ion selective material, which are disposed in a temperature-resistant electrode body. Other electrode configurations, tools, and methods are also described.

Time-Dependent Wave Packet Dynamics Calculations of Cross Sections for Ultracold Scattering of Molecules

Science.gov (United States)

Huang, Jiayu; Liu, Shu; Zhang, Dong H.; Krems, Roman V.

2018-04-01

Because the de Broglie wavelength of ultracold molecules is very large, the cross sections for collisions of molecules at ultracold temperatures are always computed by the time-independent quantum scattering approach. Here, we report the first accurate time-dependent wave packet dynamics calculation for reactive scattering of ultracold molecules. Wave packet dynamics calculations can be applied to molecular systems with more dimensions and provide real-time information on the process of bond rearrangement and/or energy exchange in molecular collisions. Our work thus makes possible the extension of rigorous quantum calculations of ultracold reaction properties to polyatomic molecules and adds a new powerful tool for the study of ultracold chemistry.

Comparison of real-time SYBR green dengue assay with real-time taqman RT-PCR dengue assay and the conventional nested PCR for diagnosis of primary and secondary dengue infection

Science.gov (United States)

Paudel, Damodar; Jarman, Richard; Limkittikul, Kriengsak; Klungthong, Chonticha; Chamnanchanunt, Supat; Nisalak, Ananda; Gibbons, Robert; Chokejindachai, Watcharee

2011-01-01

Background: Dengue fever and dengue hemorrhagic fever are caused by dengue virus. Dengue infection remains a burning problem of many countries. To diagnose acute dengue in the early phase we improve the low cost, rapid SYBR green real time assay and compared the sensitivity and specificity with real time Taqman® assay and conventional nested PCR assay. Aims: To develop low cost, rapid and reliable real time SYBR green diagnostic dengue assay and compare with Taqman real-time assay and conventional nested PCR (modified Lanciotti). Materials and Methods: Eight cultured virus strains were diluted in tenth dilution down to undetectable level by the PCR to optimize the primer, temperature (annealing, and extension and to detect the limit of detection of the assay. Hundred and ninety three ELISA and PCR proved dengue clinical samples were tested with real time SYBR® Green assay, real time Taqman® assay to compare the sensitivity and specificity. Results: Sensitivity and specificity of real time SYBR® green dengue assay (84% and 66%, respectively) was almost comparable to those (81% and 74%) of Taqman real time PCR dengue assay. Real time SYBR® green RT-PCR was equally sensitive in primary and secondary infection while real time Taqman was less sensitive in the secondary infection. Sensitivity of real time Taqman on DENV3 (87%) was equal to SYBR green real time PCR dengue assay. Conclusion: We developed low cost rapid diagnostic SYBR green dengue assay. Further study is needed to make duplex primer assay for the serotyping of dengue virus. PMID:22363089

An SDRAM controller for real-time systems

DEFF Research Database (Denmark)

Lakis, Edgar; Schoeberl, Martin

2013-01-01

For real-time systems we need to statically determine worst-case execution times (WCET) of tasks to proof the schedulability of the system. To enable static WCET analysis, the platform needs to be time-predictable. The platform includes the processor, the caches, the memory system, the operating...... system, and the application software itself. All those components need to be timing analyzable. Current computers use DRAM as a cost effective main memory. However, these DRAM chips have timing requirements that depend on former accesses and also need to be refreshed to retain their content. Standard...... a base of the memory hierarchy for time-predictable systems....

VERSE - Virtual Equivalent Real-time Simulation

Science.gov (United States)

Zheng, Yang; Martin, Bryan J.; Villaume, Nathaniel

2005-01-01

Distributed real-time simulations provide important timing validation and hardware in the- loop results for the spacecraft flight software development cycle. Occasionally, the need for higher fidelity modeling and more comprehensive debugging capabilities - combined with a limited amount of computational resources - calls for a non real-time simulation environment that mimics the real-time environment. By creating a non real-time environment that accommodates simulations and flight software designed for a multi-CPU real-time system, we can save development time, cut mission costs, and reduce the likelihood of errors. This paper presents such a solution: Virtual Equivalent Real-time Simulation Environment (VERSE). VERSE turns the real-time operating system RTAI (Real-time Application Interface) into an event driven simulator that runs in virtual real time. Designed to keep the original RTAI architecture as intact as possible, and therefore inheriting RTAI's many capabilities, VERSE was implemented with remarkably little change to the RTAI source code. This small footprint together with use of the same API allows users to easily run the same application in both real-time and virtual time environments. VERSE has been used to build a workstation testbed for NASA's Space Interferometry Mission (SIM PlanetQuest) instrument flight software. With its flexible simulation controls and inexpensive setup and replication costs, VERSE will become an invaluable tool in future mission development.

Progress Report on Alloy 617 Time Dependent Allowables

Energy Technology Data Exchange (ETDEWEB)

Wright, Julie Knibloe [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-06-01

Time dependent allowable stresses are required in the ASME Boiler and Pressure Vessel Code for design of components in the temperature range where time dependent deformation (i.e., creep) is expected to become significant. There are time dependent allowable stresses in Section IID of the Code for use in the non-nuclear construction codes, however, there are additional criteria that must be considered in developing time dependent allowables for nuclear components. These criteria are specified in Section III NH. St is defined as the lesser of three quantities: 100% of the average stress required to obtain a total (elastic, plastic, primary and secondary creep) strain of 1%; 67% of the minimum stress to cause rupture; and 80% of the minimum stress to cause the initiation of tertiary creep. The values are reported for a range of temperatures and for time increments up to 100,000 hours. These values are determined from uniaxial creep tests, which involve the elevated temperature application of a constant load which is relatively small, resulting in deformation over a long time period prior to rupture. The stress which is the minimum resulting from these criteria is the time dependent allowable stress St. In this report data from a large number of creep and creep-rupture tests on Alloy 617 are analyzed using the ASME Section III NH criteria. Data which are used in the analysis are from the ongoing DOE sponsored high temperature materials program, form Korea Atomic Energy Institute through the Generation IV VHTR Materials Program and historical data from previous HTR research and vendor data generated in developing the alloy. It is found that the tertiary creep criterion determines St at highest temperatures, while the stress to cause 1% total strain controls at low temperatures. The ASME Section III Working Group on Allowable Stress Criteria has recommended that the uncertainties associated with determining the onset of tertiary creep and the lack of significant

Real-time interactive 3D manipulation of particles viewed in two orthogonal observation planes

DEFF Research Database (Denmark)

Perch-Nielsen, I.; Rodrigo, P.J.; Glückstad, J.

2005-01-01

The generalized phase contrast (GPC) method has been applied to transform a single TEM00 beam into a manifold of counterpropagating-beam traps capable of real-time interactive manipulation of multiple microparticles in three dimensions (3D). This paper reports on the use of low numerical aperture...... for imaging through each of the two opposing objective lenses. As a consequence of the large working distance, simultaneous monitoring of the trapped particles in a second orthogonal observation plane is demonstrated. (C) 2005 Optical Society of America....

Real-time individualization of the unified model of performance.

Science.gov (United States)

Liu, Jianbo; Ramakrishnan, Sridhar; Laxminarayan, Srinivas; Balkin, Thomas J; Reifman, Jaques

2017-12-01

Existing mathematical models for predicting neurobehavioural performance are not suited for mobile computing platforms because they cannot adapt model parameters automatically in real time to reflect individual differences in the effects of sleep loss. We used an extended Kalman filter to develop a computationally efficient algorithm that continually adapts the parameters of the recently developed Unified Model of Performance (UMP) to an individual. The algorithm accomplishes this in real time as new performance data for the individual become available. We assessed the algorithm's performance by simulating real-time model individualization for 18 subjects subjected to 64 h of total sleep deprivation (TSD) and 7 days of chronic sleep restriction (CSR) with 3 h of time in bed per night, using psychomotor vigilance task (PVT) data collected every 2 h during wakefulness. This UMP individualization process produced parameter estimates that progressively approached the solution produced by a post-hoc fitting of model parameters using all data. The minimum number of PVT measurements needed to individualize the model parameters depended upon the type of sleep-loss challenge, with ~30 required for TSD and ~70 for CSR. However, model individualization depended upon the overall duration of data collection, yielding increasingly accurate model parameters with greater number of days. Interestingly, reducing the PVT sampling frequency by a factor of two did not notably hamper model individualization. The proposed algorithm facilitates real-time learning of an individual's trait-like responses to sleep loss and enables the development of individualized performance prediction models for use in a mobile computing platform. © 2017 European Sleep Research Society.

Assessment of Real-Time Time-Dependent Density Functional Theory (RT-TDDFT) in Radiation Chemistry: Ionized Water Dimer.

Science.gov (United States)

Chalabala, Jan; Uhlig, Frank; Slavíček, Petr

2018-03-29

Ionization in the condensed phase and molecular clusters leads to a complicated chain of processes with coupled electron-nuclear dynamics. It is difficult to describe such dynamics with conventional nonadiabatic molecular dynamics schemes since the number of states swiftly increases as the molecular system grows. It is therefore attractive to use a direct electron and nuclear propagation such as the real-time time-dependent density functional theory (RT-TDDFT). Here we report a RT-TDDFT benchmark study on simulations of singly and doubly ionized states of a water monomer and dimer as a prototype for more complex processes in a condensed phase. We employed the RT-TDDFT based Ehrenfest molecular dynamics with a generalized gradient approximate (GGA) functional and compared it with wave-function-based surface hopping (SH) simulations. We found that the initial dynamics of a singly HOMO ionized water dimer is similar for both the RT-TDDFT/GGA and the SH simulations but leads to completely different reaction channels on a longer time scale. This failure is attributed to the self-interaction error in the GGA functionals and it can be avoided by using hybrid functionals with large fraction of exact exchange (represented here by the BHandHLYP functional). The simulations of doubly ionized states are reasonably described already at the GGA level. This suggests that the RT-TDDFT/GGA method could describe processes following the autoionization processes such as Auger emission, while its applicability to more complex processes such as intermolecular Coulombic decay remains limited.

Fundamental Constants in Physics and their Time Dependence

CERN Multimedia

CERN. Geneva

2008-01-01

In the Standard Model of Particle Physics we are dealing with 28 fundamental constants. In the experiments these constants can be measured, but theoretically they are not understood. I will discuss these constants, which are mostly mass parameters. Astrophysical measurements indicate that the finestructure constant is not a real constant, but depends on time. Grand unification then implies also a time variation of the QCD scale. Thus the masses of the atomic nuclei and the magnetic moments of the nuclei will depend on time. I proposed an experiment, which is currently done by Prof. Haensch in Munich and his group. The first results indicate a time dependence of the QCD scale. I will discuss the theoretical implications.

Frequency and temperature dependent mobility of a charged carrier and randomly interrupted strand

International Nuclear Information System (INIS)

Kumar, N.; Jayannavar, A.M.

1981-05-01

Randomly interrupted strand model of a one-dimensional conductor is considered. Exact analytical expression is obtained for the temperature dependent as mobility for a finite segment drawn at random, taking into account the reflecting barriers at the two open ends. The real part of mobility shows a broad resonance as a function of both frequency and tempeature, and vanishes quadratically in the dc limit. The frequency (temperature) maximum shifts to higher values for higher temperatures (frequencies). (author)

ISTTOK real-time architecture

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Ivo S., E-mail: ivoc@ipfn.ist.utl.pt; Duarte, Paulo; Fernandes, Horácio; Valcárcel, Daniel F.; Carvalho, Pedro J.; Silva, Carlos; Duarte, André S.; Neto, André; Sousa, Jorge; Batista, António J.N.; Hekkert, Tiago; Carvalho, Bernardo B.

2014-03-15

Highlights: • All real-time diagnostics and actuators were integrated in the same control platform. • A 100 μs control cycle was achieved under the MARTe framework. • Time-windows based control with several event-driven control strategies implemented. • AC discharges with exception handling on iron core flux saturation. • An HTML discharge configuration was developed for configuring the MARTe system. - Abstract: The ISTTOK tokamak was upgraded with a plasma control system based on the Advanced Telecommunications Computing Architecture (ATCA) standard. This control system was designed to improve the discharge stability and to extend the operational space to the alternate plasma current (AC) discharges as part of the ISTTOK scientific program. In order to accomplish these objectives all ISTTOK diagnostics and actuators relevant for real-time operation were integrated in the control system. The control system was programmed in C++ over the Multi-threaded Application Real-Time executor (MARTe) which provides, among other features, a real-time scheduler, an interrupt handler, an intercommunications interface between code blocks and a clearly bounded interface with the external devices. As a complement to the MARTe framework, the BaseLib2 library provides the foundations for the data, code introspection and also a Hypertext Transfer Protocol (HTTP) server service. Taking advantage of the modular nature of MARTe, the algorithms of each diagnostic data processing, discharge timing, context switch, control and actuators output reference generation, run on well-defined blocks of code named Generic Application Module (GAM). This approach allows reusability of the code, simplified simulation, replacement or editing without changing the remaining GAMs. The ISTTOK control system GAMs run sequentially each 100 μs cycle on an Intel{sup ®} Q8200 4-core processor running at 2.33 GHz located in the ATCA crate. Two boards (inside the ATCA crate) with 32 analog

ISTTOK real-time architecture

International Nuclear Information System (INIS)

Carvalho, Ivo S.; Duarte, Paulo; Fernandes, Horácio; Valcárcel, Daniel F.; Carvalho, Pedro J.; Silva, Carlos; Duarte, André S.; Neto, André; Sousa, Jorge; Batista, António J.N.; Hekkert, Tiago; Carvalho, Bernardo B.

2014-01-01

Highlights: • All real-time diagnostics and actuators were integrated in the same control platform. • A 100 μs control cycle was achieved under the MARTe framework. • Time-windows based control with several event-driven control strategies implemented. • AC discharges with exception handling on iron core flux saturation. • An HTML discharge configuration was developed for configuring the MARTe system. - Abstract: The ISTTOK tokamak was upgraded with a plasma control system based on the Advanced Telecommunications Computing Architecture (ATCA) standard. This control system was designed to improve the discharge stability and to extend the operational space to the alternate plasma current (AC) discharges as part of the ISTTOK scientific program. In order to accomplish these objectives all ISTTOK diagnostics and actuators relevant for real-time operation were integrated in the control system. The control system was programmed in C++ over the Multi-threaded Application Real-Time executor (MARTe) which provides, among other features, a real-time scheduler, an interrupt handler, an intercommunications interface between code blocks and a clearly bounded interface with the external devices. As a complement to the MARTe framework, the BaseLib2 library provides the foundations for the data, code introspection and also a Hypertext Transfer Protocol (HTTP) server service. Taking advantage of the modular nature of MARTe, the algorithms of each diagnostic data processing, discharge timing, context switch, control and actuators output reference generation, run on well-defined blocks of code named Generic Application Module (GAM). This approach allows reusability of the code, simplified simulation, replacement or editing without changing the remaining GAMs. The ISTTOK control system GAMs run sequentially each 100 μs cycle on an Intel ® Q8200 4-core processor running at 2.33 GHz located in the ATCA crate. Two boards (inside the ATCA crate) with 32 analog

ON THE ANISOTROPIC NORM OF DISCRETE TIME STOCHASTIC SYSTEMS WITH STATE DEPENDENT NOISE

Directory of Open Access Journals (Sweden)

Isaac Yaesh

2013-01-01

Full Text Available The purpose of this paper is to determine conditions for the bound-edness of the anisotropic norm of discrete-time linear stochastic sys-tems with state dependent noise. It is proved that these conditions canbe expressed in terms of the feasibility of a specific system of matrixinequalities.

Time-dependent electron temperature diagnostics for high-power aluminum z-pinch plasmas

International Nuclear Information System (INIS)

Sanford, T.W.L.; Nash, T.J.; Mock, R.C.

1996-08-01

Time-resolved x-ray pinhole photographs and time-integrated radially-resolved x-ray crystal-spectrometer measurements of azimuthally-symmetric aluminum-wire implosions suggest that the densest phase of the pinch is composed of a hot plasma core surrounded by a cooler plasma halo. The slope of the free-bound x-ray continuum, provides a time-resolved, model-independent diagnostic of the core electron temperature. A simultaneous measurement of the time-resolved K-shell line spectra provides the electron temperature of the spatially averaged plasma. Together, the two diagnostics support a 1-D Radiation-Hydrodynamic model prediction of a plasma whose thermalization on axis produces steep radial gradients in temperature, from temperatures in excess of a kilovolt in the core to below a kilovolt in the surrounding plasma halo

"Soft"or "hard" ionisation? Investigation of metastable gas temperature effect on direct analysis in real-time analysis of Voriconazole.

Science.gov (United States)

Lapthorn, Cris; Pullen, Frank

2009-01-01

The performance of the direct analysis in real-time (DART) technique was evaluated across a range of metastable gas temperatures for a pharmaceutical compound, Voriconazole, in order to investigate the effect of metastable gas temperature on molecular ion intensity and fragmentation. The DART source has been used to analyse a range of analytes and from a range of matrices including drugs in solid tablet form and preparations, active ingredients in ointment, naturally occurring plant alkaloids, flavours and fragrances, from thin layer chromatography (TLC) plates, melting point tubes and biological matrices including hair, urine and blood. The advantages of this technique include rapid analysis time (as little as 5 s), a reduction in sample preparation requirements, elimination of mobile phase requirement and analysis of samples not typically amenable to atmospheric pressure ionisation (API) techniques. This technology has therefore been proposed as an everyday tool for identification of components in crude organic reaction mixtures.

Real-Time EEG-Based Happiness Detection System

Directory of Open Access Journals (Sweden)

Noppadon Jatupaiboon

2013-01-01

Full Text Available We propose to use real-time EEG signal to classify happy and unhappy emotions elicited by pictures and classical music. We use PSD as a feature and SVM as a classifier. The average accuracies of subject-dependent model and subject-independent model are approximately 75.62% and 65.12%, respectively. Considering each pair of channels, temporal pair of channels (T7 and T8 gives a better result than the other area. Considering different frequency bands, high-frequency bands (Beta and Gamma give a better result than low-frequency bands. Considering different time durations for emotion elicitation, that result from 30 seconds does not have significant difference compared with the result from 60 seconds. From all of these results, we implement real-time EEG-based happiness detection system using only one pair of channels. Furthermore, we develop games based on the happiness detection system to help user recognize and control the happiness.

Manganese oxide phases and morphologies: A study on calcination temperature and atmospheric dependence

Directory of Open Access Journals (Sweden)

Matthias Augustin

2015-01-01

Full Text Available Manganese oxides are one of the most important groups of materials in energy storage science. In order to fully leverage their application potential, precise control of their properties such as particle size, surface area and Mnx+ oxidation state is required. Here, Mn3O4 and Mn5O8 nanoparticles as well as mesoporous α-Mn2O3 particles were synthesized by calcination of Mn(II glycolate nanoparticles obtained through an economical route based on a polyol synthesis. The preparation of the different manganese oxides via one route facilitates assigning actual structure–property relationships. The oxidation process related to the different MnOx species was observed by in situ X-ray diffraction (XRD measurements showing time- and temperature-dependent phase transformations occurring during oxidation of the Mn(II glycolate precursor to α-Mn2O3 via Mn3O4 and Mn5O8 in O2 atmosphere. Detailed structural and morphological investigations using transmission electron microscopy (TEM and powder XRD revealed the dependence of the lattice constants and particle sizes of the MnOx species on the calcination temperature and the presence of an oxidizing or neutral atmosphere. Furthermore, to demonstrate the application potential of the synthesized MnOx species, we studied their catalytic activity for the oxygen reduction reaction in aprotic media. Linear sweep voltammetry revealed the best performance for the mesoporous α-Mn2O3 species.

Photoluminescence and TEM evaluations of defects generated during SiGe-on-insulator virtual substrate fabrication: Temperature ramping process

International Nuclear Information System (INIS)

Wang, D.; Ii, S.; Ikeda, K.; Nakashima, H.; Matsumoto, K.; Nakamae, M.; Nakashima, H.

2006-01-01

Crystal qualities were evaluated by photoluminescence (PL) and transmission electron microscopy (TEM) for cap-Si/SiGe/Si-on-insulater (SOI) structure, which is the typical structure for SiGe-on-insulator virtual substrate fabrication using the Ge condensation by dry oxidation. The thicknesses of cap-Si, SOI and BOX layers are 10, 70, and 140 nm, respectively. We have three kinds of wafers with SiGe thicknesses of 74, 154 and 234 nm. All of the wafers were heated from 200 deg.C to a target temperature (T t ) in the range of 820-1200 deg. C with a ramping rate of 5 deg. C/min, and maintained at T t for 10 min. The air in the furnace was a mixture of O 2 and N 2 . The PL measurements were carried out using a 325 nm UV line of a continuous-wave HeCd laser. Free exciton peaks were clearly observed for the as-grown wafers and decreased with an increase in the annealing temperature. For the selected wafers, cross-sectional and plan-view TEM measurements show clear generation and variation of dislocations at the interface of SiGe/SOI according to the T t . Defect-related PL signals were observed at around 0.82, 0.88, 0.95 and 1.0 eV, which also varied according to the T t and the SiGe thickness. They were identified to dislocation-related and stacking-fault-related defects by TEM

Preparation of TEM specimen by cross-section technique

International Nuclear Information System (INIS)

Hamada, Shozo

1986-01-01

Transmission electron microscopy (TEM) is applied to the direct observation of the depth dependent damage structure in ion-irradiated stainless steel by using the cross-section technique; obtaining the TEM specimen from a slice of the irradiated stainless steel with thick Ni plating. Here has been developed the specimen preparation method of cross-section technique without heat treatment, which was necessary in the conventional method to strengthen the bonding between Ni and stainless steel. Nickel plating with good bonding to stainless steel is enabled by the following manner. First, the irradiated stainless steel is immersed in the Wood's nickel solution at room temperature for 60s to activate the surface, followed by the stricking for 300s at a current density of 300 A/m 2 in the solution to make fine and homogeneous nucleation of Ni on the stainless steel. Then, the sample is plated with Ni in the Watt's nickel plating solution at 333 K with current density of 900 ∼ 1,000 A/m 2 . The TEM disc is obtained by mechanical slicing from the specimen with Ni plating of more than 3 mm thickness. Electropolishing is accomplished by using both Ballmann method and jet electropolishing to perforate the disc accurately at the aimed point for the observation of the damage structure. (author)

DRAM selection and configuration for real-time mobile systems

NARCIS (Netherlands)

Gomony, M.D.; Weis, C.; Akesson, K.B.; Wehn, N.; Goossens, K.G.W.

2012-01-01

The performance and power consumption of mobile DRAMs (LPDDRs) depend on the configuration of system-level parameters, such as operating frequency, interface width, request size, and memory map. In mobile systems running both realtime and non-real-time applications, the memory configuration must

Temperature-dependent luminescence dynamics in ZnO nanorods

Energy Technology Data Exchange (ETDEWEB)

Priller, H. [Institut fuer Angewandte Physik, Universitaet Karlsruhe and Center for Functional Nanostructures (CFN), Wolfgang-Gaede-Str. 1, D-76131 Karlsruhe (Germany)]. E-mail: heiko.priller@physik.uni-karlsruhe.de; Hauschild, R. [Institut fuer Angewandte Physik, Universitaet Karlsruhe and Center for Functional Nanostructures (CFN), Wolfgang-Gaede-Str. 1, D-76131 Karlsruhe (Germany); Zeller, J. [Institut fuer Angewandte Physik, Universitaet Karlsruhe and Center for Functional Nanostructures (CFN), Wolfgang-Gaede-Str. 1, D-76131 Karlsruhe (Germany); Klingshirn, C. [Institut fuer Angewandte Physik, Universitaet Karlsruhe and Center for Functional Nanostructures (CFN), Wolfgang-Gaede-Str. 1, D-76131 Karlsruhe (Germany); Kalt, H. [Institut fuer Angewandte Physik, Universitaet Karlsruhe and Center for Functional Nanostructures (CFN), Wolfgang-Gaede-Str. 1, D-76131 Karlsruhe (Germany); Kling, R. [Abteilung Halbleiterphysik, Universitaet Ulm, Albert-Einstein Allee 45, 89081 Ulm (Germany); Reuss, F. [Abteilung Halbleiterphysik, Universitaet Ulm, Albert-Einstein Allee 45, 89081 Ulm (Germany); Kirchner, Ch. [Abteilung Halbleiterphysik, Universitaet Ulm, Albert-Einstein Allee 45, 89081 Ulm (Germany); Waag, A. [Institut fuer Halbleitertechnik, TU Braunschweig, Hans-Sommer-Str. 66, D-38106 Braunschweig (Germany)

2005-04-15

We report on an experimental study of the temporal photoluminescence dynamics of high-quality ZnO nanopillars from 10 K to room temperature. We find that defect states play an important role in the time evolution of the photoluminescence signal. At low excitation intensities capture into defects dominates the time dependence of the PL, at higher intensities they are saturated and the intrinsic excitation decay is observed. We separate the intrinsic exciton decay from the fast nonlinear M-band with the method of decay associated spectra and obtain the temperature dependence of the intrinsic exciton decay. High excitation measurements show a reduced exciton-exciton scattering in these thin nanorods.

Frequency and temperature dependence of ferromagnetic linewidth in exchange biased Permalloy

International Nuclear Information System (INIS)

Lubitz, P.; Rubinstein, M.; Krebs, J. J.; Cheng, S.-F.

