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Sample records for delay lines pdls

  1. Topological Acoustic Delay Line

    Science.gov (United States)

    Zhang, Zhiwang; Tian, Ye; Cheng, Ying; Wei, Qi; Liu, Xiaojun; Christensen, Johan

    2018-03-01

    Topological protected wave engineering in artificially structured media is at the frontier of ongoing metamaterials research that is inspired by quantum mechanics. Acoustic analogues of electronic topological insulators have recently led to a wealth of new opportunities in manipulating sound propagation with strikingly unconventional acoustic edge modes immune to backscattering. Earlier fabrications of topological insulators are characterized by an unreconfigurable geometry and a very narrow frequency response, which severely hinders the exploration and design of useful devices. Here we establish topologically protected sound in reconfigurable phononic crystals that can be switched on and off simply by rotating its three-legged "atoms" without altering the lattice structure. In particular, we engineer robust phase delay defects that take advantage of the ultrabroadband reflection-free sound propagation. Such topological delay lines serve as a paradigm in compact acoustic devices, interconnects, and electroacoustic integrated circuits.

  2. Picosecond resolution programmable delay line

    International Nuclear Information System (INIS)

    Suchenek, Mariusz

    2009-01-01

    The note presents implementation of a programmable delay line for digital signals. The tested circuit has a subnanosecond delay range programmable with a resolution of picoseconds. Implementation of the circuit was based on low-cost components, easily available on the market. (technical design note)

  3. Linear rotary optical delay lines

    Science.gov (United States)

    Guerboukha, Hichem; Qu, Hang; Skorobogatiy, Maksim

    2016-03-01

    We present a semi-analytical solution for the design of a high-speed rotary optical delay line that use a combination of two rotating curvilinear reflectors. We demonstrate that it is possible to design an infinite variety of the optical delay lines featuring linear dependence of the optical delay on the rotation angle. This is achieved via shape optimization of the rotating reflector surfaces. Moreover, a convenient spatial separation of the incoming and outgoing beams is possible. For the sake of example, we present blades that fit into a circle of 10cm diameter. Finally, a prototype of a rotary delay line is fabricated using CNC machining, and its optical properties are characterized.

  4. An FPGA-Integrated Time-to-Digital Converter Based on a Ring Oscillator for Programmable Delay Line Resolution Measurement

    Directory of Open Access Journals (Sweden)

    Chao Chen

    2014-01-01

    Full Text Available We describe the architecture of a time-to-digital converter (TDC, specially intended to measure the delay resolution of a programmable delay line (PDL. The configuration, which consists of a ring oscillator, a frequency divider (FD, and a period measurement circuit (PMC, is implemented in a field programmable gate array (FPGA device. The ring oscillator realized in loop containing a PDL and a look-up table (LUT generates periodic oscillatory pulses. The FD amplifies the oscillatory period from nanosecond range to microsecond range. The time-to-digital conversion is based on counting the number of clock cycles between two consecutive pulses of the FD by the PMC. Experiments have been conducted to verify the performance of the TDC. The achieved relative errors for four PDLs are within 0.50%–1.21% and the TDC has an equivalent resolution of about 0.4 ps.

  5. Assembly delay line pulse generators

    CERN Multimedia

    CERN PhotoLab

    1971-01-01

    Assembly of six of the ten delay line pulse generators that will power the ten kicker magnet modules. One modulator part contains two pulse generators. Capacitors, inductances, and voltage dividers are in the oil tank on the left. Triggered high-pressure spark gap switches are on the platforms on the right. High voltage pulse cables to the kicker magnet emerge under the spark gaps. In the centre background are the assembled master gaps.

  6. Magnetic pulse sharpener and delay-line

    International Nuclear Information System (INIS)

    Li Jin; Dai Guangsen; Xia Liansheng

    2002-01-01

    This paper describes a method to achieve short rise time pulse which has been delayed with a delay-line and magnetic pulse sharpener. A delay-line and two shock-lines are designed to carry pulsed signal with a maximum voltage magnitude up to 80 kV. A pulse of High voltage with arise time of 48 ns at a level of 0.1%-0.9% were achieved, and the attenuation in the line is very small

  7. A Polynomial Estimate of Railway Line Delay

    DEFF Research Database (Denmark)

    Cerreto, Fabrizio; Harrod, Steven; Nielsen, Otto Anker

    2017-01-01

    Railway service may be measured by the aggregate delay over a time horizon or due to an event. Timetables for railway service may dampen aggregate delay by addition of additional process time, either supplement time or buffer time. The evaluation of these variables has previously been performed...... by numerical analysis with simulation. This paper proposes an analytical estimate of aggregate delay with a polynomial form. The function returns the aggregate delay of a railway line resulting from an initial, primary, delay. Analysis of the function demonstrates that there should be a balance between the two...

  8. Delay line MWPC hazard signals inspector

    International Nuclear Information System (INIS)

    Turner, D.B.; Kirsten, F.; Guiragossian, Z.G.T.; Schilling, R.

    1976-01-01

    The Hazard Inspector is a CAMAC module which divides a MWPC delay line into 8 independent signal monitor and control segments. Independent control effectively reduces delay line occupation time and cuts the number of background and non-trigger particles accepted by the 4XQT charge-time-pulse-width digitizer, a device presented in a separate communication. Only segments containing legitimate information are digitized. Non-trigger related events are gated out at the digitizer, and contaminating hits are noted for computer correction

  9. Superconducting delay lines and chirp filters

    International Nuclear Information System (INIS)

    Hoefer, G.J.; Kratz, H.A.

    1993-01-01

    High temperature superconductor (HTSC) thin films are now good enough to realize certain devices, particularly passive analog broadband devices requiring only a single layer of high quality material. This is especially true for long delay lines and related structures, e. g. chirp filters, where low loss and dispersion result in large usable bandwidths. The availability of these devices may hasten the commercialization of the high temperature superconductors, because they take full advantage of their unique properties. (orig.)

  10. Radiofrequency spark chambers and delay line resonators

    International Nuclear Information System (INIS)

    Sayag, Jacques

    1971-01-01

    According to a suggestion of A. Kastler, a spark chamber was excited by an undamped radiofrequency pulse and tracks about 1 mm wide obtained; the result was interpreted by computation of the coefficients of electronic amplification and partial ambipolar diffusion. This work led us to the construction of a new fast triggering undamped wave-train generator of very high tension (patent taken out by the C.E.A. under the no.: EN 7 134 650 the 27.9.1971). Since this apparatus uses a resonant storage line, its design implied a precise knowledge of high impedance delay lines. The experimental radiofrequency spectra of the input impedance of opened or short-circuited lines were plotted completely and analysed by the circuits theory, new measuring methods were established, dispersion relations accurately checked and the equivalence of the formulas, within the third order, with theses of Debye's Dipolar Absorption demonstrated. General properties of Hilbert's transform were also investigated. From the experimental point of view, the electromagnetic energy storage process was extended to the case of a liquid nitrogen-immersed resonant delay line. The good behavior of the cryogenic experiment, where the main difficulty of icing was overcame by the construction of special electrodes, offers great promise for extrapolation to superconductivity. (author) [fr

  11. Multiwire proportional counter (lecture by an electromagnetic delay line)

    International Nuclear Information System (INIS)

    Bruere-Dawson, R.

    1989-01-01

    For track localisation of ionizing particles with multiwire proportional chamber, an electronic chain including amplifying, shaping and memorizing circuits is required for each wire. In order to lower the cost of this type of detector, an electromagnetic delay line is proposed among various possibilities. In this paper, different coupling modes between chamber and delay line are studied with their respective advantages. The realization of one meter long delay line with a unit delay time of 15 ns per cm is also presented [fr

  12. A Polynomial Estimate of Railway Line Delay

    DEFF Research Database (Denmark)

    Cerreto, Fabrizio; Harrod, Steven; Nielsen, Otto Anker

    2017-01-01

    Railway service may be measured by the aggregate delay over a time horizon or due to an event. Timetables for railway service may dampen aggregate delay by addition of additional process time, either supplement time or buffer time. The evaluation of these variables has previously been performed...

  13. Transmission Delay Modeling of Packet Communication over Digital Subscriber Line

    Directory of Open Access Journals (Sweden)

    Jiri Vodrazka

    2013-01-01

    Full Text Available Certain multimedia and voice services, such as VoIP, IPTV, etc., are significantly delay sensitive and their performance is influenced by the overall transmission delay and its variance. One of the most common solutions used in access networks are xDSL lines, especially ADSL2+ or VDSL2. Although these subscriber lines also use packet communication, there are several differences and mechanisms, which influence their resulting delay. Their delay characteristics are also dependent on the individual settings of each xDSL provider, therefore we decided to investigate this area for typical commercially available lines in Czech Republic. Based on the measured values and experiments with real ADSL2+ lines we also developed a potential modeling method, which is presented in this article as well. The parameters for packet jitter based on the generalized Pareto distribution were modeled.

  14. TECHNICAL DESIGN NOTE: Picosecond resolution programmable delay line

    Science.gov (United States)

    Suchenek, Mariusz

    2009-11-01

    The note presents implementation of a programmable delay line for digital signals. The tested circuit has a subnanosecond delay range programmable with a resolution of picoseconds. Implementation of the circuit was based on low-cost components, easily available on the market.

  15. A Delay Line for Compression of Electromagnetic Pulses

    International Nuclear Information System (INIS)

    Pchelnikov, Yuriy N.; Nyce, David S.

    2003-01-01

    A novel method to obtain an electromagnetic signal delay is described. It is shown that the positive magnetic and electric coupling between impedance conductors produces an increase in the time delay. It is also shown that the increase in delay time is obtained without additional attenuation. This allows a reduction in electromagnetic losses, by a factor of several times, for a delay time. An approximate analysis of electromagnetic delay lines based on coupled impedance conductors with 'spiral' and 'meander' patterns allowed obtaining very simple expressions for the wave deceleration factor, wave impedance, and attenuation factor. The results of the analysis are confirmed by the results of measurements. It is shown that a delay line based on counter-wound radial spirals can be successfully used for compression of electromagnetic pulses. Although the offered delay line was designed to operate with a relatively small signal, the analysis of the 'coupling effect', taking place in this delay line, might be useful in devices for compression of high-power microwave pulses

  16. Enhanced Performance & Functionality of Tunable Delay Lines

    Science.gov (United States)

    2012-08-01

    Based Tunable Optical Delays”, Optics Letters, Vol. 33, Issue 13, pp. 1518-1520 (2008). 2. Louis Christen, Irfan Fazal , Omer F. Yilmaz, Xiaoxia Wu...2008. 3. Omer F. Yilmaz, Louis Christen, Xiaoxia Wu, Scott R. Nuccio, Irfan Fazal , and Alan E. Willner, “Time-Slot-Interchange of 40 Gb/s Variable...F. Yilmaz, S. Khaleghi, L. Christen, I. Fazal , and A. E. Willner, “503 ns, Tunable Optical Delay of 40 Gb/s RZ-OOK using Additional λ-Conversion

  17. Delay line clipping in a scintillation camera system

    International Nuclear Information System (INIS)

    Hatch, K.F.

    1979-01-01

    The present invention provides a novel base line restoring circuit and a novel delay line clipping circuit in a scintillation camera system. Single and double delay line clipped signal waveforms are generated for increasing the operational frequency and fidelity of data detection of the camera system by base line distortion such as undershooting, overshooting, and capacitive build-up. The camera system includes a set of photomultiplier tubes and associated amplifiers which generate sequences of pulses. These pulses are pulse-height analyzed for detecting a scintillation having an energy level which falls within a predetermined energy range. Data pulses are combined to provide coordinates and energy of photopeak events. The amplifiers are biassed out of saturation over all ranges of pulse energy level and count rate. Single delay line clipping circuitry is provided for narrowing the pulse width of the decaying electrical data pulses which increase operating speed without the occurrence of data loss. (JTA)

  18. Integrable microwave filter based on a photonic crystal delay line.

    Science.gov (United States)

    Sancho, Juan; Bourderionnet, Jerome; Lloret, Juan; Combrié, Sylvain; Gasulla, Ivana; Xavier, Stephane; Sales, Salvador; Colman, Pierre; Lehoucq, Gaelle; Dolfi, Daniel; Capmany, José; De Rossi, Alfredo

    2012-01-01

    The availability of a tunable delay line with a chip-size footprint is a crucial step towards the full implementation of integrated microwave photonic signal processors. Achieving a large and tunable group delay on a millimetre-sized chip is not trivial. Slow light concepts are an appropriate solution, if propagation losses are kept acceptable. Here we use a low-loss 1.5 mm-long photonic crystal waveguide to demonstrate both notch and band-pass microwave filters that can be tuned over the 0-50-GHz spectral band. The waveguide is capable of generating a controllable delay with limited signal attenuation (total insertion loss below 10 dB when the delay is below 70 ps) and degradation. Owing to the very small footprint of the delay line, a fully integrated device is feasible, also featuring more complex and elaborate filter functions.

  19. A current controlled variable delay superconducting transmission line

    International Nuclear Information System (INIS)

    Anlage, S.M.; Snortland, H.J.; Beasley, M.R.

    1989-01-01

    The authors present a device concept for a current-controlled variable delay for superconducting transmission line. The device makes use of the change in kinetic inductance of a superconducting transmission line under the application of a DC bias current. The relevant materials parameters and several promising superconducting materials have been identified

  20. Delays in switching patients onto second-line antiretroviral treatment ...

    African Journals Online (AJOL)

    Background: South Africa has one of the largest antiretroviral treatment (ART) programmes globally. In addition to increasing access to ART, it is important that the health system also focuses on the appropriate management of patients who fail first-line ART. Delays in switching patients onto second-line ART can adversely ...

  1. Electrically tunable photonic true-time-delay line.

    Science.gov (United States)

    Barmenkov, Yuri O; Cruz, José Luis; Díez, Antonio; Andrés, Miguel V

    2010-08-16

    We present a new application of the acousto-optic superlattice modulation of a fiber Bragg grating based on the dynamic phase and group delay properties of this fiber-optic component. We demonstrate a tunable photonic true-time-delay line based on the group delay change of the light reflected from the grating sidebands. The delay is electrically tuned by adjusting the voltage applied to a piezoelectric transducer that generates the acoustic wave propagating along the grating. In our experiments, a true-time delay of 400 ps is continuously adjusted (300 ps within the 3 dB amplitude range of the first sideband), using a 12 cm long uniform grating.

  2. Survey of transmission line corridors. [Data on delays in transmission line construction

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-05

    The intent of this study is to determine the extent of delays experienced in planning and constructing transmission lines in the continental United States. The reasons for the delays are identified for each line studied and their effect on the total electrical system is sought. Data was collected for 136 different lines either recently built or currently under study. Statistics were developed for each line in several categories and comparisons of lines delayed were made by company, area served and generation capacity. From the study presented here it was found that: right-of-way acquisition procedures including condemnation and easement negotiation practices delay more projects than local, state and federal regulatory requirements combined; load growth reductions particularly in the east have reduced the impact of regulatory delays; the south, southeast and southwestern areas of the country experience fewer delays in constructing transmission lines than the more populated states, and the cost for corridor delays was responded to for only 17 of the 142 projects surveyed. By far the most costly delay is the expense of condemning land for transmission right-of-way.

  3. New β-delayed proton lines from 23Al

    DEFF Research Database (Denmark)

    Kirsebom, Oliver Sølund; Fynbo, H.; Jokinen, A.

    2011-01-01

    We report on a new measurement of the β -delayed proton spectrum of 23 Al. Higher statistics compared to previous measurements allow us to identify new proton lines in the energy range 1--2 MeV. A statistical analysis of the observed β strength shows that the B (GT) values are fully consistent...

  4. Integrated optical delay lines for time-division multiplexers

    NARCIS (Netherlands)

    Stopinski, S.T.; Malinowski, M.; Piramidowicz, R.; Kleijn, E.; Smit, M.K.; Leijtens, X.J.M.

    2013-01-01

    In this paper, we present a study of integrated optical delay lines (DLs) for application in optical time-division multiplexers. The investigated DLs are formed by spirally folded waveguides. The components were designed in a generic approach and fabricated in multi-project wafer runs on an

  5. LHCb: Radiation hard programmable delay line for LHCb Calorimeter Upgrade

    CERN Multimedia

    Mauricio Ferre, J; Vilasís Cardona, X; Picatoste Olloqui, E; Machefert, F; Lefrançois, J; Duarte, O

    2013-01-01

    This poster describes the implementation of a SPI-programmable clock delay chip based on a Delay Locked Loop (DLL) in order to shift the phase of the LHC clock (25 ns) in steps of 1ns, with a 4ps jitter and 18ps of DNL. The delay lines will be integrated into ICECAL, the LHCb calorimeter front-end ASIC in the near future. The stringent noise requirements on the ASIC imply minimizing the noise contribution of digital components. This is accomplished by implementing the DLL in differential mode. To achieve the required radiation tolerance several techniques are applied: double guard rings between PMOS and NMOS transistors as well as glitch suppressors and TMR Registers. This 5.7 mm2 chip has been implemented in CMOS 0.35um technology.

  6. High-explosive-driven delay line pulse generator

    International Nuclear Information System (INIS)

    Shearer, J.W.

    1982-01-01

    The inclusion of a delay line circuit into the design of a high-explosive-driven generator shortens the time constant of the output pulse. After a brief review of generator concepts and previously described pulse-shortening methods, a geometry is presented which incorporates delay line circuit techcniques into a coil generator. The circuit constants are adjusted to match the velocity of the generated electromagnetic wave to the detonation velocity of the high explosive. The proposed generator can be modeled by adding a variable inductance term to the telegrapher's equation. A particular solution of this equation is useful for exploring the operational parameters of the generator. The duration of the electromagnetic pulse equals the radial expansion time of the high-explosive-driven armature until it strikes the coil. Because the impedance of the generator is a constant, the current multiplication factor is limited only by nonlinear effects such as voltage breakdown, diffusion, and compression at high energies

  7. New β-delayed proton lines from 23Al

    International Nuclear Information System (INIS)

    Kirsebom, O.S.; Fynbo, H.O.U.; Riisager, K.; Jokinen, A.; Saastamoinen, A.; Aeystoe, J.; Madurga, M.; Tengblad, O.

    2011-01-01

    We report on a new measurement of the β-delayed proton spectrum of 23 Al. Higher statistics compared to previous measurements allow us to identify new proton lines in the energy range 1-2 MeV. A statistical analysis of the observed β strength shows that the B (GT) values are fully consistent with having a Porter-Thomas distribution. This is indicative of chaotic behaviour and implies that only the average β strength carries physical meaning. (orig.)

  8. Toeless pulse shaping with a single delay-line network

    International Nuclear Information System (INIS)

    Tauhata, L.; Binns, D.C.

    1976-04-01

    New unipolar delay-line clippers producing negligible cancellation remnant have been developed. Near perfect clipping is achieved using a combination of several types of coaxial cable tranformers working as a phase inverter, a new pulse adder, or an impedance transformer. Only passive elements are used in the bridge network. The construction is simple and the performance is extremely stable and wide in dynamic range and frequency band width. Completely symmetrical bipolar pulses are also easily obtained using this technique

  9. Delay estimation on a railway-line with smart use of micro-simulation

    DEFF Research Database (Denmark)

    Cerreto, Fabrizio; Harrod, Steven; Nielsen, Otto Anker

    2017-01-01

    This paper formulates a delay propagation model that estimates total railway line delay as a polynomial function of a single primary delay. The estimate is derived from a finite series of delays over a horizon that spans two dimensions: the length of the railway line and the number of trains in t...

  10. A scheme to expand the delay-bandwidth product in the resonator-based delay lines by optical OFDM technique

    DEFF Research Database (Denmark)

    Zhu, Jiangbo; Tao, Li; Zhang, Ziran

    2013-01-01

    We propose a novel scheme to expand the inherent limit in the product of the optical delay and the transmission bandwidth in resonator-based delay lines, with the optical orthogonal frequency division multiplexing (OOFDM) technique. The optical group delay properties of a single ring resonator we...

  11. Optical True Time Delay for Phased Array Antennas Composed of 2×2 Optical MEMS Switches and Fiber Delay Lines

    Institute of Scientific and Technical Information of China (English)

    Back-Song; Lee; Jong-Dug; Shin; Boo-Gyoun; Kim

    2003-01-01

    We proposed an optical true time delay (TTD) for phased array antennas (PAAs) composed of 2×2 optical MEMS switches, single-mode fiber delay lines, and a fixed wavelength laser diode. A 3-bit TTD for 10 GHz PAAs was implemented with a time delay error less than ± 0.2 ps.

  12. ESO and Fokker Space Sign Contract about VLTI Delay Line

    Science.gov (United States)

    1998-03-01

    The European Southern Observatory is building the world's largest optical telescope, the Very Large Telescope (VLT) , at the ESO Paranal Observatory in Chile. The VLT consists of four 8.2-m unit telescopes and several smaller, moveable Auxiliary Telescopes. When coupled as the giant VLT Interferometer (VLTI) , they will together provide the sharpest images ever obtained by any optical telescope. It will in principle be able to see an astronaut on the surface of the Moon, 400,000 km away. The VLTI Delay Lines Fokker Space (Leiden, The Netherlands) has been awarded a contract for the delivery of the Delay Line of the VLTI. This is a mechanical-optical system that will compensate the optical path differences of the light beams from the individual telescopes. Such a system is necessary to ensure that the light from all telescopes arrive in the same phase at the focal point of the interferometer. Otherwise, the very sharp interferometric images cannot be obtained. ESO PR Photo 08/98 [JPEG, 102k] Schematic representation of the VLTI Delay Line, showing the retro-reflector on its moving base. For more details, please consult the technical explanation below. This highly accurate system will be developed in close co-operation with the Dutch institute TNO-TPD (Netherlands Organization for Applied Scientific Research - Institute of Applied Physics) . The most innovative feature of the Delay Line is the new control strategy, a two-stage control system, based on linear motor technology, combined with high accuracy piezo-electric control elements. This enables the system to position the so-called cat's eye reflector system with an accuracy of only a few nanometers (millionth of a millimetre (nm)) over a stroke length of 60 metres. Within radio astronomy, interferometric techniques have been applied by Dutch astronomers since many years. They will now be able to contribute with their extensive knowledge of such systems to the next generation of astronomical interferometric

  13. Estimating Angle of Arrival (AOA for Wideband Signal by Sensor Delay Line (SDL and Tapped Delay Line (TDL Processors

    Directory of Open Access Journals (Sweden)

    Bassim Sayed Mohammed

    2018-04-01

    Full Text Available Angle of arrival (AOA estimation for wideband signal becomes more necessary for modern communication systems like Global System for Mobile (GSM, satellite, military applications and spread spectrum (frequency hopping and direct sequence. Most of the researchers are focusing on how to cancel the effects of signal bandwidth on AOA estimation performance by using a transversal filter (tap delay line (TDL. Most of the researchers were using two elements array antenna to study these effects. In this research, a general case of proposed (M array elements is used. A transversal filter (TDL in phase adaptive array antenna system is used to calculate the optimum number of taps required to compensate these effect. The proposed system uses a phase adaptive array antenna in conjunction with LMS algorithm to work an angle of arrival (AOA estimator for wideband signals rather than interference canceller. An alternative solution to compensate for the effect of signal bandwidth is proposed by using sensor delay line (SDL instead of fixed delay unit since it has variable time sampling in the time domain and not fixed time delay, depending on the angle of arrival of received signals. The proposed system has the ability to estimate two parameters for received signals simultaneously (the output Signal to Noise Ratio (SNR and AOA, unlike others systems which estimate AOA only. The comparison of the simulation results with Multiple Signal Classification (MUSIC technique showed that the proposed system gives good results for estimating AOA and the output SNR for wideband signals. (SDL processor shows better performance result than (TDL processor. MUSIC technique with both (SDL and (TDL processors shows unacceptable results for estimating (AOA for the wideband signal.

  14. Real-time pulse deinterleaving using digital delay line techniques

    Science.gov (United States)

    Lentz, L. F.; Palermo, T. J.

    This paper describes an implementation of a tracking pulse sorter based on predictive gating techniques. Real-time pulse sorters or pulse train gating devices have been utilized by the ELINT signal analyst for many years. The more elementary of these devices employed a retriggerable delay interval and an acceptance gate, which were used in predictive fashion to track pulse trains whose PRIs fall within the limits of the programmed delay interval. This design utilizes the pulse hit/miss history of individual track files in a variation of a sequential observer detection algorithm. Use of a digital delay line with pulse history allows multiple pulse trains to be tracked simultaneously and independently without interference. The design also provides flexibility in lock-on and track criteria to allow maintenance of acquisition probability and false alarm rate in dense signal environments and with low SNRs. The hardware provides time interval resolution to 12.5 nsec and covers a PRI range of 50 microsec to 50 msec.

  15. Delay-Line Three-Dimensional Position Sensitive Radiation Detection

    Science.gov (United States)

    Jeong, Manhee

    High-resistivity silicon(Si) in large volumes and with good charge carrier transport properties has been produced and achieved success as a radiation detector material over the past few years due to its relatively low cost as well as the availability of well-established processing technologies. One application of that technology is in the fabrication of various position-sensing topologies from which the incident radiation's direction can be determined. We have succeeded in developing the modeling tools for investigating different position-sensing schemes and used those tools to examine both amplitude-based and time-based methods, an assessment that indicates that fine position-sensing can be achieved with simpler readout designs than are conventionally deployed. This realization can make ubiquitous and inexpensive deployment of special nuclear materials (SNM) detecting technology becomes more feasible because if one can deploy position-sensitive semiconductor detectors with only one or two contacts per side. For this purpose, we have described the delay-line radiation detector and its optimized fabrication. The semiconductor physics were simulated, the results from which guided the fabrication of the guard ring structure and the detector electrode, both of which included metal-field-plates. The measured improvement in the leakage current was confirmed with the fabricated devices, and the structures successfully suppressed soft-breakdown. We also demonstrated that fabricating an asymmetric strip-line structure successfully minimizing the pulse shaping and increases the distance through which one can propagate the information of the deposited charge distribution. With fabricated delay-line detectors we can acquire alpha spectra (Am-241) and gamma spectra (Ba-133, Co-57 and Cd-109). The delay-line detectors can therefore be used to extract the charge information from both ion and gamma-ray interactions. Furthermore, standard charge-sensitive circuits yield high SNR

  16. A review on high-resolution CMOS delay lines: towards sub-picosecond jitter performance.

    Science.gov (United States)

    Abdulrazzaq, Bilal I; Abdul Halin, Izhal; Kawahito, Shoji; Sidek, Roslina M; Shafie, Suhaidi; Yunus, Nurul Amziah Md

    2016-01-01

    A review on CMOS delay lines with a focus on the most frequently used techniques for high-resolution delay step is presented. The primary types, specifications, delay circuits, and operating principles are presented. The delay circuits reported in this paper are used for delaying digital inputs and clock signals. The most common analog and digitally-controlled delay elements topologies are presented, focusing on the main delay-tuning strategies. IC variables, namely, process, supply voltage, temperature, and noise sources that affect delay resolution through timing jitter are discussed. The design specifications of these delay elements are also discussed and compared for the common delay line circuits. As a result, the main findings of this paper are highlighting and discussing the followings: the most efficient high-resolution delay line techniques, the trade-off challenge found between CMOS delay lines designed using either analog or digitally-controlled delay elements, the trade-off challenge between delay resolution and delay range and the proposed solutions for this challenge, and how CMOS technology scaling can affect the performance of CMOS delay lines. Moreover, the current trends and efforts used in order to generate output delayed signal with low jitter in the sub-picosecond range are presented.

  17. New approach to design and performance assessment of delay lines for radioactive rare gases

    International Nuclear Information System (INIS)

    Wilhelmova, L.; Dvorak, Z.; Cejnar, F.

    1981-01-01

    The evaluation and analysis are discussed of the dynamic adsorption of rare gases in the delay lines of nuclear power plants. The method of statistical momenta was used for deriving relations for the calculation of penetration curves of radioactive isotopes of rare gases through a delay line. Relations were also derived for the calculation of the capacity of delay line adsorption beds for both continuous and discontinuous operation. The procedures for the design and the derivation of the function of delay lines take into account the actual conditions of delay line operation in nuclear power plants. (author)

  18. Realization of compact tractor beams using acoustic delay-lines

    Science.gov (United States)

    Marzo, A.; Ghobrial, A.; Cox, L.; Caleap, M.; Croxford, A.; Drinkwater, B. W.

    2017-01-01

    A method for generating stable ultrasonic levitation of physical matter in air using single beams (also known as tractor beams) is demonstrated. The method encodes the required phase modulation in passive unit cells into which the ultrasonic sources are mounted. These unit cells use waveguides such as straight and coiled tubes to act as delay-lines. It is shown that a static tractor beam can be generated using a single electrical driving signal, and a tractor beam with one-dimensional movement along the propagation direction can be created with two signals. Acoustic tractor beams capable of holding millimeter-sized polymer particles of density 1.25 g/cm3 and fruit-flies (Drosophila) are demonstrated. Based on these design concepts, we show that portable tractor beams can be constructed with simple components that are readily available and easily assembled, enabling applications in industrial contactless manipulation and biophysics.

  19. Ultra-precision turning of complex spiral optical delay line

    Science.gov (United States)

    Zhang, Xiaodong; Li, Po; Fang, Fengzhou; Wang, Qichang

    2011-11-01

    Optical delay line (ODL) implements the vertical or depth scanning of optical coherence tomography, which is the most important factor affecting the scanning resolution and speed. The spinning spiral mirror is found as an excellent optical delay device because of the high-speed and high-repetition-rate. However, it is one difficult task to machine the mirror due to the special shape and precision requirement. In this paper, the spiral mirror with titled parabolic generatrix is proposed, and the ultra-precision turning method is studied for its machining using the spiral mathematic model. Another type of ODL with the segmental shape is also introduced and machined to make rotation balance for the mass equalization when scanning. The efficiency improvement is considered in details, including the rough cutting with the 5- axis milling machine, the machining coordinates unification, and the selection of layer direction in turning. The onmachine measuring method based on stylus gauge is designed to analyze the shape deviation. The air bearing is used as the measuring staff and the laser interferometer sensor as the position sensor, whose repeatability accuracy is proved up to 10nm and the stable feature keeps well. With this method developed, the complex mirror with nanometric finish of 10.7nm in Ra and the form error within 1um are achieved.

  20. Magnonic Crystal as a Delay Line for Low-Noise Auto-Oscillator

    Science.gov (United States)

    2015-05-12

    Magnonic crystal as a delay line for low-noise auto-oscillator Elena Bankowski and Thomas Meitzler U.S. Army TARDEC, Warren, Michigan 48397, USA...authors propose to use the magnonic crystal patterned on the YIG magnetic film as an efficient delay line in the feedback loop of tunable auto-oscillator...increasing the thickness of such delay line as compare to the YIG film with no pattern. In turn, use of this magnonic crystal opens a way to improve

  1. A new delay line loops shrinking time-to-digital converter in low-cost FPGA

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jie, E-mail: zhangjie071063@163.com [State Key Laboratory of Geodesy and Earth’s Dynamics, Institute of Geodesy and Geophysics, CAS, Wuhan, China, 430077 (China); University of Chinese Academy of Sciences, Beijing, China, 100049 (China); Zhou, Dongming [State Key Laboratory of Geodesy and Earth’s Dynamics, Institute of Geodesy and Geophysics, CAS, Wuhan, China, 430077 (China)

    2015-01-21

    The article provides the design and test results of a new time-to-digital converter (TDC) based on delay line loops shrinking method and implemented in a low-cost field programmable gate array (FPGA) device. A technique that achieves high resolution with low cost and flexibility is presented. The technique is based on two delay line loops which are used to directly shrink the measured time interval in the designed TDC, and the resolution is dependent on the difference between the entire delay times of the two delay line loops. In order to realize high resolution and eliminate temperature influence, the two delay line loops consist of the same delay cells with the same number. A delay-locked loop (DLL) is used to stabilize the resolution against process variations and ambient conditions. Meanwhile, one method is used to accurately evaluate the resolution of the implemented TDC. The converter has been implemented in a general-propose FPGA device (Actel SmartFusion A2F200M3). A single shot resolution of the implemented converter is 63.3 ps and the measurement standard deviation is about 61.7 ps within the measurement range of 5 ns. - Highlights: • We provide a new FPGA-integrated time-to-digital converter based on delay line loops method which used two delay line loops to directly shrink time intervals with only rising edges. • The two delay line loops consist of the same delay cells with the same number and symmetrical structure. • The resolution is dependent on the difference between the entire delays of the two delay line loops. • We use delay-locked loop to stabilize the resolution against temperature and supply voltage.

  2. A new delay line loops shrinking time-to-digital converter in low-cost FPGA

    International Nuclear Information System (INIS)

    Zhang, Jie; Zhou, Dongming

    2015-01-01

    The article provides the design and test results of a new time-to-digital converter (TDC) based on delay line loops shrinking method and implemented in a low-cost field programmable gate array (FPGA) device. A technique that achieves high resolution with low cost and flexibility is presented. The technique is based on two delay line loops which are used to directly shrink the measured time interval in the designed TDC, and the resolution is dependent on the difference between the entire delay times of the two delay line loops. In order to realize high resolution and eliminate temperature influence, the two delay line loops consist of the same delay cells with the same number. A delay-locked loop (DLL) is used to stabilize the resolution against process variations and ambient conditions. Meanwhile, one method is used to accurately evaluate the resolution of the implemented TDC. The converter has been implemented in a general-propose FPGA device (Actel SmartFusion A2F200M3). A single shot resolution of the implemented converter is 63.3 ps and the measurement standard deviation is about 61.7 ps within the measurement range of 5 ns. - Highlights: • We provide a new FPGA-integrated time-to-digital converter based on delay line loops method which used two delay line loops to directly shrink time intervals with only rising edges. • The two delay line loops consist of the same delay cells with the same number and symmetrical structure. • The resolution is dependent on the difference between the entire delays of the two delay line loops. • We use delay-locked loop to stabilize the resolution against temperature and supply voltage

  3. Development of a non-delay-line constant-fraction discriminator

    International Nuclear Information System (INIS)

    Yang Tao; Zhao Bo; Zhang Chi

    2002-01-01

    A Non-Delay-Line Constant-Fraction Discriminator (CFD) timing circuit is introduced. The delay line in the CFD is replaced with a low pass filter in this simplified circuit. The timing resolution of the CFD is better than 150 ps

  4. Mixed Modeling of a SAW Delay Line Using VHDL-AMS

    Science.gov (United States)

    Wilson, William C.; Atkinson, Gary M.

    2006-01-01

    To aid in the development of SAW sensors for aerospace applications we have created a model of a SAW Delay line using VHDL. The model implements the Impulse Response method to calculate the frequency response, impedance, and insertion loss. The model includes optimization for the number of finger pairs in the IDTs and for the aperture height. This paper presents the model and the results from the model for a SAW delay line design.

  5. A digital TDC with a reduced number of delay line cells

    International Nuclear Information System (INIS)

    Boujrad, A.; Bloyet, D.; Tripon, M.

    2002-01-01

    In nuclear physics experiments, a decision maker named as 'trigger' gives a bit pattern which allows the fired detectors identification. As the data acquisition dead time is greater than the time between physical events, timing information is essential. We add to the trigger function a Time to Digital Converter (TDC) in order to make a separation between events. The paper describes the architecture chosen for the TDC and illustrates the contribution of each element to the TDC performance. An eight-bit counter is used for the dynamic range of the TDC (in microsecond) associated to a delay line improving the resolution (in nanosecond). The study shows that exploiting the two system clock states (high and low) allows to reduce the number of delay line cells. The Differential Nonlinearity Measurements are given for different resolutions (1, 2 and 5 ns) and illustrate the clock period, the clock duty cycle and the delay line contributions to the TDC performances

  6. A monolithic constant-fraction discriminator using distributed R-C delay-line shaping

    International Nuclear Information System (INIS)

    Simpson, M.L.; Young, G.R.; Xu, M.

    1995-01-01

    A monolithic, CMOS, constant-fraction discriminator (CFD) was fabricated in the Orbit Semiconductor, 1.2 μ N-well process. This circuit uses an on-chip, distributed, R-C delay-line to realize the constant-fraction shaping. The delay-line is constructed from a narrow, 500-μ serpentine layer of polysilicon above a wide, grounded, second layer of polysilicon. This R-C delay-line generates about 1.1 ns of delay for 5 ns risetime signals with a slope degradation of only ≅ 15% and an amplitude reduction of about 6.1%. The CFD also features an automatic walk adjustment. The entire circuit, including the delay line, has a 200 μ pitch and is 950 μ long. The walk for a 5 ns risetime signal was measured as ± 100 ps over the 100:1 dynamic range from -15 mV to -1.5 mV. to -1.5 V. The CFD consumes 15 mW

  7. Several key issues on implementing delay line based TDCs using FPGAs

    International Nuclear Information System (INIS)

    Wu, Jinyuan

    2009-01-01

    Several topics in FPGA delay line based TDCs are discussed in this document. First, FPGA specific issues such as considerations on the delay line choice in different FPGA families, Wave Union Launchers, 'bubble proof' encoding logic, etc. are examined. Next, common problems for both FPGA TDCs and ASIC TDCs such as schemes of coarse time counter implementation, bin-by-bin calibration and noise issues due to single ended signals are discussed. Several resource/power saving design approaches for various processing stages are described in the document.

  8. Multimoded rf delay line distribution system for the Next Linear Collider

    Directory of Open Access Journals (Sweden)

    S. G. Tantawi

    2002-03-01

    Full Text Available The delay line distribution system is an alternative to conventional pulse compression, which enhances the peak power of rf sources while matching the long pulse of those sources to the shorter filling time of accelerator structures. We present an implementation of this scheme that combines pairs of parallel delay lines of the system into single lines. The power of several sources is combined into a single waveguide delay line using a multimode launcher. The output mode of the launcher is determined by the phase coding of the input signals. The combined power is extracted from the delay line using mode-selective extractors, each of which extracts a single mode. Hence, the phase coding of the sources controls the output port of the combined power. The power is then fed to the local accelerator structures. We present a detailed design of such a system, including several implementation methods for the launchers, extractors, and ancillary high power rf components. The system is designed so that it can handle the 600 MW peak power required by the Next Linear Collider design while maintaining high efficiency.

  9. Micromachined silicon parallel acoustic delay lines as time-delayed ultrasound detector array for real-time photoacoustic tomography

    Science.gov (United States)

    Cho, Y.; Chang, C.-C.; Wang, L. V.; Zou, J.

    2016-02-01

    This paper reports the development of a new 16-channel parallel acoustic delay line (PADL) array for real-time photoacoustic tomography (PAT). The PADLs were directly fabricated from single-crystalline silicon substrates using deep reactive ion etching. Compared with other acoustic delay lines (e.g., optical fibers), the micromachined silicon PADLs offer higher acoustic transmission efficiency, smaller form factor, easier assembly, and mass production capability. To demonstrate its real-time photoacoustic imaging capability, the silicon PADL array was interfaced with one single-element ultrasonic transducer followed by one channel of data acquisition electronics to receive 16 channels of photoacoustic signals simultaneously. A PAT image of an optically-absorbing target embedded in an optically-scattering phantom was reconstructed, which matched well with the actual size of the imaged target. Because the silicon PADL array allows a signal-to-channel reduction ratio of 16:1, it could significantly simplify the design and construction of ultrasonic receivers for real-time PAT.

  10. Micromachined silicon parallel acoustic delay lines as time-delayed ultrasound detector array for real-time photoacoustic tomography

    International Nuclear Information System (INIS)

    Cho, Y; Chang, C-C; Zou, J; Wang, L V

    2016-01-01

    This paper reports the development of a new 16-channel parallel acoustic delay line (PADL) array for real-time photoacoustic tomography (PAT). The PADLs were directly fabricated from single-crystalline silicon substrates using deep reactive ion etching. Compared with other acoustic delay lines (e.g., optical fibers), the micromachined silicon PADLs offer higher acoustic transmission efficiency, smaller form factor, easier assembly, and mass production capability. To demonstrate its real-time photoacoustic imaging capability, the silicon PADL array was interfaced with one single-element ultrasonic transducer followed by one channel of data acquisition electronics to receive 16 channels of photoacoustic signals simultaneously. A PAT image of an optically-absorbing target embedded in an optically-scattering phantom was reconstructed, which matched well with the actual size of the imaged target. Because the silicon PADL array allows a signal-to-channel reduction ratio of 16:1, it could significantly simplify the design and construction of ultrasonic receivers for real-time PAT. (paper)

  11. Micromachined silicon acoustic delay line with improved structural stability and acoustic directivity for real-time photoacoustic tomography

    Science.gov (United States)

    Cho, Young; Kumar, Akhil; Xu, Song; Zou, Jun

    2017-03-01

    Recent studies have shown that micromachined silicon acoustic delay lines can provide a promising solution to achieve real-time photoacoustic tomography without the need for complex transducer arrays and data acquisition electronics. However, as its length increases to provide longer delay time, the delay line becomes more vulnerable to structural instability due to reduced mechanical stiffness. In addition, the small cross-section area of the delay line results in a large acoustic acceptance angle and therefore poor directivity. To address these two issues, this paper reports the design, fabrication, and testing of a new silicon acoustic delay line enhanced with 3D printed polymer micro linker structures. First, mechanical deformation of the silicon acoustic delay line (with and without linker structures) under gravity was simulated by using finite element method. Second, the acoustic crosstalk and acoustic attenuation caused by the polymer micro linker structures were evaluated with both numerical simulation and ultrasound transmission testing. The result shows that the use of the polymer micro linker structures significantly improves the structural stability of the silicon acoustic delay lines without creating additional acoustic attenuation and crosstalk. In addition, a new tapered design for the input terminal of the delay line was also investigate to improve its acoustic directivity by reducing the acoustic acceptance angle. These two improvements are expected to provide an effective solution to eliminate current limitations on the achievable acoustic delay time and out-of-plane imaging resolution of micromachined silicon acoustic delay line arrays.

  12. Subwavelength grating enabled on-chip ultra-compact optical true time delay line.

    Science.gov (United States)

    Wang, Junjia; Ashrafi, Reza; Adams, Rhys; Glesk, Ivan; Gasulla, Ivana; Capmany, José; Chen, Lawrence R

    2016-07-26

    An optical true time delay line (OTTDL) is a basic photonic building block that enables many microwave photonic and optical processing operations. The conventional design for an integrated OTTDL that is based on spatial diversity uses a length-variable waveguide array to create the optical time delays, which can introduce complexities in the integrated circuit design. Here we report the first ever demonstration of an integrated index-variable OTTDL that exploits spatial diversity in an equal length waveguide array. The approach uses subwavelength grating waveguides in silicon-on-insulator (SOI), which enables the realization of OTTDLs having a simple geometry and that occupy a compact chip area. Moreover, compared to conventional wavelength-variable delay lines with a few THz operation bandwidth, our index-variable OTTDL has an extremely broad operation bandwidth practically exceeding several tens of THz, which supports operation for various input optical signals with broad ranges of central wavelength and bandwidth.

  13. Control of operating parameters of laser ceilometers with the application of fiber optic delay line imitation

    Science.gov (United States)

    Kim, A. A.; Klochkov, D. V.; Konyaev, M. A.; Mihaylenko, A. S.

    2017-11-01

    The article considers the problem of control and verification of the laser ceilometers basic performance parameters and describes an alternative method based on the use of multi-length fiber optic delay line, simulating atmospheric track. The results of the described experiment demonstrate the great potential of this method for inspection and verification procedures of laser ceilometers.

  14. A new time-digital convert circuit based on digital delay line

    International Nuclear Information System (INIS)

    Liu Haifeng; Guo Ying; Zhang Zhi

    2004-01-01

    An introduction of a new method of time-digital convert circuit based on digital delay line is given. High precision and good reliability can be realized when it is combined with traditional counting convert method in the measurement of large scale pulse width and low frequency self-excitation oscillator. (authors)

  15. Constructing Hopf bifurcation lines for the stability of nonlinear systems with two time delays

    Science.gov (United States)

    Nguimdo, Romain Modeste

    2018-03-01

    Although the plethora real-life systems modeled by nonlinear systems with two independent time delays, the algebraic expressions for determining the stability of their fixed points remain the Achilles' heel. Typically, the approach for studying the stability of delay systems consists in finding the bifurcation lines separating the stable and unstable parameter regions. This work deals with the parametric construction of algebraic expressions and their use for the determination of the stability boundaries of fixed points in nonlinear systems with two independent time delays. In particular, we concentrate on the cases for which the stability of the fixed points can be ascertained from a characteristic equation corresponding to that of scalar two-delay differential equations, one-component dual-delay feedback, or nonscalar differential equations with two delays for which the characteristic equation for the stability analysis can be reduced to that of a scalar case. Then, we apply our obtained algebraic expressions to identify either the parameter regions of stable microwaves generated by dual-delay optoelectronic oscillators or the regions of amplitude death in identical coupled oscillators.

  16. A low dead time vernier delay line TDC implemented in an Actel flash-based FPGA

    International Nuclear Information System (INIS)

    Qin Xi; Feng Changqing; Zhang Deliang; Zhao Lei; Liu Shubin; An Qi

    2013-01-01

    In this paper, a high precision vernier delay line (VDL) TDC (Time-to-Digital Converter) in an Actel flash-based Field-Programmable-Gate-Arrays A3PE1500 is implemented, achieving a resolution of 16.4-ps root mean square value or 42-ps averaged bin size. The TDC has a dead time of about 200 ns while the dynamic range is 655.36 Vs. The double delay lines method is employed to cut the dead time in half to improve its performance. As the bin size of the TDC is dependent on temperature, a compensation algorithm is adopted as temperature drift correction, and the TDC shows satisfying performance in a temperature range from -5℃ to +55℃. (authors)

  17. Synchronization and bidirectional communication without delay line using strong mutually coupled semiconductor lasers

    Science.gov (United States)

    Li, Guang-Hui; Wang, An-Bang; Feng, Ye; Wang, Yang

    2010-07-01

    This paper numerically demonstrates synchronization and bidirectional communication without delay line by using two semiconductor lasers with strong mutual injection in a face-to-face configuration. These results show that both of the two lasers' outputs synchronize with their input chaotic carriers. In addition, simulations demonstrate that this kind of synchronization can be used to realize bidirectional communications without delay line. Further studies indicate that within a small deviation in message amplitudes of two sides (±6%), the message can be extracted with signal-noise-ratio more than 10 dB; and the signal-noise-ratio is extremely sensitive to the message rates mismatch of two sides, which may be used as a key of bidirectional communication.

  18. Synchronization and bidirectional communication without delay line using strong mutually coupled semiconductor lasers

    International Nuclear Information System (INIS)

    Guang-Hui, Li; An-Bang, Wang; Ye, Feng; Yang, Wang

    2010-01-01

    This paper numerically demonstrates synchronization and bidirectional communication without delay line by using two semiconductor lasers with strong mutual injection in a face-to-face configuration. These results show that both of the two lasers' outputs synchronize with their input chaotic carriers. In addition, simulations demonstrate that this kind of synchronization can be used to realize bidirectional communications without delay line. Further studies indicate that within a small deviation in message amplitudes of two sides (±6%), the message can be extracted with signal-noise-ratio more than 10 dB; and the signal-noise-ratio is extremely sensitive to the message rates mismatch of two sides, which may be used as a key of bidirectional communication. (general)

  19. Characteristics of a delay-line readout in a cylindrical drift chamber system

    International Nuclear Information System (INIS)

    Barber, R.; Ahmed, M.W.; Dzemidzic, M.; Empl, A.; Hungerford, E.V.; Lan, K.J.; Wilson, J.; Cooper, M.D.; Gagliardi, C.A.; Haim, D.; Kim, G.J.; Koetke, D.D.; Tribble, R.E.; Van Ausdeln, L.A.

    2002-01-01

    This paper reports on the design, construction, and operational characteristics of a delay-line readout implemented on the cathode foils of a cylindrical drift chamber system. The readout was used to determine the position of an event along the length of the 1.74 m drift wires in the MEGA detectors used at the Los Alamos Meson Physics Facility. The performance of the system is interpreted by comparison to a PSPICE simulation, and to simple analytical models

  20. Delay-line cables for the fast bumpers in the PS.

    CERN Multimedia

    CERN PhotoLab

    1976-01-01

    For 'continuous transfer' to the SPS, the beam accelerated in the PS is shaved off over several turns, so as to form a continuous sequence of bunches several times the length of the PS circumference. Fast bumpers, powered in a 'staircase' way, displace the PS beam stepwise towards the ejection septum. Each step lasts 2.1 microsec and the cable drums in this picture contain some of the bumper delay-lines of altogether 10 km.

  1. A two-dimensional detector with delay line readout for slow neutron fields measurements

    International Nuclear Information System (INIS)

    Cheremukhina, G.A.; Chernenko, S.P.; Ivanov, A.B.

    1992-01-01

    This article presents the description of a two-dimensional detector of slow neutrons together with its readout and data acquisition electronics based on a PC/AT> The detector with a sensitive area of 260x140 mm 2 is based on a high pressure multiwire proportional chamber with delay line readout and gas filling of 3.0 atm. 3 He + propane. 25 refs.; 10 figs.; 2 tabs

  2. Active high-power RF pulse compression using optically switched resonant delay lines

    International Nuclear Information System (INIS)

    Tantawi, S.G.; Ruth, R.D.; Vlieks, A.E.

    1996-11-01

    The authors present the design and a proof of principle experimental results of an optically controlled high power rf pulse compression system. The design should, in principle, handle few hundreds of Megawatts of power at X-band. The system is based on the switched resonant delay line theory. It employs resonant delay lines as a means of storing rf energy. The coupling to the lines is optimized for maximum energy storage during the charging phase. To discharge the lines, a high power microwave switch increases the coupling to the lines just before the start of the output pulse. The high power microwave switch, required for this system, is realized using optical excitation of an electron-hole plasma layer on the surface of a pure silicon wafer. The switch is designed to operate in the TE 01 mode in a circular waveguide to avoid the edge effects present at the interface between the silicon wafer and the supporting waveguide; thus, enhancing its power handling capability

  3. Measuring a Fiber-Optic Delay Line Using a Mode-Locked Laser

    Science.gov (United States)

    Tu, Meirong; McKee, Michael R.; Pak, Kyung S.; Yu, Nan

    2010-01-01

    The figure schematically depicts a laboratory setup for determining the optical length of a fiber-optic delay line at a precision greater than that obtainable by use of optical time-domain reflectometry or of mechanical measurement of length during the delay-line-winding process. In this setup, the delay line becomes part of the resonant optical cavity that governs the frequency of oscillation of a mode-locked laser. The length can then be determined from frequency-domain measurements, as described below. The laboratory setup is basically an all-fiber ring laser in which the delay line constitutes part of the ring. Another part of the ring - the laser gain medium - is an erbium-doped fiber amplifier pumped by a diode laser at a wavelength of 980 nm. The loop also includes an optical isolator, two polarization controllers, and a polarizing beam splitter. The optical isolator enforces unidirectional lasing. The polarization beam splitter allows light in only one polarization mode to pass through the ring; light in the orthogonal polarization mode is rejected from the ring and utilized as a diagnostic output, which is fed to an optical spectrum analyzer and a photodetector. The photodetector output is fed to a radio-frequency spectrum analyzer and an oscilloscope. The fiber ring laser can generate continuous-wave radiation in non-mode-locked operation or ultrashort optical pulses in mode-locked operation. The mode-locked operation exhibited by this ring is said to be passive in the sense that no electro-optical modulator or other active optical component is used to achieve it. Passive mode locking is achieved by exploiting optical nonlinearity of passive components in such a manner as to obtain ultra-short optical pulses. In this setup, the particular nonlinear optical property exploited to achieve passive mode locking is nonlinear polarization rotation. This or any ring laser can support oscillation in multiple modes as long as sufficient gain is present to overcome

  4. Optics of Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII): Delay Lines and Alignment

    Science.gov (United States)

    Dhabal, Arnab; Rinehart, Stephen A.; Rizzo, Maxime J.; Mundy, Lee; Fixsen, Dale; Sampler, Henry; Mentzell, Eric; Veach, Todd; Silverberg, Robert F.; Furst, Stephen; hide

    2016-01-01

    We present the optics of Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII) as it gets ready for launch. BETTII is an 8-meter baseline far-infrared (30-90 microns) interferometer mission with capabilities of spatially resolved spectroscopy aimed at studying star formation and galaxy evolution. The instrument collects light from its two arms, makes them interfere, divides them into two science channels (30-50 microns and 60-90 microns), and focuses them onto the detectors. It also separates out the NIR light (1-2.5 microns) and uses it for tip-tilt corrections of the telescope pointing. Currently, all the optical elements have been fabricated, heat treated, coated appropriately and are mounted on their respective assemblies. We are presenting the optical design challenges for such a balloon borne spatio-spectral interferometer, and discuss how they have been mitigated. The warm and cold delay lines are an important part of this optics train. The warm delay line corrects for path length differences between the left and the right arm due to balloon pendulation, while the cold delay line is aimed at introducing a systematic path length difference, thereby generating our interferograms from where we can derive information about the spectra. The details of their design and the results of the testing of these opto-mechanical parts are also discussed. The sensitivities of different optical elements on the interferograms produced have been determined with the help of simulations using FRED software package. Accordingly, an alignment plan is drawn up which makes use of a laser tracker, a CMM, theodolites and a LUPI interferometer.

