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Sample records for strongest radiating band

  1. Gamma band plasticity in sensory cortex is a signature of the strongest memory rather than memory of the training stimulus.

    Science.gov (United States)

    Weinberger, Norman M; Miasnikov, Alexandre A; Bieszczad, Kasia M; Chen, Jemmy C

    2013-09-01

    Gamma oscillations (∼30-120Hz) are considered to be a reflection of coordinated neuronal activity, linked to processes underlying synaptic integration and plasticity. Increases in gamma power within the cerebral cortex have been found during many cognitive processes such as attention, learning, memory and problem solving in both humans and animals. However, the specificity of gamma to the detailed contents of memory remains largely unknown. We investigated the relationship between learning-induced increased gamma power in the primary auditory cortex (A1) and the strength of memory for acoustic frequency. Adult male rats (n=16) received three days (200 trials each) of pairing a tone (3.66 kHz) with stimulation of the nucleus basalis, which implanted a memory for acoustic frequency as assessed by associatively-induced disruption of ongoing behavior, viz., respiration. Post-training frequency generalization gradients (FGGs) revealed peaks at non-CS frequencies in 11/16 cases, likely reflecting normal variation in pre-training acoustic experiences. A stronger relationship was found between increased gamma power and the frequency with the strongest memory (peak of the difference between individual post- and pre-training FGGs) vs. behavioral responses to the CS training frequency. No such relationship was found for the theta/alpha band (4-15 Hz). These findings indicate that the strength of specific increased neuronal synchronization within primary sensory cortical fields can determine the specific contents of memory. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Free electron broad-band THz radiator

    CERN Document Server

    Doria, A; Giovenale, E

    2002-01-01

    In this paper, a comparison between the conventional Tera-Hertz (THz) sources and a THz radiator based on free electron devices is proposed. The basic idea of the exploitation of some of the features of the RF FELs will be presented together with some examples that could represent an appealing source to start with. A discussion about the link between the spectrum of the emitted radiation and the electron bunch length is presented. The necessity of generating very short bunch of electrons to be injected in the radiator is demonstrated.

  3. A K/Ka band radiating element for Tx/Rx phased array

    KAUST Repository

    Sandhu, Ali Imran

    2017-01-20

    The paper presents a K/Ka band radiating element for TX/RX phased arrays. Dual band operations is obtained using a single radiating surface: a novel radiator is adopted and placed in a configuration in which dual band and single band elements are interleaved. The array elements are optimized to scan the beam in excess of 50° in both bands. A subarray with 49 Rx elements and 105 Tx elements was built and measured confirming the results obtained in simulations.

  4. The strongest magnetic fields in the universe

    CERN Document Server

    Balogh, A; Falanga, M; Lyutikov, M; Mereghetti, S; Piran, T; Treumann, RA

    2016-01-01

    This volume extends the ISSI series on magnetic fields in the Universe into the domain of what are by far the strongest fields in the Universe, and stronger than any field that could be produced on Earth. The chapters describe the magnetic fields in non-degenerate strongly magnetized stars, degenerate stars (such as white dwarfs and neutron stars), exotic members called magnetars, and in their environments, as well as magnetic fields in the environments of black holes. These strong fields have a profound effect on the behavior of matter, visible in particular in highly variable processes like radiation in all known wavelengths, including Gamma-Ray bursts. The generation and structure of such strong magnetic fields and effects on the environment are also described.

  5. Narrow band vacuum ultraviolet radiation, produced by fast conical discharge

    Science.gov (United States)

    Antsiferov, P. S.; Dorokhin, L. A.; Koshelev, K. N.

    2018-04-01

    The article presents the experimental study of discharges in a conical cavity, filled with Ar at pressure 80 Pa. The electrical current driver (inductive storage with plasma erosion opening switch) supplies to the load electrical current pulse with growth rate about 1012 A s‑1 and maximal value 30–40 kA. The convergent conical shock wave starts from the inner surface of the discharge cavity and collapses in ‘zippering’ mode. The pin hole camera imaging with MCP detector (time resolution 5 ns) have demonstrated the appearance of effectively fast moving compact plasma with visible velocity v  =  (1.5  ±  0.14)  ×  107 cm s‑1. Plasma emits narrow band radiation in the spectral range of Rydberg series transitions of Ar VII, Ar VIII with quantum number up to n  =  9 (wavelength about 11 nm). The intensity of radiation is comparable with the total plasma emission in the range 10–50 nm. Charge exchange between multiply charged Ar ions and cold Ar atoms of working gas is proposed as the possible mechanism of the origin of the radiation.

  6. Radiating Elements for Shared Aperture Tx/Rx Phased Arrays at K/Ka Band

    KAUST Repository

    Sandhu, Ali Imran

    2016-04-11

    A dual band, Tx/Rx, self-diplexing phased array is presented. The antenna has been designed to cover Tx/Rx satellite communications at K/Ka band with a frequency ratio 1.5:1. To obtain dual band operations with a single radiating surface, a novel dual band radiator is adopted and placed in a configuration in which dual band and single band elements are interleaved. The proposed configuration reduces the number of radiating elements required by other solutions while avoiding the insurgence of grating lobes. The tightly packed arrangement of the elements poses many integration issues, which are solved with a novel integration technique. The array elements are optimized to scan the beam in excess of ° in both bands. A subarray with 49 Rx elements and 105 Tx elements was built and measured confirming the results obtained in simulations.

  7. Occurrence features of simultaneous H+- and He+-band EMIC emissions in the outer radiation belt

    Science.gov (United States)

    Fu, Song; He, Fengming; Gu, Xudong; Ni, Binbin; Xiang, Zheng; Liu, Jiang

    2018-04-01

    As an important loss mechanism of radiation belt electrons, electromagnetic ion cyclotron (EMIC) waves show up as three distinct frequency bands below the hydrogen (H+), helium (He+), and oxygen (O+) ion gyrofrequencies. Compared to O+-band EMIC waves, H+- and He+-band emissions generally occur more frequently and result in more efficient scattering removal of understanding the evolution of the relativistic electron population. To evaluate the occurrence pattern and wave properties of H+- and He+-band EMIC waves when they occur concurrently, we investigate 64 events of multi-band EMIC emissions identified from high quality Van Allen Probes wave data. Our quantitative results demonstrate a strong occurrence dependence of the multi-band EMIC emissions on magnetic local time (MLT) and L-shell to mainly concentrate on the dayside region of L = ∼4-6. We also find that the average magnetic field amplitude of H+-band waves is larger than that of He+-band waves only when L 2 nT He+-band amplitude, indicating that the He+-band waves can be more easily amplified than the H+-band waves under the same circumstances. For simultaneous occurrences of the two EMIC wave bands, their frequencies vary with L-shell and geomagnetic activity: the peak wave frequency of H+-band emissions varies between 0.25 and 0.8 fcp with the average between 0.25 and 0.6 fcp, while that of He+-band emissions varies between 0.03 and 0.23 fcp with the average between 0.05 and 0.15 fcp. These newly observed occurrence features of simultaneous H+- and He+-band EMIC emissions provide improved information to quantify the overall contribution of multi-band EMIC waves to the loss processes of radiation belt electrons.

  8. The influence of solar radiation on radio signal at UHF band ...

    African Journals Online (AJOL)

    One of the common threats to earth-space communication is the data losss, which is possibly caused by weather factors. In this paper, the effect of solar radiation on radio signal at ultra-high frequency (UHF) band is investigated. The average radio frequencies found at UHF band were 382.5 MHz, 945.0 MHz, 1800.0 MHz, ...

  9. Mitigation of Unwanted Forward Narrow-band Radiation from PCBs with a Metamaterial Unit Cell

    DEFF Research Database (Denmark)

    Ruaro, Andrea; Thaysen, Jesper; Jakobsen, Kaj Bjarne

    2013-01-01

    Mitigation of EMI from a PCB is obtained through the use of a metamaterial unit cell. The focus is on the reduction of narrow-band radiation in the forward hemisphere when the resonant element is etched on a layer located between the source of radiation and the ground plane. As opposed to previous...

  10. X-band Linac for a 6 MeV dual-head radiation therapy gantry

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Hyun; Shin, Seung-Wook; Lee, Jongchul; Kim, Hui-Su [WCU Department of Energy Science, Suwon 440-746 (Korea, Republic of); Lee, Byeong-No; Lee, Byung-Chul [Radiation Instrumentation Research Division, Korea Atomic Energy Research Institute, Jeongeup 56212 (Korea, Republic of); Park, Hyung-dal; Song, Ki-back [Radiation Technology eXcellence (RTX), Daejeon 305-500 (Korea, Republic of); Song, Ho-seung; Mun, Sangchul; Ha, Donghyup [School of Information and Communication Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Chai, Jong-Seo, E-mail: jschai@skku.edu [School of Information and Communication Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2017-04-21

    We developed a design for a 6 MeV X-band linear accelerator for radiation therapy in a dual-head gantry layout. The dual-head gantry has two linacs that can be operated independently. Each X-band linac accelerates electron bunches using high-power RF and generates X-rays for radiation therapy. It requires a versatile RF system and pulse sequence to accomplish various radiation therapy procedures. The RF system consists of 9.3 GHz, 2 MW X-band magnetron and associated RF transmission components. A test linac was assembled and operated to characterize its RF performance without beam. This paper presents these results along with a description of the gantry linacs and their operational requirements.

  11. Isotope effect on band gap and radiative transitions properties of boron nitride nanotubes.

    Science.gov (United States)

    Han, Wei-Qiang; Yu, Hua-Gen; Zhi, Chunyi; Wang, Jianbin; Liu, Zhenxian; Sekiguchi, Takashi; Bando, Yoshio

    2008-02-01

    We have carried out an isotope study on the band gap and radiative transition spectra of boron nitride nanotubes (BNNTs) using both experimental and theoretical approaches. The direct band gap of BNNTs was determined at 5.38 eV, independent of the nanotube size and isotope substitution, by cathodoluminescences (CL) spectra. At lower energies, several radiative transitions were observed, and an isotope effect was revealed. In particular, we confirmed that the rich CL spectra between 3.0 and 4.2 eV reflect a phonon-electron coupling mechanism, which is characterized by a radiative transition at 4.09 eV. The frequency red shift and peak broadening due to isotopic effect have been observed. Our Fourier transform infrared spectra and density functional theory calculations suggest that those radiative transitions in BNNTs could be generated by a replacement of some nitrogen atoms with oxygen.

  12. Experimental investigation of 1 GW repeatable ultra-wide band pulse radiating source

    International Nuclear Information System (INIS)

    Meng Fanbao; Ma Hongge; Zhou Chuanming; Yang Zhoubing; Lu Wei; Ju Bingquan; Yu Huilong

    2001-01-01

    The single cycle pulse of 1.6 GW peak power with 20 Hz repetition-rate was generated. It radiated a peak power of more than 500 MW with a coaxial biconical antenna. The technological problems of the insulation and energy loss during generating and radiating high peak power ultra-wide band (UWB) pulse have been resolved. The experiments show that the material insulation and dispersion in sub-nanosecond pulse should be investigated deeply

  13. The Strongest Magnetic Field in Sunspots

    Science.gov (United States)

    Okamoto, J.; Sakurai, T.

    2017-12-01

    Sunspots are concentrations of magnetic fields on the solar surface. Generally, the strongest magnetic field in each sunspot is located in the dark umbra in most cases. A typical field strength in sunspots is around 3,000 G. On the other hand, some exceptions also have been found in complex sunspots with bright regions such as light bridges that separate opposite polarity umbrae, for instance with a strength of 4,300 G. However, the formation mechanism of such strong fields outside umbrae is still puzzling. Here we report an extremely strong magnetic field in a sunspot, which was located in a bright region sandwiched by two opposite-polarity umbrae. The strength is 6,250 G, which is the largest ever observed since the discovery of magnetic field on the Sun in 1908 by Hale. We obtained 31 scanned maps of the active region observed by Hinode/SOT/SP with a cadence of 3 hours over 5 days (February 1-6, 2014). Considering the spatial and temporal evolution of the vector magnetic field and the Doppler velocity in the bright region, we suggested that this strong field region was generated as a result of compression of one umbra pushed by the outward flow from the other umbra (Evershed flow), like the subduction of the Earth's crust in plate tectonics.

  14. [Influence of measurement errors of radiation in NIR bands on water atmospheric correction].

    Science.gov (United States)

    Xu, Hua; Li, Zheng-Qiang; Yin, Qiu; Gu, Xing-Fa

    2013-07-01

    For standard algorithm of atmospheric correction of water, the ratio of two near-infrared (NIR) channels is selected to determine an aerosol model, and then aerosol radiation at every wavelength is accordingly estimated by extrapolation. The uncertainty of radiation measurement in NIR bands will play important part in the accuracy of water-leaving reflectance. In the present research, erroneous expressions were derived mathematically in order to see the error propagation from NIR bands. The errors distribution of water-leaving reflectance was thoroughly studied. The results show that the bigger the errors of measurement are made, the bigger the errors of water-leaving reflectance are retrieved, with sometimes the NIR band errors canceling out. Moreover, the higher the values of aerosol optical depth or the more the component of small particles in aerosol, the bigger the errors that appear during retrieval.

  15. Transmission and radiation of an accelerating mode in a photonic band-gap fiber

    Directory of Open Access Journals (Sweden)

    C.-K. Ng

    2010-12-01

    Full Text Available A hollow-core photonic band-gap (PBG lattice in a dielectric fiber has been proposed as a high-gradient low-cost particle accelerator operating in the optical regime where the accelerating mode confined to a defect in the PBG fiber can be excited by high-power lasers [X. Lin, Phys. Rev. ST Accel. Beams 4, 051301 (2001PRABFM1098-440210.1103/PhysRevSTAB.4.051301]. Developing efficient methods of coupling laser power into these structures requires a thorough examination of the propagating mode and its near and far-field radiation. In this paper, we develop a simulation method using the parallel finite-element electromagnetic suite ACE3P to calculate the radiation of the propagating accelerator mode into free space at the end of the fiber. The far-field radiation will be calculated and the mechanism of coupling power from an experimental laser setup will be discussed.

  16. Investigation into the Effects of VHF and UHF Band Radiation on Hewlett-Packard (HP) Cesium Beam Frequency Standards

    National Research Council Canada - National Science Library

    Dickens, Andrew

    1994-01-01

    This paper documents an investigation into reports which have indicated that exposure to VHF and UHF band radiation has adverse effects on the frequency stability of HP cesium beam frequency standards...

  17. A Dual Band Additively Manufactured 3D Antenna on Package with Near-Isotropic Radiation Pattern

    KAUST Repository

    Su, Zhen

    2018-04-06

    Internet of things (IoT) applications need wireless connectivity on devices with very small footprints, and in RF obscure environments. The antenna for such applications must work on multiple GSM bands (preferred choice for network connectivity), provide near isotropic radiation pattern to maintain orientation insensitive communication, be small in size so that it can be integrated with futuristic miniaturized IoT devices, and be low in cost to be implemented on billions of devices. This paper presents a novel 3D dual band near-isotropic wideband GSM antenna to fulfill these requirements. The antenna has been realized on the package of electronics through additive manufacturing to ensure efficient utilization of available space and lower cost. The proposed antenna consists of a meander line antenna that is folded on the faces of a 3D package with two variations, 0.375λ length for narrowband version and 0.67λ length for the wideband version. Theoretical conditions to achieve near isotropic radiation pattern with bent wire antennas on a 3D surface have been derived. The antenna has been optimized to operate with embedded electronics and a large metallic battery. The antenna provides 8.9% and 34.4% bandwidths, at 900 and 1800 MHz respectively with decent near isotropic radiation behavior.

  18. Embedded top-coat for reducing the effect out of band radiation in EUV lithography

    Science.gov (United States)

    Du, Ke; Siauw, Meiliana; Valade, David; Jasieniak, Marek; Voelcker, Nico; Trefonas, Peter; Thackeray, Jim; Blakey, Idriss; Whittaker, Andrew

    2017-03-01

    Out of band (OOB) radiation from the EUV source has significant implications for the performance of EUVL photoresists. Here we introduce a surface-active polymer additive, capable of partitioning to the top of the resist film during casting and annealing, to protect the underlying photoresist from OOB radiation. Copolymers were prepared using reversible addition-fragmentation chain transfer (RAFT) polymerization, and rendered surface active by chain extension with a block of fluoro-monomer. Films were prepared from the EUV resist with added surface-active Embedded Barrier Layer (EBL), and characterized using measurements of contact angles and spectroscopic ellipsometry. Finally, the lithographic performance of the resist containing the EBL was evaluated using Electron Beam Lithography exposure

  19. Ultraviolet out-of-band radiation studies in laser tin plasma sources

    Science.gov (United States)

    Parchamy, Homaira; Szilagyi, John; Masnavi, Majid; Richardson, Martin

    2017-11-01

    Out-of-band long wavelength emission measurements from high power, high-repetition-rate extreme-ultra-violet lithography (EUVL) laser plasma sources are imperative to estimating heat deposition in EUV mirrors, and the impact of short wavelength light transported through the imaging system to the wafer surface. This paper reports a series of experiments conducted to measure the absolute spectral irradiances of laser-plasmas produced from planar tin targets over the wavelength region of 124 to 164 nm by 1.06 μm wavelength, 10 ns full-width-at-half-maximum Gaussian laser pulses. The use of spherical targets is relevant to the EUVL source scenario. Although plasmas produced from planar surfaces evolve differently, there is a close similarity to the evolution of current from 10.6 μm CO2 laser EUVL sources, which use a pre-pulse from a lower energy solid-state laser to melt and reform an initial spherical droplet into a thin planar disc target. The maximum of radiation conversion efficiency in the 124-164 nm wavelength band (1%/2πsr) occurs at the laser intensity of 1010 W cm-2. A developed collisional-radiative model reveals the strong experimental spectra that originate mainly from the 4d105p2-4d105s5p, 4d105p-4d105s resonance lines, and 4d95p-4d95s unresolved transition arrays from Sn III, Sn IV, and Sn V ions, respectively. The calculated conversion efficiencies using a 2D radiation-hydrodynamics model are in agreement with the measurements. The model predicts the out-of-band (100-400 nm) radiation conversion efficiencies generated by both 1.06 and 10.6 μm pulses. The 10.6 μm laser pulse produces a higher conversion efficiency (12%/2πsr) at the lower laser intensity of 109 W cm-2.

  20. Collisional and infrared radiative pumping of molecular vibrational states - The carbon monoxide infrared bands

    Science.gov (United States)

    Scoville, N. Z.; Krotkov, R.; Wang, D.

    1980-09-01

    An analysis of the nonlocal thermodynamic equilibrium resulting from collisions, direct pumping of infrared radiation, and UV fluorescence was made to identify the observational 'signatures' and estimate the efficiency of each process in production of vibrational line protons. The relative populations of the vibrational levels are characterized by a single excitation temperature for all modes of excitation; this is shown by the solution of the full rate equations governing the statistical equilibrium of the CO level populations. The high emissivities estimated for the CO IR band indicate that CO will dominate over H2 in the cooling of high-temperature molecular gas at densities above 10 to the 7th/cu cm; such conditions occur in a shock-heated gas in the cores of molecular clouds or in protostellar nebulae.

  1. Spaceflight Ka-Band High-Rate Radiation-Hard Modulator

    Science.gov (United States)

    Jaso, Jeffery M.

    2011-01-01

    A document discusses the creation of a Ka-band modulator developed specifically for the NASA/GSFC Solar Dynamics Observatory (SDO). This flight design consists of a high-bandwidth, Quadriphase Shift Keying (QPSK) vector modulator with radiation-hardened, high-rate driver circuitry that receives I and Q channel data. The radiationhard design enables SDO fs Ka-band communications downlink system to transmit 130 Mbps (300 Msps after data encoding) of science instrument data to the ground system continuously throughout the mission fs minimum life of five years. The low error vector magnitude (EVM) of the modulator lowers the implementation loss of the transmitter in which it is used, thereby increasing the overall communication system link margin. The modulator comprises a component within the SDO transmitter, and meets the following specifications over a 0 to 40 C operational temperature range: QPSK/OQPSK modulator, 300-Msps symbol rate, 26.5-GHz center frequency, error vector magnitude less than or equal to 10 percent rms, and compliance with the NTIA (National Telecommunications and Information Administration) spectral mask.

  2. Investigation into the effects of VHF and UHF band radiation on Hewlett-Packard (HP) Cesium Beam Frequency Standards

    Science.gov (United States)

    Dickens, Andrew

    1995-01-01

    This paper documents an investigation into reports which have indicated that exposure to VHF and UHF band radiation has adverse effects on the frequency stability of HP cesium beam frequency standards. Tests carried out on the basis of these reports show that sources of VHF and UHF radiation such as two-way hand held police communications devices do cause reproducible adverse effects. This investigation examines reproducible effects and explores possible causes.

  3. mBAND analysis for high- and low-LET radiation-induced chromosome aberrations: A review

    Energy Technology Data Exchange (ETDEWEB)

    Hada, Megumi, E-mail: megumi.hada-1@nasa.gov [NASA Johnson Space Center, Houston, TX 77058 (United States); Universities Space Research Association, Houston, TX 77058 (United States); Wu Honglu; Cucinotta, Francis A. [NASA Johnson Space Center, Houston, TX 77058 (United States)

    2011-06-03

    During long-term space travel or cancer therapy, humans are exposed to high linear energy transfer (LET) energetic heavy ions. High-LET radiation is much more effective than low-LET radiation in causing various biological effects, including cell inactivation, genetic mutations, cataracts and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, and cytogenetic damage can be utilized as a biomarker for radiation insults. Epidemiological data, mainly from survivors of the atomic bomb detonations in Japan, have enabled risk estimation from low-LET radiation exposures. The identification of a cytogenetic signature that distinguishes high- from low-LET exposure remains a long-term goal in radiobiology. Recently developed fluorescence in situ hybridization (FISH)-painting methodologies have revealed unique endpoints related to radiation quality. Heavy-ions induce a high fraction of complex-type exchanges, and possibly unique chromosome rearrangements. This review will concentrate on recent data obtained with multicolor banding in situ hybridization (mBAND) methods in mammalian cells exposed to low- and high-LET radiations. Chromosome analysis with mBAND technique allows detection of both inter- and intrachromosomal exchanges, and also distribution of the breakpoints of aberrations.

  4. Conduction mechanism in Polyaniline-flyash composite material for shielding against electromagnetic radiation in X-band & Ku band

    Directory of Open Access Journals (Sweden)

    Avanish Pratap Singh

    2011-06-01

    Full Text Available β–Naphthalene sulphonic acid (β–NSA doped polyaniline (PANI–flyash (FA composites have been prepared by chemical oxidative polymerization route whose conductivity lies in the range 2.37–21.49 S/cm. The temperature dependence of electrical conductivity has also been recorded which shows that composites follow Mott's 3D–VRH model. SEM images demonstrate that β–NSA leads to the formation of the tubular structure with incorporated flyash phase. TGA studies show the improvement in thermal stability of composites with increase in loading level of flyash. Complex parameters i.e. permittivity (ɛ* = ɛ′- iɛ″ and permeability (μ*=μ′- iμ″ of PANI-FA composites have been calculated from experimental scattering parameters (S11 & S21 using theoretical calculations given in Nicholson–Ross and Weir algorithms. The microwave absorption properties of the composites have been studied in X-band (8.2 – 12.4 GHz & Ku–Band (12.4 – 18 GHz frequency range. The maximum shielding effectiveness observed was 32dB, which strongly depends on dielectric loss and volume fraction of flyash in PANI matrix.

  5. Wide-banded NTC radiation: local to remote observations by the four Cluster satellites

    Directory of Open Access Journals (Sweden)

    P. M. E. Décréau

    2015-10-01

    Full Text Available The Cluster multi-point mission offers a unique collection of non-thermal continuum (NTC radio waves observed in the 2–80 kHz frequency range over almost 15 years, from various view points over the radiating plasmasphere. Here we present rather infrequent case events, such as when primary electrostatic sources of such waves are embedded within the plasmapause boundary far from the magnetic equatorial plane. The spectral signature of the emitted electromagnetic waves is structured as a series of wide harmonic bands within the range covered by the step in plasma frequency encountered at the boundary. Developing the concept that the frequency distance df between harmonic bands measures the magnetic field magnitude B at the source (df = Fce, electron gyrofrequency, we analyse three selected events. The first one (studied in Grimald et al., 2008 presents electric field signatures observed by a Cluster constellation of small size (~ 200 to 1000 km spacecraft separation placed in the vicinity of sources. The electric field frequency spectra display frequency peaks placed at frequencies fs = n df (n being an integer, with df of the order of Fce values encountered at the plasmapause by the spacecraft. The second event, taken from the Cluster tilt campaign, leads to a 3-D view of NTC waves ray path orientations and to a localization of a global source region at several Earth radii (RE from Cluster (Décréau et al., 2013. The measured spectra present successive peaks placed at fs ~ (n+ 1/2 df. Next, considering if both situations might be two facets of the same phenomenon, we analyze a third event. The Cluster fleet, configured into a constellation of large size (~ 8000 to 25 000 km spacecraft separation, allows us to observe wide-banded NTC waves at different distances from their sources. Two new findings can be derived from our analysis. First, we point out that a large portion of the plasmasphere boundary layer, covering a large range of magnetic

  6. Observation of coherently enhanced tunable narrow-band terahertz transition radiation from a relativistic sub-picosecond electron bunch train

    International Nuclear Information System (INIS)

    Piot, P.; Maxwell, T. J.; Sun, Y.-E; Ruan, J.; Lumpkin, A. H.; Thurman-Keup, R.; Rihaoui, M. M.