2001-01-01

Ferromagnetic resonance linewidths were measured at 9.5 and 35 GHz and in the temperature range from 77 to 350 K for thin Permalloy (Py) films exchange biased by adjacent layers of NiO, CoO, or IrMn. Compared to unoxidized Py alone, for which the linewidth is nearly temperature independent in this range and scales linearly with frequency, exchange biased Py has broader lines with distinctive temperature dependences for each bias material at 9.5 GHz. Different temperature dependences were observed at 35 GHz. Our results are consistent with relaxation related to thermally driven reversal of the antiferromagnetic grains. Intrinsic damping and inhomogeneities also add to the widths. The qualitative features of the temperature and frequency dependences of the linewidths can be described with the usual expression for the slow relaxation linewidth mechanism. The temperature dependence of the relaxation time is taken from Neel's expression for the reversal time using appropriate rate prefactors and activation energies. [copyright] 2001 American Institute of Physics

Analysis and optimisation of heterogeneous real-time embedded systems

DEFF Research Database (Denmark)

Pop, Paul; Eles, Petru; Peng, Zebo

2005-01-01

. The success of such new design methods depends on the availability of analysis and optimisation techniques. Analysis and optimisation techniques for heterogeneous real-time embedded systems are presented in the paper. The authors address in more detail a particular class of such systems called multi...... of application messages to frames. Optimisation heuristics for frame packing aimed at producing a schedulable system are presented. Extensive experiments and a real-life example show the efficiency of the frame-packing approach....

Analysis and optimisation of heterogeneous real-time embedded systems

DEFF Research Database (Denmark)

Pop, Paul; Eles, Petru; Peng, Zebo

2006-01-01

. The success of such new design methods depends on the availability of analysis and optimisation techniques. Analysis and optimisation techniques for heterogeneous real-time embedded systems are presented in the paper. The authors address in more detail a particular class of such systems called multi...... of application messages to frames. Optimisation heuristics for frame packing aimed at producing a schedulable system are presented. Extensive experiments and a real-life example show the efficiency of the frame-packing approach....

Analysis and Optimization of Heterogeneous Real-Time Embedded Systems

DEFF Research Database (Denmark)

Pop, Paul; Eles, Petru; Peng, Zebo

2005-01-01

. The success of such new design methods depends on the availability of analysis and optimization techniques. In this paper, we present analysis and optimization techniques for heterogeneous real-time embedded systems. We address in more detail a particular class of such systems called multi-clusters, composed...... to frames. Optimization heuristics for frame packing aiming at producing a schedulable system are presented. Extensive experiments and a real-life example show the efficiency of the frame-packing approach....

Time-temperature superposition in viscous liquids

DEFF Research Database (Denmark)

Olsen, Niels Boye; Dyre, Jeppe; Christensen, Tage Emil

2001-01-01

with a reduced time definition based on a recently proposed expression for the relaxation time, where G [infinity] reflects the fictive temperature. All parameters entering the reduced time were determined from independent measurements of the frequency-dependent shear modulus of the equilibrium liquid....

Real-Time Climate Simulations in the Interactive 3D Game Universe Sandbox ²

Science.gov (United States)

Goldenson, N. L.

2014-12-01

Exploration in an open-ended computer game is an engaging way to explore climate and climate change. Everyone can explore physical models with real-time visualization in the educational simulator Universe Sandbox ² (universesandbox.com/2), which includes basic climate simulations on planets. I have implemented a time-dependent, one-dimensional meridional heat transport energy balance model to run and be adjustable in real time in the midst of a larger simulated system. Universe Sandbox ² is based on the original game - at its core a gravity simulator - with other new physically-based content for stellar evolution, and handling collisions between bodies. Existing users are mostly science enthusiasts in informal settings. We believe that this is the first climate simulation to be implemented in a professionally developed computer game with modern 3D graphical output in real time. The type of simple climate model we've adopted helps us depict the seasonal cycle and the more drastic changes that come from changing the orbit or other external forcings. Users can alter the climate as the simulation is running by altering the star(s) in the simulation, dragging to change orbits and obliquity, adjusting the climate simulation parameters directly or changing other properties like CO2 concentration that affect the model parameters in representative ways. Ongoing visuals of the expansion and contraction of sea ice and snow-cover respond to the temperature calculations, and make it accessible to explore a variety of scenarios and intuitive to understand the output. Variables like temperature can also be graphed in real time. We balance computational constraints with the ability to capture the physical phenomena we wish to visualize, giving everyone access to a simple open-ended meridional energy balance climate simulation to explore and experiment with. The software lends itself to labs at a variety of levels about climate concepts including seasons, the Greenhouse effect

Visualization of swallowing using real-time TrueFISP MR fluoroscopy

Energy Technology Data Exchange (ETDEWEB)

Barkhausen, Joerg; Goyen, Mathias; Lauenstein, Thomas; Debatin, Joerg F. [Department of Diagnostic Radiology, University Hospital Essen (Germany); Winterfeld, F. von; Arweiler-Harbeck, Diana [Department of Otorhinolaryngology, University Hospital Essen (Germany)

2002-01-01

The aim of this study was to evaluate the ability of different real-time true fast imaging with steady precession (TrueFISP) sequences regarding their ability to depict the swallowing process and delineate oropharyngeal pathologies in patients with dysphagia. Real-time TrueFISP visualization of swallowing was performed in 8 volunteers and 6 patients with dysphagia using a 1.5 T scanner (Magnetom Sonata, Siemens, Erlangen Germany) equipped with high-performance gradients (amplitude 40 mT/m). Image quality of four different real-time TrueFISP sequences (TR 2.2-3.0 ms, TE 1.1-1.5 ms, matrix 63 x 128-135 x 256, field of view 250 mm{sup 2}, acquisition time per image 139-405 ms) was evaluated. Water, yoghurt, and semolina pudding were assessed as oral contrast agents. Functional exploration of the oropharyngeal apparatus was best possible using the fastest real-time TrueFISP sequence (TR 2.2 ms, TE 1.1 ms, matrix 63 x 128). Increased acquisition time resulted in blurring of anatomical structures. As the image contrast of TrueFISP sequences depends on T2/T1 properties, all tested foodstuff were well suited as oral contrast agents, but image quality was best using semolina pudding. Real-time visualization of swallowing is possible using real-time TrueFISP sequences in conjunction with oral contrast agents. For the functional exploration of swallowing high temporal resolution is more crucial than spatial resolution. (orig.)

Friction coefficient of skin in real-time.

Science.gov (United States)

Sivamani, Raja K; Goodman, Jack; Gitis, Norm V; Maibach, Howard I

2003-08-01

Friction studies are useful in quantitatively investigating the skin surface. Previous studies utilized different apparatuses and materials for these investigations but there was no real-time test parameter control or monitoring. Our studies incorporated the commercially available UMT Series Micro-Tribometer, a tribology instrument that permits real-time monitoring and calculation of the important parameters in friction studies, increasing the accuracy over previous tribology and friction measurement devices used on skin. Our friction tests were performed on four healthy volunteers and on abdominal skin samples. A stainless steel ball was pressed on to the skin with at a pre-set load and then moved across the skin at a constant velocity of 5 mm/min. The UMT continuously monitored the friction force of the skin and the normal force of the ball to calculate the friction coefficient in real-time. Tests investigated the applicability of Amonton's law, the impact of increased and decreased hydration, and the effect of the application of moisturizers. The friction coefficient depends on the normal load applied, and Amonton's law does not provide an accurate description for the skin surface. Application of water to the skin increased the friction coefficient and application of isopropyl alcohol decreased it. Fast acting moisturizers immediately increased the friction coefficient, but did not have the prolonged effect of the slow, long lasting moisturizers. The UMT is capable of making real-time measurements on the skin and can be used as an effective tool to study friction properties. Results from the UMT measurements agree closely with theory regarding the skin surface.

Attainable conditions and exact invariant for the time-dependent harmonic oscillator

Energy Technology Data Exchange (ETDEWEB)

Guasti, Manuel Fernandez [Lab. de Optica Cuantica, Dep. de Fisica, Universidad A. Metropolitana, Unidad Iztapalapa, Mexico DF, Ap. Post. 55-534 (Mexico)

2006-09-22

The time-dependent oscillator equation is solved numerically for various trajectories in amplitude and phase variables. The solutions exhibit a finite time-dependent parameter whenever the squared amplitude times the derivative of the phase is invariant. If the invariant relationship does not hold, the time-dependent parameter has divergent singularities. These observations lead to the proposition that the harmonic oscillator equation with finite time-dependent parameter must have amplitude and phase solutions fulfilling the invariant relationship. Since the time-dependent parameter or the potential must be finite for any real oscillator implementation, the invariant must hold for any such physically realizable system.

Attainable conditions and exact invariant for the time-dependent harmonic oscillator

International Nuclear Information System (INIS)

Guasti, Manuel Fernandez

2006-01-01

The time-dependent oscillator equation is solved numerically for various trajectories in amplitude and phase variables. The solutions exhibit a finite time-dependent parameter whenever the squared amplitude times the derivative of the phase is invariant. If the invariant relationship does not hold, the time-dependent parameter has divergent singularities. These observations lead to the proposition that the harmonic oscillator equation with finite time-dependent parameter must have amplitude and phase solutions fulfilling the invariant relationship. Since the time-dependent parameter or the potential must be finite for any real oscillator implementation, the invariant must hold for any such physically realizable system

Characterizing time-dependent mechanics in metallic MEMS

Directory of Open Access Journals (Sweden)

Geers M.G.D.

2010-06-01

Full Text Available Experiments for characterization of time-dependent material properties in free-standing metallic microelectromechanical system (MEMS pose challenges: e.g. fabrication and handling (sub-μm sized specimens, control and measurement of sub-μN loads and sub-μm displacements over long periods and various temperatures [1]. A variety of experimental setups have been reported each having their pros and cons. One example is a micro-tensile tester with an ingenious electro-static specimen gripping system [2] aiding simple specimen design giving good results at μN and sub-μm levels, but without in-situ full-field observations. Other progressive examples assimilate the specimen, MEMS actuators and load cells on a single chip [3,4] yielding significant results at nN and nm levels with in-situ TEM/SEM observability, though not without complications: complex load actuator/sensor calibration per chip, measures to reduce fabrication failure and unfeasible cofabrication on wafers with commercial metallic MEMS. This work aims to overcome these drawbacks by developing experimental methods with high sensitivity, precision and in-situ full-field observation capabilities. Moreover, these should be applicable to simple free-standing metallic MEMS that can be co-fabricated with commercial devices. These methods will then serve in systematic studies into size-effects in time-dependent material properties. First a numeric-experimental method is developed. It characterizes bending deformation of onwafer μm-sized aluminum cantilevers. A specially designed micro-clamp is used to mechanically apply a constant precise deflection of the beam (zres <50 nm for a prolonged period, see fig. 1. After this period, the deflection by the micro-clamp is removed. Full-field height maps with the ensuing deformation are measured over time with confocal optical profilometry (COP. This yields the tip deflection as function of time with ~3 nm precision, see fig.2. To extract material

Real-time Kalman filter: Cooling of an optically levitated nanoparticle

Science.gov (United States)

Setter, Ashley; Toroš, Marko; Ralph, Jason F.; Ulbricht, Hendrik

2018-03-01

We demonstrate that a Kalman filter applied to estimate the position of an optically levitated nanoparticle, and operated in real-time within a field programmable gate array, is sufficient to perform closed-loop parametric feedback cooling of the center-of-mass motion to sub-Kelvin temperatures. The translational center-of-mass motion along the optical axis of the trapped nanoparticle has been cooled by 3 orders of magnitude, from a temperature of 300 K to a temperature of 162 ±15 mK.

Real-time Kalman filter: cooling of an optically levitated nanoparticle

OpenAIRE

Setter, Ashley; Toros, Marko; Ralph, Jason; Ulbricht, Hendrik

2018-01-01

We demonstrate that a Kalman filter applied to estimate the position of an optically levitated nanoparticle, and operated in real-time within a Field Programmable Gate Array (FPGA), is sufficient to perform closed-loop parametric feedback cooling of the centre of mass motion to sub-Kelvin temperatures. The translational centre of mass motion along the optical axis of the trapped nanoparticle has been cooled by three orders of magnitude, from a temperature of 300K to a temperature of 162 +/- 1...

Tem holder for sample transfer under reaction conditions

DEFF Research Database (Denmark)

Damsgaard, Christian Danvad; Zandbergen, Henny W.; Wagner, Jakob Birkedal

Environmental transmission electron microscopy (ETEM) studies are usually performed using conventional sample holders in a dedicated ETEM [1] or in a traditional TEM by use of a dedicated high-pressure cell sample holder [2]. In both cases, the setup defines the conditions regarding gas, pressure......]. Furthermore, dedicated transfer holders have been used to transfer catalyst samples between reactor set-ups and TEM at room temperature in inert atmosphere [5]. To take the full advantage of complementary in situ techniques, transfer under reactions conditions is essential. This study introduces the in situ...... transfer concept by use of a dedicated TEM transfer holder capable of enclosing the sample in a gaseous environment at temperatures up to approx. 900C. By oxidation and reduction experiments of Cu nanoparticles it is shown possible to keep the reaction conditions during transfer outside the microscope...

A Real-Time Simulink Interfaced Fast-Charging Methodology of Lithium-Ion Batteries under Temperature Feedback with Fuzzy Logic Control

Directory of Open Access Journals (Sweden)

Muhammad Umair Ali

2018-05-01

Full Text Available The lithium-ion battery has high energy and power density, long life cycle, low toxicity, low discharge rate, more reliability, and better efficiency compared to other batteries. On the other hand, the issue of a reduction in charging time of the lithium-ion battery is still a bottleneck for the commercialization of electric vehicles (EVs. Therefore, an approach to charge lithium-ion batteries at a faster rate is needed. This paper proposes an efficient, real-time, fast-charging methodology of lithium-ion batteries. Fuzzy logic was adopted to drive the charging current trajectory. A temperature control unit was also implemented to evade the effects of fast charging on the aging mechanism. The proposed method of charging also protects the battery from overvoltage and overheating. Extensive testing and comprehensive analysis were conducted to examine the proposed charging technique. The results show that the proposed charging strategy favors a full battery recharging in 9.76% less time than the conventional constant-current–constant-voltage (CC/CV method. The strategy charges the battery at a 99.26% state of charge (SOC without significant degradation. The entire scheme was implemented in real time, using Arduino interfaced with MATLABTM Simulink. This decrease in charging time assists in the fast charging of cell phones and notebooks and in the large-scale deployment of EVs.

Real-time control of internal transport barriers in JET

Energy Technology Data Exchange (ETDEWEB)

Mazon, D.; Litaudon, X.; Moreau, D. [Association Euratom-CEA, CEA Cadarache, St. Paul lez Durance (France)] [and others

2002-07-01

We present the results of recent experiments related to real-time control of internal transport barriers (ITBs) in JET. Using a simple criterion to characterize the ITB existence, location and strength, we have successfully controlled for the first time the radial electron temperature profile within the ITB. The dimensionless variable used in the real-time algorithm - ratio of the ion gyro-radius to the local gradient scale length of the electron temperature - is a measure of the normalized electron temperature gradient and characterizes satisfactorily the main ITB features with a relatively low computational cost. We show several examples of control of this variable in various experimental conditions of toroidal field and plasma current, using different heating systems as control actuators. We also present a double-loop feedback scheme where both the global neutron rate from D-D reactions and the ITB strength are controlled simultaneously. In this case the ITB is sustained in a fully non-inductive current drive regime during several seconds. With the proposed control method, disruptions are avoided by holding the plasma performance at a prescribed target and this opens the route towards stationary operation of tokamak plasmas with ITBs. Initial results suggest that the additional control of the current profile is an important issue for achieving steady-state operation, in particular in the triggering and the sustainment of the ITB. (author)

Time-dependent fracture of materials at elevated temperature for solar thermal power systems

International Nuclear Information System (INIS)

Gupta, G.D.

1979-01-01

Various Solar Thermal Power Systems are briefly described. The components of solar power systems in which time-dependent fracture problems become important are identified. Typical materials of interest, temperature ranges, and stress states are developed; and the number of cycles during the design life of these systems are indicated. The ASME Code procedures used by designers to predict the life of these components are briefly described. Some of the major problems associated with the use of these ASME procedures in the design of solar components are indicated. Finally, a number of test and development needs are identified which would enable the designers to predict the life of the solar power system components with a reasonable degree of confidence

Integrated Equivalent Circuit and Thermal Model for Simulation of Temperature-Dependent LiFePO4 Battery in Actual Embedded Application

Directory of Open Access Journals (Sweden)

Zuchang Gao

2017-01-01

Full Text Available A computational efficient battery pack model with thermal consideration is essential for simulation prototyping before real-time embedded implementation. The proposed model provides a coupled equivalent circuit and convective thermal model to determine the state-of-charge (SOC and temperature of the LiFePO4 battery working in a real environment. A cell balancing strategy applied to the proposed temperature-dependent battery model balanced the SOC of each cell to increase the lifespan of the battery. The simulation outputs are validated by a set of independent experimental data at a different temperature to ensure the model validity and reliability. The results show a root mean square (RMS error of 1.5609 × 10−5 for the terminal voltage and the comparison between the simulation and experiment at various temperatures (from 5 °C to 45 °C shows a maximum RMS error of 7.2078 × 10−5.

Thermal Imaging Systems for Real-Time Applications in Smart Cities

DEFF Research Database (Denmark)

Gade, Rikke; Moeslund, Thomas B.; Nielsen, Søren Zebitz

2016-01-01

of thermal imaging in real-time Smart City applications. Thermal cameras operate independently of light and measure the radiated infrared waves representing the temperature of the scene. In order to showcase the possibilities, we present five different applications which use thermal imaging only...

Real-Time Tropospheric Delay Estimation using IGS Products

Science.gov (United States)

Stürze, Andrea; Liu, Sha; Söhne, Wolfgang

2014-05-01

The Federal Agency for Cartography and Geodesy (BKG) routinely provides zenith tropospheric delay (ZTD) parameter for the assimilation in numerical weather models since more than 10 years. Up to now the results flowing into the EUREF Permanent Network (EPN) or E-GVAP (EUMETNET EIG GNSS water vapour programme) analysis are based on batch processing of GPS+GLONASS observations in differential network mode. For the recently started COST Action ES1206 about "Advanced Global Navigation Satellite Systems tropospheric products for monitoring severe weather events and climate" (GNSS4SWEC), however, rapid updates in the analysis of the atmospheric state for nowcasting applications require changing the processing strategy towards real-time. In the RTCM SC104 (Radio Technical Commission for Maritime Services, Special Committee 104) a format combining the advantages of Precise Point Positioning (PPP) and Real-Time Kinematic (RTK) is under development. The so-called State Space Representation approach is defining corrections, which will be transferred in real-time to the user e.g. via NTRIP (Network Transport of RTCM via Internet Protocol). Meanwhile messages for precise orbits, satellite clocks and code biases compatible to the basic PPP mode using IGS products are defined. Consequently, the IGS Real-Time Service (RTS) was launched in 2013 in order to extend the well-known precise orbit and clock products by a real-time component. Further messages e.g. with respect to ionosphere or phase biases are foreseen. Depending on the level of refinement, so different accuracies up to the RTK level shall be reachable. In co-operation of BKG and the Technical University of Darmstadt the real-time software GEMon (GREF EUREF Monitoring) is under development. GEMon is able to process GPS and GLONASS observation and RTS product data streams in PPP mode. Furthermore, several state-of-the-art troposphere models, for example based on numerical weather prediction data, are implemented. Hence, it

Sphalerons and instantons at finite temperature

International Nuclear Information System (INIS)

Aoyama, H.; Goldberg, H.; Ryzak, Z.

1988-01-01

A variational Ansatz for a solution of the Euclidean time-dependent Weinberg-Salam field equations which connects topologically distinct vacua is presented. The Ansatz allows a unified description of real-time transitions involving baryon-number nonconservation from the zero-temperature (instanton) limit up to the electroweak transition temperature

Development of a Photovoltaic Array Emulator System in Real Time Considering Climatic Conditions Variations

Directory of Open Access Journals (Sweden)

Camilo E. Ardila-Franco

2013-11-01

Full Text Available This paper presents the development of an emulator that has the ability to replicate, in real time, the behavior of photovoltaic panels (PV arrays considering different conditions of irradiation and temperature for each one. The emulator consists of a data acquisition card, a programmable source and a computer. It is based on the bypass diode model that provides a better approximation to real operating conditions. The solution is computed by a simplified equation that uses the Lambert W function, which reduces the computation time. After that, it generates a solution table of values of current as a function of voltage on terminals, temperature and irradiation. Real-time emulation is performed by means of a search algorithm in the solutions table of the closest value to the voltage imposed on the terminals.

Development of a Capacitive Ice Sensor to Measure Ice Growth in Real Time

Directory of Open Access Journals (Sweden)

Xiang Zhi

2015-03-01

Full Text Available This paper presents the development of the capacitive sensor to measure the growth of ice on a fuel pipe surface in real time. The ice sensor consists of pairs of electrodes to detect the change in capacitance and a thermocouple temperature sensor to examine the ice formation situation. In addition, an environmental chamber was specially designed to control the humidity and temperature to simulate the ice formation conditions. From the humidity, a water film is formed on the ice sensor, which results in an increase in capacitance. Ice nucleation occurs, followed by the rapid formation of frost ice that decreases the capacitance suddenly. The capacitance is saturated. The developed ice sensor explains the ice growth providing information about the icing temperature in real time.

Development of a capacitive ice sensor to measure ice growth in real time.

Science.gov (United States)

Zhi, Xiang; Cho, Hyo Chang; Wang, Bo; Ahn, Cheol Hee; Moon, Hyeong Soon; Go, Jeung Sang

2015-03-19

This paper presents the development of the capacitive sensor to measure the growth of ice on a fuel pipe surface in real time. The ice sensor consists of pairs of electrodes to detect the change in capacitance and a thermocouple temperature sensor to examine the ice formation situation. In addition, an environmental chamber was specially designed to control the humidity and temperature to simulate the ice formation conditions. From the humidity, a water film is formed on the ice sensor, which results in an increase in capacitance. Ice nucleation occurs, followed by the rapid formation of frost ice that decreases the capacitance suddenly. The capacitance is saturated. The developed ice sensor explains the ice growth providing information about the icing temperature in real time.

In vivo real-time rectal wall dosimetry for prostate radiotherapy

International Nuclear Information System (INIS)

Hardcastle, Nicholas; Cutajar, Dean L; Metcalfe, Peter E; Lerch, Michael L F; Tome, Wolfgang A; Rosenfeld, Anatoly B; Perevertaylo, Vladimir L

2010-01-01

Rectal balloons are used in external beam prostate radiotherapy to provide reproducible anatomy and rectal dose reductions. This is an investigation into the combination of a MOSFET radiation detector with a rectal balloon for real-time in vivo rectal wall dosimetry. The MOSFET used in the study is a radiation detector that provides a water equivalent depth of measurement of 70 μm. Two MOSFETs were combined in a face-to-face orientation. The reproducibility, sensitivity and angular dependence were measured for the dual MOSFET in a 6 MV photon beam. The dual MOSFET was combined with a rectal balloon and irradiated with hypothetical prostate treatments in a phantom. The anterior rectal wall dose was measured in real time and compared with the planning system calculated dose. The dual MOSFET showed angular dependence within ±2.5% in the azimuth and +2.5%/-4% in the polar axes. When compared with an ion chamber measurement in a phantom, the dual MOSFET agreed within 2.5% for a range of radiation path lengths and incident angles. The dual MOSFET had reproducible sensitivity for fraction sizes of 2-10 Gy. For the hypothetical prostate treatments the measured anterior rectal wall dose was 2.6 and 3.2% lower than the calculated dose for 3DCRT and IMRT plans. This was expected due to limitations of the dose calculation method used at the balloon cavity interface. A dual MOSFET combined with a commercial rectal balloon was shown to provide reproducible measurements of the anterior rectal wall dose in real time. The measured anterior rectal wall dose agreed with the expected dose from the treatment plan for 3DCRT and IMRT plans. The dual MOSFET could be read out in real time during the irradiation, providing the capability for real-time dose monitoring of the rectal wall dose during treatment.

A real-time architecture for time-aware agents.

Science.gov (United States)

Prouskas, Konstantinos-Vassileios; Pitt, Jeremy V

2004-06-01

This paper describes the specification and implementation of a new three-layer time-aware agent architecture. This architecture is designed for applications and environments where societies of humans and agents play equally active roles, but interact and operate in completely different time frames. The architecture consists of three layers: the April real-time run-time (ART) layer, the time aware layer (TAL), and the application agents layer (AAL). The ART layer forms the underlying real-time agent platform. An original online, real-time, dynamic priority-based scheduling algorithm is described for scheduling the computation time of agent processes, and it is shown that the algorithm's O(n) complexity and scalable performance are sufficient for application in real-time domains. The TAL layer forms an abstraction layer through which human and agent interactions are temporally unified, that is, handled in a common way irrespective of their temporal representation and scale. A novel O(n2) interaction scheduling algorithm is described for predicting and guaranteeing interactions' initiation and completion times. The time-aware predicting component of a workflow management system is also presented as an instance of the AAL layer. The described time-aware architecture addresses two key challenges in enabling agents to be effectively configured and applied in environments where humans and agents play equally active roles. It provides flexibility and adaptability in its real-time mechanisms while placing them under direct agent control, and it temporally unifies human and agent interactions.