  5. Coagulation sensors based on magnetostrictive delay lines for biomedical and chemical engineering applications

    International Nuclear Information System (INIS)

    Maliaritsi, E.; Zoumpoulakis, L.; Simitzis, J.; Vassiliou, P.; Hristoforou, E.

    2006-01-01

    Coagulation sensors based on the magnetostrictive delay line technique are presented in this paper. They are based on magnetostrictive ribbons and are used for measuring the coagulation, curing or solidification time of different liquids. Experimental results indicate that the presented sensing elements can determine the blood coagulation with remarkable repeatability, thus allowing their use as blood coagulation sensors. Additionally, results indicate that they can also measure curing time of resins, solidification of fluids and coagulation of chemical substances, therefore allowing their implementation in chemical engineering applications

  6. A Neutron Sensitive Microchannel Plate Detector with Cross Delay Line Readout

    International Nuclear Information System (INIS)

    Berry, Kevin D.; Bilheux, Hassina Z.; Crow, Lowell; Diawara, Yacouba; Feller, W. Bruce; Iverson, Erik B.; Martin, Adrian; Robertson, J. Lee

    2012-01-01

    Microchannel plates containing neutron absorbing elements such as boron and gadolinium in the bulk glass are used as the sensing element in high spatial resolution, high rate neutron imaging systems. In this paper we describe one such device, using both 10 B and natural Gd, which employs cross delay line signal readout, with time-of-flight capability. This detector has a measured spatial resolution under 40 m FWHM, thermal neutron efficiency of 19%, and has recorded rates in excess of 500 kHz. A physical and functional description is presented, followed by a discussion of measurements of detector performance and a brief survey of some practical applications.

  7. Optical Time Division Switching Using Multiple Stages of Fiber Optic Delay Lines.

    Science.gov (United States)

    Spanke, Ronald Anthony

    Optical Time Slot Interchanges (OTSIs) can be realized by guided wave LiNbO_3 optical switches performing space division switching of optical fiber delay lines. In this dissertation the problems of reducing the total length of fiber required and also of improving the SNR characteristics of this OTSI function are addressed. Several new OTSI architectures are proposed to reduce the total fiber length while still obtaining excellent SNR characteristics. These reduced fiber architectures include the Distributed Input Delay, Distributed Output Delay, the 2-Stage decomposition and the Distributed Input/Output Delay architectures. A Parallel Feedback (PFB) OTSI architecture is proposed that achieves the theoretical minimum number of delay fibers and the theoretical minimum total length of delay fiber for a given OTSI function. Broadcast OTSI architectures are proposed that enable the data in an incoming time slot to be broadcast to one or more outgoing time slots. These broadcast OTSI architectures include the Time-Dup-Time (TDT) system, Passive Splitter/Active Combiner (PS/AC) equivalents of the point -to-point reduced fiber architectures, and the broadcast PFB architecture. For each of the point-to-point and the broadcast OTSI architectures proposed, a detailed characterization of the architecture is performed including an analysis of number of fibers, total fiber length, number of optical switches and drivers, attenuation and SNR characteristics. This dissertation also proposes several new techniques for improving the system SNR and for calibration of the OTSI architectures. A cascaded noise reduction and a differential attenuation compensation technique are used to achieve a significantly higher system SNR at the output of the OTSI. In-situ calibration techniques are discussed to determine the optimum operating voltages for the LiNbO _3 switches when alternating between states every time slot. These techniques attempt to compensate for an output power drift problem

  8. 75 FR 78928 - Limited Service Domestic Voyage Load Lines for River Barges on Lake Michigan, Delay of Effective...

    Science.gov (United States)

    2010-12-17

    ...-AA17 Limited Service Domestic Voyage Load Lines for River Barges on Lake Michigan, Delay of Effective Date AGENCY: Coast Guard, DHS. ACTION: Notice of delay of effective date and reopening of the comment... 46 CFR part 45 as amended by the final rule published in the November 18, 2010, Federal Register (75...

  9. Ultra-Wide Band Non-reciprocity through Sequentially-Switched Delay Lines.

    Science.gov (United States)

    Biedka, Mathew M; Zhu, Rui; Xu, Qiang Mark; Wang, Yuanxun Ethan

    2017-01-06

    Achieving non-reciprocity through unconventional methods without the use of magnetic material has recently become a subject of great interest. Towards this goal a time switching strategy known as the Sequentially-Switched Delay Line (SSDL) is proposed. The essential SSDL configuration consists of six transmission lines of equal length, along with five switches. Each switch is turned on and off sequentially to distribute and route the propagating electromagnetic wave, allowing for simultaneous transmission and receiving of signals through the device. Preliminary experimental results with commercial off the shelf parts are presented which demonstrated non-reciprocal behavior with greater than 40 dB isolation from 200 KHz to 200 MHz. The theory and experimental results demonstrated that the SSDL concept may lead to future on-chip circulators over multi-octaves of frequency.

  10. Photonic-assisted time-interleaved ADC based on optical delay line

    International Nuclear Information System (INIS)

    Xu, Chen; Zheng, Shilie; Chen, Xinyi; Chi, Hao; Jin, Xiaofeng; Zhang, Xianmin

    2016-01-01

    An approach to implement photonic-assisted time-interleaved analog-to-digital conversion and its calibration method are presented. The analog modulated optical signal is divided into M channels, suffering different time delay induced by optical delay lines which provide great flexibility in producing time intervals and is then sampled by electronic analog-to-digital converters (ADCs). The channel mismatches resulting in performance degradation are estimated by a modified sine wave fitting method. The time mismatch and other mismatches are corrected by fine optical delay adjustment and digital processing, respectively. A four-channel photonic-assisted time-interleaved analog-to-digital converter (TIADC) system operating at 40 GSa s −1 was demonstrated experimentally. The photonic-assisted TIADC system was tested with a 6.31 GHz sine wave signal, exhibiting 40.3 dB signal-to-noise and distortion ratio (SINAD) and 57.6 dBc spurious-free dynamic range (SFDR). It is shown that the SINAD is dominated by the signal-to-noise ratio (SNR) of the analog optical link and the SFDR of the proposed system is limited by the linearity of the link. (paper)

  11. A liquid lens switching-based motionless variable fiber-optic delay line

    Science.gov (United States)

    Khwaja, Tariq Shamim; Reza, Syed Azer; Sheikh, Mumtaz

    2018-05-01

    We present a Variable Fiber-Optic Delay Line (VFODL) module capable of imparting long variable delays by switching an input optical/RF signal between Single Mode Fiber (SMF) patch cords of different lengths through a pair of Electronically Controlled Tunable Lenses (ECTLs) resulting in a polarization-independent operation. Depending on intended application, the lengths of the SMFs can be chosen accordingly to achieve the desired VFODL operation dynamic range. If so desired, the state of the input signal polarization can be preserved with the use of commercially available polarization-independent ECTLs along with polarization-maintaining SMFs (PM-SMFs), resulting in an output polarization that is identical to the input. An ECTL-based design also improves power consumption and repeatability. The delay switching mechanism is electronically-controlled, involves no bulk moving parts, and can be fully-automated. The VFODL module is compact due to the use of small optical components and SMFs that can be packaged compactly.

  12. Clock-frequency and temperature margins of a high-temperature superconductor delay-line memory

    International Nuclear Information System (INIS)

    Hattori, W.; Tahara, S.

    1999-01-01

    We have developed a 10 GHz 32-bit delay-line memory, using a semiconductor crossbar switch and a YBa 2 Cu 3 O 7-δ coplanar delay line. For use in the high-speed (≥10 GHz) cell-buffer storage of large-throughput (≥1 Tbit/s) asynchronous transfer mode (ATM) switching systems, this memory must be fairly reliable. To evaluate the reliability of the operation, therefore, we measured the clock-frequency and temperature margins and the temperature dependence of the bit-error rate. At 64 K, this memory has a capacity of 32 bits with a clock frequency of 9.89±0.11 GHz. In general, clock frequencies of communication systems are strictly managed so that the margins are less than 10 -6 . Therefore, the frequency margin of this memory (∼2x10 -2 )) is wide enough for use in communication systems. The temperature margin was 71.5±4.3 K at 10 GHz and 33 bits. This memory offered error-free operation (BER -13 ) at 71.5 ±3.5 K. These temperature margins are wide enough to be controlled by a cryocooler. These results show that the memory offers reliability and that it can be applied to high-speed ATM cell-buffer storage. (author)

  13. Peculiar time dependence of unexpected lines in delayed beam-foil X-ray spectra of V, Fe and Ni

    International Nuclear Information System (INIS)

    Ahmad, Nissar; Karn, Ranjeet K.; Marketos, Pan; Nandi, T.

    2005-01-01

    Delayed beam-foil X-ray spectra of highly charged ions of V, Fe and Ni show a few lines at energies higher than the H-like Lyman α-line of the respective projectile ions. These can only be attributed to heavier ions. Further the time dependence of such unexpected lines display a peculiar behavior. This work presents the experimental observations systematically

  14. Four-deep charge-time and pulse-width scaling discriminator for delay line MWPC's

    International Nuclear Information System (INIS)

    Lee, K.L.; Kirsten, F.A.; Grigorian, A.; Guiragossian, Z.G.T.

    1976-01-01

    A discriminator has been developed for digitizing both intercepted total charge and location of electromagnetic shower and particle trajectories in multi-wire proportional chambers read by delay lines. Determination of shower trajectory is aided by video signal integration followed by centroid-locating discrimination. Calibrated run-down of the signal integrating capacitor gives the charge information above a given threshold level. The discriminator is designed to handle up to four shower-induced video signals per event by incorporating steering circuits within the module. Each video signal is examined for time over an adjustable threshold. Video pulses with separation of less than 20 nsec are treated as a single pulse. Counter-logic circuits indicate the number of video signals digitized. These signal processing circuits provide a first level of data sifting which otherwise must be carried out with additional discriminator channels and added complexity in data recognition

  15. Dynamic measurements at THz frequencies with a fast rotary delay line

    Science.gov (United States)

    Guerboukha, Hichem; Markov, Andrey; Qu, Hang; Skorobogatiy, Maksim

    2016-02-01

    Fabrication, characterization, and applications of a fast rotary linear optical delay line (FRLODL) for THz time-domain spectroscopy are presented. The FRLODL features two reflective surfaces with spatially separated incoming and outgoing beams. It has been manufactured using CNC machining. A linear dependence of the optical delay on the rotation angle allows a straightforward extraction of the conversion factor between the acquisition time (in ms) and the terahertz pulse time (in ps). The FRLODL has been tested using rotation speeds of up to 48 Hz, corresponding to an acquisition rate of up to 192 Hz with four blades incorporated on the same disk. At high speeds we observe a decrease of the bandwidth due to the limitations of the electronics, in particular, the transimpedance amplifier. An error analysis is performed by experimentally evaluating the signal-to-noise ratio and the dynamic range. With regard to the applications of the FRLODL, we first present observation of the evaporation of liquids, namely water, acetone and methanol. We then demonstrate monitoring of the spray painting process. Finally, detection of fast moving objects at 1 m/s and their thickness characterization are presented.

  16. Nuclei far from the beta stability line. High-energy beta decay and delayed-particle emission

    International Nuclear Information System (INIS)

    Hansen, R.G.; Hornshj, P.

    1976-01-01

    Progress in on-line mass separation together with improved proton accelerators now permit the production of secondary ion-beams of the order of 10 11 atoms per second. Applications to the study of delayed-proton and delayed-alpha emission are discussed. These effects have been used for the estimation of alpha-emission strength functions at 4-6 MeV excitation energy, and for the determination of level densities through fluctuation analysis

  17. THE STRUCTURE OF THE BROAD-LINE REGION IN ACTIVE GALACTIC NUCLEI. I. RECONSTRUCTED VELOCITY-DELAY MAPS

    International Nuclear Information System (INIS)

    Grier, C. J.; Peterson, B. M.; Pogge, R. W.; De Rosa, G.; Martini, Paul; Kochanek, C. S.; Zu, Y.; Shappee, B.; Beatty, T. G.; Salvo, C. Araya; Bird, J. C.; Horne, Keith; Bentz, M. C.; Denney, K. D.; Siverd, R.; Sergeev, S. G.; Borman, G. A.; Kaspi, S.; Bord, D. J.; Che, X.

    2013-01-01

    We present velocity-resolved reverberation results for five active galactic nuclei. We recovered velocity-delay maps using the maximum entropy method for four objects: Mrk 335, Mrk 1501, 3C 120, and PG 2130+099. For the fifth, Mrk 6, we were only able to measure mean time delays in different velocity bins of the Hβ emission line. The four velocity-delay maps show unique dynamical signatures for each object. For 3C 120, the Balmer lines show kinematic signatures consistent with both an inclined disk and infalling gas, but the He II λ4686 emission line is suggestive only of inflow. The Balmer lines in Mrk 335, Mrk 1501, and PG 2130+099 show signs of infalling gas, but the He II emission in Mrk 335 is consistent with an inclined disk. We also see tentative evidence of combined virial motion and infalling gas from the velocity-binned analysis of Mrk 6. The maps for 3C 120 and Mrk 335 are two of the most clearly defined velocity-delay maps to date. These maps constitute a large increase in the number of objects for which we have resolved velocity-delay maps and provide evidence supporting the reliability of reverberation-based black hole mass measurements.

  18. THE STRUCTURE OF THE BROAD-LINE REGION IN ACTIVE GALACTIC NUCLEI. I. RECONSTRUCTED VELOCITY-DELAY MAPS

    Energy Technology Data Exchange (ETDEWEB)

    Grier, C. J.; Peterson, B. M.; Pogge, R. W.; De Rosa, G.; Martini, Paul; Kochanek, C. S.; Zu, Y.; Shappee, B.; Beatty, T. G.; Salvo, C. Araya; Bird, J. C. [Department of Astronomy, The Ohio State University, 140 W 18th Ave, Columbus, OH 43210 (United States); Horne, Keith [SUPA Physics and Astronomy, University of St. Andrews, Fife, KY16 9SS Scotland (United Kingdom); Bentz, M. C. [Department of Physics and Astronomy, Georgia State University, Astronomy Offices, One Park Place South SE, Suite 700, Atlanta, GA 30303 (United States); Denney, K. D. [Marie Curie Fellow at the Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Siverd, R. [Department of Physics and Astronomy, Vanderbilt University, 5301 Stevenson Center, Nashville, TN 37235 (United States); Sergeev, S. G.; Borman, G. A. [Crimean Astrophysical Observatory, P/O Nauchny Crimea 98409 (Ukraine); Kaspi, S. [School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978 (Israel); Bord, D. J. [Department of Natural Sciences, The University of Michigan - Dearborn, 4901 Evergreen Rd, Dearborn, MI 48128 (United States); Che, X. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 41809 (United States); and others

    2013-02-10

    We present velocity-resolved reverberation results for five active galactic nuclei. We recovered velocity-delay maps using the maximum entropy method for four objects: Mrk 335, Mrk 1501, 3C 120, and PG 2130+099. For the fifth, Mrk 6, we were only able to measure mean time delays in different velocity bins of the H{beta} emission line. The four velocity-delay maps show unique dynamical signatures for each object. For 3C 120, the Balmer lines show kinematic signatures consistent with both an inclined disk and infalling gas, but the He II {lambda}4686 emission line is suggestive only of inflow. The Balmer lines in Mrk 335, Mrk 1501, and PG 2130+099 show signs of infalling gas, but the He II emission in Mrk 335 is consistent with an inclined disk. We also see tentative evidence of combined virial motion and infalling gas from the velocity-binned analysis of Mrk 6. The maps for 3C 120 and Mrk 335 are two of the most clearly defined velocity-delay maps to date. These maps constitute a large increase in the number of objects for which we have resolved velocity-delay maps and provide evidence supporting the reliability of reverberation-based black hole mass measurements.

  19. A self contained Linux based data acquisition system for 2D detectors with delay line readout

    International Nuclear Information System (INIS)

    Beltran, D.; Toledo, J.; Klora, A.C.; Ramos-Lerate, I.; Martinez, J.C.

    2007-01-01

    This article describes a fast and self-contained data acquisition system for 2D gas-filled detectors with delay line readout. It allows the realization of time resolved experiments in the millisecond scale. The acquisition system comprises of an industrial PC running Linux, a commercial time-to-digital converter and an in-house developed histogramming PCI card. The PC provides a mass storage for images and a graphical user interface for system monitoring and control. The histogramming card builds images with a maximum count rate of 5 MHz limited by the time-to-digital converter. Histograms are transferred to the PC at 85 MB/s. This card also includes a time frame generator, a calibration channel unit and eight digital outputs for experiment control. The control software was developed for easy integration into a beamline, including scans. The system is fully operational at the Spanish beamline BM16 at the ESRF in France, the neutron beamlines Adam and Eva at the ILL in France, the Max Plank Institute in Stuttgart in Germany, the University of Copenhagen in Denmark and at the future ALBA synchrotron in Spain. Some representative collected images from synchrotron and neutron beamlines are presented

  20. [Effects of allitridum on rapidly delayed rectifier potassium current in HEK293 cell line].

    Science.gov (United States)

    Zhang, Jiancheng; Lin, Kun; Wei, Zhixiong; Chen, Qian; Liu, Li; Zhao, Xiaojing; Zhao, Ying; Xu, Bin; Chen, Xi; Li, Yang

    2015-08-01

    To study the effect of allitridum on rapidly delayed rectifier potassium current (IKr) in HEK293 cell line. HEK293 cells were transiently transfected with HERG channel cDNA plasmid pcDNA3.1 via Lipofectamine. Allitridum was added to the extracellular solution by partial perfusion after giga seal at the final concentration of 30 µmol/L. Whole-cell patch clamp technique was used to record the HERG currents and gating kinetics before and after allitridum exposure at room temperature. The amplitude and density of IHERG were both suppressed by allitridum in a voltage-dependent manner. In the presence of allitridum, the peak current of IHERG was reduced from 73.5∓4.3 pA/pF to 42.1∓3.6 pA/pF at the test potential of +50 mV (P<0.01). Allitridum also concentration-dependently decreased the density of the IHERG. The IC50 of allitridum was 34.74 µmol/L with a Hill coefficient of 1.01. Allitridum at 30 µmol/L caused a significant positive shift of the steady-state activation curve of IHERG and a markedly negative shift of the steady-state inactivation of IHERG, and significantly shortened the slow time constants of IHERG deactivation. Allitridum can potently block IHERG in HEK293 cells, which might be the electrophysiological basis for its anti-arrhythmic action.

  1. Micromachined silicon acoustic delay line with 3D-printed micro linkers and tapered input for improved structural stability and acoustic directivity

    International Nuclear Information System (INIS)

    Cho, Y; Kumar, A; Xu, S; Zou, J

    2016-01-01

    Recent studies have shown that micromachined silicon acoustic delay lines can provide a promising solution to achieve real-time photoacoustic tomography without the need for complex transducer arrays and data acquisition electronics. To achieve deeper imaging depth and wider field of view, a longer delay time and therefore delay length are required. However, as the length of the delay line increases, it becomes more vulnerable to structural instability due to reduced mechanical stiffness. In this paper, we report the design, fabrication, and testing of a new silicon acoustic delay line enhanced with 3D printed polymer micro linker structures. First, mechanical deformation of the silicon acoustic delay line (with and without linker structures) under gravity was simulated by using finite element method. Second, the acoustic crosstalk and acoustic attenuation caused by the polymer micro linker structures were evaluated with both numerical simulation and ultrasound transmission testing. The result shows that the use of the polymer micro linker structures significantly improves the structural stability of the silicon acoustic delay lines without creating additional acoustic attenuation and crosstalk. In addition, the improvement of the acoustic acceptance angle of the silicon acoustic delay lines was also investigated to better suppress the reception of unwanted ultrasound signals outside of the imaging plane. These two improvements are expected to provide an effective solution to eliminate current limitations on the achievable acoustic delay time and out-of-plane imaging resolution of micromachined silicon acoustic delay line arrays. (paper)

  2. Testing Delays Resulting in Increased Identification Accuracy in Line-Ups and Show-Ups.

    Science.gov (United States)

    Dekle, Dawn J.

    1997-01-01

    Investigated time delays (immediate, two-three days, one week) between viewing a staged theft and attempting an eyewitness identification. Compared lineups to one-person showups in a laboratory analogue involving 412 subjects. Results show that across all time delays, participants maintained a higher identification accuracy with the showup…

  3. Advanced materials for the optical delay line of frequency pulse modulator on the basis of semiconductor laser

    International Nuclear Information System (INIS)

    Abrarov, S.M.

    1999-01-01

    In the paper some materials which can be sued as an optical delay line of the pulse frequency modulator are considered. The structure and the principle are described as a modulator consisting of a laser diode with two Fabry Perot resonators and an optical wave guide providing a feedback loop. The optical wave guide fulfills the function of delay line and links the two resonators. The pulse sequence of the radiation of the semiconductor laser arises due to failure and recovery of optical generation. The pulse frequency modulation can be carried out by the action of electrical tension field on the electro optic martial of the wave guide. The selection of three electro-optic crystals for making of the optical wave guide of the considered modulator is justified. (author)

  4. Graphene-based fine-tunable optical delay line for optical beamforming in phased-array antennas.

    Science.gov (United States)

    Tatoli, Teresa; Conteduca, Donato; Dell'Olio, Francesco; Ciminelli, Caterina; Armenise, Mario N

    2016-06-01

    The design of an integrated graphene-based fine-tunable optical delay line on silicon nitride for optical beamforming in phased-array antennas is reported. A high value of the optical delay time (τg=920  ps) together with a compact footprint (4.15  mm2) and optical loss graphene-based Mach-Zehnder interferometer switches and two vertically stacked microring resonators between which a graphene capacitor is placed. The tuning range is obtained by varying the value of the voltage applied to the graphene electrodes, which controls the optical path of the light propagation and therefore the delay time. The graphene provides a faster reconfigurable time and low values of energy dissipation. Such significant advantages, together with a negligible beam-squint effect, allow us to overcome the limitations of conventional RF beamformers. A highly efficient fine-tunable optical delay line for the beamsteering of 20 radiating elements up to ±20° in the azimuth direction of a tile in a phased-array antenna of an X-band synthetic aperture radar has been designed.

  5. Printed low velocity delay lines for cathode readout of proportional chambers

    International Nuclear Information System (INIS)

    Bosshard, R.; Chase, R.L.; Fischer, J.; Radeka, V.

    1974-01-01

    A readout which simultaneously insures a correct electric field, a satisfactory induced signal, the delay function itself, and low particle scattering is described for multiwire proportional chambers. (U.S.)

  6. Elimination of residual amplitude modulation in tunable diode laser wavelength modulation spectroscopy using an optical fiber delay line.

    Science.gov (United States)

    Chakraborty, Arup Lal; Ruxton, Keith; Johnstone, Walter; Lengden, Michael; Duffin, Kevin

    2009-06-08

    A new fiber-optic technique to eliminate residual amplitude modulation in tunable diode laser wavelength modulation spectroscopy is presented. The modulated laser output is split to pass in parallel through the gas measurement cell and an optical fiber delay line, with the modulation frequency / delay chosen to introduce a relative phase shift of pi between them. The two signals are balanced using a variable attenuator and recombined through a fiber coupler. In the absence of gas, the direct laser intensity modulation cancels, thereby eliminating the high background. The presence of gas induces a concentration-dependent imbalance at the coupler's output from which the absolute absorption profile is directly recovered with high accuracy using 1f detection.

  7. Nucleolar re-activation is delayed in mouse embryos cloned from two different cell lines

    DEFF Research Database (Denmark)

    Svarcova, Olga; Dinnyes, A.; Polgar, Z.

    2009-01-01

    displayed early NPBs transformation. In conclusion, despite normal onset of EGA in cloned embryos, activation of functional nucleoli was one cell cycle delayed in NT embryos. NT-MEF embryos displayed normal targeting but delayed activation of nucleolar proteins. Contrary, in NT-HM1 embryos, both......Aim of this study was to evaluate and compare embryonic genome activation (EGA) in mouse embryos of different origin using nucleolus as a marker. Early and late 2-cell and late 4-cell stage embryos, prepared by in vitro fertilization (IVF), parthenogenetic activation (PG), and nuclear transfer...... ofmouse embryonic fibroblast (MEF) and mouse HM1 emryonic stem cells (HM1), were processed for autoradiography following 3H-uridine incubation (transcriptional activity), transmission electron microscopy (ultrastructure) and immunofluorescence (nucleolar proteins; upstream binding factor, UBF...

  8. A Design of First-Order Delay-Line DPLL in 1.2μm CMOS Technology

    OpenAIRE

    Seki, Ikuo; Nakashi, Kenichi; Ushida, Mitsuhiko; Taniguchi, Kenji

    1996-01-01

    This paper describes a CMOS 1st-order delay-line DPLL in l.2μm technology for clock regeneration. We have employed a parallel-architecture PC (Phase Comparator) to improve the speed and a DCO (Digitally Controlled Oscillator) without timing hazard. And we have also laid it out in 1.2μm CMOS, and simulated its performance by SPICE as well as logic simulation. Results show that the DPLL operates up to 60MHz, and that lock-in ranges are +5/-5% for regular" 10" input and +5/-5% for 2^13-1 PRBS (P...

  9. The Impact of Delays of Freight Trains in JIT System on Example One Track Line

    Directory of Open Access Journals (Sweden)

    Dlugoš Matúš

    2017-01-01

    Full Text Available The paper describes the problem between freight trains operated by Metrans Danube, a.s. and passenger trains operated by Regiojet, a.s on the line Bratislava – Dunajská Streda - Komárno. It is very important to emphasize this problem because, nowadays, mostly freight trains across the Europe drive in just in time system, it means, that shipments are delivered at exact time and place on time. At this line there are many problems not only this track line is single track, so it is necessary to cross the trains very often in traffic points which maximum 2 traffic tracks but also organizing of transport is more complicated which is provided by Railway infrastructure manager – this case is very important example when railway traffic technology slows down all processes in the logistic chain.

  10. Irradiation combined with SU5416: Microvascular changes and growth delay in a human xenograft glioblastoma tumor line

    International Nuclear Information System (INIS)

    Schuuring, Janneke; Bussink, Johan; Bernsen, Hans; Peeters, Wenny; Kogel, Albert J. van der

    2005-01-01

    Purpose: The combination of irradiation and the antiangiogenic compound SU5416 was tested and compared with irradiation alone in a human glioblastoma tumor line xenografted in nude mice. The aim of this study was to monitor microenvironmental changes and growth delay. Methods and materials: A human glioblastoma xenograft tumor line was implanted in nude mice. Irradiations consisted of 10 Gy or 20 Gy with and without SU5416. Several microenvironmental parameters (tumor cell hypoxia, tumor blood perfusion, vascular volume, and microvascular density) were analyzed after imunohistochemical staining. Tumor growth delay was monitored for up to 200 days after treatment. Results: SU5416, when combined with irradiation, has an additive effect over treatment with irradiation alone. Analysis of the tumor microenvironment showed a decreased vascular density during treatment with SU5416. In tumors regrowing after reaching only a partial remission, vascular characteristics normalized shortly after cessation of SU5416. However, in tumors regrowing after reaching a complete remission, permanent microenvironmental changes and an increase of tumor necrosis with a subsequent slower tumor regrowth was found. Conclusions: Permanent vascular changes were seen after combined treatment resulting in complete remission. Antiangiogenic treatment with SU5416 when combined with irradiation has an additive effect over treatment with irradiation or antiangiogenic treatment alone

  11. ESTIMATION OF BURSTS LENGTH AND DESIGN OF A FIBER DELAY LINE BASED OBS ROUTER

    Directory of Open Access Journals (Sweden)

    RICHA AWASTHI

    2017-03-01

    Full Text Available The demand for higher bandwidth is increasing day by day and this ever growing demand cannot be catered to with current electronic technology. Thus new communication technology like optical communication needs to be used. In the similar context OBS (optical burst switching is considered as next generation data transfer technology. In OBS information is transmitted in forms of optical bursts of variable lengths. However, contention among the bursts is a major problem in OBS system, and for contention resolution defection routing is mostly preferred. However, deflection routing increases delay. In this paper, it is shown that the arrival of very large bursts is rare event, and for moderate burst length the buffering of contending burst can provide very effective solution. However, in case of arrival of large bursts deflection can be used.

  12. A MWPC with a cathode coupled delay line read-out as radioactivity detector for DNA repair studies

    International Nuclear Information System (INIS)

    Bellazzini, R.; Del Guerra, A.; Massai, M.M.; Ragadini, M.; Spandre, G.; Tonelli, G.

    1981-01-01

    A non selective method for the isolation of DNA repair-deficient mutants in mammalian cells is discussed. The method requires radioactive labelling of the short DNA sequences synthesized during repair of damaged regions. Mutants should be recognized by the absence of radioactive incorporation into their DNA. A multiwire proportional chamber (MWPC) is proposed as a suitable radioactivity detector. The performance of a MWPC prototype with a cathode coupled delay line read-out is described and is shown to be adequate for this application. The main advantages of a MWPC are reviewed with respect to other methods used for β - radioactivity counting of biological samples, such as liquid scintillators or autoradiography: the proposed detection method is non destructive for the cells, which are being kept alive for further biological studies, furthermore many cell clones can be screened within a reasonable time. (orig.)

  13. Wavelength-stepped, actively mode-locked fiber laser based on wavelength-division-multiplexed optical delay lines

    Science.gov (United States)

    Lee, Eunjoo; Kim, Byoung Yoon

    2017-12-01

    We propose a new scheme for an actively mode-locked wavelength-swept fiber laser that produces a train of discretely wavelength-stepped pulses from a short fiber cavity. Pulses with different wavelengths are split and combined by standard wavelength division multiplexers with fiber delay lines. As a proof of concept, we demonstrate a laser using an erbium doped fiber amplifier and commercially available wavelength-division multiplexers with wavelength spacing of 0.8 nm. The results show simultaneous mode-locking at three different wavelengths. Laser output parameters in time domain, optical and radio frequency spectral domain, and the noise characteristics are presented. Suggestions for the improved design are discussed.

  14. A hemispherical photoelectron spectrometer with 2-dimensional delay-line detector and integrated spin-polarization analysis

    International Nuclear Information System (INIS)

    Plucinski, L.; Oelsner, A.; Matthes, F.; Schneider, C.M.

    2010-01-01

    Photoelectron spectrometers usually allow detection of either spin-resolved energy-distribution curves (EDCs) at single emission angle, or 2D angle-vs.-energy images without spin-resolution. We have combined the two detection schemes into one spectrometer system which permits simultaneous detection of a 1D spin-resolved EDC and a 2D angular map. A state-of-the-art hemispherical analyzer is used as an energy filter. Its original scintillator detector has been replaced by a delay-line-detector (DLD), and part of the electron beam is allowed to pass through to reach the spin-polarized low energy electron diffraction (SPLEED) spin-detector mounted subsequently. The electron-optics between DLD and SPLEED contains a 90 o deflector to feature simultaneous detection of in-plane and out-of-plane spin components. These electron-optics have been optimized for high transmission to reduce acquisition times in the spin-resolved mode.

  15. Picosecond wide-field time-correlated single photon counting fluorescence microscopy with a delay line anode detector

    Energy Technology Data Exchange (ETDEWEB)

    Hirvonen, Liisa M.; Le Marois, Alix; Suhling, Klaus, E-mail: klaus.suhling@kcl.ac.uk [Department of Physics, King' s College London, Strand, London WC2R 2LS (United Kingdom); Becker, Wolfgang; Smietana, Stefan [Becker & Hickl GmbH, Nahmitzer Damm 30, 12277 Berlin (Germany); Milnes, James; Conneely, Thomas [Photek Ltd., 26 Castleham Rd, Saint Leonards-on-Sea TN38 9NS (United Kingdom); Jagutzki, Ottmar [Institut für Kernphysik, Max-von-Laue-Str. 1, 60438 Frankfurt (Germany)

    2016-08-15

    We perform wide-field time-correlated single photon counting-based fluorescence lifetime imaging (FLIM) with a crossed delay line anode image intensifier, where the pulse propagation time yields the photon position. This microchannel plate-based detector was read out with conventional fast timing electronics and mounted on a fluorescence microscope with total internal reflection (TIR) illumination. The picosecond time resolution of this detection system combines low illumination intensity of microwatts with wide-field data collection. This is ideal for fluorescence lifetime imaging of cell membranes using TIR. We show that fluorescence lifetime images of living HeLa cells stained with membrane dye di-4-ANEPPDHQ exhibit a reduced lifetime near the coverslip in TIR compared to epifluorescence FLIM.

  16. On the impact of fiber-delay-lines (FDL) in an all-optical network (AON) bottleneck without wavelength conversion

    Science.gov (United States)

    Argibay-Losada, Pablo Jesus; Sahin, Gokhan

    2014-08-01

    Random access memories (RAM) are fundamental in conventional electronic switches and routers to manage short-term congestion and to decrease data loss probabilities. Switches in all-optical networks (AONs), however, do not have access to optical RAM, and therefore are prone to much higher loss levels than their electronic counterparts. Fiber-delay-lines (FDLs), able to delay an optical data packet a fixed amount of time, have been proposed in the literature as a means to alleviate those high loss levels. However, they are extremely bulky to manage, so their usage introduces a trade-off between practicality and performance in the design and operation of the AON. In this paper we study the influence that FDLs have in the performance of flows crossing an all-optical switch that acts as their bottleneck. We show how extremely low numbers of FDLs (e.g., 1 or 2) can help in reducing losses by several orders of magnitude in several illustrative scenarios with high aggregation levels. Our results therefore suggest that FDLs can be a practical means of dealing with congestion in AONs in the absence of optical RAM buffers or of suitable data interchange protocols specifically designed for AONs.

  17. Radiological engineering evaluation of the delay time line air scrubber located at the Clinton P. Anderson Meson Physics Facility (LAMPF)

    International Nuclear Information System (INIS)

    Huneycutt, S.E.

    1996-05-01

    The purpose of this study was to determine the effects of the addition of an air scrubber to an already existing delay line and whether it would scrub 11 CO 2 . There were three main objectives of this study. The first objective was to determine the scrubbing efficiency of the scrubber. The scrubbing efficiency was then used to predict the dose rates in the scrubber area and compare those values with measurements from radiological surveys. The third objective was to determine if the shield blocks were effective in reducing the dose rates in the scrubber area. The activities were measured before and during scrubber operation and this information was used to calculate the scrubbing efficiency and the efficiency of 11 CO 2 removal was determined to be around 50%. Microshield was then used to predict dose rates and compared those values with measurements from radiological surveys. This was also used to determine the that the shield blocks around the scrubber were effective in reducing the dose rates from the radiation field produced by the radionuclides in the scrubber

  18. The structure of the broad-line region in active galactic nuclei. I. Reconstructed velocity-delay maps

    DEFF Research Database (Denmark)

    Grier, C.J.; Peterson, B.M.; Pogge, R.W.

    2013-01-01

    We present velocity-resolved reverberation results for five active galactic nuclei. We recovered velocity-delay maps using the maximum entropy method for four objects: Mrk 335, Mrk 1501, 3C 120, and PG 2130+099. For the fifth, Mrk 6, we were only able to measure mean time delays in different velo...

  19. The MEL-X project at the Lawrence Livermore National Laboratory: a mirror-based delay line for x-rays

    Science.gov (United States)

    Pardini, Tom; Hill, Randy; Decker, Todd; Alameda, Jennifer; Soufli, Regina; Aquila, Andy; Guillet, Serge; Boutet, Sébastien; Hau-Riege, Stefan P.

    2015-09-01

    At the Lawrence Livermore National Laboratory (LLNL) in collaboration with the Linac Coherent Light Source (LCLS) we are developing a mirror-based delay line for x-rays (MEL-X) to enable x-ray pump/x-ray probe experiments at Free Electron Lasers (XFELs). The goal of this project is the development and deployment of a proof-of-principle delay line featuring coated x-ray optics. The four-mirror design of the MEL-X is motivated by the need for ease of alignment and use. In order to simplify the overlap of the pump and the probe beam after each delay time change, a scheme involving super-polished rails and mirror-to-motor decoupling has been adopted. The MEL-X, used in combination with a bright pulsed source like LCLS, features a capability for a high intensity pump beam. Its Iridium coating allows it to work at hard x-ray energies all the way up to 9 keV, with a probe beam transmission of 35% up to 8keV, and 14% at 9keV. The delay time can be tailored to each particular experiment, with a nominal range of 70 - 350 fs for this prototype. The MEL-X, combined with established techniques such as x-ray diffraction, absorption or emission, could provide new insights on ultra-fast transitions in highly excited states of matter.

  20. Seed Nutrition and Quality, Seed Coat Boron and Lignin Are Influenced by Delayed Harvest in Exotically-Derived Soybean Breeding Lines under High Heat.

    Science.gov (United States)

    Bellaloui, Nacer; Smith, James R; Mengistu, Alemu

    2017-01-01

    The timing of harvest is a major factor affecting seed quality in soybean, particularly in Midsouthern USA, when rain during harvest period is not uncommon. The objective of this research was to evaluate the effects of time of harvest on soybean seed quality (seed composition, germination, seed coat boron, and lignin) in high germinability (HG) breeding lines (50% exotic) developed under high heat. The hypothesis was that seeds of HG lines possess physiological and genetic traits for a better seed quality at harvest maturity and delayed harvest. A 2-year field experiment was conducted under irrigated conditions. Results showed that, at harvest maturity, the exotic HG lines had higher seed protein, oleic acid, sugars, seed coat boron, and seed coat lignin, but lower seed oil compared with the non-exotic checks (Control), confirming our hypothesis. At 28 days after harvest maturity (delayed harvest), the content of seed protein, oleic acid, sugars, seed coat boron, and seed coat lignin were higher in some of the HG lines compared with the checks, indicating a possible involvement of these seed constituents, especially seed coat boron and seed coat lignin, in maintaining seed coat integrity and protecting seed coat against physical damage. Highly significant positive correlations were found between germination and seed protein, oleic acid, sugars, and seed coat boron and seed coat lignin. Highly significant negative correlation was found between germination and oil, linoleic acid, seed coat wrinkling, shattering, and hard seed. Yields of some HG lines were competitive with checks. This research demonstrated that time of harvesting is an important factor influencing seed protein and oil production. Also, since high oleic acid is desirable for oxidative stability, shelf-life and biodiesel properties, using HG lines could positively influence these important traits. This result should suggest to breeders of some of the advantages of selecting for high seed coat boron and

  1. Performance enhancement of the single-phase series active filter by employing the load voltage waveform reconstruction and line current sampling delay reduction methods

    DEFF Research Database (Denmark)

    Senturk, O.S.; Hava, A.M.

    2011-01-01

    This paper proposes the waveform reconstruction method (WRM), which is utilized in the single-phase series active filter's (SAF's) control algorithm, in order to extract the load harmonic voltage component of voltage harmonic type single-phase diode rectifier loads. Employing WRM and the line...... current sampling delay reduction method, a single-phase SAF compensated system provides higher harmonic isolation performance and higher stability margins compared to the system using conventional synchronous-reference-frame-based methods. The analytical, simulation, and experimental studies of a 2.5 k...

  2. Analysing the Zenith Tropospheric Delay Estimates in On-line Precise Point Positioning (PPP) Services and PPP Software Packages.

    Science.gov (United States)

    Mendez Astudillo, Jorge; Lau, Lawrence; Tang, Yu-Ting; Moore, Terry

    2018-02-14

    As Global Navigation Satellite System (GNSS) signals travel through the troposphere, a tropospheric delay occurs due to a change in the refractive index of the medium. The Precise Point Positioning (PPP) technique can achieve centimeter/millimeter positioning accuracy with only one GNSS receiver. The Zenith Tropospheric Delay (ZTD) is estimated alongside with the position unknowns in PPP. Estimated ZTD can be very useful for meteorological applications, an example is the estimation of water vapor content in the atmosphere from the estimated ZTD. PPP is implemented with different algorithms and models in online services and software packages. In this study, a performance assessment with analysis of ZTD estimates from three PPP online services and three software packages is presented. The main contribution of this paper is to show the accuracy of ZTD estimation achievable in PPP. The analysis also provides the GNSS users and researchers the insight of the processing algorithm dependence and impact on PPP ZTD estimation. Observation data of eight whole days from a total of nine International GNSS Service (IGS) tracking stations spread in the northern hemisphere, the equatorial region and the southern hemisphere is used in this analysis. The PPP ZTD estimates are compared with the ZTD obtained from the IGS tropospheric product of the same days. The estimates of two of the three online PPP services show good agreement (<1 cm) with the IGS ZTD values at the northern and southern hemisphere stations. The results also show that the online PPP services perform better than the selected PPP software packages at all stations.

  3. Analysing the Zenith Tropospheric Delay Estimates in On-line Precise Point Positioning (PPP Services and PPP Software Packages

    Directory of Open Access Journals (Sweden)

    Jorge Mendez Astudillo

    2018-02-01

    Full Text Available As Global Navigation Satellite System (GNSS signals travel through the troposphere, a tropospheric delay occurs due to a change in the refractive index of the medium. The Precise Point Positioning (PPP technique can achieve centimeter/millimeter positioning accuracy with only one GNSS receiver. The Zenith Tropospheric Delay (ZTD is estimated alongside with the position unknowns in PPP. Estimated ZTD can be very useful for meteorological applications, an example is the estimation of water vapor content in the atmosphere from the estimated ZTD. PPP is implemented with different algorithms and models in online services and software packages. In this study, a performance assessment with analysis of ZTD estimates from three PPP online services and three software packages is presented. The main contribution of this paper is to show the accuracy of ZTD estimation achievable in PPP. The analysis also provides the GNSS users and researchers the insight of the processing algorithm dependence and impact on PPP ZTD estimation. Observation data of eight whole days from a total of nine International GNSS Service (IGS tracking stations spread in the northern hemisphere, the equatorial region and the southern hemisphere is used in this analysis. The PPP ZTD estimates are compared with the ZTD obtained from the IGS tropospheric product of the same days. The estimates of two of the three online PPP services show good agreement (<1 cm with the IGS ZTD values at the northern and southern hemisphere stations. The results also show that the online PPP services perform better than the selected PPP software packages at all stations.

  4. LINES

    Directory of Open Access Journals (Sweden)

    Minas Bakalchev

    2015-10-01

    Full Text Available The perception of elements in a system often creates their interdependence, interconditionality, and suppression. The lines from a basic geometrical element have become the model of a reductive world based on isolation according to certain criteria such as function, structure, and social organization. Their traces are experienced in the contemporary world as fragments or ruins of a system of domination of an assumed hierarchical unity. How can one release oneself from such dependence or determinism? How can the lines become less “systematic” and forms more autonomous, and less reductive? How is a form released from modernistic determinism on the new controversial ground? How can these elements or forms of representation become forms of action in the present complex world? In this paper, the meaning of lines through the ideas of Le Corbusier, Leonidov, Picasso, and Hitchcock is presented. Spatial research was made through a series of examples arising from the projects of the architectural studio “Residential Transformations”, which was a backbone for mapping the possibilities ranging from playfulness to exactness, as tactics of transformation in the different contexts of the contemporary world.

  5. Vitamin E analogue, D-alpha tocopherol succinate, enhances x-ray induced growth delay of human adenocarcinoma cancer cell line

    International Nuclear Information System (INIS)

    Jaworska, A.; Ottesen, T.E.

    2003-01-01

    The purpose of this study was to assess the effects of d-alpha Tocopherol succinate (alpha-TS) in modifying radiation-induced viability reduction and apoptosis occurrence in the model for normal and cancer cells. Our hypothesis was that alpha-TS enhances the growth-inhibitory effect of x-irradiation in cancer cells and that the effect is more pronounced in these cells than in normal cells. Murine NIH 3T3 Swiss albino embryonic cells and HT29 human Caucasian colon adenocarcinoma cells were used in the experiments. Alpha-TS was added to the cultures 1 h prior to irradiation with doses of 2 or 5Gy of x-ray. After irradiation cells were incubated for 73 h. Trypan blue exclusion viability test and estimation of apoptosis and necrosis were made. Apoptotic and necrotic cells were counted in fluorescence microscope using fluorescence dyes: propidium iodide and Hoechst 33342. For experiments with the dose of 5 Gy at least five series of experiments were performed. At lower doses (up to approximately 25μM/ml) treatment with alpha-TS alone enhanced growth of both cell lines. At higher doses treatment with alpha-TS alone delayed the growth of the cell cultures, accompanied by 20-25% necrosis. At the concentrations higher than 25μM/mL alpha-TS alone caused growth delay of both cell cultures, being much more pronounced for the cancer cell line HT29. At the concentrations of 50 μM/mL, responsible for about 30-60% of growth delay, there was observed a synergy effect for x-rays and alpha-TS for both cell lines. The effect was more pronounced for HT29 cells (DMF=0.48 for HT29 versus DMF=0.73 for NIH 3T3). These results may confirm the views of the literature reports suggesting that use of vitamin E together with radiation could be favorable for colon cancer treatment; however, more experiments using more advanced techniques are needed

  6. A Minor Modification of Leading Edge Discriminator Circuitry with a Delay Line for Baseline Restoration of Scintillation Detectors

    International Nuclear Information System (INIS)

    Izumi, N

    2003-01-01

    Multi-channel neutron time-of-flight detector arrays LaNSA, T-ion, Medusa, and Mandala, have been used for neutron spectroscopy in inertial confinement fusion experiments. These multi-channel neutron detector arrays consist of many identical scintillation detectors (842 ∼ 1024 channel), data acquisition electronics (discriminators, time-to digital converters, and controller). Each detector element is operated in neutron counting mode. Time-of-flight of individual detected neutrons are recorded by time to digital converters. The energy of each detected neutrons is determined from its time-of-flight. The accurate time measurement (Δt ∼ 0.5 ns) and straightforward statistical features of the data obtained with these systems provides good integrity and reliability. The elements detector used in these systems are organic scintillators coupled with photo multiplier tubes. A scintillation detector operated in particle-counting mode requires finite recovery time after each detection event. The recovery time is determined by the time responses of scintillators, photo multiplier tubes, and the dead times of following discriminators and time-to digital converters. The harsh gamma ray background environment of fast ignitor experiments requires detectors that have fast recovery times. In high intensity laser experiments (I > 10 19 W/cm 2 ), strong gamma ray bursts are produced by relativistic laser plasma interactions. Prior to the neutron signal, these strong gamma ray bursts hit the detectors and interfere with the detection of following neutron signals. In these situations, the recovery time of the system after preceding gamma ray bursts is determined mainly by the base line shift of the PMT signal (due to slower decay components of scintillators ''after glow''). Discriminators cannot detect following signal pulses until the proceeding burst decays below its threshold voltage. The base line shift caused by the after glow prolongs the recovery time of the discriminators

  7. Differential expression of conserved germ line markers and delayed segregation of male and female primordial germ cells in a hermaphrodite, the leech helobdella.

    Science.gov (United States)

    Cho, Sung-Jin; Vallès, Yvonne; Weisblat, David A

    2014-02-01

    In sexually reproducing animals, primordial germ cells (PGCs) are often set aside early in embryogenesis, a strategy that minimizes the risk of genomic damage associated with replication and mitosis during the cell cycle. Here, we have used germ line markers (piwi, vasa, and nanos) and microinjected cell lineage tracers to show that PGC specification in the leech genus Helobdella follows a different scenario: in this hermaphrodite, the male and female PGCs segregate from somatic lineages only after more than 20 rounds of zygotic mitosis; the male and female PGCs share the same (mesodermal) cell lineage for 19 rounds of zygotic mitosis. Moreover, while all three markers are expressed in both male and female reproductive tissues of the adult, they are expressed differentially between the male and female PGCs of the developing embryo: piwi and vasa are expressed preferentially in female PGCs at a time when nanos is expressed preferentially in male PGCs. A priori, the delayed segregation of male and female PGCs from somatic tissues and from one another increases the probability of mutations affecting both male and female PGCs of a given individual. We speculate that this suite of features, combined with a capacity for self-fertilization, may contribute to the dramatically rearranged genome of Helobdella robusta relative to other animals.

  8. Comparison of multi-pole shaping and delay line clipping pre-amplifiers for position sensitive NaI(Tl) detectors

    International Nuclear Information System (INIS)

    Freifelder, R.; Karp, J.S.; Wear, J.A.; Lockyer, N.S.; Newcomer, F.M.; Surti, S.; Berg, R. van

    1998-01-01

    NaI(Tl) position sensitive detectors have been used in medical imaging for many years. For PET applications without collimators, the high counting rates place severe demands on such large area detectors. The NaI(Tl) detectors in the PENN-PET scanners are read-out via photomultiplier tubes and preamplifiers. Those preamplifiers use a delay-line clipping technique to shorten the characteristic 240 ns fall time of the NaI(Tl) signal. As an alternative, the authors have investigated a pole-zero network to shorten the signal followed by a multi-pole shaper to produce a symmetric signal suitable for high counting rates. This has been compared to the current design by measuring the energy and spatial resolution of a single detector as a function of different preamplifier designs. Data were taken over a range of ADC integration times and countrates. The new design shows improved energy resolution with short integration times. Effects on spatial resolution and deadtime are reported for large position sensitive detectors at different countrates

  9. Optical buffer based on monolithic InP phased-array 1×16 switch with silica-PLC pitch converter and ultra-compact coiled fiber delay lines

    NARCIS (Netherlands)

    Tanemura, T.; Soganci, I. M.; Oyama, T.; Ohyama, T.; Mino, S.; Williams, K. A.; Calabretta, N.; Dorren, H. J S; Nakano, Y.

    2010-01-01

    We demonstrate large-capacity high-resolution optical buffer, comprising 1×16 InP switch and ultra-compact delay lines based on thin-cladding highly nonlinear fibers. Silica-PLC-based pitch converter is employed to realize uniform coupling from all 16 switch ports simultaneously.

  10. Improvements to the on-line mass separator, RAMA, and the beta-delayed charged-particle emission of proton-rich sd shell nuclei

    International Nuclear Information System (INIS)

    Ognibene, T.J.