    2011-01-01

    We experimentally demonstrate the production of narrow-band (δf/f≅20% at f≅0.5THz) transition radiation with tunable frequency over [0.37, 0.86] THz. The radiation is produced as a train of sub-picosecond relativistic electron bunches transits at the vacuum-aluminum interface of an aluminum converter screen. The bunch train is generated via a transverse-to-longitudinal phase space exchange technique. We also show a possible application of modulated beams to extend the dynamical range of a popular bunch length diagnostic technique based on the spectral analysis of coherent radiation.

  7. Small radiation field dosimetry with 2-methylalanine miniature dosimeters at K-band electron paramagnetic resonance

    International Nuclear Information System (INIS)

    Chen, F.; Guzman Calcina, C.S.; Almeida, A. de; Almeida, C.E. de; Baffa, O.

    2007-01-01

    Minidosimeters of 2-methyalanine (2MA) with millimeter dimensions were produced and tested for small radiation field dosimetry. Their performance was assessed by measuring the relative output factor (ROF), beam profile (BP) and penumbra width values and were determined for square fields of 0.5x0.5, 1x1, 3x3, 5x5 and 10x10cm 2 . These results were compared with those obtained for Kodak X-Omat V radiographic film. The 2MA minidosimeters (mini2MA) were irradiated with 6 MV X-rays Varian/Clinac 2100 linear accelerator with SSD of 100 cm and depth of 1.5 cm (depth for build-up equilibrium). EPR measurements were made with a K-Band (24 GHz) spectrometer. The ROF and BP results demonstrate that the dimensions of the mini2MA are adequate for the field sizes used in this experiment. The results for penumbra width indicate that the spatial resolution of the mini2MA is comparable with that of radiographic film

  8. Toward a High-Efficient Utilization of Solar Radiation by Quad-Band Solar Spectral Splitting

    OpenAIRE

    Cao, Feng; Tang, Lu; Sun, Tianyi; Ren, Zhifeng; Huang, Yi; Boriskina, Svetlana V; Chen, Gang

    2016-01-01

    The promising quad-band solar spectral splitter incorporates the properties of the optical filter and the spectrally selective solar thermal absorber can direct PV band to PV modules and absorb thermal band energy for thermal process with low thermal losses. It provides a new strategy for spectral splitting and offers potential ways for hybrid PVT system design.

  9. Salomon: '97 E and P looking strongest in 9 years

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    Based on companies' disclosed spending plans, 1997 is shaping up to be the strongest year-ahead outlook in 9 years, according to Salomon Bros. Inc. Salomon Bros.' conclusion stems from its 15th annual survey of worldwide oil and gas exploration and production spending. The survey, released last month, included 125 US independents, 97 Canadian companies, 103 companies outside the US and Canada, and 15 majors. Significantly, when the 15% growth experienced in 1996 is combined with the 1997 outlook, it represents the strongest indicator of 2-year activity in the past 15 years, said Salomon Bros. Double-digit spending growth is projected in all regions for 1997, the analyst said. Salomon Bros. said a higher percentage of companies' E and P budgets are being allocated to offshore projects, driven in part by attractive prospects, 3D seismic technology, and increased operational efficiencies

  10. Measurement of intense coherent synchrotron radiation at frequencies around 0.1 THz using the compact S-band linac

    International Nuclear Information System (INIS)

    Sei, Norihiro; Kuroda, Ryunosuke; Yasumoto, Masato; Toyokawa, Hiroyuki; Ogawa, Hiroshi; Koike, Masaki; Yamada, Kawakatsu

    2008-01-01

    We measured intense radiation from an electron bunch in a millimeter wave region using the compact S-band linac. The dependence of the radiation on the electron-bunch charge was measured with an rf detector system at frequencies around 0.1 THz and was confirmed to be a coherent synchrotron radiation (CSR). The total power of the horizontally and vertically polarized CSRs, which were extracted through the Z-cut quartz window within 1 ns, was calculated to be about 88 and 30 nJ/pulse, excluding the absorption by the window. The two-dimensional distribution of the vertically polarized CSR was measured at a distance of about 0.7 m from the radiation point. The CSR distribution was comparatively uniform in the horizontal plane. Intense CSR, which was reflected in the vacuum chamber, was extracted with a delay of about 6 ns. This suggests that measurement of temporal structure is needed for CSR applications

  11. Arctic sea ice signatures: L-band brightness temperature sensitivity comparison using two radiation transfer models

    Directory of Open Access Journals (Sweden)

    F. Richter

    2018-03-01

    Full Text Available Sea ice is a crucial component for short-, medium- and long-term numerical weather predictions. Most importantly, changes of sea ice coverage and areas covered by thin sea ice have a large impact on heat fluxes between the ocean and the atmosphere. L-band brightness temperatures from ESA's Earth Explorer SMOS (Soil Moisture and Ocean Salinity have been proven to be a valuable tool to derive thin sea ice thickness. These retrieved estimates were already successfully assimilated in forecasting models to constrain the ice analysis, leading to more accurate initial conditions and subsequently more accurate forecasts. However, the brightness temperature measurements can potentially be assimilated directly in forecasting systems, reducing the data latency and providing a more consistent first guess. As a first step towards such a data assimilation system we studied the forward operator that translates geophysical parameters provided by a model into brightness temperatures. We use two different radiative transfer models to generate top of atmosphere brightness temperatures based on ORAP5 model output for the 2012/2013 winter season. The simulations are then compared against actual SMOS measurements. The results indicate that both models are able to capture the general variability of measured brightness temperatures over sea ice. The simulated brightness temperatures are dominated by sea ice coverage and thickness changes are most pronounced in the marginal ice zone where new sea ice is formed. There we observe the largest differences of more than 20 K over sea ice between simulated and observed brightness temperatures. We conclude that the assimilation of SMOS brightness temperatures yields high potential for forecasting models to correct for uncertainties in thin sea ice areas and suggest that information on sea ice fractional coverage from higher-frequency brightness temperatures should be used simultaneously.

  12. Arctic sea ice signatures: L-band brightness temperature sensitivity comparison using two radiation transfer models

    Science.gov (United States)

    Richter, Friedrich; Drusch, Matthias; Kaleschke, Lars; Maaß, Nina; Tian-Kunze, Xiangshan; Mecklenburg, Susanne

    2018-03-01

    Sea ice is a crucial component for short-, medium- and long-term numerical weather predictions. Most importantly, changes of sea ice coverage and areas covered by thin sea ice have a large impact on heat fluxes between the ocean and the atmosphere. L-band brightness temperatures from ESA's Earth Explorer SMOS (Soil Moisture and Ocean Salinity) have been proven to be a valuable tool to derive thin sea ice thickness. These retrieved estimates were already successfully assimilated in forecasting models to constrain the ice analysis, leading to more accurate initial conditions and subsequently more accurate forecasts. However, the brightness temperature measurements can potentially be assimilated directly in forecasting systems, reducing the data latency and providing a more consistent first guess. As a first step towards such a data assimilation system we studied the forward operator that translates geophysical parameters provided by a model into brightness temperatures. We use two different radiative transfer models to generate top of atmosphere brightness temperatures based on ORAP5 model output for the 2012/2013 winter season. The simulations are then compared against actual SMOS measurements. The results indicate that both models are able to capture the general variability of measured brightness temperatures over sea ice. The simulated brightness temperatures are dominated by sea ice coverage and thickness changes are most pronounced in the marginal ice zone where new sea ice is formed. There we observe the largest differences of more than 20 K over sea ice between simulated and observed brightness temperatures. We conclude that the assimilation of SMOS brightness temperatures yields high potential for forecasting models to correct for uncertainties in thin sea ice areas and suggest that information on sea ice fractional coverage from higher-frequency brightness temperatures should be used simultaneously.

  13. Simultaneous Out-of-band Interference Rejection and Radiation Enhancement in an Electronic Product via an EBG Structure

    DEFF Research Database (Denmark)

    Ruaro, Andrea; Thaysen, Jesper; Jakobsen, Kaj Bjarne

    2014-01-01

    This work presents an application of a planar electromagnetic band gap (EBG) structure with a perspective product implementation in the back of the mind. The focus is on the integration of such structure under the constraint of space and system coexistence. It is discovered that it is possible...... (alternatively, parallel plate noise) and decrease the radiation efficiency of the structure forbidding higher-order modes to propagate and subsequently be diffracted by the ground plane....

  14. Considering body mass differences, who are the world's strongest women?

    Science.gov (United States)

    Vanderburgh, P M; Dooman, C

    2000-01-01

    Allometric modeling (AM) has been used to determine the world's strongest body mass-adjusted man. Recently, however, AM was shown to demonstrate body mass bias in elite Olympic weightlifting performance. A second order polynomial (2OP) provided a better fit than AM with no body mass bias for men and women. The purpose of this study was to apply both AM and 2OP models to women's world powerlifting records (more a function of pure strength and less power than Olympic lifts) to determine the optimal model approach as well as the strongest body mass-adjusted woman in each event. Subjects were the 36 (9 per event) current women world record holders (as of Nov., 1997) for bench press (BP), deadlift (DL), squat (SQ), and total (TOT) lift (BP + DL + SQ) according to the International Powerlifting Federation (IPF). The 2OP model demonstrated the superior fit and no body mass bias as indicated by the coefficient of variation and residuals scatterplot inspection, respectively, for DL, SQ, and TOT. The AM for these three lifts, however, showed favorable bias toward the middle weight classes. The 2OP and AM yielded an essentially identical fit for BP. Although body mass-adjusted world records were dependent on the model used, Carrie Boudreau (U.S., 56-kg weight class), who received top scores in TOT and DL with both models, is arguably the world's strongest woman overall. Furthermore, although the 2OP model provides a better fit than AM for this elite population, a case can still be made for AM use, particularly in light of theoretical superiority.

  15. The Strength of the Strongest Ties in Collaborative Problem Solving

    DEFF Research Database (Denmark)

    de Montjoye, Yves-Alexandre; Stopczynski, Arkadiusz; Shmueli, Erez

    2014-01-01

    Complex problem solving in science, engineering, and business has become a highly collaborative endeavor. Teams of scientists or engineers collaborate on projects using their social networks to gather new ideas and feedback. Here we bridge the literature on team performance and information networks...... by studying teams' problem solving abilities as a function of both their within-team networks and their members' extended networks. We show that, while an assigned team's performance is strongly correlated with its networks of expressive and instrumental ties, only the strongest ties in both networks have......-significant in the statistical analysis. Our results have consequences for the organization of teams of scientists, engineers, and other knowledge workers tackling today's most complex problems....

  16. Ultra-wide-band accumulation of coherent undulator synchrotron radiation in a resonating cavity

    Directory of Open Access Journals (Sweden)

    Y. H. Seo

    2011-06-01

    Full Text Available Cavity accumulation of coherent undulator synchrotron radiation emitted by a train of periodic electron bunches is investigated. Phase-matching conditions for accumulation of radiation emitted by successive bunches are analyzed and numerically confirmed. While the coherent emission of a single bunch is optimal at grazing resonance, the accumulated radiation targeted at the upper resonant frequency of the waveguide mode is found to have much broader bandwidth and higher efficiency as the resonance steps away from the grazing condition. Numerical results confirm that stimulated superradiance is responsible for the accumulated radiation.

  17. Oxygen A-band Spectroscopy: An Overlooked Resource for Ground-Based Inference of Physical and Radiative Properties of Clouds

    Science.gov (United States)

    Davis, A. B.; Min, Q.; Barker, H. W.

    2011-12-01

    than one cloud layer of significance to the solar energy budget. This feature also ensures that the above-mentioned retrievals of single-layer cloud properties are reliable. As the spatial complexity of the cloudiness increases, ground-based O2 A-band spectroscopy morphs from a 1D (quasi-slab geometry) cloud remote sensing tool into a fully 3D cloud radiative property diagnostic tool. In this new capacity, O2 A-band observations can be brought to bear on the challenging issue of accurately predicting mean shortwave heating rates over large domains, as required in GCM parameterizations of fast physics. Specifically, the performance of GCM cloud and/or shortwave radiation schemes can be evaluated against O2 A-band data, once separated in to their broadband spectral integration and spatial radiation transport parts. In this presentation, we will (1) survey the published technical literature on the cloud remote sensing applications of O2 A-band spectroscopy and (2) describe the emerging ideas of how it can be used to test some key GCM physics, namely, clouds and solar radiation, at the component level. Key differences between ground- and space-based observations will be highlighted.

  18. Synchronization of radiation in an oversized coaxial Ka-band backward wave oscillator using two-dimensional Bragg structure

    Directory of Open Access Journals (Sweden)

    N. S. Ginzburg

    2015-12-01

    Full Text Available A coaxial Ka-band backward wave oscillator with a two-dimensional Bragg structure located at the output of the interaction space has been studied. This structure has a double-period corrugation and provides azimuthal electromagnetic energy fluxes, which act on the synchronized radiation of an oversized tubular electron beam. Proof-of-principle experiments were conducted based on the Saturn thermionic accelerator (300  keV/200  A/2  μs. In accordance with simulations, narrow-band generation was obtained at a frequency of 30 GHz and a power level of 1.5–2 MW. As a result, the possibility of using a two-dimensional distributed feedback mechanism in oscillators of the Cherenkov type has been demonstrated.

  19. Search for molecular bremsstrahlung radiation signals in Ku band with coincidental operations of radio telescopes with air shower detectors

    Directory of Open Access Journals (Sweden)

    Fukushima Masaki

    2013-06-01

    Full Text Available Microwave radiation from extensive air showers is expected to provide a new technique to observe UHECR. We insatlled and operate radio telescopes in Osaka and at Telescope Array site in Utah, USA. In Osaka, we are coincidentally operating two Ku band radio telescopes with an air shower array which consists of nine plastic scintillators with about 10 m separation. In Utah, we installed two telescopes just beside the Black Rock Mesa fluorescence detector (FD station of the Telescope Array experiment, and we operated the radio telescopes coincidentally with FD event triggers. We report the experimental setups and the results of these measurements.

  20. An alternative method for calibration of narrow band radiometer using a radiative transfer model

    International Nuclear Information System (INIS)

    Salvador, J; Wolfram, E; D'Elia, R; Zamorano, F; Casiccia, C; Rosales, A; Quel, E

    2011-01-01

    The continual monitoring of solar UV radiation is one of the major objectives proposed by many atmosphere research groups. The purpose of this task is to determine the status and degree of progress over time of the anthropogenic composition perturbation of the atmosphere. Such changes affect the intensity of the UV solar radiation transmitted through the atmosphere that then interacts with living organisms and all materials, causing serious consequences in terms of human health and durability of materials that interact with this radiation. One of the many challenges that need to be faced to perform these measurements correctly is the maintenance of periodic calibrations of these instruments. Otherwise, damage caused by the UV radiation received will render any one calibration useless after the passage of some time. This requirement makes the usage of these instruments unattractive, and the lack of frequent calibration may lead to the loss of large amounts of acquired data. Motivated by this need to maintain calibration or, at least, know the degree of stability of instrumental behavior, we have developed a calibration methodology that uses the potential of radiative transfer models to model solar radiation with 5% accuracy or better relative to actual conditions. Voltage values in each radiometer channel involved in the calibration process are carefully selected from clear sky data. Thus, tables are constructed with voltage values corresponding to various atmospheric conditions for a given solar zenith angle. Then we model with a radiative transfer model using the same conditions as for the measurements to assemble sets of values for each zenith angle. The ratio of each group (measured and modeled) allows us to calculate the calibration coefficient value as a function of zenith angle as well as the cosine response presented by the radiometer. The calibration results obtained by this method were compared with those obtained with a Brewer MKIII SN 80 located in the

  1. A simplified scheme for generating narrow-band mid-ultraviolet laser radiation

    International Nuclear Information System (INIS)

    Almog, G.; Scholz, M.; Weber, W.; Leisching, P.; Kaenders, W.; Udem, Th.

    2015-01-01

    We report on the development and characterization of continuous, narrow-band, and tunable laser systems that use direct second-harmonic generation from blue and green diode lasers with an output power level of up to 11.1 mW in the mid-ultraviolet. One of our laser systems was tuned to the mercury 6 1 S 0 → 6 3 P 1 intercombination line at 253.7 nm. We could perform Doppler-free saturation spectroscopy on this line and were able to lock our laser to the transition frequency on long time scales

  2. Blandford's argument: The strongest continuous gravitational wave signal

    International Nuclear Information System (INIS)

    Knispel, Benjamin; Allen, Bruce

    2008-01-01

    For a uniform population of neutron stars whose spin-down is dominated by the emission of gravitational radiation, an old argument of Blandford states that the expected gravitational-wave amplitude of the nearest source is independent of the deformation and rotation frequency of the objects. Recent work has improved and extended this argument to set upper limits on the expected amplitude from neutron stars that also emit electromagnetic radiation. We restate these arguments in a more general framework, and simulate the evolution of such a population of stars in the gravitational potential of our galaxy. The simulations allow us to test the assumptions of Blandford's argument on a realistic model of our galaxy. We show that the two key assumptions of the argument (two dimensionality of the spatial distribution and a steady-state frequency distribution) are in general not fulfilled. The effective scaling dimension D of the spatial distribution of neutron stars is significantly larger than two, and for frequencies detectable by terrestrial instruments the frequency distribution is not in a steady state unless the ellipticity is unrealistically large. Thus, in the cases of most interest, the maximum expected gravitational-wave amplitude does have a strong dependence on the deformation and rotation frequency of the population. The results strengthen the previous upper limits on the expected gravitational-wave amplitude from neutron stars by a factor of 6 for realistic values of ellipticity.

  3. Radiation losses in the microwave Ku band in magneto-electric nanocomposites

    Directory of Open Access Journals (Sweden)

    Talwinder Kaur

    2015-08-01

    Full Text Available A study on radiation losses in conducting polymer nanocomposites, namely La–Co-substituted barium hexaferrite and polyaniline, is presented. The study was performed by means of a vector network analyser, X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, electron spin resonance spectroscopy and a vibrating sample magnetometer. It is found that the maximum loss occurs at 17.9 GHz (−23.10 dB, 99% loss which is due to the composition of a conducting polymer and a suitable magnetic material. A significant role of polyaniline has been observed in ESR. The influence of the magnetic properties on the radiation losses is explained. Further studies revealed that the prepared material is a nanocomposite. FTIR spectra show the presence of expected chemical structures such as C–H bonds in a ring system at 1512 cm−1.

  4. Radiation and environmental data analysis computer (REDAC) hardware, software band analysis procedures

    International Nuclear Information System (INIS)

    Hendricks, T.J.

    1985-01-01

    The REDAC was conceived originally as a tape verifier for the Radiation and Environmental Data Acquisition Recorder (REDAR). From that simple beginning in 1971, the REDAC has evolved into a family of systems used for complete analysis of data obtained by the REDAR and other acquisition systems. Portable or mobile REDACs are deployed to support checkout and analysis tasks in the field. Laboratory systems are additionally used for software development, physics investigations, data base management and graphics. System configurations range from man-portable systems to a large laboratory-based system which supports time-shared analysis and development tasks. Custom operating software allows the analyst to process data either interactively or by batch procedures. Analysis packages are provided for numerous necessary functions. All these analysis procedures can be performed even on the smallest man-portable REDAC. Examples of the multi-isotope stripping and radiation isopleth mapping are presented. Techniques utilized for these operations are also presented

  5. Effects of gamma radiation on faba bean seed beetle Bruchus Dentipes Bande

    International Nuclear Information System (INIS)

    Mansour, Mohammed; Al-Bachir, Mahfouz

    1993-04-01

    Faba bean, Vivia bata, is one of the most important agricultural legume plants in Syria. Like any other crop, it is attacked by several insect pests. The most important of these is the faba bean seed beetle, Bruchus Dentipes Baudi. Infestation occurs only in the field and the major source of infestation is infested seed used for planting. The average infestation rate is about 45% and this reduces the economic value of the seeds to less than 50%. Chemical control in the field is effective but too expensive. Treating seeds in storage with fumigants is not as effective as it used to be, probably because of the pest developing resistance. Biological control has been investigated but their is no practically acceptable biological control agent at present. The lack of an effective biological control agent and/or economically acceptable and environmentally sound chemical control has led us to investigate the possibility of using gamma radiation to disinfest faba bean seeds as soon as possible after harvest when the insect is still in its early development stages. Infested faba bean seeds were treated immediately after harvest with 4 levels of gamma radiation ranged from 30 to 120 Gy with 30 Gy intervals. Treatment was repeated 15 and 30 days later and the effect of gamma radiation on larval survival was evaluated. The results showed that 90 Gy was sufficient to stop larval development and cause a 100% mortality. This dose, however, affected negatively seed germination. These results indicate that it is possible to disinfest faba bean seeds stored for human consumption with 90 Gy of gamma radiation. However, seeds destined for planting can not be treated with this dose. (author). 35 refs., 6 tabs., 2 figs

  6. X-Ray Emitting GHz-Peaked Spectrum Galaxies: Testing a Dynamical-Radiative Model with Broad-Band Spectra

    Energy Technology Data Exchange (ETDEWEB)

    Ostorero, L.; /Turin U. /INFN, Turin; Moderski, R.; /Warsaw, Copernicus Astron. Ctr. /KIPAC, Menlo Park; Stawarz, L.; /KIPAC, Menlo Park /Jagiellonian U., Astron. Observ.; Diaferio, A.; /Turin U. /INFN, Turin; Kowalska, I.; /Warsaw U. Observ.; Cheung, C.C.; /NASA, Goddard /Naval Research Lab, Wash., D.C.; Kataoka, J.; /Waseda U., RISE; Begelman, M.C.; /JILA, Boulder; Wagner, S.J.; /Heidelberg Observ.

    2010-06-07

    In a dynamical-radiative model we recently developed to describe the physics of compact, GHz-Peaked-Spectrum (GPS) sources, the relativistic jets propagate across the inner, kpc-sized region of the host galaxy, while the electron population of the expanding lobes evolves and emits synchrotron and inverse-Compton (IC) radiation. Interstellar-medium gas clouds engulfed by the expanding lobes, and photoionized by the active nucleus, are responsible for the radio spectral turnover through free-free absorption (FFA) of the synchrotron photons. The model provides a description of the evolution of the GPS spectral energy distribution (SED) with the source expansion, predicting significant and complex high-energy emission, from the X-ray to the {gamma}-ray frequency domain. Here, we test this model with the broad-band SEDs of a sample of eleven X-ray emitting GPS galaxies with Compact-Symmetric-Object (CSO) morphology, and show that: (i) the shape of the radio continuum at frequencies lower than the spectral turnover is indeed well accounted for by the FFA mechanism; (ii) the observed X-ray spectra can be interpreted as non-thermal radiation produced via IC scattering of the local radiation fields off the lobe particles, providing a viable alternative to the thermal, accretion-disk dominated scenario. We also show that the relation between the hydrogen column densities derived from the X-ray (N{sub H}) and radio (N{sub HI}) data of the sources is suggestive of a positive correlation, which, if confirmed by future observations, would provide further support to our scenario of high-energy emitting lobes.

  7. X-ray Emitting GHz-Peaked Spectrum Galaxies: Testing a Dynamical-Radiative Model with Broad-Band Spectra

    International Nuclear Information System (INIS)

    Ostorero, L.; Moderski, R.; Stawarz, L.; Diaferio, A.; Kowalska, I.; Cheung, C.C.; Kataoka, J.; Begelman, M.C.; Wagner, S.J.

    2010-01-01

    In a dynamical-radiative model we recently developed to describe the physics of compact, GHz-Peaked-Spectrum (GPS) sources, the relativistic jets propagate across the inner, kpc-sized region of the host galaxy, while the electron population of the expanding lobes evolves and emits synchrotron and inverse-Compton (IC) radiation. Interstellar-medium gas clouds engulfed by the expanding lobes, and photoionized by the active nucleus, are responsible for the radio spectral turnover through free-free absorption (FFA) of the synchrotron photons. The model provides a description of the evolution of the GPS spectral energy distribution (SED) with the source expansion, predicting significant and complex high-energy emission, from the X-ray to the γ-ray frequency domain. Here, we test this model with the broad-band SEDs of a sample of eleven X-ray emitting GPS galaxies with Compact-Symmetric-Object (CSO) morphology, and show that: (i) the shape of the radio continuum at frequencies lower than the spectral turnover is indeed well accounted for by the FFA mechanism; (ii) the observed X-ray spectra can be interpreted as non-thermal radiation produced via IC scattering of the local radiation fields off the lobe particles, providing a viable alternative to the thermal, accretion-disk dominated scenario. We also show that the relation between the hydrogen column densities derived from the X-ray (N H ) and radio (N HI ) data of the sources is suggestive of a positive correlation, which, if confirmed by future observations, would provide further support to our scenario of high-energy emitting lobes.