A Structural Study of Escherichia coli Cells Using an In Situ Liquid Chamber TEM Technology

Directory of Open Access Journals (Sweden)

Yibing Wang

2015-01-01

Full Text Available Studying cell microstructures and their behaviors under living conditions has been a challenging subject in microbiology. In this work, in situ liquid chamber TEM was used to study structures of Escherichia coli cells in aqueous solutions at a nanometer-scale resolution. Most of the cells remained intact under electron beam irradiation, and nanoscale structures were observed during the TEM imaging. The analysis revealed structures of pili surrounding the E. coli cells; the movements of the pili in the liquid were also observed during the in situ tests. This technology also allowed the observation of features of the nucleoid in the E. coli cells. Overall, in situ TEM can be applied as a valuable tool to study real-time microscopic structures and processes in microbial cells residing in native aqueous solutions.

Architecture for dynamically reconfigurable real-time lossless compression

Science.gov (United States)

Carter, Alison J.; Audsley, Neil C.

2004-05-01

Image compression is a computationally intensive task, which can be undertaken most efficiently by dedicated hardware. If a portable device is to carry out real-time compression on a variety of image types, then it may be useful to reconfigure the circuitry dynamically. Using commercial off-the shelf (COTS) chips, reconfiguration is usually implemented by a complete re-load from memory, but it is also possible to perform a partial reconfiguration. This work studies the use of programmable hardware devices to implement the lossless JPEG compression algorithm in real-time on a stream of independent image frames. The data rate is faster than can be compressed serially in hardware by a single processor, so the operation is split amongst several processors. These are implemented as programmable circuits, together with necessary buffering of input and output data. The timing of input and output, bearing in mind the different, and context-dependent amounts of data due to Huffman coding, is analyzed using storage-timing graphs. Because there may be differing parameters from one frame to the next, several different configurations are prepared and stored, ready to load as required. The scheduling of these reconfigurations, and the distribution/recombination of data streams is studied, giving an analysis of the real-time performance.

Water state and TEM analysis of Konjac irradiation copolymer

International Nuclear Information System (INIS)

Geng Shengrong; Xia Hezhou; Chen Xueling; Ye Lixiu; Hua Yuejin

2012-01-01

To study the absorption performance of Konjac-AA copolymer prepared by irradiation, the water absorbent capacity, sorbent speed and water keeping ability was determined and DSC and TEM analysis were used to explore the water content and structure characters. The results showed that on room temperature the largest water absorption speed was 16 g · g -1 · min -1 at, and the largest water absorption was 400 times at 60 min. The water absorption was affected by granularity, temperature, ion content and ion type, especially the ion type, the water keeping ability was affected by temperature and time, which was up to 35% while the fully water absorbed copolymer was kept under room temperature for 15 d. The free and bounder water content which was assimilated by the plants was 99.617%. The gel stale co polymer has a three-dimensional structure of spiral, which was constituted by spherical objects of varying sizes. (authors)

Towards Real-Time Argumentation

Directory of Open Access Journals (Sweden)

Vicente JULIÁN

2016-07-01

Full Text Available In this paper, we deal with the problem of real-time coordination with the more general approach of reaching real-time agreements in MAS. Concretely, this work proposes a real-time argumentation framework in an attempt to provide agents with the ability of engaging in argumentative dialogues and come with a solution for their underlying agreement process within a bounded period of time. The framework has been implemented and evaluated in the domain of a customer support application. Concretely, we consider a society of agents that act on behalf of a group of technicians that must solve problems in a Technology Management Centre (TMC within a bounded time. This centre controls every process implicated in the provision of technological and customer support services to private or public organisations by means of a call centre. The contract signed between the TCM and the customer establishes penalties if the specified time is exceeded.

(Alpha-) quenching temperature dependence in liquid scintillator

Energy Technology Data Exchange (ETDEWEB)

Soerensen, Arnd; Lozza, Valentina; Krosigk, Belina von; Zuber, Kai [Institut fuer Kern- und Teilchenphysik, TU Dresden (Germany)

2015-07-01

Liquid scintillator (LS) is an effective and promising detector material, which is and will be used by many small and large scale experiments. In order to perform correct signal identification and background suppression, a very good knowledge of LS properties is crucial. One of those is the light yield from alpha particles in liquid scintillator. This light output strongly quenched, approx. 10 times compared to that of electrons, and has been precisely studied at room temperature for various LS. Big scintillator experiments, such as SNO+ and maybe future large scale detectors, will operate at different temperatures. While a strong temperature dependence is well known for solid state scintillators, due to the different scintillation process, a quenching temperature dependence in LS is usually assumed negligible. On the other hand, inconsistencies in between measurements are often explained by potential temperature effects. This study investigates LAB based liquid scintillator with an intrinsic, dissolved alpha emitter and its behaviour with temperature change. In a small, cooled and heated setup, a stabilized read-out with two PMTs is realised. First results are presented.

Formal Specification and Verification of Real-Time Multi-Agent Systems using Timed-Arc Petri Nets

Directory of Open Access Journals (Sweden)

QASIM, A.

2015-08-01

Full Text Available In this study we have formally specified and verified the actions of communicating real-time software agents (RTAgents. Software agents are expected to work autonomously and deal with unfamiliar situations astutely. Achieving cent percent test cases coverage for these agents has always been a problem due to limited resources. Also a high degree of dependability and predictability is expected from real-time software agents. In this research we have used Timed-Arc Petri Net's for formal specification and verification. Formal specification of e-agents has been done in the past using Linear Temporal Logic (LTL but we believe that Timed-Arc Petri Net's being more visually expressive provides a richer framework for such formalism. A case study of Stock Market System (SMS based on Real Time Multi Agent System framework (RTMAS using Timed-Arc Petri Net's is taken to illustrate the proposed modeling approach. The model was verified used AF, AG, EG, and EF fragments of Timed Computational Tree Logic (TCTL via translations to timed automata.

The JET real-time plasma-wall load monitoring system

International Nuclear Information System (INIS)

Valcárcel, D.F.; Alves, D.; Card, P.; Carvalho, B.B.; Devaux, S.; Felton, R.; Goodyear, A.; Lomas, P.J.; Maviglia, F.; McCullen, P.; Reux, C.; Rimini, F.; Stephen, A.; Zabeo, L.

2014-01-01

Highlights: • The paper describes the JET real-time system monitoring the first-wall plasma loads. • It presents the motivation, physics basis, design and implementation of the system. • It also presents the integration in the JET CODAS. • Operational results are presented. - Abstract: In the past, the Joint European Torus (JET) has operated with a first-wall composed of Carbon Fibre Composite (CFC) tiles. The thermal properties of the wall were monitored in real-time during plasma operations by the WALLS system. This software routinely performed model-based thermal calculations of the divertor and Inner Wall Guard Limiter (IWGL) tiles calculating bulk temperatures and strike-point positions as well as raising alarms when these were beyond operational limits. Operation with the new ITER-like wall presents a whole new set of challenges regarding machine protection. One example relates to the new beryllium limiter tiles with a melting point of 1278 °C, which can be achieved during a plasma discharge well before the bulk temperature rises to this value. This requires new and accurate power deposition and thermal diffusion models. New systems were deployed for safe operation with the new wall: the Real-time Protection Sequencer (RTPS) and the Vessel Thermal Map (VTM). The former allows for a coordinated stop of the pulse and the latter uses the surface temperature map, measured by infra-red (IR) cameras, to raise alarms in case of hot-spots. Integration of WALLS with these systems is required as RTPS responds to raised alarms and VTM, the primary protection system for the ITER-like wall, can use WALLS as a vessel temperature provider. This paper presents the engineering design, implementation and results of WALLS towards D-T operation, where it will act as a primary protection system when the IR cameras are blinded by the fusion reaction neutrons. The first operational results, with emphasis on its performance, are also presented

The JET real-time plasma-wall load monitoring system

Energy Technology Data Exchange (ETDEWEB)

Valcárcel, D.F., E-mail: daniel.valcarcel@ipfn.ist.utl.pt [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, P-1049-001 Lisboa (Portugal); Alves, D. [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, P-1049-001 Lisboa (Portugal); Card, P. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Carvalho, B.B. [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa, P-1049-001 Lisboa (Portugal); Devaux, S. [Max-Planck-Institut für Plasmaphysik, EURATOM-Assoziation, D-85748 Garching (Germany); Felton, R.; Goodyear, A.; Lomas, P.J. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Maviglia, F. [Associazione EURATOM-ENEA-CREATE, Univ. di Napoli Federico II, Via Claudio 21, 80125 Napoli (Italy); McCullen, P. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Reux, C. [Ecole Polytechnique, LPP, CNRS UMR 7648, 91128 Palaiseau (France); Rimini, F.; Stephen, A. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Zabeo, L. [ITER Organization, Route de Vinon sur Verdon, 13115 St., Paul Lez Durance (France); and others

2014-03-15

Highlights: • The paper describes the JET real-time system monitoring the first-wall plasma loads. • It presents the motivation, physics basis, design and implementation of the system. • It also presents the integration in the JET CODAS. • Operational results are presented. - Abstract: In the past, the Joint European Torus (JET) has operated with a first-wall composed of Carbon Fibre Composite (CFC) tiles. The thermal properties of the wall were monitored in real-time during plasma operations by the WALLS system. This software routinely performed model-based thermal calculations of the divertor and Inner Wall Guard Limiter (IWGL) tiles calculating bulk temperatures and strike-point positions as well as raising alarms when these were beyond operational limits. Operation with the new ITER-like wall presents a whole new set of challenges regarding machine protection. One example relates to the new beryllium limiter tiles with a melting point of 1278 °C, which can be achieved during a plasma discharge well before the bulk temperature rises to this value. This requires new and accurate power deposition and thermal diffusion models. New systems were deployed for safe operation with the new wall: the Real-time Protection Sequencer (RTPS) and the Vessel Thermal Map (VTM). The former allows for a coordinated stop of the pulse and the latter uses the surface temperature map, measured by infra-red (IR) cameras, to raise alarms in case of hot-spots. Integration of WALLS with these systems is required as RTPS responds to raised alarms and VTM, the primary protection system for the ITER-like wall, can use WALLS as a vessel temperature provider. This paper presents the engineering design, implementation and results of WALLS towards D-T operation, where it will act as a primary protection system when the IR cameras are blinded by the fusion reaction neutrons. The first operational results, with emphasis on its performance, are also presented.

Moessbauer effect and TEM in mineralogy

International Nuclear Information System (INIS)

Ferrow, E.A.

1994-01-01

Moessbauer effect (ME) provides useful information on oxidation state, co-ordination number, co-ordination state, site occupancies, and magnetic properties of Fe-bearing phases. The information gained by ME together with the information provided by other conventional techniques is used to extract temperature, pressure, and kinetics of rock-forming processes. Nevertheless, ME requires that the phases studied are homogeneous over an extremely large volume and that Fe is a major component of the system. Transmission electron microscopy (TEM), on the other hand, provides similar information over a very small volume for a system of any component. However, present TEM spectrometers do not provide sufficient resolution to detect the mixed oxidation state. A complete characterisation of phases in rocks requires, therefore, that conventional techniques be combined with TEM. (orig.)

Investigations of oxide particles in unirradiated ODS-Eurofer by TEM and 3D atom probe methods

International Nuclear Information System (INIS)

Aleev, A.A.; Iskandarov, N.A.; Nikitin, A.A.; Rogizhkin, S.V.; Zaluzhny, A.G.; Klimenkov, M.; Lindau, R.; Moeslang, A.; Vladimirov, P.

2009-01-01

Oxide dispersion strengthened steels possess better high-temperature creep and radiation resistance than conventionally produced ferritic/martensitic steels. This behavior is mainly caused by the presence of highly dispersed and extremely stable oxide particles with sizes of few nanometers. One of the promising oxides used for dispersion strengthening was yttria (Y 2 O 3 ), which was introduced into EUROFER by mechanical alloying followed by the hot isostatic pressing at temperature around 1000-1200 dg. C and pressure ∼100 MPa. It was found that mechanical properties were strongly depended on size and spatial distribution of the precipitates. Therefore considerable efforts are focused on the investigation of the chemical composition and orientation of precipitates with respect to the steel matrix. Recent studies of Eurofer ODS steel (9%-CrWVTa) by SANS revealed the presence of high number density structural features with a size of approximately one nanometer. At the same time, previous studies by TEM identified only high number of small (6-40 nm) Y 2 O 3 particles. In this work we tried to get a deeper inside into the nanostructure of this material by means of tomographic atom probe and to correlate the results with the picture obtained by TEM. The present investigations revealed fine (∼2 nm) enrichments containing not only yttrium and oxygen but also vanadium and nitrogen. Concentration of vanadium was found to be approximately at the same level as yttrium. Some of the enrichments contained only three or even two elements mentioned above. Estimated number density of enrichments is about (1/5) x 10 23 m -3 . We suppose that these enriched zones might be precursors of the larger precipitates observed by TEM. The thesis seems to be supported by the similarities of the chemical composition and spatial distribution of elements inside enriched zones and nano precipitates studied by atomic probe and analytical TEM methods. (author)

Real-time PCR in virology.

Science.gov (United States)

Mackay, Ian M; Arden, Katherine E; Nitsche, Andreas

2002-03-15

The use of the polymerase chain reaction (PCR) in molecular diagnostics has increased to the point where it is now accepted as the gold standard for detecting nucleic acids from a number of origins and it has become an essential tool in the research laboratory. Real-time PCR has engendered wider acceptance of the PCR due to its improved rapidity, sensitivity, reproducibility and the reduced risk of carry-over contamination. There are currently five main chemistries used for the detection of PCR product during real-time PCR. These are the DNA binding fluorophores, the 5' endonuclease, adjacent linear and hairpin oligoprobes and the self-fluorescing amplicons, which are described in detail. We also discuss factors that have restricted the development of multiplex real-time PCR as well as the role of real-time PCR in quantitating nucleic acids. Both amplification hardware and the fluorogenic detection chemistries have evolved rapidly as the understanding of real-time PCR has developed and this review aims to update the scientist on the current state of the art. We describe the background, advantages and limitations of real-time PCR and we review the literature as it applies to virus detection in the routine and research laboratory in order to focus on one of the many areas in which the application of real-time PCR has provided significant methodological benefits and improved patient outcomes. However, the technology discussed has been applied to other areas of microbiology as well as studies of gene expression and genetic disease.

Temperature-dependent time-resolved photoluminescence measurements of (1-101)-oriented semi-polar AlGaN/GaN MQWs

Science.gov (United States)

Rosales, Daniel; Gil, Bernard; Monavarian, Morteza; Zhang, Fan; Okur, Serdal; Izyumskaya, Natalia; Avrutin, Vitaliy; Özgür, Ümit; Morkoç, Hadis

2015-03-01

We studied the temperature dependence and the recombination dynamics of the photoluminescence of (1-101)-oriented semi-polar Al0.2Ga0.8N/GaN multiple quantum wells (MQW). The polarized low-temperature PL measurements reveal that radiative recombination exhibit an anisotropic behavior. The PL intensity at room temperature is reduced by one order of magnitude with respect to low temperature. The radiative decay time exhibits a mixed behavior: it is roughly constant between 8K to ranging near 140-150K and then rapidly increases with a slope of 10 ps.K-1. This behavior is indicative of coexistence of localized excitons and free excitons which relative proportion are statistically computed.

Real time programming environment for Windows

Energy Technology Data Exchange (ETDEWEB)

LaBelle, D.R. [LaBelle (Dennis R.), Clifton Park, NY (United States)

1998-04-01

This document provides a description of the Real Time Programming Environment (RTProE). RTProE tools allow a programmer to create soft real time projects under general, multi-purpose operating systems. The basic features necessary for real time applications are provided by RTProE, leaving the programmer free to concentrate efforts on his specific project. The current version supports Microsoft Windows{trademark} 95 and NT. The tasks of real time synchronization and communication with other programs are handled by RTProE. RTProE includes a generic method for connecting a graphical user interface (GUI) to allow real time control and interaction with the programmer`s product. Topics covered in this paper include real time performance issues, portability, details of shared memory management, code scheduling, application control, Operating System specific concerns and the use of Computer Aided Software Engineering (CASE) tools. The development of RTProE is an important step in the expansion of the real time programming community. The financial costs associated with using the system are minimal. All source code for RTProE has been made publicly available. Any person with access to a personal computer, Windows 95 or NT, and C or FORTRAN compilers can quickly enter the world of real time modeling and simulation.

An In-Home Digital Network Architecture for Real-Time and Non-Real-Time Communication

NARCIS (Netherlands)

Scholten, Johan; Jansen, P.G.; Hanssen, F.T.Y.; Hattink, Tjalling

2002-01-01

This paper describes an in-home digital network architecture that supports both real-time and non-real-time communication. The architecture deploys a distributed token mechanism to schedule communication streams and to offer guaranteed quality-ofservice. Essentially, the token mechanism prevents

MARTe: A Multiplatform Real-Time Framework

Science.gov (United States)

Neto, André C.; Sartori, Filippo; Piccolo, Fabio; Vitelli, Riccardo; De Tommasi, Gianmaria; Zabeo, Luca; Barbalace, Antonio; Fernandes, Horacio; Valcarcel, Daniel F.; Batista, Antonio J. N.

2010-04-01

Development of real-time applications is usually associated with nonportable code targeted at specific real-time operating systems. The boundary between hardware drivers, system services, and user code is commonly not well defined, making the development in the target host significantly difficult. The Multithreaded Application Real-Time executor (MARTe) is a framework built over a multiplatform library that allows the execution of the same code in different operating systems. The framework provides the high-level interfaces with hardware, external configuration programs, and user interfaces, assuring at the same time hard real-time performances. End-users of the framework are required to define and implement algorithms inside a well-defined block of software, named Generic Application Module (GAM), that is executed by the real-time scheduler. Each GAM is reconfigurable with a set of predefined configuration meta-parameters and interchanges information using a set of data pipes that are provided as inputs and required as output. Using these connections, different GAMs can be chained either in series or parallel. GAMs can be developed and debugged in a non-real-time system and, only once the robustness of the code and correctness of the algorithm are verified, deployed to the real-time system. The software also supplies a large set of utilities that greatly ease the interaction and debugging of a running system. Among the most useful are a highly efficient real-time logger, HTTP introspection of real-time objects, and HTTP remote configuration. MARTe is currently being used to successfully drive the plasma vertical stabilization controller on the largest magnetic confinement fusion device in the world, with a control loop cycle of 50 ?s and a jitter under 1 ?s. In this particular project, MARTe is used with the Real-Time Application Interface (RTAI)/Linux operating system exploiting the new ?86 multicore processors technology.

Riccati and Ermakov Equations in Time-Dependent and Time-Independent Quantum Systems

Directory of Open Access Journals (Sweden)

Dieter Schuch

2008-05-01

Full Text Available The time-evolution of the maximum and the width of exact analytic wave packet (WP solutions of the time-dependent Schrödinger equation (SE represents the particle and wave aspects, respectively, of the quantum system. The dynamics of the maximum, located at the mean value of position, is governed by the Newtonian equation of the corresponding classical problem. The width, which is directly proportional to the position uncertainty, obeys a complex nonlinear Riccati equation which can be transformed into a real nonlinear Ermakov equation. The coupled pair of these equations yields a dynamical invariant which plays a key role in our investigation. It can be expressed in terms of a complex variable that linearizes the Riccati equation. This variable also provides the time-dependent parameters that characterize the Green's function, or Feynman kernel, of the corresponding problem. From there, also the relation between the classical and quantum dynamics of the systems can be obtained. Furthermore, the close connection between the Ermakov invariant and the Wigner function will be shown. Factorization of the dynamical invariant allows for comparison with creation/annihilation operators and supersymmetry where the partner potentials fulfil (real Riccati equations. This provides the link to a nonlinear formulation of time-independent quantum mechanics in terms of an Ermakov equation for the amplitude of the stationary state wave functions combined with a conservation law. Comparison with SUSY and the time-dependent problems concludes our analysis.

Real-Time and Real-Fast Performance of General-Purpose and Real-Time Operating Systems in Multithreaded Physical Simulation of Complex Mechanical Systems

Directory of Open Access Journals (Sweden)

Carlos Garre

2014-01-01

Full Text Available Physical simulation is a valuable tool in many fields of engineering for the tasks of design, prototyping, and testing. General-purpose operating systems (GPOS are designed for real-fast tasks, such as offline simulation of complex physical models that should finish as soon as possible. Interfacing hardware at a given rate (as in a hardware-in-the-loop test requires instead maximizing time determinism, for which real-time operating systems (RTOS are designed. In this paper, real-fast and real-time performance of RTOS and GPOS are compared when simulating models of high complexity with large time steps. This type of applications is usually present in the automotive industry and requires a good trade-off between real-fast and real-time performance. The performance of an RTOS and a GPOS is compared by running a tire model scalable on the number of degrees-of-freedom and parallel threads. The benchmark shows that the GPOS present better performance in real-fast runs but worse in real-time due to nonexplicit task switches and to the latency associated with interprocess communication (IPC and task switch.

GNSS global real-time augmentation positioning: Real-time precise satellite clock estimation, prototype system construction and performance analysis

Science.gov (United States)

Chen, Liang; Zhao, Qile; Hu, Zhigang; Jiang, Xinyuan; Geng, Changjiang; Ge, Maorong; Shi, Chuang

2018-01-01

Lots of ambiguities in un-differenced (UD) model lead to lower calculation efficiency, which isn't appropriate for the high-frequency real-time GNSS clock estimation, like 1 Hz. Mixed differenced model fusing UD pseudo-range and epoch-differenced (ED) phase observations has been introduced into real-time clock estimation. In this contribution, we extend the mixed differenced model for realizing multi-GNSS real-time clock high-frequency updating and a rigorous comparison and analysis on same conditions are performed to achieve the best real-time clock estimation performance taking the efficiency, accuracy, consistency and reliability into consideration. Based on the multi-GNSS real-time data streams provided by multi-GNSS Experiment (MGEX) and Wuhan University, GPS + BeiDou + Galileo global real-time augmentation positioning prototype system is designed and constructed, including real-time precise orbit determination, real-time precise clock estimation, real-time Precise Point Positioning (RT-PPP) and real-time Standard Point Positioning (RT-SPP). The statistical analysis of the 6 h-predicted real-time orbits shows that the root mean square (RMS) in radial direction is about 1-5 cm for GPS, Beidou MEO and Galileo satellites and about 10 cm for Beidou GEO and IGSO satellites. Using the mixed differenced estimation model, the prototype system can realize high-efficient real-time satellite absolute clock estimation with no constant clock-bias and can be used for high-frequency augmentation message updating (such as 1 Hz). The real-time augmentation message signal-in-space ranging error (SISRE), a comprehensive accuracy of orbit and clock and effecting the users' actual positioning performance, is introduced to evaluate and analyze the performance of GPS + BeiDou + Galileo global real-time augmentation positioning system. The statistical analysis of real-time augmentation message SISRE is about 4-7 cm for GPS, whlile 10 cm for Beidou IGSO/MEO, Galileo and about 30 cm

Kinetics of the stress induced phase transition in quartz by real-time neutron scattering

International Nuclear Information System (INIS)

Gibhardt, H.; Eckold, G.; Guethoff, F.

1999-01-01

Complete text of publication follows. The stability regime of the incommensurate phase of quartz is influenced by uniaxial stress. Hence, the phase transition can be induced under isothermal conditions by the application of external mechanical forces. Using real-time neutron scattering the time evolution of structural changes is investigated id detail during stress variations. The time dependent behaviour of the satellite reflection is compared with that one of the fundamental Bragg reflection which - via primary extinction - gives information about the perfection of the crystal. On increasing stress the perfection of the lattice is destroyed immediately while the modulated structure is built up with a delay of about 1 s. Decreasing the stress leads to a reverse behaviour. Moreover, there is evidence that under periodical load residual non-relaxed strain fields survive leading to a different temperature dependence as compared to static conditions. This finding is compatible with pronounced hysteresis effects observed under cycling stress. It is argued that these residual strains are associated with non-relaxed topological 4-line defects, that drive the structural changes in quartz (1). (author)

Dynamic compensation temperatures in a mixed spin-1 and spin-3/2 Ising system under a time-dependent oscillating magnetic field

Energy Technology Data Exchange (ETDEWEB)

Keskin, Mustafa, E-mail: keskin@erciyes.edu.t [Department of Physics, Erciyes University, 38039 Kayseri (Turkey); Kantar, Ersin [Institute of Science, Erciyes University, 38039 Kayseri (Turkey)

2010-09-15

We study the existence of dynamic compensation temperatures in the mixed spin-1 and spin-3/2 Ising ferrimagnetic system Hamiltonian with bilinear and crystal-field interactions in the presence of a time-dependent oscillating external magnetic field on a hexagonal lattice. We employ the Glauber transitions rates to construct the mean-field dynamic equations. We investigate the time dependence of an average sublattice magnetizations, the thermal behavior of the dynamic sublattice magnetizations and the total magnetization. From these studies, we find the phases in the system, and characterize the nature (continuous or discontinuous) of transitions as well as obtain the dynamic phase transition (DPT) points and the dynamic compensation temperatures. We also present dynamic phase diagrams, including the compensation temperatures, in the five different planes. A comparison is made with the results of the available mixed spin Ising systems.