    1996-03-01

    To overcome the extreme difficulties encountered in the experimental decay studies of proton drip line nuclei, several techniques have been utilized, including a helium-jet transport system, particle identification detectors and mass separation. Improvements to the ion source/extraction region of the He-jet coupled on-line Recoil Atom Mass Analyzer (RAMA) and its target/ion source coupling resulted in significant increases in RAMA efficiencies and its mass resolution, as well as reductions in the overall transit time. At the 88-Inch Cyclotron at LBNL, the decays of 31 Cl, 27 P and 28 P, with half-lives of 150 msec, 260 msec and 270.3 msec, respectively, were examined using a he-jet and low-energy gas ΔE-gas ΔE-silicon E detector telescopes. Total beta-delayed proton branches of 0.3% and 0.07% in 31 Cl and 27 P, respectively, were estimated. Several proton peaks that had been previously assigned to the decay of 31 Cl were shown to be from the decay of 25 Si. In 27 P, two proton groups at 459 ± 14 keV and 610 ± 11 keV, with intensities of 7 ± 3% and 92 ± 4% relative to the main (100%) group were discovered. The Gamow-Teller component of the preceding beta-decay of each observed proton transition was compared to results from shell model calculations. Finally, a new proton transition was identified, following the β-decay of 28 P, at 1,444 ± 12 keV with a 1.7 ± 0.5% relative intensity to the 100% group. Using similar low-energy detector telescopes and the mass separator TISOL at TRIUMF, the 109 msec and 173 msec activities, 17 Ne and 33 Ar, were studied. A new proton group with energy 729 ± 15 keV was observed following the beta-decay of 17 Ne. Several discrepancies between earlier works as to the energies, intensities and assignments of several proton transitions from 17 Ne and 33 Ar were resolved

  11. Delayed fission

    Energy Technology Data Exchange (ETDEWEB)

    Hatsukawa, Yuichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-07-01

    Delayed fission is a nuclear decay process that couples {beta} decay and fission. In the delayed fission process, a parent nucleus undergoes {beta} decay and thereby populates excited states in the daughter. If these states are of energies comparable to or greater than the fission barrier of the daughter, then fission may compete with other decay modes of the excited states in the daughter. In this paper, mechanism and some experiments of the delayed fission will be discussed. (author)

  12. Delayed initiation of radiotherapy for glioblastoma: how important is it to push to the front (or the back) of the line?

    Science.gov (United States)

    Lawrence, Yaacov Richard; Blumenthal, Deborah T; Matceyevsky, Diana; Kanner, Andrew A; Bokstein, Felix; Corn, Benjamin W

    2011-10-01

    Glioblastoma is a malignant tumor characterized by a rapid proliferation rate. Contemporary multi-modality treatment consists of maximal surgical resection followed by radiation therapy (RT) combined with cytotoxic chemotherapy. The optimal timing of these different steps is not known. Four studies from the pre-temozolomide era, encompassing a total of 4,584 subjects, have examined the consequences of a delay between resection and starting RT. Whereas the two small single-institution studies found this delay to be detrimental, two large multi-institutional studies found delay to be either slightly beneficial or at least not harmful. Here, we critically compare the methodologies and results presented in these studies, and include a novel analysis of the combined datasets. We conclude that moderate wait periods (up to 4-6 weeks post-operatively) are safe and may be modestly beneficial. Conversely, there is no evidence to justify waiting longer than 6 weeks. Underlying radiobiological principles are discussed.

  13. How does variability in input load relate to the probability of critically delayed delivery in a simple Multipart Re-entrant Flow-line problem?

    DEFF Research Database (Denmark)

    Nielsen, Erland Hejn

    2003-01-01

    of the estimation of the probability of critically delayed delivery beyond a specified threshold value given a certain production batch size and try to establish a relation to certain parameters that can be linked to the degree of regularity of the arrival stream of parts to the job/flow-shop. This last aspect...... relates remotely to the Lean Thinking philosophy that praises the smooth and uninterrupted production flow to be beneficial to the overall operation of productive plants in general, and we will link our findings to this discussion as well....

  14. Delayed Ejaculation

    Science.gov (United States)

    ... cases, it is due to a combination of physical and psychological concerns. Psychological causes of delayed ejaculation include: Depression, anxiety or other mental health conditions Relationship problems due to stress, poor communication ...

  15. Delayed growth

    Science.gov (United States)

    ... Slow rate of growth; Retarded growth and development; Growth delay Images Toddler development References Cooke DW, Divall SA, Radovick S. Normal and aberrant growth in children. In: Melmed S, Polonsky KS, Larsen PR, ...

  16. An Empirical Evaluation of Language-Tailored PDLs.

    Science.gov (United States)

    1982-05-01

    principles in experimental design. New York: McGraw- Hill, 1971. -21- APPENDIX A PDL FORMATS I iiCLDL4. pA; Bl.ANK(-NO1 T nui.s.i VMC~ PROGRAM...O2O70 IF XJ) LE , X(J+I)) -;0 T 230 -43- TECHNICAL REPORTS DISTRIBUTION LIST -45- OFFICE OF NAVAL RESEARCH Code 442 TECHNICAL REPORTS DISTRIBUTION LIST...OSD Department of the Navy Capt. Paul R. Chatelier Office of the Deputy Under Secretary ONR Eastern/Central Regional Officeof DefenseOREatr/etaReinl

  17. Developmental delay

    Science.gov (United States)

    Nutrition support is essential for the care of the child with developmental delay. After a thorough evaluation, an individualized intervention plan that accounts for the child’s nutrition status, feeding ability, and medical condition may be determined. Nutrition assessments may be performed at leas...

  18. Delayed Puberty

    DEFF Research Database (Denmark)

    Kolby, Nanna; Busch, Alexander Siegfried; Juul, Anders

    2017-01-01

    . The underlying reasons for the large variation in the age at pubertal onset are not fully established; however, nutritional status and socioeconomic and environmental factors are known to be influencing, and a significant amount of influencing genetic factors have also been identified. The challenges...... optimal in discriminating especially CDGP from HH. Management of the delayed puberty depends on the etiology. For boys with CDGP an observational period will often reveal imminent puberty. If puberty is not progressing spontaneously, sex steroid replacement is effective in stimulating the development...

  19. Delayed puberty in girls

    Science.gov (United States)

    ... sexual development - girls; Pubertal delay - girls; Constitutional delayed puberty ... In most cases of delayed puberty, growth changes just begin later than usual, sometimes called a late bloomer. Once puberty begins, it progresses normally. This pattern runs ...

  20. Delayed Puberty (For Teens)

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Delayed Puberty KidsHealth / For Teens / Delayed Puberty What's in this ... wonder if there's anything wrong. What Is Delayed Puberty? Puberty is the time when your body grows ...

  1. Speech and Language Delay

    Science.gov (United States)

    ... OTC Relief for Diarrhea Home Diseases and Conditions Speech and Language Delay Condition Speech and Language Delay Share Print Table of Contents1. ... Treatment6. Everyday Life7. Questions8. Resources What is a speech and language delay? A speech and language delay ...

  2. Delay 25 an ASIC for timing adjustment in LHC

    NARCIS (Netherlands)

    Furtado, H.; Schrader, J.H.R.; Marchioro, A.; Moreira, P.

    A five channel programmable delay line ASIC was designed featuring 4 channels that allow to phase delay periodic or non-periodic digital signals and a master channel that can be used to phase delay a clock signal. The master channel serves as a calibration reference guaranteeing independence from

  3. UAVs and Control Delays

    National Research Council Canada - National Science Library

    de Vries, S. C

    2005-01-01

    .... Delays of about 250-300 ms often lead to unacceptable airplane handling qualities. Techniques such as filtering and predictive displays may extend the range of acceptable delays up to about 400 ms...

  4. Delayed puberty in boys

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/007695.htm Delayed puberty in boys To use the sharing features on this page, please enable JavaScript. Delayed puberty in boys is when puberty does not begin ...

  5. Delayed Orgasm and Anorgasmia

    OpenAIRE

    Jenkins, Lawrence C.; Mulhall, John P.

    2015-01-01

    Delayed orgasm/anorgasmia defined as the persistent or recurrent difficulty, delay in, or absence of attaining orgasm after sufficient sexual stimulation, which causes personal distress. Delayed orgasm and anorgasmia are associated with significant sexual dissatisfaction. A focused medical history can shed light on the potential etiologies; which include: medications, penile sensation loss, endocrinopathies, penile hyperstimulation and psychological etiologies, amongst others. Unfortunately, ...

  6. Delay generation methods with reduced memory requirements

    DEFF Research Database (Denmark)

    Tomov, Borislav Gueorguiev; Jensen, Jørgen Arendt

    2003-01-01

    Modern diagnostic ultrasound beamformers require delay information for each sample along the image lines. In order to avoid storing large amounts of focusing data, delay generation techniques have to be used. In connection with developing a compact beamformer architecture, recursive algorithms were......) For the best parametric approach, the gate count was 2095, the maximum operation speed was 131.9 MHz, the power consumption at 40 MHz was 10.6 mW, and it requires 4 12-bit words for each image line and channel. 2) For the piecewise-linear approximation, the corresponding numbers are 1125 gates, 184.9 MHz, 7...

  7. Delayed orgasm and anorgasmia.

    Science.gov (United States)

    Jenkins, Lawrence C; Mulhall, John P

    2015-11-01

    Delayed orgasm/anorgasmia defined as the persistent or recurrent difficulty, delay in, or absence of attaining orgasm after sufficient sexual stimulation, which causes personal distress. Delayed orgasm and anorgasmia are associated with significant sexual dissatisfaction. A focused medical history can shed light on the potential etiologies, which include medications, penile sensation loss, endocrinopathies, penile hyperstimulation, and psychological etiologies. Unfortunately, there are no excellent pharmacotherapies for delayed orgasm/anorgasmia, and treatment revolves largely around addressing potential causative factors and psychotherapy. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  8. American Dream Delayed

    DEFF Research Database (Denmark)

    Khorunzhina, Natalia; Miller, Robert A.

    This paper investigates the delay in homeownership and a subsequent reduction in homeownership rate observed over the past decades. We focus on the delay in giving birth to children and increased labor market participation as contributing factors to homeownership dynamics for prime-age female hou...

  9. RNAi silenced Dd-grp94 (Dictyostelium discoideum glucose-regulated protein 94 kDa) cell lines in Dictyostelium exhibit marked reduction in growth rate and delay in development.

    Science.gov (United States)

    Baviskar, Sandhya N; Shields, Malcolm S

    2010-01-01

    Glucose-regulated 94 kDa protein (Grp94) is a resident of the endoplasmic reticulum (ER) of multicellular eukaryotes. It is a constitutively expressed protein that is overexpressed in certain abnormal conditions of the cell such as depletion of glucose and calcium, and low oxygen and pH. The protein is also implicated in diseased conditions like cancer and Alzheimer's disease. In this study, the consequences of downregulation of Grp94 were investigated at both unicellular and multicellular stages of Dictyostelium discoideum. Previous studies have shown the expression of Dd-Grp94 (Dictyostelium discoideum glucose-regulated 94 kDa protein) in wild-type cells varies during development, and overexpression of Dd-Grp94 leads to abnormal cell shape and inhibition of development (i.e., formation of fruiting bodies). Grp94 is a known calcium binding protein and an efficient calcium buffer. Therefore, in the present study we hypothesized that downregulation of Dd-Grp94 protein would affect Dictyostelium cell structure, growth, and development. We found that Dd-grp94 RNAi recombinants exhibited reduced growth rate, cell size, and a subtle change in cell motility compared to the parental cells. The recombinants also exhibited a delay in development and small fruiting bodies. These results establish that Dd-grp94 plays a crucial role in determining normal cell structure, growth and differentiation.

  10. Delayed power analysis

    International Nuclear Information System (INIS)

    Adamovich, L.A.; Azarov, V.V.

    1999-01-01

    Time dependent core power behavior in a nuclear reactor is described with well-known neutron kinetics equations. At the same time, two portions are distinguished in energy released from uranium nuclei fission; one released directly at fission and another delayed (residual) portion produced during radioactive decay of fission products. While prompt power is definitely described with kinetics equations, the delayed power presentation still remains outstanding. Since in operation the delayed power part is relatively small (about 6%) operation, it can be neglected for small reactivity disturbances assuming that entire power obeys neutron kinetics equations. In case of a high negative reactivity rapidly inserted in core (e.g. reactor scram initiation) the prompt and delayed components can be calculated separately with practically no impact on each other, employing kinetics equations for prompt power and known approximation formulas for delayed portion, named residual in this specific case. Under substantial disturbances the prompt component in the dynamic process becomes commensurable with delayed portion, thus making necessary to take into account their cross impact. A system of differential equations to describe time-dependent behavior of delayed power is presented. Specific NPP analysis shows a way to significantly simplify the task formulation. (author)

  11. Neutron delayed choice experiments

    International Nuclear Information System (INIS)

    Bernstein, H.J.

    1986-01-01

    Delayed choice experiments for neutrons can help extend the interpretation of quantum mechanical phenomena. They may also rule out alternative explanations which static interference experiments allow. A simple example of a feasible neutron test is presented and discussed. (orig.)

  12. Quad nanosecond delay module

    International Nuclear Information System (INIS)

    McDonald, R.J.; Hunter, J.B.; Wozniak, G.J.

    1986-04-01

    Four nanosecond (ns) delay units have been designed to fit in a single-width NIM module. This module is particularly suited for use in conjunction with quad constant fraction timing discriminators (CFTDs) since it has four delay units that can be placed adjacent to the four units of the CFTD. A series of different length cables connected via DIP toggle switches provide delays of 0.60 ns in 4 ns increments. Thus, the CFTD delay can be optimized for pulses of different rise times from approx.10-100 ns. Design work for the PC board and silkscreening of the front panel were done with the MacDraw program on the Apple Mackintosh computer and printed with the Lasewriter printer. 6 refs

  13. Delayed rule following

    OpenAIRE

    Schmitt, David R.

    2001-01-01

    Although the elements of a fully stated rule (discriminative stimulus [SD], some behavior, and a consequence) can occur nearly contemporaneously with the statement of the rule, there is often a delay between the rule statement and the SD. The effects of this delay on rule following have not been studied in behavior analysis, but they have been investigated in rule-like settings in the areas of prospective memory (remembering to do something in the future) and goal pursuit. Discriminative even...

  14. Vernier Delay Unit

    International Nuclear Information System (INIS)

    Pierce, W.B.

    1984-10-01

    This module will accept differential ECL pulses from the auxiliary rear panel or NIM level pulses from the front panel. The pulses are produced at the output with a fixed delay that is software programmable in steps of 0.1 ns over the range of 0.1 to 10.5 ns. Multiple outputs are available at the front panel. Minimum delay through the module is 9 ns

  15. Quad precision delay generator

    International Nuclear Information System (INIS)

    Krishnan, Shanti; Gopalakrishnan, K.R.; Marballi, K.R.

    1997-01-01

    A Quad Precision Delay Generator delays a digital edge by a programmed amount of time, varying from nanoseconds to microseconds. The output of this generator has an amplitude of the order of tens of volts and rise time of the order of nanoseconds. This was specifically designed and developed to meet the stringent requirements of the plasma focus experiments. Plasma focus is a laboratory device for producing and studying nuclear fusion reactions in hot deuterium plasma. 3 figs

  16. Nuclear size and cell division delay

    International Nuclear Information System (INIS)

    Bird, R.P.

    1986-01-01

    Radiation-induced division delay has been linked to damage at the nuclear envelope. Further, cells in G 2 phase are drastically arrested by high LET radiation such that single particles traversing cell nuclei may produce measurable division delay. A modest effort was initiated using two related cell lines of different size, near-diploid cells and near-tetraploid cells of Chinese hamster origin, to compare their sensitivity for radiation-induced division delay. If the nuclear surface is the critical target, then a larger nuclear cross-section presented to an alpha-particle beam should exhibit delay induced by a lesser particle fluence. Preliminary estimates of the extent of delay in asynchronous cultures following low doses of gamma-irradiation or of alpha-irradiation were made by in-situ observation of the time of onset of mitosis and by fixation and staining of cultures to determine the mitotic index as a function of time after irradiation. The basic approach to evaluating division delay will be to use Colecemid to accumulate mitotic cells over a period of time

  17. Modelling delays in pharmacokinetics

    International Nuclear Information System (INIS)

    Farooqi, Z.H.; Lambrecht, R.M.

    1990-01-01

    Linear system analysis has come to form the backbone of pharmacokinetics. Natural systems usually involve time delays, thus models incorporating them would be an order closer approximation to the real world compared to those that do not. Delays may be modelled in several ways. The approach considered in this study is to have a discrete-time delay dependent rate with the delay respresenting the duration between the entry of a drug into a compartment and its release in some form (may be as a metabolite) from the compartment. Such a delay may be because of one or more of several physiological reasons, like, formation of a reservoir, slow metabolism, or receptor binding. The mathematical structure this gives rise to is a system of delay-differential equations. Examples are given of simple one and two compartment systems with drugs like bumetanide, carbamazepine, and quinolone-caffeine interaction. In these examples generally a good fit is obtained and the suggested models form a good approximation. 21 refs., 6 figs

  18. Delay-Range-Dependent H∞ Control for Automatic Mooring Positioning System with Time-Varying Input Delay

    Directory of Open Access Journals (Sweden)

    Xiaoyu Su

    2014-01-01

    Full Text Available Aiming at the economy and security of the positioning system in semi-submersible platform, the paper presents a new scheme based on the mooring line switching strategy. Considering the input delay in switching process, H∞ control with time-varying input delay is designed to calculate the control forces to resist disturbing forces. In order to reduce the conservativeness, the information of the lower bound of delay is taken into account, and a Lyapunov function which contains the range of delay is constructed. Besides, the input constraint is considered to avoid breakage of mooring lines. The sufficient conditions for delay-range-dependent stabilization are derived in terms of LMI, and the controller is also obtained. The effectiveness of the proposed approach is illustrated by a realistic design example.

  19. Optimal Joint Expected Delay Forwarding in Delay Tolerant Networks

    OpenAIRE

    Jia Xu; Xin Feng; Wen Jun Yang; Ru Chuan Wang; Bing Qing Han

    2013-01-01

    Multicopy forwarding schemes have been employed in delay tolerant network (DTN) to improve the delivery delay and delivery rate. Much effort has been focused on reducing the routing cost while retaining high performance. This paper aims to provide an optimal joint expected delay forwarding (OJEDF) protocol which minimizes the expected delay while satisfying a certain constant on the number of forwardings per message. We propose a comprehensive forwarding metric called joint expected delay (JE...

  20. A Quantized Analog Delay for an ir-UWB Quadrature Downconversion Autocorrelation Receiver

    NARCIS (Netherlands)

    Bagga, S.; Zhang, L.; Serdijn, W.A.; Long, J.R.; Busking, E.B.

    2005-01-01

    A quantized analog delay is designed as a requirement for the autocorrelation function in the quadrature downconversion autocorrelation receiver (QDAR). The quantized analog delay is comprised of a quantizer, multiple binary delay lines and an adder circuit. Being the foremost element, the quantizer

  1. Radiosensitivity of mesothelioma cell lines

    International Nuclear Information System (INIS)

    Haekkinen, A.M.; Laasonen, A.; Linnainmaa, K.; Mattson, K.; Pyrhoenen, S.

    1996-01-01

    The present study was carried out in order to examine the radiosensitivity of malignant pleural mesothelioma cell lines. Cell kinetics, radiation-induced delay of the cell cycle and DNA ploidy of the cell lines were also determined. For comparison an HeLa and a human foetal fibroblast cell line were simultaneously explored. Six previously cytogenetically and histologically characterized mesothelioma tumor cell lines were applied. A rapid tiazolyl blue microtiter (MTT) assay was used to analyze radiosensitivity and cell kinetics and DNA ploidy of the cultured cells were determined by flow cytometry. The survival fraction after a dose of 2 Gy (SF2), parameters α and β of the linear quadratic model (LQ-model) and mean inactivation dose (D MID ) were also estimated. The DNA index of four cell lines equaled 1.0 and two cell lines equaled 1.5 and 1.6. Different mesothelioma cell lines showed a great variation in radiosensitivity. Mean survival fraction after a radiation dose of 2 Gy (SF2) was 0.60 and ranged from 0.36 to 0.81 and mean α value was 0.26 (range 0.48-0.083). The SF2 of the most sensitive diploid mesothelioma cell line was 0.36: Less than that of the foetal fibroblast cell line (0.49). The survival fractions (0.81 and 0.74) of the two most resistant cell lines, which also were aneuploid, were equal to that of the HeLa cell line (0.78). The α/β ratios of the most sensitive cell lines were almost an order of magnitude greater than those of the two most resistant cell lines. Radiation-induced delay of the most resistant aneuploid cell line was similar to that of HeLa cells but in the most sensitive (diploid cells) there was practically no entry into the G1 phase following the 2 Gy radiation dose during 36 h. (orig.)

  2. Assessing delay discounting in mice

    OpenAIRE

    Mitchell, Suzanne H.

    2014-01-01

    Delay discounting (also intertemporal choice or impulsive choice) is the process by which delayed outcomes, such as delayed food delivery, are valued less than the same outcomes delivered immediately or with a shorter delay. This process is of interest because many psychopathologies, including substance dependence, pathological gambling, attention deficit hyperactivity disorder and conduct disorder, are characterized by heightened levels of delay discounting. Some of these disorders are herit...

  3. Estimating Delays In ASIC's

    Science.gov (United States)

    Burke, Gary; Nesheiwat, Jeffrey; Su, Ling

    1994-01-01

    Verification is important aspect of process of designing application-specific integrated circuit (ASIC). Design must not only be functionally accurate, but must also maintain correct timing. IFA, Intelligent Front Annotation program, assists in verifying timing of ASIC early in design process. This program speeds design-and-verification cycle by estimating delays before layouts completed. Written in C language.

  4. Permissible Delay in Payments

    Directory of Open Access Journals (Sweden)

    Yung-Fu Huang

    2007-01-01

    Full Text Available The main purpose of this paper wants to investigate the optimal retailer's lot-sizing policy with two warehouses under partially permissible delay in payments within the economic order quantity (EOQ framework. In this paper, we want to extend that fully permissible delay in payments to the supplier would offer the retailer partially permissible delay in payments. That is, the retailer must make a partial payment to the supplier when the order is received. Then the retailer must pay off the remaining balance at the end of the permissible delay period. In addition, we want to add the assumption that the retailer's storage space is limited. That is, the retailer will rent the warehouse to store these exceeding items when the order quantity is larger than retailer's storage space. Under these conditions, we model the retailer's inventory system as a cost minimization problem to determine the retailer's optimal cycle time and optimal order quantity. Three theorems are developed to efficiently determine the optimal replenishment policy for the retailer. Finally, numerical examples are given to illustrate these theorems and obtained a lot of managerial insights.

  5. Delayed neutrons in ANSTO

    International Nuclear Information System (INIS)

    Wall, T.

    1988-01-01

    Delayed neutron analysis carried out at the Australian Nuclear Scientific and Technology Organization facilities, provides a fast, high sensitivity, low cost, reliable method, particularly suitable for large batches of samples, and for non destructive analysis of a range of materials. While its main use has been in uranium exploration, other applications include archeological investigations, agriculture, oceanography and biology

  6. Signal integrity analysis on discontinuous microstrip line

    International Nuclear Information System (INIS)

    Qiao, Qingyang; Dai, Yawen; Chen, Zipeng

    2013-01-01

    In high speed PCB design, microstirp lines were used to control the impedance, however, the discontinuous microstrip line can cause signal integrity problems. In this paper, we use the transmission line theory to study the characteristics of microstrip lines. Research results indicate that the discontinuity such as truncation, gap and size change result in the problems such as radiation, reflection, delay and ground bounce. We change the discontinuities to distributed parameter circuits, analysed the steady-state response and transient response and the phase delay. The transient response cause radiation and voltage jump.

  7. Delayed traumatic intracranial hematoma

    International Nuclear Information System (INIS)

    Tomita, Hiroki

    1984-01-01

    CT was performed serially within 24 hours after head injury in 64 patients having Glasgow Coma Scale of 14 or less or cranial fracture shown on roentgenogram. Delayed traumatic extradural hematoma was observed within 7-12 hours after head injury in 6 cases (9.4%). This was prominent in the frontal and occipital regions (67%). Good recovery was seen in 83.3%. Delayed traumatic intracerebral hematoma was observed within 6-24 hours after head injury in 17 cases (26.6%). This higher incidence was related to contre coup injury. Conservative treatment was possible in 14 of the 17 patients (82.4%), showing good recovery in 70%. (Namekawa, K.)

  8. Time-Delay Interferometry

    Directory of Open Access Journals (Sweden)

    Massimo Tinto

    2014-08-01

    Full Text Available Equal-arm detectors of gravitational radiation allow phase measurements many orders of magnitude below the intrinsic phase stability of the laser injecting light into their arms. This is because the noise in the laser light is common to both arms, experiencing exactly the same delay, and thus cancels when it is differenced at the photo detector. In this situation, much lower level secondary noises then set the overall performance. If, however, the two arms have different lengths (as will necessarily be the case with space-borne interferometers, the laser noise experiences different delays in the two arms and will hence not directly cancel at the detector. In order to solve this problem, a technique involving heterodyne interferometry with unequal arm lengths and independent phase-difference readouts has been proposed. It relies on properly time-shifting and linearly combining independent Doppler measurements, and for this reason it has been called time-delay interferometry (TDI. This article provides an overview of the theory, mathematical foundations, and experimental aspects associated with the implementation of TDI. Although emphasis on the application of TDI to the Laser Interferometer Space Antenna (LISA mission appears throughout this article, TDI can be incorporated into the design of any future space-based mission aiming to search for gravitational waves via interferometric measurements. We have purposely left out all theoretical aspects that data analysts will need to account for when analyzing the TDI data combinations.

  9. Delayed child-bearing.

    Science.gov (United States)

    Johnson, Jo-Ann; Tough, Suzanne

    2012-01-01

    To provide an overview of delayed child-bearing and to describe the implications for women and health care providers. Delayed child-bearing, which has increased greatly in recent decades, is associated with an increased risk of infertility, pregnancy complications, and adverse pregnancy outcome. This guideline provides information that will optimize the counselling and care of Canadian women with respect to their reproductive choices. Maternal age is the most important determinant of fertility, and obstetric and perinatal risks increase with maternal age. Many women are unaware of the success rates or limitations of assisted reproductive technology and of the increased medical risks of delayed child-bearing, including multiple births, preterm delivery, stillbirth, and Caesarean section. This guideline provides a framework to address these issues. Studies published between 2000 and August 2010 were retrieved through searches of PubMed and the Cochrane Library using appropriate key words (delayed child-bearing, deferred pregnancy, maternal age, assisted reproductive technology, infertility, and multiple births) and MeSH terms (maternal age, reproductive behaviour, fertility). The Internet was also searched using similar key words, and national and international medical specialty societies were searched for clinical practice guidelines and position statements. Data were extracted based on the aims, sample, authors, year, and results. The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). The Society of Obstetricians and Gynaecologists of Canada. RECOMMENDATIONS 1. Women who delay child-bearing are at increased risk of infertility. Prospective parents, especially women, should know that their fecundity and fertility begin to decline significantly after 32 years of age. Prospective parents should know that assisted reproductive technologies cannot guarantee a live birth or completely

  10. Delaying information search

    Directory of Open Access Journals (Sweden)

    Yaniv Shani

    2012-11-01

    Full Text Available In three studies, we examined factors that may temporarily attenuate information search. People are generally curious and dislike uncertainty, which typically encourages them to look for relevant information. Despite these strong forces that promote information search, people sometimes deliberately delay obtaining valuable information. We find they may do so when they are concerned that the information might interfere with future pleasurable activities. Interestingly, the decision to search or to postpone searching for information is influenced not only by the value and importance of the information itself but also by well-being maintenance goals related to possible detrimental effects that negative knowledge may have on unrelated future plans.

  11. Acoustic Wave Propagation in Pressure Sense Lines

    Science.gov (United States)

    Vitarius, Patrick; Gregory, Don A.; Wiley, John; Korman, Valentin

    2003-01-01

    Sense lines are used in pressure measurements to passively transmit information from hostile environments to areas where transducers can be used. The transfer function of a sense line can be used to obtain information about the measured environment from the protected sensor. Several properties of this transfer function are examined, including frequency dependence, Helmholtz resonance, and time of flight delay.

  12. Vehicle barrier with access delay

    Science.gov (United States)

    Swahlan, David J; Wilke, Jason

    2013-09-03

    An access delay vehicle barrier for stopping unauthorized entry into secure areas by a vehicle ramming attack includes access delay features for preventing and/or delaying an adversary from defeating or compromising the barrier. A horizontally deployed barrier member can include an exterior steel casing, an interior steel reinforcing member and access delay members disposed within the casing and between the casing and the interior reinforcing member. Access delay members can include wooden structural lumber, concrete and/or polymeric members that in combination with the exterior casing and interior reinforcing member act cooperatively to impair an adversarial attach by thermal, mechanical and/or explosive tools.

  13. Delayed chromosomal instability induced by DNA damage

    International Nuclear Information System (INIS)

    Morgan, W.F.; Marder, B.A.; Day, J.P.

    1994-01-01

    Cellular exposure to DNA damaging agents rapidly results in a dose dependent increase in chromosomal breakage and gross structural chromosomal rearrangements. Over recent years, evidence has been accumulating indicating genomic instability can manifest multiple generations after cellular exposure to physical and chemical DNA damaging agents. Genomic instability manifests in the progeny of surviving cells, and has been implicated in mutation, gene application, cellular transformation, and cell killing. To investigate chromosome instability following DNA damage, we have used fluorescence in situ hybridization to detect chromosomal rearrangements in a human/hamster somatic hybrid cell line following exposure to ionizing radiation. Delayed chromosomal instability was detected when multiple populations of uniquely arranged metaphases were observed in clonal isolates raised from single cells surviving X-irradiation many generations after exposure. At higher radiation doses, chromosomal instability was observed in a relatively high frequency of surviving clones and, in general, those clones showed delayed chromosome instability also showed reduced survival as measured by colony forming ability

  14. Delayed rule following.

    Science.gov (United States)

    Schmitt, D R

    2001-01-01

    Although the elements of a fully stated rule (discriminative stimulus [S(D)], some behavior, and a consequence) can occur nearly contemporaneously with the statement of the rule, there is often a delay between the rule statement and the S(D). The effects of this delay on rule following have not been studied in behavior analysis, but they have been investigated in rule-like settings in the areas of prospective memory (remembering to do something in the future) and goal pursuit. Discriminative events for some behavior can be event based (a specific setting stimulus) or time based. The latter are more demanding with respect to intention following and show age-related deficits. Studies suggest that the specificity with which the components of a rule (termed intention) are stated has a substantial effect on intention following, with more detailed specifications increasing following. Reminders of an intention, too, are most effective when they refer specifically to both the behavior and its occasion. Covert review and written notes are two effective strategies for remembering everyday intentions, but people who use notes appear not to be able to switch quickly to covert review. By focusing on aspects of the setting and rule structure, research on prospective memory and goal pursuit expands the agenda for a more complete explanation of rule effects.

  15. Pseudotumoral delayed cerebral radionecrosis

    International Nuclear Information System (INIS)

    Ciaudo-Lacroix, C.; Lapresle, J.

    1985-01-01

    A 60 year-old woman with a scalp epithelioma underwent radiotherapy, the dose being 57 Gray. A first epileptic seizure occurred twenty months later. Neurological examination revealed signs of left hemisphere involvement. γEG, angiography, CT scans, demonstrated a pseudotumoral avascular process. On account of the localisation, the patient being right-handed, no surgical procedure was performed. In spite of corticotherapy and anticonvulsive treatment, seizures recurred and neurological signs slowly progressed. The patient died, 22 months after the first seizure, of an associated disseminated carcinoma with cachexia. Neuropathological examination showed a massive lesion presenting all the features of delayed radionecrosis in the left hemisphere: situated mainly in the white matter; numerous vascular abnormalities; wide-spread demyelination; disappearance of oligoglial cells. The Authors recall the clinical and anatomical aspects of this condition for which the only successful treatment is surgical removal when location and size of the lesion permit. Finally, the mechanisms which have been proposed to explain this delayed cerebral radionecrosis are discussed [fr

  16. Pseudotumoral delayed cerebral radionecrosis

    Energy Technology Data Exchange (ETDEWEB)

    Ciaudo-Lacroix, C; Lapresle, J [Centre Hospitalier de Bicetre, 94 - Le Kremlin-Bicetre (France)

    1985-01-01

    A 60 year-old woman with a scalp epithelioma underwent radiotherapy, the dose being 57 Gray. A first epileptic seizure occurred twenty months later. Neurological examination revealed signs of left hemisphere involvement. ..gamma..EG, angiography, CT scans, demonstrated a pseudotumoral avascular process. On account of the localisation, the patient being right-handed, no surgical procedure was performed. In spite of corticotherapy and anticonvulsive treatment, seizures recurred and neurological signs slowly progressed. The patient died, 22 months after the first seizure, of an associated disseminated carcinoma with cachexia. Neuropathological examination showed a massive lesion presenting all the features of delayed radionecrosis in the left hemisphere: situated mainly in the white matter; numerous vascular abnormalities; wide-spread demyelination; disappearance of oligoglial cells. The Authors recall the clinical and anatomical aspects of this condition for which the only successful treatment is surgical removal when location and size of the lesion permit. Finally, the mechanisms which have been proposed to explain this delayed cerebral radionecrosis are discussed.

  17. High Line

    DEFF Research Database (Denmark)

    Kiib, Hans

    2015-01-01

    At just over 10 meters above street level, the High Line extends three kilometers through three districts of Southwestern Manhattan in New York. It consists of simple steel construction, and previously served as an elevated rail line connection between Penn Station on 34th Street and the many....... The High Line project has been carried out as part of an open conversion strategy. The result is a remarkable urban architectural project, which works as a catalyst for the urban development of Western Manhattan. The greater project includes the restoration and reuse of many old industrial buildings...

  18. Stability and delay sensitivity of neutral fractional-delay systems.

    Science.gov (United States)

    Xu, Qi; Shi, Min; Wang, Zaihua

    2016-08-01

    This paper generalizes the stability test method via integral estimation for integer-order neutral time-delay systems to neutral fractional-delay systems. The key step in stability test is the calculation of the number of unstable characteristic roots that is described by a definite integral over an interval from zero to a sufficient large upper limit. Algorithms for correctly estimating the upper limits of the integral are given in two concise ways, parameter dependent or independent. A special feature of the proposed method is that it judges the stability of fractional-delay systems simply by using rough integral estimation. Meanwhile, the paper shows that for some neutral fractional-delay systems, the stability is extremely sensitive to the change of time delays. Examples are given for demonstrating the proposed method as well as the delay sensitivity.

  19. Denials and Delays of Radioactive Material Shipments

    International Nuclear Information System (INIS)

    El-Shinawy, R.M.K.

    2011-01-01

    delays of shipments of radioactive materials forms an important issue today. Radioactive materials need to be transported using all modes of transport for use in different applications such as public health, industry, research and production of nuclear power. The transport of radioactive materials is governed by national and international regulations, which are based on the International Atomic Energy Agency (IAEA) regulations for safe transport of radioactive materials (TS-R-1). These regulations ensure high standards of safety. Recently there were increasing numbers of instances of denials and delays of shipments of radioactive materials even when complying with the regulations. The denials and delays can result in difficulties to patients and others who rely on products sterilized by radiation. Therefore there is an urgent need for a universally accepted approach to solve this problem. In response, the IAEA has formed an International Steering Committee (ISC) on denials and delays of radioactive materials. Also, it designate the National Focal Points (NFP) representative to help the ISC members and the IAEA by informing about denial operations and how they can help. The Steering Committee developed and adopted an action plan which includes the action to be taken. This plan is based on: Awareness, Training, Communication, Lobbying for marketing, Economic and Harmonization among member states. It is important to work within the mandate of the ISC and in the line of action plan on denials and delays. It identified the following network members such as: National Focal Points, Regional Coordinators, National Committee, National Representative for different modes of transport and similar bodies, Carriers, Producers and Suppliers, Different civil societies, NGO's, Ministry of transport and others.

  20. Delayed breast implant reconstruction

    DEFF Research Database (Denmark)

    Hvilsom, Gitte B.; Hölmich, Lisbet R.; Steding-Jessen, Marianne

    2012-01-01

    We evaluated the association between radiation therapy and severe capsular contracture or reoperation after 717 delayed breast implant reconstruction procedures (288 1- and 429 2-stage procedures) identified in the prospective database of the Danish Registry for Plastic Surgery of the Breast during...... of radiation therapy was associated with a non-significantly increased risk of reoperation after both 1-stage (HR = 1.4; 95% CI: 0.7-2.5) and 2-stage (HR = 1.6; 95% CI: 0.9-3.1) procedures. Reconstruction failure was highest (13.2%) in the 2-stage procedures with a history of radiation therapy. Breast...... reconstruction approaches other than implants should be seriously considered among women who have received radiation therapy....

  1. Delay tolerant networks

    CERN Document Server

    Gao, Longxiang; Luan, Tom H

    2015-01-01

    This brief presents emerging and promising communication methods for network reliability via delay tolerant networks (DTNs). Different from traditional networks, DTNs possess unique features, such as long latency and unstable network topology. As a result, DTNs can be widely applied to critical applications, such as space communications, disaster rescue, and battlefield communications. The brief provides a complete investigation of DTNs and their current applications, from an overview to the latest development in the area. The core issue of data forward in DTNs is tackled, including the importance of social characteristics, which is an essential feature if the mobile devices are used for human communication. Security and privacy issues in DTNs are discussed, and future work is also discussed.

  2. World lines.

    OpenAIRE

    Waser Jürgen; Fuchs Raphael; Ribicic Hrvoje; Schindler Benjamin; Blöschl Günther; Gröller Eduard

    2010-01-01

    In this paper we present World Lines as a novel interactive visualization that provides complete control over multiple heterogeneous simulation runs. In many application areas decisions can only be made by exploring alternative scenarios. The goal of the suggested approach is to support users in this decision making process. In this setting the data domain is extended to a set of alternative worlds where only one outcome will actually happen. World Lines integrate simulation visualization and...

  3. Delay in the diagnosis of cancer

    DEFF Research Database (Denmark)

    Hansen, Rikke Pilegaard

    for a detailed description of the patients' diagnostic pathways, allowing the researchers to draw the time line from symptom onset to treatment start, and to describe the characteristics of the patients and the GPs. Existing scales were used whenever possible; otherwise, ad hoc questions were constructed....... Chaper 1 introduces the concept of delay in the diagnosis of cancer. The chapter aims to provide insight into the time interval from symptom to treatment and into the patient and GP characteristics that potentially influence this interval. In addition, the chapter gives a brief overview of cancer...

  4. Location Estimation using Delayed Measurements

    DEFF Research Database (Denmark)

    Bak, Martin; Larsen, Thomas Dall; Nørgård, Peter Magnus

    1998-01-01

    When combining data from various sensors it is vital to acknowledge possible measurement delays. Furthermore, the sensor fusion algorithm, often a Kalman filter, should be modified in order to handle the delay. The paper examines different possibilities for handling delays and applies a new techn...... technique to a sensor fusion system for estimating the location of an autonomous guided vehicle. The system fuses encoder and vision measurements in an extended Kalman filter. Results from experiments in a real environment are reported...

  5. Modeling delay in genetic networks: from delay birth-death processes to delay stochastic differential equations.

    Science.gov (United States)

    Gupta, Chinmaya; López, José Manuel; Azencott, Robert; Bennett, Matthew R; Josić, Krešimir; Ott, William

    2014-05-28

    Delay is an important and ubiquitous aspect of many biochemical processes. For example, delay plays a central role in the dynamics of genetic regulatory networks as it stems from the sequential assembly of first mRNA and then protein. Genetic regulatory networks are therefore frequently modeled as stochastic birth-death processes with delay. Here, we examine the relationship between delay birth-death processes and their appropriate approximating delay chemical Langevin equations. We prove a quantitative bound on the error between the pathwise realizations of these two processes. Our results hold for both fixed delay and distributed delay. Simulations demonstrate that the delay chemical Langevin approximation is accurate even at moderate system sizes. It captures dynamical features such as the oscillatory behavior in negative feedback circuits, cross-correlations between nodes in a network, and spatial and temporal information in two commonly studied motifs of metastability in biochemical systems. Overall, these results provide a foundation for using delay stochastic differential equations to approximate the dynamics of birth-death processes with delay.

  6. Modeling delay in genetic networks: From delay birth-death processes to delay stochastic differential equations

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Chinmaya; López, José Manuel; Azencott, Robert; Ott, William [Department of Mathematics, University of Houston, Houston, Texas 77004 (United States); Bennett, Matthew R. [Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77204, USA and Institute of Biosciences and Bioengineering, Rice University, Houston, Texas 77005 (United States); Josić, Krešimir [Department of Mathematics, University of Houston, Houston, Texas 77004 (United States); Department of Biology and Biochemistry, University of Houston, Houston, Texas 77204 (United States)

    2014-05-28

    Delay is an important and ubiquitous aspect of many biochemical processes. For example, delay plays a central role in the dynamics of genetic regulatory networks as it stems from the sequential assembly of first mRNA and then protein. Genetic regulatory networks are therefore frequently modeled as stochastic birth-death processes with delay. Here, we examine the relationship between delay birth-death processes and their appropriate approximating delay chemical Langevin equations. We prove a quantitative bound on the error between the pathwise realizations of these two processes. Our results hold for both fixed delay and distributed delay. Simulations demonstrate that the delay chemical Langevin approximation is accurate even at moderate system sizes. It captures dynamical features such as the oscillatory behavior in negative feedback circuits, cross-correlations between nodes in a network, and spatial and temporal information in two commonly studied motifs of metastability in biochemical systems. Overall, these results provide a foundation for using delay stochastic differential equations to approximate the dynamics of birth-death processes with delay.

  7. Modeling delay in genetic networks: From delay birth-death processes to delay stochastic differential equations

    International Nuclear Information System (INIS)

    Gupta, Chinmaya; López, José Manuel; Azencott, Robert; Ott, William; Bennett, Matthew R.; Josić, Krešimir

    2014-01-01

    Delay is an important and ubiquitous aspect of many biochemical processes. For example, delay plays a central role in the dynamics of genetic regulatory networks as it stems from the sequential assembly of first mRNA and then protein. Genetic regulatory networks are therefore frequently modeled as stochastic birth-death processes with delay. Here, we examine the relationship between delay birth-death processes and their appropriate approximating delay chemical Langevin equations. We prove a quantitative bound on the error between the pathwise realizations of these two processes. Our results hold for both fixed delay and distributed delay. Simulations demonstrate that the delay chemical Langevin approximation is accurate even at moderate system sizes. It captures dynamical features such as the oscillatory behavior in negative feedback circuits, cross-correlations between nodes in a network, and spatial and temporal information in two commonly studied motifs of metastability in biochemical systems. Overall, these results provide a foundation for using delay stochastic differential equations to approximate the dynamics of birth-death processes with delay

  8. Systematic of delayed neutron parameters

    International Nuclear Information System (INIS)

    Isaev, S.G.; Piksaikin, V.M.

    2000-01-01

    The experimental studies of the energy dependence of the delayed neutron (DN) parameters for various fission systems has shown that the behaviour of a some combination of delayed neutron parameters has a similar features. On the basis of this findings the systematics of delayed neutron experimental data for thorium, uranium, plutonium and americium isotopes have been investigated with the purpose to find a correlation of DN parameters with characteristics of fissioning system as well as a correlation between the delayed neutron parameters themselves. It was presented the preliminary results which were obtained during study the physics interpretation of the results [ru

  9. Time Delay of CGM Sensors

    Science.gov (United States)

    Schmelzeisen-Redeker, Günther; Schoemaker, Michael; Kirchsteiger, Harald; Freckmann, Guido; Heinemann, Lutz; del Re, Luigi

    2015-01-01

    Background: Continuous glucose monitoring (CGM) is a powerful tool to support the optimization of glucose control of patients with diabetes. However, CGM systems measure glucose in interstitial fluid but not in blood. Rapid changes in one compartment are not accompanied by similar changes in the other, but follow with some delay. Such time delays hamper detection of, for example, hypoglycemic events. Our aim is to discuss the causes and extent of time delays and approaches to compensate for these. Methods: CGM data were obtained in a clinical study with 37 patients with a prototype glucose sensor. The study was divided into 5 phases over 2 years. In all, 8 patients participated in 2 phases separated by 8 months. A total number of 108 CGM data sets including raw signals were used for data analysis and were processed by statistical methods to obtain estimates of the time delay. Results: Overall mean (SD) time delay of the raw signals with respect to blood glucose was 9.5 (3.7) min, median was 9 min (interquartile range 4 min). Analysis of time delays observed in the same patients separated by 8 months suggests a patient dependent delay. No significant correlation was observed between delay and anamnestic or anthropometric data. The use of a prediction algorithm reduced the delay by 4 minutes on average. Conclusions: Prediction algorithms should be used to provide real-time CGM readings more consistent with simultaneous measurements by SMBG. Patient specificity may play an important role in improving prediction quality. PMID:26243773

  10. Radiosensitivity of mesothelioma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Haekkinen, A.M. [Dept. of Oncology, Univ. Central Hospital, Helsinki (Finland); Laasonen, A. [Dept. of Pathology, Central Hospital of Etelae-Pohjanmaa, Seinaejoki (Finland); Linnainmaa, K. [Dept. of Industrial Hygiene and Toxicology, Inst. of Occupational Health, Helsinki (Finland); Mattson, K. [Dept. Pulmonary Medicine, Univ. Central Hospital, Helsinki (Finland); Pyrhoenen, S. [Dept. of Oncology, Univ. Central Hospital, Helsinki (Finland)

    1996-10-01

    The present study was carried out in order to examine the radiosensitivity of malignant pleural mesothelioma cell lines. Cell kinetics, radiation-induced delay of the cell cycle and DNA ploidy of the cell lines were also determined. For comparison an HeLa and a human foetal fibroblast cell line were simultaneously explored. Six previously cytogenetically and histologically characterized mesothelioma tumor cell lines were applied. A rapid tiazolyl blue microtiter (MTT) assay was used to analyze radiosensitivity and cell kinetics and DNA ploidy of the cultured cells were determined by flow cytometry. The survival fraction after a dose of 2 Gy (SF2), parameters {alpha} and {beta} of the linear quadratic model (LQ-model) and mean inactivation dose (D{sub MID}) were also estimated. The DNA index of four cell lines equaled 1.0 and two cell lines equaled 1.5 and 1.6. Different mesothelioma cell lines showed a great variation in radiosensitivity. Mean survival fraction after a radiation dose of 2 Gy (SF2) was 0.60 and ranged from 0.36 to 0.81 and mean {alpha} value was 0.26 (range 0.48-0.083). The SF2 of the most sensitive diploid mesothelioma cell line was 0.36: Less than that of the foetal fibroblast cell line (0.49). The survival fractions (0.81 and 0.74) of the two most resistant cell lines, which also were aneuploid, were equal to that of the HeLa cell line (0.78). The {alpha}/{beta} ratios of the most sensitive cell lines were almost an order of magnitude greater than those of the two most resistant cell lines. Radiation-induced delay of the most resistant aneuploid cell line was similar to that of HeLa cells but in the most sensitive (diploid cells) there was practically no entry into the G1 phase following the 2 Gy radiation dose during 36 h. (orig.).

  11. Silver linings.

    Science.gov (United States)

    Bultas, Margaret W; Pohlman, Shawn

    2014-01-01

    The purpose of this interpretive phenomenological study was to gain a better understanding of the experiences of 11 mothers of preschool children with autism spectrum disorder (ASD). Mothers were interviewed three times over a 6 week period. Interviews were analyzed using interpretive methods. This manuscript highlights one particular theme-a positive perspective mothers described as the "silver lining." This "silver lining" represents optimism despite the adversities associated with parenting a child with ASD. A deeper understanding of this side of mothering children with ASD may help health care providers improve rapport, communication, and result in more authentic family centered care. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Application of data clustering to railway delay pattern recognition

    DEFF Research Database (Denmark)

    Cerreto, Fabrizio; Nielsen, Bo Friis; Nielsen, Otto Anker

    2018-01-01

    K-means clustering is employed to identify recurrent delay patterns on a high traffic railway line north of Copenhagen, Denmark. The clusters identify behavioral patterns in the very large (“big data”) data sets generated automatically and continuously by the railway signal system. The results re...

  13. Optical resonators for true-time-delay beam steering

    Science.gov (United States)

    Gesell, Leslie H.; Evanko, Stephen M.

    1996-06-01

    Conventional true time delay beamforming and steering devices rely on switching between various lengths of delay line. Therefore only discrete delays are possible. Proposed is a new photonics concept for true time delay beamforming which provides a finely controlled continuum of delays with switching speeds on the order of 10's of nanoseconds or faster. The architecture uses an array of waveguide cavities with different resonate frequencies to channelize the signal. Each spectral component of the signal is phase shifted by an amount proportional to the frequency of that component and the desired time delay. These phase shifted spectral components are then summed to obtain the delayed signal. This paper provides an overview of the results of a Phase I SBIR contract where this concept has been refined and analyzed. The parameters for an operational system are determined and indication of the feasibility of this approach is given. Among the issues addressed are the requirements of the resonators and the methods necessary to implement fiber optic Bragg gratings as these resonators.

  14. Delayed Auditory Feedback and Movement

    Science.gov (United States)

    Pfordresher, Peter Q.; Dalla Bella, Simone

    2011-01-01

    It is well known that timing of rhythm production is disrupted by delayed auditory feedback (DAF), and that disruption varies with delay length. We tested the hypothesis that disruption depends on the state of the movement trajectory at the onset of DAF. Participants tapped isochronous rhythms at a rate specified by a metronome while hearing DAF…

  15. #FakeNobelDelayReasons

    CERN Multimedia

    2013-01-01

    Tuesday’s hour-long delay of the Nobel Prize in Physics announcement was (and still is) quite the cause for speculation. But on the Twittersphere, it was simply the catalyst for some fantastic puns, so-bad-they're-good physics jokes and other shenanigans. Here are some of our favourite #FakeNobelDelayReasons.    

  16. Project delay analysis of HRSG

    Science.gov (United States)

    Silvianita; Novega, A. S.; Rosyid, D. M.; Suntoyo

    2017-08-01

    Completion of HRSG (Heat Recovery Steam Generator) fabrication project sometimes is not sufficient with the targeted time written on the contract. The delay on fabrication process can cause some disadvantages for fabricator, including forfeit payment, delay on HRSG construction process up until HRSG trials delay. In this paper, the author is using semi quantitative on HRSG pressure part fabrication delay with configuration plant 1 GT (Gas Turbine) + 1 HRSG + 1 STG (Steam Turbine Generator) using bow-tie analysis method. Bow-tie analysis method is a combination from FTA (Fault tree analysis) and ETA (Event tree analysis) to develop the risk matrix of HRSG. The result from FTA analysis is use as a threat for preventive measure. The result from ETA analysis is use as impact from fabrication delay.