  8. Development of a wide band radiative transfer model based on a fast correlated k-distributions generation

    Science.gov (United States)

    Croize, Laurence; Pierro, Jean; Huet, Thierry; Labarre, Luc

    2016-04-01

    MATISSE which acronym means Advanced Modeling of the Earth for Environment and Scenes Simulation is developed by ONERA since the mid 1990's. The code main functionality is to compute spectral or integrated natural background radiance images. Natural backgrounds include the atmosphere, low and high altitude clouds, sea and land. It can also provide specific radiative atmospheric terms as path transmission, path radiances, sky radiances or local illumination around a target point. Spectral bandwidth ranges from 700 to 25000 cm-1 wavenumber (i.e. from 0.4 to 14 μm). As far as molecular absorption is concerned, MATISSE v2.0 is based on a correlated K (CK) model and needs a pre-generation of the k-distributions. This method is very precise but is time consuming and is done as an offline calculation. In answer to the increasing need of rapid radiative transfer codes, the future version of the MATISSE v3.0 will include a fast radiative transfer model at low and at medium spectral resolution. This work aims to develop a fast wide band CK model for the acceleration of radiative transfer calculation. As a first step, a statistical k-distributions fast generator was developed. It allows generating k-distributions from 700 to 25000 cm-1 with a spectral resolution of 1 cm-1 in less than 30 ms(*) for one altitude (that means about three orders of magnitude faster than before). Such speed allows generating k-distributions online. To validate the model, we have compared the obtained transmission spectra with reference spectra using a mix of 6 molecules (H2O, CO2, O3, N2O, CO, CH4) in homogenous atmosphere corresponding to different altitudes from 0 to 105 km. Reference spectra were calculated as the convolution of a spectrum obtained with a line by line model and a gate function of 1 cm-1 wide. An average difference of 3×10-3 % and a standard deviation of 3.3% were typically obtained. As a second step, this method of rapid k-distributions generation is now being coupled with a

  9. Uncertainty Quantification of GEOS-5 L-band Radiative Transfer Model Parameters Using Bayesian Inference and SMOS Observations

    Science.gov (United States)

    DeLannoy, Gabrielle J. M.; Reichle, Rolf H.; Vrugt, Jasper A.

    2013-01-01

    Uncertainties in L-band (1.4 GHz) radiative transfer modeling (RTM) affect the simulation of brightness temperatures (Tb) over land and the inversion of satellite-observed Tb into soil moisture retrievals. In particular, accurate estimates of the microwave soil roughness, vegetation opacity and scattering albedo for large-scale applications are difficult to obtain from field studies and often lack an uncertainty estimate. Here, a Markov Chain Monte Carlo (MCMC) simulation method is used to determine satellite-scale estimates of RTM parameters and their posterior uncertainty by minimizing the misfit between long-term averages and standard deviations of simulated and observed Tb at a range of incidence angles, at horizontal and vertical polarization, and for morning and evening overpasses. Tb simulations are generated with the Goddard Earth Observing System (GEOS-5) and confronted with Tb observations from the Soil Moisture Ocean Salinity (SMOS) mission. The MCMC algorithm suggests that the relative uncertainty of the RTM parameter estimates is typically less than 25 of the maximum a posteriori density (MAP) parameter value. Furthermore, the actual root-mean-square-differences in long-term Tb averages and standard deviations are found consistent with the respective estimated total simulation and observation error standard deviations of m3.1K and s2.4K. It is also shown that the MAP parameter values estimated through MCMC simulation are in close agreement with those obtained with Particle Swarm Optimization (PSO).

  10. The spectral invariant approximation within canopy radiative transfer to support the use of the EPIC/DSCOVR oxygen B-band for monitoring vegetation

    International Nuclear Information System (INIS)

    Marshak, Alexander; Knyazikhin, Yuri

    2017-01-01

    EPIC (Earth Polychromatic Imaging Camera) is a 10-channel spectroradiometer onboard DSCOVR (Deep Space Climate Observatory) spacecraft. In addition to the near-infrared (NIR, 780 nm) and the ‘red’ (680 nm) channels, EPIC also has the O2 A-band (764±0.2 nm) and B-band (687.75±0.2 nm). The EPIC Normalized Difference Vegetation Index (NDVI) is defined as the difference between NIR and ‘red’ channels normalized to their sum. However, the use of the O2 B-band instead of the ‘red’ channel mitigates the effect of atmosphere on remote sensing of surface reflectance because O2 reduces contribution from the radiation scattered by the atmosphere. Applying the radiative transfer theory and the spectral invariant approximation to EPIC observations, the paper provides supportive arguments for using the O2 band instead of the red channel for monitoring vegetation dynamics. Our results suggest that the use of the O2 B-band enhances the sensitivity of the top-of-atmosphere NDVI to the presence of vegetation. - Highlights: • The use of the O2 B-band channel (688 nm) instead of the red channel (680 nm) mitigates the effect of atmosphere on remote sensing of surface reflectance. • The spectral invariant approach confirms that the synergy of the green, O2 B-band and near IR channels mimics spectral properties of vegetation. • The structural parameter of vegetation retrieved remotely is weakly sensitive to the uncertainty in the atmospheric optical depth.

  11. Simulation study of CD variation caused by field edge effects and out-of-band radiation in EUVL

    Science.gov (United States)

    Gao, Weimin; Niroomand, Ardavan; Lorusso, Gian F.; Boone, Robert; Lucas, Kevin; Demmerle, Wolfgang

    2013-09-01

    Although extreme ultraviolet lithography (EUVL) remains a promising candidate for semiconductor device manufacturing of the 1x nm half pitch node and beyond, many technological burdens have to be overcome. The "field edge effect" in EUVL is one of them. The image border region of an EUV mask,also known as the "black border" (BB), reflects a few percent of the incident EUV light, resulting in a leakage of light into neighboring exposure fields, especially at the corner of the field where three adjacent exposures take place. This effect significantly impacts on CD uniformity (CDU) across the exposure field. To avoid this phenomenon, a light-shielding border is introduced by etching away the entire absorber and multi-layer (ML)at the image border region of the EUV mask. In this paper, we present a method of modeling the field edge effect (also called the BB effect) by using rigorous lithography simulation with a calibrated resist model. An additional "flare level" at the field edge is introduced on top of the exposure tool flare map to account for the BB effect. The parameters in this model include the reflectivity and the width of the BB, which are mainly determining the leakage of EUV light and its influence range, respectively. Another parameter is the transition width which represents the half shadow effect of the reticle masking blades. By setting the corresponding parameters, the simulation results match well the experimental results obtained at the imec's NXE:3100 EUV exposure tool. Moreover, these results indicate that the out-of-band (OoB) radiation also contributes to the CDU. Using simulation we can also determine the OoB effect rigorouslyusing the methodology of an "effective mask blank". The study in this paper demonstrates that the impact of BB and OoB effects on CDU can be well predicted by simulations.

  12. Study of CD variation caused by the black border effect and out-of-band radiation in extreme ultraviolet lithography

    Science.gov (United States)

    Gao, Weimin; Niroomand, Ardavan; Lorusso, Gian F.; Boone, Robert; Lucas, Kevin; Demmerle, Wolfgang

    2014-04-01

    Although extreme ultraviolet lithography (EUVL) remains a promising candidate for semiconductor device manufacturing of the 1× nm half pitch node and beyond, many technological burdens have to be overcome. The "field edge effect" in EUVL is one of them. The image border region of an EUV mask, also known as the "black border" (BB), reflects a few percent of the incident EUV light, resulting in a leakage of light into neighboring exposure fields, especially at the corner of the field where three adjacent exposures take place. This effect significantly impacts on critical dimension (CD) uniformity (CDU) across the exposure field. To avoid this phenomenon, a light-shielding border is introduced by etching away the entire absorber and multilayer at the image border region of the EUV mask. We present a method of modeling the field edge effect (also called the BB effect) by using rigorous lithography simulation with a calibrated resist model. An additional "flare level" at the field edge is introduced on top of the exposure tool flare map to account for the BB effect. The parameters in this model include the reflectivity and the width of the BB, which are mainly determining the leakage of EUV light and its influence range, respectively. Another parameter is the transition width which represents the half shadow effect of the reticle masking blades. By setting the corresponding parameters, the simulation results match well the experimental results obtained at the IMEC's NXE:3100 EUV exposure tool. Moreover, these results indicate that the out-of-band (OoB) radiation also contributes to the CDU. Using simulation, we can also determine the OoB effect rigorously using the methodology of an "effective mask blank." The study demonstrates that the impact of BB and OoB effects on CDU can be well predicted by simulations.

  13. Band-notched spiral antenna

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Jae; Chang, John

    2018-03-13

    A band-notched spiral antenna having one or more spiral arms extending from a radially inner end to a radially outer end for transmitting or receiving electromagnetic radiation over a frequency range, and one or more resonance structures positioned adjacent one or more segments of the spiral arm associated with a notch frequency band or bands of the frequency range so as to resonate and suppress the transmission or reception of electromagnetic radiation over said notch frequency band or bands.

  14. A method of retrieving cloud top height and cloud geometrical thickness with oxygen A and B bands for the Deep Space Climate Observatory (DSCOVR) mission: Radiative transfer simulations

    International Nuclear Information System (INIS)

    Yang, Yuekui; Marshak, Alexander; Mao, Jianping; Lyapustin, Alexei; Herman, Jay

    2013-01-01

    The Earth Polychromatic Imaging Camera (EPIC) onboard the Deep Space Climate Observatory (DSCOVR) was designed to measure the atmosphere and surface properties over the whole sunlit half of the Earth from the L1 Lagrangian point. It has 10 spectral channels ranging from the UV to the near-IR, including two pairs of oxygen (O 2 ) A-band (779.5 and 764 nm) and B-band (680 and 687.75 nm) reference and absorption channels selected for the cloud height measurements. This paper presents the radiative transfer analysis pertinent to retrieving cloud top height and cloud geometrical thickness with EPIC A- and B-band observations. Due to photon cloud penetration, retrievals from either O 2 A- or B-band channels alone gives the corresponding cloud centroid height, which is lower than the cloud top. However, we show both the sum and the difference between the retrieved cloud centroid heights in the A and B bands are functions of cloud top height and cloud geometrical thickness. Based on this fact, the paper develops a new method to retrieve cloud top height and cloud geometrical thickness simultaneously for fully cloudy scenes over ocean surface. First, cloud centroid heights are calculated for both A and B bands using the ratios between the reflectances of the absorbing and reference channels; then the cloud top height and the cloud geometrical thickness are retrieved from the two dimensional look up tables that relate the sum and the difference between the retrieved centroid heights for A and B bands to the cloud top height and the cloud geometrical thickness. This method is applicable for clouds thicker than an optical depth of 5. -- Highlights: ► EPIC onboard DSCOVR is equipped with O 2 A and B band channels. ► Photon cloud penetration depths of A and B bands contain information of cloud thickness. ► A method is developed to retrieve cloud top height and cloud geometrical thickness with EPIC O 2 A- and B-band

  15. Strongest Tropical cyclones: 1980-2009: A 30-year collage of Hurricane Satellite (HURSAT) data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Strongest Tropical Cyclones: 1980-2009 poster - a 30-year collage of Hurricane Satellite (HURSAT) data. This poster depicts a series of 5 degree grids where within...

  16. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Engineering Test Report: Radiated Emissions and SARR, SARP, DCS Receivers, Link Frequencies EMI Sensitive Band Test Results, AMSU-A1, S/N 108 2

    Science.gov (United States)

    Valdez, A.

    2000-01-01

    This is the Engineering Test Report, Radiated Emissions and SARR, SARP, DCS Receivers, Link Frequencies EMI Sensitive Band Test Results, AMSU-A1 SIN 108, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).

  17. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Engineering Test Report: Radiated Emissions and SARR, SARP, DCS Receivers, Link Frequencies EMI Sensitive Band Test Results, AMSU-A1, S/N 109

    Science.gov (United States)

    Valdez, A.

    2000-01-01

    This is the Engineering Test Report, Radiated Emissions and SARR, SARP, DCS Receivers, Link Frequencies EMI Sensitive Band Test Results, AMSU-A1, S/N 109, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).

  18. Integrated Advanced Microwave Sounding Unit-A (AMSU-A). Engineering Test Report: Radiated Emissions and SARR, SARP, DCS Receivers, Link Frequencies EMI Sensitive Band Test Results, AMSU-A2, S/N 108, 08

    Science.gov (United States)

    Valdez, A.

    2000-01-01

    This is the Engineering Test Report, Radiated Emissions and SARR, SARP, DCS Receivers, Link Frequencies EMI Sensitive Band Test Results, AMSU-A2, S/N 108, for the Integrated Advanced Microwave Sounding Unit-A (AMSU-A).

  19. Wide Band-Gap Semiconductor Radiation Detectors: Science Fiction, Horror Story, or Headlines (460th Brookhaven Lecture)

    International Nuclear Information System (INIS)

    James, Ralph

    2010-01-01

    With radiation constantly occurring from natural sources all around us -- from food, building materials, and rays from the sun, to name a few -- detecting radiotracers for medical procedures and other radiation to keep people safe is not easy. In order to make better use of radiation to diagnose or treat certain health conditions, or to track radiological materials being transported, stored, and used, the quest is on to develop improved radiation detectors. James gives a brief introduction on radiation detection and explain how it is used in applications ranging from medical to homeland security. He then discusses how new materials and better ways to analyze them here at the National Synchrotron Light Source (NSLS) and the future NSLS-II will lead to a new class of radiation detectors that will provide unprecedented advances in medical and industrial imaging, basic science, and the nonproliferation of nuclear materials.

  20. Circuital characteristics and radiation properties of an UWB electric-magnetic planar antenna for Ku-band applications

    NARCIS (Netherlands)

    Haider, S.N.; Caratelli, D.; Yarovoy, A.G.

    2013-01-01

    A planar, directive antenna with large fractional bandwidth is introduced in this paper. A detailed discussion on the proposed antenna topology and its architecture is reported. The proposed element is a combination of a patch and a loop radiator. A proper combination of the electric field radiator

  1. Generation of lower and upper bands of electrostatic electron cyclotron harmonic waves in the Van Allen radiation belts

    Science.gov (United States)

    Zhou, Qinghua; Xiao, Fuliang; Yang, Chang; Liu, Si; He, Yihua; Baker, D. N.; Spence, H. E.; Reeves, G. D.; Funsten, H. O.

    2017-06-01

    Electrostatic electron cyclotron harmonic (ECH) waves generated by the electron loss cone distribution can produce efficient scattering loss of plasma sheet electrons, which has a significant effect on the dynamics in the outer magnetosphere. Here we report two ECH emission events around the same location L≈ 5.7-5.8, MLT ≈ 12 from Van Allen Probes on 11 February (event A) and 9 January 2014 (event B), respectively. The spectrum of ECH waves was centered at the lower half of the harmonic bands during event A, but the upper half during event B. The observed electron phase space density in both events is fitted by the subtracted bi-Maxwellian distribution, and the fitting functions are used to evaluate the local growth rates of ECH waves based on a linear theory for homogeneous plasmas. ECH waves are excited by the loss cone instability of 50 eV-1 keV electrons in the lower half of harmonic bands in the low-density plasmasphere in event A, and 1-10 keV electrons in the upper half of harmonic bands in a relatively high-density region in event B. The current results successfully explain observations and provide a first direct evidence on how ECH waves are generated in the lower and upper half of harmonic frequency bands.

  2. Diffusive versus Displacive Contact Plasticity of Nanoscale Asperities: Temperature- and Velocity-Dependent Strongest Size.

    Science.gov (United States)

    Guo, Wei; Wang, Zhao; Li, Ju

    2015-10-14

    We predict a strongest size for the contact strength when asperity radii of curvature decrease below 10 nm. The reason for such strongest size is found to be correlated with the competition between the dislocation plasticity and surface diffusional plasticity. The essential role of temperature is calculated and illustrated in a comprehensive asperity size-strength-temperature map taking into account the effect of contact velocity. Such a map should be essential for various phenomena related to nanoscale contacts such as nanowire cold welding, self-assembly of nanoparticles and adhesive nanopillar arrays, as well as the electrical, thermal, and mechanical properties of macroscopic interfaces.

  3. The non-equilibrium response of a superconductor to pair-breaking radiation measured over a broad frequency band

    NARCIS (Netherlands)

    De Visser, P.J.; Yates, S.J.C.; Guruswamy, T.; Goldie, D.J.; Withington, S.; Neto, A.; Llombart, N.; Baryshev, A.M.; Klapwijk, T.M.; Baselmans, J.J.A.

    2015-01-01

    We have measured the absorption of terahertz radiation in a BCS superconductor over a broad range of frequencies from 200 GHz to 1.1 THz, using a broadband antenna-lens system and a tantalum microwave resonator. From low frequencies, the response of the resonator rises rapidly to a maximum at the

  4. The non-equilibrium response of a superconductor to pair-breaking radiation measured over a broad frequency band

    NARCIS (Netherlands)

    de Visser, P. J.; Yates, S. J. C.; Guruswamy, T.; Goldie, D. J.; Withington, S.; Neto, A.; Llombart, N.; Baryshev, A. M.; Klapwijk, T. M.; Baselmans, J. J. A.

    We have measured the absorption of terahertz radiation in a BCS superconductor over a broad range of frequencies from 200 GHz to 1.1 THz, using a broadband antenna-lens system and a tantalum microwave resonator. From low frequencies, the response of the resonator rises rapidly to a maximum at the

  5. Analysis and experimental evaluation of the frequency response of an indoor radiating cable in the UHF band

    OpenAIRE

    Seseña Osorio, Jorge A.; Zaldívar Huerta, Ignacio E.; Aragón Zavala, Alejandro; Castañón Ávila, Gerardo A.

    2015-01-01

    Abstract We present the modeling of the frequency response of the channel for a radiating cable system by using an autoregressive model for an indoor environment. The coefficients of the autoregressive model are determined from the experimental channel frequency response. Measurements were carried out in an indoor environment, in particular on the second floor of a university building in the frequency range of 1.3 to 1.8 GHz by using a vector network analyzer. It is demonstrated that the use ...

  6. Benchmarking CCMI models' top-of-atmosphere flux in the 9.6-µm ozone band using AURA TES Instantaneous Radiative Kernel

    Science.gov (United States)

    Kuai, L.; Bowman, K. W.; Worden, H. M.; Paulot, F.; Paynter, D.; Oman, L.; Strode, S. A.; Rozanov, E.; Stenke, A.; Revell, L. E.; Plummer, D. A.

    2017-12-01

    The estimated ozone radiative forcing (RF) from chemical-climate models range widely from +0.2 to +0.6 Wm-2. The reason has never been well understood. Since the ozone absorption in the 9.6 μm band contributes 97% of the O3 longwave RF, the variation of outgoing longwave radiation (OLR) due to ozone is dominant by this band. The observed TOA flux over 9.6 µm ozone band by Thermal Emission Spectrometer (TES) shows the global distribution has unique spatial patterns. In addition, the simulated TOA fluxes over 9.6 µm ozone band by different models have never been evaluated against observations. The bias of TOA flux from model could be primarily contributed by the bias of temperature, water vapor and ozone. Furthermore, the sensitivity of TOA flux to tropospheric ozone (instantaneous radiative kernel, IRK) may also affected by these biases (Kuai et al., 2017). The bias in TOA flux would eventually propagate into model calculations of ozone RF and cause divergence of the predictions of future climate by models. In this study, we applied the observation-based IRK product by AURA TES to attribute the CCMI model bias in TOA flux over 9.6 µm ozone band to ozone, water vapor, air temperature, and surface temperature. The comparisons of the three CCMI models (AM3, SOCOL3 and GEOCCM) to TES observations suggest that 1) all models underestimate the TOA flux at tropics and subtropics. 2) The TOA flux bias is comparable similar by AM3 and GEOSCC (-0.2 to -0.3 W/m2) however is larger for the relative young model, SOCOL3 (-0.4 to -0.6 W/m2). 3) The contributions by surface temperature are similarly moderate (-0.2 W/m2). 4) The contribution of ozone is largest by SOCOL3 (-0.3 W/m2), smallest by GEOSCCM (less than 0.1 W/m2) and moderate by AM3 (-0.2 W/m2). 5) Overall, the contributions by atmospheric temperature are all small (less than 0.1 W/m2). 6) The contribution of water vapor is negative and small by both SOCOL3 and GEOSCCM (0.1 W/m2) however large and positive by AM3 (0

  7. Polycyclic Aromatic Hydrocarbon Emission in Spitzer /IRS Maps. II. A Direct Link between Band Profiles and the Radiation Field Strength

    Energy Technology Data Exchange (ETDEWEB)

    Stock, D. J.; Peeters, E., E-mail: dstock84@gmail.com [Department of Physics and Astronomy, University of Western Ontario, London, ON, N6A 3K7 (Canada)

    2017-03-10

    We decompose the observed 7.7 μ m polycyclic aromatic hydrocarbon (PAH) emission complexes in a large sample of over 7000 mid-infrared spectra of the interstellar medium using spectral cubes observed with the Spitzer /IRS-SL instrument. In order to fit the 7.7 μ m PAH emission complex we invoke four Gaussian components, which are found to be very stable in terms of their peak positions and widths across all of our spectra, and subsequently define a decomposition with fixed parameters, which gives an acceptable fit for all the spectra. We see a strong environmental dependence on the interrelationships between our band fluxes—in the H ii regions all four components are intercorrelated, while in the reflection nebulae (RNs) the inner and outer pairs of bands correlate in the same manner as previously seen for NGC 2023. We show that this effect arises because the maps of RNs are dominated by emission from strongly irradiated photodissociation regions, while the much larger maps of H ii regions are dominated by emission from regions much more distant from the exciting stars, leading to subtly different spectral behavior. Further investigation of this dichotomy reveals that the ratio of two of these components (centered at 7.6 and 7.8 μ m) is linearly related to the UV-field intensity (log G {sub 0}). We find that this relationship does not hold for sources consisting of circumstellar material, which are known to have variable 7.7 μ m spectral profiles.

  8. Production of a narrow band of 0.511-MeV radiation by use of the PHERMEX bremsstrahlung spectrum

    International Nuclear Information System (INIS)

    Stroscio, M.A.

    1976-06-01

    The pair production cross section is numerically integrated over a typical PHERMEX bremsstrahlung spectrum to obtain the probability of pair production in a target of nuclear charge Z, and density rho. The pair production cross section used herein is only approximate in that it neglects screening, neglects the Coulomb field for the emerging pair (first Born approximation), and neglects pair production by atomic electrons. In spite of these approximations, an order-of-magnitude estimate of the amount of 0.511-MeV radiation produced by a typical pulse is still given

  9. Radiation

    International Nuclear Information System (INIS)

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  10. The non-equilibrium response of a superconductor to pair-breaking radiation measured over a broad frequency band

    Energy Technology Data Exchange (ETDEWEB)

    Visser, P. J. de, E-mail: p.j.devisser@tudelft.nl [Kavli Institute of NanoScience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Yates, S. J. C. [SRON Netherlands Institute for Space Research, Landleven 12, 9747AD Groningen (Netherlands); Guruswamy, T.; Goldie, D. J.; Withington, S. [Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Neto, A.; Llombart, N. [Faculty of Electrical Engineering, Mathematics and Computer Science, Terahertz Sensing Group, Delft University of Technology, Mekelweg 4, 2628 CD Delft (Netherlands); Baryshev, A. M. [SRON Netherlands Institute for Space Research, Landleven 12, 9747AD Groningen (Netherlands); Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen (Netherlands); Klapwijk, T. M. [Kavli Institute of NanoScience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Physics Department, Moscow State Pedagogical University, Moscow 119991 (Russian Federation); Baselmans, J. J. A. [SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht (Netherlands); Faculty of Electrical Engineering, Mathematics and Computer Science, Terahertz Sensing Group, Delft University of Technology, Mekelweg 4, 2628 CD Delft (Netherlands)

    2015-06-22

    We have measured the absorption of terahertz radiation in a BCS superconductor over a broad range of frequencies from 200 GHz to 1.1 THz, using a broadband antenna-lens system and a tantalum microwave resonator. From low frequencies, the response of the resonator rises rapidly to a maximum at the gap edge of the superconductor. From there on, the response drops to half the maximum response at twice the pair-breaking energy. At higher frequencies, the response rises again due to trapping of pair-breaking phonons in the superconductor. In practice, this is a measurement of the frequency dependence of the quasiparticle creation efficiency due to pair-breaking in a superconductor. The efficiency, calculated from the different non-equilibrium quasiparticle distribution functions at each frequency, is in agreement with the measurements.