Dynamic compensation temperatures in a mixed spin-1 and spin-3/2 Ising system under a time-dependent oscillating magnetic field

International Nuclear Information System (INIS)

Keskin, Mustafa; Kantar, Ersin

2010-01-01

We study the existence of dynamic compensation temperatures in the mixed spin-1 and spin-3/2 Ising ferrimagnetic system Hamiltonian with bilinear and crystal-field interactions in the presence of a time-dependent oscillating external magnetic field on a hexagonal lattice. We employ the Glauber transitions rates to construct the mean-field dynamic equations. We investigate the time dependence of an average sublattice magnetizations, the thermal behavior of the dynamic sublattice magnetizations and the total magnetization. From these studies, we find the phases in the system, and characterize the nature (continuous or discontinuous) of transitions as well as obtain the dynamic phase transition (DPT) points and the dynamic compensation temperatures. We also present dynamic phase diagrams, including the compensation temperatures, in the five different planes. A comparison is made with the results of the available mixed spin Ising systems.

Temperature dependency of external stress corrosion crack propagation of 304 stainless steel

International Nuclear Information System (INIS)

Hayashibara, Hitoshi; Mizutani, Yoshihiro; Mayuzumi, Masami; Tani, Jun-ichi

2010-01-01

Temperature dependency of external stress corrosion cracking (ESCC) of 304 stainless steel was examined with CT specimens. Maximum ESCC propagation rates appeared in the early phase of ESCC propagation. ESCC propagation rates generally became smaller as testing time advance. Temperature dependency of maximum ESCC propagation rate was analyzed with Arrhenius plot, and apparent activation energy was similar to that of SCC in chloride solutions. Temperature dependency of macroscopic ESCC incubation time was different from that of ESCC propagation rate. Anodic current density of 304 stainless steel was also examined by anodic polarization measurement. Temperature dependency of critical current density of active state in artificial sea water solution of pH=1.3 was similar to that of ESCC propagation rate. (author)

Comparison of multiple DNA dyes for real-time PCR: effects of dye concentration and sequence composition on DNA amplification and melting temperature

DEFF Research Database (Denmark)

Guðnason, Haukur; Dufva, Hans Martin; Bang, Dang Duong

2007-01-01

investigate 15 different intercalating DNA dyes for their inhibitory effects on PCR, effects on DNA melting temperature and possible preferential binding to GC-rich sequences. Our results demonstrated that in contrast to the results of SYBR Green I, two intercalating dyes SYTO-13 and SYTO-82 do not inhibit......The importance of real-time polymerase chain reaction (PCR) has increased steadily in clinical applications over the last decade. Many applications utilize SYBR Green I dye to follow the accumulation of amplicons in real time. SYBR Green I has, however, a number of limitations that include...... the inhibition of PCR, preferential binding to GC-rich sequences and effects on melting curve analysis. Although a few alternative dyes without some of these limitations have been recently proposed, no large-scale investigation into the properties of intercalating dyes has been performed. In this study, we...

Scalable Real-Time Negotiation Toolkit

National Research Council Canada - National Science Library

Lesser, Victor

2004-01-01

... to implement an adaptive distributed sensor network. These activities involved the development of a distributed soft, real-time heuristic resource allocation protocol, the development of a domain-independent soft, real time agent architecture...

Temperature-dependence of Threshold Current Density-Length Product in Metallization Lines: A Revisit

International Nuclear Information System (INIS)

Duryat, Rahmat Saptono; Kim, Choong-Un

2016-01-01

One of the important phenomena in Electromigration (EM) is Blech Effect. The existence of Threshold Current Density-Length Product or EM Threshold has such fundamental and technological consequences in the design, manufacture, and testing of electronics. Temperature-dependence of Blech Product had been thermodynamically established and the real behavior of such interconnect materials have been extensively studied. The present paper reviewed the temperature-dependence of EM threshold in metallization lines of different materials and structure as found in relevant published articles. It is expected that the reader can see a big picture from the compiled data, which might be overlooked when it was examined in pieces. (paper)

Model Checking Real-Time Systems

DEFF Research Database (Denmark)

Bouyer, Patricia; Fahrenberg, Uli; Larsen, Kim Guldstrand

2018-01-01

This chapter surveys timed automata as a formalism for model checking real-time systems. We begin with introducing the model, as an extension of finite-state automata with real-valued variables for measuring time. We then present the main model-checking results in this framework, and give a hint...

Modular specification of real-time systems

DEFF Research Database (Denmark)

Inal, Recep

1994-01-01

Duration Calculus, a real-time interval logic, has been embedded in the Z specification language to provide a notation for real-time systems that combines the modularisation and abstraction facilities of Z with a logic suitable for reasoning about real-time properties. In this article the notation...

Quantitative analysis of TEM-8 and CEA tumor markers indicating free tumor cells in the peripheral blood of colorectal cancer patients.

Science.gov (United States)

Raeisossadati, Reza; Farshchian, Moein; Ganji, Azita; Tavassoli, Alieza; Velayati, Arash; Dadkhah, Ezzat; Chavoshi, Somaye; Mehrabi Bahar, Mostafa; Memar, Bahram; Rajabi Mashhadi, Mohammad Taghi; Naseh, Hossein; Forghanifard, Mohammad Mahdi; Moghbeli, Meysam; Moaven, Omeed; Abbaszadegan, Mohammad Reza

2011-10-01

Colorectal cancer (CRC) remains the third most common cancer in the world. Approximately in 50 percent of patients, metastatic disease is a major cause of death. Therefore, early diagnosis of CRC is crucial for a successful outcome. For the detection of circulating cancer cells, this study applied a sensitive method that employed specific tumor markers for early detection. A total of 80 blood samples from 40 CRC patients and 40 age-matched healthy controls were collected for the study. The circulating mRNA levels of two CRC tumor markers, tumor endothelial marker 8 (TEM-8) and carcinoembryogenic antigen (CEA) were evaluated using an absolute quantitative real-time PCR assay in a Stratagene Mx-3000P real-time PCR system. GAPDH was used as the endogenous control. TEM-8 and CEA were primarily detected more in the CRC patients rather than in the controls: 22/40 vs 9/40, p=0.009 and 30/40 vs 11/40, p=0.00054, respectively. In the CRC patients, the mRNA level of these markers was significantly higher in comparison to the normal controls (p=0.018 and 0.01). The overall sensitivity of this panel was 65% with a specificity of 75%. Statistical analysis for demographic variants did not reach significant values. TEM-8 and CEA markers were detected more frequently and in significantly higher levels in the blood samples of patients compared with samples from age-matched healthy controls. The copy number of CEA and TEM-8 mRNA, as detected by a real-time quantitative PCR, appears to be a promising marker for evaluating the risk of tumor spread.

Multiprocessor scheduling for real-time systems

CERN Document Server

Baruah, Sanjoy; Buttazzo, Giorgio

2015-01-01

This book provides a comprehensive overview of both theoretical and pragmatic aspects of resource-allocation and scheduling in multiprocessor and multicore hard-real-time systems.  The authors derive new, abstract models of real-time tasks that capture accurately the salient features of real application systems that are to be implemented on multiprocessor platforms, and identify rules for mapping application systems onto the most appropriate models.  New run-time multiprocessor scheduling algorithms are presented, which are demonstrably better than those currently used, both in terms of run-time efficiency and tractability of off-line analysis.  Readers will benefit from a new design and analysis framework for multiprocessor real-time systems, which will translate into a significantly enhanced ability to provide formally verified, safety-critical real-time systems at a significantly lower cost.

Assessing phase stability and element distribution in Co-base superalloys at elevated temperatures by in situ TEM heating experiments

Energy Technology Data Exchange (ETDEWEB)

Eggeler, Yolita; Mueller, Julian; Spiecker, Erdmann [Lehrstuhl fuer Mikro- und Nanostrukturforschung and Center for Nanoanalysis and Electron Microscopy (CENEM), Department Werkstoffwissenschaften, Universitaet Erlangen-Nuernberg, Erlangen (Germany)

2016-07-01

Co-based alloys, of a composition of Co-12Al-9W, form a stable two phase γ/γ{sup '} microstructure at 900 C. γ{sup '} cubes, consisting of the L12 crystal structure are coherently embedded in a solid solution fcc (A1) γ matrix. To ensure precipitate hardening at temperatures, which are relevant to practical applications, 700-1100 C, as experienced in gas turbine applications, the stability of the γ/γ{sup '} phases is of fundamental importance. In this analysis in situ TEM studies with chip-based heating systems (by DENS solution) are applied on new Co-based superalloys. After in situ heating at apr. 900 C and controlled quenching with different quenching rates the elemental distribution at the γ/γ{sup '} interface is measured using ChemiSTEM EDX. Exploiting the driving force for interface movement resulting from temperature-dependent volume fraction of γ and γ{sup '} insight into the diffusion of individual alloying elements and the relationship between local chemistry and ordering can be gained from transient phenomena. The experimental results will be compared with theoretical calculations. This work has been carried out within the framework of the SFB-TR 103 ''Single Crystal Superalloys''.

Quantification of Artifact Reduction With Real-Time Cine Four-Dimensional Computed Tomography Acquisition Methods

International Nuclear Information System (INIS)

Langner, Ulrich W.; Keall, Paul J.

2010-01-01

Purpose: To quantify the magnitude and frequency of artifacts in simulated four-dimensional computed tomography (4D CT) images using three real-time acquisition methods- direction-dependent displacement acquisition, simultaneous displacement and phase acquisition, and simultaneous displacement and velocity acquisition- and to compare these methods with commonly used retrospective phase sorting. Methods and Materials: Image acquisition for the four 4D CT methods was simulated with different displacement and velocity tolerances for spheres with radii of 0.5 cm, 1.5 cm, and 2.5 cm, using 58 patient-measured tumors and respiratory motion traces. The magnitude and frequency of artifacts, CT doses, and acquisition times were computed for each method. Results: The mean artifact magnitude was 50% smaller for the three real-time methods than for retrospective phase sorting. The dose was ∼50% lower, but the acquisition time was 20% to 100% longer for the real-time methods than for retrospective phase sorting. Conclusions: Real-time acquisition methods can reduce the frequency and magnitude of artifacts in 4D CT images, as well as the imaging dose, but they increase the image acquisition time. The results suggest that direction-dependent displacement acquisition is the preferred real-time 4D CT acquisition method, because on average, the lowest dose is delivered to the patient and the acquisition time is the shortest for the resulting number and magnitude of artifacts.

Temperature dependence of optical properties in Nd/Cr:YAG materials

International Nuclear Information System (INIS)

Honda, Yoshiyuki; Motokoshi, Shinji; Jitsuno, Takahisa; Miyanaga, Noriaki; Fujioka, Kana; Nakatsuka, Masahiro; Yoshida, Minoru

2014-01-01

The energy transfer from Cr 3+ to Nd 3+ for Nd/Cr:YAG (Nd: 1.0%, Cr: 2.0%) materials was investigated by measuring the temperature dependences of fluorescence characteristics. The fluorescence intensity of Nd 3+ increased with temperature owing to enhancement of the absorption coefficient of Cr 3+ . The energy transfer efficiency was constant from 77 to 450 K. The energy transfer time decreased with increasing temperature. -- Highlights: • We investigate the energy transfer from Cr 3+ to Nd 3+ in Nd/Cr:YAG materials by measuring the temperature dependence of fluorescence characteristics. • The fluorescence intensity of Nd 3+ increased with temperature owing to enhancement of the absorption coefficient of Cr 3+ . • The energy transfer efficiency was constant from 77 to 450 K. • The energy transfer time decreased with increasing temperature. • Nd/Cr:YAG ceramics pumped by a flash lamp would not only provide high conversion efficiency, but can also be expected to function as an effective laser operating at high temperature

A wireless batteryless in vivo EKG and core body temperature sensing microsystem with 60 Hz suppression technique for untethered genetically engineered mice real-time monitoring.

Science.gov (United States)

Chaimanonart, Nattapon; Young, Darrin J

2009-01-01

A wireless, batteryless, and implantable EKG and core body temperature sensing microsystem with adaptive RF powering for untethered genetically engineered mice real-time monitoring is designed, implemented, and in vivo characterized. A packaged microsystem, exhibiting a total size of 9 mm x 7 mm x 3 mm with a weight of 400 mg including a pair of stainless-steel EKG electrodes, is implanted in a mouse abdomen for real-time monitoring. A low power 2 mm x 2 mm ASIC, consisting of an EKG amplifier, a proportional-to-absolute-temperature (PTAT)-based temperature sensor, an RF power sensing circuit, an RF-DC power converter, an 8-bit ADC, digital control circuitry, and a 433 MHz FSK transmitter, is powered by an adaptively controlled external RF energy source at 4 MHz to ensure a stable 2V supply with 156microA current driving capability for the overall microsystem. An electrical model for analyzing 60 Hz interference based on 2-electrode and 3-electrode configurations is proposed and compared with in vivo evaluation results. Due to the small laboratory animal chest area, a 60 Hz suppression technique by employing input termination resistors is chosen for two-EKG-electrode implant configuration.

Prototyping real-time systems

OpenAIRE

Clynch, Gary

1994-01-01

The traditional software development paradigm, the waterfall life cycle model, is defective when used for developing real-time systems. This thesis puts forward an executable prototyping approach for the development of real-time systems. A prototyping system is proposed which uses ESML (Extended Systems Modelling Language) as a prototype specification language. The prototyping system advocates the translation of non-executable ESML specifications into executable LOOPN (Language of Object ...

Constitutive modeling for uniaxial time-dependent ratcheting of SS304 stainless steel

International Nuclear Information System (INIS)

Kan Qianhua; Kang Guozheng; Zhang Juan

2007-01-01

Based on the experimental results of uniaxial time-dependent ratcheting behavior of SS304 stainless steel at room temperature and 973K, a new time-dependent constitutive model was proposed. The model describes the time-dependent ratcheting by adding a static/thermal recovery into the Abdel-Karim-Ohno non-linear kinematic hardening rule. The capability of the model to describe the time-dependent ratcheting was discussed by comparing the simulations with the corresponding experimental results. It is shown that the revised unified viscoplastic model can simulate the time-dependent ratcheting reasonably both at room and high temperatures. (authors)

A real-time low energy electron calorimeter

International Nuclear Information System (INIS)

Mod Ali, N.; Smith, F.A.

1999-01-01

A real-time low energy electron calorimeter with a thin film window has been designed and fabricated to facilitate a reliable method of dose assessment for electron beam energies down to 200 keV. The work was initiated by the Radiation Physics Group of Queen Mary and Westfield College in collaboration with the National Physical Laboratory (NPL), Teddington. Irradiations were performed on the low and medium electron energy electron accelerators at the Malaysian Institute for Nuclear Technology Research (MINT). Calorimeter response was initially tested using the on-line temperature measurements for a 500-keV electron beam. The system was later redesigned by incorporating a data-logger to use on the self-shielded 200-keV beam. In use, the final version of the calorimeter could start logging temperature a short time before the calorimeter passed under the beam and continue measurements throughout the irradiation. Data could be easily retrieved at the end of the exposure. (author)

Software Design Methods for Real-Time Systems

Science.gov (United States)

1989-12-01

This module describes the concepts and methods used in the software design of real time systems . It outlines the characteristics of real time systems , describes...the role of software design in real time system development, surveys and compares some software design methods for real - time systems , and

Real-time Pricing in Power Markets

DEFF Research Database (Denmark)

Boom, Anette; Schwenen, Sebastian

We examine welfare e ects of real-time pricing in electricity markets. Before stochastic energy demand is known, competitive retailers contract with nal consumers who exogenously do not have real-time meters. After demand is realized, two electricity generators compete in a uniform price auction...... to satisfy demand from retailers acting on behalf of subscribed customers and from consumers with real-time meters. Increasing the number of consumers on real-time pricing does not always increase welfare since risk-averse consumers dislike uncertain and high prices arising through market power...

Real-time Pricing in Power Markets

DEFF Research Database (Denmark)

Boom, Anette; Schwenen, Sebastian

We examine welfare eects of real-time pricing in electricity markets. Before stochastic energy demand is known, competitive retailers contract with nal consumers who exogenously do not have real-time meters. After demand is realized, two electricity generators compete in a uniform price auction...... to satisfy demand from retailers acting on behalf of subscribed customers and from consumers with real-time meters. Increasing the number of consumers on real-time pricing does not always increase welfare since risk-averse consumers dislike uncertain and high prices arising through market power...

Distributed, Embedded and Real-time Java Systems

CERN Document Server

Wellings, Andy

2012-01-01

Research on real-time Java technology has been prolific over the past decade, leading to a large number of corresponding hardware and software solutions, and frameworks for distributed and embedded real-time Java systems.  This book is aimed primarily at researchers in real-time embedded systems, particularly those who wish to understand the current state of the art in using Java in this domain.  Much of the work in real-time distributed, embedded and real-time Java has focused on the Real-time Specification for Java (RTSJ) as the underlying base technology, and consequently many of the Chapters in this book address issues with, or solve problems using, this framework. Describes innovative techniques in: scheduling, memory management, quality of service and communication systems supporting real-time Java applications; Includes coverage of multiprocessor embedded systems and parallel programming; Discusses state-of-the-art resource management for embedded systems, including Java’s real-time garbage collect...

Research of real-time communication software

Science.gov (United States)

Li, Maotang; Guo, Jingbo; Liu, Yuzhong; Li, Jiahong

2003-11-01

Real-time communication has been playing an increasingly important role in our work, life and ocean monitor. With the rapid progress of computer and communication technique as well as the miniaturization of communication system, it is needed to develop the adaptable and reliable real-time communication software in the ocean monitor system. This paper involves the real-time communication software research based on the point-to-point satellite intercommunication system. The object-oriented design method is adopted, which can transmit and receive video data and audio data as well as engineering data by satellite channel. In the real-time communication software, some software modules are developed, which can realize the point-to-point satellite intercommunication in the ocean monitor system. There are three advantages for the real-time communication software. One is that the real-time communication software increases the reliability of the point-to-point satellite intercommunication system working. Second is that some optional parameters are intercalated, which greatly increases the flexibility of the system working. Third is that some hardware is substituted by the real-time communication software, which not only decrease the expense of the system and promotes the miniaturization of communication system, but also aggrandizes the agility of the system.

In situ TEM observation of solid-gas reactions

International Nuclear Information System (INIS)

Kishita, K; Kamino, T; Watabe, A; Kuroda, K; Saka, H

2008-01-01

Under a gaseous atmosphere at high temperatures, almost all the materials (metal, catalysts, etc.) change their structures and properties. For the research and development of materials, it is of vital importance to clarify mechanisms of solid-gas and liquid-gas reactions. Recently an in situ TEM system combined with an environmental holder, which has a gas injection nozzle close to a specimen-heating element, has been developed. The gas injection nozzle permits gas to flow around the specimens sitting on the heating element made of a fine W filament. The newly developed in situ TEM has a differential pumping system; therefore, the pressure in the specimen chamber is maintained in the range of higher than 1 Pa, while the pressure in the electron gun chamber can be kept in the range of 10 -5 Pa. This system was applied to in situ observation of chemical reactions of metals with gases: Observation of oxidation and reduction under a gas pressure ranging from 10 -5 Pa to 1 Pa at high temperatures (room temperature to ∼1473 K) were successfully carried out on pure metal and rare metal catalysts at near-atomic resolution. This in situ environmental TEM system is promising for clarifying mechanisms of many solid-gas and liquid-gas reactions that take place at high temperatures under a gas atmosphere.

On-line diagnostics for a real time system

International Nuclear Information System (INIS)

Sreenivasan, P.

1976-01-01

The purpose of an on-line diagnostics is to infuse the ability of self diagnosing in an online computer to enhance its dependability in a real time system. Such a diagnostics evolved for the CDPS of the Fast Breeder Test Reactor at Kalpakkam is reported. The two phases of the diagnostics, i.e., the malfunction detection and post detection action are described in some detail. (A.K.)

The temperature dependent amide I band of crystalline acetanilide

Energy Technology Data Exchange (ETDEWEB)

Cruzeiro, Leonor [CCMAR, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Physics Department, FCT, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Freedman, Holly [CCMAR, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

2013-10-01

The temperature dependent anomalous peak in the amide I band of crystalline acetanilide is thought to be due to self-trapped states. On the contrary, according to the present model, the anomalous peak comes from the fraction of ACN molecules strongly hydrogen-bonded to a neighboring ACN molecule, and its intensity decreases because, on average, this fraction decreases as temperature increases. This model provides, for the first time, an integrated and theoretically consistent view of the temperature dependence of the full amide I band and a qualitative explanation of some of the features of nonlinear pump–probe experiments.

The temperature dependent amide I band of crystalline acetanilide

Science.gov (United States)

Cruzeiro, Leonor; Freedman, Holly

2013-10-01

The temperature dependent anomalous peak in the amide I band of crystalline acetanilide is thought to be due to self-trapped states. On the contrary, according to the present model, the anomalous peak comes from the fraction of ACN molecules strongly hydrogen-bonded to a neighboring ACN molecule, and its intensity decreases because, on average, this fraction decreases as temperature increases. This model provides, for the first time, an integrated and theoretically consistent view of the temperature dependence of the full amide I band and a qualitative explanation of some of the features of nonlinear pump-probe experiments.

The temperature dependent amide I band of crystalline acetanilide

International Nuclear Information System (INIS)

Cruzeiro, Leonor; Freedman, Holly

2013-01-01

The temperature dependent anomalous peak in the amide I band of crystalline acetanilide is thought to be due to self-trapped states. On the contrary, according to the present model, the anomalous peak comes from the fraction of ACN molecules strongly hydrogen-bonded to a neighboring ACN molecule, and its intensity decreases because, on average, this fraction decreases as temperature increases. This model provides, for the first time, an integrated and theoretically consistent view of the temperature dependence of the full amide I band and a qualitative explanation of some of the features of nonlinear pump–probe experiments.

2D Inversion of Transient Electromagnetic Method (TEM)

Science.gov (United States)

Bortolozo, Cassiano Antonio; Luís Porsani, Jorge; Acácio Monteiro dos Santos, Fernando

2017-04-01

A new methodology was developed for 2D inversion of Transient Electromagnetic Method (TEM). The methodology consists in the elaboration of a set of routines in Matlab code for modeling and inversion of TEM data and the determination of the most efficient field array for the problem. In this research, the 2D TEM modeling uses the finite differences discretization. To solve the inversion problem, were applied an algorithm based on Marquardt technique, also known as Ridge Regression. The algorithm is stable and efficient and it is widely used in geoelectrical inversion problems. The main advantage of 1D survey is the rapid data acquisition in a large area, but in regions with two-dimensional structures or that need more details, is essential to use two-dimensional interpretation methodologies. For an efficient field acquisition we used in an innovative form the fixed-loop array, with a square transmitter loop (200m x 200m) and 25m spacing between the sounding points. The TEM surveys were conducted only inside the transmitter loop, in order to not deal with negative apparent resistivity values. Although it is possible to model the negative values, it makes the inversion convergence more difficult. Therefore the methodology described above has been developed in order to achieve maximum optimization of data acquisition. Since it is necessary only one transmitter loop disposition in the surface for each series of soundings inside the loop. The algorithms were tested with synthetic data and the results were essential to the interpretation of the results with real data and will be useful in future situations. With the inversion of the real data acquired over the Paraná Sedimentary Basin (PSB) was successful realized a 2D TEM inversion. The results indicate a robust geoelectrical characterization for the sedimentary and crystalline aquifers in the PSB. Therefore, using a new and relevant approach for 2D TEM inversion, this research effectively contributed to map the most

Photon propagators at finite temperature

International Nuclear Information System (INIS)

Yee, J.H.

1982-07-01

We have used the real time formalism to compute the one-loop finite temperature corrections to the photon self energies in spinor and scalar QED. We show that, for a real photon, only the transverse components develop the temperature-dependent masses, while, for an external static electromagnetic field applied to the finite temperature system, only the static electric field is screened by thermal fluctuations. After showing how to compute systematically the imaginary parts of the finite temperature Green functions, we have attempted to give a microscopic interpretation of the imaginary parts of the self energies. (author)

The Time-Dependent Multiple-Vehicle Prize-Collecting Arc Routing Problem

DEFF Research Database (Denmark)

Black, Daniel; Eglese, Richard; Wøhlk, Sanne

2015-01-01

-life traffic situations where the travel times change with the time of day are taken into account. Two metaheuristic algorithms, one based on Variable Neighborhood Search and one based on Tabu Search, are proposed and tested for a set of benchmark problems, generated from real road networks and travel time......In this paper, we introduce a multi vehicle version of the Time-Dependent Prize-Collecting Arc Routing Problem (TD-MPARP). It is inspired by a situation where a transport manager has to choose between a number of full truck load pick-ups and deliveries to be performed by a fleet of vehicles. Real...

In-situ observation of oxidation of Ti(0001) surface by real-time photoelectron spectroscopy using synchrotron radiation

CERN Document Server

Takakuwa, Y; Yoshigoe, A; Teraoka, Y; Mizuno, Y; Tonda, H; Homma, T

2003-01-01

Temperature dependence of the initial oxidation kinetics of Ti(0001) surface was investigated by low energy electron diffraction (LEED) and real-time photoelectron spectroscopy using synchrotron radiation of surface- and bulk-sensitive photon energies. LEED observation revealed that oxide layers grow epitaxially with different surface structures depending on temperature: 1x1 at 200degC and sq root 3 x sq root 3 at 400degC. From the oxygen uptake curve measured by O 1s photo-electron intensity, it was clarified that oxygen diffusion through the epitaxially grown oxide layer is significantly enhanced with raising temperature, making the oxide layer thicker than 70A at 400degC. The chemical shift components observed for Ti 2p showed that TiO sub 2 becomes predominant at the subsurface with O sub 2 dose, while the stoichiometry of oxide near the interface is maintained as TiO and Ti sub 2 O sub 3 , for both cases at 200degC and 400degC. Thus it is concluded that the epitaxial growth of a very thin oxide on the Ti...