  17. Delayed radiation neuropathy

    Energy Technology Data Exchange (ETDEWEB)

    Nagashima, T.; Miyamoto, K.; Beppu, H.; Hirose, K.; Yamada, K. (Tokyo Metropolitan Neurological Hospital (Japan))

    1981-07-01

    A case of cervical plexus neuropathy was reported in association with chronic radio-dermatitis, myxedema with thyroid adenoma and epiglottic tumor. A 38-year-old man has noticed muscle weakness and wasting of the right shoulder girdle since age 33. A detailed history taking revealed a previous irradiation to the neck because of the cervical lymphadenopathy at age 10 (X-ray 3,000 rads), keroid skin change at age 19, obesity and edema since 26, and hoarseness at 34. Laryngoscopic examination revealed a tumor on the right vocal cord, diagnosed as benign papilloma by histological study. In addition, there were chronic radio-dermatitis around the neck, primary hypothyroidism with a benign functioning adenoma on the right lobe of the thyroid, the right phrenic nerve palsy and the right recurrent nerve palsy. All these lesions were considered to be the late sequellae of radiation to the neck in childhood. Other neurological signs were weakness and amyotrophy of the right shoulder girdle with patchy sensory loss, and areflexia of the right arm. Gross power was fairly well preserved in the right hand. EMG showed neurogenic changes in the tested muscles, suggesting a peripheral nerve lesion. Nerve conduction velocities were normal. No abnormal findings were revealed by myelography and spinal CT. The neurological findings of the patient were compatible with the diagnosis of middle cervical plexus palsy apparently due to late radiation effect. In the literature eight cases of post-radiation neuropathy with a long latency have been reported. The present case with the longest latency after the radiation should be included in the series of the reported cases of ''delayed radiation neuropathy.'' (author).

  18. Delayed radiation neuropathy

    International Nuclear Information System (INIS)

    Nagashima, Toshiko; Miyamoto, Kazuto; Beppu, Hirokuni; Hirose, Kazuhiko; Yamada, Katsuhiro

    1981-01-01

    A case of cervical plexus neuropathy was reported in association with chronic radio-dermatitis, myxedema with thyroid adenoma and epiglottic tumor. A 38-year-old man has noticed muscle weakness and wasting of the right shoulder girdle since age 33. A detailed history taking revealed a previous irradiation to the neck because of the cervical lymphadenopathy at age 10 (X-ray 3,000 rads), keroid skin change at age 19, obesity and edema since 26, and hoarseness at 34. Laryngoscopic examination revealed a tumor on the right vocal cord, diagnosed as benign papilloma by histological study. In addition, there were chronic radio-dermatitis around the neck, primary hypothyroidism with a benign functioning adenoma on the right lobe of the thyroid, the right phrenic nerve palsy and the right recurrent nerve palsy. All these lesions were considered to be the late sequellae of radiation to the neck in childhood. Other neurological signs were weakness and amyotrophy of the right shoulder girdle with patchy sensory loss, and areflexia of the right arm. Gross power was fairly well preserved in the right hand. EMG showed neurogenic changes in the tested muscles, suggesting a peripheral nerve lesion. Nerve conduction velocities were normal. No abnormal findings were revealed by myelography and spinal CT. The neurological findings of the patient were compatible with the diagnosis of middle cervical plexus palsy apparently due to late radiation effect. In the literature eight cases of post-radiation neuropathy with a long latency have been reported. The present case with the longest latency after the radiation should be included in the series of the reported cases of ''delayed radiation neuropathy.'' (author)

  19. High-Resolution Digital-to-Time Converter Implemented in an FPGA Chip

    Directory of Open Access Journals (Sweden)

    Hai Wang

    2017-01-01

    Full Text Available This paper presents the design and implementation of a new digital-to-time converter (DTC. The obtained resolution is 1.02 ps, and the dynamic range is about 590 ns. The experimental results indicate that the measured differential nonlinearity (DNL and integral nonlinearity (INL are −0.17~+0.13 LSB and −0.35~+0.62 LSB, respectively. This DTC builds coarse and fine Vernier delay lines constructed by programmable delay lines (PDLs to ensure high performance delay. Benefited by the close-loop feedback mechanism of the PDLs’ control module, the presented DTC has excellent voltage and temperature stability. What is more, the proposed DTC can be implemented in a single field programmable gate array (FPGA chip.

  20. Attosecond Delays in Molecular Photoionization.

    Science.gov (United States)

    Huppert, Martin; Jordan, Inga; Baykusheva, Denitsa; von Conta, Aaron; Wörner, Hans Jakob

    2016-08-26

    We report measurements of energy-dependent photoionization delays between the two outermost valence shells of N_{2}O and H_{2}O. The combination of single-shot signal referencing with the use of different metal foils to filter the attosecond pulse train enables us to extract delays from congested spectra. Remarkably large delays up to 160 as are observed in N_{2}O, whereas the delays in H_{2}O are all smaller than 50 as in the photon-energy range of 20-40 eV. These results are interpreted by developing a theory of molecular photoionization delays. The long delays measured in N_{2}O are shown to reflect the population of molecular shape resonances that trap the photoelectron for a duration of up to ∼110 as. The unstructured continua of H_{2}O result in much smaller delays at the same photon energies. Our experimental and theoretical methods make the study of molecular attosecond photoionization dynamics accessible.

  1. Menstrual management in developmentally delayed adolescent females.

    Science.gov (United States)

    Chuah, Irene; McRae, Alexandra; Matthews, Kim; Maguire, Ann M; Steinbeck, Katharine

    2017-06-01

    Requests for assistance in menstrual management and menstrual suppression are a common, emotive and sometimes controversial aspect of adolescent disability care. To review the uptake and outcomes of menstrual suppression among adolescent patients with developmental delay. A retrospective review of the medical records of adolescent females with intellectual disability referred for menstrual management to the Paediatric and Adolescent Gynaecology Clinic, Children's Hospital at Westmead, Sydney, for the three-year period between January 1, 2010 and January 1, 2013. Eighty adolescent patients with developmental delay were identified. A third (n = 28) of the patients were pre-menarcheal at first review with parent/caregivers seeking anticipatory advice. Of the post-menarcheal patients, the median age of menarche was 12 years (range 10-15 years). First and second line interventions were documented as were reasons for change where applicable. The combined oral contraceptive pill (COCP) was the most frequently used therapy (67%), and 19 patients in total had a levonorgestrel releasing intrauterine system (LNG-IUS) inserted (31%). Our study population differs from similar previously published groups in the marked absence of the use of depot medroxyprogesterone acetate or the subdermal etonogestrel releasing device. As a paediatrician, it is important to address menstrual management issues and allay caregiver concerns with appropriate advice. Our study supports the use of the COCP as sound first line management in achieving menstrual suppression. The LNG-IUS appears to be a favourable second line option. Further investigation into longer-term outcomes and potential complications of device insertion is recommended. © 2017 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  2. Break-before-make CMOS inverter for power-efficient delay implementation.

    Science.gov (United States)

    Puhan, Janez; Raič, Dušan; Tuma, Tadej; Bűrmen, Árpád

    2014-01-01

    A modified static CMOS inverter with two inputs and two outputs is proposed to reduce short-circuit current in order to increment delay and reduce power overhead where slow operation is required. The circuit is based on bidirectional delay element connected in series with the PMOS and NMOS switching transistors. It provides differences in the dynamic response so that the direct-path current in the next stage is reduced. The switching transistors are never ON at the same time. Characteristics of various delay element implementations are presented and verified by circuit simulations. Global optimization procedure is used to obtain the most power-efficient transistor sizing. The performance of the modified CMOS inverter chain is compared to standard implementation for various delays. The energy (charge) per delay is reduced up to 40%. The use of the proposed delay element is demonstrated by implementing a low-power delay line and a leading-edge detector cell.

  3. Delays and networked control systems

    CERN Document Server

    Hetel, Laurentiu; Daafouz, Jamal; Johansson, Karl

    2016-01-01

    This edited monograph includes state-of-the-art contributions on continuous time dynamical networks with delays. The book is divided into four parts. The first part presents tools and methods for the analysis of time-delay systems with a particular attention on control problems of large scale or infinite-dimensional systems with delays. The second part of the book is dedicated to the use of time-delay models for the analysis and design of Networked Control Systems. The third part of the book focuses on the analysis and design of systems with asynchronous sampling intervals which occur in Networked Control Systems. The last part of the book exposes several contributions dealing with the design of cooperative control and observation laws for networked control systems. The target audience primarily comprises researchers and experts in the field of control theory, but the book may also be beneficial for graduate students. .

  4. production lines

    Directory of Open Access Journals (Sweden)

    Jingshan Li

    2000-01-01

    Full Text Available In this work, serial production lines with finished goods buffers operating in the pull regime are considered. The machines are assumed to obey Bernoulli reliability model. The problem of satisfying customers demand is addressed. The level of demand satisfaction is quantified by the due-time performance (DTP, which is defined as the probability to ship to the customer a required number of parts during a fixed time interval. Within this scenario, the definitions of DTP bottlenecks are introduced and a method for their identification is developed.

  5. Systematics in delayed neutron yields

    Energy Technology Data Exchange (ETDEWEB)

    Ohsawa, Takaaki [Kinki Univ., Higashi-Osaka, Osaka (Japan). Atomic Energy Research Inst.

    1998-03-01

    An attempt was made to reproduce the systematic trend observed in the delayed neutron yields for actinides on the basis of the five-Gaussian representation of the fission yield together with available data sets for delayed neutron emission probability. It was found that systematic decrease in DNY for heavier actinides is mainly due to decrease of fission yields of precursors in the lighter side of the light fragment region. (author)

  6. Analytical applications for delayed neutrons

    International Nuclear Information System (INIS)

    Eccleston, G.W.

    1983-01-01

    Analytical formulations that describe the time dependence of neutron populations in nuclear materials contain delayed-neutron dependent terms. These terms are important because the delayed neutrons, even though their yields in fission are small, permit control of the fission chain reaction process. Analytical applications that use delayed neutrons range from simple problems that can be solved with the point reactor kinetics equations to complex problems that can only be solved with large codes that couple fluid calculations with the neutron dynamics. Reactor safety codes, such as SIMMER, model transients of the entire reactor core using coupled space-time neutronics and comprehensive thermal-fluid dynamics. Nondestructive delayed-neutron assay instruments are designed and modeled using a three-dimensional continuous-energy Monte Carlo code. Calculations on high-burnup spent fuels and other materials that contain a mix of uranium and plutonium isotopes require accurate and complete information on the delayed-neutron periods, yields, and energy spectra. A continuing need exists for delayed-neutron parameters for all the fissioning isotopes

  7. Line facilities outline

    International Nuclear Information System (INIS)

    1998-08-01

    This book deals with line facilities. The contents of this book are outline line of wire telecommunication ; development of line, classification of section of line and theory of transmission of line, cable line ; structure of line, line of cable in town, line out of town, domestic cable and other lines, Optical communication ; line of optical cable, transmission method, measurement of optical communication and cable of the sea bottom, Equipment of telecommunication line ; telecommunication line facilities and telecommunication of public works, construction of cable line and maintenance and Regulation of line equipment ; regulation on technique, construction and maintenance.

  8. Delayed luminescence in a multiparameter approach to evaluation and reduction of radiobiological risks

    Science.gov (United States)

    Grasso, Rosaria; Cammarata, Francesco Paolo; Minafra, Luigi; Marchese, Valentina; Russo, Giorgio; Manti, Lorenzo; Musumeci, Francesco; Scordino, Agata

    2017-07-01

    In the framework of the research project ETHICS "Pre-clinical experimental and theoretical studies to improve treatment and protection by charged particles" funded by the National Nuclear Physics Institute, Italy, we studied the phenomenon called delayed luminescence emitted by non-tumorigenic breast epithelial MCF10A cell line after proton irradiation at different doses (0.5, 2, 6, 9 Gy). The aim is to found possible correlations between delayed luminescence and in vitro damaging induced by ion irradiation. The first results of this research show that the delayed luminescence kinetics is proton dose dependent. An interesting correlation between delayed luminescence and clonogenic potential was observed.

  9. Parallel Lines

    Directory of Open Access Journals (Sweden)

    James G. Worner

    2017-05-01

    Full Text Available James Worner is an Australian-based writer and scholar currently pursuing a PhD at the University of Technology Sydney. His research seeks to expose masculinities lost in the shadow of Australia’s Anzac hegemony while exploring new opportunities for contemporary historiography. He is the recipient of the Doctoral Scholarship in Historical Consciousness at the university’s Australian Centre of Public History and will be hosted by the University of Bologna during 2017 on a doctoral research writing scholarship.   ‘Parallel Lines’ is one of a collection of stories, The Shapes of Us, exploring liminal spaces of modern life: class, gender, sexuality, race, religion and education. It looks at lives, like lines, that do not meet but which travel in proximity, simultaneously attracted and repelled. James’ short stories have been published in various journals and anthologies.

  10. Beta-delayed neutron decay of $^{33}$Na

    CERN Document Server

    Radivojevic, Z; Caurier, E; Cederkäll, J; Courtin, S; Dessagne, P; Jokinen, A; Knipper, A; Le Scornet, G; Lyapin, V G; Miehé, C; Nowacki, F; Nummela, S; Oinonen, M; Poirier, E; Ramdhane, M; Trzaska, W H; Walter, G; Äystö, J

    2002-01-01

    Beta-delayed neutron decay of /sup 33/Na has been studied using the on-line mass separator ISOLDE. The delayed neutron spectra were measured by time-of-flight technique using fast scintillators. Two main neutron groups at 800(60) and 1020(80) keV were assigned to the /sup 33/Na decay, showing evidence for strong feeding of states at about 4 MeV in /sup 33/Mg. By simultaneous beta - gamma -n counting the delayed neutron emission probabilities P/sub 1n/ = 47(6)% and P /sub 2n/ = 13(3)% were determined. The half-life value for /sup 33 /Na, T/sub 1/2/ = 8.0(3) ms, was measured by three different techniques, one employing identifying gamma transitions and two employing beta and neutron counting. (21 refs).

  11. Delay Estimator and Improved Proportionate Multi-Delay Adaptive Filtering Algorithm

    Directory of Open Access Journals (Sweden)

    E. Verteletskaya

    2012-04-01

    Full Text Available This paper pertains to speech and acoustic signal processing, and particularly to a determination of echo path delay and operation of echo cancellers. To cancel long echoes, the number of weights in a conventional adaptive filter must be large. The length of the adaptive filter will directly affect both the degree of accuracy and the convergence speed of the adaptation process. We present a new adaptive structure which is capable to deal with multiple dispersive echo paths. An adaptive filter according to the present invention includes means for storing an impulse response in a memory, the impulse response being indicative of the characteristics of a transmission line. It also includes a delay estimator for detecting ranges of samples within the impulse response having relatively large distribution of echo energy. These ranges of samples are being indicative of echoes on the transmission line. An adaptive filter has a plurality of weighted taps, each of the weighted taps having an associated tap weight value. A tap allocation/control circuit establishes the tap weight values in response to said detecting means so that only taps within the regions of relatively large distributions of echo energy are turned on. Thus, the convergence speed and the degree of estimation in the adaptation process can be improved.

  12. UWB delay and multiply receiver

    Energy Technology Data Exchange (ETDEWEB)

    Dallum, Gregory E.; Pratt, Garth C.; Haugen, Peter C.; Romero, Carlos E.

    2013-09-10

    An ultra-wideband (UWB) delay and multiply receiver is formed of a receive antenna; a variable gain attenuator connected to the receive antenna; a signal splitter connected to the variable gain attenuator; a multiplier having one input connected to an undelayed signal from the signal splitter and another input connected to a delayed signal from the signal splitter, the delay between the splitter signals being equal to the spacing between pulses from a transmitter whose pulses are being received by the receive antenna; a peak detection circuit connected to the output of the multiplier and connected to the variable gain attenuator to control the variable gain attenuator to maintain a constant amplitude output from the multiplier; and a digital output circuit connected to the output of the multiplier.

  13. Chaos in the delay logistic equation with discontinuous delays

    International Nuclear Information System (INIS)

    Sen, Ayan; Mukherjee, Debasis

    2009-01-01

    This paper analyzes a delay logistic equation which models a feedback control problem. Interval map associated to the system is derived. By calculating Lyapunov exponent, we indicate stable orbit and chaotic phenomenon respectively. The results are verified through computer simulation. We identify the parameter which controls the dynamics.

  14. A clock and data recovery method based on phase detector implemented by delay chain in FPGA

    International Nuclear Information System (INIS)

    Xie Mingpu; Wu Jie; Zhang Jie

    2009-01-01

    A clock and data recovery method based on charge pump PLL was developed to archive medium data rate serial digital communication with simple line transceivers. The phase detector was realized by FPGA. A delay chain was constructed by delay elements with the same fixed delay. Every output of the delay elements was latched by the VCO output clock when the input signal went through the delay chain. The latched result was used to detect the data transition, which reflected the phase difference between the input signal and the VCO output clock. The VCO control voltage was adjust by charge pump to reduce the phase difference and archive phase lock. The loop filter was a passive filter,parameters of which were calculated from parameters of the delay chain and VCO. The experimental result shows that the clock of a 64Mbps transmission was recovered with a jitter less than 200 ps. (authors)

  15. Postraumatic delayed loss of vision

    International Nuclear Information System (INIS)

    Partington, C.R.; Graves, V.B.; Ruetenacht, D.A.; Weinstein, J.M.; Strother, C.M.

    1989-01-01

    The imaging studies and clinical findings in 10 patients who suffered delayed vision loss beginning 1 day to 13 years after head trauma have been reviewed. Two different primary lesions could be identified: pseudoaneurysm of the internal carotid artery and carotid cavernous fistula. The pathologic changes associated with pseudoaneurysm included compression of the optic nerves and/or chiasm by arterial aneurysm and intracranial hematoma. Carotid cavernous fistula caused delayed vision loss by compression of the optic nerves and chiasm by saccular dilatation of the cavernous sinus and by abnormal orbital venous drainage with retinal venous stasis, retinal edema, and glaucoma

  16. Time delayed Ensemble Nudging Method

    Science.gov (United States)

    An, Zhe; Abarbanel, Henry

    Optimal nudging method based on time delayed embedding theory has shows potentials on analyzing and data assimilation in previous literatures. To extend the application and promote the practical implementation, new nudging assimilation method based on the time delayed embedding space is presented and the connection with other standard assimilation methods are studied. Results shows the incorporating information from the time series of data can reduce the sufficient observation needed to preserve the quality of numerical prediction, making it a potential alternative in the field of data assimilation of large geophysical models.

  17. 49 CFR 236.563 - Delay time.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Delay time. 236.563 Section 236.563 Transportation... Cab Signal Systems Rules and Instructions; Locomotives § 236.563 Delay time. Delay time of automatic... requirements of § 236.24 shall take into consideration the delay time. ...

  18. VT Digital Line Graph Miscellaneous Transmission Lines

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This datalayer is comprised of Miscellaineous Transmission Lines. Digital line graph (DLG) data are digital representations of cartographic...

  19. Laser homeostatics on delayed onset muscle soreness

    Energy Technology Data Exchange (ETDEWEB)

    Liu, T C Y; Fu, D R; Liu, X G; Tian, Z X, E-mail: liutcy@scnu.edu.cn [Lab Laser Sports Medicine, South China Normal University, University Town, Guangzhou, GD 510006 (China)

    2011-01-01

    Delayed onset muscle soreness (DOMS) and its photobiomodulation were reviewed from the viewpoint of function-specific homeostasis (FSH) in this paper. FSH is a negative-feedback response of a biosystem to maintain the function-specific fluctuations inside the biosystem so that the function is perfectly performed. A stressor may destroy a FSH. A stress is a response of a biosystem to a stressor and may also be in stress-specific homeostasis (StSH). A low level light (LLL) is so defined that it has no effects on a function in its FSH or a stress in its StSH, but it modulate a function far from its FSH or a stress far from its StSH. For DOMS recovery, protein metabolism in the Z-line streaming muscular cell is the essential process, but the inflammation, pain and soreness are non-essential processes. For many DOMS phenomena, protein metabolism in the Z-line streaming muscular cell is in protein metabolism-specific homeostasis (PmSH) so that there are no effects of LLL although the inflammation can be inhibited and the pain can be relieved. An athlete or animal in the dysfunctional conditions such as blood flow restriction and exercise exhaustion is far from PmSH and the protein metabolism can be improved with LLL.

  20. Early-delayed radiation rhombencephalopathy

    International Nuclear Information System (INIS)

    Nightingale, S.; Dawes, P.J.D.K.; Cartlidge, N.E.F.; Newcastle upon Tyne Univ.

    1982-01-01

    A 37-year-old woman developed an early-delayed rhombencephalopathy 7 weeks after completing a course of radiotherapy to a glomus jugulare tumour. The clinical features, comprising nystagmus, skew strabismus, unilateral facial weakness, dysarthria and ataxia, are compared with four previously reported patients with this syndrome. (author)

  1. Another definition for time delay

    International Nuclear Information System (INIS)

    Narnhofer, H.

    1980-01-01

    Time delay is defined by geometrical considerations which work in classical as well as in quantum mechanics, and its connection with the S-matrix and the virial is proven for potentials with V(x vector) and x vector V(x vector) vanishing as rsup(-1-epsilon) for r -> infinity. (Author)

  2. Weather delay costs to trucking.

    Science.gov (United States)

    2012-11-01

    Estimates of the nations freight sector of transportation range to upwards of $600 billion of total gross domestic product with 70 percent of total value and 60 percent of total weight moving by truck. Weather-related delays can add significantly ...

  3. Diagnostic Delay in Rheumatoid Arthritis

    DEFF Research Database (Denmark)

    Mølbaek, Karen; Hørslev-Petersen, Kim; Primdahl, Jette

    2016-01-01

    BACKGROUND: To prevent joint damage among patients with rheumatoid arthritis (RA), there is a need to minimize delays from the onset of symptoms until the initiation of appropriate therapy. The present study explored the factors that have an impact on the time it takes for Danish patients with RA...

  4. Design flaw could delay collider

    CERN Multimedia

    Cho, Adrian

    2007-01-01

    "A magnet for the Large Hadron Collider (LHC) failed during a key test at the European particle physics laboratory CERN last week. Physicists and engineers will have to repair the damaged magnet and retrofit others to correct the underlynig design flaw, which could delay the start-up of the mammouth subterranean machine." (1,5 page)

  5. Concurrent Delay in Construction Disputes

    DEFF Research Database (Denmark)

    Cavaleri, Sylvie Cécile

    the delay is contractually defined as a contractor's risk, the contractor is liable to pay liquidated damages to the employer; if it is not, the contractor can under certain circumstances claim an extension of time and in some cases also economic compensation from the employer. The situation where a given...

  6. Deconstructing delayed posttraumatic stress disorder

    NARCIS (Netherlands)

    Smid, G

    2011-01-01

    According to the Diagnostic and Statistical Manual of Mental Disorders, delayed posttraumatic stress disorder (PTSD) must be diagnosed in individuals fulfilling criteria for PTSD if the onset of symptoms is at least six months after the trauma. The purpose of this thesis was to establish the

  7. Livermore blasted for project delay

    CERN Multimedia

    1999-01-01

    In a 12 page report issued last week, a review committee set up by the University of California has concluded that mismanagement and poor planning are to blame for significant cost overruns and delays in the construction of NIF, the worlds largest laser (1 page).

  8. Providing delay guarantees in Bluetooth

    NARCIS (Netherlands)

    Ait Yaiz, R.; Heijenk, Geert; Titsworth, F.

    2003-01-01

    Bluetooth polling, also referred to as Bluetooth MAC scheduling or intra-piconet scheduling, is the mechanism that schedules the traffic between the participants in a Bluetooth network. Hence, this mechanism is highly determining with respect to the delay packets experience in a Bluetooth network.

  9. The U-line line balancing problem

    NARCIS (Netherlands)

    Miltenburg, G.J.; Wijngaard, J.

    1994-01-01

    The traditional line balancing (LB) problem considers a production line in which stations are arranged consecutively in a line. A balance is determined by grouping tasks into stations while moving forward (or backward) through a precedence network. Recently many production lines are being arranged

  10. Analysis of a first-order delay differential-delay equation containing two delays

    Science.gov (United States)

    Marriott, C.; Vallée, R.; Delisle, C.

    1989-09-01

    An experimental and numerical analysis of the behavior of a two-delay differential equation is presented. It is shown that much of the system's behavior can be related to the stability behavior of the underlying linearized modes. A new phenomenon, mode crossing, is explored.

  11. Requirements and guidelines for NSLS experimental beam line vacuum systems: Revision A

    International Nuclear Information System (INIS)

    Foerster, C.; Halama, H.; Thomlinson, W.

    1986-10-01

    Requirements are provided for NSLS beam line front ends and vacuum interlocks. Guidelines are provided for UHV beam line vacuum systems, including materials, vacuum hardware (pumps, valves, and flanges), acoustic delay lines and beam line fast valves, instrumentation, fabrication and testing, and the NSLS cleaning facility. Also discussed are the design review for experimenters' equipment that would be connected to the NSLS and acceptance tests for any beam line to be connected with the ring vacuum. Also appended are a description of the acoustic delay line as well as the NSLS vacuum standards and NSLS procedures

  12. Analytical determination of the bifurcation thresholds in stochastic differential equations with delayed feedback.

    Science.gov (United States)

    Gaudreault, Mathieu; Drolet, François; Viñals, Jorge

    2010-11-01

    Analytical expressions for pitchfork and Hopf bifurcation thresholds are given for a nonlinear stochastic differential delay equation with feedback. Our results assume that the delay time τ is small compared to other characteristic time scales, not a significant limitation close to the bifurcation line. A pitchfork bifurcation line is found, the location of which depends on the conditional average , where x(t) is the dynamical variable. This conditional probability incorporates the combined effect of fluctuation correlations and delayed feedback. We also find a Hopf bifurcation line which is obtained by a multiple scale expansion around the oscillatory solution near threshold. We solve the Fokker-Planck equation associated with the slowly varying amplitudes and use it to determine the threshold location. In both cases, the predicted bifurcation lines are in excellent agreement with a direct numerical integration of the governing equations. Contrary to the known case involving no delayed feedback, we show that the stochastic bifurcation lines are shifted relative to the deterministic limit and hence that the interaction between fluctuation correlations and delay affect the stability of the solutions of the model equation studied.

  13. Minimum Delay Moving Object Detection

    KAUST Repository

    Lao, Dong

    2017-11-09

    We present a general framework and method for detection of an object in a video based on apparent motion. The object moves relative to background motion at some unknown time in the video, and the goal is to detect and segment the object as soon it moves in an online manner. Due to unreliability of motion between frames, more than two frames are needed to reliably detect the object. Our method is designed to detect the object(s) with minimum delay, i.e., frames after the object moves, constraining the false alarms. Experiments on a new extensive dataset for moving object detection show that our method achieves less delay for all false alarm constraints than existing state-of-the-art.

  14. Depressive illness delayed Hamlet's revenge.

    Science.gov (United States)

    Shaw, A B; Pickering, Neil

    2002-12-01

    If Hamlet had not delayed his revenge there would have been no play. Many explanations of the delay have been offered in the last four centuries. None is convincing. The interpretation which best fits the evidence best is that Hamlet was suffering from an acute depressive illness, with some obsessional features. He could not make a firm resolve to act. In Shakespeare's time there was no concept of acute depressive illness, although melancholy was well known. Melancholy, however, would have been seen as a character defect. In the tragic model the hero brings himself and others to ruin because of a character defect. Thus, at the time, the play conformed to the tragic model. With today's knowledge, it does not. This analysis adds to, but does not replace, other insights into the play.

  15. Air congestion delay: a review

    Directory of Open Access Journals (Sweden)

    Daniel Alberto Pamplona

    2016-04-01

    Full Text Available This article is a literature review of the air congestion delay and its costs. Air congestion is a worldwide problem. Its existence brings costs for airlines and discomfort for passengers. With the increasing demand for air transport, the study of air congestion has attracted the attention of many researchers around the world. The cause for the delays is erroneously attributed only to the lack of infrastructure investments. The literature review shows that other factors such as population growth, increasing standards of living, lack of operational planning and environmental issues exercise decisive influence. Several studies have been conducted in order to analyze and propose solutions to this problem that affects society as a whole.

  16. Minimum Delay Moving Object Detection

    KAUST Repository

    Lao, Dong

    2017-01-08

    We present a general framework and method for detection of an object in a video based on apparent motion. The object moves relative to background motion at some unknown time in the video, and the goal is to detect and segment the object as soon it moves in an online manner. Due to unreliability of motion between frames, more than two frames are needed to reliably detect the object. Our method is designed to detect the object(s) with minimum delay, i.e., frames after the object moves, constraining the false alarms. Experiments on a new extensive dataset for moving object detection show that our method achieves less delay for all false alarm constraints than existing state-of-the-art.

  17. Minimum Delay Moving Object Detection

    KAUST Repository

    Lao, Dong; Sundaramoorthi, Ganesh

    2017-01-01

    We present a general framework and method for detection of an object in a video based on apparent motion. The object moves relative to background motion at some unknown time in the video, and the goal is to detect and segment the object as soon it moves in an online manner. Due to unreliability of motion between frames, more than two frames are needed to reliably detect the object. Our method is designed to detect the object(s) with minimum delay, i.e., frames after the object moves, constraining the false alarms. Experiments on a new extensive dataset for moving object detection show that our method achieves less delay for all false alarm constraints than existing state-of-the-art.

  18. Teriparatide Induced Delayed Persistent Hypercalcemia

    Directory of Open Access Journals (Sweden)

    Nirosshan Thiruchelvam

    2014-01-01

    Full Text Available Teriparatide, a recombinant PTH, is an anabolic treatment for osteoporosis that increases bone density. Transient hypercalcemia is a reported side effect of teriparatide that is seen few hours following administration of teriparatide and resolves usually within 16 hours of drug administration. Persistent hypercalcemia, although not observed in clinical trials, is rarely reported. The current case describes a rare complication of teriparatide induced delayed persistent hypercalcemia.

  19. Minimum Delay Moving Object Detection

    KAUST Repository

    Lao, Dong

    2017-05-14

    This thesis presents a general framework and method for detection of an object in a video based on apparent motion. The object moves, at some unknown time, differently than the “background” motion, which can be induced from camera motion. The goal of proposed method is to detect and segment the object as soon it moves in an online manner. Since motion estimation can be unreliable between frames, more than two frames are needed to reliably detect the object. Observing more frames before declaring a detection may lead to a more accurate detection and segmentation, since more motion may be observed leading to a stronger motion cue. However, this leads to greater delay. The proposed method is designed to detect the object(s) with minimum delay, i.e., frames after the object moves, constraining the false alarms, defined as declarations of detection before the object moves or incorrect or inaccurate segmentation at the detection time. Experiments on a new extensive dataset for moving object detection show that our method achieves less delay for all false alarm constraints than existing state-of-the-art.

  20. Development of delayed radiation necrosis

    International Nuclear Information System (INIS)

    Ohara, ShigFeki; Takagi, Terumasa; Shibata, Taichiro; Nagai, Hajime.

    1983-01-01

    The authors discussed the developing process of delayed radiation necrosis of the brain from the case of a 42-year-old female who developed intracranial hypertension and left hemiparesis 5 and a half years after radiotherapy for pituitary adenoma. The initial sign of radiation necrosis was from a CT scan taken 3 and a half years after radiotherapy showing an irregular low density lesion in the right temporal lobe. CT scan 2 years later demonstrated displacement of the midline structures to the left and a larger low density lesion with partially high density in the right MCA territory that was enhanced with intravenous contrast medium. Recovery after a right temporal lobectomy and administration of steroid hormone were uneventful. Eight months later there were no signs of raised intracranial pressure nor of neurological deficits. Tissues obtained from the right temporal lobe at lobectomy revealed the characteristic changes of delayed radiation necrosis; a mixture of fresh, recent, and old vascular lesions in the same specimen. From these findings, it was speculated that delayed radiation necrosis might initially occur within several years after radiotherapy and might gradually take a progressive and extended course, even in cases whose clinical symptoms develop much later. (author)

  1. Radiation cell survival and growth delay studies in multicellular spheroids of small-cell lung carcinoma

    International Nuclear Information System (INIS)

    Duchesne, G.M.; Peacock, J.H.

    1987-01-01

    The radiation sensitivity of two small-cell lung carcinoma cell lines growing as multicellular spheroids in static culture was determined using clonogenic cell survival and growth delay as endpoints. Growth delay determination suggested that clonogenic cell kill was less than was obtained by direct assay of cell survival. Recovery from potentially lethal damage was assayed in one line (HC12) but was not demonstrable, and clonogenic cell survival decreased with time in treated spheroids with diameters greater than 300 μm which contained a hypoxic cell population. Microscopic examination of the treated spheroids showed the emergence of an abnormal giant-cell population, and the progressive clonogenic cell loss that occurred after treatment was thought to be due to oxygen and nutrient deprivation of the remaining viable cells by this doomed cell population. Correction of the growth delay measurements for changes in cell size and clonogenic cell population allowed correlation of the growth delay and cell survival data. (author)

  2. Synchronization in networks with heterogeneous coupling delays

    Science.gov (United States)

    Otto, Andreas; Radons, Günter; Bachrathy, Dániel; Orosz, Gábor

    2018-01-01

    Synchronization in networks of identical oscillators with heterogeneous coupling delays is studied. A decomposition of the network dynamics is obtained by block diagonalizing a newly introduced adjacency lag operator which contains the topology of the network as well as the corresponding coupling delays. This generalizes the master stability function approach, which was developed for homogenous delays. As a result the network dynamics can be analyzed by delay differential equations with distributed delay, where different delay distributions emerge for different network modes. Frequency domain methods are used for the stability analysis of synchronized equilibria and synchronized periodic orbits. As an example, the synchronization behavior in a system of delay-coupled Hodgkin-Huxley neurons is investigated. It is shown that the parameter regions where synchronized periodic spiking is unstable expand when increasing the delay heterogeneity.

  3. Mittag-Leffler Stability Theorem for Fractional Nonlinear Systems with Delay

    Directory of Open Access Journals (Sweden)

    S. J. Sadati

    2010-01-01

    Full Text Available Fractional calculus started to play an important role for analysis of the evolution of the nonlinear dynamical systems which are important in various branches of science and engineering. In this line of taught in this paper we studied the stability of fractional order nonlinear time-delay systems for Caputo's derivative, and we proved two theorems for Mittag-Leffler stability of the fractional nonlinear time delay systems.

  4. Synchronization analysis of coloured delayed networks under ...

    Indian Academy of Sciences (India)

    This paper investigates synchronization of coloured delayed networks under decentralized pinning intermittent control. To begin with, the time delays are taken into account in the coloured networks. In addition, we propose a decentralized pinning intermittent control for coloured delayed networks, which is different from that ...

  5. Adaptation to delayed force perturbations in reaching movements.

    Directory of Open Access Journals (Sweden)

    Noa Levy

    Full Text Available Adaptation to deterministic force perturbations during reaching movements was extensively studied in the last few decades. Here, we use this methodology to explore the ability of the brain to adapt to a delayed velocity-dependent force field. Two groups of subjects preformed a standard reaching experiment under a velocity dependent force field. The force was either immediately proportional to the current velocity (Control or lagged it by 50 ms (Test. The results demonstrate clear adaptation to the delayed force perturbations. Deviations from a straight line during catch trials were shifted in time compared to post-adaptation to a non-delayed velocity dependent field (Control, indicating expectation to the delayed force field. Adaptation to force fields is considered to be a process in which the motor system predicts the forces to be expected based on the state that a limb will assume in response to motor commands. This study demonstrates for the first time that the temporal window of this prediction needs not to be fixed. This is relevant to the ability of the adaptive mechanisms to compensate for variability in the transmission of information across the sensory-motor system.

  6. Carry-chain propagation delay impacts on resolution of FPGA-based TDC

    International Nuclear Information System (INIS)

    Dong Lei; Yang Junfeng; Song Kezhu

    2014-01-01

    The architecture of carry chains in Field-Programmable Gate Array (FPGA) is introduced in this paper. The propagation delay time of the rising and falling edges in the carry chains are calculated according to the architecture and they are predicted not equal in most cases. Tests show that the measuring results of the propagation delay time in EP3C120F484C8N series FPGA of Altera are in line with the inference. The difference of propagation delay time results in different accuracies of Time-to-Digital Converter (TDC). This phenomenon shall be considered in the design of TDC implemented in FPGA. It can ensure better accuracy. (authors)

  7. Delay Variation Model with Two Service Queues

    Directory of Open Access Journals (Sweden)

    Filip Rezac

    2010-01-01

    Full Text Available Delay in VoIP technology is very unpleasant issue and therefore a voice packets prioritization must be ensured. To maintain the high call quality a maximum information delivery time from the sender to the recipient is set to 150 ms. This paper focuses on the design of a mathematical model of end-to-end delay of a VoIP connection, in particular on a delay variation. It describes all partial delay components and mechanisms, their generation, facilities and mathematical formulations. A new approach to the delay variation model is presented and its validation has been done by experimention.

  8. Fuzzy delay model based fault simulator for crosstalk delay fault test ...

    Indian Academy of Sciences (India)

    In this paper, a fuzzy delay model based crosstalk delay fault simulator is proposed. As design trends move towards nanometer technologies, more number of new parameters affects the delay of the component. Fuzzy delay models are ideal for modelling the uncertainty found in the design and manufacturing steps.

  9. Precise delay measurement through combinatorial logic

    Science.gov (United States)

    Burke, Gary R. (Inventor); Chen, Yuan (Inventor); Sheldon, Douglas J. (Inventor)

    2010-01-01

    A high resolution circuit and method for facilitating precise measurement of on-chip delays for FPGAs for reliability studies. The circuit embeds a pulse generator on an FPGA chip having one or more groups of LUTS (the "LUT delay chain"), also on-chip. The circuit also embeds a pulse width measurement circuit on-chip, and measures the duration of the generated pulse through the delay chain. The pulse width of the output pulse represents the delay through the delay chain without any I/O delay. The pulse width measurement circuit uses an additional asynchronous clock autonomous from the main clock and the FPGA propagation delay can be displayed on a hex display continuously for testing purposes.

  10. Reasons for diagnostic delay in gynecological malignancies

    DEFF Research Database (Denmark)

    Vandborg, Mai Partridge; Christensen, René dePont Christensen; Kragstrup, Jakob

    2011-01-01

    (≤ or > 60 years), performance of gynecological examination by the GP and notification of cancer suspicion on first referral from GP’s on the diagnostic delay (short delay ≤90 days and long delay >90 days). Results Across cancer type a median total delay of 101 days was observed. The 10% of women......Aim The primary aim of this study was to identify and describe different delay types in women with gynecologic cancer, and to analyze the relationship between diagnostic delay and a number of characteristics for patients, cancers and the health care system. Setting A cohort study of women newly......) and The Danish Gynecological Cancer Database (DGCD). 161 women were included; ovarian cancer: 63, endometrial cancer: 50, cervical cancer: 34 and vulvar cancer: 14. Outcome measures were different delay types counted in days and the influence of four clinical important variables: Presence of alarm symptoms, age...

  11. Temperature Dependent Wire Delay Estimation in Floorplanning

    DEFF Research Database (Denmark)

    Winther, Andreas Thor; Liu, Wei; Nannarelli, Alberto

    2011-01-01

    Due to large variations in temperature in VLSI circuits and the linear relationship between metal resistance and temperature, the delay through wires of the same length can be different. Traditional thermal aware floorplanning algorithms use wirelength to estimate delay and routability. In this w......Due to large variations in temperature in VLSI circuits and the linear relationship between metal resistance and temperature, the delay through wires of the same length can be different. Traditional thermal aware floorplanning algorithms use wirelength to estimate delay and routability....... In this work, we show that using wirelength as the evaluation metric does not always produce a floorplan with the shortest delay. We propose a temperature dependent wire delay estimation method for thermal aware floorplanning algorithms, which takes into account the thermal effect on wire delay. The experiment...

  12. Elite athletes and pubertal delay.

    Science.gov (United States)

    Kapczuk, Karina

    2017-10-01

    Intensive physical training and participation in competitive sports during childhood and early adolescence may affect athletes' pubertal development. On the other hand, pubertal timing, early or late, may impact on an athlete selection for a particular sport. Genetic predisposition, training load, nutritional status and psychological stress determine athletes' pubertal timing. Athletes that practice esthetic sports, especially gymnasts, are predisposed to a delay in pubertal development. The growing evidence indicates that energy deficiency, not a systemic training per se, plays a crucial role in the pathogenesis of functional hypothalamic hypogonadism in female athletes. Metabolic and psychologic stress activate hypothalamic-pituitary-adrenal axis and suppress hypothalamic-pituitary-ovarian axis. Female athletes who do not begin secondary sexual development by the age of 14 or menstruation by the age of 16 warrant a comprehensive evaluation and a targeted treatment. Somatic growth and sexual maturation of elite female athletes are largely sport-specific since each sport favors a particular somatotype and requires a specific training. Chronic negative energy balance resulting from a systemic physical training and inadequate energy intake may delay pubertal development in elite athletes. Youth athletes, especially those engaged in competitive sports that emphasize prepubertal or lean appearance, are at risk of developing relative energy deficiency in sport associated with disordered eating or eating disorders. Management strategies should address the complex conditions underlying functional hypothalamic hypogonadism.

  13. Delayed recombination and cosmic parameters

    International Nuclear Information System (INIS)

    Galli, Silvia; Melchiorri, Alessandro; Bean, Rachel; Silk, Joseph

    2008-01-01

    Current cosmological constraints from cosmic microwave background anisotropies are typically derived assuming a standard recombination scheme, however additional resonance and ionizing radiation sources can delay recombination, altering the cosmic ionization history and the cosmological inferences drawn from the cosmic microwave background data. We show that for recent observations of the cosmic microwave background anisotropy, from the Wilkinson microwave anisotropy probe satellite mission (WMAP) 5-year survey and from the arcminute cosmology bolometer array receiver experiment, additional resonance radiation is nearly degenerate with variations in the spectral index, n s , and has a marked effect on uncertainties in constraints on the Hubble constant, age of the universe, curvature and the upper bound on the neutrino mass. When a modified recombination scheme is considered, the redshift of recombination is constrained to z * =1078±11, with uncertainties in the measurement weaker by 1 order of magnitude than those obtained under the assumption of standard recombination while constraints on the shift parameter are shifted by 1σ to R=1.734±0.028. From the WMAP5 data we obtain the following constraints on the resonance and ionization sources parameters: ε α i <0.058 at 95% c.l.. Although delayed recombination limits the precision of parameter estimation from the WMAP satellite, we demonstrate that this should not be the case for future, smaller angular scales measurements, such as those by the Planck satellite mission.

  14. Asymptotic Delay Analysis for Cross-Layer Delay-Based Routing in Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Philippe Jacquet

    2007-01-01

    Full Text Available This paper addresses the problem of the evaluation of the delay distribution via analytical means in IEEE 802.11 wireless ad hoc networks. We show that the asymptotic delay distribution can be expressed as a power law. Based on the latter result, we present a cross-layer delay estimation protocol and we derive new delay-distribution-based routing algorithms, which are well adapted to the QoS requirements of real-time multimedia applications. In fact, multimedia services are not sensitive to average delays, but rather to the asymptotic delay distributions. Indeed, video streaming applications drop frames when they are received beyond a delay threshold, determined by the buffer size. Although delay-distribution-based routing is an NP-hard problem, we show that it can be solved in polynomial time when the delay threshold is large, because of the asymptotic power law distribution of the link delays.

  15. Ogura-CMS in Chinese cabbage (Brassica rapa ssp. pekinensis) causes delayed expression of many nuclear genes.

    Science.gov (United States)

    Dong, Xiangshu; Kim, Wan Kyu; Lim, Yong-Pyo; Kim, Yeon-Ki; Hur, Yoonkang

    2013-02-01

    We investigated the mechanism regulating cytoplasmic male sterility (CMS) in Brassica rapa ssp. pekinensis using floral bud transcriptome analyses of Ogura-CMS Chinese cabbage and its maintainer line in B. rapa 300-K oligomeric probe (Br300K) microarrays. Ogura-CMS Chinese cabbage produced few and infertile pollen grains on indehiscent anthers. Compared to the maintainer line, CMS plants had shorter filaments and plant growth, and delayed flowering and pollen development. In microarray analysis, 4646 genes showed different expression, depending on floral bud size, between Ogura-CMS and its maintainer line. We found 108 and 62 genes specifically expressed in Ogura-CMS and its maintainer line, respectively. Ogura-CMS line-specific genes included stress-related, redox-related, and B. rapa novel genes. In the maintainer line, genes related to pollen coat and germination were specifically expressed in floral buds longer than 3mm, suggesting insufficient expression of these genes in Ogura-CMS is directly related to dysfunctional pollen. In addition, many nuclear genes associated with auxin response, ATP synthesis, pollen development and stress response had delayed expression in Ogura-CMS plants compared to the maintainer line, which is consistent with the delay in growth and development of Ogura-CMS plants. Delayed expression may reduce pollen grain production and/or cause sterility, implying that mitochondrial, retrograde signaling delays nuclear gene expression. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  16. Mode Selection Rule for Three-Delay Systems

    Science.gov (United States)

    Takahashi, Kin'ya; Kobayashi, Taizo

    2017-12-01

    We study the mode selection rule for a three-delay system to determine which oscillation mode is first excited by the Hopf bifurcation with increasing control parameter. We use linear stability analysis to detect an oscillating mode excited by the first bifurcation. There are two conditions, relevant and irrelevant conditions, determined by the ratios of three delay times, t1, t2, and tf, where tf is fixed and t1 and t2 are set as 0 < t1 < tf and 0 < t2 < tf. In a neighborhood of the relevant condition defined such that both t1/tf = n1/m1 and t2/tf = n2/m2 are ratios of odd to odd, oscillations nearly equal to the \\tilde{m}th-harmonic mode are excited, where \\tilde{m} is the least common multiple of m1 and m2. In the parameter space (t1,t2), there are irrelevant lines each of which is determined by a rational dependence of t1, t2, and tf, and does not allow any relevant condition. Extremely high order modes are observed along both sides of the irrelevant line. In particular, the line t2 = tf - t1, i.e., a diagonal with a slope of -1, shows the strongest irrelevancy.

  17. Stabilization of the Propagation Delay in Fiber Optics in a Frequency Distribution Link Using Electronic Delay Lines: First Measurement Results

    Science.gov (United States)

    2010-11-01

    of Time and Frequency ul. Elektoralna 2, 00-139 Warszawa , Poland Tel: +48 22 5819156, E-mail: timegum@gum.gov.pl Łukasz Śliwczyński, Przemysław...Elektoralna 2, 00-139 Warszawa , Poland 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S

  18. The TCD50 and regrowth delay assay in human tumor xenografts: Differences and implications

    International Nuclear Information System (INIS)

    Budach, W.; Budach, V.; Stuschke, M.; Dinges, S.; Sack, H.

    1993-01-01

    The response to irradiation of five human xenograft cell lines - a malignant paraganglioma, a neurogenic sarcoma, a malignant histiocytoma, a primary lymphoma of the brain, and a squamous cell carcinoma - were tested in nude mice. All mice underwent 5 Gy whole body irradiation prior to xenotransplantation to minimize the residual immune response. The subcutaneous tumors were irradiated at a tumor volume of 120 mm 3 under acutely hypoxic conditions with single doses between 8 Gy and 80 Gy depending on the expected radiation sensitivity of the tumor line. Endpoints of the study were the tumor control dose 50% (TCD 50 ) and the regrowth delay endpoints growth delay, specific growth delay, and the tumor bed effect corrected specific growth delay. Specific growth delay and corrected specific growth delay at 76% of the TCD 50 was used in order to compare the data to previously published data from spheroids. The lowest TCD 50 was found in the lymphoma with 24.9 Gy, whereas the TCD 50 of the soft tissue sarcomas and the squamous cell carcinoma ranged from 57.8 Gy to 65.6 Gy. The isoeffective dose levels for the induction of 30 days growth delay, a specific growth delay of 3, and a corrected specific growth delay of 3 ranged from 15.5 Gy (ECL1) to 37.1 Gy (FADU), from 7.2 Gy (ENE2) to 45.6 Gy (EPG1) and from 9.2 Gy (ENE2) to 37.6 Gy (EPG1), respectively. The corrected specific growth delay at 76% of the TCD 50 was correlated with the number of tumor rescue units per 100 cells in spheroids, which was available for three tumor lines, and with the tumor doubling time in xenografts (n = 5). The TCD 50 values corresponded better to the clinical experience than the regrowth delay data. There was no correlation between TCD 50 and any of the regrowth delay endpoints. This missing correlation was most likely a result of large differences in the number of tumor rescue units in human xenografts of the same size

  19. Cable line engineering

    International Nuclear Information System (INIS)

    Jang, Hak Sin; Kim, Sin Yeong

    1998-02-01

    This book is about cable line engineering. It is comprised of nine chapters, which deals with summary of cable communication such as way, process of cable communication and optical communication, Line constant of transmission on primary constant, reflection and crosstalk, communication cable line of types like flat cable, coaxial cable and loaded cable, Install of communication line with types and facility of aerial line, construction method of communication line facility, Measurement of communication line, Carrier communication of summary, PCM communication with Introduction, regeneration relay system sampling and quantization and Electric communication service and general information network with mobile communication technique and satellite communication system.

  20. Dynamics of Nonlinear Time-Delay Systems

    CERN Document Server

    Lakshmanan, Muthusamy

    2010-01-01

    Synchronization of chaotic systems, a patently nonlinear phenomenon, has emerged as a highly active interdisciplinary research topic at the interface of physics, biology, applied mathematics and engineering sciences. In this connection, time-delay systems described by delay differential equations have developed as particularly suitable tools for modeling specific dynamical systems. Indeed, time-delay is ubiquitous in many physical systems, for example due to finite switching speeds of amplifiers in electronic circuits, finite lengths of vehicles in traffic flows, finite signal propagation times in biological networks and circuits, and quite generally whenever memory effects are relevant. This monograph presents the basics of chaotic time-delay systems and their synchronization with an emphasis on the effects of time-delay feedback which give rise to new collective dynamics. Special attention is devoted to scalar chaotic/hyperchaotic time-delay systems, and some higher order models, occurring in different bran...

  1. Group Delay of High Q Antennas

    DEFF Research Database (Denmark)

    Bahramzy, Pevand; Pedersen, Gert Frølund

    2013-01-01

    Group Delay variations versus frequency is an essential factor which can cause distortion and degradation in the signals. Usually this is an issue in wideband communication systems, such as satellite communication systems, which are used for transmitting wideband data. However, group delay can also...... become an issue, when working with high Q antennas, because of the steep phase shift over the frequency. In this paper, it is measured how large group delay variations can become, when going from a low Q antenna to a high Q antenna. The group delay of a low Q antenna is shown to be around 1.3 ns, whereas...... a high Q antenna has group delay of around 22 ns. It is due to this huge group delay variation characteristics of high Q antennas, that signal distortion might occur in the radio system with high Q antennas....

  2. Permutation entropy with vector embedding delays

    Science.gov (United States)

    Little, Douglas J.; Kane, Deb M.

    2017-12-01

    Permutation entropy (PE) is a statistic used widely for the detection of structure within a time series. Embedding delay times at which the PE is reduced are characteristic timescales for which such structure exists. Here, a generalized scheme is investigated where embedding delays are represented by vectors rather than scalars, permitting PE to be calculated over a (D -1 ) -dimensional space, where D is the embedding dimension. This scheme is applied to numerically generated noise, sine wave and logistic map series, and experimental data sets taken from a vertical-cavity surface emitting laser exhibiting temporally localized pulse structures within the round-trip time of the laser cavity. Results are visualized as PE maps as a function of embedding delay, with low PE values indicating combinations of embedding delays where correlation structure is present. It is demonstrated that vector embedding delays enable identification of structure that is ambiguous or masked, when the embedding delay is constrained to scalar form.