  11. Quantification of trace elements in protein bands by synchrotron radiation x-ray fluorescence after isoelectric focusing separation of human hemoglobin

    International Nuclear Information System (INIS)

    Gao Yuxi; Chen Chunying; Li Bai; He Wei; Huang Yuying; Chai Zhifang

    2005-01-01

    The role and effects of a trace element in a particular organism strongly depend on its particular chemical forms in which the element is present. Therefore, the bulk content or concentration of an element in the organism of interest is often meaningless in judging its biological significance. To understand bioavailability, transportation, cell uptake, metabolism, toxicity, and other biological behaviors of trace elements in the body, information is needed about speciation of trace element, especially about distribution of metal-containing proteins. Development of appropriate methods for speciation analysis is therefore required. Synchrotron radiation x-ray fluorescence (SRXRF) is a sensitive method for multielemental analysis with detection limit of 10 ng/g. It has been successfully used for imaging and quantifying trace elements in various pathological and healthy tissues, even in a single cell, to help understand the mechanism of diseases and the biochemistry of elements. In our previous work, the technique was combined with electrophoresis to study distribution of metalloproteins in biological samples, but the quantitative analysis of trace elements in protein bands after electrophoresis was still unrealized. In this study, a procedure has been proposed for quantification of Fe, Cu, and Zn in protein bands with SRXRF analysis after isoelectric focusing (IEF) separation. Calibration standards were prepared by adding certain amounts of metal ions and free-metal proteins to electrophoresis gel. Human hemoglobin was separated with IEF, and Fe, Cu, and Zn in protein bands were analyzed by SRXRF. The calibration curves can be obtained in a range of 0-8 mg/kg metals and a linear relationship between dosage of metals and fluorescent intensity can be observed (r 2 > 0.99). The method provides the detection limits of 2.43, 1.12, and 0.96 mg/kg for Fe, Cu and Zn, and the recoveries of 90.4 and 115.7 % for Fe and Zn, respectively. The hyphenated technique of SRXRF and IEF

  12. Caregiver burden: the strongest predictor of self-rated health in caregivers of patients with dementia.

    Science.gov (United States)

    Abdollahpour, Ibrahim; Nedjat, Saharnaz; Noroozian, Maryam; Salimi, Yahya; Majdzadeh, Reza

    2014-09-01

    People having dementia need help and supervision to perform their activities of daily living. This responsibility is usually imposed on family members who endure a great burden, leading to undesirable health outcomes. The aims of our study were to measure caregivers' health as well as identify its adjusted relevant predictors. One hundred and fifty three registered patients and their caregivers from Iranian Alzheimer Association were included in this cross-sectional study through sequential sampling. Self-rated health (SRH) was measured using a single question with Likert-type scale ranging from very bad (1) to very good (5). The multiple linear regression model was applied to determine the adjusted associations between independent variables under study and SRH. The mean caregiver SRH level was 3.03. Of the participant caregivers, 29% were either unsatisfied or very unsatisfied with their health level. In the final regression model, SRH showed a direct significant association with the patient's number of children but an inverse significant association with the marital status (married patients), patient's age, and caregiver burden. Caregiver burden was not only significantly associated with poor SRH after removing the effect of the other covariates but it was also recognized as the strongest predictor of caregivers' SRH. Therefore, it seems that development of intervention programs, in order to reduce caregiver burden, can be considered as important step in promoting caregivers' health level. © The Author(s) 2014.

  13. ON POTENTIAL REPRESENTATIONS OF THE DISTRIBUTION LAW OF RARE STRONGEST EARTHQUAKES

    Directory of Open Access Journals (Sweden)

    M. V. Rodkin

    2014-01-01

    Full Text Available Assessment of long-term seismic hazard is critically dependent on the behavior of tail of the distribution function of rare strongest earthquakes. Analyses of empirical data cannot however yield the credible solution of this problem because the instrumental catalogs of earthquake are available only for a rather short time intervals, and the uncertainty in estimations of magnitude of paleoearthquakes is high. From the available data, it was possible only to propose a number of alternative models characterizing the distribution of rare strongest earthquakes. There are the following models: the model based on theGuttenberg – Richter law suggested to be valid until a maximum possible seismic event (Мmах, models of 'bend down' of earthquake recurrence curve, and the characteristic earthquakes model. We discuss these models from the general physical concepts supported by the theory of extreme values (with reference to the generalized extreme value (GEV distribution and the generalized Pareto distribution (GPD and the multiplicative cascade model of seismic regime. In terms of the multiplicative cascade model, seismic regime is treated as a large number of episodes of avalanche-type relaxation of metastable states which take place in a set of metastable sub-systems.The model of magnitude-unlimited continuation of the Guttenberg – Richter law is invalid from the physical point of view because it corresponds to an infinite mean value of seismic energy and infinite capacity of the process generating seismicity. A model of an abrupt cut of this law by a maximum possible event, Мmах is not fully logical either.A model with the 'bend-down' of earthquake recurrence curve can ensure both continuity of the distribution law and finiteness of seismic energy value. Results of studies with the use of the theory of extreme values provide a convincing support to the model of 'bend-down' of earthquakes’ recurrence curve. Moreover they testify also that the

  14. Annona muricata leaves have strongest cytotoxic activity against breast cancer cells

    Directory of Open Access Journals (Sweden)

    Susi Endrini

    2014-12-01

    Full Text Available Background Plant-derived herbal compounds have a long history of clinical use, better patient tolerance and acceptance. They are freely available natural compounds that can be safely used to prevent various ailments. Plants have been the basis of traditional medicine throughout the world for thousands of years and are providing mankind with new remedies. The objective of this study was to determine the cytotoxicity of soursop (Anona muricata Linn leaves and pearl grass (Hedyotis corymbosa (L. Lam. on the hormone-dependent human breast carcinoma Michigan Cancer Foundation-7 (MCF-7 cell line. Methods This study used two types of solvents (water and ethanol in the extraction process and two incubation times (24 hours and 48 hours in the MTT assays to analyze the cytotoxic effects of both plants. Results Preliminary results showed that the ethanolic extract of soursop leaves (SE displayed cytotoxic effects against MCF-7 on 24- and 48-hour incubation times with IC50 values of 88.788 ìg/ml and 14.678 mg/ml, respectively. Ethanolic pearl grass extract (PE showed similar results, with IC50 values of 65.011 mg/ml on 24-hour incubation time and 52.329 mg/ml on 48-hour incubation time against MCF-7 cell line. However, the water extract of both plants displayed lower cytotoxic effect against MCF-7 cell line. Conclusion The ethanolic extract of both plants displayed cytotoxic effect against MCF-7. Soursop (Anona muricata Linn leaves have the strongest cytotoxic activity against MCF-7 breast cancer cell line.

  15. Annona muricata leaves have strongest cytotoxic activity against breast cancer cells

    Directory of Open Access Journals (Sweden)

    Susi Endrini

    2015-12-01

    Full Text Available BACKGROUND Plant-derived herbal compounds have a long history of clinical use, better patient tolerance and acceptance. They are freely available natural compounds that can be safely used to prevent various ailments. Plants have been the basis of traditional medicine throughout the world for thousands of years and are providing mankind with new remedies. The objective of this study was to determine the cytotoxicity of soursop (Anona muricata Linn leaves and pearl grass (Hedyotis corymbosa (L. Lam. on the hormone-dependent human breast carcinoma Michigan Cancer Foundation-7 (MCF-7 cell line. METHODS This study used two types of solvents (water and ethanol in the extraction process and two incubation times (24 hours and 48 hours in the MTT assays to analyze the cytotoxic effects of both plants. RESULTS Preliminary results showed that the ethanolic extract of soursop leaves (SE displayed cytotoxic effects against MCF-7 on 24- and 48-hour incubation times with IC50 values of 88.788 μg/ml and 14.678 μg/ml, respectively. Ethanolic pearl grass extract (PE showed similar results, with IC50 values of 65.011 μg/ ml on 24-hour incubation time and 52.329 μg/ml on 48-hour incubation time against MCF-7 cell line. However, the water extract of both plants displayed lower cytotoxic effect against MCF-7 cell line. CONCLUSION The ethanolic extract of both plants displayed cytotoxic effect against MCF-7. Soursop (Anona muricata Linn leaves have the strongest cytotoxic activity against MCF-7 breast cancer cell line.

  16. Timed Stair Climbing is the Single Strongest Predictor of Perioperative Complications in Patients Undergoing Abdominal Surgery

    Science.gov (United States)

    Reddy, Sushanth; Contreras, Carlo M; Singletary, Brandon; Bradford, T Miller; Waldrop, Mary G; Mims, Andrew H; Smedley, W Andrew; Swords, Jacob A; Thomas N, Wang; Martin J, Heslin

    2016-01-01

    Background Current methods to predict patients' peri-operative morbidity utilize complex algorithms with multiple clinical variables focusing primarily on organ-specific compromise. The aim of the present study is to determine the value of a timed stair climb (SC) in predicting peri-operative complications for patients undergoing abdominal surgery. Study Design From March 2014 to July 2015, 362 patients attempted SC while being timed prior to undergoing elective abdominal surgery. Vital signs were measured before and after SC. Ninety day post-operative complications were assessed by the Accordion Severity Grading System. The prognostic value of SC was compared to the ACS NSQIP risk calculator. Results A total of 264 (97.4%) patients were able to complete SC. SC time directly correlated to changes in both mean arterial pressure and heart rate as an indicator of stress. An Accordion grade 2 or higher complication occurred in 84 (25%) patients. There were 8 mortalities (2.4%). Patients with slower SC times had an increased complication rate (P<0.0001). In multivariable analysis SC time was the single strongest predictor of complications (OR=1.029, P<0.0001), and no other clinical co-morbidity reached statistical significance. Receiver operative characteristic curves predicting post-operative morbidity by SC time was superior to that of the ACS risk calculator (AUC 0.81 vs. 0.62, P<0.0001). Additionally slower patients had a greater deviation from predicted length of hospital stay (P=0.034) Conclusions SC provides measurable stress, accurately predicts post-operative complications, and is easy to administer in patients undergoing abdominal surgery. Larger patient populations with a diverse group of operations will be needed to further validate the use of SC in risk prediction models. PMID:26920993

  17. Education is the strongest socio-economic predictor of smoking in pregnancy.

    Science.gov (United States)

    Härkönen, Juho; Lindberg, Matti; Karlsson, Linnea; Karlsson, Hasse; Scheinin, Noora M

    2018-01-14

    To investigate socio-economic disparities in smoking in pregnancy (SIP) by the mother's education, occupational class and current economic conditions. Cross-sectional analysis with linked survey and register data. South-western Finland. A total of 2667 pregnant women [70% of the original sample (n = 3808)] from FinnBrain, a prospective pregnancy cohort study. The outcome was smoking during the first pregnancy trimester, measured from the Finnish Medical Birth Register. Education and occupational class were linked from population registers. Income support recipiency and subjective economic wellbeing were questionnaire-based measures of current economic conditions. These were adjusted for age, partnership status, residential area type, parental separation, parity, childhood socio-economic background, childhood adversities (the Trauma and Distressing Events During Childhood scale) and antenatal stress (Edinburgh Postnatal Depression Scale). Logistic regressions and attributable fractions (AF) were estimated. Mother's education was the strongest socio-economic predictor of SIP. Compared with university education, adjusted odds ratios (aORs) of SIP were: 2.2 [95% confidence interval (CI) = 1.2-3.9; P = 0.011] for tertiary vocational education, 4.4 (95% CI = 2.1-9.0; P education, 2.9 (95% CI = 1.4-6.1; P = 0.006) for general secondary education, 9.5 (95% CI 5.0-18.2; P education and 14.4 (95% CI = 6.3-33.0; P education was 0.5. Adjusted for the other variables, occupational class and subjective economic wellbeing did not predict SIP. Income support recipiency was associated positively with SIP (aOR = 1.8; 95% CI = 1.1-3.1; P = 0.022). Antenatal stress predicted SIP (aOR = 2.0; 95% CI = 1.4-2.8; P pregnancy are attributable primarily to differences in the mother's educational level (low versus high) and orientation (vocational versus general). © 2018 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study

  18. Radiation

    International Nuclear Information System (INIS)

    Davidson, J.H.

    1986-01-01

    The basic facts about radiation are explained, along with some simple and natural ways of combating its ill-effects, based on ancient healing wisdom as well as the latest biochemical and technological research. Details are also given of the diet that saved thousands of lives in Nagasaki after the Atomic bomb attack. Special comment is made on the use of radiation for food processing. (U.K.)

  19. AP diameter shows the strongest correlation with CTDI and DLP in abdominal and chest CT.

    LENUS (Irish Health Repository)

    Zarb, Francis

    2010-01-01

    The purpose of this study is to investigate the relationships among cross-sectional diameters, weight and computed tomography (CT) dose descriptors (CTDI and DLP) to identify which is best used as a measure for the establishment of DRLs in CT. Data (gender, weight, cross-sectional diameters, dose descriptors) from 56 adult patients attending for either a CT examination of the abdomen or chest was obtained from two spiral CT units using automatic milliampere modulation. The AP diameter was demonstrated as the main contributing factor influencing the dose in CT (CTDI: r(2) = 0.269, p-value < or =0.001; DLP: r(2) = 0.260, p-value < or =0.001) since it has a greater correlation with radiation dose than body weight and can thus be its substitute in dose-reduction strategies and establishment of DRLs. The advantages of using the AP diameter are that it can easily be measured prior to scanning or retrospectively from previous CT images. However, further studies on the practicality of this approach are recommended.

  20. AP diameter shows the strongest correlation with CTDI and DLP in abdominal and chest CT

    International Nuclear Information System (INIS)

    Zarb, F.; Rainford, L.; McEntee, M. F.

    2010-01-01

    The purpose of this study is to investigate the relationships among cross-sectional diameters, weight and computed tomography (CT) dose descriptors (CTDI and DLP) to identify which is best used as a measure for the establishment of DRLs in CT. Data (gender, weight, cross-sectional diameters, dose descriptors) from 56 adult patients attending for either a CT examination of the abdomen or chest was obtained from two spiral CT units using automatic milli-ampere modulation. The AP diameter was demonstrated as the main contributing factor influencing the dose in CT (CTDI: r 2 = 0.269, p-value ≤0.001; DLP: r 2 = 0.260, p-value ≤0.001) since it has a greater correlation with radiation dose than body weight and can thus be its substitute in dose-reduction strategies and establishment of DRLs. The advantages of using the AP diameter are that it can easily be measured prior to scanning or retrospectively from previous CT images. However, further studies on the practicality of this approach are recommended. (authors)

  1. Production of a narrow band of 0. 511-MeV radiation by use of the PHERMEX bremsstrahlung spectrum. [Cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Stroscio, M.A.

    1976-06-01

    The pair production cross section is numerically integrated over a typical PHERMEX bremsstrahlung spectrum to obtain the probability of pair production in a target of nuclear charge Z, and density rho. The pair production cross section used herein is only approximate in that it neglects screening, neglects the Coulomb field for the emerging pair (first Born approximation), and neglects pair production by atomic electrons. In spite of these approximations, an order-of-magnitude estimate of the amount of 0.511-MeV radiation produced by a typical pulse is still given.

  2. Levothyroxine therapy and impaired clearance are the strongest contributors to small intestinal bacterial overgrowth: Results of a retrospective cohort study.

    Science.gov (United States)

    Brechmann, Thorsten; Sperlbaum, Andre; Schmiegel, Wolff

    2017-02-07

    To identify a set of contributors, and weight and rank them on a pathophysiological basis. Patients who have undergone a lactulose or glucose hydrogen breath test to rule out small intestinal bacterial overgrowth (SIBO) for various clinical symptoms, including diarrhoea, weight loss, abdominal pain, cramping or bloating, were seen as eligible for inclusion in a retrospective single-centre study. Clinical data such as co-morbidities, medication, laboratory parameters and other possible risk factors have been identified from the electronic data system. Cases lacking or with substantially incomplete clinical data were excluded from the analysis. Suspected contributors were summarised under four different pathophysiological pathways (impaired gastric acid barrier, impaired intestinal clearance, immunosuppression and miscellaneous factors including thyroid gland variables) and investigated using the χ 2 test, Student's t -test and logistic regression models. A total of 1809 patients who had undergone hydrogen breath testing were analysed. Impairment of the gastric acid barrier (gastrectomy, odds ratio: OR = 3.5, PPI therapy OR = 1.4), impairment of intestinal clearance (any resecting gastric surgery OR = 2.6, any colonic resection OR = 1.9, stenosis OR = 3.4, gastroparesis OR = 3.4, neuropathy 2.2), immunological factors (any drug-induced immunosuppression OR = 1.8), altered thyroid gland metabolism (hypothyroidism OR = 2.6, levothyroxine therapy OR = 3.0) and diabetes mellitus (OR = 1.9) were associated significantly to SIBO. Any abdominal surgery, ileocecal resection, vagotomy or IgA-deficiency did not have any influence, and a history of appendectomy decreased the risk of SIBO. Multivariate analysis revealed gastric surgery, stenoses, medical immunosuppression and levothyroxine to be the strongest predictors. Levothyroxine therapy was the strongest contributor in a simplified model (OR = 3.0). The most important contributors for the development of SIBO in ascending

  3. HYBASE : HYperspectral BAnd SElection

    NARCIS (Netherlands)

    Schwering, P.B.W.; Bekman, H.H.P.T.; Seijen, H.H. van

    2009-01-01

    Band selection is essential in the design of multispectral sensor systems. This paper describes the TNO hyperspectral band selection tool HYBASE. It calculates the optimum band positions given the number of bands and the width of the spectral bands. HYBASE is used to assess the minimum number of

  4. Microwave-Assisted Synthesis of Boron and Nitrogen co-doped Reduced Graphene Oxide for the Protection of Electromagnetic Radiation in Ku-Band.

    Science.gov (United States)

    Umrao, Sima; Gupta, Tejendra K; Kumar, Shiv; Singh, Vijay K; Sultania, Manish K; Jung, Jung Hwan; Oh, Il-Kwon; Srivastava, Anchal

    2015-09-09

    The electromagnetic interference (EMI) shielding of reduced graphene oxide (MRG), B-doped MRG (B-MRG), N-doped MRG (N-MRG), and B-N co-doped MRG (B-N-MRG) have been studied in the Ku-band frequency range (12.8-18 GHz). We have developed a green, fast, and cost-effective microwave assisted route for synthesis of doped MRG. B-N-MRG shows high electrical conductivity in comparison to MRG, B-MRG and N-MRG, which results better electromagnetic interference (EMI) shielding ability. The co-doping of B and N significantly enhances the electrical conductivity of MRG from 21.4 to 124.4 Sm(-1) because N introduces electrons and B provides holes in the system and may form a nanojunction inside the material. Their temperature-dependent electrical conductivity follows 2D-variable range hopping (2D-VRH) and Efros-Shklovskii-VRH (ES-VRH) conduction model in a low temperature range (T<50 K). The spatial configuration of MRG after doping of B and N enhances the space charge polarization, natural resonance, dielectric polarization, and trapping of EM waves by internal reflection leading to a high EMI shielding of -42 dB (∼99.99% attenuation) compared to undoped MRG (-28 dB) at a critical thickness of 1.2 mm. Results suggest that the B-N-MRG has great potential as a candidate for a new type of EMI shielding material useful in aircraft, defense industries, communication systems, and stealth technology.

  5. Do nonphysical punishments reduce antisocial behavior more than spanking? a comparison using the strongest previous causal evidence against spanking

    Directory of Open Access Journals (Sweden)

    Cox Ronald B

    2010-02-01

    Full Text Available Abstract Background The strongest causal evidence that customary spanking increases antisocial behavior is based on prospective studies that control statistically for initial antisocial differences. None of those studies have investigated alternative disciplinary tactics that parents could use instead of spanking, however. Further, the small effects in those studies could be artifactual due to residual confounding, reflecting child effects on the frequency of all disciplinary tactics. This study re-analyzes the strongest causal evidence against customary spanking and uses these same methods to determine whether alternative disciplinary tactics are more effective in reducing antisocial behavior. Methods This study re-analyzed a study by Straus et al.1 on spanking and antisocial behavior using a sample of 785 children who were 6 to 9 years old in the 1988 cohort of the American National Longitudinal Survey of Youth. The comprehensiveness and reliability of the covariate measure of initial antisocial behavior were varied to test for residual confounding. All analyses were repeated for grounding, privilege removal, and sending children to their room, and for psychotherapy. To account for covarying use of disciplinary tactics, the analyses were redone first for the 73% who had reported using at least one discipline tactic and second by controlling for usage of other disciplinary tactics and psychotherapy. Results The apparently adverse effect of spanking on antisocial behavior was replicated using the original trichotomous covariate for initial antisocial behavior. A similar pattern of adverse effects was shown for grounding and psychotherapy and partially for the other two disciplinary tactics. All of these effects became non-significant after controlling for latent comprehensive measures of externalizing behavior problems. Conclusions These results are consistent with residual confounding, a statistical artifact that makes all corrective actions by

  6. Perception and the strongest sensory memory trace of multi-stable displays both form shortly after the stimulus onset.

    Science.gov (United States)

    Pastukhov, Alexander

    2016-02-01

    We investigated the relation between perception and sensory memory of multi-stable structure-from-motion displays. The latter is an implicit visual memory that reflects a recent history of perceptual dominance and influences only the initial perception of multi-stable displays. First, we established the earliest time point when the direction of an illusory rotation can be reversed after the display onset (29-114 ms). Because our display manipulation did not bias perception towards a specific direction of illusory rotation but only signaled the change in motion, this means that the perceptual dominance was established no later than 29-114 ms after the stimulus onset. Second, we used orientation-selectivity of sensory memory to establish which display orientation produced the strongest memory trace and when this orientation was presented during the preceding prime interval (80-140 ms). Surprisingly, both estimates point towards the time interval immediately after the display onset, indicating that both perception and sensory memory form at approximately the same time. This suggests a tighter integration between perception and sensory memory than previously thought, warrants a reconsideration of its role in visual perception, and indicates that sensory memory could be a unique behavioral correlate of the earlier perceptual inference that can be studied post hoc.

  7. The dynamics of competitive activity performance of the strongest athletes in the world during the Olympic year

    Directory of Open Access Journals (Sweden)

    Rabin Muhammad Fahmi

    2016-12-01

    Full Text Available The paper scrutinizes the annual dynamics of competitive activity performance of prize winners in track and field of the Games of the XXXI Olympiad in Rio de Janeiro. The studies performed allow to identify two basic strategies of participation of elite athletes in the competitions. The first implies a strong focus on achieving the best results in major competitions of the year. It is used by most of the strongest athletes in the world. The second focuses the athlete on the effective combination of competitive activity in major competitions of the year (the Olympics and World Championships and in the Diamond League. As shown by the experience of the best sports practice, only a limited number of athletes manage to implement the latter strategy. The methodological approaches to planning competitive activity during the year are identified. The first involves the rational allocation of the optimal number of competitions throughout the year, the second focuses on preparatory competitive activities of a fairly high intensity, and the third involves the use of a small number of competitions in the system of annual training.

  8. The 100 strongest radio point sources in the field of the Large Magellanic Cloud at 1.4 GHz

    Directory of Open Access Journals (Sweden)

    Payne J.L.

    2009-01-01

    Full Text Available We present the 100 strongest 1.4 GHz point sources from a new mosaic image in the direction of the Large Magellanic Cloud (LMC. The observations making up the mosaic were made using Australia Telescope Compact Array (ATCA over a ten year period and were combined with Parkes single dish data at 1.4 GHz to complete the image for short spacing. An initial list of co-identifications within 1000 at 0.843, 4.8 and 8.6 GHz consisted of 2682 sources. Elimination of extended objects and artifact noise allowed the creation of a refined list containing 1988 point sources. Most of these are presumed to be background objects seen through the LMC; a small portion may represent compact H ii regions, young SNRs and radio planetary nebulae. For the 1988 point sources we find a preliminary average spectral index (α of -0.53 and present a 1.4 GHz image showing source location in the direction of the LMC.

  9. The 100 Strongest Radio Point Sources in the Field of the Large Magellanic Cloud at 1.4 GHz

    Directory of Open Access Journals (Sweden)

    Payne, J. L.

    2009-06-01

    Full Text Available We present the 100 strongest 1.4~GHz point sources from a new mosaicimage in the direction of the Large Magellanic Cloud (LMC. The observationsmaking up the mosaic were made using Australia Telescope Compact Array (ATCAover a ten year period and were combined with Parkes single dish data at 1.4 GHz to complete the image for short spacing. An initial list of co-identifications within 10arcsec at 0.843, 4.8 and 8.6 GHz consisted of 2682 sources. Elimination of extended objects and artifact noise allowed the creation of a refined list containing 1988 point sources. Most of these are presumed to be background objects seen through the LMC; a small portion may represent compact HII regions, young SNRs and radio planetary nebulae. For the 1988 point sources we find a preliminary average spectral index ($alpha$ of -0.53 and present a 1.4 GHz image showing source locationin the direction of the LMC.

  10. Muscle quality and relative adiposity are the strongest predictors of lower-extremity physical function in older women.

    Science.gov (United States)

    Straight, Chad R; Brady, Anne O; Evans, Ellen M

    2015-01-01

    The aim of this study was to examine the relative contributions of physical activity, adiposity, lean mass and muscle quality to lower-extremity physical function (LEPF) in older women. Cross-sectional analysis at a university research laboratory. Community-dwelling older women (n=96, 73.9 ± 5.6 years, BMI=26.5 ± 4.7 kg/m(2)) were assessed for body composition via dual-energy X-ray absorptiometry, leg extension power using the Nottingham power rig, muscle quality (W/kg) as the ratio of leg extension power (W) to lower-body mineral free lean mass (kg) and moderate-intensity physical activity via questionnaire. A composite measure of LEPF was calculated by summing Z-scores of the 6-min walk, 8-foot up-and-go and 30-s chair stand tests. Muscle quality and physical activity were associated with all measures of LEPF (all p0.05). Hierarchical linear regression analyses revealed that muscle quality (standardized β=0.47, pquality and relative adiposity are the strongest independent predictors of LEPF in older women. These findings suggest that maintaining muscle quality, especially relative to adiposity, may be a critical target for interventions to prevent declines in physical function in older women. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. Evidence for the strongest version of the 4d a-theorem via a-maximization along RG flows

    International Nuclear Information System (INIS)

    Barnes, Edwin; Intriligator, Ken; Wecht, Brian; Wright, Jason

    2004-01-01

    In earlier work, we (KI and BW) gave a two line 'almost proof' (for supersymmetric RG flows) of the weakest form of the conjectured 4d a-theorem, that aIRaUV, using our result that the exact superconformal R-symmetry of 4d SCFTs maximizes a=3TrR3-TrR. The proof was incomplete because of two identified loopholes: theories with accidental symmetries, and the fact that it is only a local maximum of a. Here we discuss and extend a proposal of Kutasov (which helps close the latter loophole) in which a-maximization is generalized away from the endpoints of the RG flow, with Lagrange multipliers that are conjectured to be identified with the running coupling constants. a-maximization then yields a monotonically decreasing 'a-function' along the RG flow to the IR. As we discuss, this proposal in fact suggests the strongest version of the a-theorem: that 4d RG flows are gradient flows of an a-function, with positive-definite metric. In the perturbative limit, the RG flow metric thus obtained is shown to agree precisely with that found by very different computations by Osborn and collaborators. As examples, we discuss a new class of 4d SCFTs, along with their dual descriptions and IR phases, obtained from SQCD by coupling some of the flavors to added singlets

  12. S-band active array filtenna with enhanced X-band spurious interference suppression

    NARCIS (Netherlands)

    Cifola, L.; Gerini, G.; Berg, S. van den; Water, F. van de

    2014-01-01

    In the present work, the design of an S-band active array antenna with inherent frequency selectivity properties is described. The radiating element, based on a stacked-patch configuration, is characterized by an operational bandwidth of [2.8-3.4] GHz. In-band frequency selectivity is performed by a

  13. L-band brightness temperature disaggregation for use with S-band and C-band radiometer data for WCOM

    Science.gov (United States)

    Yao, P.; Shi, J.; Zhao, T.; Cosh, M. H.; Bindlish, R.