Integration of MDSplus in real-time systems

International Nuclear Information System (INIS)

Luchetta, A.; Manduchi, G.; Taliercio, C.

2006-01-01

RFX-mod makes extensive usage of real-time systems for feedback control and uses MDSplus to interface them to the main Data Acquisition system. For this purpose, the core of MDSplus has been ported to VxWorks, the operating system used for real-time control in RFX. Using this approach, it is possible to integrate real-time systems, but MDSplus is used only for non-real-time tasks, i.e. those tasks which are executed before and after the pulse and whose performance does not affect the system time constraints. More extensive use of MDSplus in real-time systems is foreseen, and a real-time layer for MDSplus is under development, which will provide access to memory-mapped pulse files, shared by the tasks running on the same CPU. Real-time communication will also be integrated in the MDSplus core to provide support for distributed memory-mapped pulse files

Preparation of carbon-free TEM microgrids by metal sputtering

International Nuclear Information System (INIS)

Janbroers, S.; Kruijff, T.R. de; Xu, Q.; Kooyman, P.J.; Zandbergen, H.W.

2009-01-01

A new method for preparing carbon-free, temperature-stable Transmission Electron Microscope (TEM) grids is presented. An 80% Au/20% Pd metal film is deposited onto a 'holey' microgrid carbon supported on standard mixed-mesh Au TEM grids. Subsequently, the carbon film is selectively removed using plasma cleaning. In this way, an all-metal TEM film is made containing the 'same' microgrid as the original carbon film. Although electron transparency of the foil is reduced significantly, the open areas for TEM inspection of material over these areas are maintained. The metal foil can be prepared with various thicknesses and ensures good electrical conductivity. The new Au/Pd grids are stable to at least 775 K under vacuum conditions.

Preparation of carbon-free TEM microgrids by metal sputtering.

Science.gov (United States)

Janbroers, S; de Kruijff, T R; Xu, Q; Kooyman, P J; Zandbergen, H W

2009-08-01

A new method for preparing carbon-free, temperature-stable Transmission Electron Microscope (TEM) grids is presented. An 80% Au/20% Pd metal film is deposited onto a 'holey' microgrid carbon supported on standard mixed-mesh Au TEM grids. Subsequently, the carbon film is selectively removed using plasma cleaning. In this way, an all-metal TEM film is made containing the 'same' microgrid as the original carbon film. Although electron transparency of the foil is reduced significantly, the open areas for TEM inspection of material over these areas are maintained. The metal foil can be prepared with various thicknesses and ensures good electrical conductivity. The new Au/Pd grids are stable to at least 775K under vacuum conditions.

Temperature dependant thermal and mechanical properties of a metal-phase change layer interface using the time resolved pump probe technique

International Nuclear Information System (INIS)

Schick, V; Battaglia, J-L; Kusiak, A; Rossignol, C; Wiemer, C

2011-01-01

Time Resolved Pump Probe (TRPP) technique has been implemented to study the thermal and mechanical properties of Ge 2 Sb 2 Te 5 (GST) film deposited on a silicon substrate. According to the knowledge of the thermal properties of the GST layer, the temperature dependant Thermal Boundary Resistance (TBR) at the metal-GST interface is evaluated. Measuring the acoustic oscillation and more particularly its damping leads to characterize the adhesion at the metal - GST interface. This quantity can be efficiently related to the temperature dependent TBR in the 25 deg. C - 400 deg. C range. The TBR increases with temperature and follows the changes of the crystalline structure of materials. A linear relation between the acoustic reflection coefficient and the logarithm of the thermal boundary resistance is found.

Correlation between temperature dependence of elastic moduli and Debye temperature of paramagnetic metal

International Nuclear Information System (INIS)

Bodryakov, V.Yu.; Povzner, A.A.

2000-01-01

The correlation between the temperature dependence of elastic moduli and the Debye temperature of paramagnetic metal is analyzed in neglect of the temperature dependence of the Poison coefficient σ within the frames of the Debye-Grueneisen presentations. It is shown, that namely the temperature dependence of the elastic moduli determines primarily the temperature dependence of the Debye temperature Θ(T). On the other hand, the temperature dependence Θ(T) very weakly effects the temperature dependence of the elastic moduli. The later made it possible to formulate the self-consistent approach to calculation of the elastic moduli temperature dependence. The numerical estimates of this dependence parameters are conducted by the example of the all around compression modulus of the paramagnetic lutetium [ru

Dense time discretization technique for verification of real time systems

International Nuclear Information System (INIS)

Makackas, Dalius; Miseviciene, Regina

2016-01-01

Verifying the real-time system there are two different models to control the time: discrete and dense time based models. This paper argues a novel verification technique, which calculates discrete time intervals from dense time in order to create all the system states that can be reached from the initial system state. The technique is designed for real-time systems specified by a piece-linear aggregate approach. Key words: real-time system, dense time, verification, model checking, piece-linear aggregate

XpertTrack: Precision Autonomous Measuring Device Developed for Real Time Shipments Tracker.

Science.gov (United States)

Viman, Liviu; Daraban, Mihai; Fizesan, Raul; Iuonas, Mircea

2016-03-10

This paper proposes a software and hardware solution for real time condition monitoring applications. The proposed device, called XpertTrack, exchanges data through the GPRS protocol over a GSM network and monitories temperature and vibrations of critical merchandise during commercial shipments anywhere on the globe. Another feature of this real time tracker is to provide GPS and GSM positioning with a precision of 10 m or less. In order to interpret the condition of the merchandise, the data acquisition, analysis and visualization are done with 0.1 °C accuracy for the temperature sensor, and 10 levels of shock sensitivity for the acceleration sensor. In addition to this, the architecture allows increasing the number and the types of sensors, so that companies can use this flexible solution to monitor a large percentage of their fleet.

Betweenness in time dependent networks

International Nuclear Information System (INIS)

Alsayed, Ahmad; Higham, Desmond J.

2015-01-01

The concept of betweenness has given rise to a very useful class of network centrality measures. Loosely, betweenness quantifies the level of importance of a node in terms of its propensity to act as an intermediary when messages are passed around the network. In this work we generalize a walk-based betweenness measure to the case of time-dependent networks, such as those arising in telecommunications and on-line social media. We also introduce a new kind of betweenness measure, temporal betweenness, which quantifies the importance of a time-point. We illustrate the effectiveness of these new measures on synthetic examples, and also give results on real data sets involving voice call, email and Twitter

Real-time temperature estimation and monitoring of HIFU ablation through a combined modeling and passive acoustic mapping approach

International Nuclear Information System (INIS)

Jensen, C R; Cleveland, R O; Coussios, C C

2013-01-01

Passive acoustic mapping (PAM) has been recently demonstrated as a method of monitoring focused ultrasound therapy by reconstructing the emissions created by inertially cavitating bubbles (Jensen et al 2012 Radiology 262 252–61). The published method sums energy emitted by cavitation from the focal region within the tissue and uses a threshold to determine when sufficient energy has been delivered for ablation. The present work builds on this approach to provide a high-intensity focused ultrasound (HIFU) treatment monitoring software that displays both real-time temperature maps and a prediction of the ablated tissue region. This is achieved by determining heat deposition from two sources: (i) acoustic absorption of the primary HIFU beam which is calculated via a nonlinear model, and (ii) absorption of energy from bubble acoustic emissions which is estimated from measurements. The two sources of heat are used as inputs to the bioheat equation that gives an estimate of the temperature of the tissue as well as estimates of tissue ablation. The method has been applied to ex vivo ox liver samples and the estimated temperature is compared to the measured temperature and shows good agreement, capturing the effect of cavitation-enhanced heating on temperature evolution. In conclusion, it is demonstrated that by using PAM and predictions of heating it is possible to produce an evolving estimate of cell death during exposure in order to guide treatment for monitoring ablative HIFU therapy. (paper)

Electron dynamics in complex environments with real-time time dependent density functional theory in a QM-MM framework

International Nuclear Information System (INIS)

Morzan, Uriel N.; Ramírez, Francisco F.; Scherlis, Damián A.; Oviedo, M. Belén; Sánchez, Cristián G.; Lebrero, Mariano C. González

2014-01-01

This article presents a time dependent density functional theory (TDDFT) implementation to propagate the Kohn-Sham equations in real time, including the effects of a molecular environment through a Quantum-Mechanics Molecular-Mechanics (QM-MM) hamiltonian. The code delivers an all-electron description employing Gaussian basis functions, and incorporates the Amber force-field in the QM-MM treatment. The most expensive parts of the computation, comprising the commutators between the hamiltonian and the density matrix—required to propagate the electron dynamics—, and the evaluation of the exchange-correlation energy, were migrated to the CUDA platform to run on graphics processing units, which remarkably accelerates the performance of the code. The method was validated by reproducing linear-response TDDFT results for the absorption spectra of several molecular species. Two different schemes were tested to propagate the quantum dynamics: (i) a leap-frog Verlet algorithm, and (ii) the Magnus expansion to first-order. These two approaches were confronted, to find that the Magnus scheme is more efficient by a factor of six in small molecules. Interestingly, the presence of iron was found to seriously limitate the length of the integration time step, due to the high frequencies associated with the core-electrons. This highlights the importance of pseudopotentials to alleviate the cost of the propagation of the inner states when heavy nuclei are present. Finally, the methodology was applied to investigate the shifts induced by the chemical environment on the most intense UV absorption bands of two model systems of general relevance: the formamide molecule in water solution, and the carboxy-heme group in Flavohemoglobin. In both cases, shifts of several nanometers are observed, consistently with the available experimental data

Neoclassical and gyrokinetic analysis of time-dependent helium transport experiments on MAST

Science.gov (United States)

Henderson, S. S.; Garzotti, L.; Casson, F. J.; Dickinson, D.; Fox, M. F. J.; O'Mullane, M.; Patel, A.; Roach, C. M.; Summers, H. P.; Valovič, M.; The MAST Team

2014-09-01

Time-dependent helium gas puff experiments have been performed on the Mega Ampère Spherical Tokamak (MAST) during a two point plasma current scan in L-mode and a confinement scan at 900 kA. An evaluation of the He II (n = 4 → 3) spectrum line induced by charge exchange suggests anomalous rates of diffusion and inward convection in the outer regions of both L-mode plasmas. Similar rates of diffusion are found in the H-mode plasma, however these rates are consistent with neoclassical predictions. The anomalous inward pinch found in the core of L-mode plasmas is also not apparent in the H-mode core. Linear gyrokinetic simulations of one flux surface in L-mode using the GS2 and GKW codes find that equilibrium flow shear is sufficient to stabilize ITG modes, consistent with beam emission spectroscopy (BES) observations, and suggest that collisionless TEMs may dominate the anomalous helium particle transport. A quasilinear estimate of the dimensionless peaking factor associated with TEMs is in good agreement with experiment. Collisionless TEMs are more stable in H-mode because the electron density gradient is flatter. The steepness of this gradient is therefore pivotal in determining the inward neoclassical particle pinch and the particle flux associated with TEM turbulence.

On Building a Scalable Real-Time Fault-Tolerant System for Embedded Applications

National Research Council Canada - National Science Library

Abdelzaher, T

2001-01-01

.... This raises the challenge of constructing dependable and predictable real-time services for application developers on top of the inexpensive hardware and software components which has minimal support...

Portable inference engine: An extended CLIPS for real-time production systems

Science.gov (United States)

Le, Thach; Homeier, Peter

1988-01-01

The present C-Language Integrated Production System (CLIPS) architecture has not been optimized to deal with the constraints of real-time production systems. Matching in CLIPS is based on the Rete Net algorithm, whose assumption of working memory stability might fail to be satisfied in a system subject to real-time dataflow. Further, the CLIPS forward-chaining control mechanism with a predefined conflict resultion strategy may not effectively focus the system's attention on situation-dependent current priorties, or appropriately address different kinds of knowledge which might appear in a given application. Portable Inference Engine (PIE) is a production system architecture based on CLIPS which attempts to create a more general tool while addressing the problems of real-time expert systems. Features of the PIE design include a modular knowledge base, a modified Rete Net algorithm, a bi-directional control strategy, and multiple user-defined conflict resolution strategies. Problems associated with real-time applications are analyzed and an explanation is given for how the PIE architecture addresses these problems.

Storm real-time processing cookbook

CERN Document Server

Anderson, Quinton

2013-01-01

A Cookbook with plenty of practical recipes for different uses of Storm.If you are a Java developer with basic knowledge of real-time processing and would like to learn Storm to process unbounded streams of data in real time, then this book is for you.

Time-dependent deformation at elevated temperatures in basalt from El Hierro, Stromboli and Teide volcanoes

Science.gov (United States)

Benson, P. M.; Fahrner, D.; Harnett, C. E.; Fazio, M.

2014-12-01

Time dependent deformation describes the process whereby brittle materials deform at a stress level below their short-term material strength (Ss), but over an extended time frame. Although generally well understood in engineering (where it is known as static fatigue or "creep"), knowledge of how rocks creep and fail has wide ramifications in areas as diverse as mine tunnel supports and the long term stability of critically loaded rock slopes. A particular hazard relates to the instability of volcano flanks. A large number of flank collapses are known such as Stromboli (Aeolian islands), Teide, and El Hierro (Canary Islands). Collapses on volcanic islands are especially complex as they necessarily involve the combination of active tectonics, heat, and fluids. Not only does the volcanic system generate stresses that reach close to the failure strength of the rocks involved, but when combined with active pore fluid the process of stress corrosion allows the rock mass to deform and creep at stresses far lower than Ss. Despite the obvious geological hazard that edifice failure poses, the phenomenon of creep in volcanic rocks at elevated temperatures has yet to be thoroughly investigated in a well controlled laboratory setting. We present new data using rocks taken from Stromboli, El Heirro and Teide volcanoes in order to better understand the interplay between the fundamental rock mechanics of these basalts and the effects of elevated temperature fluids (activating stress corrosion mechanisms). Experiments were conducted over short (30-60 minute) and long (8-10 hour) time scales. For this, we use the method of Heap et al., (2011) to impose a constant stress (creep) domain deformation monitored via non-contact axial displacement transducers. This is achieved via a conventional triaxial cell to impose shallow conditions of pressure (<25 MPa) and temperature (<200 °C), and equipped with a 3D laboratory seismicity array (known as acoustic emission, AE) to monitor the micro

Mixed - mode Operating System for Real - time Performance

Directory of Open Access Journals (Sweden)

Hasan M. M.

2017-11-01

Full Text Available The purpose of the mixed-mode system research is to handle devices with the accuracy of real-time systems and at the same time, having all the benefits and facilities of a matured Graphic User Interface(GUIoperating system which is typicallynon-real-time. This mixed-mode operating system comprising of a real-time portion and a non-real-time portion was studied and implemented to identify the feasibilities and performances in practical applications (in the context of scheduled the real-time events. In this research an i8751 microcontroller-based hardware was used to measure the performance of the system in real-time-only as well as non-real-time-only configurations. The real-time portion is an 486DX-40 IBM PC system running under DOS-based real-time kernel and the non-real-time portion is a Pentium IIIbased system running under Windows NT. It was found that mixed-mode systems performed as good as a typical real-time system and in fact, gave many additional benefits such as simplified/modular programming and load tolerance.

A RED modified weighted moving average for soft real-time application

Directory of Open Access Journals (Sweden)

Domanśka Joanna

2014-09-01

Full Text Available The popularity of TCP/IP has resulted in an increase in usage of best-effort networks for real-time communication. Much effort has been spent to ensure quality of service for soft real-time traffic over IP networks. The Internet Engineering Task Force has proposed some architecture components, such as Active Queue Management (AQM. The paper investigates the influence of the weighted moving average on packet waiting time reduction for an AQM mechanism: the RED algorithm. The proposed method for computing the average queue length is based on a difference equation (a recursive equation. Depending on a particular optimality criterion, proper parameters of the modified weighted moving average function can be chosen. This change will allow reducing the number of violations of timing constraints and better use of this mechanism for soft real-time transmissions. The optimization problem is solved through simulations performed in OMNeT++ and later verified experimentally on a Linux implementation

Real-Time Alpine Measurement System Using Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Sami A. Malek

2017-11-01

Full Text Available Monitoring the snow pack is crucial for many stakeholders, whether for hydro-power optimization, water management or flood control. Traditional forecasting relies on regression methods, which often results in snow melt runoff predictions of low accuracy in non-average years. Existing ground-based real-time measurement systems do not cover enough physiographic variability and are mostly installed at low elevations. We present the hardware and software design of a state-of-the-art distributed Wireless Sensor Network (WSN-based autonomous measurement system with real-time remote data transmission that gathers data of snow depth, air temperature, air relative humidity, soil moisture, soil temperature, and solar radiation in physiographically representative locations. Elevation, aspect, slope and vegetation are used to select network locations, and distribute sensors throughout a given network location, since they govern snow pack variability at various scales. Three WSNs were installed in the Sierra Nevada of Northern California throughout the North Fork of the Feather River, upstream of the Oroville dam and multiple powerhouses along the river. The WSNs gathered hydrologic variables and network health statistics throughout the 2017 water year, one of northern Sierra’s wettest years on record. These networks leverage an ultra-low-power wireless technology to interconnect their components and offer recovery features, resilience to data loss due to weather and wildlife disturbances and real-time topological visualizations of the network health. Data show considerable spatial variability of snow depth, even within a 1 km 2 network location. Combined with existing systems, these WSNs can better detect precipitation timing and phase in, monitor sub-daily dynamics of infiltration and surface runoff during precipitation or snow melt, and inform hydro power managers about actual ablation and end-of-season date across the landscape.

Real-Time Alpine Measurement System Using Wireless Sensor Networks.

Science.gov (United States)

Malek, Sami A; Avanzi, Francesco; Brun-Laguna, Keoma; Maurer, Tessa; Oroza, Carlos A; Hartsough, Peter C; Watteyne, Thomas; Glaser, Steven D

2017-11-09

Monitoring the snow pack is crucial for many stakeholders, whether for hydro-power optimization, water management or flood control. Traditional forecasting relies on regression methods, which often results in snow melt runoff predictions of low accuracy in non-average years. Existing ground-based real-time measurement systems do not cover enough physiographic variability and are mostly installed at low elevations. We present the hardware and software design of a state-of-the-art distributed Wireless Sensor Network (WSN)-based autonomous measurement system with real-time remote data transmission that gathers data of snow depth, air temperature, air relative humidity, soil moisture, soil temperature, and solar radiation in physiographically representative locations. Elevation, aspect, slope and vegetation are used to select network locations, and distribute sensors throughout a given network location, since they govern snow pack variability at various scales. Three WSNs were installed in the Sierra Nevada of Northern California throughout the North Fork of the Feather River, upstream of the Oroville dam and multiple powerhouses along the river. The WSNs gathered hydrologic variables and network health statistics throughout the 2017 water year, one of northern Sierra's wettest years on record. These networks leverage an ultra-low-power wireless technology to interconnect their components and offer recovery features, resilience to data loss due to weather and wildlife disturbances and real-time topological visualizations of the network health. Data show considerable spatial variability of snow depth, even within a 1 km 2 network location. Combined with existing systems, these WSNs can better detect precipitation timing and phase in, monitor sub-daily dynamics of infiltration and surface runoff during precipitation or snow melt, and inform hydro power managers about actual ablation and end-of-season date across the landscape.

Research in Distributed Real-Time Systems

Science.gov (United States)

Mukkamala, R.

1997-01-01

This document summarizes the progress we have made on our study of issues concerning the schedulability of real-time systems. Our study has produced several results in the scalability issues of distributed real-time systems. In particular, we have used our techniques to resolve schedulability issues in distributed systems with end-to-end requirements. During the next year (1997-98), we propose to extend the current work to address the modeling and workload characterization issues in distributed real-time systems. In particular, we propose to investigate the effect of different workload models and component models on the design and the subsequent performance of distributed real-time systems.

The Influence of Temperature on Time-Dependent Deformation and Failure in Granite: A Mesoscale Modeling Approach

Science.gov (United States)

Xu, T.; Zhou, G. L.; Heap, Michael J.; Zhu, W. C.; Chen, C. F.; Baud, Patrick

2017-09-01

An understanding of the influence of temperature on brittle creep in granite is important for the management and optimization of granitic nuclear waste repositories and geothermal resources. We propose here a two-dimensional, thermo-mechanical numerical model that describes the time-dependent brittle deformation (brittle creep) of low-porosity granite under different constant temperatures and confining pressures. The mesoscale model accounts for material heterogeneity through a stochastic local failure stress field, and local material degradation using an exponential material softening law. Importantly, the model introduces the concept of a mesoscopic renormalization to capture the co-operative interaction between microcracks in the transition from distributed to localized damage. The mesoscale physico-mechanical parameters for the model were first determined using a trial-and-error method (until the modeled output accurately captured mechanical data from constant strain rate experiments on low-porosity granite at three different confining pressures). The thermo-physical parameters required for the model, such as specific heat capacity, coefficient of linear thermal expansion, and thermal conductivity, were then determined from brittle creep experiments performed on the same low-porosity granite at temperatures of 23, 50, and 90 °C. The good agreement between the modeled output and the experimental data, using a unique set of thermo-physico-mechanical parameters, lends confidence to our numerical approach. Using these parameters, we then explore the influence of temperature, differential stress, confining pressure, and sample homogeneity on brittle creep in low-porosity granite. Our simulations show that increases in temperature and differential stress increase the creep strain rate and therefore reduce time-to-failure, while increases in confining pressure and sample homogeneity decrease creep strain rate and increase time-to-failure. We anticipate that the

Real-time data access layer for MDSplus

International Nuclear Information System (INIS)

Manduchi, G.; Luchetta, A.; Taliercio, C.; Fredian, T.; Stillerman, J.

2008-01-01

Recent extensions to MDSplus allow data handling in long discharges and provide a real-time data access and communication layer. The real-time data access layer is an additional component of MDSplus: it is possible to use the traditional MDSplus API during normal operation, and to select a subset of data items to be used in real time. Real-time notification is provided by a communication layer using a publish-subscribe pattern. The notification covers processes sharing the same data items even running on different machines, thus allowing the implementation of distributed control systems. The real-time data access layer has been developed for Windows, Linux, and VxWorks; it is currently being ported to Linux RTAI. In order to quantify the fingerprint of the presented system, the performance of the real-time access layer approach is compared with that of an ad hoc, manually optimized program in a sample real-time application

A Real-Time Systems Symposium Preprint.

Science.gov (United States)

1983-09-01

Real - Time Systems Symposium Preprint Interim Tech...estimate of the occurence of the error. Unclassii ledSECUqITY CLASSIF’ICA T" NO MI*IA If’ inDI /’rrd erter for~~ble. ’Corrputnqg A REAL - TIME SYSTEMS SYMPOSIUM...ABSTRACT This technical report contains a preprint of a paper accepted for presentation at the REAL - TIME SYSTEMS SYMPOSIUM, Arlington,

Benefits of real-time gas management

International Nuclear Information System (INIS)

Nolty, R.; Dolezalek, D. Jr.

1994-01-01

In today's competitive gas gathering, processing, storage and transportation business environment, the requirements to do business are continually changing. These changes arise from government regulations such as the amendments to the Clean Air Act concerning the environment and FERC Order 636 concerning business practices. Other changes are due to advances in technology such as electronic flow measurement (EFM) and real-time communications capabilities within the gas industry. Gas gathering, processing, storage and transportation companies must be flexible in adapting to these changes to remain competitive. These dynamic requirements can be met with an open, real-time gas management computer information system. Such a system provides flexible services with a variety of software applications. Allocations, nominations management and gas dispatching are examples of applications that are provided on a real-time basis. By providing real-time services, the gas management system enables operations personnel to make timely adjustments within the current accounting period. Benefits realized from implementing a real-time gas management system include reduced unaccountable gas, reduced imbalance penalties, reduced regulatory violations, improved facility operations and better service to customers. These benefits give a company the competitive edge. This article discusses the applications provided, the benefits from implementing a real-time gas management system, and the definition of such a system

Making real-time reactive systems reliable

Science.gov (United States)

Marzullo, Keith; Wood, Mark

1990-01-01

A reactive system is characterized by a control program that interacts with an environment (or controlled program). The control program monitors the environment and reacts to significant events by sending commands to the environment. This structure is quite general. Not only are most embedded real time systems reactive systems, but so are monitoring and debugging systems and distributed application management systems. Since reactive systems are usually long running and may control physical equipment, fault tolerance is vital. The research tries to understand the principal issues of fault tolerance in real time reactive systems and to build tools that allow a programmer to design reliable, real time reactive systems. In order to make real time reactive systems reliable, several issues must be addressed: (1) How can a control program be built to tolerate failures of sensors and actuators. To achieve this, a methodology was developed for transforming a control program that references physical value into one that tolerates sensors that can fail and can return inaccurate values; (2) How can the real time reactive system be built to tolerate failures of the control program. Towards this goal, whether the techniques presented can be extended to real time reactive systems is investigated; and (3) How can the environment be specified in a way that is useful for writing a control program. Towards this goal, whether a system with real time constraints can be expressed as an equivalent system without such constraints is also investigated.

Temperature dependence of nuclear surface properties

International Nuclear Information System (INIS)

Campi, X.; Stringari, S.