  3. Delays in the management of retroperitoneal sarcomas

    DEFF Research Database (Denmark)

    Seinen, Jojanneke; Almquist, Martin; Styring, Emelie

    2010-01-01

    Retroperitoneal sarcomas are rare and treatment should optimally be centralized. Despite successful centralization with 90% of the patients referred prior to surgery, delays occur, which led us to assess lead times in a population-based series. Method. Patients diagnosed with retroperitoneal...... sarcoma in the southern Sweden health care region 2003-2009 were eligible for the study. Data on referrals and diagnostic investigations were collected from clinical files from primary health care, local hospitals, and from the sarcoma centre. Lead times were divided into patient delays and health care...... delays caused by primary health care, local hospitals, or procedures at the sarcoma centre. Results. Complete data were available from 33 patients and demonstrated a median patient delay of 23¿days (0-17¿months) and median health care delay of 94¿days (1-40¿months) with delays of median 15¿days...

  4. Time Delay Estimation Algoritms for Echo Cancellation

    Directory of Open Access Journals (Sweden)

    Kirill Sakhnov

    2011-01-01

    Full Text Available The following case study describes how to eliminate echo in a VoIP network using delay estimation algorithms. It is known that echo with long transmission delays becomes more noticeable to users. Thus, time delay estimation, as a part of echo cancellation, is an important topic during transmission of voice signals over packetswitching telecommunication systems. An echo delay problem associated with IP-based transport networks is discussed in the following text. The paper introduces the comparative study of time delay estimation algorithm, used for estimation of the true time delay between two speech signals. Experimental results of MATLab simulations that describe the performance of several methods based on cross-correlation, normalized crosscorrelation and generalized cross-correlation are also presented in the paper.

  5. CGI delay compensation. [Computer Generated Image

    Science.gov (United States)

    Mcfarland, R. E.

    1986-01-01

    Computer-generated graphics in real-time helicopter simulation produces objectionable scene-presentation time delays. In the flight simulation laboratory at Ames Research Center, it has been determined that these delays have an adverse influence on pilot performance during agressive tasks such as nap of the earth (NOE) maneuvers. Using contemporary equipment, computer generated image (CGI) time delays are an unavoidable consequence of the operations required for scene generation. However, providing that magnitude distortions at higher frequencies are tolerable, delay compensation is possible over a restricted frequency range. This range, assumed to have an upper limit of perhaps 10 or 15 rad/sec, conforms approximately to the bandwidth associated with helicopter handling qualities research. A compensation algorithm is introduced here and evaluated in terms of tradeoffs in frequency responses. The algorithm has a discrete basis and accommodates both a large, constant transport delay interval and a periodic delay interval, as associated with asynchronous operations.

  6. Memorized discrete systems and time-delay

    CERN Document Server

    Luo, Albert C J

    2017-01-01

    This book examines discrete dynamical systems with memory—nonlinear systems that exist extensively in biological organisms and financial and economic organizations, and time-delay systems that can be discretized into the memorized, discrete dynamical systems. It book further discusses stability and bifurcations of time-delay dynamical systems that can be investigated through memorized dynamical systems as well as bifurcations of memorized nonlinear dynamical systems, discretization methods of time-delay systems, and periodic motions to chaos in nonlinear time-delay systems. The book helps readers find analytical solutions of MDS, change traditional perturbation analysis in time-delay systems, detect motion complexity and singularity in MDS; and determine stability, bifurcation, and chaos in any time-delay system.

  7. Does Bilingualism Delay the Development of Dementia?

    OpenAIRE

    Amy L Atkinson

    2016-01-01

    It has been suggested that bilingualism (where individuals speak two languages) may delay the development of dementia. However, much of the research is inconclusive. Some researchers have reported that bilingualism delays the onset and diagnosis of dementia, whilst other studies have found weak or even detrimental effects. This paper reviews a series of nine empirical studies, published up until March 2016, which investigated whether bilingualism significantly delays the onset of dementia. Th...

  8. Delayed enhanced MRI in intraparenchymal tumors

    International Nuclear Information System (INIS)

    Eguchi, Takahiko; Morimoto, Tetsuya; Takeshima, Toshikazu

    1991-01-01

    Delayed enhanced MRI was performed on 20 intraparenchymal tumors, and these findings were compared with those of early enhanced MRI. Using the spin-echo technique (SE: 400-500/20 msec), early scans were obtained 5 minutes, and delayed scans were obtained 60 minutes, after the intravenous injection of 0.1 nmol of gadolinium-DTPA/Kg. We discussed the changes in the delayed scan with regard to the change in the pattern of enhancement and the boundary of enhancement. In these twenty intraparenchymal tumors, there were three low-grade astrocytomas, two anaplastic astrocytomas, seven glioblastomas, and eight metastatic tumors. The changes in the enhanced pattern showed three types as follows: Type I: heterogeneous enhancement in both early and delayed scans; Type II: heterogeneous enhancement in early scan and homogeneous enhancement in delayed scan; Type III: homogeneous enhancement in both early and delayed scans. Most malignant tumors, such as glioblastomas (6/8), anaplastic astrocytomas (2/2), and metastatic tumors (7/8), revealed Type I, although low-grade astrocytomas showed Type II (3/2) and Type III (1/3). The heterogeneous enhancement in delayed scan was found in malignant tumors and in low-grade astrocytoma; even if the early scan revealed heterogeneous enhancement, the delayed scan showed homogeneous enhancement. In the delayed scan, most enhanced boundaries spread out of the boundaries in the early scan. Glioblastomas spread markedly in the delayed scan, although none of the low-grade astrocytomas, anaplastic astrocytomas, or metastases revealed marked spreading. We called these marked increases in the delayed scan a 'spreading sign' and thought that this sign was specific to glioblastomas. Recently some authors have emphasized the usefulness of serial scans. Delayed enhanced MRI 60 minutes after the administration of a contrast medium was here found also to be useful for the accurate diagnosis for brain tumors. (author)

  9. Relationships between processing delay and microbial load of broiler neck skin samples.

    Science.gov (United States)

    Lucianez, A; Holmes, M A; Tucker, A W

    2010-01-01

    The measurable microbial load on poultry carcasses during processing is determined by a number of factors including farm or origin, processing hygiene, and external temperature. This study investigated associations between carcass microbial load and progressive delays to processing. A total of 30 carcasses were delayed immediately after defeathering and before evisceration in a commercial abattoir in groups of five, and were held at ambient temperature for 1, 2, 3, 4, 6, and 8 h. Delayed carcasses were reintroduced to the processing line, and quantitative assessment of total viable count, coliforms, Staphylococcus aureus, and Pseudomonas spp. was undertaken on neck skin flap samples collected after carcass chilling and then pooled for each group. Sampling was repeated on 5 separate days, and the data were combined. Significant increases in total viable count (P = 0.001) and coliforms (P = 0.004), but not for S. aureus or Pseudomonas loads, were observed across the 8-h period of delay. In line with previous studies, there was significant variation in microbiological data according to sampling day. In conclusion, there is a significant and measurable decline in microbiological status of uneviscerated but defeathered poultry carcasses after an 8-h delay, but the variability of sampling results, reflecting the wide range of factors that impact microbial load, means that it is not possible to determine maximum or minimum acceptable periods of processing delay based on this criterion alone.

  10. Neutron stochastic transport theory with delayed neutrons

    International Nuclear Information System (INIS)

    Munoz-Cobo, J.L.; Verdu, G.

    1987-01-01

    From the stochastic transport theory with delayed neutrons, the Boltzmann transport equation with delayed neutrons for the average flux emerges in a natural way without recourse to any approximation. From this theory a general expression is obtained for the Feynman Y-function when delayed neutrons are included. The single mode approximation for the particular case of a subcritical assembly is developed, and it is shown that Y-function reduces to the familiar expression quoted in many books, when delayed neutrons are not considered, and spatial and source effects are not included. (author)

  11. Effect of applied voltage and inter-pulse delay in spark-assisted LIBS

    Science.gov (United States)

    Robledo-Martinez, A.; Sobral, H.; Garcia-Villarreal, A.

    2018-06-01

    We report the results obtained in an investigation on the effect of the time delay between the laser and electrical pulses in a spark-assisted laser-induced breakdown spectroscopy (LIBS) experiment. The electrical discharge is produced by the discharge of a charged coaxial cable. This arrangement produces a fast unipolar current pulse (500 ns) that applies high power ( 600 kW) to the laser ablation plasma. The delay between the laser pulse and the electric pulse can be controlled at will in order to find the optimal time in terms of enhancement of the emitted lines. It was found that the application of the high voltage pulse enhances the ionic lines emitted by up to two orders of magnitude. An additional enhancement by a factor of 2-4 can be obtained delaying the application of the electric pulse by a time of 0.6-20 μs. In the tests it was noticed that the ionic lines were found to be clearly responsive to increments in the applied electric energy while the neutral lines did so marginally. Our results show that the intensification of the lines is mainly due to reheating of the ablation plasma as the application of the electrical pulse increments the temperature of the ablation plasma by about 50%. It is demonstrated that the present technique is an efficient way of intensifying the lines emitted without incurring in additional damage to the sample.

  12. Delayed habituation in Behcet's disease.

    Science.gov (United States)

    Gulturk, Sefa; Akyol, Melih; Kececi, Hulusi; Ozcelik, Sedat; Cinar, Ziynet; Demirkazik, Ayse

    2008-01-01

    The autonomic nervous system in Behcet's patients may be affected due to various reasons. This entity may be detected with the measurement of the electrodermal activities, heart rate variability and pupillometric methods. Habituation is one of the implicit forms of learning and memory and the loss of habituation can reveal pathological changes in the synaptic regions. To determine whether there is a functional decrease in the synaptic effectiveness (habituation) of the pathways to sympathetic neurons that had been repeatedly activated in Behcet's. Twelve patients with Behcet's disease and 12 healthy controls were included in the study. Sympathetic skin potential (SSP) records were taken at normal room temperature in a quiet place within a Faraday cage. Sixteen square wave single shock impulses (duration: 1200 ms, strength: 5 mA) were applied on each case. After the 1st stimulus, the SSP amplitudes were lower in the patients compared to the controls (P0.05). Whereas there was no significant differences among the SSP amplitudes after the 9th impulse in the controls (P>0.05). The habituation rate of the SSP after consecutive impulses was slowest in the patients compared to controls (P<0.001, t value=12.39). There is a delayed habituation in Behcet's disease and that may due to pathologic changes with vasculitis through their peripheral nerves.

  13. Analysis Of Primary Coolant Suction Side Pressure In The Delay Chamber Of The RSG-GAS

    International Nuclear Information System (INIS)

    Dibyo, Sukmanto

    2000-01-01

    Delay chamber is a tank to delay flow that located in the primary cooling suction side of RSG-GAS. A void occurred when operation reactor caused by too high the delta P at inlet suction pump. The condition may be avoided by using one line mode of the cooling flow. The analysis show that void volume in the delay chamber is occurred because the coolant negative pressure lowers the saturation pressure should be avoided though decreasing the delta P until about 0.1 bar at about 45 exp 0 C. Solution suggested are to use bypass flow from the spent fuel to the delay chamber. Coolant temperature can be also decreased by decreasing the power level of the reactor as well as improving the heat exchanger and cooling tower performances

  14. Feedforward Delay Estimators in Adverse Multipath Propagation for Galileo and Modernized GPS Signals

    Directory of Open Access Journals (Sweden)

    Lohan Elena Simona

    2006-01-01

    Full Text Available The estimation with high accuracy of the line-of-sight delay is a prerequisite for all global navigation satellite systems. The delay locked loops and their enhanced variants are the structures of choice for the commercial GNSS receivers, but their performance in severe multipath scenarios is still rather limited. The new satellite positioning system proposals specify higher code-epoch lengths compared to the traditional GPS signal and the use of a new modulation, the binary offset carrier (BOC modulation, which triggers new challenges in the delay tracking stage. We propose and analyze here the use of feedforward delay estimation techniques in order to improve the accuracy of the delay estimation in severe multipath scenarios. First, we give an extensive review of feedforward delay estimation techniques for CDMA signals in fading channels, by taking into account the impact of BOC modulation. Second, we extend the techniques previously proposed by the authors in the context of wideband CDMA delay estimation (e.g., Teager-Kaiser and the projection onto convex sets to the BOC-modulated signals. These techniques are presented as possible alternatives to the feedback tracking loops. A particular attention is on the scenarios with closely spaced paths. We also discuss how these feedforward techniques can be implemented via DSPs.

  15. Time delays, population, and economic development

    Science.gov (United States)

    Gori, Luca; Guerrini, Luca; Sodini, Mauro

    2018-05-01

    This research develops an augmented Solow model with population dynamics and time delays. The model produces either a single stationary state or multiple stationary states (able to characterise different development regimes). The existence of time delays may cause persistent fluctuations in both economic and demographic variables. In addition, the work identifies in a simple way the reasons why economics affects demographics and vice versa.

  16. On Delay and Security in Network Coding

    Science.gov (United States)

    Dikaliotis, Theodoros K.

    2013-01-01

    In this thesis, delay and security issues in network coding are considered. First, we study the delay incurred in the transmission of a fixed number of packets through acyclic networks comprised of erasure links. The two transmission schemes studied are routing with hop-by-hop retransmissions, where every node in the network simply stores and…

  17. Delaying Developmental Mathematics: The Characteristics and Costs

    Science.gov (United States)

    Johnson, Marianne; Kuennen, Eric

    2004-01-01

    This paper investigates which students delay taking a required developmental mathematics course and the impact of delay on student performance in introductory microeconomics. Analysis of a sample of 1462 students at a large Midwestern university revealed that, although developmental-level mathematics students did not reach the same level of…

  18. ANALYSING SURFACE MOVEMENT DELAYS IN AN AIRPORT

    Directory of Open Access Journals (Sweden)

    Volodymyr Kharchenko

    2014-07-01

    Full Text Available Queuing effect can be in the different components of ground operations. Causes of surface – movement delays are long taxi – in and taxi – out operations during departure and arrival of aircraft. Surface movement delays in an airport are analyzed

  19. Analyzing delay causes in Egyptian construction projects

    Directory of Open Access Journals (Sweden)

    Mohamed M. Marzouk

    2014-01-01

    Full Text Available Construction delays are common problems in civil engineering projects in Egypt. These problems occur frequently during project life-time leading to disputes and litigation. Therefore, it is essential to study and analyze causes of construction delays. This research presents a list of construction delay causes retrieved from literature. The feedback of construction experts was obtained through interviews. Subsequently, a questionnaire survey was prepared. The questionnaire survey was distributed to thirty-three construction experts who represent owners, consultants, and contractor’s organizations. Frequency Index, Severity Index, and Importance Index are calculated and according to the highest values of them the top ten delay causes of construction projects in Egypt are determined. A case study is analyzed and compared to the most important delay causes in the research. Statistical analysis is carried out using analysis of variance ANOVA method to test delay causes, obtained from the survey. The test results reveal good correlation between groups while there is significant difference between them for some delay causes and finally roadmap for prioritizing delay causes groups is presented.

  20. Algebraic entropy for differential-delay equations

    OpenAIRE

    Viallet, Claude M.

    2014-01-01

    We extend the definition of algebraic entropy to a class of differential-delay equations. The vanishing of the entropy, as a structural property of an equation, signals its integrability. We suggest a simple way to produce differential-delay equations with vanishing entropy from known integrable differential-difference equations.

  1. Test Anxiety and Academic Delay of Gratification

    Science.gov (United States)

    Bembenutty, Hefer

    2009-01-01

    The present study examined the relationship between college students' willingness to delay gratification, motivation, self-regulation of learning, and their level of test anxiety (N = 364). Academic delay of gratification refers to students' postponement of immediately available opportunities to satisfy impulses in favor of pursuing academic…

  2. Delaying gratification depends on social trust

    Science.gov (United States)

    Michaelson, Laura; de la Vega, Alejandro; Chatham, Christopher H.; Munakata, Yuko

    2013-01-01

    Delaying gratification is hard, yet predictive of important life outcomes, such as academic achievement and physical health. Prominent theories focus on the role of self-control, hypersensitivity to immediate rewards, and the cost of time spent waiting. However, delaying gratification may also require trust in people delivering future rewards as promised. To test the role of social trust, participants were presented with character vignettes and faces that varied in trustworthiness, and then choose between hypothetical smaller immediate or larger delayed rewards from those characters. Across two experiments, participants were less willing to wait for delayed rewards from less trustworthy characters, and perceived trustworthiness predicted willingness to delay gratification. These findings provide the first demonstration of a causal role for social trust in willingness to delay gratification, independent of other relevant factors, such as self-control or reward history. Thus, delaying gratification requires choosing not only a later reward, but a reward that is potentially less likely to be delivered, when there is doubt about the person promising it. Implications of this work include the need to revise prominent theories of delay of gratification, and new directions for interventions with populations characterized by impulsivity. PMID:23801977

  3. Delaying gratification depends on social trust

    Directory of Open Access Journals (Sweden)

    Laura eMichaelson

    2013-06-01

    Full Text Available Delaying gratification is hard, yet predictive of important life outcomes, such as academic achievement and physical health. Prominent theories focus on the role of self-control, hypersensitivity to immediate rewards, and the cost of time spent waiting. However, delaying gratification may also require trust in people delivering future rewards as promised. To test the role of social trust, participants were presented with character vignettes and faces that varied in trustworthiness, and then chose between hypothetical smaller immediate or larger delayed rewards from those characters. Across two experiments, participants were less willing to wait for delayed rewards from less trustworthy characters, and perceived trustworthiness predicted willingness to delay gratification. These findings provide the first demonstration of a causal role for social trust in willingness to delay gratification, independent of other relevant factors, such as self-control or reward history. Thus, delaying gratification requires choosing not only a later reward, but a reward that is potentially less likely to be delivered, when there is doubt about the person promising it. Implications of this work include the need to revise prominent theories of delay of gratification, and new directions for interventions with populations characterized by impulsivity.

  4. Beta delayed particle emission in light nuclei

    International Nuclear Information System (INIS)

    Riisager, K.; Gabelmann, H.

    1991-01-01

    A short discussion of theoretical treatments of beta delayed particle emission is followed by a presentation of data on the newly found beta delayed deuteron decay of 6 He. This decay cannot be described properly with existing theories. (author) 8 refs.; 3 figs

  5. Allee effects on population dynamics with delay

    International Nuclear Information System (INIS)

    Celik, C.; Merdan, H.; Duman, O.; Akin, O.

    2008-01-01

    In this paper, we study the stability analysis of equilibrium points of population dynamics with delay when the Allee effect occurs at low population density. Mainly, our mathematical results and numerical simulations point to the stabilizing effect of the Allee effects on population dynamics with delay

  6. Nonlinear delay monopoly with bounded rationality

    International Nuclear Information System (INIS)

    Matsumoto, Akio; Szidarovszky, Ferenc

    2012-01-01

    The purpose of this paper is to study the dynamics of a monopolistic firm in a continuous-time framework. The firm is assumed to be boundedly rational and to experience time delays in obtaining and implementing information on output. The dynamic adjustment process is based on the gradient of the expected profit. The paper is divided into three parts: we examine delay effects on dynamics caused by one-time delay and two-time delays in the first two parts. Global dynamics and analytical results on local dynamics are numerically confirmed in the third part. Four main results are demonstrated. First, the stability switch from stability to instability occurs only once in the case of a single delay. Second, the alternation of stability and instability can continue if two time delays are involved. Third, the occurence of Hopf bifurcation is analytically shown if stability is lost. Finally, in a bifurcation process, there are a period-doubling cascade to chaos and a period-halving cascade to the equilibrium point in the case of two time delays if the difference between the two delays is large.

  7. Environmental impact of high voltage aerial transmission lines

    International Nuclear Information System (INIS)

    Silva, R.P.; Mouallen, M.C.; Quintella, S.E.A.

    1989-01-01

    The identification of environmental impacts caused by the aerial transmission lines and the measures for reducing these impacts are discussed, considering the impact over the soil in different areas, biological effects caused by delayed exposure and visual impacts due to the line structures. A methodology for the impact evaluation and the aspects of the Environmental Impact Studies and Environmental Impact Report are also studied. (C.G.C.). 2 refs, 1 fig

  8. VT Electric Transmission Line Corridors - corridor lines

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The ELTRN layer depicts electric transmission line corridors in Vermont. Various methods have been used to digitize features. The data layer...

  9. Fuzzy delay model based fault simulator for crosstalk delay fault test ...

    Indian Academy of Sciences (India)

    In this paper, a fuzzy delay model based crosstalk delay fault simulator is proposed. As design .... To find the quality of non-robust tests, a fuzzy delay ..... Dubois D and Prade H 1989 Processing Fuzzy temporal knowledge. IEEE Transactions ...

  10. Delay-dependent exponential stability of cellular neural networks with time-varying delays

    International Nuclear Information System (INIS)

    Zhang Qiang; Wei Xiaopeng; Xu Jin

    2005-01-01

    The global exponential stability of cellular neural networks (CNNs) with time-varying delays is analyzed. Two new sufficient conditions ensuring global exponential stability for delayed CNNs are obtained. The conditions presented here are related to the size of delay. The stability results improve the earlier publications. Two examples are given to demonstrate the effectiveness of the obtained results

  11. Synchronization of delayed systems in the presence of delay time modulation

    International Nuclear Information System (INIS)

    Kye, Won-Ho; Choi, Muhan; Kim, Myung-Woon; Lee, Soo-Young; Rim, Sunghwan; Kim, Chil-Min; Park, Young-Jai

    2004-01-01

    We investigate synchronization in the presence of delay time modulation for application to communication. We have observed that the robust synchronization is established by a common delay signal and its threshold is presented using Lyapunov exponents analysis. The influence of the delay time modulation in chaotic oscillators is also discussed

  12. Gravitational Lens Time Delays Using Polarization Monitoring

    Directory of Open Access Journals (Sweden)

    Andrew Biggs

    2017-11-01

    Full Text Available Gravitational lens time delays provide a means of measuring the expansion of the Universe at high redshift (and therefore in the ‘Hubble flow’ that is independent of local calibrations. It was hoped that many of the radio lenses found in the JVAS/CLASS survey would yield time delays as these were selected to have flat spectra and are dominated by multiple compact components. However, despite extensive monitoring with the Very Large Array (VLA, time delays have only been measured for three of these systems (out of 22. We have begun a programme to reanalyse the existing VLA monitoring data with the goal of producing light curves in polarized flux and polarization position angle, either to improve delay measurements or to find delays for new sources. Here, we present preliminary results on the lens system B1600+434 which demonstrate the presence of correlated and substantial polarization variability in each image.

  13. Controllability of nonlinear delay oscillating systems

    Directory of Open Access Journals (Sweden)

    Chengbin Liang

    2017-05-01

    Full Text Available In this paper, we study the controllability of a system governed by second order delay differential equations. We introduce a delay Gramian matrix involving the delayed matrix sine, which is used to establish sufficient and necessary conditions of controllability for the linear problem. In addition, we also construct a specific control function for controllability. For the nonlinear problem, we construct a control function and transfer the controllability problem to a fixed point problem for a suitable operator. We give a sufficient condition to guarantee the nonlinear delay system is controllable. Two examples are given to illustrate our theoretical results by calculating a specific control function and inverse of a delay Gramian matrix.

  14. Dynamics of microbubble oscillators with delay coupling

    Science.gov (United States)

    Heckman, C. R.; Sah, S. M.; Rand, R. H.

    2010-10-01

    We investigate the stability of the in-phase mode in a system of two delay-coupled bubble oscillators. The bubble oscillator model is based on a 1956 paper by Keller and Kolodner. Delay coupling is due to the time it takes for a signal to travel from one bubble to another through the liquid medium that surrounds them. Using techniques from the theory of differential-delay equations as well as perturbation theory, we show that the equilibrium of the in-phase mode can be made unstable if the delay is long enough and if the coupling strength is large enough, resulting in a Hopf bifurcation. We then employ Lindstedt's method to compute the amplitude of the limit cycle as a function of the time delay. This work is motivated by medical applications involving noninvasive localized drug delivery via microbubbles.

  15. Homotopic Polygonal Line Simplification

    DEFF Research Database (Denmark)

    Deleuran, Lasse Kosetski

    This thesis presents three contributions to the area of polygonal line simplification, or simply line simplification. A polygonal path, or simply a path is a list of points with line segments between the points. A path can be simplified by morphing it in order to minimize some objective function...

  16. Microscopic Control Delay Modeling at Signalized Arterials Using Bluetooth Technology

    OpenAIRE

    Rajasekhar, Lakshmi

    2011-01-01

    Real-time control delay estimation is an important performance measure for any intersection to improve the signal timing plans dynamically in real-time and hence improve the overall system performance. Control delay estimates helps to determine the level-of-service (LOS) characteristics of various approaches at an intersection and takes into account deceleration delay, stopped delay and acceleration delay. All kinds of traffic delay calculation especially control delay calculation has always ...

  17. On the cost/delay tradeoff of wireless delay tolerant geographic routing

    OpenAIRE

    Tasiopoulos, Argyrios; Tsiaras, Christos; Toumpis, Stavros

    2012-01-01

    In Delay Tolerant Networks (DTNs), there is a fundamental tradeoff between the aggregate transport cost of a packet and the delay in its delivery. We study this tradeoff in the context of geographical routing in wireless DTNs.We ?rst specify the optimal cost/delay tradeoff, i.e., the tradeoff under optimal network operation, using a dynamic network construction termed the Cost/Delay Evolving Graph (C/DEG) and the Optimal Cost/Delay Curve (OC/DC), a function that gives the minimum possible agg...

  18. A new electrostatic on-line collection-system

    International Nuclear Information System (INIS)

    Dufour, J.P.; Del Moral, R.; Fleury, A.; Hubert, F.; Llabador, Y.; Mauhourat, M.B.; Bimbot, R.; Gardes, D.; Rivet, M.F.

    1981-01-01

    The working conditions of a new on-line electrostatic collection system are presented. The main characteristics are high efficiency (reaching 20%) and short delay time (down to the millisecond). The salient features of specific devices for measurements of absolute cross sections, recoil range distributions and angular distributions are given. (orig.)

  19. Specialization processes in on-line unsupervised learning

    NARCIS (Netherlands)

    Biehl, M.; Freking, A.; Reents, G.; Schlösser, E.

    1998-01-01

    From the recent analysis of supervised learning by on-line gradient descent in multilayered neural networks it is known that the necessary process of student specialization can be delayed significantly. We demonstrate that this phenomenon also occurs in various models of unsupervised learning. A

  20. Effect of Different Structure Type Traffic On Railway Line Capacity

    Directory of Open Access Journals (Sweden)

    Gleba Radosław

    2017-04-01

    Full Text Available The article points to methods of analyzing railway traffic conditions based on two parameters: capacity and delay of trains. The impact of the differentiated railway type structure on the capacity of the railway line was presented. Particular attention has been paid to the assessment of commonly used simplifications in analyzes.

  1. A new electrostatic on-line collection-system

    International Nuclear Information System (INIS)

    Dufour, J.P.; Del Moral, R.; Fleury, A.

    1981-06-01

    The working conditions of a new on-line electrostatic collection system are presented. The main charactersitics are high efficiency (reaching 20%) and short delay time (down to the millisecond). The salient features of specific devices for measurements of absolute cross sections, recoil range distributions and angular distributions are given

  2. Micro-simulation based analysis of railway lines robustness

    DEFF Research Database (Denmark)

    Cerreto, Fabrizio

    2015-01-01

    train course that can represent the total train delay along the line. Dispatching measures in case of disturbance are excluded by applying First-In First-Out rule in simulations. The benefits of modifications to the track infrastructure, the timetable, and the signaling system, in terms of consecutive...

  3. Numerical modelling of multimode fibre-optic communication lines

    Energy Technology Data Exchange (ETDEWEB)

    Sidelnikov, O S; Fedoruk, M P [Novosibirsk State University, Novosibirsk (Russian Federation); Sygletos, S; Ferreira, F [Aston University, England, Birmingham, B4 7ET (United Kingdom)

    2016-01-31

    The results of numerical modelling of nonlinear propagation of an optical signal in multimode fibres with a small differential group delay are presented. It is found that the dependence of the error vector magnitude (EVM) on the differential group delay can be reduced by increasing the number of ADC samples per symbol in the numerical implementation of the differential group delay compensation algorithm in the receiver. The possibility of using multimode fibres with a small differential group delay for data transmission in modern digital communication systems is demonstrated. It is shown that with increasing number of modes the strong coupling regime provides a lower EVM level than the weak coupling one. (fibre-optic communication lines)

  4. Reward acts as a signal to control delay-period activity in delayed-response tasks.

    Science.gov (United States)

    Ichihara-Takeda, Satoe; Takeda, Kazuyoshi; Funahashi, Shintaro

    2010-03-31

    Prefrontal delay-period activity represents a neural mechanism for the active maintenance of information and needs to be controlled by some signal to appropriately operate working memory. To examine whether reward-delivery acts as this signal, the effects of delay-period activity in response to unexpected reward-delivery were examined by analyzing single-neuron activity recorded in the primate dorsolateral prefrontal cortex. Among neurons that showed delay-period activity, 34% showed inhibition of this activity in response to unexpected reward-delivery. The delay-period activity of these neurons was affected by the expectation of reward-delivery. The strength of the reward signal in controlling the delay-period activity is related to the strength of the effect of reward information on the delay-period activity. These results indicate that reward-delivery acts as a signal to control delay-period activity.

  5. Chaos synchronization in time-delayed systems with parameter mismatches and variable delay times

    International Nuclear Information System (INIS)

    Shahverdiev, E.M.; Nuriev, R.A.; Hashimov, R.H.; Shore, K.A.

    2004-06-01

    We investigate synchronization between two undirectionally linearly coupled chaotic nonidentical time-delayed systems and show that parameter mismatches are of crucial importance to achieve synchronization. We establish that independent of the relation between the delay time in the coupled systems and the coupling delay time, only retarded synchronization with the coupling delay time is obtained. We show that with parameter mismatch or without it neither complete nor anticipating synchronization occurs. We derive existence and stability conditions for the retarded synchronization manifold. We demonstrate our approach using examples of the Ikeda and Mackey Glass models. Also for the first time we investigate chaos synchronization in time-delayed systems with variable delay time and find both existence and sufficient stability conditions for the retarded synchronization manifold with the coupling-delay lag time. (author)

  6. Spectrum optimization-based chaotification using time-delay feedback control

    International Nuclear Information System (INIS)

    Zhou Jiaxi; Xu Daolin; Zhang Jing; Liu Chunrong

    2012-01-01

    Highlights: ► A time-delay feedback controller is designed for chaotification. ► A spectrum optimization method is proposed to determine chaotification parameters. ► Numerical examples verify the spectrum optimization- based chaotification method. ► Engineering application in line spectrum reconfiguration is demonstrated. - Abstract: In this paper, a spectrum optimization method is developed for chaotification in conjunction with an application in line spectrum reconfiguration. A key performance index (the objective function) based on Fourier spectrum is specially devised with the idea of suppressing spectrum spikes and broadening frequency band. Minimization of the index empowered by a genetic algorithm enables to locate favorable parameters of the time-delay feedback controller, by which a line spectrum of harmonic vibration can be transformed into a broad-band continuous spectrum of chaotic motion. Numerical simulations are carried out to verify the feasibility of the method and to demonstrate its effectiveness of chaotifying a 2-DOFs linear mechanical system.

  7. Delays in Building Construction Projects in Ghana

    Directory of Open Access Journals (Sweden)

    Adwoa B Agyakwah-Baah

    2010-07-01

    Full Text Available This study investigates the causes of delay of building construction projects in Ghana to determine the most important according to the key project participants; clients, consultants, and contractors. Thirty-two possible causes of delay were identified from the literature and semi-structured interviews of 15 key players in the implementation process. These delay factors were further categorised into nine major groups. The list of delay causes was subjected to a questionnaire survey for the identification of the most important causes of delay. The field survey included 130 respondents made up of 39 contractors, 37 clients and 54 consultants. The relative importance of the individual causes and the groups were calculated and ranked by their relative importance index. The overall results of the study indicate that the respondents generally agree that financial group factors ranked highest among the major factors causing delay in construction projects in Ghana. The financial group factors were delay in honouring payment certificates, difficulty in accessing credit and fluctuation in prices. Materials group factors are second followed by scheduling and controlling factors.

  8. Behavioral effects of delayed timeouts from reinforcement.

    Science.gov (United States)

    Byrne, Tom; Poling, Alan

    2017-03-01

    Timeouts are sometimes used in applied settings to reduce target responses, and in some circumstances delays are unavoidably imposed between the onset of a timeout and the offset of the response that produces it. The present study examined the effects of signaled and unsignaled timeouts in rats exposed to concurrent fixed-ratio 1 fixed-ratio 1 schedules of food delivery, where each response on one lever, the location of which changed across conditions, produced both food and a delayed 10-s timeout. Delays of 0 to 38 s were examined. Delayed timeouts often, but not always, substantially reduced the number of responses emitted on the lever that produced timeouts relative to the number emitted on the lever that did not produce timeouts. In general, greater sensitivity was observed to delayed timeouts when they were signaled. These results demonstrate that delayed timeouts, like other delayed consequences, can affect behavior, albeit less strongly than immediate consequences. © 2017 Society for the Experimental Analysis of Behavior.

  9. Representing delayed force feedback as a combination of current and delayed states.

    Science.gov (United States)

    Avraham, Guy; Mawase, Firas; Karniel, Amir; Shmuelof, Lior; Donchin, Opher; Mussa-Ivaldi, Ferdinando A; Nisky, Ilana

    2017-10-01

    To adapt to deterministic force perturbations that depend on the current state of the hand, internal representations are formed to capture the relationships between forces experienced and motion. However, information from multiple modalities travels at different rates, resulting in intermodal delays that require compensation for these internal representations to develop. To understand how these delays are represented by the brain, we presented participants with delayed velocity-dependent force fields, i.e., forces that depend on hand velocity either 70 or 100 ms beforehand. We probed the internal representation of these delayed forces by examining the forces the participants applied to cope with the perturbations. The findings showed that for both delayed forces, the best model of internal representation consisted of a delayed velocity and current position and velocity. We show that participants relied initially on the current state, but with adaptation, the contribution of the delayed representation to adaptation increased. After adaptation, when the participants were asked to make movements with a higher velocity for which they had not previously experienced with the delayed force field, they applied forces that were consistent with current position and velocity as well as delayed velocity representations. This suggests that the sensorimotor system represents delayed force feedback using current and delayed state information and that it uses this representation when generalizing to faster movements. NEW & NOTEWORTHY The brain compensates for forces in the body and the environment to control movements, but it is unclear how it does so given the inherent delays in information transmission and processing. We examined how participants cope with delayed forces that depend on their arm velocity 70 or 100 ms beforehand. After adaptation, participants applied opposing forces that revealed a partially correct representation of the perturbation using the current and the

  10. Transmission delays in hardware clock synchronization

    Science.gov (United States)

    Shin, Kang G.; Ramanathan, P.

    1988-01-01

    Various methods, both with software and hardware, have been proposed to synchronize a set of physical clocks in a system. Software methods are very flexible and economical but suffer an excessive time overhead, whereas hardware methods require no time overhead but are unable to handle transmission delays in clock signals. The effects of nonzero transmission delays in synchronization have been studied extensively in the communication area in the absence of malicious or Byzantine faults. The authors show that it is easy to incorporate the ideas from the communication area into the existing hardware clock synchronization algorithms to take into account the presence of both malicious faults and nonzero transmission delays.

  11. A continuous time Cournot duopoly with delays

    International Nuclear Information System (INIS)

    Gori, Luca; Guerrini, Luca; Sodini, Mauro

    2015-01-01

    This paper extends the classical repeated duopoly model with quantity-setting firms of Bischi et al. (1998) by assuming that production of goods is subject to some gestation lags but exchanges take place continuously in the market. The model is expressed in the form of differential equations with discrete delays. By using some recent mathematical techniques and numerical experiments, results show some dynamic phenomena that cannot be observed when delays are absent. In addition, depending on the extent of time delays and inertia, synchronisation failure can arise even in the event of homogeneous firms.

  12. Delayed encephalopathy after acute carbon monoxide poisoning

    Directory of Open Access Journals (Sweden)

    Mehmet İbrahim Turan

    2014-03-01

    Full Text Available Carbon monoxide poisoning is a major cause of death following attempted suicide and accidental exposures. Although clinical presentation depends on the duration and the intensity of exposure, the assessment of the severity of intoxication is difficult. A small percentage of patients who show complete initial recovery may develop delayed neurological deficits. Delayed encephalopathy after acute carbon monoxide poisoning is a rare and poor prognosis neurologic disorders and there is no specific treatment. We present a case with early onset of delayed encephalopathy after acute carbon monoxide poisoning with typical cranial imaging findings in a child with atypical history and clinical presentation.

  13. Bubbling in delay-coupled lasers.

    Science.gov (United States)

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

    2009-06-01

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

  14. Travelling wave solutions in delayed cooperative systems

    International Nuclear Information System (INIS)

    Li, Bingtuan; Zhang, Liang

    2011-01-01

    We establish the existence of travelling wave solutions for delayed cooperative recursions that are allowed to have more than two equilibria. We define an important extended real number that is used to determine the speeds of travelling wave solutions. The results can be applied to a large class of delayed cooperative reaction–diffusion models. We show that for a delayed Lotka–Volterra reaction–diffusion competition model, there exists a finite positive number c * + that can be characterized as the slowest speed of travelling wave solutions connecting two mono-culture equilibria or connecting a mono-culture with the coexistence equilibrium

  15. Transcriptional delay stabilizes bistable gene networks.

    Science.gov (United States)

    Gupta, Chinmaya; López, José Manuel; Ott, William; Josić, Krešimir; Bennett, Matthew R

    2013-08-02

    Transcriptional delay can significantly impact the dynamics of gene networks. Here we examine how such delay affects bistable systems. We investigate several stochastic models of bistable gene networks and find that increasing delay dramatically increases the mean residence times near stable states. To explain this, we introduce a non-Markovian, analytically tractable reduced model. The model shows that stabilization is the consequence of an increased number of failed transitions between stable states. Each of the bistable systems that we simulate behaves in this manner.

  16. End-to-End Delay Model for Train Messaging over Public Land Mobile Networks

    Directory of Open Access Journals (Sweden)

    Franco Mazzenga

    2017-11-01

    Full Text Available Modern train control systems rely on a dedicated radio network for train to ground communications. A number of possible alternatives have been analysed to adopt the European Rail Traffic Management System/European Train Control System (ERTMS/ETCS control system on local/regional lines to improve transport capacity. Among them, a communication system based on public networks (cellular&satellite provides an interesting, effective and alternative solution to proprietary and expensive radio networks. To analyse performance of this solution, it is necessary to model the end-to-end delay and message loss to fully characterize the message transfer process from train to ground and vice versa. Starting from the results of a railway test campaign over a 300 km railway line for a cumulative 12,000 traveled km in 21 days, in this paper, we derive a statistical model for the end-to-end delay required for delivering messages. In particular, we propose a two states model allowing for reproducing the main behavioral characteristics of the end-to-end delay as observed experimentally. Model formulation has been derived after deep analysis of the recorded experimental data. When it is applied to model a realistic scenario, it allows for explicitly accounting for radio coverage characteristics, the received power level, the handover points along the line and for the serving radio technology. As an example, the proposed model is used to generate the end-to-end delay profile in a realistic scenario.

  17. The recommendation of line-balancing improvement on MCM product line 1 using genetics algorithm and moodie young at XYZ Company, Co.

    Science.gov (United States)

    Sriwana, I. K.; Marie, I. A.; Mangala, D.

    2017-12-01

    Kencana Gemilang, Co. is one electronics industry engaging in the manufacture sector. This company manufactures and assembles household electronic products, such as rice cooker, fan, iron, blender, etc. The company deals with an issue of underachievement of an established production target on MCM products line 1. This study aimed to calculate line efficiencies, delay times, and initial line smoothness indexes. The research was carried out by means of depicting a precedence diagram and gathering time data of each work element followed by examination and calculation of standard time as well as line balancing using methods of Moodie Young and Generics Algorithm. Based on results of calculation, better line balancing than the existing initial conditions, i.e. improvement in the line efficiency by 18.39%, deterioration in balanced delay by 28.39%, and deterioration of a smoothness index by 23.85% was obtained.

  18. OSCILLATION OF NONLINEAR DELAY DIFFERENCE EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper deals with the oscillatory properties of a class of nonlinear difference equations with several delays. Sufficient criteria in the form of infinite sum for the equations to be oscillatory are obtained.

  19. Compensating for telecommunication delays during robotic telerehabilitation.

    Science.gov (United States)

    Consoni, Leonardo J; Siqueira, Adriano A G; Krebs, Hermano I

    2017-07-01

    Rehabilitation robotic systems may afford better care and telerehabilitation may extend the use and benefits of robotic therapy to the home. Data transmissions over distance are bound by intrinsic communication delays which can be significant enough to deem the activity unfeasible. Here we describe an approach that combines unilateral robotic telerehabilitation and serious games. This approach has a modular and distributed design that permits different types of robots to interact without substantial code changes. We demonstrate the approach through an online multiplayer game. Two users can remotely interact with each other with no force exchanges, while a smoothing and prediction algorithm compensates motions for the delay in the Internet connection. We demonstrate that this approach can successfully compensate for data transmission delays, even when testing between the United States and Brazil. This paper presents the initial experimental results, which highlight the performance degradation with increasing delays as well as improvements provided by the proposed algorithm, and discusses planned future developments.

  20. Isolation Effect in Immediate and Delayed Recall

    Science.gov (United States)

    Bellezza, Francis S.; Cheney, Terry L.

    1973-01-01

    If the hypothesis of selective rehearsal is used to account for the isolation effect, then the recall of isolated items will depend both on the serial position of the isolated item and on whether recall is immediate or delayed. (Author)

  1. A simple chaotic delay differential equation

    International Nuclear Information System (INIS)

    Sprott, J.C.

    2007-01-01

    The simplest chaotic delay differential equation with a sinusoidal nonlinearity is described, including the route to chaos, Lyapunov exponent spectrum, and chaotic diffusion. It is prototypical of many other high-dimensional chaotic systems

  2. Time delay of quantum scattering processes

    International Nuclear Information System (INIS)

    Martin, P.A.

    1981-01-01

    The author presents various aspects of the theory of the time delay of scattering processes. The author mainly studies non-relativistic two-body scattering processes, first summarizing briefly the theory of simple scattering systems. (Auth.)

  3. Does Bilingualism Delay the Development of Dementia?

    Directory of Open Access Journals (Sweden)

    Amy L Atkinson

    2016-08-01

    Full Text Available It has been suggested that bilingualism (where individuals speak two languages may delay the development of dementia. However, much of the research is inconclusive. Some researchers have reported that bilingualism delays the onset and diagnosis of dementia, whilst other studies have found weak or even detrimental effects. This paper reviews a series of nine empirical studies, published up until March 2016, which investigated whether bilingualism significantly delays the onset of dementia. The article also explores whether the inconsistent findings can be attributed to differences in study designs or the definitions of bilingualism used between studies. Based on current evidence, it appears that lifelong bilingualism, where individuals frequently use both languages, may be protective against dementia. However, becoming bilingual in adulthood or using the second language infrequently is unlikely to substantially delay onset of the disease.

  4. Rich dynamics of discrete delay ecological models

    International Nuclear Information System (INIS)

    Peng Mingshu

    2005-01-01

    We study multiple bifurcations and chaotic behavior of a discrete delay ecological model. New form of chaos for the 2-D map is observed: the combination of potential period doubling and reverse period-doubling leads to cascading bubbles

  5. Four-channel delay generator model 5740

    International Nuclear Information System (INIS)

    Baumatz, D.; Milner, M.

    1978-01-01

    The 4-channel delay generator model 5740 generates 4-pulse groups in independent channels. The device offers the possibility of controlling both the time intervals between the pulses of a group and the rate of generation of groups

  6. Lauch of CERN particle accelerator delayed

    CERN Multimedia

    2007-01-01

    "Scientists seeking to uncover the secrets of the universe will have to wait a little longer after the CERN laboratory inSwitzerland yesterday confirmed a delay in tests of its massive new particle accelerator." (1 page)

  7. Diagnosis delay in tuberculosis and its consequences

    International Nuclear Information System (INIS)

    Habibullah, S.; Sheikh, M.A.; Sadiq, A.; Anwar, T.

    2004-01-01

    Objective: To find out the average duration from onset of symptoms to the diagnosis and treatment of tuberculosis, reasons for diagnostic delay, its consequences, association of variables and formulation of recommendations. Results: In this study it was found that average time from onset of initial symptoms to diagnosis and treatment of tuberculosis was 120 days. In 64% of the patients medical practitioners were responsible for delaying the diagnosis of tuberculosis. Loss of weight in 40% and haemoptysis is 21% were the consequences of diagnostic delay of tuberculosis. Delay in the diagnosis of tuberculosis was statistically significant in those patients who consulted private practitioners, and consequences of tuberculosis were severe in those patients who consulted late. (author)

  8. Variable Delay in port-Hamiltonian Telemanipulation

    NARCIS (Netherlands)

    Secchi, C; Stramigioli, Stefano; Fantuzzi, C.

    2006-01-01

    In several applications involving bilateral telemanipulation, master and slave act at different power scales. In this paper a strategy for passively dealing with variable communication delay in scaled port-Hamiltonian based telemanipulation over packet switched networks is proposed.

  9. High voltage transmission lines - what are the hazards

    International Nuclear Information System (INIS)

    Repacholi, M.H.

    1985-01-01

    With the increasing use of high voltage alternating current (HVAC) transmission lines there is a growing concern among the public about possible human health effects resulting from exposure to the electric fields associated with these lines. While there is no definitive evidence of such effects, mounting public fear and activism over hypothesized health risks is already causing delays in the licensing and constuction of major power transmission facilities, and is encouraging the formation of regulatory policy. This paper briefly reviews the concerns, biological effects data and standards for HVAC transmission lines

  10. Directed line liquids

    International Nuclear Information System (INIS)

    Kamien, R.D.

    1992-01-01

    This thesis is devoted to the study of ensembles of dense directed lines. These lines are principally to be thought of as polymers, though they also have the morphology of flux lines in high temperature superconductors, strings of colloidal spheres in electrorheological fluids and the world lines of quantum mechanical bosons. The authors discuss how directed polymer melts, string-like formations in electrorheological and ferro-fluids, flux lines in high temperature superconductors and the world lines of quantum mechanical bosons all share similar descriptions. They study a continuous transition in all of these systems, and then study the critical mixing properties of binary mixtures of directed polymers through the renormalization group. They predict the exponents for a directed polymer blend consolute point and a novel two-phase superfluid liquid-gas critical point

  11. Nonlinear Cournot duopoly with implementation delays

    International Nuclear Information System (INIS)

    Matsumoto, Akio; Szidarovszky, Ferenc

    2015-01-01

    We study the effects of two delays on the local as well as on global stability of nonlinear Cournot duopoly dynamics. The two major findings are an analytical construction of the stability switching curve on which stability is lost and the numerical confirmation of the birth of aperiodic global dynamics when the stationary state is locally unstable. The delays matters and can generate various dynamics ranging from simple to complicated dynamics.

  12. Delay in polling systems in heavy traffic

    Science.gov (United States)

    van der Mei, Robert D.

    1998-10-01

    We study the delay in asymmetric cyclic polling systems with general mixtures of gated and exhaustive service, with generally distributed service times and switch-over times, in heavy traffic. We obtain closed-form expressions for all moments of the delay incurred at each of the queues. The expressions are strikingly simple and can even be expressed as finite products of known factors. The results provide new insights into the heavy-traffic behavior of polling systems.

  13. Acceptable Channel Switching Delays for Mobile TV

    DEFF Research Database (Denmark)

    Fleury, Alexandre; Pedersen, Jakob Schou; Larsen, Lars Bo

    2011-01-01

    as well as three potential effect factors: the transition type, the test environment and the audiovisual content. The results show that delays longer than 5.7 seconds annoyed test participants, and that the transition type had a significant impact on the rating of channel switching delays. However......, neither the test environment nor the audiovisual content influenced the ratings significantly. Finally, a discussion of these results and directions for future research are proposed....

  14. Inverse Problems for Nonlinear Delay Systems

    Science.gov (United States)

    2011-03-15

    population dynamics. We consider the delay between birth and adulthood for neonate pea aphids and present a mathematical model that treats this delay as...which there is currently no known cure. For HIV, the core of the virus is composed of single-stranded viral RNA and protein components. As depicted in...at a CD4 receptor site and the viral core is injected into the cell. Once inside, the protein components enable transcription and integration of the

  15. The Strategic Perils of Delayed Differentiation

    OpenAIRE

    Krishnan S. Anand; Karan Girotra

    2007-01-01

    The value of delayed differentiation (also known as postponement) for a monopolist has been extensively studied in the operations literature. We analyze the case of (imperfectly) competitive markets with demand uncertainty, wherein the choice of supply chain configuration (i.e., early or delayed differentiation) is endogenous to the competing firms. We characterize firms' choices in equilibrium and analyze the effects of these choices on quantities sold, profits, consumer surplus, and welfare...

  16. Diagnosis delay in Libyan female breast cancer

    Directory of Open Access Journals (Sweden)

    Ermiah Eramah

    2012-08-01

    Full Text Available Abstract Aims To study the diagnosis delay and its impact on stage of disease among women with breast cancer on Libya. Methods 200 women, aged 22 to 75 years with breast cancer diagnosed during 2008–2009 were interviewed about the period from the first symptoms to the final histological diagnosis of breast cancer. This period (diagnosis time was categorized into 3 periods: 6 months. If diagnosis time was longer than 3 months, the diagnosis was considered delayed (diagnosis delay. Consultation time was the time taken to visit the general practitioner after the first symptoms. Retrospective preclinical and clinical data were collected on a form (questionnaire during an interview with each patient and from medical records. Results The median of diagnosis time was 7.5 months. Only 30.0% of patients were diagnosed within 3 months after symptoms. 14% of patients were diagnosed within 3–6 months and 56% within a period longer than 6 months. A number of factors predicted diagnosis delay: Symptoms were not considered serious in 27% of patients. Alternative therapy (therapy not associated with cancer was applied in 13.0% of the patients. Fear and shame prevented the visit to the doctor in 10% and 4.5% of patients, respectively. Inappropriate reassurance that the lump was benign was an important reason for prolongation of the diagnosis time. Diagnosis delay was associated with initial breast symptom(s that did not include a lump (p  Diagnosis delay was associated with bigger tumour size (p Conclusions Diagnosis delay is very serious problem in Libya. Diagnosis delay was associated with complex interactions between several factors and with advanced stages. There is a need for improving breast cancer awareness and training of general practitioners to reduce breast cancer mortality by promoting early detection. The treatment guidelines should pay more attention to the early phases of breast cancer. Especially, guidelines for good practices in managing

  17. Time delay in a multichannel formalism

    International Nuclear Information System (INIS)

    Haberzettl, Helmut; Workman, Ron

    2007-01-01

    We reexamine the time-delay formalism of Wigner, Eisenbud, and Smith, which was developed to analyze both elastic and inelastic resonances. An error in the paper of Smith has propagated through the literature. We correct this error and show how the results of Eisenbud and Smith are related. We also comment on some recent time-delay studies, based on Smith's erroneous interpretation of the Eisenbud result

  18. Tunability of the FBG group delay through acousto-optic modulation

    Science.gov (United States)

    Marques, Carlos A. F.; Oliveira, Roberson A.; Pohl, Alexandre A. P.; Nogueira, Rogério N.