    2017-12-01

    There are two passive microwave sensors onboard the Water Cycle Observation Mission (WCOM), which includes a synthetic aperture radiometer operating at L-S-C bands and a scanning microwave radiometer operating from C- to W-bands. It provides a unique opportunity to disaggregate L-band brightness temperature (soil moisture) with S-band C-bands radiometer data. In this study, passive-only downscaling methodologies are developed and evaluated. Based on the radiative transfer modeling, it was found that the TBs (brightness temperature) between the L-band and S-band exhibit a linear relationship, and there is an exponential relationship between L-band and C-band. We carried out the downscaling results by two methods: (1) downscaling with L-S-C band passive measurements with the same incidence angle from payload IMI; (2) downscaling with L-C band passive measurements with different incidence angle from payloads IMI and PMI. The downscaling method with L-S bands with the same incident angle was first evaluated using SMEX02 data. The RMSE are 2.69 K and 1.52 K for H and V polarization respectively. The downscaling method with L-C bands is developed with different incident angles using SMEX03 data. The RMSE are 2.97 K and 2.68 K for H and V polarization respectively. These results showed that high-resolution L-band brightness temperature and soil moisture products could be generated from the future WCOM passive-only observations.

  14. The Strongest Acceleration of >40 keV Electrons by ICME-driven Shocks at 1 au

    Science.gov (United States)

    Yang, Liu; Wang, Linghua; Li, Gang; Wimmer-Schweingruber, Robert F.; He, Jiansen; Tu, Chuanyi; Tian, Hui; Bale, Stuart D.

    2018-01-01

    We present two case studies of the in-situ electron acceleration during the 2000 February 11 shock and the 2004 July 22 shock, with the strongest electron flux enhancement at 40 keV across the shock, among all the quasi-perpendicular and quasi-parallel ICME-driven shocks observed by the WIND 3DP instrument from 1995 through 2014 at 1 au. We find that for this quasi-perpendicular (quasi-parallel) shock on 2000 February 11 (2004 July 22), the shocked electron differential fluxes at ∼0.4–50 keV in the downstream generally fit well to a double-power-law spectrum, J ∼ E ‑β , with an index of β ∼ 3.15 (4.0) at energies below a break at ∼3 keV (∼1 keV) and β ∼ 2.65 (2.6) at energies above. For both shock events, the downstream electron spectral indices appear to be similar for all pitch angles, which are significantly larger than the index prediction by diffusive shock acceleration. In addition, the downstream electron pitch-angle distributions show the anisotropic beams in the anti-sunward-traveling direction, while the ratio of the downstream over ambient fluxes appears to peak near 90° pitch angles, at all energies of ∼0.4–50 keV. These results suggest that in both shocks, shock drift acceleration likely plays an important role in accelerating electrons in situ at 1 au. Such ICME-driven shocks could contribute to the formation of solar wind halo electrons at energies ≲2 keV, as well as the production of solar wind superhalo electrons at energies ≳2 keV in interplanetary space.

  15. Constraining the physical conditions in the jets of γ-ray flaring blazars using centimeter-band polarimetry and radiative transfer simulations. I. Data and models for 0420–014, OJ 287, and 1156+295

    Energy Technology Data Exchange (ETDEWEB)

    Aller, M. F.; Hughes, P. A.; Aller, H. D.; Latimer, G. E. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109-1042 (United States); Hovatta, T., E-mail: mfa@umich.edu [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States)

    2014-08-10

    To investigate parsec-scale jet flow conditions during GeV γ-ray flares detected by the Fermi Large Angle Telescope, we obtained centimeter-band total flux density and linear polarization monitoring observations from 2009.5 through 2012.5 with the 26 m Michigan radio telescope for a sample of core-dominated blazars. We use these data to constrain radiative transfer simulations incorporating propagating shocks oriented at an arbitrary angle to the flow direction in order to set limits on the jet flow and shock parameters during flares temporally associated with γ-ray flares in 0420–014, OJ 287, and 1156+295; these active galactic nuclei exhibited the expected signature of shocks in the linear polarization data. Both the number of shocks comprising an individual radio outburst (3 and 4) and the range of the compression ratios of the individual shocks (0.5-0.8) are similar in all three sources; the shocks are found to be forward-moving with respect to the flow. While simulations incorporating transverse shocks provide good fits for 0420–014 and 1156+295, oblique shocks are required for modeling the OJ 287 outburst, and an unusually low value of the low-energy cutoff of the radiating particles' energy distribution is also identified. Our derived viewing angles and shock speeds are consistent with independent Very Long Baseline Array results. While a random component dominates the jet magnetic field, as evidenced by the low fractional linear polarization, to reproduce the observed spectral character requires that a significant fraction of the magnetic field energy is in an ordered axial component. Both straight and low pitch angle helical field lines are viable scenarios.

  16. Hemoglobin to Hematocrit Ratio: The Strongest Predictor of Femoral Head Osteonecrosis in Children With Sickle Cell Disease.

    Science.gov (United States)

    Worrall, Douglas; Smith-Whitley, Kim; Wells, Lawrence

    2016-03-01

    Femoral head osteonecrosis (ON) secondary to sickle cell disease (SCD) often progresses to femoral head collapse, requiring total hip arthroplasty. However, this treatment has a limited durability and patients with SCD have higher rates of complications, requiring multiple revision operations. Identifying risk factors linked to ON in SCD can facilitate earlier precollapse diagnosis and surgical treatment aimed at preservation of the native hip joint. Fifty-nine children treated at our institution between January 2001 and April 2012 with SCD and ON, as diagnosed by magnetic resonance imaging or radiographic imaging, were compared with age-matched and sickle cell phenotype-matched (SS, SC, Sβ, Sβ) controls with no evidence of ON. Two sided t-tests assuming unequal variances determined statistically risk factors and threshold values were assigned to calculate odds ratios. Systolic blood pressure (P=1.2×10, OR=3.68), diastolic blood pressure (P=0.0084, OR=1.41), weight in the SCD-SS population (P=0.04, OR=1.85), and hemoglobin (Hb) in the SCD-SS population (P=0.036, OR=2.56) were elevated in cases. Curiously, dividing the Hb by the hematocrit to serve as a clinical proxy for the mean corpuscular Hb concentration (MCHC) produced an excellent predictor of ON (P=2.06×10, OR=5.17), which was especially pronounced in the SCD-SS subpopulation (P=2.28×10, OR=8.65). Among children with SCD, the overall prevalence of ON was 9% (59/658) and the phenotype with the highest prevalence of ON was Sβ thalassemia with an ON prevalence of 11.1%. There was no observed correlation between ON and height, body mass index, cholesterol, mean corpuscular volume, hematocrit, or glucocorticoid use. These data support a novel clinical marker, the MCHC proxy, as the strongest predictor of ON in children with SCD. High-risk children should receive hip magnetic resonance imaging to diagnose early ON and facilitate interventions focused on hip preservation, forestalling, or possibly preventing

  17. Band structure of semiconductors

    CERN Document Server

    Tsidilkovski, I M

    2013-01-01

    Band Structure of Semiconductors provides a review of the theoretical and experimental methods of investigating band structure and an analysis of the results of the developments in this field. The book presents the problems, methods, and applications in the study of band structure. Topics on the computational methods of band structure; band structures of important semiconducting materials; behavior of an electron in a perturbed periodic field; effective masses and g-factors for the most commonly encountered band structures; and the treatment of cyclotron resonance, Shubnikov-de Haas oscillatio

  18. Universal EUV in-band intensity detector

    Science.gov (United States)

    Berger, Kurt W.

    2004-08-24

    Extreme ultraviolet light is detected using a universal in-band detector for detecting extreme ultraviolet radiation that includes: (a) an EUV sensitive photodiode having a diode active area that generates a current responsive to EUV radiation; (b) one or more mirrors that reflects EUV radiation having a defined wavelength(s) to the diode active area; and (c) a mask defining a pinhole that is positioned above the diode active area, wherein EUV radiation passing through the pinhole is restricted substantially to illuminating the diode active area.

  19. Irradiation-induced degradation of PTB7 investigated by valence band and S 2p photoelectron spectroscopy

    Science.gov (United States)

    Darlatt, Erik; Muhsin, Burhan; Roesch, Roland; Lupulescu, Cosmin; Roth, Friedrich; Kolbe, Michael; Gottwald, Alexander; Hoppe, Harald; Richter, Mathias

    2016-08-01

    Monochromatic radiation with known absolute radiant power from an undulator at the electron storage ring Metrology Light Source (MLS) was used to irradiate PTB7 (a thieno[3, 4-b]thiophene-alt-benzodithiophene polymer) thin films at wavelengths (photon energies) of 185 nm (6.70 eV), 220 nm (5.64 eV), 300 nm (4.13 eV), 320 nm (3.88 eV), 356 nm (3.48 eV) and 675 nm (1.84 eV) under ultra-high vacuum conditions for the investigation of radiation-induced degradation effects. The characterization of the thin films is focused at ultraviolet photoelectron spectroscopy (UPS) of valence bands and is complemented by S 2p x-ray photoelectron spectroscopy (S 2p XPS) before and after the irradiation procedure. The radiant exposure was determined for each irradiation by means of photodiodes traceably calibrated to the international system of units SI. The valence band spectra show the strongest changes for the shortest wavelengths and no degradation effect at 356 nm and 675 nm even with the highest radiant exposure applied. In the spectral range where the Sun appears bright on the Earth’s surface, no degradation effects are observed.

  20. Heart and/or soul : reality and fiction in the association between the two strongest contributors to the global burden of disease - ischemic heart disease and depression

    NARCIS (Netherlands)

    de Jonge, Peter

    Depression and heart disease are the strongest contributors to the global burden of disease and are often intertwined: depression is a risk factor for heart disease and vice versa. Moreover, depression in patients with established heart disease is associated with cardiovascular disease progression.

  1. Wide Band to ''Double Band'' upgrade

    International Nuclear Information System (INIS)

    Kasper, P.; Currier, R.; Garbincius, P.; Butler, J.

    1988-06-01

    The Wide Band beam currently uses electrons obtained from secondary photon conversions to produce the photon beam incident on the experimental targets. By transporting the positrons produced in these conversions as well as the electrons it is possible to almost double the number of photons delivered to the experiments per primary beam proton. 11 figs

  2. Radiated Emissions Test Approach

    Science.gov (United States)

    2015-10-02

    1. Draft Department of Transportation (DOT) Test Plan to Develop : Interference Tolerance Masks for GNSS Receivers in the L1 : Radiofrequency Band (1559 1610 MHz) provides high level : overview of radiated emissions test setup : 2. Presenta...

  3. A Compact Printed Quadruple Band-Notched UWB Antenna

    Directory of Open Access Journals (Sweden)

    Xiaoyin Li

    2013-01-01

    Full Text Available A novel compact coplanar waveguide- (CPW- fed ultrawideband (UWB printed planar volcano-smoke antenna (PVSA with four band-notches for various wireless applications is proposed and demonstrated. The low-profile antenna consists of a C-shaped parasitic strip to generate a notched band at 8.01~8.55 GHz for the ITU band, two C-shaped slots, and an inverted U-shaped slot etched in the radiator patch to create three notched bands at 5.15~5.35 GHz, 5.75~5.85 GHz, and 7.25~7.75 GHz for filtering the WLAN and X-band satellite signals. Simulated and measured results both confirm that the proposed antenna has a broad bandwidth of 3.1~12 GHz with VSWR < 2 and good omnidirectional radiation patterns with four notched-bands.

  4. Very compact quad band-notched UWB monopole antenna

    Science.gov (United States)

    Wu, Ling; Xia, Yingqing; Ye, Lei; Li, Lingzhi

    2016-10-01

    A very compact UWB antenna with four notched bands is proposed. The antenna consists of a rectangular radiating patch with a half circle at bottom, a tapered microstrip feed-line, and a semielliptical ground plane. With a pair of Lshaped slots, complementary co-directional SRR on the patch and a pair of L-shaped slots on the ground plane, four notched bands are created to prevent interference from WiMAX /WLAN/X-band. Experimental results show that the designed antenna, with compact size 20×30mm2, has an operating band(VSWR<2) from 2.7 to 20GHz,except four stop bands of 3.1 3.7GHz, 5.13 5.48GHz, 5.74 6.04GHz, 7.3 7.96GHz. And good radiation patterns within the operating band have been observed.

  5. High resolution color band pyrometer ratioing

    Science.gov (United States)

    Bickler, Donald B. (Inventor); Henry, Paul K. (Inventor); LoGiurato, D. Daniel (Inventor)

    1989-01-01

    The sensing head of a two-color band ratioing pyrometer of a known type using a fiber optic cable to couple radiation to dual detector photodiodes is improved to have high spatial resolution by focusing the radiation received through an objective lens (i.e., by focusing the image of a target area) onto an opaque sheet spaced in front of the input end of the fiber optic cable. A two-mil hole in that sheet then passes radiation to the input end of the cable. The detector has two channels, one for each color band, with an electronic-chopper stabilized current amplifier as the input stage followed by an electronic-chopper stabilized voltage amplifier.

  6. Band - Weg interactie

    NARCIS (Netherlands)

    de Boer, Andries; ter Huerne, Henderikus L.; Noordermeer, Jacobus W.M.; Schipper, Dirk J.; prof.dr.ir. Molenaar, A.A.A.

    2008-01-01

    De huidige infrastructuur van wegen waarover men zich snel en comfortabel kan verplaatsen is niet meer weg te denken uit onze maatschappij. Twee “componenten” die hierbij een belangrijke rol spelen zijn het wegdek en de band. Het contact tussen band en wegdek is mede bepalend voor de veiligheid. De

  7. Photonic band structure computations.

    Science.gov (United States)

    Hermann, D; Frank, M; Busch, K; Wolfle, P

    2001-01-29

    We introduce a novel algorithm for band structure computations based on multigrid methods. In addition, we demonstrate how the results of these band structure calculations may be used to compute group velocities and effective photon masses. The results are of direct relevance to studies of pulse propagation in such materials.

  8. ZEBRAFISH CHROMOSOME-BANDING

    NARCIS (Netherlands)

    PIJNACKER, LP; FERWERDA, MA

    1995-01-01

    Banding techniques were carried out on metaphase chromosomes of zebrafish (Danio rerio) embryos. The karyotypes with the longest chromosomes consist of 12 metacentrics, 26 submetacentrics, and 12 subtelocentrics (2n = 50). All centromeres are C-band positive. Eight chromosomes have a pericentric

  9. Usability Testing of Guided Internet-based Parent Training for Challenging Behavior in Children with Fetal Alcohol Spectrum Disorder (Strongest Families FASD).

    Science.gov (United States)

    Hundert, Amos S; Huguet, Anna; Green, Courtney R; Hewitt, Amy J; Mushquash, Christopher J; Muhajarine, Nazeem; Sourander, Andre; Caughey, Heather; Lingley-Pottie, Patricia; McGrath, Patrick J; Reynolds, James N

    2016-01-01

    In order to meet the need for accessible interventions and support for families affected by fetal alcohol spectrum disorder (FASD), we have developed an Internet-based, distance intervention for caregivers of children with FASD between the ages of four and twelve, called Strongest Families™ FASD. To evaluate the usability of the Strongest Families FASD program content and website in terms of learnability, efficiency and acceptability. A remote usability testing approach was conducted in two iterative cycles of participants. Synchronous online usability testing sessions were conducted, followed by asynchronous testing. A total of 18 participants were included, comprised of both health care professionals with expertise in FASD and caregivers of children with FASD. The data collected in each cycle was examined for commonalities and results were used to inform changes to the website and content after each cycle. Participants rated the website as appealing and relatively easy and fast to use. Nevertheless, several usability problems were identified such as difficulty navigating between sections of content on the website, displaying too much content per page, and the relevance and appropriateness of the content as it related to FASD. The identification of usability problems was an important step in refining the Strongest Families FASD program before its effectiveness is evaluated in a randomized controlled trial.

  10. Remote population-based intervention for disruptive behavior at age four: study protocol for a randomized trial of Internet-assisted parent training (Strongest Families Finland-Canada).

    Science.gov (United States)

    McGrath, Patrick J; Sourander, Andre; Lingley-Pottie, Patricia; Ristkari, Terja; Cunningham, Charles; Huttunen, Jukka; Filbert, Katharine; Aromaa, Minna; Corkum, Penny; Hinkka-Yli-Salomäki, Susanna; Kinnunen, Malin; Lampi, Katja; Penttinen, Anne; Sinokki, Atte; Unruh, Anita; Vuorio, Jenni; Watters, Carolyn

    2013-10-21

    Oppositional Defiant Disorder (ODD) is characterized by angry and noncompliant behaviour. It is the most common disruptive behaviour disorder (DBD), with prevalence estimates of 6-9% for preschoolers and is closely linked to several long-term difficulties, including disorders of conduct, mood, anxiety, impulse-control, and substance abuse. ODD in children is related to parental depression, family dysfunction, and impairments in parental work performance. Children displaying early DBDs exhibit more symptoms of greater severity, more frequent offences, and commit more serious crimes later in life. The goal of the Strongest Families Finland Canada (SFFC) Smart Website intervention research program is to develop and evaluate an affordable, accessible, effective secondary prevention parent training program for disruptive behaviour in preschoolers to prevent the negative sequelae of ODD. Strongest Families is an 11-session program with two booster sessions that focuses on teaching skills to: strengthen parent-child relationships; reinforce positive behaviour; reduce conflict; manage daily transitions; plan for potentially problematic situations; promote emotional regulation and pro-social behaviour and decrease antisocial behaviour. This protocol paper describes an ongoing population-based randomized controlled trial (RCT) of high-risk 4 year-olds attending well-child clinics in Turku, Finland and environs to examine the effectiveness of the Strongest Families Smart Website intervention compared to an Education Control condition. Randomization consists of a 1:1 ratio for intervention versus the education group, stratified by the child's sex. The participants randomized to the intervention group receive access to the Strongest Families Smart Website and weekly telephone coaching sessions. The participants randomized to the Education Control condition receive access to a static website with parenting tips. Children are followed using parental and daycare teacher measures

  11. Band parameters of phosphorene

    DEFF Research Database (Denmark)

    Lew Yan Voon, L. C.; Wang, J.; Zhang, Y.

    2015-01-01

    Phosphorene is a two-dimensional nanomaterial with a direct band-gap at the Brillouin zone center. In this paper, we present a recently derived effective-mass theory of the band structure in the presence of strain and electric field, based upon group theory. Band parameters for this theory...... are computed using a first-principles theory based upon the generalized-gradient approximation to the density-functional theory. These parameters and Hamiltonian will be useful for modeling physical properties of phosphorene....

  12. Laparoscopic gastric banding

    Science.gov (United States)

    ... eat by making you feel full after eating small amounts of food. After surgery, your doctor can adjust the band ... You will feel full after eating just a small amount of food. The food in the small upper pouch will ...

  13. Decay of superdeformed bands

    International Nuclear Information System (INIS)

    Carpenter, M.P.; Khoo, T.L.; Lauritsen, T.

    1995-01-01

    One of the major challenges in the study of superdeformation is to directly connect the large number of superdeformed bands now known to the yrast states. In this way, excitation energies, spins and parities can be assigned to the levels in the second well which is essential to establish the collective and single-particle components of these bands. This paper will review some of the progress which has been made to understand the decay of superdeformed bands using the new arrays including the measurement of the total decay spectrum and the establishment of direct one-step decays from the superdeformed band to the yrast line in 194 Hg. 42 refs., 5 figs

  14. HYBASE - HYperspectral BAnd SElection tool

    NARCIS (Netherlands)

    Schwering, P.B.W.; Bekman, H.H.P.T.; Seijen, H.H. van

    2008-01-01

    Band selection is essential in the design of multispectral sensor systems. This paper describes the TNO hyperspectral band selection tool HYBASE. It calculates the optimum band positions given the number of bands and the width of the spectral bands. HYBASE is used to calculate the minimum number of

  15. Hurricane Spiral Bands.

    Science.gov (United States)

    Guinn, Thomas A.; Schubert, Wayne H.

    1993-10-01

    The spiral bands that occur in tropical cyclones can be conveniently divided into two classes-outer bands and inner bands. Evidence is presented here that the outer bands form as the result of nonlinear effects during the breakdown of the intertropical convergence zone (ITCZ) through barotropic instability. In this process a zonal strip of high potential vorticity (the ITCZ shear zone or monsoon trough) begins to distort in a varicose fashion, with the potential vorticity (PV) becoming pooled in local regions that are connected by filaments of high PV. As the pooled regions become more axisymmetric, the filaments become thinner and begin to wrap around the PV centers.It is argued that inner bands form in a different manner. As a tropical cyclone intensifies due to latent heat release, the PV field becomes nearly circular with the highest values of PV in the cyclone center. The radial gradient of PV provides a state on which PV waves (the generalization of Rossby waves) can propagate. The nonlinear breaking of PV waves then leads to an irreversible distortion of the PV contours and a downgradient flux of PV. The continuation of this proem tends to erode the high PV core of the tropical cyclone, to produce a surrounding surf zone, and hence to spread the PV horizontally. In a similar fashion, inner bands can also form by the merger of a vortex with a patch of relatively high PV air. As the merger proem occurs the patch of PV is quickly elongated and wrapped around the vortex. The resulting vortex is generally larger in horizontal extent and exhibits a spiral band of PV.When the formation of outer and inner bands is interpreted in the context of a normal-mode spectral model, they emerge as slow manifold phenomena; that is, they have both rotational and (balanced or slaved) gravitational mode aspects. In this sense, regarding them as simply gravity waves leads to an incomplete dynamical picture.

  16. Strongest magnet in the cosmos

    CERN Document Server

    Zane, S

    2003-01-01

    In November 1996 a NASA satellite called the Rossi X-ray Timing Explorer (RXTE) was monitoring a rare type of pulsar some 40 000 light-years from Earth. The star, called SGR 1806-20, is one of just four known 'soft gamma repeaters' - rotating neutron stars that periodically emit huge bursts of gamma rays. Now an international team of astrophysicists studying the RXTE data has found evidence for what is known as a magnetar - the most magnetic object in the universe. (U.K.)

  17. A Small UWB Antenna with Dual Band-Notched Characteristics

    Directory of Open Access Journals (Sweden)

    J. Xu

    2012-01-01

    Full Text Available A small novel ultrawideband (UWB antenna with dual band-notched functions is proposed. The dual band rejection is achieved by etching two C-shaped slots on the radiation patch with limited area. A single band-notched antenna is firstly presented, and then an optimized dual band-notched antenna is presented and analyzed. The measured VSWR shows that the proposed antenna could operate from 3.05 to 10.7 GHz with VSWR less than 2, except two stopbands at 3.38 to 3.82 GHz and 5.3 to 5.8 GHz for filtering the WiMAX and WLAN signals. Radiation patterns are simulated by HFSS and verified by CST, and quasiomnidirectional radiation patterns in the H-plane could be observed. Moreover, the proposed antenna has a very compact size and could be easily integrated into portable UWB devices.

  18. Observations of 40-70 micron bands of ice in IRAS 09371 + 1212 and other stars

    Science.gov (United States)

    Omont, A.; Forveille, T.; Moseley, S. H.; Glaccum, W. J.; Harvey, P. M.; Likkel, L.; Loewenstein, R. F.; Lisse, C. M.

    1990-01-01

    IRAS 09371 + 1212 is still an absolutely unique object. This M giant star, with circumstellar CO and a spectacular bipolar nebula, displays unique IRAS FIR colors which had been attributed to strong emission in the 40-70-micron bands of ice, as subsequently supported by the observation of a strong 3.1-micron absorption band. The results of the KAO observations have confirmed its unusual nature: the far-infrared bands of ice are by far the strongest known. Its dust temperature, 50 K or less, is by far the lowest known for a late-type circumstellar envelope.

  19. Photonic band gap materials

    Science.gov (United States)

    Cassagne, D.