1982-01-01

Thermal properties of nuclear surface are investigated in a semi-infinite medium. Explicit analytical expression are given for the temperature dependence of surface thickness, surface energy and surface free energy. In this model the temperature effects depend critically on the nuclear incompressibility and on the shape of the effective mass at the surface. To illustrate the relevance of these effects we made an estimate of the temperature dependence of the fission barrier height. (orig.)

Preparation of carbon-free TEM microgrids by metal sputtering

Energy Technology Data Exchange (ETDEWEB)

Janbroers, S., E-mail: stephan.janbroers@albemarle.com [Albemarle Catalysts B.V., Nieuwendammerkade 1-3, 1030 BE, Amsterdam (Netherlands); Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Kruijff, T.R. de; Xu, Q. [Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Kooyman, P.J. [DelftChemTech, Delft University of Technology, Julianalaan 136, 2628 BL, Delft (Netherlands); Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Zandbergen, H.W. [Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands)

2009-08-15

A new method for preparing carbon-free, temperature-stable Transmission Electron Microscope (TEM) grids is presented. An 80% Au/20% Pd metal film is deposited onto a 'holey' microgrid carbon supported on standard mixed-mesh Au TEM grids. Subsequently, the carbon film is selectively removed using plasma cleaning. In this way, an all-metal TEM film is made containing the 'same' microgrid as the original carbon film. Although electron transparency of the foil is reduced significantly, the open areas for TEM inspection of material over these areas are maintained. The metal foil can be prepared with various thicknesses and ensures good electrical conductivity. The new Au/Pd grids are stable to at least 775 K under vacuum conditions.

Regulation of ETG turbulence by TEM driven zonal flows

Science.gov (United States)

Asahi, Yuuichi; Ishizawa, Akihiro; Watanabe, Tomohiko; Tsutsui, Hiroaki; Tsuji-Iio, Shunji

2013-10-01

Anomalous heat transport driven by electron temperature gradient (ETG) turbulence is investigated by means of gyrokinetic simulations. It is found that the ETG turbulence can be suppressed by zonal flows driven by trapped electron modes (TEMs). The TEMs appear in a statistically steady state of ETG turbulence and generate zonal flows, while its growth rate is much smaller than those of ETGs. The TEM-driven zonal flows with lower radial wave numbers are more strongly generated than those driven by ETG modes, because of the higher zonal flow response to a density source term. An ExB shearing rate of the TEM-driven zonal flows is strong enough to suppress the long-wavelength ETG modes which make the main contribution to the turbulent transport.

TEM Characterization of Helium Bubbles in T91 and MNHS Steels Implanted with 200 keV He Ions at Different Temperatures

International Nuclear Information System (INIS)

Wang Ji; Gao Xing; Wang Zhi-Guang; Wei Kong-Fang; Yao Cun-Feng; Cui Ming-Huan; Sun Jian-Rong; Li Bing-Sheng; Pang Li-Long; Zhu Ya-Bin; Luo Peng; Chang Hai-Long; Zhang Hong-Peng; Zhu Hui-Ping; Wang Dong; Du Yang-Yang; Xie Er-Qing

2015-01-01

Modified novel high silicon steel (MNHS, a newly developed reduced-activation martensitic alloy) and commercial alloy T91 are implanted with 200 keV He"2"+ ions to a dose of 5 × 10"2"0 ions/m"2 at 300, 450 and 550°C. Transmission electron microscopy (TEM) is used to characterize the size and morphology of He bubbles. With the increase of the implantation temperature, TEM observations indicate that bubbles increase in size and the proportion of ‘brick shaped’ cuboid bubbles increases while the proportion of polyhedral bubbles decreases in both the steel samples. For the samples implanted at the same temperature, the average size of He bubbles in MNHS is smaller than that in T91. This might be due to the abundance of boundaries and precipitates in MNHS, which provide additional sites for the trapping of He atoms, thus reduce the susceptibility of MNHS to He embrittlement. (paper)

Time-dependent Fracture Behaviour of Polyampholyte Hydrogels

Science.gov (United States)

Sun, Tao Lin; Luo, Feng; Nakajima, Tasuku; Kurokawa, Takayuki; Gong, Jian Ping

Recently, we report that polyampholytes, polymers bearing randomly dispersed cationic and anionic repeat groups, form tough and self-healing hydrogels with excellent multiple mechanical functions. The randomness makes ionic bonds with a wide distribution of strength, via inter and intra chain complexation. As the breaking and reforming of ionic bonds are time dependent, the hydrogels exhibit rate dependent mechanical behaviour. We systematically studied the tearing energy by tearing test with various tearing velocity under different temperature, and the linear viscoelastic behaviour over a wide range of frequency and temperature. Results have shown that the tearing energy markedly increase with the crack velocity and decrease with the measured temperature. In accordance with the prediction of Williams, Landel, and Ferry (WLF) rate-temperature equivalence, a master curve of tearing energy dependence of crack velocity can be well constructed using the same shift factor from the linear viscoelastic data. The scaling relation of tearing energy as a function of crack velocity can be predicted well by the rheological data according to the developed linear fracture mechanics.

Time and temperature dependent breakdown characteristics of ZnS:Mn films obtained by rf-magnetron sputtering

Science.gov (United States)

Zhigal'Skii, A. A.; Mukhachev, V. A.; Troyan, P. E.

1994-04-01

Breakdown delay times (tdel) for films of managanese-doped zinc sulfide (ZnS:Mn) were measured in the range 10-6-10-1 s. The maximum value was tdel=10-3-10-2 s. The electrical strength (Ebr) was found to increase as the voltage pulse duration was reduced, the more so the thinner the ZnS:Mn film. The temperature dependence of Ebr exhibited a weak reduction in Ebr as the temperature was raised to roughly 80°C and a sharp reduction in Ebr for T>130°C. A maximum in Ebr was observed at T≈130°C which is presumably explained by a structural modification of the ZnS:Mn film. The experimental results obtained are explained in terms of a combined electronic and thermal breakdown mechanism.

Space Weather and Real-Time Monitoring

Directory of Open Access Journals (Sweden)

S Watari

2009-04-01

Full Text Available Recent advance of information and communications technology enables to collect a large amount of ground-based and space-based observation data in real-time. The real-time data realize nowcast of space weather. This paper reports a history of space weather by the International Space Environment Service (ISES in association with the International Geophysical Year (IGY and importance of real-time monitoring in space weather.

Research Directions in Real-Time Systems.

Science.gov (United States)

1996-09-01

This report summarizes a survey of published research in real time systems . Material is presented that provides an overview of the topic, focusing on...communications protocols and scheduling techniques. It is noted that real - time systems deserve special attention separate from other areas because of...formal tools for design and analysis of real - time systems . The early work on applications as well as notable theoretical advances are summarized

FPGA-based Fused Smart Sensor for Real-Time Plant-Transpiration Dynamic Estimation

Directory of Open Access Journals (Sweden)

Irineo Torres-Pacheco

2010-09-01

Full Text Available Plant transpiration is considered one of the most important physiological functions because it constitutes the plants evolving adaptation to exchange moisture with a dry atmosphere which can dehydrate or eventually kill the plant. Due to the importance of transpiration, accurate measurement methods are required; therefore, a smart sensor that fuses five primary sensors is proposed which can measure air temperature, leaf temperature, air relative humidity, plant out relative humidity and ambient light. A field programmable gate array based unit is used to perform signal processing algorithms as average decimation and infinite impulse response filters to the primary sensor readings in order to reduce the signal noise and improve its quality. Once the primary sensor readings are filtered, transpiration dynamics such as: transpiration, stomatal conductance, leaf-air-temperature-difference and vapor pressure deficit are calculated in real time by the smart sensor. This permits the user to observe different primary and calculated measurements at the same time and the relationship between these which is very useful in precision agriculture in the detection of abnormal conditions. Finally, transpiration related stress conditions can be detected in real time because of the use of online processing and embedded communications capabilities.

FPGA-based Fused Smart Sensor for Real-Time Plant-Transpiration Dynamic Estimation

Science.gov (United States)

Millan-Almaraz, Jesus Roberto; de Jesus Romero-Troncoso, Rene; Guevara-Gonzalez, Ramon Gerardo; Contreras-Medina, Luis Miguel; Carrillo-Serrano, Roberto Valentin; Osornio-Rios, Roque Alfredo; Duarte-Galvan, Carlos; Rios-Alcaraz, Miguel Angel; Torres-Pacheco, Irineo

2010-01-01

Plant transpiration is considered one of the most important physiological functions because it constitutes the plants evolving adaptation to exchange moisture with a dry atmosphere which can dehydrate or eventually kill the plant. Due to the importance of transpiration, accurate measurement methods are required; therefore, a smart sensor that fuses five primary sensors is proposed which can measure air temperature, leaf temperature, air relative humidity, plant out relative humidity and ambient light. A field programmable gate array based unit is used to perform signal processing algorithms as average decimation and infinite impulse response filters to the primary sensor readings in order to reduce the signal noise and improve its quality. Once the primary sensor readings are filtered, transpiration dynamics such as: transpiration, stomatal conductance, leaf-air-temperature-difference and vapor pressure deficit are calculated in real time by the smart sensor. This permits the user to observe different primary and calculated measurements at the same time and the relationship between these which is very useful in precision agriculture in the detection of abnormal conditions. Finally, transpiration related stress conditions can be detected in real time because of the use of online processing and embedded communications capabilities. PMID:22163656

Transition from Arrhenius to non-Arrhenius temperature dependence of structural relaxation time in glass-forming liquids: continuous versus discontinuous scenario.

Science.gov (United States)

Popova, V A; Surovtsev, N V

2014-09-01

The temperature dependences of α relaxation time τ(α)(T) of three glass-forming liquids (salol, o-terphenyl, and α-picoline) were investigated by a depolarized light scattering technique. A detailed description of τ(α)(T) near T(A), the temperature of the transition from the Arrhenius law at high temperatures to a non-Arrhenius behavior of τ(α)(T) at lower temperatures, was done. It was found that this transition is quite sharp. If the transition is described as switching from the Arrhenius law to the Vogel-Fulcher-Tammann law, it occurs within the temperature range of about 15 K or less. Most of the known expressions for τ(α)(T) cannot describe this sharp transition. Our analysis revealed that this transition can be described either as a discontinuous transition in the spirit of the frustration-limited domain theory [D. Kivelson, G. Tarjus, X. Zhao, and S. A. Kivelson, Phys. Rev. E 53, 751 (1996)], implying a phase transition, or by a phenomenological expression recently suggested [B. Schmidtke, N. Petzold, R. Kahlau, M. Hofmann, and E. A. Rössler, Phys. Rev. E 86, 041507 (2012)], where the activation energy includes the term depending exponentially on temperature.

Real-time GIS data model and sensor web service platform for environmental data management.

Science.gov (United States)

Gong, Jianya; Geng, Jing; Chen, Zeqiang

2015-01-09

Effective environmental data management is meaningful for human health. In the past, environmental data management involved developing a specific environmental data management system, but this method often lacks real-time data retrieving and sharing/interoperating capability. With the development of information technology, a Geospatial Service Web method is proposed that can be employed for environmental data management. The purpose of this study is to determine a method to realize environmental data management under the Geospatial Service Web framework. A real-time GIS (Geographic Information System) data model and a Sensor Web service platform to realize environmental data management under the Geospatial Service Web framework are proposed in this study. The real-time GIS data model manages real-time data. The Sensor Web service platform is applied to support the realization of the real-time GIS data model based on the Sensor Web technologies. To support the realization of the proposed real-time GIS data model, a Sensor Web service platform is implemented. Real-time environmental data, such as meteorological data, air quality data, soil moisture data, soil temperature data, and landslide data, are managed in the Sensor Web service platform. In addition, two use cases of real-time air quality monitoring and real-time soil moisture monitoring based on the real-time GIS data model in the Sensor Web service platform are realized and demonstrated. The total time efficiency of the two experiments is 3.7 s and 9.2 s. The experimental results show that the method integrating real-time GIS data model and Sensor Web Service Platform is an effective way to manage environmental data under the Geospatial Service Web framework.

XpertTrack: Precision Autonomous Measuring Device Developed for Real Time Shipments Tracker

Directory of Open Access Journals (Sweden)

Liviu Viman

2016-03-01

Full Text Available This paper proposes a software and hardware solution for real time condition monitoring applications. The proposed device, called XpertTrack, exchanges data through the GPRS protocol over a GSM network and monitories temperature and vibrations of critical merchandise during commercial shipments anywhere on the globe. Another feature of this real time tracker is to provide GPS and GSM positioning with a precision of 10 m or less. In order to interpret the condition of the merchandise, the data acquisition, analysis and visualization are done with 0.1 °C accuracy for the temperature sensor, and 10 levels of shock sensitivity for the acceleration sensor. In addition to this, the architecture allows increasing the number and the types of sensors, so that companies can use this flexible solution to monitor a large percentage of their fleet.

XpertTrack: Precision Autonomous Measuring Device Developed for Real Time Shipments Tracker

Science.gov (United States)

Viman, Liviu; Daraban, Mihai; Fizesan, Raul; Iuonas, Mircea

2016-01-01

This paper proposes a software and hardware solution for real time condition monitoring applications. The proposed device, called XpertTrack, exchanges data through the GPRS protocol over a GSM network and monitories temperature and vibrations of critical merchandise during commercial shipments anywhere on the globe. Another feature of this real time tracker is to provide GPS and GSM positioning with a precision of 10 m or less. In order to interpret the condition of the merchandise, the data acquisition, analysis and visualization are done with 0.1 °C accuracy for the temperature sensor, and 10 levels of shock sensitivity for the acceleration sensor. In addition to this, the architecture allows increasing the number and the types of sensors, so that companies can use this flexible solution to monitor a large percentage of their fleet. PMID:26978360

Time-dependent reliability sensitivity analysis of motion mechanisms

International Nuclear Information System (INIS)

Wei, Pengfei; Song, Jingwen; Lu, Zhenzhou; Yue, Zhufeng

2016-01-01

Reliability sensitivity analysis aims at identifying the source of structure/mechanism failure, and quantifying the effects of each random source or their distribution parameters on failure probability or reliability. In this paper, the time-dependent parametric reliability sensitivity (PRS) analysis as well as the global reliability sensitivity (GRS) analysis is introduced for the motion mechanisms. The PRS indices are defined as the partial derivatives of the time-dependent reliability w.r.t. the distribution parameters of each random input variable, and they quantify the effect of the small change of each distribution parameter on the time-dependent reliability. The GRS indices are defined for quantifying the individual, interaction and total contributions of the uncertainty in each random input variable to the time-dependent reliability. The envelope function method combined with the first order approximation of the motion error function is introduced for efficiently estimating the time-dependent PRS and GRS indices. Both the time-dependent PRS and GRS analysis techniques can be especially useful for reliability-based design. This significance of the proposed methods as well as the effectiveness of the envelope function method for estimating the time-dependent PRS and GRS indices are demonstrated with a four-bar mechanism and a car rack-and-pinion steering linkage. - Highlights: • Time-dependent parametric reliability sensitivity analysis is presented. • Time-dependent global reliability sensitivity analysis is presented for mechanisms. • The proposed method is especially useful for enhancing the kinematic reliability. • An envelope method is introduced for efficiently implementing the proposed methods. • The proposed method is demonstrated by two real planar mechanisms.

Temperature dependence of acceptor-hole recombination in germanium

International Nuclear Information System (INIS)

Darken, L.S.; Jellison, G.E. Jr.

1989-01-01

The recombination kinetics of several centers (Zn - , Cu - , B - , CuH - 2 , CuH - x , Zn = , Cu = , and CuH = x ) in high-purity Ge have been measured as a function of temperature from 8 to 160 K by transient capacitance techniques and are significantly faster than expected from cascade theory. The cascade theory also gives the wrong temperature dependence, and the wrong z dependence. Instead, the data are generally fit by the expression N v /4pτ c congruent kT/h (p and τ c are, respectively, the free-hole concentration in the sample and the experimental mean capture time for a center)

Nonperturbative calculation of the shear viscosity in hot $\\phi^{4}$ theory in real time

CERN Document Server

Wang, E; Wang, Enke; Heinz, Ulrich

1999-01-01

Starting from the Kubo formula we calculate the shear viscosity in hot phi**4 theory nonperturbatively by resumming ladders with a real-time version of the Bethe-Salpeter equation at finite temperature. In the weak coupling limit, the generalized Fluctuation-Dissipation Theorem is shown to decouple the Bethe-Salpeter equations for the different real-time components of the 4-point function. The resulting scalar integral equation is identical with the one obtained by Jeon using diagrammatic ``cutting rules'' in the Imaginary Time Formalism.

Time-dependent perturbations in two-dimensional string black holes

CERN Document Server

Diamandis, G A; Maintas, X N; Mavromatos, Nikolaos E

1992-01-01

We discuss time-dependent perturbations (induced by matter fields) of a black-hole background in tree-level two-dimensional string theory. We analyse the linearized case and show the possibility of having black-hole solutions with time-dependent horizons. The latter exist only in the presence of time-dependent `tachyon' matter fields, which constitute the only propagating degrees of freedom in two-dimensional string theory. For real tachyon field configurations it is not possible to obtain solutions with horizons shrinking to a point. On the other hand, such a possibility seems to be realized in the case of string black-hole models formulated on higher world-sheet genera. We connect this latter result with black hole evaporation/decay at a quantum level.}

Automated real time constant-specificity surveillance for disease outbreaks

Directory of Open Access Journals (Sweden)

Brownstein John S

2007-06-01

Full Text Available Abstract Background For real time surveillance, detection of abnormal disease patterns is based on a difference between patterns observed, and those predicted by models of historical data. The usefulness of outbreak detection strategies depends on their specificity; the false alarm rate affects the interpretation of alarms. Results We evaluate the specificity of five traditional models: autoregressive, Serfling, trimmed seasonal, wavelet-based, and generalized linear. We apply each to 12 years of emergency department visits for respiratory infection syndromes at a pediatric hospital, finding that the specificity of the five models was almost always a non-constant function of the day of the week, month, and year of the study (p Conclusion Modeling the variance of visit patterns enables real-time detection with known, constant specificity at all times. With constant specificity, public health practitioners can better interpret the alarms and better evaluate the cost-effectiveness of surveillance systems.

Communication: Time-dependent optimized coupled-cluster method for multielectron dynamics

Science.gov (United States)

Sato, Takeshi; Pathak, Himadri; Orimo, Yuki; Ishikawa, Kenichi L.

2018-02-01

Time-dependent coupled-cluster method with time-varying orbital functions, called time-dependent optimized coupled-cluster (TD-OCC) method, is formulated for multielectron dynamics in an intense laser field. We have successfully derived the equations of motion for CC amplitudes and orthonormal orbital functions based on the real action functional, and implemented the method including double excitations (TD-OCCD) and double and triple excitations (TD-OCCDT) within the optimized active orbitals. The present method is size extensive and gauge invariant, a polynomial cost-scaling alternative to the time-dependent multiconfiguration self-consistent-field method. The first application of the TD-OCC method of intense-laser driven correlated electron dynamics in Ar atom is reported.

REAL-TIME ASSESSMENT OF MICROWAVE ABLATION EFFICACY BY NIR SPECTROSCOPIC TECHNIQUE

Directory of Open Access Journals (Sweden)

JINZHE ZHAO

2014-01-01

Full Text Available Microwave ablation (MWA status monitoring in real time plays a key role in assessment of therapeutic effectiveness. As a novel real-time assessment method, near infrared spectroscopy (NIRs was used to evaluate the ablation efficacy. MWA experiments were carried out on in vitro porcine livers. An optical measurement system for biological tissue is developed by our lab to monitor reduced scattering coefficient $(\\mu_{s}^{'}$ at 690 nm of the coagulation zones. It is noted that $\\mu_{s}^{'}$ of liver tissue, which increases as the liver tissue being ablated, is clearly related with the coagulation status. $\\mu_{s}^{'}$ of normal tissue and coagulated tissue is 3–5 and 17–19 cm-1, respectively. Continuous changes of $\\mu_{s}^{'}$ demonstrate that optical parameter can be used as an efficacy evaluation factor because it essentially indicates the degree of thermal damage. Compared with temperature, optical parameter is more sensitive and accurate, which is promising for real-time therapeutic efficacy assessment in MWA.

Real-Time MENTAT programming language and architecture

Science.gov (United States)

Grimshaw, Andrew S.; Silberman, Ami; Liu, Jane W. S.

1989-01-01

Real-time MENTAT, a programming environment designed to simplify the task of programming real-time applications in distributed and parallel environments, is described. It is based on the same data-driven computation model and object-oriented programming paradigm as MENTAT. It provides an easy-to-use mechanism to exploit parallelism, language constructs for the expression and enforcement of timing constraints, and run-time support for scheduling and exciting real-time programs. The real-time MENTAT programming language is an extended C++. The extensions are added to facilitate automatic detection of data flow and generation of data flow graphs, to express the timing constraints of individual granules of computation, and to provide scheduling directives for the runtime system. A high-level view of the real-time MENTAT system architecture and programming language constructs is provided.

Real Time Conference 2016 Overview

Science.gov (United States)

Luchetta, Adriano

2017-06-01

This is a special issue of the IEEE Transactions on Nuclear Science containing papers from the invited, oral, and poster presentation of the 20th Real Time Conference (RT2016). The conference was held June 6-10, 2016, at Centro Congressi Padova “A. Luciani,” Padova, Italy, and was organized by Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA) and the Istituto Nazionale di Fisica Nucleare. The Real Time Conference is multidisciplinary and focuses on the latest developments in real-time techniques in high-energy physics, nuclear physics, astrophysics and astroparticle physics, nuclear fusion, medical physics, space instrumentation, nuclear power instrumentation, general radiation instrumentation, and real-time security and safety. Taking place every second year, it is sponsored by the Computer Application in Nuclear and Plasma Sciences technical committee of the IEEE Nuclear and Plasma Sciences Society. RT2016 attracted more than 240 registrants, with a large proportion of young researchers and engineers. It had an attendance of 67 students from many countries.

Temperature dependence of Brewster's angle.

Science.gov (United States)

Guo, Wei

2018-01-01

In this work, a dielectric at a finite temperature is modeled as an ensemble of identical atoms moving randomly around where they are trapped. Light reflection from the dielectric is then discussed in terms of atomic radiation. Specific calculation demonstrates that because of the atoms' thermal motion, Brewster's angle is, in principle, temperature-dependent, and the dependence is weak in the low-temperature limit. What is also found is that the Brewster's angle is nothing but a result of destructive superposition of electromagnetic radiation from the atoms.

Run-time middleware to support real-time system scenarios

NARCIS (Netherlands)

Goossens, K.; Koedam, M.; Sinha, S.; Nelson, A.; Geilen, M.

2015-01-01

Systems on Chip (SOC) are powerful multiprocessor systems capable of running multiple independent applications, often with both real-time and non-real-time requirements. Scenarios exist at two levels: first, combinations of independent applications, and second, different states of a single

Temperature dependence of plastic scintillators

Science.gov (United States)

Peralta, L.

2018-03-01

Plastic scintillator detectors have been studied as dosimeters, since they provide a cost-effective alternative to conventional ionization chambers. Several articles have reported undesired response dependencies on beam energy and temperature, which provides the motivation to determine appropriate correction factors. In this work, we studied the light yield temperature dependency of four plastic scintillators, BCF-10, BCF-60, BC-404, RP-200A and two clear fibers, BCF-98 and SK-80. Measurements were made using a 50 kVp X-ray beam to produce the scintillation and/or radioluminescence signal. The 0 to 40 °C temperature range was scanned for each scintillator, and temperature coefficients were obtained.

Advanced real-time manipulation of video streams

CERN Document Server

Herling, Jan

2014-01-01

Diminished Reality is a new fascinating technology that removes real-world content from live video streams. This sensational live video manipulation actually removes real objects and generates a coherent video stream in real-time. Viewers cannot detect modified content. Existing approaches are restricted to moving objects and static or almost static cameras and do not allow real-time manipulation of video content. Jan Herling presents a new and innovative approach for real-time object removal with arbitrary camera movements.