    2013-03-01

    A new method for fine control of the group delay of a fiber Bragg grating (FBG) is presented. It is based on an acoustic wave applied to the fiber. The standing acoustic wave imposes a periodic chirp to the uniform FBG. Tunability is obtained through adjustment of the intensity and/or frequency of the acoustic wave. A fast switching time of ∼17 μs was achieved. The experimental results were verified by theoretical simulation showing a good agreement between them. It can be used for different applications such as tunable narrow dispersion compensator for independent coarse wavelength division multiplexing (CWDM) channels or optical delay lines.

  19. Series Transmission Line Transformer

    Science.gov (United States)

    Buckles, Robert A.; Booth, Rex; Yen, Boris T.

    2004-06-29

    A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

  20. Corporate Attributes and Audit Delay in Emerging Markets: Empirical Evidence from Nigeria

    Directory of Open Access Journals (Sweden)

    Afensimi Elijah

    2015-03-01

    Full Text Available The broad objective of the study was to examine the determinants of audit report lag in the Nigerian context. Specifically, the study examined the effects of the following factors on Audit fees; Audit firm type, Leverage, Return on equity, Firm size, subsidiaries and Year-end. The panel research design was used for the study. The data was sourced from the annual reports of all financial companies quoted on the floor of the Nigerian stock exchange. The method of data analysis utilized in the study is the panel data estimation techniques (pooled, fixed and random effects regression. In line with the study objectives, the finding reveals that (i Company size has no significant positive impact on audit delay. (ii Firm’s financial performance has a significant impact on Audit delay. (iii Audit firm type (big 4 and non-big 4 has a significant impact on Audit delay. (iv Leverage has no significant impact on Audit delay and (v Number of subsidiaries has a significant impact on Audit delay and (vi Financial year end has no significant impact on Audit delay. The recommendation is that in achieving the objective of making the financial statements readily available for making timely decisions, the Nigerian stock exchange, Securities and Exchange Commission, the Financial Reporting Council, the Central Bank of Nigeria and other regulatory bodies should put in place measures to ensure strict compliance with 3 months window for financial reports preparation and presentation.

  1. The reasons for delay lumbar puncture

    Directory of Open Access Journals (Sweden)

    MH. Lotfi

    2017-04-01

    Full Text Available Early diagnosis of meningitis and encephalitis and prompt initiation of appropriate therapy is vital and any delay will lead to high mortality and serious and permanent morbidity. The main purpose of this study was to evaluate the management of 220 patients with suspected central nervous system (CNS infections (meningitis and encephalitis to determine the percentage of patients’ suspected CNS infection undergo lumbar puncture in acceptable time (in accordance with conventional algorithms. In this descriptive study, patients with suspected CNS infections admitted to Bu-Ali and Qods hospitals, in the period July 2013 to December 2015 were studied. Information of 220 patients was collected. Continuous variables were summarized as means ± standard deviation and categorical variables as frequencies and percentages. Lumbar puncture (LP in patients was delayed in 200 cases (91%. Most common causes of delay in performing LP were prolongation of the process of determining patient needs to puncture, satisfying patients, CT scan delay and the delay in allowing LP by neurologist. In this study, delaying LP rate was higher than other studies. It seems certain pattern in assistants’ visits for counseling. CT requests and neurologic consultation before LP performed for all adult patients.

  2. Covariant electromagnetic field lines

    Science.gov (United States)

    Hadad, Y.; Cohen, E.; Kaminer, I.; Elitzur, A. C.

    2017-08-01

    Faraday introduced electric field lines as a powerful tool for understanding the electric force, and these field lines are still used today in classrooms and textbooks teaching the basics of electromagnetism within the electrostatic limit. However, despite attempts at generalizing this concept beyond the electrostatic limit, such a fully relativistic field line theory still appears to be missing. In this work, we propose such a theory and define covariant electromagnetic field lines that naturally extend electric field lines to relativistic systems and general electromagnetic fields. We derive a closed-form formula for the field lines curvature in the vicinity of a charge, and show that it is related to the world line of the charge. This demonstrates how the kinematics of a charge can be derived from the geometry of the electromagnetic field lines. Such a theory may also provide new tools in modeling and analyzing electromagnetic phenomena, and may entail new insights regarding long-standing problems such as radiation-reaction and self-force. In particular, the electromagnetic field lines curvature has the attractive property of being non-singular everywhere, thus eliminating all self-field singularities without using renormalization techniques.

  3. The Limitations to Delay-Insensitivity in Asynchronous Circuits

    National Research Council Canada - National Science Library

    Martin, Alain J

    1990-01-01

    ... produced are delay-insensitive (DI). A digital circuit is DI when its correct operation is independent of the delays in operators and in the wires connecting the operators, except that the delays are finite and positive...

  4. Lag synchronization of chaotic systems with time-delayed linear ...

    Indian Academy of Sciences (India)

    delayed linear terms via impulsive control is investigated. Based on the stability theory of impulsive delayed differen- tial equations, some sufficient conditions are obtained guaranteeing the synchronized behaviours between two delayed chaotic ...

  5. The molecular basis for cell cycle delays following ionizing radiation. A review

    International Nuclear Information System (INIS)

    Maity, A.; McKenna, W.G.; Muschel, R.J.

    1994-01-01

    Exposure of a wide variety of cells to ionizing (X- or γ-) irradiation results in a division delay which may have several components including a G 1 block, a G 2 arrest or an S phase delay. The G 1 arrest is absent in many cells lines, and the S phase delay is typically seen following relatively high doses (>5 Gy). In contrast, the G 2 arrest is seen in virtually all eukaryotic cells and occurs following high and low doses, even under 1 Gy. The mechanism underlying the G 2 arrest may involve suppression of cyclin B1 mRNA and/or protein in some cell lines and tyrosine phosphorylation of p34 cdc2 in others. Similar mechanisms are likely to be operative in the G 2 arrest induced by various chemotherapeutic agents including nitrogen mustard and etoposide. The upstream signal transduction pathways involved in the G 2 arrest following ionizing radiation remain obscure in mammalian cells; however, in the budding yeast the rad9 gene and in the fission yeast the chk1/rad27 gene are involved. There is evidence indicating that shortening of the G 2 arrest results in decreased survival which has led to the hypothesis that during this block, cells repair damaged DNA following exposure to genotoxic agents. In cell lines examined to date, wildtype p53 is required for the G 1 arrest following ionizing radiation. The gadd45 gene may also have a role in this arrest. Elimination of the G 1 arrest leads to no change in survival following radiation in some cell lines and increased radioresistance in others. It has been suggested that this induction of radioresistance in certain cell lines is due to loss of the ability to undergo apoptosis. Relatively little is known about the mechanism underlying the S phase delay. This delay is due to a depression in the rate of DNA synthesis and has both a slow and a fast component. In some cells the S phase delay can be abolished by staurosporine, suggesting involvement of a protein kinase. Understanding the molecular mechanisms behind these delays

  6. Virtual unit delay for digital frequency adaptive T/4 delay phase-locked loop system

    DEFF Research Database (Denmark)

    Yang, Yongheng; Zhou, Keliang; Blaabjerg, Frede

    2016-01-01

    /processor with a fixed sampling rate considering the cost and complexity, where the number of unit delays that have been adopted should be an integer. For instance, in conventional digital control systems, a single-phase T/4 Delay Phase-Locked Loop (PLL) system takes 50 unit delays (i.e., in a 50-Hz system...... Delay PLL system should be done in its implementation. This process will result in performance degradation in the digital control system, as the exactly required number of delays is not realized. Hence, in this paper, a Virtual Unit Delay (VUD) has been proposed to address such challenges to the digital......Digital micro-controllers/processors enable the cost-effective control of grid-connected power converter systems in terms of system monitoring, signal processing (e.g., grid synchronization), control (e.g., grid current and voltage control), etc. Normally, the control is implemented in a micro-controller...

  7. Improving Delay-Range-Dependent Stability Condition for Systems with Interval Time-Varying Delay

    Directory of Open Access Journals (Sweden)

    Wei Qian

    2013-01-01

    Full Text Available This paper discusses the delay-range-dependent stability for systems with interval time-varying delay. Through defining the new Lyapunov-Krasovskii functional and estimating the derivative of the LKF by introducing new vectors, using free matrices and reciprocally convex approach, the new delay-range-dependent stability conditions are obtained. Two well-known examples are given to illustrate the less conservatism of the proposed theoretical results.

  8. Leveraging delay discounting for health: Can time delays influence food choice?

    Science.gov (United States)

    Appelhans, Bradley M; French, Simone A; Olinger, Tamara; Bogucki, Michael; Janssen, Imke; Avery-Mamer, Elizabeth F; Powell, Lisa M

    2018-03-15

    Delay discounting, the tendency to choose smaller immediate rewards over larger delayed rewards, is theorized to promote consumption of immediately rewarding but unhealthy foods at the expense of long-term weight maintenance and nutritional health. An untested implication of delay discounting models of decision-making is that selectively delaying access to less healthy foods may promote selection of healthier (immediately available) alternatives, even if they may be less desirable. The current study tested this hypothesis by measuring healthy versus regular vending machine snack purchasing before and during the implementation of a 25-s time delay on the delivery of regular snacks. Purchasing was also examined under a $0.25 discount on healthy snacks, a $0.25 tax on regular snacks, and the combination of both pricing interventions with the 25-s time delay. Across 32,019 vending sales from three separate vending locations, the 25-s time delay increased healthy snack purchasing from 40.1% to 42.5%, which was comparable to the impact of a $0.25 discount (43.0%). Combining the delay and the discount had a roughly additive effect (46.0%). However, the strongest effects were seen under the $0.25 tax on regular snacks (53.7%) and the combination of the delay and the tax (50.2%). Intervention effects varied substantially between vending locations. Importantly, time delays did not harm overall vending sales or revenue, which is relevant to the real-world feasibility of this intervention. More investigation is needed to better understand how the impact of time delays on food choice varies across populations, evaluate the effects of time delays on beverage vending choices, and extend this approach to food choices in contexts other than vending machines. ClinicalTrials.gov, NCT02359916. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. On line portal imaging

    International Nuclear Information System (INIS)

    Munro, Peter

    1995-01-01

    Purpose/Objective: The purpose of this presentation is to review the physics of imaging with high energy x-ray beams; examine the various imaging devices that have been developed for portal imaging; describe some of the image registration methods that have been developed to determine errors in patient positioning quantitatively; and discuss some of the ways that portal imaging has been incorporated into routine clinical practice. Verification of patient positioning has always been an important aspect of external beam radiation therapy. Checks of patient positioning have generally been done with film, however, film suffers from a number of drawbacks, such as poor image display and delays due to film development. Over the past decade many portal imaging devices have been developed by individual investigators and most accelerator manufacturers now offer 'on-line' portal imaging systems, which are intended to overcome the limitations of portal films. The commercial devices can be classified into three categories: T.V. camera-based systems, liquid ionisation chamber systems, and amorphous silicon systems. Many factors influence the quality of images generated by these portal imaging systems. These include factors which are unavoidable (e.g., low subject contrast), factors which depend upon the individual imaging device forming the image (e.g., dose utilisation, spatial resolution) as well as factors which depend upon the characteristics of the linear accelerator irradiating the imaging system (x-ray source size, image magnification). The fundamental factors which limit image quality and the characteristics of individual imaging systems, such as spatial resolution, temporal response, and quantum utilisation will be discussed. One of the major advantages of on-line portal imaging is that many quantitative techniques have been developed to detect errors in patient positioning. The general approach is to register anatomic structures on a portal image with the same

  10. Derivation and computation of discrete-delay and continuous-delay SDEs in mathematical biology.

    Science.gov (United States)

    Allen, Edward J

    2014-06-01

    Stochastic versions of several discrete-delay and continuous-delay differential equations, useful in mathematical biology, are derived from basic principles carefully taking into account the demographic, environmental, or physiological randomness in the dynamic processes. In particular, stochastic delay differential equation (SDDE) models are derived and studied for Nicholson's blowflies equation, Hutchinson's equation, an SIS epidemic model with delay, bacteria/phage dynamics, and glucose/insulin levels. Computational methods for approximating the SDDE models are described. Comparisons between computational solutions of the SDDEs and independently formulated Monte Carlo calculations support the accuracy of the derivations and of the computational methods.

  11. Global synchronization criteria with channel time-delay for chaotic time-delay system

    International Nuclear Information System (INIS)

    Sun Jitao

    2004-01-01

    Based on the Lyapunov stabilization theory, matrix measure, and linear matrix inequality (LMIs), this paper studies the chaos synchronization of time-delay system using the unidirectional linear error feedback coupling with time-delay. Some generic conditions of chaos synchronization with time-delay in the transmission channel is established. The chaotic Chua's circuit is used for illustration, where the coupling parameters are determined according to the criteria under which the global chaos synchronization of the time-delay coupled systems is achieved

  12. Prehospital delay in acute coronary syndrome--an analysis of the components of delay

    DEFF Research Database (Denmark)

    Ottesen, Michael Mundt; Dixen, Ulrik; Torp-Pedersen, Christian

    2004-01-01

    BACKGROUND: Prompt hospital admission is essential when treating acute coronary syndrome. Delay prior to admission is unnecessarily long. Therefore, a thorough scrutiny of the influence of characteristics, circumstantial and subjective variables on elements of prehospital delay among patients...... admitted with acute coronary syndrome is warranted. METHODS: A structured interview was conducted on 250 consecutive patients admitted alive with acute coronary syndrome. RESULTS: Median prehospital, decision, physician and transportation delays were 107, 74, 25 and 22 min, respectively. Women (n=77) had...... of acute coronary syndrome among women, and thereby contributes to unnecessary long delay to treatment. The patient's prior experience and interpretation has a significant influence on behaviour....

  13. Is immediate adjunctive CBT more beneficial than delayed CBT in treating depression?: A Pilot Study.

    Science.gov (United States)

    Rizvi, Sakina J; Zaretsky, Ari; Schaffer, Ayal; Levitt, Anthony

    2015-03-01

    Cognitive-behavioral therapy (CBT) is an efficacious first-line therapy for patients with major depressive disorder (MDD). Due to the limited accessibility of CBT, long wait lists result in delayed treatment, which may affect treatment outcomes. The goal of this pilot study was to obtain preliminary data from a randomized controlled trial to determine whether delayed CBT reduces the effectiveness of the therapy compared to immediate CBT in patients with MDD receiving pharmacotherapy. Patients were randomized to receive immediate CBT (n=18) or to begin CBT after 6 months (n=20) and received 14 weekly sessions, followed by two additional booster sessions. During the active treatment months, patients in the immediate group demonstrated reductions in scores on the Beck Depression Inventory II (BDI-II) that were similar to those in the delayed CBT group. However, when the analysis was performed using only data from patients in the delayed group who were still in a depressive episode, there was an overall greater decrease in BDI-II scores in the immediate group vs. the delayed group over the active treatment months, but not specifically at the 6-month endpoint. These findings suggest delays in depression treatment, similar to what occurs with real-world wait list times, may not have a significant impact on the effectiveness of CBT in patients who are already receiving treatment as usual. However, such delays may affect the effectiveness of CBT in those patients who remain depressed during the time delay. A larger trial is necessary to confirm these findings. (Journal of Psychiatric Practice 2015;21:107-113).

  14. Semi-on-line analysis for fast and precise monitoring of bioreaction processes

    DEFF Research Database (Denmark)

    Christensen, L.H.; Marcher, J.; Schulze, Ulrik

    1996-01-01

    Monitoring of substrates and products during fermentation processes can be achieved either by on-line, in situ sensors or by semi-on-line analysis consisting of an automatic sampling step followed by an ex situ analysis of the retrieved sample. The potential risk of introducing time delays...

  15. Minnesota County Boundaries - lines

    Data.gov (United States)

    Minnesota Department of Natural Resources — Minnesota county boundaries derived from a combination of 1:24,000 scale PLS lines, 1:100,000 scale TIGER, 1:100,000 scale DLG, and 1:24,000 scale hydrography lines....

  16. Database of emission lines

    Science.gov (United States)

    Binette, L.; Ortiz, P.; Joguet, B.; Rola, C.

    1998-11-01

    A widely accessible data bank (available through Netscape) and consiting of all (or most) of the emission lines reported in the litterature is being built. It will comprise objects as diverse as HII regions, PN, AGN, HHO. One of its use will be to define/refine existing diagnostic emission line diagrams.

  17. Impulsive control of time-delay systems using delayed impulse and its application to impulsive master-slave synchronization

    International Nuclear Information System (INIS)

    Sun Jitao; Han Qinglong; Jiang Xiefu

    2008-01-01

    This Letter is concerned with impulsive control of a class of nonlinear time-delay systems. Some uniform stability criteria for the closed-loop time-delay system under delayed impulsive control are derived by using piecewise Lyapunov functions. Then the criteria are applied to impulsive master-slave synchronization of some secure communication systems with transmission delays and sample delays under delayed impulsive control. Two numerical examples are given to illustrate the effectiveness of the derived results

  18. Semi-continuous on-line uranium ore analyzer

    International Nuclear Information System (INIS)

    Campbell, P.; Gurdy, E.M.; Hatchowski, L.

    1984-01-01

    The efficient process control of a uranium mill and its associated mining operation requires a nearly continuous knowledge of the uranium concentration in the ore. Generally, the approach is to use laboratory assays of grab samples from the mill feed belt. In some cases, elaborate and expensive systems have been used to ensure random sampling, but even with these systems, mass-balance discrepancies still exist. There is a requirement for an on-line instrument that can give a prompt, accurate analysis of a large portion of the feed stock. The authors have recently evaluated a laboratory system that achieves these goals using neutron activation and delayed neutron counting. The development of the on-line uranium ore analyzer is a consequence of previous work done at the Whiteshell Nuclear Research Establishment (WNRE) (Campbell et al., 1978 and 1981), and is based on the emission of delayed neutrons after the neutron irradiation of fissionable materials. The mechanism of delayed neutron emission has been described (Keepin, 1965), but briefly is as follows. The fission fragments resulting from irradiation are in an excited state. Certain of these delayed fission products, precursors, decay to a more stable state by the emission of a delayed neutron. The delayed neutrons can be divided into six groups with effective half-lives ranging from 0.2-55 sec. It is important to note that more than 50% of the delayed neutrons are emitted within the first 6 sec after irradiation; this has an influence on the design of the analysis instrument

  19. A delayed presentation of ameloblastic fibrosarcoma in an African patient.

    Science.gov (United States)

    Chauke, Nkhensani Yvonne; Sofianos, Chrysis; Liakos, Dimitri; Ndobe, Elias

    2017-08-01

    A 24-year-old womanpresented with ameloblastic fibrosarcoma arising from ameloblastic fibroma. The delayed presentation accounted for the extensive destruction of the mandible and complete occlusion of her oral cavity. This resulted in an inability to eat and maintain oral hygiene. A multidisciplinary team management approach involved nutritional optimisation, segmental mandibulectomy, reconstruction with a reconstructive plate and a free anterolateral thigh flap to line the the floor of mouth. Functional and aesthetic outcome was acceptable, and the patient is planned for secondary free fibular flap bony reconstruction. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  20. Delay in solar energetic particle onsets at high heliographic latitudes

    Directory of Open Access Journals (Sweden)

    S. Dalla

    2003-06-01

    Full Text Available Ulysses observations have shown that solar energetic particles (SEPs can easily reach high heliographic latitudes. To obtain information on the release and propagation of SEPs prior to their arrival at Ulysses, we analyse the onsets of nine large high-latitude particle events. We measure the onset times in several energy channels, and plot them versus inverse particle speed. This allows us to derive an experimental path length and time of release from the solar atmosphere. We repeat the procedure for near-Earth observations by Wind and SOHO. We find that the derived path lengths at Ulysses are 1.06 to 2.45 times the length of a Parker spiral magnetic field line connecting the spacecraft to the Sun. The time of particle release from the Sun is between 100 and 350 min later than the release time derived from in-ecliptic measurements. We find no evidence of correlation between the delay in release and the inverse of the speed of the CME associated with the event, or the inverse of the speed of the corresponding interplanetary shock. The main parameter determining the magnitude of the delay appears to be the difference in latitude between the flare and the footpoint of the spacecraft.Key words. Interplanetary physics (energetic particles – Solar physics, astrophysics and astronomy (energetic particles, flares and mass ejections

  1. A dynamic IS-LM model with delayed taxation revenues

    International Nuclear Information System (INIS)

    De Cesare, Luigi; Sportelli, Mario

    2005-01-01

    Some recent contributions to Economic Dynamics have shown a new interest for delay differential equations. In line with these approaches, we re-proposed the problem of the existence of a finite lag between the accrual and the payment of taxes in a framework where never this type of lag has been considered: the well known IS-LM model. The qualitative study of the system of functional (delay) differential equations shows that the finite lag may give rise to a wide variety of dynamic behaviours. Specifically, varying the length of the lag and applying the 'stability switch criteria', we prove that the equilibrium point may lose or gain its local stability, so that a sequence of alternated stability/instability regions can be observed if some conditions hold. An important scenario arising from the analysis is the existence of limit cycles generated by sub-critical and supercritical Hopf bifurcations. As numerical simulations confirm, if multiple cycles exist, the so called 'crater bifurcation' can also be detected. Economic considerations about a stylized policy analysis stand by qualitative and numerical results in the paper

  2. Facilitating tolerance of delayed reinforcement during functional communication training.

    Science.gov (United States)

    Fisher, W W; Thompson, R H; Hagopian, L P; Bowman, L G; Krug, A

    2000-01-01

    Few clinical investigations have addressed the problem of delayed reinforcement. In this investigation, three individuals whose destructive behavior was maintained by positive reinforcement were treated using functional communication training (FCT) with extinction (EXT). Next, procedures used in the basic literature on delayed reinforcement and self-control (reinforcer delay fading, punishment of impulsive responding, and provision of an alternative activity during reinforcer delay) were used to teach participants to tolerate delayed reinforcement. With the first case, reinforcer delay fading alone was effective at maintaining low rates of destructive behavior while introducing delayed reinforcement. In the second case, the addition of a punishment component reduced destructive behavior to near-zero levels and facilitated reinforcer delay fading. With the third case, reinforcer delay fading was associated with increases in masturbation and head rolling, but prompting and praising the individual for completing work during the delay interval reduced all problem behaviors and facilitated reinforcer delay fading.

  3. Delayed neutrons in liquid metal spallation targets

    International Nuclear Information System (INIS)

    Ridikas, D.; Bokov, P.; David, J.C.; Dore, D.; Giacri, M.L.; Van Lauwe, A.; Plukiene, R.; Plukis, A.; Ignatiev, S.; Pankratov, D.

    2003-01-01

    The next generation spallation neutron sources, neutrino factories or RIB production facilities currently being designed and constructed around the world will increase the average proton beam power on target by a few orders of magnitude. Increased proton beam power results in target thermal hydraulic issues leading to new target designs, very often based on flowing liquid metal targets such as Hg, Pb, Pb-Bi. Radioactive nuclides produced in liquid metal targets are transported into hot cells, past electronics, into pumps with radiation sensitive components, etc. Besides the considerable amount of photon activity in the irradiated liquid metal, a significant amount of the delayed neutron precursor activity can be accumulated in the target fluid. The transit time from the front of a liquid metal target into areas, where delayed neutrons may be important, can be as short as a few seconds, well within one half-life of many delayed neutron precursors. Therefore, it is necessary to evaluate the total neutron flux (including delayed neutrons) as a function of time and determine if delayed neutrons contribute significantly to the dose rate. In this study the multi-particle transport code MCNPX combined with the material evolution program CINDER'90 will be used to evaluate the delayed neutron flux and spectra. The following scientific issues will be addressed in this paper: - Modeling of a typical geometry of the liquid metal spallation target; - Predictions of the prompt neutron fluxes, fission fragment and spallation product distributions; - Comparison of the above parameters with existing experimental data; - Time-dependent calculations of delayed neutron precursors; - Neutron flux estimates due to the prompt and delayed neutron emission; - Proposal of an experimental program to measure delayed neutron spectra from high energy spallation-fission reactions. The results of this study should be directly applicable in the design study of the European MegaPie (1 MW

  4. Data Assimilation by delay-coordinate nudging

    Science.gov (United States)

    Pazo, Diego; Lopez, Juan Manuel; Carrassi, Alberto

    2016-04-01

    A new nudging method for data assimilation, delay-coordinate nudging, is presented. Delay-coordinate nudging makes explicit use of present and past observations in the formulation of the forcing driving the model evolution at each time-step. Numerical experiments with a low order chaotic system show that the new method systematically outperforms standard nudging in different model and observational scenarios, also when using an un-optimized formulation of the delay-nudging coefficients. A connection between the optimal delay and the dominant Lyapunov exponent of the dynamics is found based on heuristic arguments and is confirmed by the numerical results, providing a guideline for the practical implementation of the algorithm. Delay-coordinate nudging preserves the easiness of implementation, the intuitive functioning and the reduced computational cost of the standard nudging, making it a potential alternative especially in the field of seasonal-to-decadal predictions with large Earth system models that limit the use of more sophisticated data assimilation procedures.

  5. Television viewing associates with delayed language development.

    Science.gov (United States)

    Chonchaiya, Weerasak; Pruksananonda, Chandhita

    2008-07-01

    To identify impact of television viewing on language development. The case-control study included 56 new patients with language delay and 110 normal children, aged 15-48 months. Language delay was diagnosed by reviewing language milestones and Denver-II. Television viewing variables and child/parental characteristics between both groups were interviewed. The data were analyzed by ANOVA and chi-square test. Adjusted odds ratios and 95% confidence intervals were calculated from multivariate logistic regression model. Forty-six boys and 10 girls; mean [+/-SD] age, 2.11+/-0.47 years of the case group and 59 boys and 51 girls; mean [+/-SD] age, 2.23+/-0.80 years of the control group were enrolled. Children who had language delay usually started watching television earlier at age 7.22+/-5.52 months vs. 11.92+/-5.86 months, p-valuetelevision than normal children (3.05+/-1.90 h/day vs. 1.85+/-1.18 h/day; p-valuetelevision attelevision>2 h/day were approximately six times more likely to have language delays. There is a relationship between early onset and high frequency of TV viewing and language delay.

  6. Theory of attosecond delays in molecular photoionization.

    Science.gov (United States)

    Baykusheva, Denitsa; Wörner, Hans Jakob

    2017-03-28

    We present a theoretical formalism for the calculation of attosecond delays in molecular photoionization. It is shown how delays relevant to one-photon-ionization, also known as Eisenbud-Wigner-Smith delays, can be obtained from the complex dipole matrix elements provided by molecular quantum scattering theory. These results are used to derive formulae for the delays measured by two-photon attosecond interferometry based on an attosecond pulse train and a dressing femtosecond infrared pulse. These effective delays are first expressed in the molecular frame where maximal information about the molecular photoionization dynamics is available. The effects of averaging over the emission direction of the electron and the molecular orientation are introduced analytically. We illustrate this general formalism for the case of two polyatomic molecules. N 2 O serves as an example of a polar linear molecule characterized by complex photoionization dynamics resulting from the presence of molecular shape resonances. H 2 O illustrates the case of a non-linear molecule with comparably simple photoionization dynamics resulting from a flat continuum. Our theory establishes the foundation for interpreting measurements of the photoionization dynamics of all molecules by attosecond metrology.

  7. Time delay interferometry with moving spacecraft arrays

    International Nuclear Information System (INIS)

    Tinto, Massimo; Estabrook, F.B.; Armstrong, J.W.

    2004-01-01

    Space-borne interferometric gravitational wave detectors, sensitive in the low-frequency (millihertz) band, will fly in the next decade. In these detectors the spacecraft-to-spacecraft light-travel-times will necessarily be unequal, time varying, and (due to aberration) have different time delays on up and down links. The reduction of data from moving interferometric laser arrays in solar orbit will in fact encounter nonsymmetric up- and down-link light time differences that are about 100 times larger than has previously been recognized. The time-delay interferometry (TDI) technique uses knowledge of these delays to cancel the otherwise dominant laser phase noise and yields a variety of data combinations sensitive to gravitational waves. Under the assumption that the (different) up- and down-link time delays are constant, we derive the TDI expressions for those combinations that rely only on four interspacecraft phase measurements. We then turn to the general problem that encompasses time dependence of the light-travel times along the laser links. By introducing a set of noncommuting time-delay operators, we show that there exists a quite general procedure for deriving generalized TDI combinations that account for the effects of time dependence of the arms. By applying our approach we are able to re-derive the 'flex-free' expression for the unequal-arm Michelson combinations X 1 , and obtain the generalized expressions for the TDI combinations called relay, beacon, monitor, and symmetric Sagnac

  8. Investigation of delayed fission gas release

    International Nuclear Information System (INIS)

    Cayet, Nicolas

    1996-05-01

    The study of the fission gas release process in the high burnup rig IFA-562 has revealed a particular fuel behaviour: a delay in the fission gas release process. It appeared that an important release of gas was measured by the pressure transducers once the power had decreased, whereas, during steady-state operation, the pressure did not increase very much. After examinations, the gap size has been concluded to be the main parameter involving this delay. However the burnup could have been a potential factor, its role is mainly to close the gap by swelling. The observations of low burnup rods have shown the same delayed fission gas release, the gap being small by design and closed essentially by thermal expansion. The study of the kinetics has demonstrated the time-independency of the phenomenon. Thus the proposed mechanism driving this delayed fission gas release would involve three consecutives stages. During steady-state, the gas is released into the interlinkage network of grain boundary bubbles and cracks. Due to the closed gap, the gas is trapped in some void volumes, unable to escape the pellet. During power reduction, the gap and some old/new cracks open, immediately providing a path for the gas to the pressure transducers and explaining this delay in the fission gas release. (author)

  9. Communication key using delay times in time-delayed chaos synchronization

    International Nuclear Information System (INIS)

    Kim, Chil-Min; Kye, Won-Ho; Rim, Sunghwan; Lee, Soo-Young

    2004-01-01

    We propose an efficient key scheme, which can generate a great number of communication keys, for communication using chaos synchronization. We have attained the keys from delay times of time-delay coupled chaotic systems. We explain the scheme and the efficiency by coupling Henon and logistic maps and illustrate them by coupling Navier-Stokes and Lorenz equations as a continuous system

  10. Wood pole overhead lines

    CERN Document Server

    Wareing, Brian

    2005-01-01

    This new book concentrates on the mechanical aspects of distribution wood pole lines, including live line working, environmental influences, climate change and international standards. Other topics include statutory requirements, safety, profiling, traditional and probabilistic design, weather loads, bare and covered conductors, different types of overhead systems, conductor choice, construction and maintenance. A section has also been devoted to the topic of lightning, which is one of the major sources of faults on overhead lines. The book focuses on the effects of this problem and the strate

  11. Time-delayed autosynchronous swarm control.

    Science.gov (United States)

    Biggs, James D; Bennet, Derek J; Dadzie, S Kokou

    2012-01-01

    In this paper a general Morse potential model of self-propelling particles is considered in the presence of a time-delayed term and a spring potential. It is shown that the emergent swarm behavior is dependent on the delay term and weights of the time-delayed function, which can be set to induce a stationary swarm, a rotating swarm with uniform translation, and a rotating swarm with a stationary center of mass. An analysis of the mean field equations shows that without a spring potential the motion of the center of mass is determined explicitly by a multivalued function. For a nonzero spring potential the swarm converges to a vortex formation about a stationary center of mass, except at discrete bifurcation points where the center of mass will periodically trace an ellipse. The analytical results defining the behavior of the center of mass are shown to correspond with the numerical swarm simulations.

  12. Positive mood effects on delay discounting.

    Science.gov (United States)

    Hirsh, Jacob B; Guindon, Alex; Morisano, Dominique; Peterson, Jordan B

    2010-10-01

    Delay discounting is the process by which the value of an expected reward decreases as the delay to obtaining that reward increases. Individuals with higher discounting rates tend to prefer smaller immediate rewards over larger delayed rewards. Previous research has indicated that personality can influence an individual's discounting rates, with higher levels of Extraversion predicting a preference for immediate gratification. The current study examined how this relationship would be influenced by situational mood inductions. While main effects were observed for both Extraversion and cognitive ability in the prediction of discounting rates, a significant interaction was also observed between Extraversion and positive affect. Extraverted individuals were more likely to prefer an immediate reward when first put in a positive mood. Extraverts thus appear particularly sensitive to impulsive, incentive-reward-driven behavior by temperament and by situational factors heightening positive affect. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  13. Delays in the management of retroperitoneal sarcomas

    DEFF Research Database (Denmark)

    Seinen, Jojanneke; Almquist, Martin; Styring, Emelie

    2010-01-01

    Retroperitoneal sarcomas are rare and treatment should optimally be centralized. Despite successful centralization with 90% of the patients referred prior to surgery, delays occur, which led us to assess lead times in a population-based series. Method. Patients diagnosed with retroperitoneal...... sarcoma in the southern Sweden health care region 2003-2009 were eligible for the study. Data on referrals and diagnostic investigations were collected from clinical files from primary health care, local hospitals, and from the sarcoma centre. Lead times were divided into patient delays and health care...... at the general practitioner, 36 days at local hospitals, and 55 days at the sarcoma centre. Conclusion. Centralization per se is not sufficient for optimized and efficient management. Our findings suggest that delays can be minimized by direct referral of patients from primary health care to sarcoma centers...

  14. On stochastic differential equations with random delay

    International Nuclear Information System (INIS)

    Krapivsky, P L; Luck, J M; Mallick, K

    2011-01-01

    We consider stochastic dynamical systems defined by differential equations with a uniform random time delay. The latter equations are shown to be equivalent to deterministic higher-order differential equations: for an nth-order equation with random delay, the corresponding deterministic equation has order n + 1. We analyze various examples of dynamical systems of this kind, and find a number of unusual behaviors. For instance, for the harmonic oscillator with random delay, the energy grows as exp((3/2) t 2/3 ) in reduced units. We then investigate the effect of introducing a discrete time step ε. At variance with the continuous situation, the discrete random recursion relations thus obtained have intrinsic fluctuations. The crossover between the fluctuating discrete problem and the deterministic continuous one as ε goes to zero is studied in detail on the example of a first-order linear differential equation

  15. Delay time and tunneling transient phenomena

    International Nuclear Information System (INIS)

    Garcia-Calderon, Gaston; Villavicencio, Jorge

    2002-01-01

    Analytic solutions to the time-dependent Schroedinger equation for cutoff wave initial conditions are used to investigate the time evolution of the transmitted probability density for tunneling. For a broad range of values of the potential barrier opacity α, we find that the probability density exhibits two evolving structures. One refers to the propagation of a forerunner related to a time domain resonance [Phys. Rev. A 64, 0121907 (2001)], while the other consists of a semiclassical propagating wave front. We find a regime where the forerunners are absent, corresponding to positive time delays, and show that this regime is characterized by opacities α c . The critical opacity α c is derived from the analytical expression for the delay time, which reflects a link between transient effects in tunneling and the delay time

  16. Delayed switching applied to memristor neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Frank Z.; Yang Xiao; Lim Guan [Future Computing Group, School of Computing, University of Kent, Canterbury (United Kingdom); Helian Na [School of Computer Science, University of Hertfordshire, Hatfield (United Kingdom); Wu Sining [Xyratex, Havant (United Kingdom); Guo Yike [Department of Computing, Imperial College, London (United Kingdom); Rashid, Md Mamunur [CERN, Geneva (Switzerland)

    2012-04-01

    Magnetic flux and electric charge are linked in a memristor. We reported recently that a memristor has a peculiar effect in which the switching takes place with a time delay because a memristor possesses a certain inertia. This effect was named the ''delayed switching effect.'' In this work, we elaborate on the importance of delayed switching in a brain-like computer using memristor neural networks. The effect is used to control the switching of a memristor synapse between two neurons that fire together (the Hebbian rule). A theoretical formula is found, and the design is verified by a simulation. We have also built an experimental setup consisting of electronic memristive synapses and electronic neurons.

  17. Delayed switching applied to memristor neural networks

    International Nuclear Information System (INIS)

    Wang, Frank Z.; Yang Xiao; Lim Guan; Helian Na; Wu Sining; Guo Yike; Rashid, Md Mamunur

    2012-01-01

    Magnetic flux and electric charge are linked in a memristor. We reported recently that a memristor has a peculiar effect in which the switching takes place with a time delay because a memristor possesses a certain inertia. This effect was named the ''delayed switching effect.'' In this work, we elaborate on the importance of delayed switching in a brain-like computer using memristor neural networks. The effect is used to control the switching of a memristor synapse between two neurons that fire together (the Hebbian rule). A theoretical formula is found, and the design is verified by a simulation. We have also built an experimental setup consisting of electronic memristive synapses and electronic neurons.

  18. Delayed feedback control in quantum transport.

    Science.gov (United States)

    Emary, Clive

    2013-09-28

    Feedback control in quantum transport has been predicted to give rise to several interesting effects, among them quantum state stabilization and the realization of a mesoscopic Maxwell's daemon. These results were derived under the assumption that control operations on the system are affected instantaneously after the measurement of electronic jumps through it. In this contribution, I describe how to include a delay between detection and control operation in the master equation theory of feedback-controlled quantum transport. I investigate the consequences of delay for the state stabilization and Maxwell's daemon schemes. Furthermore, I describe how delay can be used as a tool to probe coherent oscillations of electrons within a transport system and how this formalism can be used to model finite detector bandwidth.

  19. Radiochemical Means of Investigating Delayed Neutron Precursors

    International Nuclear Information System (INIS)

    Marmol, P. del

    1968-01-01

    Fast radiochemical methods used now for the determination of delayed neutron precursors are classified and reviewed: precipitations, solvent extractions, range experiments, milking, gas sweeping, isotopic and ion exchange, hot atom reactions and diffusion loss. Advantages and limitations of irradiation systems with respect to fast separations are discussed: external beams which allow faster separations only have low neutron fluxes, internal beams which are mostly fit for gaseous reactions; and rabbits for solution irradiations. Future prospects of radiochemical procedures are presented; among these, studies should be mostly oriented towards gaseous reactions which offer possibilities of isolating very short-lived delayed neutron precursors. Chemical procedures for delayed neutron precursor detection are compared with mass spectrometric and isotope separator techniques; it is concluded that the methods are complementary. (author)

  20. Radiochemical Means of Investigating Delayed Neutron Precursors

    International Nuclear Information System (INIS)

    Marmol, P. del

    1968-01-01

    Fast radiochemical methods used now for the determination of delayed neutron precursors are classified and reviewed: precipitations, solvent extractions, range experiments, milking, gas sweeping, isotopic and ion exchange, hot-atom reactions and diffusion loss. Advantages and limitations of irradiation systems with respect to fast separations are discussed: external beams which allow faster separations only have low neutron fluxes, internal beams which are mostly fit for gaseous reactions; and rabbits for solution irradiations. Future prospects of radiochemical procedures are presented; among these, studies should be mostly oriented towards gaseous reactions which offer possibilities of isolating very short-lived delayed neutron precursors. Chemical procedures for delayed neutron precursor detection are compared with mass spectrometric and isotope-separator techniques; it is concluded that the methods are complementary. (author)

  1. Abdominal CT findings of delayed postoperative complications

    Energy Technology Data Exchange (ETDEWEB)

    Zissin, R.; Osadchy, A. [Sapir Medical Center, Dept. of Diagnostic Imaging, Kfar Saba (Israel)]. E-mail: zisinrivka@clalit.org.il; Gayer, G. [Assaf Harofe Medical Center, Dept. of Diagnostic Imaging, Zrifin (Israel)

    2007-10-15

    Despite progress in surgical techniques and modern medical treatment, postoperative complications occur not infrequently and vary according to type of surgery, clinical setting, and time elapsed since surgery. In general, they can be divided into early and delayed complications. Delayed postoperative complications can be classified as specific and nonspecific. The common nonspecific delayed complications are incisional hernia and postoperative bowel obstruction. Bowel obstruction can be further categorized as obstruction related to benign or neoplastic etiology, the latter occurring in oncology patients in whom the primary surgery was related to an underlying abdominal neoplasm. Gossypiboma is another, fortunately rare, postoperative complication. Specific complications appear after specific operations and include the following: Splenosis - following splenectomy. Retained gallstones and spilled gallstones - following cholecystectomy, mainly laparoscopic. Dropped appendicolith and stump appendicitis - following appendectomy, mainly laparoscopic. Obturation obstruction by a bezoar - following gastric surgery. Afferent loop syndrome (ALS) - following Bilroth II gastrectomy. (author)

  2. A delay fractioning approach to global synchronization of delayed complex networks with stochastic disturbances

    International Nuclear Information System (INIS)

    Wang Yao; Wang Zidong; Liang Jinling

    2008-01-01

    In this Letter, the synchronization problem is investigated for a class of stochastic complex networks with time delays. By utilizing a new Lyapunov functional form based on the idea of 'delay fractioning', we employ the stochastic analysis techniques and the properties of Kronecker product to establish delay-dependent synchronization criteria that guarantee the globally asymptotically mean-square synchronization of the addressed delayed networks with stochastic disturbances. These sufficient conditions, which are formulated in terms of linear matrix inequalities (LMIs), can be solved efficiently by the LMI toolbox in Matlab. The main results are proved to be much less conservative and the conservatism could be reduced further as the number of delay fractioning gets bigger. A simulation example is exploited to demonstrate the advantage and applicability of the proposed result

  3. Classic conditioning in aged rabbits: delay, trace, and long-delay conditioning.

    Science.gov (United States)

    Solomon, P R; Groccia-Ellison, M E

    1996-06-01

    Young (0.5 years) and aged (2+, 3+, and 4+ years) rabbits underwent acquisition of the classically conditioned nictitating membrane response in a delay (500-ms conditioned stimulus [CS], 400-ms interstimulus interval [ISI]), long-delay (1,000-ms CS, 900-ms ISI), or trace (500-ms CS, 400-ms stimulus-free period) paradigm. Collapsing across age groups, there is a general tendency for animals to acquire trace conditioning more slowly than delay conditioning. Collapsing across conditioning paradigms, there is a general tendency for aged animals to acquire more slowly than younger animals. Of greater significance, however, are the age differences in the different conditioning paradigms. In the delay and long-delay paradigms, significant conditioning deficits first appeared in the 4(+)-year-old group. In the trace conditioning paradigm, significant conditioning deficits became apparent in the 2(+)-year-old animals.

  4. Modeling of delays in PKPD: classical approaches and a tutorial for delay differential equations.

    Science.gov (United States)

    Koch, Gilbert; Krzyzanski, Wojciech; Pérez-Ruixo, Juan Jose; Schropp, Johannes

    2014-08-01

    In pharmacokinetics/pharmacodynamics (PKPD) the measured response is often delayed relative to drug administration, individuals in a population have a certain lifespan until they maturate or the change of biomarkers does not immediately affects the primary endpoint. The classical approach in PKPD is to apply transit compartment models (TCM) based on ordinary differential equations to handle such delays. However, an alternative approach to deal with delays are delay differential equations (DDE). DDEs feature additional flexibility and properties, realize more complex dynamics and can complementary be used together with TCMs. We introduce several delay based PKPD models and investigate mathematical properties of general DDE based models, which serve as subunits in order to build larger PKPD models. Finally, we review current PKPD software with respect to the implementation of DDEs for PKPD analysis.

  5. Information transfer via implicit encoding with delay time modulation in a time-delay system

    Energy Technology Data Exchange (ETDEWEB)

    Kye, Won-Ho, E-mail: whkye@kipo.go.kr [Korean Intellectual Property Office, Government Complex Daejeon Building 4, 189, Cheongsa-ro, Seo-gu, Daejeon 302-701 (Korea, Republic of)

    2012-08-20

    A new encoding scheme for information transfer with modulated delay time in a time-delay system is proposed. In the scheme, the message is implicitly encoded into the modulated delay time. The information transfer rate as a function of encoding redundancy in various noise scales is presented and it is analyzed that the implicit encoding scheme (IES) has stronger resistance against channel noise than the explicit encoding scheme (EES). In addition, its advantages in terms of secure communication and feasible applications are discussed. -- Highlights: ► We propose new encoding scheme with delay time modulation. ► The message is implicitly encoded with modulated delay time. ► The proposed scheme shows stronger resistance against channel noise.

  6. Delayed minocycline but not delayed mild hypothermia protects against embolic stroke

    Directory of Open Access Journals (Sweden)

    Noor Raza

    2002-04-01

    Full Text Available Abstract Background Inflammatory reactions occurring in the brain after ischemia may contribute to secondary damage. In the present study, effects of minocycline, an anti-inflammatory agent, alone or in combination with mild hypothermia on focal embolic cerebral ischemia have been examined. Methods Focal ischemic injury was induced by embolizing a preformed clot into the middle cerebral artery (MCA. Infarction volume was measured at 48 h after the injury. Mortality was also recorded. Results Delayed administration of minocycline alone or delayed minocycline plus delayed mild hypothermia reduced the infarction volume significantly. However, delayed mild hypothermia alone was not protective and delayed mild hypothermia in combination with minocycline did not show any additive effect. Conclusions These results suggest that minocycline is beneficial in focal ischemic brain injury, and the lack of the enhanced neuroprotection may be due to the brief exposure to hypothermia.

  7. Atmospheric Phase Delay in Sentinel SAR Interferometry

    Science.gov (United States)

    Krishnakumar, V.; Monserrat, O.; Crosetto, M.; Crippa, B.

    2018-04-01

    The repeat-pass Synthetic Aperture Radio Detection and Ranging (RADAR) Interferometry (InSAR) has been a widely used geodetic technique for observing the Earth's surface, especially for mapping the Earth's topography and deformations. However, InSAR measurements are prone to atmospheric errors. RADAR waves traverse the Earth's atmosphere twice and experience a delay due to atmospheric refraction. The two major layers of the atmosphere (troposphere and ionosphere) are mainly responsible for this delay in the propagating RADAR wave. Previous studies have shown that water vapour and clouds present in the troposphere and the Total Electron Content (TEC) of the ionosphere are responsible for the additional path delay in the RADAR wave. The tropospheric refractivity is mainly dependent on pressure, temperature and partial pressure of water vapour. The tropospheric refractivity leads to an increase in the observed range. These induced propagation delays affect the quality of phase measurement and introduce errors in the topography and deformation fields. The effect of this delay was studied on a differential interferogram (DInSAR). To calculate the amount of tropospheric delay occurred, the meteorological data collected from the Spanish Agencia Estatal de Meteorología (AEMET) and MODIS were used. The interferograms generated from Sentinel-1 carrying C-band Synthetic Aperture RADAR Single Look Complex (SLC) images acquired on the study area are used. The study area consists of different types of scatterers exhibiting different coherence. The existing Saastamoinen model was used to perform a quantitative evaluation of the phase changes caused by pressure, temperature and humidity of the troposphere during the study. Unless the phase values due to atmospheric disturbances are not corrected, it is difficult to obtain accurate measurements. Thus, the atmospheric error correction is essential for all practical applications of DInSAR to avoid inaccurate height and deformation

  8. ATMOSPHERIC PHASE DELAY IN SENTINEL SAR INTERFEROMETRY

    Directory of Open Access Journals (Sweden)

    V. Krishnakumar

    2018-04-01

    Full Text Available The repeat-pass Synthetic Aperture Radio Detection and Ranging (RADAR Interferometry (InSAR has been a widely used geodetic technique for observing the Earth’s surface, especially for mapping the Earth’s topography and deformations. However, InSAR measurements are prone to atmospheric errors. RADAR waves traverse the Earth’s atmosphere twice and experience a delay due to atmospheric refraction. The two major layers of the atmosphere (troposphere and ionosphere are mainly responsible for this delay in the propagating RADAR wave. Previous studies have shown that water vapour and clouds present in the troposphere and the Total Electron Content (TEC of the ionosphere are responsible for the additional path delay in the RADAR wave. The tropospheric refractivity is mainly dependent on pressure, temperature and partial pressure of water vapour. The tropospheric refractivity leads to an increase in the observed range. These induced propagation delays affect the quality of phase measurement and introduce errors in the topography and deformation fields. The effect of this delay was studied on a differential interferogram (DInSAR. To calculate the amount of tropospheric delay occurred, the meteorological data collected from the Spanish Agencia Estatal de Meteorología (AEMET and MODIS were used. The interferograms generated from Sentinel-1 carrying C-band Synthetic Aperture RADAR Single Look Complex (SLC images acquired on the study area are used. The study area consists of different types of scatterers exhibiting different coherence. The existing Saastamoinen model was used to perform a quantitative evaluation of the phase changes caused by pressure, temperature and humidity of the troposphere during the study. Unless the phase values due to atmospheric disturbances are not corrected, it is difficult to obtain accurate measurements. Thus, the atmospheric error correction is essential for all practical applications of DInSAR to avoid inaccurate

  9. Observations on early and delayed colostomy closure.

    Science.gov (United States)

    Tade, A O; Salami, B A; Ayoade, B A

    2011-06-01

    Traditional treatment of a variety of colorectal pathologies had included a diverting colostomy that was closed eight or more weeks later during a readmission. The aim of this retrospective study was to determine the outcomes of early colostomy closure and delayed colostomy closure in patients with temporary colostomies following traumatic and non-traumatic colorectal pathologies. In this study early colostomy closure was the closure of a colostomy within three weeks of its construction, while delayed colostomy closure referred to closure after 3 weeks. Complete records of the 37 adult patients who had temporary colostomy constructed and closed between Jan. 1997 December 2003 for various colorectal pathologies were studied. Fourteen patients had early colostomy closure while 23 had delayed closure. In the early colostomy closure group there were 10 men and 4 women. The mean age of the patients was 28yr with a range of 18-65yr. Colostomies were closed 9-18 days after initial colostomy construction. There was no mortality. Morbidity rate 28.6% (4 out of 14). There were two faecal fistulas (14.3%). Twenty-three patients had delayed colostomy closure 8 weeks to 18 months after initial colostomy construction. These were patients unfit for early surgery after initial colostomy construction because of carcinoma, significant weight loss, or sepsis. There was no mortality. Morbidity rate was 26.1%. There were 3 faecal fistulas (13.2%). Outcomes following early colostomy closure and delayed closure were comparable. Patients fit for surgery should have early closure whilst patients who may have compromised health should have delayed closure.

  10. The Strong Lensing Time Delay Challenge (2014)

    Science.gov (United States)

    Liao, Kai; Dobler, G.; Fassnacht, C. D.; Treu, T.; Marshall, P. J.; Rumbaugh, N.; Linder, E.; Hojjati, A.

    2014-01-01

    Time delays between multiple images in strong lensing systems are a powerful probe of cosmology. At the moment the application of this technique is limited by the number of lensed quasars with measured time delays. However, the number of such systems is expected to increase dramatically in the next few years. Hundred such systems are expected within this decade, while the Large Synoptic Survey Telescope (LSST) is expected to deliver of order 1000 time delays in the 2020 decade. In order to exploit this bounty of lenses we needed to make sure the time delay determination algorithms have sufficiently high precision and accuracy. As a first step to test current algorithms and identify potential areas for improvement we have started a "Time Delay Challenge" (TDC). An "evil" team has created realistic simulated light curves, to be analyzed blindly by "good" teams. The challenge is open to all interested parties. The initial challenge consists of two steps (TDC0 and TDC1). TDC0 consists of a small number of datasets to be used as a training template. The non-mandatory deadline is December 1 2013. The "good" teams that complete TDC0 will be given access to TDC1. TDC1 consists of thousands of lightcurves, a number sufficient to test precision and accuracy at the subpercent level, necessary for time-delay cosmography. The deadline for responding to TDC1 is July 1 2014. Submissions will be analyzed and compared in terms of predefined metrics to establish the goodness-of-fit, efficiency, precision and accuracy of current algorithms. This poster describes the challenge in detail and gives instructions for participation.

  11. The delayed neutron method of uranium analysis

    International Nuclear Information System (INIS)

    Wall, T.