    Photonic band gap materials Photonic band gap materials are periodic dielectric structures that control the propagation of electromagnetic waves. We describe the plane wave method, which allows to calculate the band structures of photonic crystals. By symmetry analysis and a perturbative approach, we predict the appearance of the low energy photonic band gaps of hexagonal structures. We propose new two-dimensional structures called graphite and boron nitride. Using a transfer matrix method, we calculate the transmission of the graphite structure and we show the crucial role of the coupling with external modes. We study the appearance of allowed modes in the photonic band gap by the introduction of localized defects in the periodicity. Finally, we discuss the properties of opals formed by self-organized silica microspheres, which are very promising for the fabrication of three-dimensional photonic crystals. Les matériaux à bandes interdites photoniques sont des structures diélectriques périodiques qui contrôlent la propagation des ondes électromagnétiques. Nous décrivons la méthode des ondes planes qui permet de calculer les structures de bandes des cristaux photoniques. Par une analyse de la symétrie et une approche perturbative, nous précisons les conditions d'existence des bandes interdites de basse énergie. Nous proposons de nouvelles structures bidimensionnelles appelées graphite et nitrure de bore. Grâce à une méthode de matrices de transfert, nous calculons la transmission de la structure graphite et nous mettons en évidence le rôle fondamental du couplage avec les modes extérieurs. Nous étudions l'apparition de modes permis dans la bande interdite grâce à l'introduction de défauts dans la périodicité. Enfin, nous discutons les propriétés des opales constituées de micro-billes de silice auto-organisées, qui sont très prometteuses pour la fabrication de cristaux photoniques tridimensionnels.

  20. Investigation of PLC band nucleation in AA5754

    Energy Technology Data Exchange (ETDEWEB)

    Feng, X., E-mail: Xiaoqun.Feng@tu-dortmund.de [Technische Universitaet Dortmund, Fakultaet Maschinenbau, Lehrstuhl fuer Werkstofftechnologie, D-44221 Dortmund (Germany); Fischer, G., E-mail: Gottfried.Fischer@rif-ev.de [RIF e.V., Joseph-von-Fraunhofer-Str. 20, D-44227 Dortmund (Germany); Zielke, R., E-mail: Reiner.Zielke@tu-dortmund.de [Technische Universitaet Dortmund, Fakultaet Maschinenbau, Lehrstuhl fuer Werkstofftechnologie, D-44221 Dortmund (Germany); Svendsen, B., E-mail: Bob.Svendsen@udo.edu [Technische Universitaet Dortmund, Fakultaet Maschinenbau, Lehrstuhl fuer Mechanik, D-44221 Dortmund (Germany); Tillmann, W., E-mail: Wolfgang.Tillmann@udo.edu [Technische Universitaet Dortmund, Fakultaet Maschinenbau, Lehrstuhl fuer Werkstofftechnologie, D-44221 Dortmund (Germany)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer Simultaneous propagation of bands in transverse and longitudinal directions. Black-Right-Pointing-Pointer PLC band nucleation at the back front of Lueders bands. Black-Right-Pointing-Pointer Characteristic time of critical strain decreases with strain rate. Black-Right-Pointing-Pointer Simultaneous existence of two type-B bands at specimen shoulder. - Abstract: The purpose of the present work is the experimental investigation of the nucleation of PLC deformation bands in the aluminium alloy AA5754. The PLC bands are investigated using both mechanical methods and infrared (IR) thermography. The latter employs a high-speed IR camera which captures local changes of radiated power resulting from mechanical dissipation and heating due to the nucleation of PLC bands. The resulting IR images are used to determine spatio-temporal power field variations via image subtraction. Furthermore, band trajectories obtained from the IR images are used to study possible correlations between the spatio-temporal evolution of stress and radiated power in the specimens and PLC band development.

  1. Restrictive techniques: gastric banding

    Directory of Open Access Journals (Sweden)

    Katia Cristina da Cunha

    2006-03-01

    Full Text Available Surgery for the treatment of severe obesity has a definite role onthe therapeutic armamentarium all over the world. Initiated 40years ago, bariatric surgery has already a long way thanks tohundred of surgeons, who had constantly searched for the besttechnique for the adequate control of severe obesity. Among theimportant breakthroughs in obesity surgery there is theadjustable gastric band. It is a sylastic band, inflatable andadjustable, which is placed on the top of the stomach in order tocreate a 15-20 cc pouch, with an outlet of 1.3cm. The adjustablegastric band has also a subcutaneous reservoir through whichadjustments can be made, according to the patient evolution.The main feature of the adjustable gastric band is the fact thatis minimal invasive, reversible, adjustable and placedlaparoscopically. Then greatly diminishing the surgical traumato the severe obese patient. Belachew and Favretti’s techniqueof laparoscopic application of the adjustable gastric band isdescribed and the evolution of the technique during this years,as we has been practiced since 1998. The perioperative care ofthe patient is also described, as well as the follow-up and shortand long term controls.

  2. Ultra wide band antennas

    CERN Document Server

    Begaud, Xavier

    2013-01-01

    Ultra Wide Band Technology (UWB) has reached a level of maturity that allows us to offer wireless links with either high or low data rates. These wireless links are frequently associated with a location capability for which ultimate accuracy varies with the inverse of the frequency bandwidth. Using time or frequency domain waveforms, they are currently the subject of international standards facilitating their commercial implementation. Drawing up a complete state of the art, Ultra Wide Band Antennas is aimed at students, engineers and researchers and presents a summary of internationally recog

  3. Review of wide band-gap semiconductors technology

    Directory of Open Access Journals (Sweden)

    Jin Haiwei

    2016-01-01

    Full Text Available Silicon carbide (SiC and gallium nitride (GaN are typical representative of the wide band-gap semiconductor material, which is also known as third-generation semiconductor materials. Compared with the conventional semiconductor silicon (Si or gallium arsenide (GaAs, wide band-gap semiconductor has the wide band gap, high saturated drift velocity, high critical breakdown field and other advantages; it is a highly desirable semiconductor material applied under the case of high-power, high-temperature, high-frequency, anti-radiation environment. These advantages of wide band-gap devices make them a hot spot of semiconductor technology research in various countries. This article describes the research agenda of United States and European in this area, focusing on the recent developments of the wide band-gap technology in the US and Europe, summed up the facing challenge of the wide band-gap technology.

  4. UV Radiation and Sun Exposure | RadTown USA | US EPA

    Science.gov (United States)

    2017-08-07

    Tanning is your body's attempt to protect itself from being damaged by ultraviolet radiation. Too much ultraviolet radiation (UV) from sunlight is dangerous. Nearly half of UV radiation is received between 10 a.m. and 4 p.m., when the sun's rays are the strongest. Even on a cloudy day, you can be sunburned by UV radiation.

  5. A Coplanar Waveguide Fed Hexagonal Shape Ultra Wide Band Antenna with WiMAX and WLAN Band Rejection

    Directory of Open Access Journals (Sweden)

    T. Mandal

    2014-12-01

    Full Text Available In this paper, a coplanar waveguide (CPW fed hexagonal shape planar antenna has been considered for ultra-wide band (UWB. This antenna is then modified to obtain dual band rejection. The Wireless Local Area Network (WLAN and Wireless Microwave Access (WiMAX band rejections are realized by symmetrically incorporating a pair of L-shape slots within the ground plane as well as a couple of I-shape stubs inserted on the bottom side of radiating patch. The proposed antenna has stop bands of 5.05-5.92 GHz and 3.19-3.7 GHz while maintaining the wideband performance from 2.88 - 13.71 GHz with reflection coefficient of ≤ -10 dB. The antenna exhibits satisfactory omni-directional radiation characteristics throughout its operating band. The peak gain varies from 2 dB to 6 dB in the entire UWB frequency regions except at the notch bands. Surface current distributions are used to analyze the effects of the L-slot and I-shape stub. The measured group delay has small variation within the operating band except notch bands and hence the proposed antenna may be suitable for UWB applications.

  6. Silicon radiation detector

    International Nuclear Information System (INIS)

    Benc, I.; Kerhart, J.; Kopecky, J.; Krca, P.; Veverka, V.; Weidner, M.; Weinova, H.

    1992-01-01

    The silicon radiation detector, which is designed for the detection of electrons with energies above 500 eV and of radiation within the region of 200 to 1100 nm, comprises a PIN or PNN + type photodiode. The active acceptor photodiode is formed by a detector surface of shallow acceptor diffusion surrounded by a collector band of deep acceptor diffusion. The detector surface of shallow P-type diffusion with an acceptor concentration of 10 15 to 10 17 atoms/cm 3 reaches a depth of 40 to 100 nm. One sixth to one eighth of the collector band width is overlapped by the P + collector band at a width of 150 to 300 μm with an acceptor concentration of 10 20 to 10 21 atoms/cm 3 down a depth of 0.5 to 3 μm. This band is covered with a conductive layer, of NiCr for instance. (Z.S.)

  7. Theoretical band alignment in an intermediate band chalcopyrite based material

    Science.gov (United States)

    Castellanos Águila, J. E.; Palacios, P.; Conesa, J. C.; Arriaga, J.; Wahnón, P.

    2017-12-01

    Band alignment is key to enhance the performance of heterojunction for chalcopyrite thin film solar cells. In this paper we report ab initio calculations of the electronic structures of CuGaS2:Cr with various Cr compositions, CuAlSe2 and ZnSe and the band alignment between their interfaces. We use density functional theory and the more accurate self-consistent GW scheme to obtain improved bulk band-gaps and band offsets. Band alignments of the interfacial region for CuGaS2:Cr/CuAlSe2 and CuGaS2:Cr/ZnSe systems were aligned with respect of an average electrostatic potential. Our results are in good agreement with experimental values for the bulk band-gaps. These theoretical band alignments show a characteristic staggered band alignment for the design of heterojunction devices in photovoltaic applications.

  8. Compact Size UWB Monopole Antenna with Triple Band-Notches

    OpenAIRE

    Ali, W.; Ibrahim, A. A.; Machac, J.

    2017-01-01

    This paper presents triple band notched ultra wide band (UWB) monopole antenna with overall size of 36 × 32 mm2 fed by microstrip transmission line. In order to achieve a good impedance matching from 2.7 GHz to 13.4 GHz, a tapered transition between the rectangular patch and the feeding line is utilized. The three notched frequency bands are accomplished by a defected microstrip structure (DMS) which is inserted in the microstrip feeding line and by an open loop slot etched in the radiating p...

  9. Semiconductors bonds and bands

    CERN Document Server

    Ferry, David K

    2013-01-01

    As we settle into this second decade of the twenty-first century, it is evident that the advances in micro-electronics have truly revolutionized our day-to-day lifestyle. The technology is built upon semiconductors, materials in which the band gap has been engineered for special values suitable to the particular application. This book, written specifically for a one semester course for graduate students, provides a thorough understanding of the key solid state physics of semiconductors. It describes how quantum mechanics gives semiconductors unique properties that enabled the micro-electronics revolution, and sustain the ever-growing importance of this revolution.

  10. Microstrip microwave band gap structures

    Indian Academy of Sciences (India)

    Microwave band gap structures exhibit certain stop band characteristics based on the periodicity, impedance contrast and effective refractive index contrast. These structures though formed in one-, two- and three-dimensional periodicity, are huge in size. In this paper, microstrip-based microwave band gap structures are ...

  11. A Smile Face Monopole Antenna with Quadruple Band-Notched Characteristics

    Science.gov (United States)

    Yang, Xiao-Lin; Kong, Fang-Ling; Wang, Yan

    2015-05-01

    A compact planar ultra-wideband (UWB) monopole antenna with quadruple band-notched characteristics is presented. The notched band at 3.3-4.2 GHz (C-band) is obtained by embedding a pair of Z-shaped slots on the elliptical radiation patch. Meanwhile, a modified U-shaped slot is etched in the radiation patch to create the notched band at 4.9-5.4 GHz for WLAN. In addition, by introducing E-shaped stubs on the back layer, the notched bands at 5.5-6.1 GHz for WLAN and 7-8.15 GHz for downlink of X-band satellite communication system are obtained. The antenna is fabricated and measured, showing broadband matched impedance and good Omni-directional patterns with high fidelity and phase linearity (outside the notched bands).

  12. Morphologies of omega band auroras

    Science.gov (United States)

    Sato, Natsuo; Yukimatu, Akira Sessai; Tanaka, Yoshimasa; Hori, Tomoaki

    2017-08-01

    We examined the morphological signatures of 315 omega band aurora events observed using the Time History of Events and Macroscale Interactions during Substorm ground-based all-sky imager network over a period of 8 years. We find that omega bands can be classified into the following three subtypes: (1) classical (O-type) omega bands, (2) torch or tongue (T-type) omega bands, and (3) combinations of classical and torch or tongue (O/T-type) omega bands. The statistical results show that T-type bands occur the most frequently (45%), followed by O/T-type bands (35%) and O-type bands (18%). We also examined the morphologies of the omega bands during their formation, from the growth period to the declining period through the maximum period. Interestingly, the omega bands are not stable, but rather exhibit dynamic changes in shape, intensity, and motion. They grow from small-scale bumps (seeds) at the poleward boundary of preexisting east-west-aligned auroras, rather than via the rotation or shear motion of preexisting east-west-aligned auroras, and do not exhibit any shear motion during the periods of auroral activity growth. Furthermore, the auroral luminosity is observed to increase during the declining period, and the total time from the start of the growth period to the end of the declining period is found to be about 20 min. Such dynamical signatures may be important in determining the mechanism responsible for omega band formation.

  13. Obituary: David L. Band (1957-2009)

    Science.gov (United States)

    Cominsky, Lynn

    2011-12-01

    David L. Band, of Potomac Maryland, died on March 16, 2009 succumbing to a long battle with spinal cord cancer. His death at the age of 52 came as a shock to his many friends and colleagues in the physics and astronomy community. Band showed an early interest and exceptional aptitude for physics, leading to his acceptance at the Massachusetts Institute of Technology as an undergraduate student in 1975. After graduating from MIT with an undergraduate degree in Physics, Band continued as a graduate student in Physics at Harvard University. His emerging interest in Astrophysics led him to the Astronomy Department at the Harvard Smithsonian Center for Astrophysics (CfA), where he did his dissertation work with Jonathan Grindlay. His dissertation (1985) entitled "Non-thermal Radiation Mechanisms and Processes in SS433 and Active Galactic Nuclei" was "pioneering work on the physics of jets arising from black holes and models for their emission, including self-absorption, which previewed much to come, and even David's own later work on Gamma-ray Bursts," according to Grindlay who remained a personal friend and colleague of Band's. Following graduate school, Band held postdoctoral positions at the Lawrence Livermore Laboratory, the University of California at Berkeley and the Center for Astronomy and Space Sciences at the University of California San Diego where he worked on the BATSE experiment that was part of the Compton Gamma Ray Observatory (CGRO), launched in 1991. BATSE had as its main objective the study of cosmic gamma-ray bursts (GRBs) and made significant advances in this area of research. Band became a world-renowned figure in the emerging field of GRB studies. He is best known for his widely-used analytic form of gamma-ray burst spectra known as the "Band Function." After the CGRO mission ended, Band moved to the Los Alamos National Laboratory where he worked mainly on classified research but continued to work on GRB energetics and spectra. When NASA planned

  14. The 9.2 ka event in Asian summer monsoon area: the strongest millennial scale collapse of the monsoon during the Holocene

    Science.gov (United States)

    Zhang, Wenchao; Yan, Hong; Dodson, John; Cheng, Peng; Liu, Chengcheng; Li, Jianyong; Lu, Fengyan; Zhou, Weijian; An, Zhisheng

    2018-04-01

    Numerous Holocene paleo-proxy records exhibit a series of centennial-millennial scale rapid climatic events. Unlike the widely acknowledged 8.2 ka climate anomaly, the likelihood of a significant climate excursion at around 9.2 cal ka BP, which has been notably recognized in some studies, remains to be fully clarified in terms of its magnitude and intensity, as well as its characteristics and spatial distributions in a range of paleoclimatic records. In this study, a peat sediment profile from the Dajiuhu Basin in central China was collected with several geochemical proxies and a pollen analysis carried out to help improve understanding of the climate changes around 9.2 cal ka BP. The results show that the peat development was interrupted abruptly at around 9.2 cal ka BP, when the chemical weathering strength decreased and the tree-pollen declined. This suggests that a strong drier regional climatic event occurred at around 9.2 cal ka BP in central China, which was, in turn, probably connected to the rapid 9.2 ka climate event co-developing worldwide. In addition, based on the synthesis of our peat records and the other Holocene hydrological records from Asian summer monsoon (ASM) region, we further found that the 9.2 ka event probably constituted the strongest abrupt collapse of the Asian monsoon system during the full Holocene interval. The correlations between ASM and the atmospheric 14C production rate, the North Atlantic drift ice records and Greenland temperature indicated that the weakened ASM event at around 9.2 cal ka BP could be interpreted by the co-influence of external and internal factors, related to the changes of the solar activity and the Atlantic Meridional Overturning Circulation (AMOC).

  15. The 9.2 ka event in Asian summer monsoon area: the strongest millennial scale collapse of the monsoon during the Holocene

    Science.gov (United States)

    Zhang, Wenchao; Yan, Hong; Dodson, John; Cheng, Peng; Liu, Chengcheng; Li, Jianyong; Lu, Fengyan; Zhou, Weijian; An, Zhisheng

    2017-06-01

    Numerous Holocene paleo-proxy records exhibit a series of centennial-millennial scale rapid climatic events. Unlike the widely acknowledged 8.2 ka climate anomaly, the likelihood of a significant climate excursion at around 9.2 cal ka BP, which has been notably recognized in some studies, remains to be fully clarified in terms of its magnitude and intensity, as well as its characteristics and spatial distributions in a range of paleoclimatic records. In this study, a peat sediment profile from the Dajiuhu Basin in central China was collected with several geochemical proxies and a pollen analysis carried out to help improve understanding of the climate changes around 9.2 cal ka BP. The results show that the peat development was interrupted abruptly at around 9.2 cal ka BP, when the chemical weathering strength decreased and the tree-pollen declined. This suggests that a strong drier regional climatic event occurred at around 9.2 cal ka BP in central China, which was, in turn, probably connected to the rapid 9.2 ka climate event co-developing worldwide. In addition, based on the synthesis of our peat records and the other Holocene hydrological records from Asian summer monsoon (ASM) region, we further found that the 9.2 ka event probably constituted the strongest abrupt collapse of the Asian monsoon system during the full Holocene interval. The correlations between ASM and the atmospheric 14C production rate, the North Atlantic drift ice records and Greenland temperature indicated that the weakened ASM event at around 9.2 cal ka BP could be interpreted by the co-influence of external and internal factors, related to the changes of the solar activity and the Atlantic Meridional Overturning Circulation (AMOC).

  16. Wide band ENDOR spectrometer

    International Nuclear Information System (INIS)

    Mendonca Filho, C.

    1973-01-01

    The construction of an ENDOR spectrometer operating from 0,5 to 75 MHz within a single band, with ore Klystron and homodine detection, and no fundamental changes on the electron spin resonance spectrometer was described. The ENDOR signal can be detected both by amplitude modulation of the frequency field, or direct detection of the ESR output, which is taken to a signal analyser. The signal-to-noise ratio is raised by averaging rather than filtering avoiding the use of long time constants, providing natural line widths. The experimental apparatus and the spectra obtained are described. A discussion, relating the ENDOR line amplitudes with the experimental conditions is done and ENDOR mechanism, in which there is a relevant presence of cross relaxation is proposed

  17. Wide Band Artificial Pulsar

    Science.gov (United States)

    Parsons, Zackary

    2017-01-01

    The Wide Band Artificial Pulsar (WBAP) is an instrument verification device designed and built by the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virgina. The site currently operates the Green Bank Ultimate Pulsar Processing Instrument (GUPPI) and the Versatile Green Bank Astronomical Spectrometer (VEGAS) digital backends for their radio telescopes. The commissioning and continued support for these sophisticated backends has demonstrated a need for a device capable of producing an accurate artificial pulsar signal. The WBAP is designed to provide a very close approximation to an actual pulsar signal. This presentation is intended to provide an overview of the current hardware and software implementations and to also share the current results from testing using the WBAP.

  18. Advances in X-Band and S-Band Linear Accelerators for Security, NDT, and Other Applications

    CERN Document Server

    Mishin, Andrey V

    2005-01-01

    At AS&E High Energy Systems Division, we designed several new advanced high energy electron beam and X-ray sources. Our primary focus has always been in building the world's most portable commercial X-band accelerators. Today, our X-band systems frequently exceed performance of the similar S-band machines, while they are more portable compared to the latter. The new designs of the X-band accelerators in the most practical energy range from 1 MeV to 6 MeV have been tested delivering outstanding results. Seventy 6 MeV X-band linacs systems have been produced. The most compact linac for security is used by AS&E in a self-shielded, Shaped Energy™ cargo screening system. We pioneered using the X-band linear accelerators for CT, producing high quality images of oil pipes and wood logs. An X-band linear accelerator head on a robotic arm has been used for electron beam radiation curing of an odd-shaped graphite composite part. We developed the broad-range 4 MeV to over 10 MeV energy-regulated X-band ...

  19. Thermodynamics of Radiation Modes

    Science.gov (United States)

    Pina, Eduardo; de la Selva, Sara Maria Teresa

    2010-01-01

    We study the equilibrium thermodynamics of the electromagnetic radiation in a cavity of a given volume and temperature. We found three levels of description, the thermodynamics of one mode, the thermodynamics of the distribution of frequencies in a band by summing over the frequencies in it and the global thermodynamics by summing over all the…

  20. The Wide Band-Gap Semiconductors: A Brief Survey | Ottaviani ...

    African Journals Online (AJOL)

    The wide band-gap semiconductors are promising materials in the fields of power electronics, high-energy radiation detection and optoelectronics. They have attracted much attention thanks to their physical properties, allowing them to get better performances than silicon for some specific uses (high temperature, high ...

  1. Compact Size UWB Monopole Antenna with Triple Band-Notches

    Directory of Open Access Journals (Sweden)

    W. Ali

    2017-04-01

    Full Text Available This paper presents triple band notched ultra wide band (UWB monopole antenna with overall size of 36 × 32 mm2 fed by microstrip transmission line. In order to achieve a good impedance matching from 2.7 GHz to 13.4 GHz, a tapered transition between the rectangular patch and the feeding line is utilized. The three notched frequency bands are accomplished by a defected microstrip structure (DMS which is inserted in the microstrip feeding line and by an open loop slot etched in the radiating patch. The three band notches are 3.15-4 GHz, 5.7-6.3 GHz and 7.9-8.6 GHz. They prevent the receiving of the signals of IEEE 802.16 WiMAX band, WLAN band, and ITU applications respectively. The UWB antenna was designed and simulated then fabricated and tested in order to investigate its impedance and radiation characteristics. Good agreement between the simulated and measured data is achieved. The obtained results show that the proposed antenna is convenient for UWB applications.

  2. Double positivity for HPV-DNA/p16ink4ais the biomarker with strongest diagnostic accuracy and prognostic value for human papillomavirus related oropharyngeal cancer patients.

    Science.gov (United States)

    Mena, Marisa; Taberna, Miren; Tous, Sara; Marquez, Sandra; Clavero, Omar; Quiros, Beatriz; Lloveras, Belen; Alejo, Maria; Leon, Xavier; Quer, Miquel; Bagué, Silvia; Mesia, Ricard; Nogués, Julio; Gomà, Montserrat; Aguila, Anton; Bonfill, Teresa; Blazquez, Carmen; Guix, Marta; Hijano, Rafael; Torres, Montserrat; Holzinger, Dana; Pawlita, Michael; Pavon, Miguel Angel; Bravo, Ignacio G; de Sanjosé, Silvia; Bosch, Francesc Xavier; Alemany, Laia

    2018-03-01

    The etiologic role of human papillomaviruses (HPV) in oropharyngeal cancer (OPC) is well established. Nevertheless, information on survival differences by anatomic sub-site or treatment remains scarce, and it is still unclear the HPV-relatedness definition with best diagnostic accuracy and prognostic value. We conducted a retrospective cohort study of all patients diagnosed with a primary OPC in four Catalonian hospitals from 1990 to 2013. Formalin-fixed, paraffin-embedded cancer tissues were subjected to histopathological evaluation, DNA quality control, HPV-DNA detection, and p16 INK4a /pRb/p53/Cyclin-D1 immunohistochemistry. HPV-DNA positive and a random sample of HPV-DNA negative cases were subjected to HPV-E6*I mRNA detection. Demographic, tobacco/alcohol use, clinical and follow-up data were collected. Multivariate models were used to evaluate factors associated with HPV positivity as defined by four different HPV-relatedness definitions. Proportional-hazards models were used to compare the risk of death and recurrence among HPV-related and non-related OPC. 788 patients yielded a valid HPV-DNA result. The percentage of positive cases was 10.9%, 10.2%, 8.5% and 7.4% for p16 INK4a , HPV-DNA, HPV-DNA/HPV-E6*I mRNA, and HPV-DNA/p16 INK4a , respectively. Being non-smoker or non-drinker was consistently associated across HPV-relatedness definitions with HPV positivity. A suggestion of survival differences between anatomic sub-sites and treatments was observed. Double positivity for HPV-DNA/p16 INK4a showed strongest diagnostic accuracy and prognostic value. Double positivity for HPV-DNA/p16 INK4a , a test that can be easily implemented in the clinical practice, has optimal diagnostic accuracy and prognostic value. Our results have strong clinical implications for patients' classification and handling and also suggest that not all the HPV-related OPC behave similarly. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Brief Report: Lopinavir Hair Concentrations Are the Strongest Predictor of Viremia in HIV-Infected Asian Children and Adolescents on Second-Line Antiretroviral Therapy.