Real time observables for the quark-gluon plasma from the lattice

International Nuclear Information System (INIS)

Schaefer, Christian

2014-01-01

In this thesis we studied real time quantities and processes of the quark-gluon plasma. We employed the fundamental theory of QCD allowing for predictions from first principles. Treating QCD on the lattice enabled us to access non-perturbative regimes and for the very first time we computed a hydrodynamic transport coefficient without having to resort to maximum entropy methods or functional input. Furthermore we established a semi-classical formulation of QCD that we applied to investigate the effects of dynamic fermions as well as of using the correct colour group of QCD, SU(3), on the isotropization process of the quark-gluon plasma. In this work we have calculated the second order hydrodynamic transport coefficient κ for the Yang-Mills plasma using lattice perturbation theory and Monte Carlo simulations. From calculations both in strong and weak coupling limits, we expect a temperature dependence of κ∝T 2 . In the investigated temperature range 2T c c our data is consistent with this expectation. Our quantitative result for the transport coefficient is κ=0.36(15)T 2 . Within the error bars, it agrees with predictions from AdS/CFT correspondence rescaled to the field content of Yang-Mills theory as well as leading order perturbation theory. An investigation of the isotropization process via a chromo-Weibel instability is impeded by the fact that the pre-equilibrium phase in a heavy-ion collision constitutes a system far from equilibrium. Furthermore isotropization is a dynamic process and its investigation requires a treatment in real time. For this reason we established a semiclassical lattice approach to QCD facilitating a first principle description of real time processes far from equilibrium. In the investigation of the isotropization process in heavy-ion collisions, we borrowed initial conditions from the colour-glass-condensate effective theory. Studying the pure bosonic dynamics with colour group SU(3) in a static box, we found evidence for the

Real-Time Implementation of Islanded Microgrid for Remote Areas

Directory of Open Access Journals (Sweden)

Monika Jain

2016-01-01

Full Text Available Islanding is a condition in which a microgrid or a portion of power grid, consisting of distributed generation (DG sources, converter, and load, gets disconnected from the utility grid. Under this condition the DG sources in a microgrid must switch to a voltage control mode, in order to provide constant voltage to local loads. In grid connected mode, the microgrid works as current controller and injects power to the main grid, depending on the power generation and local load with suitable market policies. Providing constant voltage at a stable frequency with proper synchronization amongst each DG in a microgrid is a challenge. The complexity of such grid requires careful study and analysis before actual implementation. These challenges of microgrid are addressed using real time OPAL-RT simulation technology. Thus the paper describes an islanded microgrid with master slave controller for power balance, voltage/frequency regulation, and synchronization. Based on an advanced real-time platform named Real-Time Laboratory (RT-LAB, the impacts of the micro sources, load, and converters in an islanded microgrid is studied in this paper. The effectiveness of the proposed controller is analyzed through experimental results under balanced/unbalanced nonlinear loads condition.

Time-dependent density-functional theory in massively parallel computer architectures: the OCTOPUS project.

Science.gov (United States)

Andrade, Xavier; Alberdi-Rodriguez, Joseba; Strubbe, David A; Oliveira, Micael J T; Nogueira, Fernando; Castro, Alberto; Muguerza, Javier; Arruabarrena, Agustin; Louie, Steven G; Aspuru-Guzik, Alán; Rubio, Angel; Marques, Miguel A L

2012-06-13

Octopus is a general-purpose density-functional theory (DFT) code, with a particular emphasis on the time-dependent version of DFT (TDDFT). In this paper we present the ongoing efforts to achieve the parallelization of octopus. We focus on the real-time variant of TDDFT, where the time-dependent Kohn-Sham equations are directly propagated in time. This approach has great potential for execution in massively parallel systems such as modern supercomputers with thousands of processors and graphics processing units (GPUs). For harvesting the potential of conventional supercomputers, the main strategy is a multi-level parallelization scheme that combines the inherent scalability of real-time TDDFT with a real-space grid domain-partitioning approach. A scalable Poisson solver is critical for the efficiency of this scheme. For GPUs, we show how using blocks of Kohn-Sham states provides the required level of data parallelism and that this strategy is also applicable for code optimization on standard processors. Our results show that real-time TDDFT, as implemented in octopus, can be the method of choice for studying the excited states of large molecular systems in modern parallel architectures.

Time-dependent density-functional theory in massively parallel computer architectures: the octopus project

Science.gov (United States)

Andrade, Xavier; Alberdi-Rodriguez, Joseba; Strubbe, David A.; Oliveira, Micael J. T.; Nogueira, Fernando; Castro, Alberto; Muguerza, Javier; Arruabarrena, Agustin; Louie, Steven G.; Aspuru-Guzik, Alán; Rubio, Angel; Marques, Miguel A. L.

2012-06-01

Octopus is a general-purpose density-functional theory (DFT) code, with a particular emphasis on the time-dependent version of DFT (TDDFT). In this paper we present the ongoing efforts to achieve the parallelization of octopus. We focus on the real-time variant of TDDFT, where the time-dependent Kohn-Sham equations are directly propagated in time. This approach has great potential for execution in massively parallel systems such as modern supercomputers with thousands of processors and graphics processing units (GPUs). For harvesting the potential of conventional supercomputers, the main strategy is a multi-level parallelization scheme that combines the inherent scalability of real-time TDDFT with a real-space grid domain-partitioning approach. A scalable Poisson solver is critical for the efficiency of this scheme. For GPUs, we show how using blocks of Kohn-Sham states provides the required level of data parallelism and that this strategy is also applicable for code optimization on standard processors. Our results show that real-time TDDFT, as implemented in octopus, can be the method of choice for studying the excited states of large molecular systems in modern parallel architectures.

Time-dependent density-functional theory in massively parallel computer architectures: the octopus project

International Nuclear Information System (INIS)

Andrade, Xavier; Aspuru-Guzik, Alán; Alberdi-Rodriguez, Joseba; Rubio, Angel; Strubbe, David A; Louie, Steven G; Oliveira, Micael J T; Nogueira, Fernando; Castro, Alberto; Muguerza, Javier; Arruabarrena, Agustin; Marques, Miguel A L

2012-01-01

Octopus is a general-purpose density-functional theory (DFT) code, with a particular emphasis on the time-dependent version of DFT (TDDFT). In this paper we present the ongoing efforts to achieve the parallelization of octopus. We focus on the real-time variant of TDDFT, where the time-dependent Kohn-Sham equations are directly propagated in time. This approach has great potential for execution in massively parallel systems such as modern supercomputers with thousands of processors and graphics processing units (GPUs). For harvesting the potential of conventional supercomputers, the main strategy is a multi-level parallelization scheme that combines the inherent scalability of real-time TDDFT with a real-space grid domain-partitioning approach. A scalable Poisson solver is critical for the efficiency of this scheme. For GPUs, we show how using blocks of Kohn-Sham states provides the required level of data parallelism and that this strategy is also applicable for code optimization on standard processors. Our results show that real-time TDDFT, as implemented in octopus, can be the method of choice for studying the excited states of large molecular systems in modern parallel architectures. (topical review)

VES/TEM 1D joint inversion by using Controlled Random Search (CRS) algorithm

Science.gov (United States)

Bortolozo, Cassiano Antonio; Porsani, Jorge Luís; Santos, Fernando Acácio Monteiro dos; Almeida, Emerson Rodrigo

2015-01-01

Electrical (DC) and Transient Electromagnetic (TEM) soundings are used in a great number of environmental, hydrological, and mining exploration studies. Usually, data interpretation is accomplished by individual 1D models resulting often in ambiguous models. This fact can be explained by the way as the two different methodologies sample the medium beneath surface. Vertical Electrical Sounding (VES) is good in marking resistive structures, while Transient Electromagnetic sounding (TEM) is very sensitive to conductive structures. Another difference is VES is better to detect shallow structures, while TEM soundings can reach deeper layers. A Matlab program for 1D joint inversion of VES and TEM soundings was developed aiming at exploring the best of both methods. The program uses CRS - Controlled Random Search - algorithm for both single and 1D joint inversions. Usually inversion programs use Marquadt type algorithms but for electrical and electromagnetic methods, these algorithms may find a local minimum or not converge. Initially, the algorithm was tested with synthetic data, and then it was used to invert experimental data from two places in Paraná sedimentary basin (Bebedouro and Pirassununga cities), both located in São Paulo State, Brazil. Geoelectric model obtained from VES and TEM data 1D joint inversion is similar to the real geological condition, and ambiguities were minimized. Results with synthetic and real data show that 1D VES/TEM joint inversion better recovers simulated models and shows a great potential in geological studies, especially in hydrogeological studies.

Modeling the temperature dependence of thermophysical properties: Study on the effect of temperature dependence for RFA.

Science.gov (United States)

Watanabe, Hiroki; Kobayashi, Yo; Hashizume, Makoto; Fujie, Masakatsu G

2009-01-01

Radio frequency ablation (RFA) has increasingly been used over the past few years and RFA treatment is minimally invasive for patients. However, it is difficult for operators to control the precise formation of coagulation zones due to inadequate imaging modalities. With this in mind, an ablation system using numerical simulation to analyze the temperature distribution of the organ is needed to overcome this deficiency. The objective of our work is to develop a temperature dependent thermophysical liver model. First, an overview is given of the development of the thermophysical liver model. Second, a simulation to evaluate the effect of temperature dependence of the thermophysical properties of the liver is explained. Finally, the result of the simulation, which indicated that the temperature dependence of thermophysical properties accounts for temperature differences influencing the accuracy of RFA treatment is described.

Time-Dependent Stress Rupture Strength Degradation of Hi-Nicalon Fiber-Reinforced Silicon Carbide Composites at Intermediate Temperatures

Science.gov (United States)

Sullivan, Roy M.

2016-01-01

The stress rupture strength of silicon carbide fiber-reinforced silicon carbide composites with a boron nitride fiber coating decreases with time within the intermediate temperature range of 700 to 950 degree Celsius. Various theories have been proposed to explain the cause of the time-dependent stress rupture strength. The objective of this paper is to investigate the relative significance of the various theories for the time-dependent strength of silicon carbide fiber-reinforced silicon carbide composites. This is achieved through the development of a numerically based progressive failure analysis routine and through the application of the routine to simulate the composite stress rupture tests. The progressive failure routine is a time-marching routine with an iterative loop between a probability of fiber survival equation and a force equilibrium equation within each time step. Failure of the composite is assumed to initiate near a matrix crack and the progression of fiber failures occurs by global load sharing. The probability of survival equation is derived from consideration of the strength of ceramic fibers with randomly occurring and slow growing flaws as well as the mechanical interaction between the fibers and matrix near a matrix crack. The force equilibrium equation follows from the global load sharing presumption. The results of progressive failure analyses of the composite tests suggest that the relationship between time and stress-rupture strength is attributed almost entirely to the slow flaw growth within the fibers. Although other mechanisms may be present, they appear to have only a minor influence on the observed time-dependent behavior.

Maintainability analysis considering time-dependent and time-independent covariates

International Nuclear Information System (INIS)

Barabadi, Abbas; Barabady, Javad; Markeset, Tore

2011-01-01

Traditional parametric methods for assessing maintainability most often only consider time to repair (TTR) as a single explanatory variable. However, to predict availability more precisely for high availability systems, a better model is needed to quantify the effect of operational environment on maintainability. The proportional repair model (PRM), which is developed based on proportional hazard model (PHM), may be used to analyze maintainability in the present of covariates. In the PRM, the effect of covariates is considered to be time independent. However this assumption may not be valid for some situations. The aim of this paper is to develop the Cox regression model and its extension in the presence of time-dependent covariates for determining maintainability. A simple case study is used to demonstrate how the model can be applied in a real case.

A multiplex real-time PCR assay targeting virulence and resistance genes in Salmonella enterica serotype Typhimurium

Directory of Open Access Journals (Sweden)

Brisabois Anne

2011-06-01

Full Text Available Abstract Background Typhimurium is the main serotype of Salmonella enterica subsp. enterica implicated in food-borne diseases worldwide. This study aimed to detect the prevalence of ten markers combined in a macro-array based on multiplex real-time PCR. We targeted characteristic determinants located on pathogenicity islands (SPI-2 to -5, virulence plasmid pSLT and Salmonella genomic island 1 (SGI1 as well as a specific 16S-23S rRNA intergenic spacer sequence of definitive type 104 (DT104. To investigate antimicrobial resistance, the study also targeted the presence of genes involved in sulfonamide (sul1 and beta-lactam (blaTEM resistance. Finally, the intI1 determinant encoding integrase from class 1 integron was also investigated. Results A total of 538 unrelated S. Typhimurium strains isolated between 1999 and 2009 from various sources, including food animals, food products, human and environmental samples were studied. Based on the combined presence or absence of these markers, we distinguished 34 different genotypes, including three major genotypes encountered in 75% of the studied strains, Although SPI determinants were almost always detected, SGI1, intI1, sul1 and blaTEM determinants were found 47%, 52%, 54% and 12% of the time respectively, varying according to isolation source. Low-marker patterns were most often detected in poultry sources whereas full-marker patterns were observed in pig, cattle and human sources. Conclusion The GeneDisc® assay developed in this study madeit easier to explore variability within serotype Typhimurium by analyzing ten relevant gene determinants in a large collection of strains. This real-time multiplex method constitutes a valuable tool for strains characterization on epidemiological purposes.

Archtecture of distributed real-time systems

OpenAIRE

Wing Leung, Cheuk

2013-01-01

CRAFTERS (Constraint and Application Driven Framework for Tailoring Embedded Real-time System) project aims to address the problem of uncertainty and heterogeneity in a distributed system by providing seamless, portable connectivity and middleware. This thesis contributes to the project by investigating the techniques that can be used in a distributed real-time embedded system. The conclusion is that, there is a list of specifications to be meet in order to provide a transparent and real-time...

Development of a versatile TEM specimen holder for the characterization of photocatalytic materials

DEFF Research Database (Denmark)

Cavalca, Filippo; Langhammer, C.; Hansen, Thomas Willum

2011-01-01

conventional TEM analysis on photocatalysts with several in situ TEM techniques including environmental TEM (ETEM), in situ photo activation and localized surface plasmon resonance (LSPR) spectroscopy [3-4]. These experiments are facilitated by the construction of a specimen holder capable of illuminating....../on nanomaterials and thin films. We present results from combined ETEM-LSPR studies of thermally-induced catalytic phenomena and on metal nanoparticle sintering, an important process in catalysis, which we study in situ in both real and model systems by means of indirect nanoplasmonic sensing and ETEM....

Oxidation in ceria infiltrated metal supported SOFCs – A TEM investigation

DEFF Research Database (Denmark)

Knibbe, Ruth; Wang, Hsiang-Jen; Blennow Tullmar, Peter

2013-01-01

electron microscopy (TEM) techniques including energy-dispersive X-ray spectroscopy and electron energy-loss spectroscopy of focus ion beamed TEM samples. The infiltrated CGO is predominately converted into CeFeO3 after high temperature processing, protecting the alloy. A thin layer of Cr-oxide is observed...

High resolution real time capable combustion chamber simulation; Zeitlich hochaufloesende echtzeitfaehige Brennraumsimulation

Energy Technology Data Exchange (ETDEWEB)

Piewek, J. [Volkswagen AG, Wolfsburg (Germany)

2008-07-01

The article describes a zero-dimensional model for the real time capable combustion chamber pressure calculation with analogue pressure sensor output. The closed-loop-operation of an Engine Control Unit is shown at the hardware-in-the-loop-simulator (HiL simulator) for a 4-cylinder common rail diesel engine. The presentation of the model focuses on the simulation of the load variation which does not depend on the injection system and thus the simulated heat release rate. Particular attention is paid to the simulation and the resulting test possibilities regarding to full-variable valve gears. It is shown that black box models consisting in the HiL mean value model for the aspirated gas mass, the exhaust gas temperature after the outlet valve and the mean indicated pressure can be replaced by calculations from the high-resolution combustion chamber model. (orig.)

Solving Algebraic Riccati Equation Real Time for Integrated Vehicle Dynamics Control

NARCIS (Netherlands)

Kunnappillil Madhusudhanan, A; Corno, M.; Bonsen, B.; Holweg, E.

2012-01-01

In this paper we present a comparison study of different computational methods to implement State Dependent Riccati Equation (SDRE) based control in real time for a vehicle dynamics control application. Vehicles are mechatronic systems with nonlinear dynamics. One of the promising nonlinear control

The real-time price elasticity of electricity

NARCIS (Netherlands)

Lijesen, M.G.

2007-01-01

The real-time price elasticity of electricity contains important information on the demand response of consumers to the volatility of peak prices. Despite the importance, empirical estimates of the real-time elasticity are hardly available. This paper provides a quantification of the real-time

Liquid-filled ionization chamber temperature dependence

Energy Technology Data Exchange (ETDEWEB)

Franco, L. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain)]. E-mail: luciaff@usc.es; Gomez, F. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain); Iglesias, A. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain); Pardo, J. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain); Pazos, A. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain); Pena, J. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain); Zapata, M. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain)

2006-05-10

Temperature and pressure corrections of the read-out signal of ionization chambers have a crucial importance in order to perform high-precision absolute dose measurements. In the present work the temperature and pressure dependences of a sealed liquid isooctane filled ionization chamber (previously developed by the authors) for radiotherapy applications have been studied. We have analyzed the thermal response of the liquid ionization chamber in a {approx}20 deg. C interval around room temperature. The temperature dependence of the signal can be considered linear, with a slope that depends on the chamber collection electric field. For example, a relative signal slope of 0.27x10{sup -2}K{sup -1} for an operation electric field of 1.67x10{sup 6}Vm{sup -1} has been measured in our detector. On the other hand, ambient pressure dependence has been found negligible, as expected for liquid-filled chambers. The thermal dependence of the liquid ionization chamber signal can be parametrized within the Onsager theory on initial recombination. Considering that changes with temperature of the detector response are due to variations in the free ion yield, a parametrization of this dependence has been obtained. There is a good agreement between the experimental data and the theoretical model from the Onsager framework.

Neoclassical and gyrokinetic analysis of time-dependent helium transport experiments on MAST

International Nuclear Information System (INIS)

Henderson, S.S.; O'Mullane, M.; Summers, H.P.; Garzotti, L.; Casson, F.J.; Dickinson, D.; Fox, M.F.J.; Patel, A.; Roach, C.M.; Valovič, M.

2014-01-01

Time-dependent helium gas puff experiments have been performed on the Mega Ampère Spherical Tokamak (MAST) during a two point plasma current scan in L-mode and a confinement scan at 900 kA. An evaluation of the He II (n = 4 → 3) spectrum line induced by charge exchange suggests anomalous rates of diffusion and inward convection in the outer regions of both L-mode plasmas. Similar rates of diffusion are found in the H-mode plasma, however these rates are consistent with neoclassical predictions. The anomalous inward pinch found in the core of L-mode plasmas is also not apparent in the H-mode core. Linear gyrokinetic simulations of one flux surface in L-mode using the GS2 and GKW codes find that equilibrium flow shear is sufficient to stabilize ITG modes, consistent with beam emission spectroscopy (BES) observations, and suggest that collisionless TEMs may dominate the anomalous helium particle transport. A quasilinear estimate of the dimensionless peaking factor associated with TEMs is in good agreement with experiment. Collisionless TEMs are more stable in H-mode because the electron density gradient is flatter. The steepness of this gradient is therefore pivotal in determining the inward neoclassical particle pinch and the particle flux associated with TEM turbulence. (paper)

Development of real-time on-line vibration testing system for seismic experiments

International Nuclear Information System (INIS)

Horiuchi, T.; Nakagawa, M.; Kametani, M.

1993-01-01

An on-line vibration testing method is being developed for seismic experiments. This method combines computer simulation and an actuator for vibration testing of structures. A real-time, on-line testing system was developed to improve the method. In the system, the timing of the vibration testing and the computer simulation are the same. This allows time-dependent reaction forces, such as damping force, to be immediately considered in the computer simulation. The real-time system has many requirements, such as complicated matrix calculations within a small time step, and communication with outer devices like sensors and actuators through A/D and D/A converters. These functions arc accomplished by using a newly-developed, real-time controller that employs a parallel processing technique. A small structural model is used to demonstrate the system. The reliability and applicability of the system for seismic experiments can be demonstrated by comparing the results of the system and a shaking table, which are in almost agreement. (author)

Implementing Run-Time Evaluation of Distributed Timing Constraints in a Real-Time Environment

DEFF Research Database (Denmark)

Kristensen, C. H.; Drejer, N.

1994-01-01

In this paper we describe a solution to the problem of implementing run-time evaluation of timing constraints in distributed real-time environments......In this paper we describe a solution to the problem of implementing run-time evaluation of timing constraints in distributed real-time environments...

REAL TIME SYSTEM OPERATIONS 2006-2007

Energy Technology Data Exchange (ETDEWEB)

Eto, Joseph H.; Parashar, Manu; Lewis, Nancy Jo

2008-08-15

The Real Time System Operations (RTSO) 2006-2007 project focused on two parallel technical tasks: (1) Real-Time Applications of Phasors for Monitoring, Alarming and Control; and (2) Real-Time Voltage Security Assessment (RTVSA) Prototype Tool. The overall goal of the phasor applications project was to accelerate adoption and foster greater use of new, more accurate, time-synchronized phasor measurements by conducting research and prototyping applications on California ISO's phasor platform - Real-Time Dynamics Monitoring System (RTDMS) -- that provide previously unavailable information on the dynamic stability of the grid. Feasibility assessment studies were conducted on potential application of this technology for small-signal stability monitoring, validating/improving existing stability nomograms, conducting frequency response analysis, and obtaining real-time sensitivity information on key metrics to assess grid stress. Based on study findings, prototype applications for real-time visualization and alarming, small-signal stability monitoring, measurement based sensitivity analysis and frequency response assessment were developed, factory- and field-tested at the California ISO and at BPA. The goal of the RTVSA project was to provide California ISO with a prototype voltage security assessment tool that runs in real time within California ISO?s new reliability and congestion management system. CERTS conducted a technical assessment of appropriate algorithms, developed a prototype incorporating state-of-art algorithms (such as the continuation power flow, direct method, boundary orbiting method, and hyperplanes) into a framework most suitable for an operations environment. Based on study findings, a functional specification was prepared, which the California ISO has since used to procure a production-quality tool that is now a part of a suite of advanced computational tools that is used by California ISO for reliability and congestion management.

A study of real-time content marketing : formulating real-time content marketing based on content, search and social media

OpenAIRE

Nguyen, Thi Kim Duyen

2015-01-01

The primary objective of this research is to understand profoundly the new concept of content marketing – real-time content marketing on the aspect of the digital marketing experts. Particularly, the research will focus on the real-time content marketing theories and how to build real-time content marketing strategy based on content, search and social media. It also finds out how marketers measure and keep track of conversion rates of their real-time content marketing plan. Practically, th...

Meteorological data assimilation for real-time emergency response

International Nuclear Information System (INIS)

Sugiyama, G.; Chan, S.T.

1996-11-01

The US Department of Energy's Atmospheric Release Advisory Capability (ARAC) provides real-time dose assessments of airborne pollutant releases. Diverse data assimilation techniques are required to meet the needs of a new generation of ARAC models and to take advantage of the rapidly expanding availability of meteorological data. We are developing a hierarchy of algorithms to provide gridded meteorological fields which can be used to drive dispersion codes or to provide initial fields for mesoscale models. Data to be processed include winds, temperature, moisture, and turbulence

In-situ TEM investigations of graphic-epitaxy and small particles

Science.gov (United States)

Heinemann, K.

1983-01-01

Palladium was deposited inside a controlled-vacuum specimen chamber of a transmission electron microscope (TEM) onto MgO and alpha-alumina substrate surfaces. Annealing and various effects of gas exposure of the particulate Pd deposits were studied in-situ by high resolution TEM and electron diffraction. Whereas substrate temperatures of 500 C or annealing of room temperature (RT) deposits to 500 C were needed to obtain epitaxy on sapphire, RT deposits on MgO were perfectly epitaxial. For Pd/MgO a lattice expansion of 2 to 4% was noted; the highest values of expansion were found for the smallest particles. The lattice expansion of small Pd particles on alumina substrates was less than 1%. Long-time RT exposure of Pd/MgO in a vacuum yielded some moblity and coalescence events, but notably fewer than for Pd on sapphire. Exposure to air or oxygen greatly enhanced the particle mobility and coalescence and also resulted in the flattening of Pd particles on MgO substrates. Electron-beam irradiation further enhanced this effect. Exposure to air for several tens of hours of Pd/MgO led to strong coalescence.

Real time monitoring of filament-assisted chemically vapor deposited diamond by spectroscopic ellipsometry

International Nuclear Information System (INIS)

Yue Cong; An, I.; Vedam, K.; Collins, R.W.; Nguyen, H.V.; Messier, R.

1991-01-01

Spectroscopic ellipsometry over the range 1.5-4.5 eV was applied as a real time probe of the processes occurring in the initial nucleation of thin film diamond by heated-filament assisted chemical vapor deposition. Using both untreated and diamond-polished c-Si substrates, as well as both carburized and uncarburized tungsten filaments, it was possible to separate and characterize competing phenomena, including the increase in surface temperature induced by filament ignition, the formation of carbide layers, contamination of the substrate by tungsten from the filament, annealing of diamond polishing damage, and, finally, diamond nucleation. An accurate measurement of the true temperature of the substrate surface averaged over the top 500 A can be obtained from the energy position of critical points in the c-Si band structure. For diamond deposition, we operated with an initial excess flow of CH 4 to stimulate nucleation. We applied real time feedback and manual control to reduce the CH 4 flow in the first monolayers of deposition. The thickness of diamond and an estimate of its nucleation density can be obtained from real time spectra, and the latter was in good agreement with that obtained from scanning electron microscopy. (orig.)

Application of XML in real-time data warehouse

Science.gov (United States)

Zhao, Yanhong; Wang, Beizhan; Liu, Lizhao; Ye, Su

2009-07-01

At present, XML is one of the most widely-used technologies of data-describing and data-exchanging, and the needs for real-time data make real-time data warehouse a popular area in the research of data warehouse. What effects can we have if we apply XML technology to the research of real-time data warehouse? XML technology solves many technologic problems which are impossible to be addressed in traditional real-time data warehouse, and realize the integration of OLAP (On-line Analytical Processing) and OLTP (Online transaction processing) environment. Then real-time data warehouse can truly be called "real time".

Real-time measurement and control at JET signal processing and physics analysis for diagnostics

International Nuclear Information System (INIS)

Felton, R.; Joffrin, E.; Murari, A.