    1989-01-01

    The technique of delayed neutron analysis (DNA) is discussed. The DNA rig installed on the MOATA reactor, the assay standards and the types of samples which have been assayed are described. Of the total sample throughput of about 55,000 units since the uranium analysis service began, some 78% has been concerned with analysis of uranium ore samples derived from mining and exploration. Delayed neutron analysis provides a high sensitivity, low cost uranium analysis method for both uranium exploration and other applications. It is particularly suitable for analysis of large batch samples and for non-destructive analysis over a wide range of matrices. 8 refs., 4 figs., 3 tabs

  12. Time-delay analyzer with continuous discretization

    International Nuclear Information System (INIS)

    Bayatyan, G.L.; Darbinyan, K.T.; Mkrtchyan, K.K.; Stepanyan, S.S.

    1988-01-01

    A time-delay analyzer is described which when triggered by a start pulse of adjustable duration performs continuous discretization of the analyzed signal within nearly 22 ns time intervals, the recording in a memory unit with following slow read-out of the information to the computer and its processing. The time-delay analyzer consists of four CAMAC-VECTOR systems of unit width. With its help one can separate comparatively short, small-amplitude rare signals against the background of quasistationary noise processes. 4 refs.; 3 figs

  13. Permanent molars: Delayed development and eruption

    Directory of Open Access Journals (Sweden)

    Arathi R

    2006-05-01

    Full Text Available Delayed development and eruption of all the permanent molars is a rare phenomenon, which can cause disturbance in the developing occlusion. The eruption of permanent first and second molars is very important for the coordination of facial growth and for providing sufficient occlusal support for undisturbed mastication. In the case described, the first permanent molars were delayed in their development and were seen erupting at the age of nine and a half years. Severe disparity between the left and the right side of the dentition with respect to the rate of development of molars were also present.

  14. Management of delayed nuclear power plant projects

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-09-01

    According to the available information at the IAEA PRIS (Power Reactor Information System) at the end of 1998 there were more than 40 nuclear power plant projects with delays of five or more years with respect to the originally scheduled commercial operation. The degree of conformance with original construction schedules showed large variations due to several issues, including financial, economic and public opinion factors. Taking into account the number of projects with several years delay in their original schedules, it was considered useful to identify the subject areas where exchange of experience among Member States would be mutually beneficial in identification of problems and development of guidance for successful management of the completion of these delayed projects. A joint programme of the IAEA Departments of Nuclear Energy (Nuclear Power Engineering Section) and Technical Co-operation (Europe Section, with additional support from the Latin America and West Asia Sections) was set up during the period 1997-1998. The specific aim of the programme was to provide assistance in the management of delayed nuclear power plants regarding measures to maintain readiness for resuming the project implementation schedule when the conditions permit. The integration of IAEA interdepartmental resources enabled the participation of 53 experts from 14 Member States resulting in a wider exchange of experience and dissemination of guidance. Under the framework of the joint programme, senior managers directly responsible for delayed nuclear power plant projects identified several issues or problem areas that needed to be addressed and guidance on management be provided. A work plan for the development of several working documents, addressing the different issues, was established. Subsequently these documents were merged into a single one to produce the present publication. This publication provides information and practical examples on necessary management actions to preserve

  15. Management of delayed nuclear power plant projects

    International Nuclear Information System (INIS)

    1999-09-01

    According to the available information at the IAEA PRIS (Power Reactor Information System) at the end of 1998 there were more than 40 nuclear power plant projects with delays of five or more years with respect to the originally scheduled commercial operation. The degree of conformance with original construction schedules showed large variations due to several issues, including financial, economic and public opinion factors. Taking into account the number of projects with several years delay in their original schedules, it was considered useful to identify the subject areas where exchange of experience among Member States would be mutually beneficial in identification of problems and development of guidance for successful management of the completion of these delayed projects. A joint programme of the IAEA Departments of Nuclear Energy (Nuclear Power Engineering Section) and Technical Co-operation (Europe Section, with additional support from the Latin America and West Asia Sections) was set up during the period 1997-1998. The specific aim of the programme was to provide assistance in the management of delayed nuclear power plants regarding measures to maintain readiness for resuming the project implementation schedule when the conditions permit. The integration of IAEA interdepartmental resources enabled the participation of 53 experts from 14 Member States resulting in a wider exchange of experience and dissemination of guidance. Under the framework of the joint programme, senior managers directly responsible for delayed nuclear power plant projects identified several issues or problem areas that needed to be addressed and guidance on management be provided. A work plan for the development of several working documents, addressing the different issues, was established. Subsequently these documents were merged into a single one to produce the present publication. This publication provides information and practical examples on necessary management actions to preserve

  16. The Consequences of Delaying Entrance into University

    DEFF Research Database (Denmark)

    Foley, Kelly; Groes, Fane

    Because the returns to education depend on the nite horizon of individuals' working lives, human capital models predict that if an individual is going to attend university, she should do so as soon as possible. Delaying university can also mean individuals have fewer years in which to accumulate...... post-schooling experience. In this paper, we use Danish administrative data to estimate the wage losses experienced by individuals who accumulate less post-schooling experience because they postponed entry into university following high school. All else equal, experience-related costs of delaying...

  17. Double Hopf bifurcation in delay differential equations

    Directory of Open Access Journals (Sweden)

    Redouane Qesmi

    2014-07-01

    Full Text Available The paper addresses the computation of elements of double Hopf bifurcation for retarded functional differential equations (FDEs with parameters. We present an efficient method for computing, simultaneously, the coefficients of center manifolds and normal forms, in terms of the original FDEs, associated with the double Hopf singularity up to an arbitrary order. Finally, we apply our results to a nonlinear model with periodic delay. This shows the applicability of the methodology in the study of delay models arising in either natural or technological problems.

  18. 4-channel time delayed pulse generator

    International Nuclear Information System (INIS)

    Wetzel, L.F.S.; Rossi, J.O.; Del Bosco, E.

    1987-02-01

    It is described the project of a 4-channel delayed pulse generator employed to trigger the plasma centrifuge experiment of the Laboratorio Associado de Plasmas. The circuit delivers pulses with amplitude of 15V, full width at half maximum of 50μs and rise time of 0.7μs. The maximum time delay is 100ms. There are two channels with a fine adjustment of 0-1ms. The system can be manually or automatically driven. (author) [pt

  19. Diagnosis delay in Libyan female breast cancer.

    Science.gov (United States)

    Ermiah, Eramah; Abdalla, Fathi; Buhmeida, Abdelbaset; Larbesh, Entesar; Pyrhönen, Seppo; Collan, Yrjö

    2012-08-21

    To study the diagnosis delay and its impact on stage of disease among women with breast cancer on Libya. 200 women, aged 22 to 75 years with breast cancer diagnosed during 2008-2009 were interviewed about the period from the first symptoms to the final histological diagnosis of breast cancer. This period (diagnosis time) was categorized into 3 periods: 6 months. If diagnosis time was longer than 3 months, the diagnosis was considered delayed (diagnosis delay). Consultation time was the time taken to visit the general practitioner after the first symptoms. Retrospective preclinical and clinical data were collected on a form (questionnaire) during an interview with each patient and from medical records. The median of diagnosis time was 7.5 months. Only 30.0% of patients were diagnosed within 3 months after symptoms. 14% of patients were diagnosed within 3-6 months and 56% within a period longer than 6 months. A number of factors predicted diagnosis delay: Symptoms were not considered serious in 27% of patients. Alternative therapy (therapy not associated with cancer) was applied in 13.0% of the patients. Fear and shame prevented the visit to the doctor in 10% and 4.5% of patients, respectively. Inappropriate reassurance that the lump was benign was an important reason for prolongation of the diagnosis time. Diagnosis delay was associated with initial breast symptom(s) that did not include a lump (p diagnosis, the clinical stage distribution was as follows: 9.0% stage I, 25.5% stage II, 54.0% stage III and 11.5% stage IV.Diagnosis delay was associated with bigger tumour size (p Diagnosis delay is very serious problem in Libya. Diagnosis delay was associated with complex interactions between several factors and with advanced stages. There is a need for improving breast cancer awareness and training of general practitioners to reduce breast cancer mortality by promoting early detection. The treatment guidelines should pay more attention to the early phases of breast

  20. Delayed dermal burns caused by dimethyl acetylenedicarboxylate

    Energy Technology Data Exchange (ETDEWEB)

    Slovak, A J; Payne, A R

    1984-07-01

    A chemical operator handling dimethyl acetylenedicarboxylate (DMAD) developed delayed and pain-free burns on one of his feet 2 days after a supposed spillage of DMAD. The injuries were confirmed to be associated with DMAD by chemical analysis of the operator's safety boot and patch tests. DMAD easily penetrates some protective clothing and dilute solutions can still be hazardous: the toxic effect is compounded by being delayed and painless. The lachrymatory irritant properties of undiluted DMAD are not adequate warning of its presence or spillage in quantities sufficient to cause significant skin damage.

  1. Causal Analysis of Railway Running Delays

    DEFF Research Database (Denmark)

    Cerreto, Fabrizio; Nielsen, Otto Anker; Harrod, Steven

    Operating delays and network propagation are inherent characteristics of railway operations. These are traditionally reduced by provision of time supplements or “slack” in railway timetables and operating plans. Supplement allocation policies must trade off reliability in the service commitments...... Denmark (the Danish infrastructure manager). The statistical analysis of the data identifies the minimum running times and the scheduled running time supplements and investigates the evolution of train delays along given train paths. An improved allocation of time supplements would result in smaller...

  2. Congenital rubella syndrome and delayed manifestations

    DEFF Research Database (Denmark)

    Dammeyer, Jesper Herup

    2010-01-01

    Objective: Several hypotheses of different medical and psychological delayed manifestations among people who have congenital rubella syndrome (CRS) have been discussed. This study tests some of these hypotheses of delayed manifestations. Methods: Gathering information about 35 individuals who hav...... which people with CRS face must primarily be understood in relation to congenital deafblindness and dual sensory and communicative deprivation....... CRS and who are congenitally deafblind. Results: None of the hypotheses could be confirmed when individuals with CRS were compared to a control group of individuals who were congenital deafblind with different aetiology than CRS. Conclusions: This study concludes that those health related problems...

  3. Delayed expression of SAGs correlates with longevity in CMS wheat plants compared to its fertile plants.

    Science.gov (United States)

    Semwal, Vimal Kumar; Singh, Bhupinder; Khanna-Chopra, Renu

    2014-04-01

    Reproductive sinks regulate monocarpic senescence in crop plants. Monocarpic senescence was studied in wheat fertile (cv. HW 2041) and its isonuclear cytoplasmic male sterile (CMS) line. CMS plants exhibited slower rate of senescence accompanied by longer green leaf area duration and slower deceleration in chlorophyll, protein content, PN and rubisco content coupled with lower protease activities than fertile (F) plants. CMS plants also exhibited lower ROS levels and less membrane damage than F plants. CMS plants maintained better antioxidant defense, less oxidative damage in chloroplast and higher transcript levels of both rbcL and rbcS genes during senescence than F plants. F plants exhibited early induction and higher expression of SAGs like serine and cysteine proteases, glutamine synthetases GS1 and GS2, WRKY53 transcription factor and decline in transcript levels of CAT1 and CAT2 genes than CMS plants. Hence, using genetically fertile and its CMS line of wheat it is confirmed that delayed senescence in the absence of reproductive sinks is linked with slower protein oxidation, rubisco degradation and delayed activation of SAGs. Better antioxidant defense in chloroplasts at later stages of senescence was able to mitigate the deleterious effects of ROS in CMS plants. We propose that delayed increase in ROS in cytoplasmic male sterile wheat plants resulted in delayed activation of WRKY53, SAGs and the associated biochemical changes than fertile plants.

  4. Simulation of activation and propagation delay during tripolar neural stimulation

    NARCIS (Netherlands)

    Goodall, E.V.; Goodall, Eleanor V.; Kosterman, L. Martin; Struijk, Johannes J.; Struijk, J.J.; Holsheimer, J.

    1993-01-01

    Computer simulations were perfonned to investigate the influence of stimulus amplitude on cathodal activation delay, propagation delay and blocking during stimulation with a bipolar cuff electrode. Activation and propagation delays were combined in a total delay term which was minimized between the

  5. Deflection system of a high-speed streak camera in the form of a delay line

    International Nuclear Information System (INIS)

    Korzhenevich, I.M.; Fel'dman, G.G.

    1993-01-01

    This paper presents an analysis of the operation of a meander deflection system, well-known in oscillography, when it is used to scan the image in a streak-camera tube. Effects that are specific to high-speed photography are considered. It is shown that such a deflection system imposes reduced requirements both on the steepness and on the duration of the linear leading edges of the pulses of the spark gaps that generate the sweep voltage. An example of the design of a meander deflection system whose sensitivity is a factor of two higher than for a conventional system is considered. 5 refs., 3 figs

  6. Veterans Crisis Line

    Data.gov (United States)

    Department of Veterans Affairs — The caring responders at the Veterans Crisis Line are specially trained and experienced in helping Veterans of all ages and circumstances. Some of the responders are...

  7. Product line design

    Czech Academy of Sciences Publication Activity Database

    Anderson, S. P.; Celik, Levent

    2015-01-01

    Roč. 157, May (2015), s. 517-526 ISSN 0022-0531 Institutional support: RVO:67985998 Keywords : product line design * product differentiation * second-degree price discrimination Subject RIV: AH - Economics Impact factor: 1.097, year: 2015

  8. Kansas Electric Transmission Lines

    Data.gov (United States)

    Kansas Data Access and Support Center — This data set is a digital representation of the EletcircTransmission lines for the State of Kansas as maintained by the Kansas Corporation Commission. Data is...

  9. Electric Power Transmission Lines

    Data.gov (United States)

    Department of Homeland Security — Transmission Lines are the system of structures, wires, insulators and associated hardware that carry electric energy from one point to another in an electric power...

  10. SAF line powder operations

    International Nuclear Information System (INIS)

    Frederickson, J.R.; Horgos, R.M.

    1983-10-01

    An automated nuclear fuel fabrication line is being designed for installation in the Fuels and Materials Examination Facility (FMEF) near Richland, Washington. The fabrication line will consist of seven major process systems: Receiving and Powder Preparation; Powder Conditioning; Pressing and Boat Loading; Debinding, Sintering, and Property Adjustment; Boat Transport; Pellet Inspection and Finishing; and Pin Operations. Fuel powder processing through pellet pressing will be discussed in this paper

  11. Capital Improvements Business Line

    Science.gov (United States)

    2012-08-08

    NAVFAC Southwest Dan Waid Program & Business Mgmt NAVFAC SW Capital Improvements Business Line NAVFAC SW 8 August 2012 1 Report...REPORT TYPE 3. DATES COVERED 00-00-2012 to 00-00-2012 4. TITLE AND SUBTITLE Capital Improvements Business Line 5a. CONTRACT NUMBER 5b. GRANT...AVAILABILITY STATEMENT Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES Presented at the 2012 Navy Gold Coast Small Business

  12. Nasca Lines, Peru

    Science.gov (United States)

    2001-01-01

    The Nasca Lines are located in the Pampa region of Peru, the desolate plain of the Peruvian coast 400 km south of Lima. The Lines were first spotted when commercial airlines began flying across the Peruvian desert in the 1920's. Passengers reported seeing 'primitive landing strips' on the ground below. The Lines were made by removing the iron-oxide coated pebbles which cover the surface of the desert. When the gravel is removed, they contrast with the light color underneath. In this way the lines were drawn as furrows of a lighter color. On the pampa, south of the Nasca Lines, archaeologists have now uncovered the lost city of the line-builders, Cahuachi. It was built nearly two thousand years ago and was mysteriously abandoned 500 years later. This ASTER sub-image covers an area of 14 x 18 km, was acquired on December 22, 2000, and is located at 14.7 degrees south latitude and 75.1 degrees west longitude. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  13. Study of Relationship Between Illness Perception and Delay in Seeking Help for Breast Cancer Patients Based on Leventhal's Self-Regulation Model.

    Science.gov (United States)

    Attari, Seyedeh Maryam; Ozgoli, Giti; Solhi, Mahnaz; Alavi Majd, Hamid

    2016-01-01

    One of the major causes of morbidity and mortality in breast cancer patients is delay in seeking help. Leventhal's self-regulation model provides an appropriate framework to assess delay in seeking help. The aim of this study was to investigate the relationship between "illness perception" and "help seeking delay" in breast cancer patients based on Leventhal's self-regulation model. In this correlational descriptive study with convenience sampling conducted in 2013, participants were 120 women with breast cancer who were diagnosed in the last year and referred to chemotherapy and radiotherapy centers in Rasht, Iran. Data collection scales included demographic data, Revised Illness Perception Questionnaire (IPQ-R)and a researcher made questionnaire to measure the delay in seeking help. Pre-hospital delay (help seeking delay) was evaluated in 3 phases (assessment, disease, behavior). The data were analyzed using SPSS-19. The mean (SD) age calculated for the patients was 47.3±10.2. Some 43% of the patients had a high school or higher education level and 82% were married. The "pre-hospital delay" was reported ≥3 months. Logistic regression analysis showed that none of the illness perception components were correlated with appraisal and behavioral delay phases. In the illness delay phase, "time line" (p-value =0.04) and "risk factors"(p-value=0.03) had significant effects on reducing and "psychological attributions" had significant effects on increasing the delay (p-value =0.01). "Illness coherence" was correlated with decreased pre-hospital patient delay (p-valueperceptions of breast cancer influences delay in seeking help. In addition to verifying the validity of Leventhal's self-regulation model in explaining delay in seeking help, the results signify the importance of the "illness delay phase" (decision to seek help) and educational interventions-counseling for women in the community.

  14. Galactic Shapiro delay to the Crab pulsar and limit on weak equivalence principle violation

    International Nuclear Information System (INIS)

    Desai, Shantanu; Kahya, Emre

    2018-01-01

    We calculate the total galactic Shapiro delay to the Crab pulsar by including the contributions from the dark matter as well as baryonic matter along the line of sight. The total delay due to dark matter potential is about 3.4 days. For baryonic matter, we included the contributions from both the bulge and the disk, which are approximately 0.12 and 0.32 days respectively. The total delay from all the matter distribution is therefore 3.84 days. We also calculate the limit on violations of Weak equivalence principle by using observations of ''nano-shot'' giant pulses from the Crab pulsar with time-delay < 0.4 ns, as well as using time differences between radio and optical photons observed from this pulsar. Using the former, we obtain a limit on violation of Weak equivalence principle in terms of the PPN parameter Δγ < 2.41 x 10 -15 . From the time-difference between simultaneous optical and radio observations, we get Δγ < 1.54 x 10 -9 . We also point out differences in our calculation of Shapiro delay and that from two recent papers (Yang and Zhang, Phys Rev D 94(10):101501, 2016; Zhang and Gong, Astrophys J 837:134, 2017), which used the same observations to obtain a corresponding limit on Δγ. (orig.)

  15. Galactic Shapiro delay to the Crab pulsar and limit on weak equivalence principle violation

    Energy Technology Data Exchange (ETDEWEB)

    Desai, Shantanu [Indian Institute of Technology, Department of Physics, Hyderabad, Telangana (India); Kahya, Emre [Istanbul Technical University, Department of Physics, Istanbul (Turkey)

    2018-02-15

    We calculate the total galactic Shapiro delay to the Crab pulsar by including the contributions from the dark matter as well as baryonic matter along the line of sight. The total delay due to dark matter potential is about 3.4 days. For baryonic matter, we included the contributions from both the bulge and the disk, which are approximately 0.12 and 0.32 days respectively. The total delay from all the matter distribution is therefore 3.84 days. We also calculate the limit on violations of Weak equivalence principle by using observations of ''nano-shot'' giant pulses from the Crab pulsar with time-delay < 0.4 ns, as well as using time differences between radio and optical photons observed from this pulsar. Using the former, we obtain a limit on violation of Weak equivalence principle in terms of the PPN parameter Δγ < 2.41 x 10{sup -15}. From the time-difference between simultaneous optical and radio observations, we get Δγ < 1.54 x 10{sup -9}. We also point out differences in our calculation of Shapiro delay and that from two recent papers (Yang and Zhang, Phys Rev D 94(10):101501, 2016; Zhang and Gong, Astrophys J 837:134, 2017), which used the same observations to obtain a corresponding limit on Δγ. (orig.)

  16. Delay in seeking care for tuberculosis symptoms among adults newly diagnosed with HIV in rural Malawi.

    Science.gov (United States)

    Ngwira, L G; Dowdy, D W; Khundi, M; Barnes, G L; Nkhoma, A; Choko, A T; Murowa, M; Chaisson, R E; Corbett, E L; Fielding, K

    2018-03-01

    Ten primary health clinics in rural Thyolo District, Malawi. Tuberculosis (TB) is a common initial presentation of human immunodeficiency virus (HIV) infection. We investigated the time from TB symptom onset to HIV diagnosis to describe TB health-seeking behaviour in adults newly diagnosed with HIV. We asked adults (18 years) about the presence and duration of TB symptoms at the time of receiving a new HIV diagnosis. Associations with delayed health seeking (defined as >30 and >90 days from the onset of TB symptoms) were evaluated using multivariable logistic regression. TB symptoms were reported by 416 of 1265 participants (33%), of whom 36% (150/416) had been symptomatic for >30 days before HIV testing. Most participants (260/416, 63%) were below the poverty line (US$0.41 per household member per day). Patients who first sought care from informal providers had an increased odds of delay of >30 days (adjusted odds ratio [aOR] 1.6, 95%CI 0.9-2.8) or 90 days (aOR 2.0, 95%CI 1.1-3.8). Delayed health seeking for TB-related symptoms was common. Poverty was ubiquitous, but had no clear relationship to diagnostic delay. HIV-positive individuals who first sought care from informal providers were more likely to experience diagnostic delays for TB symptoms.

  17. Influence of the circadian rhythm in cell division on radiation-induced mitotic delay in vivo

    International Nuclear Information System (INIS)

    Rubin, N.A.

    1980-01-01

    All mitotically active normal tissues in mammals investigated to date demonstrate a circadian rhythm in cell division. The murine corneal epithelium is a practical and advantageous tissue model for studying this phenomenon. In animals synchronized to a light-dark (LD) schedule, one sees predictably reproducible occurrences of peaks and troughs in the mitotic index (MI) within each 24-hour (h) period. One of the harmful effects of ionizing radiation on dividing cells is mitotic delay, reported to be a G 2 block in cells approaching mitosis. Affected cells are not killed but are inhibited from entering mitosis and are delayed for a span of time reported to be dose and cell cycle dependent. In the classical description of mitotic delay, MI of irradiated cells begins to drop in relation to the control, which is plotted as a straight line, uniform throughout the experiment. After the damage is repaired, delayed cells can enter mitosis along with other cells in the pool unaffected by the radiation, resulting in a MI higher than control levels. The span of delay and the occurrence of recovery are assumed to be constant for a given dose and tissue under similar experimental conditions. First described in asynchronously-dividing tissue culture cells, this concept is also extrapolated to the in vivo situation

  18. Delay Tolerance: A Therapeutic Possibility for AD/HD?

    Directory of Open Access Journals (Sweden)

    Edmund J. S. Sonuga-Barke

    2004-01-01

    on these two insights to explore the possibility that the motivational alterations underpinning delay aversion can be modified through specific training regimes in a way equivalent to that found with executive and attentional training. The requirements for such an approach are set out. Delay fading is proposed as a possible basis for reorganizing delay experience, altering the incentive value of delay (e.g., increasing tolerance for delay, thereby reducing AD/HD symptoms.

  19. ATFM airborne delays without extra fuel consumption in wind conditions

    OpenAIRE

    Delgado, L.; Prats, X.

    2012-01-01

    Air Traffic Flow Management (ATFM) regulations, such as ground holdings, are often canceled before their initially planned ending time. The ground delays impact on the cost of recovering part of the delay if the regulation is canceled, as aircraft are still at the origin airport. In previous publications, the authors have suggested a speed reduction strategy to split the assigned ATFM delay between ground delay and airborne delay. By flying at the the minimum speed that g...

  20. Selective induction of cyclin B protein abrogates the G2 delay after irradiation

    International Nuclear Information System (INIS)

    Kao, G.; Muschel, R.J.; Maity, A.; Kunig, A.; McKenna, W.G.

    1996-01-01

    Purpose/Objective: Irradiation of tumor cells commonly results in G2 delay, which has been postulated to allow DNA repair and cell survival. The G2 delay after irradiation is also often marked in some cell lines by delayed expression of cyclin B protein, suggesting a role for cyclin B regulation. Investigations of these hypotheses however has been hampered by the inability to selectively perturb the G2 delay in a physiologic manner. Materials and Methods: We have devised a system, with which we are able to selectively induce cyclin B protein expression in vivo at specific points in the cell cycle, by transfecting Hela cells with an expression vector under control of a dexamethasone-inducible promoter. Experiments were subsequently performed by synchronizing, releasing, irradiating, inducing, and harvesting these cells through the cell cycle. Results: Irradiation with 5 Gy led to a pronounced G2 delay, reflected by markedly slowed progression into mitosis, concomitant with reduced expression of cyclin B protein. Induction of cyclin B after radiation in these cells abrogated the G2 delay by approximately doubling the rate at which the cells re-enter mitosis. Treatment of irradiated untransfected control cells with dexamethasone, in which cyclin B is not induced, led to minimal changes. Studies of effects of cyclin B induction on cyclin B localization (using immunofluorescence), cdc2 phosphorylation and activation will also be presented. Conclusion: This system should allow further investigations into fundamental mechanisms of cell cycle regulation after irradiation and DNA damage. This also provides direct evidence for the first time that cyclin B protein regulation may play a role in the G2 delay following irradiation in Hela cells, perhaps complementing phosphorylation events

  1. The Effect of Concurrent Semantic Categorization on Delayed Serial Recall

    Science.gov (United States)

    Acheson, Daniel J.; MacDonald, Maryellen C.; Postle, Bradley R.

    2010-01-01

    The influence of semantic processing on the serial ordering of items in short-term memory was explored using a novel dual-task paradigm. Subjects engaged in two picture judgment tasks while simultaneously performing delayed serial recall. List material varied in the presence of phonological overlap (Experiments 1 and 2) and in semantic content (concrete words in Experiment 1 and 3; nonwords in Experiments 2 and 3). Picture judgments varied in the extent to which they required accessing visual semantic information (i.e., semantic categorization and line orientation judgments). Results showed that, relative to line orientation judgments, engaging in semantic categorization judgments increased the proportion of item ordering errors for concrete lists but did not affect error proportions for nonword lists. Furthermore, although more ordering errors were observed for phonologically similar relative to dissimilar lists, no interactions were observed between the phonological overlap and picture judgment task manipulations. These results thus demonstrate that lexical-semantic representations can affect the serial ordering of items in short-term memory. Furthermore, the dual-task paradigm provides a new method for examining when and how semantic representations affect memory performance. PMID:21058880

  2. Performance Evaluation of Blind Tropospheric Delay correction ...

    African Journals Online (AJOL)

    lekky

    and Temperature 2 wet (GPT2w) models) for tropospheric delay correction, ... In practice, a user often employs a certain troposphere model based on the popularity ... comparisons between some of the models have been carried out in the past for .... prediction of meteorological parameter values, which are then used to ...

  3. STEMI time delays: A clinical perspective

    NARCIS (Netherlands)

    M.J. de Boer (Menko Jan); F. Zijlstra (Felix)

    2015-01-01

    textabstractSTEMI time delays have been introduced as a performance indicator or marker of quality of care. As they are only one part of a very complex medical process, one should be aware of concomitant issues that may be overlooked or even be more important with regard to clinical outcome of STEMI

  4. Third order differential equations with delay

    Directory of Open Access Journals (Sweden)

    Petr Liška

    2015-05-01

    Full Text Available In this paper, we study the oscillation and asymptotic properties of solutions of certain nonlinear third order differential equations with delay. In particular, we extend results of I. Mojsej (Nonlinear Analysis 68, 2008 and we improve conditions on the property B of N. Parhi and S. Padhi (Indian J. Pure Appl. Math., 33, 2002.

  5. Radionuclide scan findings in delayed splenic rupture

    International Nuclear Information System (INIS)

    Flickinger, F.W.; Jackson, G.L.

    1978-01-01

    An initial liver/spleen scan performed on a patient with blunt abdominal trauma was negative 3 days following the accident. A follow-up scan 7 days later showed definite evidence of splenic rupture, proved surgically. The authors conclude that, in such cases, spleen scans may be negative initially because of delayed splenic ruptures

  6. Photoemission and photoionization time delays and rates

    Science.gov (United States)

    Gallmann, L.; Jordan, I.; Wörner, H. J.; Castiglioni, L.; Hengsberger, M.; Osterwalder, J.; Arrell, C. A.; Chergui, M.; Liberatore, E.; Rothlisberger, U.; Keller, U.

    2017-01-01

    Ionization and, in particular, ionization through the interaction with light play an important role in fundamental processes in physics, chemistry, and biology. In recent years, we have seen tremendous advances in our ability to measure the dynamics of photo-induced ionization in various systems in the gas, liquid, or solid phase. In this review, we will define the parameters used for quantifying these dynamics. We give a brief overview of some of the most important ionization processes and how to resolve the associated time delays and rates. With regard to time delays, we ask the question: how long does it take to remove an electron from an atom, molecule, or solid? With regard to rates, we ask the question: how many electrons are emitted in a given unit of time? We present state-of-the-art results on ionization and photoemission time delays and rates. Our review starts with the simplest physical systems: the attosecond dynamics of single-photon and tunnel ionization of atoms in the gas phase. We then extend the discussion to molecular gases and ionization of liquid targets. Finally, we present the measurements of ionization delays in femto- and attosecond photoemission from the solid–vacuum interface. PMID:29308414

  7. Photoemission and photoionization time delays and rates

    Directory of Open Access Journals (Sweden)

    L. Gallmann

    2017-11-01

    Full Text Available Ionization and, in particular, ionization through the interaction with light play an important role in fundamental processes in physics, chemistry, and biology. In recent years, we have seen tremendous advances in our ability to measure the dynamics of photo-induced ionization in various systems in the gas, liquid, or solid phase. In this review, we will define the parameters used for quantifying these dynamics. We give a brief overview of some of the most important ionization processes and how to resolve the associated time delays and rates. With regard to time delays, we ask the question: how long does it take to remove an electron from an atom, molecule, or solid? With regard to rates, we ask the question: how many electrons are emitted in a given unit of time? We present state-of-the-art results on ionization and photoemission time delays and rates. Our review starts with the simplest physical systems: the attosecond dynamics of single-photon and tunnel ionization of atoms in the gas phase. We then extend the discussion to molecular gases and ionization of liquid targets. Finally, we present the measurements of ionization delays in femto- and attosecond photoemission from the solid–vacuum interface.

  8. Tuberculous Lymphadenitis: Skin Delayed-Type Hypersensitivity ...

    African Journals Online (AJOL)

    Tuberculous Lymphadenitis: Skin Delayed-Type Hypersensitivity Reaction and Cellular Immune Responses. ... The tuberculin skin test (TST) and peripheral blood mono-nuclear cells (PBMCs) culture were conducted using PPD. The cytokines were measured using commercial kits. Results: The mean TST was 24.6 ±8.0 ...

  9. Delay differential systems for tick population dynamics.

    Science.gov (United States)

    Fan, Guihong; Thieme, Horst R; Zhu, Huaiping

    2015-11-01

    Ticks play a critical role as vectors in the transmission and spread of Lyme disease, an emerging infectious disease which can cause severe illness in humans or animals. To understand the transmission dynamics of Lyme disease and other tick-borne diseases, it is necessary to investigate the population dynamics of ticks. Here, we formulate a system of delay differential equations which models the stage structure of the tick population. Temperature can alter the length of time delays in each developmental stage, and so the time delays can vary geographically (and seasonally which we do not consider). We define the basic reproduction number [Formula: see text] of stage structured tick populations. The tick population is uniformly persistent if [Formula: see text] and dies out if [Formula: see text]. We present sufficient conditions under which the unique positive equilibrium point is globally asymptotically stable. In general, the positive equilibrium can be unstable and the system show oscillatory behavior. These oscillations are primarily due to negative feedback within the tick system, but can be enhanced by the time delays of the different developmental stages.

  10. Moments of the Wigner delay times

    International Nuclear Information System (INIS)

    Berkolaiko, Gregory; Kuipers, Jack

    2010-01-01

    The Wigner time delay is a measure of the time spent by a particle inside the scattering region of an open system. For chaotic systems, the statistics of the individual delay times (whose average is the Wigner time delay) are thought to be well described by random matrix theory. Here we present a semiclassical derivation showing the validity of random matrix results. In order to simplify the semiclassical treatment, we express the moments of the delay times in terms of correlation functions of scattering matrices at different energies. In the semiclassical approximation, the elements of the scattering matrix are given in terms of the classical scattering trajectories, requiring one to study correlations between sets of such trajectories. We describe the structure of correlated sets of trajectories and formulate the rules for their evaluation to the leading order in inverse channel number. This allows us to derive a polynomial equation satisfied by the generating function of the moments. Along with showing the agreement of our semiclassical results with the moments predicted by random matrix theory, we infer that the scattering matrix is unitary to all orders in the semiclassical approximation.

  11. Delayed early proprioceptive information processing in schizophrenia

    DEFF Research Database (Denmark)

    Arnfred, Sidse M; Hemmingsen, RP; Parnas, Josef

    2006-01-01

    . In the patients, the early contralateral parietal activity was delayed and later central activity had increased amplitude, but gating was unaffected. The results could be understood within the "deficiency of corollary discharge" model of schizophrenia but not within the "filtering" theory. Further studies...

  12. A Delay Discounting Model of Psychotherapy Termination

    Science.gov (United States)

    Swift, Joshua K.; Callahan, Jennifer L.

    2009-01-01

    Delay discounting (DD) procedures are emerging as an important new method for psychotherapy researchers. In this paper a framework for conceptualizing existing, seemingly discrepant, research findings on termination is introduced and new directions for research are described. To illustrate the value of a DD framework, the common psychotherapy…

  13. Optimal Control for Stochastic Delay Evolution Equations

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Qingxin, E-mail: mqx@hutc.zj.cn [Huzhou University, Department of Mathematical Sciences (China); Shen, Yang, E-mail: skyshen87@gmail.com [York University, Department of Mathematics and Statistics (Canada)

    2016-08-15

    In this paper, we investigate a class of infinite-dimensional optimal control problems, where the state equation is given by a stochastic delay evolution equation with random coefficients, and the corresponding adjoint equation is given by an anticipated backward stochastic evolution equation. We first prove the continuous dependence theorems for stochastic delay evolution equations and anticipated backward stochastic evolution equations, and show the existence and uniqueness of solutions to anticipated backward stochastic evolution equations. Then we establish necessary and sufficient conditions for optimality of the control problem in the form of Pontryagin’s maximum principles. To illustrate the theoretical results, we apply stochastic maximum principles to study two examples, an infinite-dimensional linear-quadratic control problem with delay and an optimal control of a Dirichlet problem for a stochastic partial differential equation with delay. Further applications of the two examples to a Cauchy problem for a controlled linear stochastic partial differential equation and an optimal harvesting problem are also considered.

  14. Traumatic and alternating delayed intracranial hematomas

    Energy Technology Data Exchange (ETDEWEB)

    Lesoin, F.; Redford, H.; Jomin, M.; Viaud, C.; Pruvo, J.

    1984-11-01

    Repeat computed tomography has enabled us to confirm the concept of delayed hematomas. With this in mind we report two cases of alternating, post-traumatic intracranial hematomas; confirming also the role of tamponade after surgical removal of an intracranial hematoma.

  15. early versus delayed induction of labour

    African Journals Online (AJOL)

    during labour versus 18 patients (52%) in the group that was induced .... (AMG) or a delayed induction group (DIG). Sealed .... Of the 7 CSs in the DIG, 3 were for fetal heart rate .... in mind that labour was never induced later than 48 hours.

  16. Infants' Delayed Recognition Memory and Forgetting

    Science.gov (United States)

    Fagan, Joseph F., III

    1973-01-01

    Infants 21- to 25-weeks-old devoted more visual fixation to novel than familiar stimuli on immediate and delayed recognition tests. The experiments confirm the existence of long-term recognition memory for pictorial stimuli in the early months of life. (DP)

  17. Voluntary suppression of defecation delays gastric emptying

    NARCIS (Netherlands)

    Tjeerdsma, H. C.; Smout, A. J.; Akkermans, L. M.

    1993-01-01

    We wished to test the hypothesis that colonic loading with fecal material leads to delayed gastric emptying. Twelve healthy male volunteers were studied. Each of these subjects went through two randomized study periods of four days. In one of these, the subjects defecated upon urge, in the other

  18. Management of delayed nuclear power plant projects

    International Nuclear Information System (INIS)

    2005-01-01

    The IAEA assists the management of organizations responsible for Nuclear Power Plant Projects with significant delays with respect to the originally scheduled commercial operation. Several Member States have Nuclear Power Plant Projects with delays of five or more years with respect to the originally scheduled commercial operation. The degree of conformance with original construction schedules shows large variations due to several issues, including financial, economic and public opinion factors. Solving the special difficulties related with a delayed NPP project is problematic and dependent on the particular country situation. However it is not regarded as an isolated national problem but as a significant issue with a number of difficulties shared by several Member States. The IAEA collects information and supports the management of delayed NPP projects by identifying main common issues, gathering available experience and addressing specific needs. On this background the IAEA is in the position to provide unique impartial assistance based upon best international practices. This enables Member States to maintain readiness for resuming the project construction when the conditions permit and to strengthen management's abilities for the completion of the project. The IAEA's service is tailored to the needs and requirements of the requesting organization, implemented on-site by international experts and addresses areas such as project control measures, human resources, updating to technological and regulatory requirements, project data, nuclear safety review, physical protection and nuclear security and preparation to resume project construction and operation

  19. Traumatic and alternating delayed intracranial hematomas

    International Nuclear Information System (INIS)

    Lesoin, F.; Redford, H.; Jomin, M.; Viaud, C.; Pruvo, J.

    1984-01-01

    Repeat computed tomography has enabled us to confirm the concept of delayed hematomas. With this in mind we report two cases of alternating, post-traumatic intracranial hematomas; confirming also the role of tamponade after surgical removal of an intracranial hematoma. (orig.)

  20. Terrestrial Sagnac delay constraining modified gravity models

    Science.gov (United States)

    Karimov, R. Kh.; Izmailov, R. N.; Potapov, A. A.; Nandi, K. K.

    2018-04-01

    Modified gravity theories include f(R)-gravity models that are usually constrained by the cosmological evolutionary scenario. However, it has been recently shown that they can also be constrained by the signatures of accretion disk around constant Ricci curvature Kerr-f(R0) stellar sized black holes. Our aim here is to use another experimental fact, viz., the terrestrial Sagnac delay to constrain the parameters of specific f(R)-gravity prescriptions. We shall assume that a Kerr-f(R0) solution asymptotically describes Earth's weak gravity near its surface. In this spacetime, we shall study oppositely directed light beams from source/observer moving on non-geodesic and geodesic circular trajectories and calculate the time gap, when the beams re-unite. We obtain the exact time gap called Sagnac delay in both cases and expand it to show how the flat space value is corrected by the Ricci curvature, the mass and the spin of the gravitating source. Under the assumption that the magnitude of corrections are of the order of residual uncertainties in the delay measurement, we derive the allowed intervals for Ricci curvature. We conclude that the terrestrial Sagnac delay can be used to constrain the parameters of specific f(R) prescriptions. Despite using the weak field gravity near Earth's surface, it turns out that the model parameter ranges still remain the same as those obtained from the strong field accretion disk phenomenon.

  1. Maximum likelihood window for time delay estimation

    International Nuclear Information System (INIS)

    Lee, Young Sup; Yoon, Dong Jin; Kim, Chi Yup

    2004-01-01

    Time delay estimation for the detection of leak location in underground pipelines is critically important. Because the exact leak location depends upon the precision of the time delay between sensor signals due to leak noise and the speed of elastic waves, the research on the estimation of time delay has been one of the key issues in leak lovating with the time arrival difference method. In this study, an optimal Maximum Likelihood window is considered to obtain a better estimation of the time delay. This method has been proved in experiments, which can provide much clearer and more precise peaks in cross-correlation functions of leak signals. The leak location error has been less than 1 % of the distance between sensors, for example the error was not greater than 3 m for 300 m long underground pipelines. Apart from the experiment, an intensive theoretical analysis in terms of signal processing has been described. The improved leak locating with the suggested method is due to the windowing effect in frequency domain, which offers a weighting in significant frequencies.

  2. Exact, almost and delayed fault detection

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Saberi, Ali; Stoorvogel, Anton A.

    1999-01-01

    Considers the problem of fault detection and isolation while using zero or almost zero threshold. A number of different fault detection and isolation problems using exact or almost exact disturbance decoupling are formulated. Solvability conditions are given for the formulated design problems....... The l-step delayed fault detection problem is also considered for discrete-time systems....

  3. Transmission line capital costs

    International Nuclear Information System (INIS)

    Hughes, K.R.; Brown, D.R.

    1995-05-01

    The displacement or deferral of conventional AC transmission line installation is a key benefit associated with several technologies being developed with the support of the U.S. Department of Energy's Office of Energy Management (OEM). Previous benefits assessments conducted within OEM have been based on significantly different assumptions for the average cost per mile of AC transmission line. In response to this uncertainty, an investigation of transmission line capital cost data was initiated. The objective of this study was to develop a database for preparing preliminary estimates of transmission line costs. An extensive search of potential data sources identified databases maintained by the Bonneville Power Administration (BPA) and the Western Area Power Administration (WAPA) as superior sources of transmission line cost data. The BPA and WAPA data were adjusted to a common basis and combined together. The composite database covers voltage levels from 13.8 to 765 W, with cost estimates for a given voltage level varying depending on conductor size, tower material type, tower frame type, and number of circuits. Reported transmission line costs vary significantly, even for a given voltage level. This can usually be explained by variation in the design factors noted above and variation in environmental and land (right-of-way) costs, which are extremely site-specific. Cost estimates prepared from the composite database were compared to cost data collected by the Federal Energy Regulatory Commission (FERC) for investor-owned utilities from across the United States. The comparison was hampered because the only design specifications included with the FERC data were voltage level and line length. Working within this limitation, the FERC data were not found to differ significantly from the composite database. Therefore, the composite database was judged to be a reasonable proxy for estimating national average costs

  4. Exponential synchronization of two nonlinearly non-delayed and delayed coupled complex dynamical networks

    International Nuclear Information System (INIS)

    Zheng Song

    2012-01-01

    In this paper, the exponential synchronization between two nonlinearly coupled complex networks with non-delayed and delayed coupling is investigated with Lyapunov-Krasovskii-type functionals. Based on the stability analysis of the impulsive differential equation and the linear matrix inequality, sufficient delay-dependent conditions for exponential synchronization are derived, and a linear impulsive controller and simple updated laws are also designed. Furthermore, the coupling matrices need not be symmetric or irreducible. Numerical examples are presented to verify the effectiveness and correctness of the synchronization criteria obtained.

  5. Comparative study of skin blood flow in various types of delayed deltopectoral flaps using the xenon-133 clearance method

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchida, Yukihide; Ogo, Ken (Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine); Tsuya, Akira; Uchida, Masaoki; Kamata, Shinetsu; Ohura, Takehiko

    1984-07-01

    We investigated the skin blood flow in five types of delayed deltopectoral flaps and the optimal time for transfer after delay operation using the local clearance method of Xenon-133. The results obtained are reported. 1) Characteristic differences were observed in recovery patterns of the distal blood flow among the five types of delay procedure. 2) The recovery in the distal blood flow of the D-P flap lined with a split-skin graft appeared the fastest among the five types, followed by the tubed D-P flap. 3) When using a bipedicled D-P flap, lateral incision should be performed within 10 days after delay procedure. 4) The skin blood flow of less than 5 ml/100g/min indicated a high risk of necrosis of the deltopectoral flap. 5) The optimal time for transfer was found to be when the skin blood flow of the distal region recovered to the control level.

  6. Along the line

    DEFF Research Database (Denmark)

    Dinesen, Cort Ross

    2011-01-01

    Embarking on a work of art constitutes a reduction of information – because we grasp the diversity and plurality of the manifestations we encounter by abstracting them and transforming them into manageable concepts; as we do when we draw contour lines on the landscape – they are imaginary...... and invisible but an abstraction essential for noting a difference or marking a place on a map. In the same way, a stroke in a sketch or a line in the sand is a manifestation of our ability to draw a boundary that both includes and excludes information. Where the line makes the birth of an idea visible......, it expresses through movement our tendency to mark a difference by drawing attention to and enclosing a whole series of relations that confront our preconceived notions. It is in the process of transformation in which we reduce the complexity of how we work, and rethink our ideas anew by refining the very same...

  7. Spectral Line Shapes. Proceedings

    International Nuclear Information System (INIS)

    Zoppi, M.; Ulivi, L.

    1997-01-01

    These proceedings represent papers presented at the 13th International Conference on Spectral Line Shapes which was held in Firenze,Italy from June 16-21, 1996. The topics covered a wide range of subjects emphasizing the physical processes associated with the formation of line profiles: high and low density plasma; atoms and molecules in strong laser fields, Dopple-free and ultra-fine spectroscopy; the line shapes generated by the interaction of neutrals, atoms and molecules, where the relavant quantities are single particle properties, and the interaction-induced spectroscopy. There were 131 papers presented at the conference, out of these, 6 have been abstracted for the Energy Science and Technology database

  8. Stokes line width

    International Nuclear Information System (INIS)

    Nikiskov, A.I.; Ritus, V.I.

    1993-01-01

    The concept of Stokes line width is introduced for the asymptotic expansions of functions near an essential singularity. Explicit expressions are found for functions (switching functions) that switch on the exponentially small terms for the Dawson integral, Airy function, and the gamma function. A different, more natural representation of a function, not associated with expansion in an asymptotic series, in the form of dominant and recessive terms is obtained by a special division of the contour integral which represents the function into contributions of higher and lower saddle points. This division leads to a narrower, natural Stokes line width and a switching function of an argument that depends on the topology of the lines of steepest descent from the saddle point

  9. VT Digital Line Graph Railroads

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This datalayer is comprised of major railroad lines for the state of Vermont. These railroad lines line up well along quadrangle boundaries, but...

  10. Possible isomers in nuclei beyond the drip line

    International Nuclear Information System (INIS)

    Ogawa, K.

    1986-12-01

    To search a new decay model which is not observed in nuclei near stability line such as beta-delayed proton emission or direct proton emission provides us a wealth of knowledge on nuclear stability. Besides study of the nuclear decay modes, study of nuclear structures reveals us new aspect of nuclei like new deformed regions or new magic numbers. In these respects the study of a nucleus 100 Sn and its closest neighbours has a special role. (author)

  11. Design of the LINAC4 Transfer Line Quadrupole Electromagnets

    CERN Document Server

    Vanherpe, L

    2013-01-01

    Beam focusing in the various segments of the Linac4 Transfer Line is provided by quadrupole electromagnets. In total seventeen pulsed, air-cooled quadrupole electromagnets are required. They are made of laminated electrical steel yokes and coils wound from solid copper wire. All magnets have an aperture radius of 50 mm and are required to provide an integrated field gradient of 1.8 T over a magnetic length of 300 mm. This design report summarizes the main magnetic, electrical and mechanical design parameters of the Linac4 Transfer Line Quadrupole Magnets. The effect of the vacuum chamber on the magnetic field quality and the field delay is studied.

  12. Delay, doubt, and decision: how delaying a choice reduces the appeal of (descriptively) normative options.

    Science.gov (United States)

    van de Ven, Niels; Gilovich, Thomas; Zeelenberg, Marcel

    2010-04-01

    To help explain a regularity in democratic elections, we examined whether choosing to delay making a choice between a focal option and an alternative tends to make people subsequently less likely to choose what they would otherwise have chosen. The results of two experiments demonstrated that participants who were induced to delay making a decision were indeed less likely to choose the descriptively normative option. An additional experiment that primed a sense of doubt in participants provided support for a self-perception account of this result. Electing to delay making a choice is interpreted as an indication of doubt--doubt that tends to be attributed to the most prominent option. Delay-induced doubt about the normative option makes it less likely to be selected.

  13. Delay-range-dependent exponential H∞ synchronization of a class of delayed neural networks

    International Nuclear Information System (INIS)

    Karimi, Hamid Reza; Maass, Peter

    2009-01-01

    This article aims to present a multiple delayed state-feedback control design for exponential H ∞ synchronization problem of a class of delayed neural networks with multiple time-varying discrete delays. On the basis of the drive-response concept and by introducing a descriptor technique and using Lyapunov-Krasovskii functional, new delay-range-dependent sufficient conditions for exponential H ∞ synchronization of the drive-response structure of neural networks are driven in terms of linear matrix inequalities (LMIs). The explicit expression of the controller gain matrices are parameterized based on the solvability conditions such that the drive system and the response system can be exponentially synchronized. A numerical example is included to illustrate the applicability of the proposed design method.

  14. Synchronization of nonidentical chaotic neural networks with leakage delay and mixed time-varying delays

    Directory of Open Access Journals (Sweden)

    Cao Jinde

    2011-01-01

    Full Text Available Abstract In this paper, an integral sliding mode control approach is presented to investigate synchronization of nonidentical chaotic neural networks with discrete and distributed time-varying delays as well as leakage delay. By considering a proper sliding surface and constructing Lyapunov-Krasovskii functional, as well as employing a combination of the free-weighting matrix method, Newton-Leibniz formulation and inequality technique, a sliding mode controller is designed to achieve the asymptotical synchronization of the addressed nonidentical neural networks. Moreover, a sliding mode control law is also synthesized to guarantee the reachability of the specified sliding surface. The provided conditions are expressed in terms of linear matrix inequalities, and are dependent on the discrete and distributed time delays as well as leakage delay. A simulation example is given to verify the theoretical results.

  15. Adaptive modification of the delayed feedback control algorithm with a continuously varying time delay

    International Nuclear Information System (INIS)

    Pyragas, V.; Pyragas, K.

    2011-01-01

    We propose a simple adaptive delayed feedback control algorithm for stabilization of unstable periodic orbits with unknown periods. The state dependent time delay is varied continuously towards the period of controlled orbit according to a gradient-descent method realized through three simple ordinary differential equations. We demonstrate the efficiency of the algorithm with the Roessler and Mackey-Glass chaotic systems. The stability of the controlled orbits is proven by computation of the Lyapunov exponents of linearized equations. -- Highlights: → A simple adaptive modification of the delayed feedback control algorithm is proposed. → It enables the control of unstable periodic orbits with unknown periods. → The delay time is varied continuously according to a gradient descend method. → The algorithm is embodied by three simple ordinary differential equations. → The validity of the algorithm is proven by computation of the Lyapunov exponents.

  16. A distributed delay approach for modeling delayed outcomes in pharmacokinetics and pharmacodynamics studies.

    Science.gov (United States)

    Hu, Shuhua; Dunlavey, Michael; Guzy, Serge; Teuscher, Nathan

    2018-04-01

    A distributed delay approach was proposed in this paper to model delayed outcomes in pharmacokinetics and pharmacodynamics studies. This approach was shown to be general enough to incorporate a wide array of pharmacokinetic and pharmacodynamic models as special cases including transit compartment models, effect compartment models, typical absorption models (either zero-order or first-order absorption), and a number of atypical (or irregular) absorption models (e.g., parallel first-order, mixed first-order and zero-order, inverse Gaussian, and Weibull absorption models). Real-life examples were given to demonstrate how to implement distributed delays in Phoenix ® NLME™ 8.0, and to numerically show the advantages of the distributed delay approach over the traditional methods.