    Science.gov (United States)

    Pintye, Jillian; Bacchetti, Peter; Teeraananchai, Sirinya; Kerr, Stephen; Prasitsuebsai, Wasana; Singtoroj, Thida; Kuncze, Karen; Louie, Alexander; Koss, Catherine A; Jin, Chengshi; Phung, Nhi; Horng, Howard; Sohn, Annette H; Gandhi, Monica

    2017-12-01

    Children/adolescents display suboptimal antiretroviral therapy (ART) adherence and outcomes versus adults. Hair ART concentrations are objective adherence measures that predict viremia in adults but longitudinal data on hair levels in pediatric populations is limited. We assessed the predictive utility of hair lopinavir (LPV) levels on viremia among youth on second-line ART. We examined predictors of viremia (HIV-1 RNA >400 and >1000 copies/mL) at least 24 weeks after switch to LPV-based second-line ART in a cohort of HIV-infected Asian children followed between 2011 and 2014. Small hair samples, HIV-1 RNA, and self-reported adherence were collected biannually. Hair concentrations of LPV were measured through liquid chromatography/tandem mass spectrometry using validated methods. Time-to-first viremia was examined using discrete-time Cox models. Overall, 244 children met the inclusion criteria for the present analysis. Approximately half (55%) were boys and the median age 10 years [interquartile range (IQR) 7-13]; 40% were older than 11 years. At switch to second-line ART, median CD4 count was 300 (IQR 146-547) cells/mm and median HIV-RNA level was 5.0 (IQR 4.3-5.6) log10/mL. Median time of study follow-up was 48 weeks and a median of 3 (range 1-5) hair samples were collected from each participant. Adjusting for age, sex, country, self-reported adherence, CD4, and HIV-RNA, higher LPV hair concentrations were the strongest predictor of lower odds of viremia (HIV-RNA >400 copies/mL adjusted odds ratio = 0.41 per doubling in hair concentration, 95% confidence interval: 0.29 to 0.58, P 1000 copies/mL, adjusted odds ratio = 0.54, 95% confidence interval: 0.45 to 0.65, P Hair concentrations predict viremia among children with HIV on second-line ART and could guide clinical decisions for this population.

  4. Optical radiation in modern medicine

    OpenAIRE

    Sowa, Pawe?; Rutkowska-Talipska, Joanna; Rutkowski, Krzysztof; Koszty?a-Hojna, Bo?ena; Rutkowski, Ryszard

    2013-01-01

    Optical radiation extends between microwaves and X-rays of the electromagnetic radiation and includes ultraviolet (UV), visible light (VL) and infrared (IR) components. The dose of radiation that reaches the skin is influenced by the ozone layer, position of the Sun, latitude, altitude, cloud cover and ground reflections. The photobiological effects of UV, VL and IR bands depend on their wavelength, frequency and mechanism of action. They are modified by the thickness, structure, vasculature ...

  5. Non-spherical surface wave amplitude radiation patterns identified from spectral ratios of the 2016 and 2013 DPRK nuclear tests

    Science.gov (United States)

    Ichinose, G. A.; Ford, S. R.; Myers, S.; Pasyanos, M.; Walter, W. R.

    2016-12-01

    The 6 January 2016, 12 February 2013 and 25 May 2009 declared nuclear explosions at the Punggye-ri test site in the Democratic People's Republic of Korea (DPRK) were all closely located providing an opportunity to perform differential analysis. We used spectral ratios of surface waves between 50 and 10 sec period between the co-located events to isolate relative explosion amplitude radiation patterns by the cancelation of propagation and site effects. We calculated the spectral ratios using a dense array of 72 NIED F-NET stations across Japan and all available IMS, IC and IU network stations. Analyses of Rayleigh waves indicated non-spherical radiation for the 2016 and 2013 tests relative to 2009. The 2016/2009 and 2013/2009 event pairs had ellipsoidal radiation patterns. The 2016/2009 pair had an ellipse major axis oriented 123 degrees from north and the 2013/2009 pair was oriented 33 degrees from north. This suggests that both 2016 and 2013 explosions have non-spherical radiation and also that the radiation between 2016 and 2013 were rotated by 90 degrees. This radiation pattern was strongest in the 20 and 33 sec period band but was also observed in the 10 and 50 sec band with higher scatter. We did not discern any Love wave radiation patterns but there is high scatter possibly due to a lower long-period signal to noise ratio on the horizontal relative to the vertical components. There are several possible source models that can theoretically cause non-spherical radiation, for example topography, spall damage, or tectonic release. One implication we have identified is that the radiation pattern makes it problematic for the use of surface waves in relative relocations, typically more robust for earthquakes. The amount of departure from purely spherical radiation is consistent with the 20-30% CLVD and 60-70% isotropic components estimated from regional long-period moment tensor solutions for the two explosions. This work performed under the auspices of the US

  6. Two-Port Dual-Band Microstrip Square-Ring Antenna for Radar Applications

    NARCIS (Netherlands)

    Puskely, J.; Yarovyi, O.; Roederer, A.G.; Mattes, Michael

    A novel two-port, dual-band square-ring microstrip antenna element for wide-angle scanning planar phased array is proposed. The two ports are used to operate the antenna array over the L and S radar bands. Microstrip square-ring radiators are chosen due to their smaller dimensions compared to the

  7. Dual-band infrared camera

    Science.gov (United States)

    Vogel, H.; Schlemmer, H.

    2005-10-01

    Every year, numerous accidents happen on European roads due to bad visibility (fog, night, heavy rain). Similarly, the dramatic aviation accidents of year 2001 in Milan and Zurich have reminded us that aviation safety is equally affected by reduced visibility. A dual-band thermal imager was developed in order to raise human situation awareness under conditions of reduced visibility especially in the automotive and aeronautical context but also for all transportation or surveillance tasks. The chosen wavelength bands are the Short Wave Infrared SWIR and the Long Wave Infrared LWIR band which are less obscured by reduced visibility conditions than the visible band. Furthermore, our field tests clearly show that the two different spectral bands very often contain complementary information. Pyramidal fusion is used to integrate complementary and redundant features of the multi-spectral images into a fused image which can be displayed on a monitor to provide more and better information for the driver or pilot.

  8. γ and fission-reactor radiation effects on the visible-range transparency of aluminum-jacketed, all-silica optical fibers

    Science.gov (United States)

    Griscom, David L.

    1996-08-01

    Four aluminum-jacketed, fluorine-doped silica clad optical fibers with silica core materials fabricated by differing technologies were subjected to sequential 60Co-γ ray and fission-reactor irradiations (at ˜20 and 40 °C, respectively), an intervening isothermal anneal (˜20 °C), and a final isochronal anneal (to 600 °C) while monitoring the radiation-induced absorption spectra in the range ˜400-1000 nm. The two low-OH/low-chloride core fibers (one of which was doped with 0.5 mass % fluorine) both developed bands at 660 and 760 nm which exceeded 10 000 dB/km for doses in the range ˜102-106 Gy(Si); however, these bands declined to irradiation phase [12 MGy(Si) at 5.6 Gy(Si)/s]. All fibers displayed an ``UV band tail,'' which was the strongest in the high-chloride core fiber, as well as bands in the range ˜600-630 nm generally attributed to nonbridging-oxygen hole centers (NBOHCs). During the γ-irradiation phase the strengths of the NBOHC bands proved to be strongly dependent on the method of core material manufacture. Contrary to previous results for acrylate-jacketed fibers, no substantial bleaching of the UV-tail or NBOHC bands took place during γ irradiation despite the continuous propagation of white light powers ˜5-50 μW. The incremental induced absorption spectra consequent to the reactor-irradiation [˜4 MGy(Si) γ-ray dose at 70 Gy(Si)/s, plus a fluence of ≳2.8-MeV neutrons ˜2×1016 cm-2] were much less sensitive to fiber core material. The prospects for developing rad hard optical fibers for fusion reactor diagnostics are discussed in light of these findings.

  9. SINGLE-BAND, TRIPLE-BAND, OR MULTIPLE-BAND HUBBARD MODELS

    NARCIS (Netherlands)

    ESKES, H; SAWATZKY, GA

    1991-01-01

    The relevance of different models, such as the one-band t-J model and the three-band Emery model, as a realistic description of the electronic structure of high-T(c) materials is discussed. Starting from a multiband approach using cluster calculations and an impurity approach, the following

  10. Band-notched ultrawide band antenna loaded with ferrite slab

    Science.gov (United States)

    Wang, Hao; Zong, Weihua; Sun, Nian X.; Lin, Hwaider; Li, Shandong

    2017-05-01

    In this paper, a novel technique to design a band-notched UWB antenna by using Yttrium Iron Garnet (YIG) ferrite is proposed. A printed slot UWB antenna with size of 21mm×26 mm×0.8 mm is adopted as a basic antenna. A piece of ferrite slab with size of 5 mm×10 mm×2 mm is attached on the feeding layer of the antenna to achieve band-notched characteristics. The measured -10 dB bandwidth of the antenna without ferrite slab is 2.91-10.98 GHz. With loading of ferrite slab, the bandwidth turns to 2.73-5.12 and 5.87-10.78 GHz. A band notch of 5.12- 5.87 GHz is achieved to filter WLAN 5 GHz (5.15-5.825 GHz) band. The proposed technique has virtue of easy fabrication and keeping antenna miniaturization.

  11. Band-to-Band Tunneling Transistors: Scalability and Circuit Performance

    Science.gov (United States)

    2013-05-01

    55* MEDICI ...3.2.1 Tunneling Theory 3.3 Simulation Methods 3.3.1 MEDICI 3.3.2 Sentaurus Local Tunneling 3.3.3 Sentaurus Nonlocal Tunneling 3.4 Sentaurus...tunneling current. 3.3.1 MEDICI MEDICI is a one and two-dimensional simulator created by Synopsys, Inc. [18]. It contains a band-to-band

  12. 47 CFR 15.245 - Operation within the bands 902-928 MHz, 2435-2465 MHz, 5785-5815 MHz, 10500-10550 MHz, and 24075...

    Science.gov (United States)

    2010-10-01

    ... limited to intentional radiators used as field disturbance sensors, excluding perimeter protection systems. (b) The field strength of emissions from intentional radiators operated within these frequency bands shall comply with the following: Fundamental frequency (MHz) Field strength of fundamental (millivolts...

  13. Radiation protection

    International Nuclear Information System (INIS)

    Koelzer, W.

    1975-01-01

    Physical and radiological terms, quantities, and units. Basic principles of radiation protection (ICRP, IAEA, EURATOM, FRG). Biological effects of ionizing radiation. Objectives of practical radiation protection. (HP) [de

  14. Measurement and Modeling of Particle Radiation in Coal Flames

    DEFF Research Database (Denmark)

    Bäckström, Daniel; Johansson, Robert; Andersson, Klas Jerker

    2014-01-01

    flame. Spectral radiation, total radiative intensity, gas temperature, and gas composition were measured, and the radiative intensity in the furnace was modeled with an axisymmetric cylindrical radiation model using Mie theory for the particle properties and a statistical narrow-band model for the gas...

  15. Intensity formulas for triplet bands

    Science.gov (United States)

    Budo, A.

    1982-01-01

    Previous work in this area is surveyed and the mathematics involved in determining the quantitative intensity measurements in triplet bands is presented. Explicit expressions for the intensity distribution in the branches of the 3 Sigma-3 Pi and 1 Sigma-3Pi bands valid for all values of the coupling constant Y of the 3 Pi terms are given. The intensity distribution calculated according to the formulas given is compared with measurements of PH, 3 Pi-3 Sigma. Good quantitative agreement is obtained.

  16. 47 CFR 90.279 - Power limitations applicable to the 421-430 MHz band.

    Science.gov (United States)

    2010-10-01

    ... the 421-430 MHz band will be subject to Effective Radiated Power (ERP) and Effective Antenna Height (EAH) limitations as shown in the table below. ERP is defined as the product of the power supplied to... height above mean sea level. Limits of Effective Radiated Power (ERP) Corresponding to Effective Antenna...

  17. Excited ionic and neutral fragments produced by dissociation of the N2(+)-asterisk H band

    Science.gov (United States)

    Samson, James A. R.; Chung, Y.; Lee, E.-M.

    1991-01-01

    Atomic fluorescence produced by dissociative photoionization of N2 was observed and identified in experiments where fluorescent radiation was produced by irradiating N2 gas with undispersed synchrotron radiation. The spectrum was detected with a multichannel plate electron multiplier. Evidence is presented that the H band of N2(+)-asterisk does predissociate into excited neutral and ionic atoms.

  18. Design and realization of a planar ultrawideband antenna with notch band at 3.5 GHz.

    Science.gov (United States)

    Azim, Rezaul; Islam, Mohammad Tariqul; Misran, Norbahiah; Yatim, Baharudin; Arshad, Haslina

    2014-01-01

    A small antenna with single notch band at 3.5 GHz is designed for ultrawideband (UWB) communication applications. The fabricated antenna comprises a radiating monopole element and a perfectly conducting ground plane with a wide slot. To achieve a notch band at 3.5 GHz, a parasitic element has been inserted in the same plane of the substrate along with the radiating patch. Experimental results shows that, by properly adjusting the position of the parasitic element, the designed antenna can achieve an ultrawide operating band of 3.04 to 11 GHz with a notched band operating at 3.31-3.84 GHz. Moreover, the proposed antenna achieved a good gain except at the notched band and exhibits symmetric radiation patterns throughout the operating band. The prototype of the proposed antenna possesses a very compact size and uses simple structures to attain the stop band characteristic with an aim to lessen the interference between UWB and worldwide interoperability for microwave access (WiMAX) band.

  19. Dual Band Notched EBG Structure based UWB MIMO/Diversity Antenna with Reduced Wide Band Electromagnetic Coupling

    Science.gov (United States)

    Jaglan, Naveen; Kanaujia, Binod Kumar; Gupta, Samir Dev; Srivastava, Shweta

    2017-10-01

    A dual band-notched MIMO/Diversity antenna is proposed in this paper. The proposed antenna ensures notches in WiMAX band (3.3-3.6 GHz) besides WLAN band (5-6 GHz). Mushroom Electromagnetic Band Gap (EBG) arrangements are employed for discarding interfering frequencies. The procedure followed to attain notches is antenna shape independent with established formulas. The electromagnetic coupling among two narrowly set apart Ultra-Wide Band (UWB) monopoles is reduced by means of decoupling bands and slotted ground plane. Monopoles are 90° angularly parted with steps on the radiator. This aids to diminish mutual coupling and also adds in the direction of impedance matching by long current route. S21 or else mutual coupling of fewer than 15 dB is established over antenna operating range. Two-port envelope correlation coefficient is lower than 0.02 in UWB range of 3.1 GHz-10.6 GHz. The shifting in notch frequencies by varying variables in formulas is also reported. The suggested antenna is designed on low budget FR-4 substrate with measurements as (58 × 45 × 1.6) mm3. Simulated and measured results of fabricated antenna are found to be in close agreement.

  20. A Novel Hammer-Shaped UWB Antenna with Triple Notched-Band for Rejecting RLS, WLAN and XSCS bands

    Directory of Open Access Journals (Sweden)

    H. S. Mewara

    2017-10-01

    Full Text Available A novel hammer-shaped UWB printed antenna with triple notched stop bands is presented and fabricated on FR-4 substrate with size of 40×40×1.6 mm3. The proposed antenna is composed of hammer-shaped patch with C-shaped slot, U-shaped slot on feed line, and inverted stepped notch and bevel edges with pair of L-shaped slots in partial ground plane. The fabricated antenna is tested and obtained impedance bandwidth 2.89 ̶ 11.6 GHz with three notched stop bands 3.15 ̶ 3.7 GHz, 5.45 ̶ 6.8 GHz, and 7.5 ̶  8.8 GHz, for radiolocation system (RLS, wireless local area networks (WLAN, and X-band satellite communication system (XSCS bands, respectively. Moreover, the antenna result shows omnidirectional radiation pattern, average gain of 3.10 dBi over the whole UWB band except at the notched frequency bands.

  1. A 3D printed dual GSM band near isotropic on-package antenna

    KAUST Repository

    Zhen, Su

    2017-10-25

    In this paper, we propose an on-package dual band monopole antenna with near-isotropic radiation pattern for GSM mobile applications. The proposed antenna is well matched for both GSM 900 and 1800 bands and provides decent gain for both the bands (1.67 and 3.27 dBi at 900 MHz and 1800 MHz respectively). The antenna is printed with silver ink on a 3D printed polymer based package. The package houses the GSM electronics and the battery. By optimizing the antenna arms width and length, a near-isotropic radiation pattern is achieved. Unlike the published isotropic antennas which are either single band or large in size, the proposed antenna covers both GSM bands with required bandwidth and is only half wavelength long. The design is low cost and highly suitable for various GSM applications such as localization, in additional to conventional communication applications.

  2. Radiation enteritis

    Science.gov (United States)

    Radiation enteropathy; Radiation-induced small bowel injury; Post-radiation enteritis ... Radiation therapy uses high-powered x-rays, particles, or radioactive seeds to kill cancer cells. The therapy ...

  3. Radiation biology

    International Nuclear Information System (INIS)

    Neumeister, K.

    1977-01-01

    This chapter is included in a textbook which is primarily intended for medical students. The following topics are dealt with: radiation effects on molecules; chemical and biochemical radiation effects; modification of radiation effects and radiosensitivity; radiation-induced pathomorphological and pathophysiological effects in organs and organ systems; radiation syndrome; radiation effects in embryos and fetuses; genetic radiation effects; carcinogenesis and leukemogenesis after irradiation; and radiation effects after intake of radionuclides

  4. Ring with changeable radiation dosimeter

    International Nuclear Information System (INIS)

    Collica, C.; Epifano, L.; Farella, R.

    1976-01-01

    A ring for housing a disc of radiation measuring material is described comprising a band having a circular shape and a housing integral with the band. The housing comprises a hollow cylindrical section substantially normal to the band surface and terminating in an inwardly disposed annular flange which defines a substantially circular aperture. In a preferred embodiment of the invention a retaining protrusion formed on the inside of the cylindrical section and spaced from the annular flange is provided to retain a plurality of discs mounted in the housing in layered fashion

  5. Polygonal deformation bands in sandstone

    Science.gov (United States)

    Antonellini, Marco; Nella Mollema, Pauline

    2017-04-01

    We report for the first time the occurrence of polygonal faults in sandstone, which is compelling given that layer-bound polygonal fault systems have been observed so far only in fine-grained sediments such as clay and chalk. The polygonal faults are dm-wide zones of shear deformation bands that developed under shallow burial conditions in the lower portion of the Jurassic Entrada Fm (Utah, USA). The edges of the polygons are 1 to 5 meters long. The shear deformation bands are organized as conjugate faults along each edge of the polygon and form characteristic horst-like structures. The individual deformation bands have slip magnitudes ranging from a few mm to 1.5 cm; the cumulative average slip magnitude in a zone is up to 10 cm. The deformation bands heaves, in aggregate form, accommodate a small isotropic horizontal extension (strain Crosscutting relationships are rare. The interactions of the deformation bands are similar to those of mode I opening fractures. Density inversion, that takes place where under-compacted and over-pressurized layers (Carmel Fm) lay below normally compacted sediments (Entrada Sandstone), may be an important process for polygonal deformation bands formation. The gravitational sliding and soft sediment structures typically observed within the Carmel Fm support this hypothesis. Soft sediment deformation may induce polygonal faulting in the section of the Entrada Sandstone just above the Carmel Fm. The permeability of the polygonal deformation bands is approximately 10-14 to 10-13 m2, which is less than the permeability of the host, Entrada Sandstone (range 10-12 to 10-11 m2). The documented fault networks have important implications for evaluating the geometry of km-scale polygonal fault systems in the subsurface, top seal integrity, as well as constraining paleo-tectonic stress regimes.

  6. X-Band CubeSat Communication System Demonstration

    Science.gov (United States)

    Altunc, Serhat; Kegege, Obadiah; Bundick, Steve; Shaw, Harry; Schaire, Scott; Bussey, George; Crum, Gary; Burke, Jacob C.; Palo, Scott; O'Conor, Darren

    2015-01-01

    Today's CubeSats mostly operate their communications at UHF- and S-band frequencies. UHF band is presently crowded, thus downlink communications are at lower data rates due to bandwidth limitations and are unreliable due to interference. This research presents an end-to-end robust, innovative, compact, efficient and low cost S-band uplink and X-band downlink CubeSat communication system demonstration between a balloon and a Near Earth Network (NEN) ground system. Since communication systems serve as umbilical cords for space missions, demonstration of this X-band communication system is critical for successfully supporting current and future CubeSat communication needs. This research has three main objectives. The first objective is to design, simulate, and test a CubeSat S- and X-band communication system. Satellite Tool Kit (STK) dynamic link budget calculations and HFSS Simulations and modeling results have been used to trade the merit of various designs for small satellite applications. S- and X-band antennas have been tested in the compact antenna test range at Goddard Space Flight Center (GSFC) to gather radiation pattern data. The second objective is simulate and test a CubeSat compatible X-band communication system at 12.5Mbps including S-band antennas, X-band antennas, Laboratory for Atmospheric and Space Physics (LASP) /GSFC transmitter and an S-band receiver from TRL-5 to TRL-8 by the end of this effort. Different X-band communication system components (antennas, diplexers, etc.) from GSFC, other NASA centers, universities, and private companies have been investigated and traded, and a complete component list for the communication system baseline has been developed by performing analytical and numerical analysis. This objective also includes running simulations and performing trades between different X-band antenna systems to optimize communication system performance. The final objective is to perform an end-to-end X-band CubeSat communication system

  7. William Band at Yenching University

    Science.gov (United States)

    Hu, Danian

    2008-04-01

    William Band (1906-1993) has been widely remembered by his American colleagues and students as ``a fine physicist and teacher,'' who taught at Washington State University in Pullman between 1949 and 1971 and authored Introduction to Quantum Statistics (1954) and Introduction to Mathematical Physics (1959). Not many, however, knew much about Band's early career, which was very ``uncommon and eventful.'' Born in England, Band graduated from University of Liverpool in 1927 with an MsSc degree in physics. Instead of pursuing his Ph.D. at Cambridge, he chose to teach physics at Yenching University, a prestigious Christian university in Beijing, China. Arriving in 1929, Band established his career at Yenching, where he taught and researched the theory of relativity and quantum mechanics, pioneered the study on low-temperature superconductivity in China, founded the country's first graduate program in physics, and chaired the Physics Department for 10 years until he fled from Yenching upon hearing of the attack on Pearl Harbor. It took him two years to cross Japanese occupied areas under the escort of the Communist force; he left China in early 1945. This presentation will explore Band's motivation to work in China and his contributions to the Chinese physics research and education.

  8. Whistler Triggered Upper Band Chorus Observed in Alaska

    Science.gov (United States)

    Hosseini, P.; Golkowski, M.

    2017-12-01

    VLF radiation from lightning discharges is one of several sources of energy injection into the inner magnetosphere from the Earth. Lightning discharges initially produce a broadband impulse or `sferic' but after propagation in the dispersive magnetosphere this waveform soon becomes quasi narrow band with the characteristic spectrographic form of the whistler. Most of the lightning induced VLF wave energy injected into the magnetosphere will be unducted with a k-vector which becomes increasingly oblique. Although unducted radiation is ubiquitous throughout the inner magnetosphere, it is generally of a low amplitude due to Landau damping and is not expected to produce strong nonlinear phenomena such as triggered emissions and chorus waves. However, VLF wave energy ducted or trapped in field-aligned plasma density enhancements can have relatively large amplitudes due to focusing and also linear cyclotron resonance growth. Therefore high amplitude ducted whistler waves can trigger a number of complex nonlinear phenomena. These include the triggering of VLF emissions and triggering of VLF hiss or chorus. Such phenomena are generally considered to result from nonlinear electron cyclotron phase trapping. Observation of such VLF emissions triggered by natural whistlers have been reported since the 1970s in Antarctica. We present observations of whistlers triggered upper band chorus emission from Alaska. Dispersion analyze of whistlers determine the L-shell range to be 4.5 clear frequency band gap between upper and lower band of the observed chorus emissions. The observations point to ducted chorus generation in the vicinity of the plasmapause boundary.

  9. Photoionization bands of rubidium molecule

    Science.gov (United States)

    Rakić, M.; Pichler, G.

    2018-03-01

    We studied the absorption spectrum of dense rubidium vapor generated in a T-type sapphire cell with a special emphasis on the structured photoionization continuum observed in the 200-300 nm spectral region. The photoionization spectrum has a continuous atomic contribution with a pronounced Seaton-Cooper minimum at about 250 nm and a molecular photoionization contribution with many broad bands. We discuss the possible origin of the photoionization bands as stemming from the absorption from the ground state of the Rb2 molecule to excited states of Rb2+* and to doubly excited autoionizing states of Rb2** molecule. All these photoionization bands are located above the Rb+ and Rb2+ ionization limits.

  10. Band-in-band segregation of multidisperse granular mixtures

    NARCIS (Netherlands)

    Newey, M.; Ozik, J.; van der Meer, S.M.

    2004-01-01

    Radial and axial segregation is investigated experimentally in polydisperse mixtures of granular materials rotated in a long, partly filled, horizontal cylinder. Radial segregation by size is observed in all polydisperse mixtures. Axial segregation, with smaller-size particles forming bands within

  11. Time-dependent effect of rutin on skin fibroblasts membrane disruption following UV radiation

    Directory of Open Access Journals (Sweden)

    Agnieszka Gęgotek

    2017-08-01

    In conclusion, highest skin fibroblasts membrane level of rutin occurred in 2–4 h following UVA/B-radiation results in its strongest effect on biomembrane structure and functions and cellular antioxidant system irrespective of the radiation type.

  12. Response of avocado genotypes to improvement through 60Co gamma radiation

    International Nuclear Information System (INIS)

    Cruz, E. De la; Rubi A, M.; Garcia A, J.M.