2005-01-01

To meet the requirements of the scientific programme, the EFDA JET real-time measurement and control project has developed an integrated set of real-time plasma measurements, experiment control and communication facilities. Traditional experiments collected instrument data during the plasma pulse and calculated physics data after the pulse. The challenge for continuous tokamak operation is to calculate the physics data in real-time, keeping up with the evolution of the plasma. In JET, many plasma diagnostics have been augmented with extra data acquisition and signal-processing systems so that they can both capture instrument data for conventional post-pulse analysis and calculate calibrated, validated physics results in real-time. During the pulse, the systems send sampled data sets into a network, which distributes the data to several destinations. The receiving systems may do further analysis, integrating data from several measurements, or may control the plasma scenario by heating or fuelling. The simplest real-time diagnostic systems apply scale factors to the signals, as with the electron cyclotron emission (ECE) diagnostic's 96 tuned radiometer channels, giving the electron temperature profile. In various spectroscopy diagnostics, spectral features are least-squares-fitted to measure spectra from several lines of sight, within 50 ms. Ion temperatures and rotation speed can be calculated from the line widths and shifts. For diagnostics using modulation techniques, the systems implement digital-signal processing phase trackers, lock-in amplifiers and filters, e.g., the far infrared (FIR) interferometer samples 15 channels at 400 kHz for 30 s, i.e., six million samples per second. Diagnostics have specific lines of sight, spatial channels, and various sampling rates. The heating/fuelling systems have relatively coarse spatial localisation. Analysis systems have been developed to integrate the basic physics data into smaller sets of controllable parameters on a

Real-time remote sensing driven river basin modeling using radar altimetry

Directory of Open Access Journals (Sweden)

S. J. Pereira-Cardenal

2011-01-01

Full Text Available Many river basins have a weak in-situ hydrometeorological monitoring infrastructure. However, water resources practitioners depend on reliable hydrological models for management purposes. Remote sensing (RS data have been recognized as an alternative to in-situ hydrometeorological data in remote and poorly monitored areas and are increasingly used to force, calibrate, and update hydrological models.

In this study, we evaluate the potential of informing a river basin model with real-time radar altimetry measurements over reservoirs. We present a lumped, conceptual, river basin water balance modeling approach based entirely on RS and reanalysis data: precipitation was obtained from the Tropical Rainfall Measuring Mission (TRMM Multisatellite Precipitation Analysis (TMPA, temperature from the European Centre for Medium-Range Weather Forecast's (ECMWF Operational Surface Analysis dataset and reference evapotranspiration was derived from temperature data. The Ensemble Kalman Filter was used to assimilate radar altimetry (ERS2 and Envisat measurements of reservoir water levels. The modeling approach was applied to the Syr Darya River Basin, a snowmelt-dominated basin with large topographical variability, several large reservoirs and scarce hydrometeorological data that is located in Central Asia and shared between 4 countries with conflicting water management interests.

The modeling approach was tested over a historical period for which in-situ reservoir water levels were available. Assimilation of radar altimetry data significantly improved the performance of the hydrological model. Without assimilation of radar altimetry data, model performance was limited, probably because of the size and complexity of the model domain, simplifications inherent in model design, and the uncertainty of RS and reanalysis data. Altimetry data assimilation reduced the mean absolute error of the simulated reservoir water levels from 4.7 to 1.9 m, and

Mixed - mode Operating System for Real - time Performance

OpenAIRE

Hasan M. M.; Sultana S.; Foo C.K.

2017-01-01

The purpose of the mixed-mode system research is to handle devices with the accuracy of real-time systems and at the same time, having all the benefits and facilities of a matured Graphic User Interface(GUI)operating system which is typicallynon-real-time. This mixed-mode operating system comprising of a real-time portion and a non-real-time portion was studied and implemented to identify the feasibilities and performances in practical applications (in the context of scheduled the real-time e...

New real-time image processing system for IRFPA

Institute of Scientific and Technical Information of China (English)

WANG Bing-jian; LIU Shang-qian; CHENG Yu-bao

2006-01-01

Influenced by detectors' material,manufacturing technology etc,every detector in infrared focal plane array (IRFPA) will output different voltages even if their input radiation flux is the same.And this is called non-uniformity of IRFPA.At the same time,the high background temperature,low temperature difference between targets and background and the low responsivity of IRFPA result in low contrast of infrared images.So non-uniformity correction and image enhancement are important techniques for IRFPA imaging system.This paper proposes a new real-time infrared image processing system based on Field Programmable Gate Array(FPGA).The system implements non-uniformity correction,image enhancement and video synthesization etc.By using parallel architecture and pipeline technique,the system processing speed is as high as 50Mx12bits per second.It is appropriate greatly to a large IRFPA and a high frame frequency IRFPA imaging system.The system is miniatured in one FPGA.

Mixed-mode Operating System for Real-time Performance

Directory of Open Access Journals (Sweden)

M.M. Hasan

2017-11-01

Full Text Available The purpose of the mixed-mode system research is to handle devices with the accuracy of real-time systems and at the same time, having all the benefits and facilities of a matured Graphic User Interface (GUI operating system which is typically nonreal-time. This mixed-mode operating system comprising of a real-time portion and a non-real-time portion was studied and implemented to identify the feasibilities and performances in practical applications (in the context of scheduled the real-time events. In this research an i8751 microcontroller-based hardware was used to measure the performance of the system in real-time-only as well as non-real-time-only configurations. The real-time portion is an 486DX-40 IBM PC system running under DOS-based realtime kernel and the non-real-time portion is a Pentium III based system running under Windows NT. It was found that mixed-mode systems performed as good as a typical realtime system and in fact, gave many additional benefits such as simplified/modular programming and load tolerance.

Temperature dependence of erythrocyte aggregation in vitro by backscattering nephelometry

Science.gov (United States)

Sirko, Igor V.; Firsov, Nikolai N.; Ryaboshapka, Olga M.; Priezzhev, Alexander V.

1997-05-01

We apply backscattering nephelometry technique to register the alterations of the scattering signal from a whole blood sample due to appearance or disappearance of different types of erythrocyte aggregates in stasis and under controlled shear stress. The measured parameters are: the characteristic times of linear and 3D aggregates formation, and the strength of aggregates of different types. These parameters depend on the sample temperature in the range of 2 divided by 50 degrees C. Temporal parameters of the aggregation process strongly increase at temperature 45 degrees C. For samples of normal blood the aggregates strength parameters do not significantly depend on the sample temperature, whereas for blood samples from patients suffering Sjogren syndrome we observe high increase of the strength of 3D and linear aggregates and decrease of time of linear aggregates formation at low temperature of the sample. This combination of parameters is opposite to that observed in the samples of pathological blood at room temperature. Possible reasons of this behavior of aggregation state of blood and explanation of the observed effects will be discussed.

Time-dependent shock acceleration of energetic electrons including synchrotron losses

International Nuclear Information System (INIS)

Fritz, K.; Webb, G.M.

1990-01-01

The present investigation of the time-dependent particle acceleration problem in strong shocks, including synchrotron radiation losses, solves the transport equation analytically by means of Laplace transforms. The particle distribution thus obtained is then transformed numerically into real space for the cases of continuous and impulsive injections of particles at the shock. While in the continuous case the steady-state spectrum undergoes evolution, impulsive injection is noted to yield such unpredicted features as a pile-up of high-energy particles or a steep power-law with time-dependent spectral index. The time-dependent calculations reveal varying spectral shapes and more complex features for the higher energies which may be useful in the interpretation of outburst spectra. 33 refs

The software and hardware architectural design of the vessel thermal map real-time system in JET

International Nuclear Information System (INIS)

Alves, D.; Neto, A.; Valcarcel, D.F.; Jachmich, S.; Arnoux, G.; Card, P.; Devaux, S.; Felton, R.; Goodyear, A.; Kinna, D.; Lomas, P; McCullen, P.; Stephen, A.; Zastrow, K.D.

2012-01-01

The installation of ITER-relevant materials for the Plasma Facing Components (PFCs) in the Joint European Torus (JET) is expected to have a strong impact on the operation and protection of the experiment. In particular, the use of all-beryllium tiles, which deteriorate at a substantially lower temperature than the formerly installed Carbon Fibre Composite (CFC) tiles, imposes strict thermal restrictions on the PFCs during operation. Prompt and precise responses are therefore required whenever anomalous temperatures are detected. The new Vessel Thermal Map (VTM) real-time application collects the temperature measurements provided by dedicated pyrometers and Infra-Red (IR) cameras, groups them according to spatial location and probable offending heat source and raises alarms that will trigger appropriate protective responses. In the context of JETs global scheme for the protection of the new wall, the system is required to run on a 10 millisecond cycle communicating with other systems through the Real-Time Data Network (RTDN). In order to meet these requirements a Commercial Off- The-Shelf (COTS) solution has been adopted based on standard *86 multi-core technology, Linux and the Multi-threaded Application Real-Time executor (MARTe) software framework. This paper presents an overview of the system with particular technical focus on the configuration of its real-time capability and the benefits of the modular development approach and advanced tools provided by the MARTe framework. (authors)

Temperature dependence of three-body ion-molecule reactions

International Nuclear Information System (INIS)

Boehringer, H.; Arnold, F.

1983-01-01

The temperature dependence of the ion-molecule association reactions (i) N 2 + + N 2 + M → N 4 + + M (M=N 2 , He), (ii) O 2 + + O 2 + M → O 4 + + M (M=O 2 , He) and (iii) He + + 2He → He 2 + + He have been studied over an extended temperature range to temperatures as low as 30K with a recently constructed liquid helium-cooled ion drift tube. Over most of the temperature range the threebody reaction rate coefficients show an inverse temperature dependence proportional to Tsup(-n) with n in the range 0.6 to 2.9. This temperature dependence is quite consistent with current theories of ion molecule association. At low temperatures, however, a deviation from the Tsup(-n) dependence was observed for the association reactions (ii). For reactions (i) different temperature dependences were obtained for N 2 and He third bodies indicating an additional temperature dependence of the collisional stabilisation process. (Authors)

Time-dependent density-functional theory in the projector augmented-wave method

DEFF Research Database (Denmark)

Walter, Michael; Häkkinen, Hannu; Lehtovaara, Lauri

2008-01-01

We present the implementation of the time-dependent density-functional theory both in linear-response and in time-propagation formalisms using the projector augmented-wave method in real-space grids. The two technically very different methods are compared in the linear-response regime where we...

A real-time remote video streaming platform for ultrasound imaging.

Science.gov (United States)

Ahmadi, Mehdi; Gross, Warren J; Kadoury, Samuel

2016-08-01

Ultrasound is a viable imaging technology in remote and resources-limited areas. Ultrasonography is a user-dependent skill which depends on a high degree of training and hands-on experience. However, there is a limited number of skillful sonographers located in remote areas. In this work, we aim to develop a real-time video streaming platform which allows specialist physicians to remotely monitor ultrasound exams. To this end, an ultrasound stream is captured and transmitted through a wireless network into remote computers, smart-phones and tablets. In addition, the system is equipped with a camera to track the position of the ultrasound probe. The main advantage of our work is using an open source platform for video streaming which gives us more control over streaming parameters than the available commercial products. The transmission delays of the system are evaluated for several ultrasound video resolutions and the results show that ultrasound videos close to the high-definition (HD) resolution can be received and displayed on an Android tablet with the delay of 0.5 seconds which is acceptable for accurate real-time diagnosis.

Computing the real-time Green's Functions of large Hamiltonian matrices

OpenAIRE

Iitaka, Toshiaki

1998-01-01

A numerical method is developed for calculating the real time Green's functions of very large sparse Hamiltonian matrices, which exploits the numerical solution of the inhomogeneous time-dependent Schroedinger equation. The method has a clear-cut structure reflecting the most naive definition of the Green's functions, and is very suitable to parallel and vector supercomputers. The effectiveness of the method is illustrated by applying it to simple lattice models. An application of this method...

Testing of real-time-software

International Nuclear Information System (INIS)

Friesland, G.; Ovenhausen, H.

1975-05-01

The situation in the area of testing real-time-software is unsatisfactory. During the first phase of the project PROMOTE (prozessorientiertes Modul- und Gesamttestsystem) an analysis of the momentary situation took place, results of which are summarized in the following study about some user interviews and an analysis of relevant literature. 22 users (industry, software-houses, hardware-manufacturers, and institutes) have been interviewed. Discussions were held about reliability of real-time software with special interest to error avoidance, testing, and debugging. Main aims of the analysis of the literature were elaboration of standard terms, comparison of existing test methods and -systems, and the definition of boundaries to related areas. During the further steps of this project some means and techniques will be worked out to systematically test real-time software. (orig.) [de

Validation and Assessment of Multi-GNSS Real-Time Precise Point Positioning in Simulated Kinematic Mode Using IGS Real-Time Service

Directory of Open Access Journals (Sweden)

Liang Wang

2018-02-01

Full Text Available Precise Point Positioning (PPP is a popular technology for precise applications based on the Global Navigation Satellite System (GNSS. Multi-GNSS combined PPP has become a hot topic in recent years with the development of multiple GNSSs. Meanwhile, with the operation of the real-time service (RTS of the International GNSS Service (IGS agency that provides satellite orbit and clock corrections to broadcast ephemeris, it is possible to obtain the real-time precise products of satellite orbits and clocks and to conduct real-time PPP. In this contribution, the real-time multi-GNSS orbit and clock corrections of the CLK93 product are applied for real-time multi-GNSS PPP processing, and its orbit and clock qualities are investigated, first with a seven-day experiment by comparing them with the final multi-GNSS precise product ‘GBM’ from GFZ. Then, an experiment involving real-time PPP processing for three stations in the Multi-GNSS Experiment (MGEX network with a testing period of two weeks is conducted in order to evaluate the convergence performance of real-time PPP in a simulated kinematic mode. The experimental result shows that real-time PPP can achieve a convergence performance of less than 15 min for an accuracy level of 20 cm. Finally, the real-time data streams from 12 globally distributed IGS/MGEX stations for one month are used to assess and validate the positioning accuracy of real-time multi-GNSS PPP. The results show that the simulated kinematic positioning accuracy achieved by real-time PPP on different stations is about 3.0 to 4.0 cm for the horizontal direction and 5.0 to 7.0 cm for the three-dimensional (3D direction.

Temperature dependence of surface nanobubbles

NARCIS (Netherlands)

Berkelaar, R.P.; Seddon, James Richard Thorley; Zandvliet, Henricus J.W.; Lohse, Detlef

2012-01-01

The temperature dependence of nanobubbles was investigated experimentally using atomic force microscopy. By scanning the same area of the surface at temperatures from 51 °C to 25 °C it was possible to track geometrical changes of individual nanobubbles as the temperature was decreased.

Novel sample preparation for operando TEM of catalysts.

Science.gov (United States)

Miller, Benjamin K; Barker, Trevor M; Crozier, Peter A

2015-09-01

A new TEM sample preparation method is developed to facilitate operando TEM of gas phase catalysis. A porous Pyrex-fiber pellet TEM sample was produced, allowing a comparatively large amount of catalyst to be loaded into a standard Gatan furnace-type tantalum heating holder. The increased amount of catalyst present inside the environmental TEM allows quantitative determination of the gas phase products of a catalytic reaction performed in-situ at elevated temperatures. The product gas concentration was monitored using both electron energy loss spectroscopy (EELS) and residual gas analysis (RGA). Imaging of catalyst particles dispersed over the pellet at atomic resolution is challenging, due to charging of the insulating glass fibers. To overcome this limitation, a metal grid is placed into the holder in addition to the pellet, allowing catalyst particles dispersed over the grid to be imaged, while particles in the pellet, which are assumed to experience identical conditions, contribute to the overall catalytic conversion inside the environmental TEM cell. The gas within the cell is determined to be well-mixed, making this assumption reasonable. Copyright © 2015 Elsevier B.V. All rights reserved.

Temperature-dependent magnetic EXAFS investigation of Gd

CERN Document Server

Wende, H; Poulopoulos, P N; Rogalev, A; Goulon, J; Schlagel, D L; Lograsso, T A; Baberschke, K

2001-01-01

Magnetic EXAFS (MEXAFS) is the helicity-dependent counterpart of the well-established EXAFS technique. By means of MEXAFS it is possible not only to analyze the local magnetic structure but also to learn about magnetic fluctuations. Here we present the MEXAFS of a Gd single crystal at the L sub 3 sub , sub 2 -edges in the temperature range of 10-250 K. For the first time MEXAFS was probed over a large range in reduced temperature of 0.04<=T/T sub C<=0.85 with T sub C =293 K. We show that the vibrational damping described by means of a Debye temperature of theta sub D =160 K must be taken into account for the spin-dependent MEXAFS before analyzing magnetic fluctuations. For a detailed analysis of the MEXAFS and the EXAFS, the experimental data are compared to ab initio calculations. This enables us to separate the individual single- from the multiple-scattering contributions. The MEXAFS data have been recorded at the ID 12A beamline of the European Synchrotron Radiation Facility (ESRF). To ensure that th...

Novel sample preparation for operando TEM of catalysts

International Nuclear Information System (INIS)

Miller, Benjamin K.; Barker, Trevor M.; Crozier, Peter A.

2015-01-01

A new TEM sample preparation method is developed to facilitate operando TEM of gas phase catalysis. A porous Pyrex-fiber pellet TEM sample was produced, allowing a comparatively large amount of catalyst to be loaded into a standard Gatan furnace-type tantalum heating holder. The increased amount of catalyst present inside the environmental TEM allows quantitative determination of the gas phase products of a catalytic reaction performed in-situ at elevated temperatures. The product gas concentration was monitored using both electron energy loss spectroscopy (EELS) and residual gas analysis (RGA). Imaging of catalyst particles dispersed over the pellet at atomic resolution is challenging, due to charging of the insulating glass fibers. To overcome this limitation, a metal grid is placed into the holder in addition to the pellet, allowing catalyst particles dispersed over the grid to be imaged, while particles in the pellet, which are assumed to experience identical conditions, contribute to the overall catalytic conversion inside the environmental TEM cell. The gas within the cell is determined to be well-mixed, making this assumption reasonable. - Highlights: • High in-situ conversion of CO to CO 2 achieved by a novel TEM sample preparation method. • A 3 mm fiber pellet increases the TEM sample surface area by 50×. • Operando atomic resolution is maintained by also including a 3 mm grid in the sample. • Evidence for a well-mixed gas composition inside the ETEM cell is given

The FERMI-Elettra distributed real-time framework

International Nuclear Information System (INIS)

Pivetta, L.; Gaio, G.; Passuello, R.; Scalamera, G.

2012-01-01

FERMI-Elettra is a Free Electron Laser (FEL) based on a 1.5 GeV linac. The pulsed operation of the accelerator and the necessity to characterize and control each electron bunch requires synchronous acquisition of the beam diagnostics together with the ability to drive actuators in real-time at the linac repetition rate. The Adeos/Xenomai real-time extensions have been adopted in order to add real-time capabilities to the Linux based control system computers running the Tango software. A software communication protocol based on Gigabit Ethernet and known as Network Reflective Memory (NRM) has been developed to implement a shared memory across the whole control system, allowing computers to communicate in real-time. The NRM architecture, the real-time performance and the integration in the control system are described. (authors)

Robust adaptive extended Kalman filtering for real time MR-thermometry guided HIFU interventions.

Science.gov (United States)

Roujol, Sébastien; de Senneville, Baudouin Denis; Hey, Silke; Moonen, Chrit; Ries, Mario

2012-03-01

Real time magnetic resonance (MR) thermometry is gaining clinical importance for monitoring and guiding high intensity focused ultrasound (HIFU) ablations of tumorous tissue. The temperature information can be employed to adjust the position and the power of the HIFU system in real time and to determine the therapy endpoint. The requirement to resolve both physiological motion of mobile organs and the rapid temperature variations induced by state-of-the-art high-power HIFU systems require fast MRI-acquisition schemes, which are generally hampered by low signal-to-noise ratios (SNRs). This directly limits the precision of real time MR-thermometry and thus in many cases the feasibility of sophisticated control algorithms. To overcome these limitations, temporal filtering of the temperature has been suggested in the past, which has generally an adverse impact on the accuracy and latency of the filtered data. Here, we propose a novel filter that aims to improve the precision of MR-thermometry while monitoring and adapting its impact on the accuracy. For this, an adaptive extended Kalman filter using a model describing the heat transfer for acoustic heating in biological tissues was employed together with an additional outlier rejection to address the problem of sparse artifacted temperature points. The filter was compared to an efficient matched FIR filter and outperformed the latter in all tested cases. The filter was first evaluated on simulated data and provided in the worst case (with an approximate configuration of the model) a substantial improvement of the accuracy by a factor 3 and 15 during heat up and cool down periods, respectively. The robustness of the filter was then evaluated during HIFU experiments on a phantom and in vivo in porcine kidney. The presence of strong temperature artifacts did not affect the thermal dose measurement using our filter whereas a high measurement variation of 70% was observed with the FIR filter.

Real-time video quality monitoring

Science.gov (United States)

Liu, Tao; Narvekar, Niranjan; Wang, Beibei; Ding, Ran; Zou, Dekun; Cash, Glenn; Bhagavathy, Sitaram; Bloom, Jeffrey

2011-12-01

The ITU-T Recommendation G.1070 is a standardized opinion model for video telephony applications that uses video bitrate, frame rate, and packet-loss rate to measure the video quality. However, this model was original designed as an offline quality planning tool. It cannot be directly used for quality monitoring since the above three input parameters are not readily available within a network or at the decoder. And there is a great room for the performance improvement of this quality metric. In this article, we present a real-time video quality monitoring solution based on this Recommendation. We first propose a scheme to efficiently estimate the three parameters from video bitstreams, so that it can be used as a real-time video quality monitoring tool. Furthermore, an enhanced algorithm based on the G.1070 model that provides more accurate quality prediction is proposed. Finally, to use this metric in real-world applications, we present an example emerging application of real-time quality measurement to the management of transmitted videos, especially those delivered to mobile devices.

Thermal analysis and temperature dependent dielectric responses of Co doped anatase TiO2 nanoparticles

International Nuclear Information System (INIS)

Alamgir; Khan, Wasi; Ahammed, Nashiruddin; Naqvi, A. H.; Ahmad, Shabbir

2015-01-01

Nanoparticles (NPs) of pure and 5 mol % cobalt doped TiO 2 synthesized through acid modified sol-gel method were characterized to understand their thermal, structural, morphological, and temperature dependent dielectric properties. Thermogravimetric analysis (TGA) has been used for thermal studies and indicates the weight loss in two steps due to the removal of residual organics. X-ray diffraction study was employed to confirm the formation of single anatase phase with tetragonal symmetry for both pure and 5 mol % Co doped TiO 2 NPs. The average crystallite size of both samples was calculated from the Scherrer’s formula and was found in the range from 9-11 nm. TEM micrographs of these NPs reflect their shape and distribution. The dielectric constant (ε′), dielectric loss (tanδ) and ac conductivity (σ ac ) were also studied as a function of temperature at different frequencies. Electrical responses of the synthesized NPs have been analyzed carefully in the framework of relevant models. It is also noticed that the dielectric constant (ε′) of the samples found to decrease with increasing frequency but increases with increasing temperature up to a particular value and then sharply decreases. Temperature variation of dielectric constant exhibits step like escalation and shows relaxation behavior. Study of dielectric properties shows dominant dependence on the grain size as well as Co ion incorporation in TiO 2

Indications and techniques of transanal endoscopic microsurgery (TEMS).

Science.gov (United States)

Qi, Yanjie; Stoddard, David; Monson, John R T

2011-08-01

Transanal endoscopic microsurgery (TEMS) has recently reemerged as a valuable technique for the management of rectal neoplasms - both benign and malignant. Since the original description of this technique in the early 1980s, TEMS has emerged as the approach of choice for most benign rectal tumors because of the excellent views provided and superior dissection techniques possible when compared to traditional transanal excision. Many published reports demonstrate that the lowest rates of recurrence are associated with TEMS probably because of full-thickness excision with negative margins. Increasingly, TEMS is being applied to primary rectal cancer when used alone as a full-thickness excision alone or in combination with additional therapies, depending on tumor stage. There is now a significant evidence base to suggest that this approach should be considered as part of a multidisciplinary approach to rectal cancer. This paper describes indications and techniques for this technology.

Luminescence lifetimes in quartz: dependence on annealing temperature prior to beta irradiation

International Nuclear Information System (INIS)

Galloway, R.B.

2002-01-01

It is well known that the thermal history of a quartz sample influences the optically stimulated luminescence sensitivity of the quartz. It is found that the optically stimulated luminescence lifetime, determined from time resolved spectra obtained with pulsed stimulation, also depends on past thermal treatment. For samples at 20 deg. C during stimulation, the lifetime depends on beta dose and on duration of preheating at 220 deg. C prior to stimulation for quartz annealed at 600 deg. C and above, but is independent of these factors for quartz annealed at 500 deg. C and below. For stimulation at higher temperatures, the lifetime becomes shorter if the sample is held at temperatures above 125 deg. C during stimulation, in a manner consistent with thermal quenching. A single exponential decay is all that is required to fit the time resolved spectra for un-annealed quartz regardless of the temperature during stimulation (20-175 deg. C), or to fit the time resolved spectra from all samples held at 20 deg. C during stimulation, regardless of annealing temperature (20-1000 deg. C). An additional shorter lifetime is found for some combinations of annealing temperature and temperature during stimulation. The results are discussed in terms of a model previously used to explain thermal sensitisation. The luminescence lifetime data are best explained by the presence of two principal luminescence centres, their relative importance depending on the annealing temperature, with a third centre involved for limited combinations of annealing temperature and temperature during stimulation