  17. Stochastic two-delay differential model of delayed visual feedback effects on postural dynamics.

    Science.gov (United States)

    Boulet, Jason; Balasubramaniam, Ramesh; Daffertshofer, Andreas; Longtin, André

    2010-01-28

    We report on experiments and modelling involving the 'visuo-postural control loop' in the upright stance. We experimentally manipulated an artificial delay to the visual feedback during standing, presented at delays ranging from 0 to 1 s in increments of 250 ms. Using stochastic delay differential equations, we explicitly modelled the centre-of-pressure (COP) and centre-of-mass (COM) dynamics with two independent delay terms for vision and proprioception. A novel 'drifting fixed point' hypothesis was used to describe the fluctuations of the COM with the COP being modelled as a faster, corrective process of the COM. The model was in good agreement with the data in terms of probability density functions, power spectral densities, short- and long-term correlations (Hurst exponents) as well the critical time between the two ranges. This journal is © 2010 The Royal Society

  18. Sprayed concrete linings

    Energy Technology Data Exchange (ETDEWEB)

    Hindle, D.

    1999-12-01

    Sprayed concrete, or shotcrete, was invented in the 1920s for preserving dinosaur skeletons and was used underground initially in coalmines for the preservation and fine proofing of timber supports. Its use as a support lining in rock tunnelling was developed in the 1950s and 60s. The article surveys equipment available from major manufacturers and suppliers of concrete spraying equipment (Aliva, Cifa, GIA, Industri, Ingersoll Rand, etc.), specialist cement and additive manufacturers (Castle, Cement, Moria Carbotech). manufacturers of lattice girders and fibre reinforcement, and manufacturers of instrumentation for tunnel linings. 5 tabs., 9 photos.

  19. Topology identification of the complex networks with non-delayed and delayed coupling

    International Nuclear Information System (INIS)

    Guo Wanli; Chen Shihua; Sun Wen

    2009-01-01

    In practical situation, there exists many uncertain information in complex networks, such as the topological structures. So the topology identification is an important issue in the research of the complex networks. Based on LaSalle's invariance principle, in this Letter, an adaptive controlling method is proposed to identify the topology of a weighted general complex network model with non-delayed and delayed coupling. Finally, simulation results show that the method is effective.

  20. Chaos control in delayed chaotic systems via sliding mode based delayed feedback

    Energy Technology Data Exchange (ETDEWEB)

    Vasegh, Nastaran [Faculty of Electrical Engineering, K.N. Toosi University of Technology, Seyed Khandan Bridge, Shariati St. 16314, P.O. Box 16315-1355, Tehran (Iran, Islamic Republic of)], E-mail: vasegh@eetd.kntu.ac.ir; Sedigh, Ali Khaki [Faculty of Electrical Engineering, K.N. Toosi University of Technology, Seyed Khandan Bridge, Shariati St. 16314, P.O. Box 16315-1355, Tehran (Iran, Islamic Republic of)

    2009-04-15

    This paper investigates chaos control for scalar delayed chaotic systems using sliding mode control strategy. Sliding surface design is based on delayed feedback controller. It is shown that the proposed controller can achieve stability for an arbitrary unstable fixed point (UPF) or unstable periodic orbit (UPO) with arbitrary period. The chaotic system used in this study to illustrate the theoretical concepts is the well known Mackey-Glass model. Simulation results show the effectiveness of the designed nonlinear sliding mode controller.

  1. Chaos control in delayed chaotic systems via sliding mode based delayed feedback

    International Nuclear Information System (INIS)

    Vasegh, Nastaran; Sedigh, Ali Khaki

    2009-01-01

    This paper investigates chaos control for scalar delayed chaotic systems using sliding mode control strategy. Sliding surface design is based on delayed feedback controller. It is shown that the proposed controller can achieve stability for an arbitrary unstable fixed point (UPF) or unstable periodic orbit (UPO) with arbitrary period. The chaotic system used in this study to illustrate the theoretical concepts is the well known Mackey-Glass model. Simulation results show the effectiveness of the designed nonlinear sliding mode controller.

  2. Pinning synchronization of the complex networks with non-delayed and delayed coupling

    International Nuclear Information System (INIS)

    Guo Wanli; Austin, Francis; Chen Shihua; Sun Wen

    2009-01-01

    In this Letter, without assuming the symmetry of the coupling matrix, we investigate the global synchronization of the complex networks with non-delayed and delayed coupling based on the pinning controllers. Some sufficient conditions for the global synchronization by adding linear and adaptive feedback controllers to a part of nodes are obtained. Numerical examples are also provided to demonstrate the effectiveness of the theory.

  3. Delay-Dependent Asymptotic Stability of Cohen-Grossberg Models with Multiple Time-Varying Delays

    Directory of Open Access Journals (Sweden)

    Xiaofeng Liao

    2007-01-01

    Full Text Available Dynamical behavior of a class of Cohen-Grossberg models with multiple time-varying delays is studied in detail. Sufficient delay-dependent criteria to ensure local and global asymptotic stabilities of the equilibrium of this network are derived by constructing suitable Lyapunov functionals. The obtained conditions are shown to be less conservative and restrictive than those reported in the known literature. Some numerical examples are included to demonstrate our results.

  4. A novel delay-dependent criterion for delayed neural networks of neutral type

    International Nuclear Information System (INIS)

    Lee, S.M.; Kwon, O.M.; Park, Ju H.

    2010-01-01

    This Letter considers a robust stability analysis method for delayed neural networks of neutral type. By constructing a new Lyapunov functional, a novel delay-dependent criterion for the stability is derived in terms of LMIs (linear matrix inequalities). A less conservative stability criterion is derived by using nonlinear properties of the activation function of the neural networks. Two numerical examples are illustrated to show the effectiveness of the proposed method.

  5. Maternal Obesity: Risks for Developmental Delays in Early Childhood.

    Science.gov (United States)

    Duffany, Kathleen O'Connor; McVeigh, Katharine H; Kershaw, Trace S; Lipkind, Heather S; Ickovics, Jeannette R

    2016-02-01

    To assess the risk for neurodevelopmental delays for children of mothers who were obese (≥200 pounds) prior to pregnancy, and to characterize delays associated with maternal obesity among children referred to and found eligible to receive Early Intervention Program services. We conducted a retrospective cohort study (N = 541,816) using a population-based New York City data warehouse with linked birth and Early Intervention data. Risks for children suspected of a delay and 'significantly delayed', with two moderate or one severe delay, were calculated. Among the group of children eligible by delay for Early Intervention, analyses assessed risk for being identified with a moderate-to-severe delay across each of five functional domains as well as risks for multiple delays. Children of mothers who were obese were more likely to be suspected of a delay (adjusted RR 1.19 [CI 1.15-1.22]) and borderline association for 'significantly delayed' (adjusted RR 1.01 [CI 1.00-1.02). Among children eligible by delay, children of mothers who were obese evidenced an increased risk for moderate-to-severe cognitive (adjusted RR 1.04 [CI 1.02-1.07]) and physical (adjusted RR 1.04 [CI 1.01-1.08]) delays and for global developmental delay (adjusted RR 1.05 [CI 1.01-1.08]). Maternal obesity is associated with increased risk of developmental delay in offspring. Among children with moderate or severe delays, maternal obesity is associated with increased risk of cognitive and physical delays as well as with increased risk for global developmental delay. While causation remains uncertain, this adds to the growing body of research reporting an association between maternal obesity and neurodevelopmental delays in offspring.

  6. Delay-Dependent Guaranteed Cost Control of an Interval System with Interval Time-Varying Delay

    Directory of Open Access Journals (Sweden)

    Xiao Min

    2009-01-01

    Full Text Available This paper concerns the problem of the delay-dependent robust stability and guaranteed cost control for an interval system with time-varying delay. The interval system with matrix factorization is provided and leads to less conservative conclusions than solving a square root. The time-varying delay is assumed to belong to an interval and the derivative of the interval time-varying delay is not a restriction, which allows a fast time-varying delay; also its applicability is broad. Based on the Lyapunov-Ktasovskii approach, a delay-dependent criterion for the existence of a state feedback controller, which guarantees the closed-loop system stability, the upper bound of cost function, and disturbance attenuation lever for all admissible uncertainties as well as out perturbation, is proposed in terms of linear matrix inequalities (LMIs. The criterion is derived by free weighting matrices that can reduce the conservatism. The effectiveness has been verified in a number example and the compute results are presented to validate the proposed design method.

  7. REASONS FOR PATIENT DELAYS & HEALTH SYSTEM DELAYS FOR TUBERCULOSIS IN SOUTH INDIA

    Directory of Open Access Journals (Sweden)

    Kapil Goel

    2011-12-01

    Full Text Available Background: Globally, the burden of Tuberculosis is escalating. Early diagnosis and prompt initiation of tuberculosis treatment is essential for an effective tuberculosis control programme. Objectives: To study the self reported reasons for patient and health system (diagnosis & treatment delays in Tuberculosis patients. Methods: A community based cross sectional study was conducted among 98 new sputum positive TB cases aged > 15 years registered under RNTCP from Oct 2006 to June 2007 & receiving treatment under DOTS in Udupi taluk by interviewing them. Results: Total 98 patients were recruited and 68% were males. Out of 17 patients with patient delays, 82% felt that their symptoms were not severe, 71% felt that patient delay was due to lack of awareness and 71% did not take it seriously. Out of 86 patients with health system delays, 82.6% of patients mentioned that doctor has not advised for sputum examination, 76.7% of patients told that they first consulted a private doctor, 21% of them mentioned that doctor was unaware to diagnose TB. Conclusion: Symptoms not severe is the main reason for the patient delay and doctor didn’t advise for sputum examination is the main reason for health system delays.

  8. Time-delayed feedback control of diffusion in random walkers

    Science.gov (United States)

    Ando, Hiroyasu; Takehara, Kohta; Kobayashi, Miki U.

    2017-07-01

    Time delay in general leads to instability in some systems, while specific feedback with delay can control fluctuated motion in nonlinear deterministic systems to a stable state. In this paper, we consider a stochastic process, i.e., a random walk, and observe its diffusion phenomenon with time-delayed feedback. As a result, the diffusion coefficient decreases with increasing delay time. We analytically illustrate this suppression of diffusion by using stochastic delay differential equations and justify the feasibility of this suppression by applying time-delayed feedback to a molecular dynamics model.

  9. Glue-paste linings

    DEFF Research Database (Denmark)

    Fuster-López, Laura; Andersen, Cecil Krarup; Bouillon, Nicolas

    2017-01-01

    Glue-paste linings of (Western) canvas paintings have been performed with a variety of materials throughout history and are present in a very significant amount of artworks in collections in Europe and elsewhere. Cereal flours and animal glues were usually the main ingredients because they were r...

  10. Product line design

    Czech Academy of Sciences Publication Activity Database

    Anderson, S. P.; Celik, Levent

    2015-01-01

    Roč. 157, May (2015), s. 517-526 ISSN 0022-0531 R&D Projects: GA ČR(CZ) GA15-22540S Institutional support: PRVOUK-P23 Keywords : product line design * product differentiation * second-degree price discrimination Subject RIV: AH - Economics Impact factor: 1.097, year: 2015

  11. K-line photometry

    International Nuclear Information System (INIS)

    Henry, R.C.

    1979-01-01

    A brief review is given of more than a decade of work involving measurement of the strength of the K line of calcium in A-type stars. The effects of interstellar reddening are reexamined, and an improved estimate for the range in calcium abundance among field stars is obtained. (Auth.)

  12. SAF line pellet gaging

    International Nuclear Information System (INIS)

    Jedlovec, D.R.; Bowen, W.W.; Brown, R.L.

    1983-10-01

    Automated and remotely controlled pellet inspection operations will be utilized in the Secure Automated Fabrication (SAF) line. A prototypic pellet gage was designed and tested to verify conformance to the functions and requirements for measurement of diameter, surface flaws and weight-per-unit length

  13. Bike Map Lines

    Data.gov (United States)

    Town of Chapel Hill, North Carolina — Chapel Hill Bike Map Lines from KMZ file.This data came from the wiki comment board for the public, not an “official map” showing the Town of Chapel Hill's plans or...

  14. Drawing the Line

    DEFF Research Database (Denmark)

    Holm, Isak Winkel

    2016-01-01

    of judgement that distinguishes between the inside and outside of a political community, between citizens and zombies. Second, the chapter focuses on the rhetorics applied to draw the line between rights-bearers and the rightless. ‘Prophetic’ speech, echoing the language of the Old Testament prophets, is vital...

  15. Developing Green Line Products

    DEFF Research Database (Denmark)

    Muñoz-Marin, Ana Maria; Lassen, Astrid Heidemann; Poulsen, Søren Bolvig

    2011-01-01

    This publication is based on the Master thesis “User-driven ecoinnovation process: Towards the implementation of the Green product line at JELD-WEN” written by Ana Maria Muñoz-Marin as her Graduation Project for the MSc. Global Innovation Management degree. The company-based experiment was carried...

  16. Magnetic field line Hamiltonian

    International Nuclear Information System (INIS)

    Boozer, A.H.

    1984-03-01

    The magnetic field line Hamiltonian and the associated canonical form for the magnetic field are important concepts both for understanding toroidal plasma physics and for practical calculations. A number of important properties of the canonical or Hamiltonian representation are derived and their importance is explained

  17. Mixed Lubricated Line Contacts

    NARCIS (Netherlands)

    Faraon, I.C.

    2005-01-01

    The present work deals with friction in mixed lubricated line contacts. Components in systems are becoming smaller and due to, for instance power transmitted, partial contact may occur. In industrial applications, friction between the moving contacting surfaces cannot be avoided, therefore it is

  18. Lined canvas paintings

    DEFF Research Database (Denmark)

    Krarup Andersen, Cecil

    2013-01-01

    at 50% RH but increased the stress level severely in dry conditions and offered no support to the painting at 70-80 % RH. This means that the traditional glue-paste lining techniques and the wax-resin technique in high RH seem to limit the advisable RH fluctuation in a cultural institution. Conversely...

  19. LEAR: antiproton extraction lines

    CERN Multimedia

    Photographic Service

    1992-01-01

    Antiprotons, decelerated in LEAR to a momentum of 100 MeV/c (kinetic energy of 5.3 MeV), were delivered to the experiments in an "Ultra-Slow Extraction", dispensing some 1E9 antiprotons over times counted in hours. Beam-splitters and a multitude of beam-lines allowed several users to be supplied simultaneously.

  20. Labelling subway lines

    NARCIS (Netherlands)

    Garrido, M.A.; Iturriaga, C.; Márquez, A.; Portillo, J.R.; Reyes, P.; Wolff, A.; Eades, P.; Takaoka, T.

    2001-01-01

    Graphical features on map, charts, diagrams and graph drawings usually must be annotated with text labels in order to convey their meaning. In this paper we focus on a problem that arises when labeling schematized maps, e.g. for subway networks. We present algorithms for labeling points on a line

  1. Subjective poverty line definitions

    NARCIS (Netherlands)

    J. Flik; B.M.S. van Praag (Bernard)

    1991-01-01

    textabstractIn this paper we will deal with definitions of subjective poverty lines. To measure a poverty threshold value in terms of household income, which separates the poor from the non-poor, we take into account the opinions of all people in society. Three subjective methods will be discussed

  2. Building with a Line

    Science.gov (United States)

    Hubbert, Beth

    2011-01-01

    Architecture is a versatile, multifaceted area to study in the artroom with multiple age levels. It can easily stimulate a study of basic line, shape, and various other art elements and principles. It can then be extended into a more extensive study of architectural elements, styles, specific architects, architecture of different cultures, and…

  3. Biosynthesis: Reprogramming assembly lines

    Science.gov (United States)

    Menon, Binuraj R. K.; Jenner, Matthew

    2018-03-01

    Rational engineering of biosynthetic assembly lines for production of new compounds is an attractive prospect, yet it presents many challenges. Learning from biology, some of the rules for expanding the chemical diversity of non-ribosomal peptides have been uncovered in two recent studies.

  4. Magnetic field line Hamiltonian

    International Nuclear Information System (INIS)

    Boozer, A.H.

    1985-02-01

    The basic properties of the Hamiltonian representation of magnetic fields in canonical form are reviewed. The theory of canonical magnetic perturbation theory is then developed and applied to the time evolution of a magnetic field embedded in a toroidal plasma. Finally, the extension of the energy principle to tearing modes, utilizing the magnetic field line Hamiltonian, is outlined

  5. Defining line replaceable units

    NARCIS (Netherlands)

    Parada Puig, J. E.; Basten, R. J I

    2015-01-01

    Defective capital assets may be quickly restored to their operational condition by replacing the item that has failed. The item that is replaced is called the Line Replaceable Unit (LRU), and the so-called LRU definition problem is the problem of deciding on which item to replace upon each type of

  6. Fundamentals of Delayed Coking Joint Industry Project

    Energy Technology Data Exchange (ETDEWEB)

    Michael Volk; Keith Wisecarver

    2003-09-26

    Delayed coking evolved steadily over the early to mid 1900s to enable refiners to convert high boiling, residual petroleum fractions to light products such as gasoline. Pound for pound, coking is the most energy intensive of any operation in a modern refinery. Large amounts of energy are required to heat the thick, poor-quality petroleum residuum to the 900 to 950 degrees F required to crack the heavy hydrocarbon molecules into lighter, more valuable products. One common misconception of delayed coking is that the product coke is a disadvantage. Although coke is a low valued (near zero economic value) byproduct, compared to transportation fuels, there is a significant worldwide trade and demand for coke as it is an economical fuel. Coke production has increased steadily over the last ten years, with further increases forecast for the foreseeable future. Current domestic production is near 111,000 tons per day. A major driving force behind this increase is the steady decline in crude quality available to refiners. Crude slates are expected to grow heavier with higher sulfur contents while environmental restrictions are expected to significantly reduce the demand for high-sulfur residual fuel oil. Light sweet crudes will continue to be available and in even greater demand than they are today. Refiners will be faced with the choice of purchasing light sweet crudes at a premium price, or adding bottom of the barrel upgrading capability, through additional new investments, to reduce the production of high-sulfur residual fuel oil and increase the production of low-sulfur distillate fuels. A second disadvantage is that liquid products from cokers frequently are unstable, i.e., they rapidly form gum and sediments. Because of intermediate investment and operating costs, delayed coking has increased in popularity among refiners worldwide. Based on the 2000 Worldwide Refining Survey published in the Oil and Gas, the delayed coking capacity for 101 refineries around the world

  7. Delayed Luminescence and Biophotons from Biological Materials

    Science.gov (United States)

    Knoesel, Ernst; Hann, Patrick; Garzon, Maria; Pfeiffer, Erik; Lofland, Samuel

    2008-03-01

    There has recently been increased interest in the field of biophotonics, since it is a non-invasive technique. Many biological systems, such as yeast, bacteria, leaves, seeds, and algae display the unusual phenomenon of a weak, delayed luminescence on the timescale of seconds to minutes after transient illumination. It is also observed that the time decay of the biophotonic emission is not exponential, even after the delay, and that there can be oscillations in intensity with time, which depend on the duration of the illumination. Results from two types of yeast, i.e. bread yeast, and saccharomyces, as well as those from several types of algae are presented. Possible mechanisms for the source of the ultraweak photon emission are discussed.

  8. Convergent dynamics for multistable delayed neural networks

    International Nuclear Information System (INIS)

    Shih, Chih-Wen; Tseng, Jui-Pin

    2008-01-01

    This investigation aims at developing a methodology to establish convergence of dynamics for delayed neural network systems with multiple stable equilibria. The present approach is general and can be applied to several network models. We take the Hopfield-type neural networks with both instantaneous and delayed feedbacks to illustrate the idea. We shall construct the complete dynamical scenario which comprises exactly 2 n stable equilibria and exactly (3 n − 2 n ) unstable equilibria for the n-neuron network. In addition, it is shown that every solution of the system converges to one of the equilibria as time tends to infinity. The approach is based on employing the geometrical structure of the network system. Positively invariant sets and componentwise dynamical properties are derived under the geometrical configuration. An iteration scheme is subsequently designed to confirm the convergence of dynamics for the system. Two examples with numerical simulations are arranged to illustrate the present theory

  9. Estimation of network path segment delays

    Science.gov (United States)

    Nichols, Kathleen Marie

    2018-05-01

    A method for estimation of a network path segment delay includes determining a scaled time stamp for each packet of a plurality of packets by scaling a time stamp for each respective packet to minimize a difference of at least one of a frequency and a frequency drift between a transport protocol clock of a host and a monitoring point. The time stamp for each packet is provided by the transport protocol clock of the host. A corrected time stamp for each packet is determined by removing from the scaled time stamp for each respective packet, a temporal offset between the transport protocol clock and the monitoring clock by minimizing a temporal delay variation of the plurality of packets traversing a segment between the host and the monitoring point.

  10. Approximating chaotic saddles for delay differential equations.

    Science.gov (United States)

    Taylor, S Richard; Campbell, Sue Ann

    2007-04-01

    Chaotic saddles are unstable invariant sets in the phase space of dynamical systems that exhibit transient chaos. They play a key role in mediating transport processes involving scattering and chaotic transients. Here we present evidence (long chaotic transients and fractal basins of attraction) of transient chaos in a "logistic" delay differential equation. We adapt an existing method (stagger-and-step) to numerically construct the chaotic saddle for this system. This is the first such analysis of transient chaos in an infinite-dimensional dynamical system, and in delay differential equations in particular. Using Poincaré section techniques we illustrate approaches to visualizing the saddle set, and confirm that the saddle has the Cantor-like fractal structure consistent with a chaotic saddle generated by horseshoe-type dynamics.

  11. Differential games in economic systems with delays

    Science.gov (United States)

    Kim, A. V.; Kormyshev, V. M.; Novikov, M. Yu.; Nikonov, M. A.

    2017-11-01

    In the paper, we consider application of i-smooth analysis (A.V. Kim, 2015) to differential games with delays in economics (Dockner E.J., et all, 2000; R. Isaacs, 1999). The approach is developed in the framework of the theory of positional differential games (N.N. Krasovskii, A.I. Subbotin, 1988; A.V. Kryazhimskii, Yu.S. Osipov, 1973; Yu.S. Osipov, J. Appl. Math. Mech. Vol. 35, № 1, № 6, 1971) and is based on application of the extremal shift strategy. We consider basic notions and constructions of the approach-evasion problem for linear systems with delays. The necessary and sufficient conditions of solvability the approach-evasion problem in terms of special u-stable sets are presented in another paper.

  12. Delayed reactions to reusable protective gloves.

    Science.gov (United States)

    Pontén, Ann; Dubnika, Inese

    2009-04-01

    The materials in plastic protective gloves are thought to cause less contact allergy than rubber gloves. Our aim was to estimate the frequency of delayed reactions to different types of reusable protective gloves among dermatitis patients. 2 x 2 cm pieces of polyvinyl chloride (PVC) gloves, nitrile gloves, and natural rubber latex (NRL) gloves were tested as is in consecutive dermatitis patients tested with the baseline series. Among 658 patients, 6 patients reacted to PVC gloves and 6 patients to the NRL gloves. None reacted to both these types of gloves. Five of six patients with reactions to rubber gloves reacted to thiuram mix in the baseline series. Delayed reactions to reusable PVC gloves may be as common as to reusable NRL gloves. In contrast to most reactions to the NRL glove, the reactions to the PVC glove had no obvious association with reactions to any allergen(s) in the baseline series.

  13. Approximating chaotic saddles for delay differential equations

    Science.gov (United States)

    Taylor, S. Richard; Campbell, Sue Ann

    2007-04-01

    Chaotic saddles are unstable invariant sets in the phase space of dynamical systems that exhibit transient chaos. They play a key role in mediating transport processes involving scattering and chaotic transients. Here we present evidence (long chaotic transients and fractal basins of attraction) of transient chaos in a “logistic” delay differential equation. We adapt an existing method (stagger-and-step) to numerically construct the chaotic saddle for this system. This is the first such analysis of transient chaos in an infinite-dimensional dynamical system, and in delay differential equations in particular. Using Poincaré section techniques we illustrate approaches to visualizing the saddle set, and confirm that the saddle has the Cantor-like fractal structure consistent with a chaotic saddle generated by horseshoe-type dynamics.

  14. Energy management - The delayed flap approach

    Science.gov (United States)

    Bull, J. S.

    1976-01-01

    Flight test evaluation of a Delayed Flap approach procedure intended to provide reductions in noise and fuel consumption is underway using the NASA CV-990 test aircraft. Approach is initiated at a high airspeed (240 kt) and in a drag configuration that allows for low thrust. The aircraft is flown along the conventional ILS glide slope. A Fast/Slow message display signals the pilot when to extend approach flaps, landing gear, and land flaps. Implementation of the procedure in commercial service may require the addition of a DME navigation aid co-located with the ILS glide slope transmitter. The Delayed Flap approach saves 250 lb of fuel over the Reduced Flap approach, with a 95 EPNdB noise contour only 43% as large.

  15. Tropospheric Delay from VLBI and GNSS Measurements

    Science.gov (United States)

    Gubanov, V. S.

    2018-02-01

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

  16. Climate models with delay differential equations

    Science.gov (United States)

    Keane, Andrew; Krauskopf, Bernd; Postlethwaite, Claire M.

    2017-11-01

    A fundamental challenge in mathematical modelling is to find a model that embodies the essential underlying physics of a system, while at the same time being simple enough to allow for mathematical analysis. Delay differential equations (DDEs) can often assist in this goal because, in some cases, only the delayed effects of complex processes need to be described and not the processes themselves. This is true for some climate systems, whose dynamics are driven in part by delayed feedback loops associated with transport times of mass or energy from one location of the globe to another. The infinite-dimensional nature of DDEs allows them to be sufficiently complex to reproduce realistic dynamics accurately with a small number of variables and parameters. In this paper, we review how DDEs have been used to model climate systems at a conceptual level. Most studies of DDE climate models have focused on gaining insights into either the global energy balance or the fundamental workings of the El Niño Southern Oscillation (ENSO) system. For example, studies of DDEs have led to proposed mechanisms for the interannual oscillations in sea-surface temperature that is characteristic of ENSO, the irregular behaviour that makes ENSO difficult to forecast and the tendency of El Niño events to occur near Christmas. We also discuss the tools used to analyse such DDE models. In particular, the recent development of continuation software for DDEs makes it possible to explore large regions of parameter space in an efficient manner in order to provide a "global picture" of the possible dynamics. We also point out some directions for future research, including the incorporation of non-constant delays, which we believe could improve the descriptive power of DDE climate models.

  17. Climate models with delay differential equations.

    Science.gov (United States)

    Keane, Andrew; Krauskopf, Bernd; Postlethwaite, Claire M

    2017-11-01

    A fundamental challenge in mathematical modelling is to find a model that embodies the essential underlying physics of a system, while at the same time being simple enough to allow for mathematical analysis. Delay differential equations (DDEs) can often assist in this goal because, in some cases, only the delayed effects of complex processes need to be described and not the processes themselves. This is true for some climate systems, whose dynamics are driven in part by delayed feedback loops associated with transport times of mass or energy from one location of the globe to another. The infinite-dimensional nature of DDEs allows them to be sufficiently complex to reproduce realistic dynamics accurately with a small number of variables and parameters. In this paper, we review how DDEs have been used to model climate systems at a conceptual level. Most studies of DDE climate models have focused on gaining insights into either the global energy balance or the fundamental workings of the El Niño Southern Oscillation (ENSO) system. For example, studies of DDEs have led to proposed mechanisms for the interannual oscillations in sea-surface temperature that is characteristic of ENSO, the irregular behaviour that makes ENSO difficult to forecast and the tendency of El Niño events to occur near Christmas. We also discuss the tools used to analyse such DDE models. In particular, the recent development of continuation software for DDEs makes it possible to explore large regions of parameter space in an efficient manner in order to provide a "global picture" of the possible dynamics. We also point out some directions for future research, including the incorporation of non-constant delays, which we believe could improve the descriptive power of DDE climate models.

  18. Dynamics in a delayed-neural network

    International Nuclear Information System (INIS)

    Yuan Yuan

    2007-01-01

    In this paper, we consider a neural network of four identical neurons with time-delayed connections. Some parameter regions are given for global, local stability and synchronization using the theory of functional differential equations. The root distributions in the corresponding characteristic transcendental equation are analyzed, Pitchfork bifurcation, Hopf and equivariant Hopf bifurcations are investigated by revealing the center manifolds and normal forms. Numerical simulations are shown the agreements with the theoretical results

  19. Direct 'delay' reductions of the Toda equation

    International Nuclear Information System (INIS)

    Joshi, Nalini

    2009-01-01

    A new direct method of obtaining reductions of the Toda equation is described. We find a canonical and complete class of all possible reductions under certain assumptions. The resulting equations are ordinary differential-difference equations, sometimes referred to as delay-differential equations. The representative equation of this class is hypothesized to be a new version of one of the classical Painleve equations. The Lax pair associated with this equation is obtained, also by reduction. (fast track communication)

  20. CERN boss quashes LHC delay rumours

    CERN Multimedia

    2007-01-01

    "Robert Aymar, the director general of CERN, has dispelled rumours that a series of buckled electrical connectors at the Large Hadron Collider will delay the accelerator's official start-up date of May 2008. Writing in this week's CERN Bulletin, Aymar says that the problem concerns only a small percentage of the connectors and that it is "business as usual" for bringing the new accelerator online." (1,5 page)

  1. Bilingualism delays clinical manifestation of Alzheimer's disease

    OpenAIRE

    Woumans, Evy; Santens, Patrick; Sieben, Anne; Versijpt, Jan; Stevens, Michaël; Duyck, Wouter

    2015-01-01

    The current study investigated the effects of bilingualism on the clinical manifestation of Alzheimer's disease (AD) in a European sample of patients. We assessed all incoming AD patients in two university hospitals within a specified timeframe. Sixty-nine monolinguals and 65 bilinguals diagnosed with probable AD were compared for time of clinical AD manifestation and diagnosis. The influence of other potentially interacting variables was also examined. Results indicated a significant delay f...

  2. Accelerating Smaller Cutbacks to Delay Larger Ones?

    DEFF Research Database (Denmark)

    Tepe, Markus; Vanhuysse, Pieter

    2012-01-01

    . Investigating both medium and large cutbacks in ageing welfare states, we test whether, in addition to conventional demographic and economic variables, political-institutional variables capturing partisanship (political ideology), electioneering (political cycle), and institutional constraints (political...... effects of unemployment and population aging: these socio-demographic variables tend to delay large-size cutbacks, but to accelerate medium-size cutbacks in pension generosity, possibly because they function as alarm bell signals urging policymakers to take still feasible incremental action through...

  3. Delayed Antiwindup Control Using a Decoupling Structure

    Directory of Open Access Journals (Sweden)

    Huawei Zhu

    2013-01-01

    Full Text Available This paper investigates the antiwindup (AW control problem for plants with input saturation. The AW compensator is not activated as soon as input saturation occurs as usual. A delayed decoupling structure is first proposed. Then, appropriate linear matrix inequalities (LMIs are developed to determine a plant-order AW compensator. Effectiveness of the presented AW technique is illustrated by a fighter aircraft model.

  4. Torness delay is storing up trouble

    International Nuclear Information System (INIS)

    Cavenagh, Andrew.

    1994-01-01

    A recent decision by the Scottish Office to delay planning permission for the construction of a 50 million dry store for spent nuclear fuel at Torness Power Station is proving frustrating and inexplicable to many in the nuclear industry. The possible reasons for this apparent about face in government policy on spent fuel management are debated and the economic ramifications of the decision for British Nuclear Fuels Limited (BNFL), if the store were to go ahead, are outlined. (UK)

  5. Earth system commitments due to delayed mitigation

    International Nuclear Information System (INIS)

    Pfister, Patrik L; Stocker, Thomas F

    2016-01-01

    As long as global CO 2 emissions continue to increase annually, long-term committed Earth system changes grow much faster than current observations. A novel metric linking this future growth to policy decisions today is the mitigation delay sensitivity (MDS), but MDS estimates for Earth system variables other than peak temperature (ΔT max ) are missing. Using an Earth System Model of Intermediate Complexity, we show that the current emission increase rate causes a ΔT max increase roughly 3–7.5 times as fast as observed warming, and a millenial steric sea level rise (SSLR) 7–25 times as fast as observed SSLR, depending on the achievable rate of emission reductions after the peak of emissions. These ranges are only slightly affected by the uncertainty range in equilibrium climate sensitivity, which is included in the above values. The extent of ocean acidification at the end of the century is also strongly dependent on the starting time and rate of emission reductions. The preservable surface ocean area with sufficient aragonite supersaturation for coral reef growth is diminished globally at an MDS of roughly 25%–80% per decade. A near-complete loss of this area becomes unavoidable if mitigation is delayed for a few years to decades. Also with respect to aragonite, 12%–18% of the Southern Ocean surface become undersaturated per decade, if emission reductions are delayed beyond 2015–2040. We conclude that the consequences of delaying global emission reductions are much better captured if the MDS of relevant Earth system variables is communicated in addition to current trends and total projected future changes. (letter)

  6. Imprints of the quasar structure in time-delay light curves: Microlensing-aided reverberation mapping

    Science.gov (United States)

    Sluse, D.; Tewes, M.

    2014-11-01

    The advent of large area photometric surveys has raised a great deal of interest in the possibility of using broadband photometric data, instead of spectra, to measure the size of the broad line region of active galactic nuclei. We describe here a new method that uses time-delay lensed quasars where one or several images are affected by microlensing due to stars in the lensing galaxy. Because microlensing decreases (or increases) the flux of the continuum compared to the broad line region, it changes the contrast between these two emission components. We show that this effect can be used to effectively disentangle the intrinsic variability of those two regions, offering the opportunity to perform reverberation mapping based on single-band photometric data. Based on simulated light curves generated using a damped random walk model of quasar variability, we show that measurement of the size of the broad line region can be achieved using this method, provided one spectrum has been obtained independently during the monitoring. This method is complementary to photometric reverberation mapping and could also be extended to multi-band data. Because the effect described above produces a variability pattern in difference light curves between pairs of lensed images that is correlated with the time-lagged continuum variability, it can potentially produce systematic errors in measurement of time delays between pairs of lensed images. Simple simulations indicate that time-delay measurement techniques that use a sufficiently flexible model for the extrinsic variability are not affected by this effect and produce accurate time delays.

  7. Delayed somatic effects following extended radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Slanina, J

    1977-10-27

    A group of 135 patients was investigated, who suffered from Hodgkin's disease with long-term remission following radiotherapy. By restricting the investigations to the patient group with long-term remission and correlative examinations, differentiation was made between exclusive or principal delayed radiation effects and delayed effects due to other factors. The study reports the most significant results obtained in the fields of catamnesis, laboratory diagnostics, hematology, pulmology, cardiology, thyroid function tests, neurology, andrology and dermatology. Due to the numerous detectable delayed effects the group of patients with long-term remission receives a special status. Although those effects are in no proportion to the deletary risks of an untreated Hodgkin's disease and though they are consequently tolerable in the present state of the therapeutic development, they must initiate the completion of the therapeutic concept including performance of radiotherapy and aftercare, because only then the risk for the patient provoked by these effects, which ranges beyond the malignity of this disease can be reduced or prevented.

  8. PROMPT Ia SUPERNOVAE ARE SIGNIFICANTLY DELAYED

    International Nuclear Information System (INIS)

    Raskin, Cody; Scannapieco, Evan; Rhoads, James; Della Valle, Massimo

    2009-01-01

    The time delay between the formation of a population of stars and the onset of type Ia supernovae (SNe Ia) sets important limits on the masses and nature of SN Ia progenitors. Here, we use a new observational technique to measure this time delay by comparing the spatial distributions of SNe Ia to their local environments. Previous work attempted such analyses encompassing the entire host of each SN Ia, yielding inconclusive results. Our approach confines the analysis only to the relevant portions of the hosts, allowing us to show that even so-called prompt SNe Ia that trace star formation on cosmic timescales exhibit a significant delay time of 200-500 million years. This implies that either the majority of Ia companion stars have main-sequence masses less than 3 M sun , or that most SNe Ia arise from double white dwarf binaries. Our results are also consistent with a SNe Ia rate that traces the white dwarf formation rate, scaled by a fixed efficiency factor.

  9. Best matching Barenblatt profiles are delayed

    International Nuclear Information System (INIS)

    Dolbeault, Jean; Toscani, Giuseppe

    2015-01-01

    The growth of the second moments of the solutions of fast diffusion equations is asymptotically governed by the behavior of self-similar solutions. However, at next order, there is a correction term which amounts to a delay depending on the nonlinearity and on a distance of the initial data to the set of self-similar Barenblatt solutions. This distance can be measured in terms of a relative entropy to the best matching Barenblatt profile. This best matching Barenblatt function determines a scale. In new variables based on this scale, which are given by a self-similar change of variables if and only if the initial datum is one of the Barenblatt profiles, the typical scale is monotone and has a limit. Coming back to original variables, the best matching Barenblatt profile is delayed compared to the self-similar solution with same initial second moment as the initial datum. Such a delay is a new phenomenon, which has to be taken into account for instance when fitting experimental data. (paper)

  10. Atrial fibrillation and delayed gastric emptying.

    Directory of Open Access Journals (Sweden)

    Isadora C Botwinick

    Full Text Available BACKGROUND: Atrial fibrillation and delayed gastric emptying (DGE are common after pancreaticoduodenectomy. Our aim was to investigate a potential relationship between atrial fibrillation and DGE, which we defined as failure to tolerate a regular diet by the 7(th postoperative day. METHODS: We performed a retrospective chart review of 249 patients who underwent pancreaticoduodenectomy at our institution between 2000 and 2009. Data was analyzed with Fisher exact test for categorical variables and Mann-Whitney U or unpaired T-test for continuous variables. RESULTS: Approximately 5% of the 249 patients included in the analysis experienced at least one episode of postoperative atrial fibrillation. Median age of patients with atrial fibrillation was 74 years, compared with 66 years in patients without atrial fibrillation (p = 0.0005. Patients with atrial fibrillation were more likely to have a history of atrial fibrillation (p = 0.03. 92% of the patients with atrial fibrillation suffered from DGE, compared to 46% of patients without atrial fibrillation (p = 0.0007. This association held true when controlling for age. CONCLUSION: Patients with postoperative atrial fibrillation are more likely to experience delayed gastric emptying. Interventions to manage delayed gastric function might be prudent in patients at high risk for postoperative atrial fibrillation.

  11. Delayed shear enhancement in mesoscale atmospheric dispersion

    Energy Technology Data Exchange (ETDEWEB)

    Moran, M.D. [Atmospheric Environment Service, Ontario (Canada); Pielke, R.A. [Colorado State Univ., Fort Collins, CO (United States)

    1994-12-31

    Mesoscale atmospheric dispersion (MAD) is more complicated than smaller-scale dispersion because the mean wind field can no longer be considered steady or horizontally homogeneous over mesoscale time and space scales. Wind shear also plays a much more important role on the mesoscale: horizontal dispersion can be enhanced and often dominated by vertical wind shear on these scales through the interaction of horizontal differential advection and vertical mixing. Just over 30 years ago, Pasquill suggested that this interaction need not be simultaneous and that the combination of differential horizontal advection with delayed or subsequent vertical mixing could maintain effective horizontal diffusion in spite of temporal or spatial reductions in boundary-layer turbulence intensity. This two-step mechanism has not received much attention since then, but a recent analysis of observations from and numerical simulations of two mesoscale tracer experiments suggests that delayed shear enhancement can play an important role in MAD. This paper presents an overview of this analysis, with particular emphasis on the influence of resolvable vertical shear on MAD in these two case studies and the contributions made by delayed shear enhancement.

  12. Development of delayed radiation necrosis. Case report

    Energy Technology Data Exchange (ETDEWEB)

    Ohara, ShigFeki; Takagi, Terumasa [Meitetsu Hospital, Nagoya (Japan); Shibata, Taichiro; Nagai, Hajime

    1983-04-01

    The authors discussed the developing process of delayed radiation necrosis of the brain from the case of a 42-year-old female who developed intracranial hypertension and left hemiparesis 5 and a half years after radiotherapy for pituitary adenoma. The initial sign of radiation necrosis was from a CT scan taken 3 and a half years after radiotherapy showing an irregular low density lesion in the right temporal lobe. CT scan 2 years later demonstrated displacement of the midline structures to the left and a larger low density lesion with partially high density in the right MCA territory that was enhanced with intravenous contrast medium. Recovery after a right temporal lobectomy and administration of steroid hormone were uneventful. Eight months later there were no signs of raised intracranial pressure nor of neurological deficits. Tissues obtained from the right temporal lobe at lobectomy revealed the characteristic changes of delayed radiation necrosis; a mixture of fresh, recent, and old vascular lesions in the same specimen. From these findings, it was speculated that delayed radiation necrosis might initially occur within several years after radiotherapy and might gradually take a progressive and extended course, even in cases whose clinical symptoms develop much later.

  13. Delays in the operating room: signs of an imperfect system.

    Science.gov (United States)

    Wong, Janice; Khu, Kathleen Joy; Kaderali, Zul; Bernstein, Mark

    2010-06-01

    Delays in the operating room have a negative effect on its efficiency and the working environment. In this prospective study, we analyzed data on perioperative system delays. One neurosurgeon prospectively recorded all errors, including perioperative delays, for consecutive patients undergoing elective procedures from May 2000 to February 2009. We analyzed the prevalence, causes and impact of perioperative system delays that occurred in one neurosurgeon's practice. A total of 1531 elective surgical cases were performed during the study period. Delays were the most common type of error (33.6%), and more than half (51.4%) of all cases had at least 1 delay. The most common cause of delay was equipment failure. The first cases of the day and cranial cases had more delays than subsequent cases and spinal cases, respectively. A delay in starting the first case was associated with subsequent delays. Delays frequently occur in the operating room and have a major effect on patient flow and resource utilization. Thorough documentation of perioperative delays provides a basis for the development of solutions for improving operating room efficiency and illustrates the principles underlying the causes of operating room delays across surgical disciplines.

  14. CONCEPTS OF IMPROVING CURRENT PROTECTION OF POWER-GRID LINES

    Directory of Open Access Journals (Sweden)

    F. A. Romaniuk

    2015-01-01

    Full Text Available The  6–35  kV  power-grid  current  protection  serves  to  protect  the  transmission  lines against phase-to-phase short-circuits. The major disadvantage of it lies in the relatively large time delays of the last stages especially in the main sections of the grid owing to the stepped relay characteristics as well as a large number of the steps. A full-fledged protection of the 6–35 kV lines against inter-phase short circuits can be provided by the two-stage current protection: the first stage being the current cutoff without any time delay and the second stage – the maximum current protection where the time delay is linear contingent on the distance between the protection placement and the fault-point location. The article introduces the rating formulae for the time delays of the second-stage and their exemplary graphic presentation. The authors offer a variant for solving the problem with computation of the second-stage time delays in those instances where several feeders diverge from the bus bars of the substation located in the end of the protected line.Improving current protections for the 6–35 kV transmission lines with one-end power supply against interphase short-circuits can be based on the collective application of the following principles: accounting for the type and location of the short-circuit which provides for the high-performance cutoff zone instantaneous expansion and its independence on the mode of failure and the grid operation mode. It also allows increase of the last stage sensitiveness towards asymmetrical short-circuits; detection of the short-circuit location only on the results of fault currents measurement which simplifies the protection implementation; realization of the last (second protection stage with linear-dependent time delay which ensures potentiality of its operation speed increase.

  15. OCULAR DISORDERS IN CHILDREN WITH DEVELOPMENTAL DELAY

    Directory of Open Access Journals (Sweden)

    Meera Suresh Joshi

    2017-08-01

    Full Text Available BACKGROUND In India, an estimated 1.5-2.5% children below 2 years of age are developmentally delayed. A higher incidence of ocular disability is seen in these children, refractive errors and strabismus being most common. These can add to the overall burden of health as most of them have developmental comorbidities. The aim of the study is to study the ocular disorders in children with developmental delay. MATERIALS AND METHODS We studied 112 children between the 2-12 years of age diagnosed to have developmental delay. All the subjects underwent a detailed ophthalmic evaluation including visual acuity testing using Snellen’s charts (3m and 6m and Log MAR charts (recorded as per Snellen’s vision testing to maintain uniformity, cycloplegic refraction, torchlight and slit-lamp evaluation and dilated fundus examination. The data was tabulated and represented using bar diagrams, Pie charts and graphs. The results were expressed as percentages. Design-Cross-sectional, observational study. RESULTS 66 boys and 46 girls (total 112 were evaluated. The mean age of the study population was 7.8 years ± 2.4 SD. The aetiology of developmental delay was cerebral palsy (64%, Down syndrome (22%, autism (7%, intellectual disability (4.5% and 1 case each of congenital hypothyroidism and ataxia telangiectasia. The prevalence of ocular disorders was found to be 84.8%, which was slightly higher in girls (87% as compared to boys (83%. Refractive error (79.5% was the commonest ocular disorder followed by strabismus (46.4%. Astigmatism (44.6% was the commonest refractive error, which was divided into myopic astigmatism (19.6%, hyperopic astigmatism (13.8% and mixed astigmatism (11.2%. Simple hyperopia was seen in 21.9% subjects and simple myopia in 12.1%. Exotropia (52% was commoner than esotropia (48%. Other ocular abnormalities included optic atrophy, nystagmus, epicanthal folds, cataract, mongoloid slant, ptosis, telecanthus, conjunctival telangiectasia and

  16. Carbon monoxide-induced delayed amnesia, delayed neuronal death and change in acetylcholine concentration in mice

    International Nuclear Information System (INIS)

    Nabeshima, T.; Katoh, A.; Ishimaru, H.; Yoneda, Y.; Ogita, K.; Murase, K.; Ohtsuka, H.; Inari, K.; Fukuta, T.; Kameyama, T.

    1991-01-01

    We investigated the interrelationship of delayed amnesia, delayed neuronal death and changes in acetylcholine concentration induced by carbon monoxide (CO)-exposure in mice. In the test for retention of the passive avoidance task, amnesia was observed 5 and 7 days after CO-exposure when the mice were exposed to CO 1 day after training; in the case when the mice were exposed to CO 5 and 7 days before training, amnesia was also observed in a retention test given 1 day after training. The number of pyramidal cells in the hippocampal CA1 subfield was lower than that of the control 3, 5 and 7 days after CO-exposure. But the neurodegeneration in the parietal cortex, area 1, was not observed until 7 days after CO-exposure. The findings indicated that the amnesia and the neuronal death were produced after a delay when the mice were exposed to CO. In addition, the delayed amnesia was closely related to the delayed neuronal death in the hippocampal CA1 subfield. Moreover, [3H]glutamate and [3H]glycine binding sites did not change after CO-exposure but, 7 days after CO-exposure, the concentration of acetylcholine and the binding of [3H]quinuclidinyl benzilate in the frontal cortex and the striatum were found to have significantly changed, but those in the hippocampus did not show significant change. Therefore, we suggest that delayed amnesia induced by CO-exposure may result from delayed neuronal death in the hippocampal CA1 subfield and dysfunction in the acetylcholinergic neurons, in the frontal cortex, the striatum and/or the hippocampus

  17. Carbon monoxide-induced delayed amnesia, delayed neuronal death and change in acetylcholine concentration in mice

    Energy Technology Data Exchange (ETDEWEB)

    Nabeshima, T.; Katoh, A.; Ishimaru, H.; Yoneda, Y.; Ogita, K.; Murase, K.; Ohtsuka, H.; Inari, K.; Fukuta, T.; Kameyama, T. (Meijo Univ., Nagoya (Japan))

    1991-01-01

    We investigated the interrelationship of delayed amnesia, delayed neuronal death and changes in acetylcholine concentration induced by carbon monoxide (CO)-exposure in mice. In the test for retention of the passive avoidance task, amnesia was observed 5 and 7 days after CO-exposure when the mice were exposed to CO 1 day after training; in the case when the mice were exposed to CO 5 and 7 days before training, amnesia was also observed in a retention test given 1 day after training. The number of pyramidal cells in the hippocampal CA1 subfield was lower than that of the control 3, 5 and 7 days after CO-exposure. But the neurodegeneration in the parietal cortex, area 1, was not observed until 7 days after CO-exposure. The findings indicated that the amnesia and the neuronal death were produced after a delay when the mice were exposed to CO. In addition, the delayed amnesia was closely related to the delayed neuronal death in the hippocampal CA1 subfield. Moreover, (3H)glutamate and (3H)glycine binding sites did not change after CO-exposure but, 7 days after CO-exposure, the concentration of acetylcholine and the binding of (3H)quinuclidinyl benzilate in the frontal cortex and the striatum were found to have significantly changed, but those in the hippocampus did not show significant change. Therefore, we suggest that delayed amnesia induced by CO-exposure may result from delayed neuronal death in the hippocampal CA1 subfield and dysfunction in the acetylcholinergic neurons, in the frontal cortex, the striatum and/or the hippocampus.

  18. Multiple Lines of Evidence

    Energy Technology Data Exchange (ETDEWEB)

    Amidan, Brett G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Venzin, Alexander M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bramer, Lisa M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-06-03

    This paper discusses the process of identifying factors that influence the contamination level of a given decision area and then determining the likelihood that the area remains unacceptable. This process is referred to as lines of evidence. These lines of evidence then serve as inputs for the stratified compliance sampling (SCS) method, which requires a decision area to be divided into strata based upon contamination expectations. This is done in order to focus sampling efforts more within stratum where contamination is more likely and to use the domain knowledge about these likelihoods of the stratum remaining unacceptable to buy down the number of samples necessary, if possible. Two different building scenarios were considered as an example (see Table 3.1). SME expertise was elicited concerning four lines of evidence factors (see Table 3.2): 1) amount of contamination that was seen before decontamination, 2) post-decontamination air sampling information, 3) the applied decontaminant information, and 4) the surface material. Statistical experimental design and logistic regression modelling were used to help determine the likelihood that example stratum remained unacceptable for a given example scenario. The number of samples necessary for clearance was calculated by applying the SCS method to the example scenario, using the estimated likelihood of each stratum remaining unacceptable as was determined using the lines of evidence approach. The commonly used simple random sampling (SRS) method was also used to calculate the number of samples necessary for clearance for comparison purposes. The lines of evidence with SCS approach resulted in a 19% to 43% reduction in total number of samples necessary for clearance (see Table 3.6). The reduction depended upon the building scenario, as well as the level of percent clean criteria. A sensitivity analysis was also performed showing how changing the estimated likelihoods of stratum remaining unacceptable affect the number

  19. The effective delayed neutron fraction for bare-metal criticals

    International Nuclear Information System (INIS)

    Pearlstein, S.

    1999-01-01

    Given sufficient material, a large number of actinides could be used to form bare-metal criticals. The effective delayed neutron fraction for a bare critical comprised of a fissile material is comparable with the absolute delayed neutron fraction. The effective delayed neutron fraction for a bare critical composed of a fissionable material is reduced by factors of 2 to 10 when compared with the absolute delayed neutron fraction. When the effective delayed neutron fraction is small, the difference between delayed and prompt criticality is small, and extreme caution must be used in critical assemblies of these materials. This study uses an approximate but realistic model to survey the actinide region to compare effective delayed neutron fractions with absolute delayed neutron fractions

  20. ALMOST PERIODIC SOLUTIONS TO SOME NONLINEAR DELAY DIFFERENTIAL EQUATION

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The existence of an almost periodic solutions to a nonlinear delay diffierential equation is considered in this paper. A set of sufficient conditions for the existence and uniqueness of almost periodic solutions to some delay diffierential equations is obtained.