    1997-01-01

    Ten avocado genotypes were subjected to gamma radiation from 0 to 45 Gy in 1993. Vegetative and reproductive data were analysed in a factorial design. Genotypes differed significative on height and fruit number. Radiation affected significative fruit number but not tree height. ''Hass'' showed strongest interaction between genotype and doses, for fruit number. (Author)

  13. Compact Tri-Band Notched Characteristics UWB Antenna for WiMAX, WLAN and X-Band Applications

    Directory of Open Access Journals (Sweden)

    E. K. I. Hamad

    2017-05-01

    Full Text Available Compact microstrip-fed printed monopole antenna with triple band-notched characteristics is suggested for ultra-wideband (UWB applications. The antenna is constructed of a conventional rectangular microstrip patch antenna with partial ground plane and T-shaped strip employed in the ground plane as well as an inverted Ω- and L-shaped slots incorporated within the radiated element. The notched functions are created by the inverted Ω- and L-shaped slots, which are realized for WiMAX (from 2.69 to 4.5 GHz and WLAN (from 5.49 to 6.37 GHz. The T-shaped parasitic strip generates the third notch for the X-band uplink satellite communication (from 8.15 to 9.61 GHz. The measured operating -10 dB bandwidth of the proposed antenna extends from 2.39 to more than 18 GHz except at the notched bands. The prototype antenna has a total area of 20×20×1.6 mm3. Electromagnetic (EM simulations are carried out using 3D full-wave FEM-based simulator. EM simulation results are in good agreement with measurement results. The radiation pattern of the proposed antenna is nearly Omni-directional over the whole targeted band.

  14. Radiology of vertical banded gastroplasty

    International Nuclear Information System (INIS)

    Leekam, R.N.; Deitel, M.; Shankar, L.; Salsberg, B.

    1987-01-01

    Vertical banded gastroplasty is now the most common procedure for the surgical treatment of obesity. In the past 4 years 120 patients have been referred for radiologic examination. This exhibit describes the normal and abnormal findings in many of these patients. The authors divided radiologic abnormalities into three groups: abnormalities of the partition, abnormalities of the banded channel, and ulcers and extragastric leaks. The authors' examination technique has been adapted from those described by others, our important addition being the preliminary precontrast film, on which the staple lines can be examined. This has proved most effective in the detection of partition defects

  15. Estimate of reddening for T Pyx based on optical diffuse interstellar bands (DIBs)

    Science.gov (United States)

    Shore, S. N.; Augusteijn, T.; Ederoclite, A.; Uthas, H.

    2011-04-01

    We report the first results for the latest outburst of the recurrent nova T Pyx from the FIES echelle spectrograph on the 2.6 m Nordic Optical Telescope (NOT) at La Palma from 3700-7200 A with a resolution of 67000. The first spectrum, obtained on 2011 Apr. 15.92 UT during the rise to maximum (V approx 9.5) with integration time of 600 sec with a S/N of 30 at 6000 A (continuum), was sufficiently well exposed to display some of the strongest optical diffuse interstellar bands (DIBs).

  16. Compact filtering monopole patch antenna with dual-band rejection.

    Science.gov (United States)

    Kim, Sun-Woong; Choi, Dong-You

    2016-01-01

    In this paper, a compact ultra-wideband patch antenna with dual-band rejection is proposed. The proposed antenna filters 3.3-3.8 GHz WiMAX and 5.15-5.85 GHz WLAN by respectively rejecting these bands through a C-shaped slit and a λg/4 resonator. The λg/4 resonator is positioned as a pair, centered around the microstrip line, and a C-type slit is inserted into an elliptical patch. The impedance bandwidth of the proposed antenna is 2.9-9.3 GHz, which satisfies the bandwidth for ultra-wideband communication systems. Further, the proposed antenna provides dual-band rejection at two bands: 3.2-3.85 and 4.7-6.03 GHz. The radiation pattern of the antenna is omnidirectional, and antenna gain is maintained constantly while showing -8.4 and -1.5 dBi at the two rejected bands, respectively.

  17. Multislot microstrip antenna for ultra-wide band applications

    Directory of Open Access Journals (Sweden)

    Noor M. Awad

    2018-01-01

    Full Text Available In this paper designs of both planar ultra-wide band (UWB antenna and UWB antenna with two rejected bands are given. The antenna consists of a rectangular patch etched on FR4-substrate with 50 Ω feed line. The rectangular patch has one round cut at each corner with one slot in the ground plane. The simulated bandwidth with return loss (RL ⩾ 10 dB is 3.42–11.7 GHz. The rejected bands are the WLAN and X-bands, achieved by inserting slots in the patch and the feed. The simulated results of the proposed antenna indicate higher gain at the passbands while a sharp drop at the rejected bands is seen. The radiation pattern is of dipole shape in the E-plane and almost omnidirectional in the H-plane. The high frequency structure simulator (HFSS is used to design and simulate the antennas behavior over the different frequency ranges. Measurements confirm the antenna characteristic as predicted in the simulation with a slight shift in frequencies.

  18. Design and analysis of X-band femtosecond linac

    Energy Technology Data Exchange (ETDEWEB)

    Uesaka, M.; Kozawa, T.; Takeshita, A.; Kobayashi, T.; Ueda, T.; Miya, K. [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.

    1997-03-01

    Femtosecond quantum phenomena research project is proposed at Nuclear Engineering Research Laboratory, University of Tokyo. The research facility consists of an X-band (11.424GHz) femtosecond electron linac, a femtosecond wavelength tunable laser, two S-band (2.856GHz) picosecond electron linacs and measuring equipments. Especially, we aim to generate a 100 fs (FWHM) electron single bunch with more than 1 nC at the X-band femtosecond linac. Ultrafast processes in radiation physics, chemistry, material science and microscopic electromagnetic phenomena are going to be analyzed there. Here the design and analysis of an X-band femtosecond linac is presented. The simulation of electron dynamics is carried out including magnetic pulse compression by using PARMELA and SUPERFISH. It is found by the simulation that the 600 ps (tail-to-tail) electron emission from a 200 kV thermionic gun can be bunched and compressed to 110 fs (FWHM) with the charge of 0.8 nC which gives 7.3 kA. We plan to use one high power X-band klystron which can supply 60 MW with more than 200 ns pulse duration. The flatness of plateau of the pulse should be 0.2% for stable ultrashort bunch generation. (author)

  19. A Minimized MIMO-UWB Antenna with High Isolation and Triple Band-Notched Functions

    Science.gov (United States)

    Kong, Yuanyuan; Li, Yingsong; Yu, Kai

    2016-11-01

    A compact high isolation MIMO-UWB antenna with triple frequency rejection bands is proposed for UWB communication applications. The proposed MIMO-UWB antenna consists of two identical UWB antennas and each antenna element has a semicircle ring shaped radiation patch fed by a bend microstrip feeding line for covering the UWB band, which operates from 2.85 GHz to 11.79 GHz with an impedance bandwidth of 122.1 %. By etching a L-shaped slot on the ground plane, and embedding an "anchor" shaped stub into the patch and integrating an open ring under the semicircle shaped radiation patch, three notch bands are realized to suppress WiMAX (3.3-3.6 GHz), WLAN(5.725-5.825 GHz) and uplink of X-band satellite (7.9-8.4 GHz) signals. The high isolation with S21UWB band is obtained by adding a protruded decoupling structure. The design procedure of the MIMO-UWB antenna is given in detail. The proposed MIMO-UWB antenna is simulated, fabricated and measured. Experimental results demonstrate that the proposed MIMO-UWB antenna has a stable gain, good impedance match, high isolation, low envelope correlation coefficient and good radiation pattern at the UWB operating band and it can provide three designated notch bands.

  20. Compact Bioimplantable MICS and ISM Band Antenna Design for Wireless Biotelemetry Applications

    Directory of Open Access Journals (Sweden)

    M. Palandoken

    2017-12-01

    Full Text Available A compact dual-band bioimplantable antenna with novel resonator geometry is designed for dual-band wireless biotelemetry applications in MICS and ISM bands. The radiating element geometry is based on an L-shaped transmission line fed anti-spiral resonator structure, which is loaded with the spiral resonator at the end to increase the effective electrical length. The effect of resonator geometric parameters on the return loss is discussed with the inclusion of three layered lossy human model in the numerical calculations. The footprint size of the optimized bioimplantable antenna is 15 x 15 x 1.92 mm^3, having the total surface area of λ0/20 x λ0/20, where λ0 is the free space wavelength at 403 MHz in MICS band. The compact dual-band antenna has the impedance bandwidth of 24.81% at 403 MHz and 14.7% at 2.45 GHz with the gain values -12.25dBi and -12.4 dBi in MICS and ISM bands, respectively. The average SAR values at the resonance frequencies are numerically computed to find out the input power delivered to the antenna for the reliable operation. The radiation parameters and 3D radiation patterns indicate the potential use of the proposed implantable antenna with the permissible gain in dual-band wireless biotelemetry applications.

  1. Combination Bands of the Nonpolar OCS Dimer Involving Intermolecular Modes

    Science.gov (United States)

    Rezaei, M.; Oliaee, J. Norooz; Moazzen-Ahmadi, N.; McKellar, A. R. W.

    2012-06-01

    Spectra of the nonpolar carbonyl sulfide in the region of the OCS ν_1 fundamental band were observed in a supersonic slit-jet apparatus. The expansion gas was probed using radiation from a tunable diode laser employed in a rapid-scan signal averaging mode. Three bands centered at 2085.906, 2103.504, and 2114.979 cm-1 were observed and anlysed. The rotational assignment and fitting of the bands were made by fixing the lower state parameters to those for the ground state of nonpolar (OCS)_2, thus confirming that they were indeed combination bands of the of the most stable isomer of OCS dimer. The band centered at 2085.906 cm-1 is a combination of the forbidden A_g intramolecular mode plus the geared bend intermolecular mode and that centered at 2114.979 cm-1 is a combination of the allowed B_u intramolecular mode plus the intermolecular van der Waals stretch. The combination at 2103.504 cm-1 can be assigned as a band whose upper state involves four quanta of the intramolecular bend or the B_u intramolecular mode plus two quanta of the intermolecular torsional mode. Isotopic work is needed to conclusively identify the vibrational assignment of this band. Our experimental frequencies for the geared bend and van der Waals modes are in good agreement with a recent high level ab initio calculation by Brown et al. J. Brown, Xiao-Gang Wang, T. Carrington Jr. and Richard Dawes, Journal of Chemical Physics, submitted.

  2. Correlations in a band insulator

    Czech Academy of Sciences Publication Activity Database

    Sentef, M.; Kuneš, Jan; Werner, P.; Kampf, A. P.

    2009-01-01

    Roč. 80, č. 15 (2009), 155116/1-155116/7 ISSN 1098-0121 Institutional research plan: CEZ:AV0Z10100521 Keywords : electronic correlations * dynamical mean-field theory * band insulator Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.475, year: 2009

  3. Metaphyseal bands in osteogenesis imperfecta

    Directory of Open Access Journals (Sweden)

    Suresh S

    2010-01-01

    Full Text Available An increasing number of patients with osteogenesis imperfecta are undergoing pamidronate therapy to prevent the incidence of fragility fractures. The authors herein report a child aged 3 years who received five cycles of pamidronate, resulting in metaphyseal bands, known as "zebra lines."

  4. Singing in the Band Rehearsal.

    Science.gov (United States)

    Wolbers, Mark

    2002-01-01

    Explains how singing can be incorporated into the band rehearsal. Discusses how to improve student aural skills by including singing in the rehearsal and the benefits of having students sing. Describes how music teachers can use songs or chorales in the classroom. (CMK)

  5. Radiative cooling in the nocturnal boundary layer

    NARCIS (Netherlands)

    Tjemkes, S.A.

    1988-01-01

    In this thesis the transfer of infrared radiation (electromagnetic waves with a wavelength between 3.6 and 100 μm) through a cloudfree nocturnal boundary layer is studied. To simulate the transfer of infrared radiation an accurate narrow band model which simulates the absorption and

  6. Synthesis and design of waveguide band-stop filters without out-of-band spurious responses for plasma diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Montejo-Garai, Jose R., E-mail: jr@etc.upm.es [Departamento de Electromagnetismo y Teoria de Circuitos, Universidad Politecnica de Madrid, Ciudad Universitaria s/n, Madrid 20840 (Spain); Leal-Sevillano, Carlos A. [Departamento de Electromagnetismo y Teoria de Circuitos, Universidad Politecnica de Madrid, Ciudad Universitaria s/n, Madrid 20840 (Spain); Ruiz-Cruz, Jorge A. [Escuela Politecnica Superior, Universidad Autonoma de Madrid, C/Fco. Tomas y Valiente 11, Madrid 28409 (Spain); Rebollar, Jesus M. [Departamento de Electromagnetismo y Teoria de Circuitos, Universidad Politecnica de Madrid, Ciudad Universitaria s/n, Madrid 20840 (Spain); Estrada, Teresa [T. Laboratorio Nacional de Fusion, Asociacion Euratom-CIEMAT, Madrid 28040 (Spain)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer A rigorous systematic design process based on circuit synthesis is proposed for band-stop filters. Black-Right-Pointing-Pointer The new compact E-plane waveguide structure reduces drastically the unwanted resonances in a very large pass band. Black-Right-Pointing-Pointer The manufacturing process together with the computation effort is significantly reduced. Black-Right-Pointing-Pointer Experimental results validate the state-of-art electrical responses. - Abstract: Band-stop or notch filters play a crucial role in plasma diagnosis systems to protect receivers from the stray radiation. In this work, a rigorous design process based on circuit synthesis in addition to an extremely compact E-plane waveguide structure is proposed for this kind of filters. On the one hand, the transfer function verifying the rejection specification is analytically obtained, fixing the minimum number of required cavities. On the other hand, a coupling structure that reduces drastically the unwanted resonances in filters with a very large pass band requirement, is presented. This coupling between the rejection cavities and the main rectangular waveguide has additional advantages; (a) unlike typical inductive irises, large coupling coefficients can be implemented (b) a pure E-plane configuration is achieved, which simplifies the manufacturing and also reduces significantly the computational effort. Experimental validation is demonstrated by two pseudo-elliptic fifth-order band-stop filters fabricated and measured in Ka and V bands. In both cases, the filters are free of spurious resonances in their total operation bands.

  7. Broad Band sensors calibration by a GTEM cell

    International Nuclear Information System (INIS)

    Licitra, G.; Francia, F.; Pocai, M.

    1996-01-01

    Increasing interest of public for non ionizing radiation hazard and local authorities surveillance necessity demand for easy to use, reliable measurement instrumentation. Triaxial sensors, with their inherent large frequency response, are excellent candidates to reduce in field difficulties related to narrow band tools utilization, as antennas connected to spectrum analyzer. GTEM cell is a relatively novel tool in EMC field, the use of which seems overcome some limitations of standard TEM cells and antennas. The continues improvement in theory of operation and manufacturing broadens its field of application from canonical electromagnetic compatibility radiated immunity and radiated emission tests. The large operation frequency range (from DC to some GHz) and the compact design, well suited to laboratory use, offers the opportunity of conduct fast tests at a convenient location. (author)

  8. Passive-solar directional-radiating cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Hull, John R. (Hinsdale, IL); Schertz, William W. (Batavia, IL)

    1986-01-01

    A radiative cooling system for use with an ice-making system having a radiating surface aimed at the sky for radiating energy at one or more wavelength bands for which the atmosphere is transparent and a cover thermally isolated from the radiating surface and transparent at least to the selected wavelength or wavelengths, the thermal isolation reducing the formation of condensation on the radiating surface and/or cover and permitting the radiation to continue when the radiating surface is below the dewpoint of the atmosphere, and a housing supporting the radiating surface, cover and heat transfer means to an ice storage reservoir.

  9. Radiation monitor

    International Nuclear Information System (INIS)

    Pao, C.T.; Green, W.K.

    1978-01-01

    A system for indicating radiation from a radioactive fluid such as a gas wherein simultaneous indications of the activity concentration of radioactivity of the gas, the radiation dose rate and average energy of the radiation are provided

  10. Radiation protection

    International Nuclear Information System (INIS)

    Ures Pantazi, M.

    1994-01-01

    This work define procedures and controls about ionizing radiations. Between some definitions it found the following topics: radiation dose, risk, biological effects, international radioprotection bodies, workers exposure, accidental exposure, emergencies and radiation protection

  11. Type testing of a head band dosemeter for measuring eye lens dose in terms of H(P)(3).

    Science.gov (United States)

    Gilvin, P J; Baker, S T; Gibbens, N J; Roberts, G H; Tanner, R J; Eakins, J S; Hager, L G; Daniels, T J

    2013-12-01

    A new head band dosemeter, for the measurement of eye lens dose in terms of Hp(3), has been type tested by Public Health England's Centre for Radiation, Environmental and Chemical Hazards [formerly part of the UK Health Protection Agency (HPA)]. The type tests were based on the International Standard ISO 12794, drawing also upon earlier work at HPA. The results show that, unlike many existing dosemeters, the new head band dosemeter correctly measures Hp(3) for beta radiations as well as photons.

  12. Ionizing radiation

    International Nuclear Information System (INIS)

    Kruger, J.

    1989-01-01

    Ionizing radiation results in biological damage that differs from other hazardous substances and is highly dangerous to man. Ionizing radiation cannot be perceived by man's sense organs and the biological damage cannot be detected immediately afterwards (except in very high doses). Every human being is exposed to low doses of radiation. The structure of the atom; sources of ionizing radiation; radiation units; biological effects; norms for radiation protection; and the national control in South Africa are discussed. 1 fig., 5 refs

  13. Radiation dosimetry

    CERN Document Server

    Hine, Gerald J; Hine, Gerald J

    1956-01-01

    Radiation Dosimetry focuses on the advancements, processes, technologies, techniques, and principles involved in radiation dosimetry, including counters and calibration and standardization techniques. The selection first offers information on radiation units and the theory of ionization dosimetry and interaction of radiation with matter. Topics include quantities derivable from roentgens, determination of dose in roentgens, ionization dosimetry of high-energy photons and corpuscular radiations, and heavy charged particles. The text then examines the biological and medical effects of radiation,

  14. 47 CFR 15.242 - Operation in the bands 174-216 MHz and 470-668 MHz.

    Science.gov (United States)

    2010-10-01

    ... bands 174-216 MHz and 470-668 MHz. (a) The marketing and operation of intentional radiators under the...) This authority to operate does not extend to mobile vehicles, such as ambulances, even if those... mobile stations operating under part 90 of this chapter in the 470-512 MHz band, and radio astronomy...

  15. Fully inkjet printed wide band cantor fractal antenna for RF energy harvesting application

    KAUST Repository

    Bakytbekov, Azamat

    2017-06-07

    Energy harvesting from ambient RF signals is feasible, particularly from the GSM bands such as 900MHz, 1800MHz and the 3G band at 2.1GHz. This requires a wideband receive antenna which can cover all these bands with decent gain performance and an omnidirectional radiation pattern. In this work, a novel Cantor fractal antenna has been designed which fulfills the above mentioned performance requirements. Antenna has been realized through a combination of 3D inkjet printing of plastic substrate and 2D inkjet printing of metallic nanoparticles based ink. The stable impedance and radiation performance of the antenna over a bandwidth of 0.8GHz to 2.2GHz (93 %) shows the feasibility of its employment in wide band energy harvesting applications.

  16. Linear methods in band theory

    DEFF Research Database (Denmark)

    Andersen, O. Krogh

    1975-01-01

    Two approximate methods for solving the band-structure problem in an efficient and physically transparent way are presented and discussed in detail. The variational principle for the one-electron Hamiltonian is used in both schemes, and the trial functions are linear combinations of energy......-independent augmented plane waves (APW) and muffin-tin orbitals (MTO), respectively. The secular equations are therefore eigenvalue equations, linear in energy. The trial functions are defined with respect to a muffin-tin (MT) potential and the energy bands depend on the potential in the spheres through potential...... parameters which describe the energy dependence of the logarithmic derivatives. Inside the spheres, the energy-independent APW is that linear combination of an exact solution, at the arbitrary but fixed energy Eν, and its energy derivative which matches continuously and differentiably onto the plane...

  17. NCenter wide band neutrino beam

    International Nuclear Information System (INIS)

    Stutte, L.G.

    1985-01-01

    This memo describes the physical properties of the currently operating N-Center wide band neutrino beam---commonly called the triplet train, following a past tradition of a triplet lens configuration. In reality, in order to gain a larger momentum acceptance and to minimize the angular divergence of the beam, a quadruplet beam (4 lenses) employing point-to-parallel optics at a central momentum of 300 GeV was built. 6 refs., 13 figs., 1 tab

  18. [Gastric band erosion: Alternative management].

    Science.gov (United States)

    Echaverry-Navarrete, Denis José; Maldonado-Vázquez, Angélica; Cortes-Romano, Pablo; Cabrera-Jardines, Ricardo; Mondragón-Pinzón, Erwin Eduardo; Castillo-González, Federico Armando

    2015-01-01

    Obesity is a public health problem, for which the prevalence has increased worldwide at an alarming rate, affecting 1.7 billion people in the world. To describe the technique employed in incomplete penetration of gastric band where endoscopic management and/or primary closure is not feasible. Laparoscopic removal of gastric band was performed in five patients with incomplete penetrance using Foley catheterization in the perforation site that could lead to the development of a gastro-cutaneous fistula. The cases presented include a leak that required surgical lavage with satisfactory outcome, and one patient developed stenosis 3 years after surgical management, which was resolved endoscopically. In all cases, the penetration site closed spontaneously. Gastric band erosion has been reported in 3.4% of cases. The reason for inserting a catheter is to create a controlled gastro-cutaneous fistula, allowing spontaneous closure. Various techniques have been described: the totally endoscopic, hybrid techniques (endoscopic/laparoscopic) and completely laparoscopic. A technique is described here that is useful and successful in cases where the above-described treatments are not viable. Copyright © 2015. Published by Masson Doyma México S.A.

  19. Multiple Scattering of Terrestrial Snow in X-band and Ku band Radar Remote Sensing

    Science.gov (United States)

    Xu, X.; Tsang, L.; Wenmo, C.; Yueh, S. H.

    2012-12-01

    Terrestrial snow as an important storage of the fresh water plays a key role in the global water cycle. Regional and global snow water equivalence (SWE) distribution has impact on various hydrological, meteorological applications. Using the SAR image at X band and Ku band for remote sensing of SWE is drawing more attention as it can obtain the complete spatial and temporal coverage of snow distribution under nearly all weather conditions. The satellite mission Cold Regions Hydrology High-resolution Observatory, (CoReH2O), is being evaluated by ESA and the Snow and Cold Land process (SCLP) Satellite Mission was recommended for NASA implementation in the Decadal Survey report. The electromagnetic signatures of different snow structures and snow ground interfaces are studied in both X and Ku band. To characterize the electromagnetic properties of snow, we need to establish the detailed snow structure. Recently, we developed a computer generated bi-continuous media to describe the snow structure. The Maxwell equations are directly applied and solved numerically. Then the results are combined with the dense media radiative equations so that full multiple scattering was considered. To systematically study the snow structure influence to the backscattering signal, we generate a look up table for a few typical types of snow status, such as fresh snow, depth hoar etc. The snow-ground interface is considered as rough surface. The backscattering from the surfaces is calculated through the look up table, which is generated by solving full wave simulations of Numerical Maxwell Model in 3 Dimensional (NMM3D) rough surfaces. Both co-polarization and cross-polarization are computed. The combined model is validated through comparison with recent CLPX, SnowSCAT and SnowSAR field measurements.

  20. A Reconfigurable Triple-Notch-Band Antenna Integrated with Defected Microstrip Structure Band-Stop Filter for Ultra-Wideband Cognitive Radio Applications

    Directory of Open Access Journals (Sweden)

    Yingsong Li

    2013-01-01

    Full Text Available A printed reconfigurable ultra-wideband (UWB monopole antenna with triple narrow band-notched characteristics is proposed for cognitive radio applications in this paper. The triple narrow band-notched frequencies are obtained using a defected microstrip structure (DMS band stop filter (BSF embedded in the microstrip feed line and an inverted π-shaped slot etched in the rectangular radiation patch, respectively. Reconfigurable characteristics of the proposed cognitive radio antenna (CRA are achieved by means of four ideal switches integrated on the DMS-BSF and the inverted π-shaped slot. The proposed UWB CRA can work at eight modes by controlling switches ON and OFF. Moreover, impedance bandwidth, design procedures, and radiation patterns are presented for analysis and explanation of this antenna. The designed antenna operates over the frequency band between 3.1 GHz and 14 GHz (bandwidth of 127.5%, with three notched bands from 4.2 GHz to 6.2 GHz (38.5%, 6.6 GHz to 7.0 GHz (6%, and 12.2 GHz to 14 GHz (13.7%. The antenna is successfully simulated, fabricated, and measured. The results show that it has wide impedance bandwidth, multimodes characteristics, stable gain, and omnidirectional radiation patterns.

  1. Realization of an X-Band RF System for LCLS

    CERN Document Server

    McIntosh, Peter; Brooks, William; Emma, Paul; Rago, Carl

    2005-01-01

    A single X-band (11.424 GHz) accelerating structure is to be incorporated in the LCLS Linac design to linearize the energy-time correlation (or gradient) across each bunch, features which originate in the preceding accelerating structures (L0 and L1). This harmonic RF system will operate near the negative RF crest to decelerate the beam, reducing these non-linear components of the correlation, providing a more efficient compression in the downstream bunch compressor chicanes (BC1 and BC2). These non-linear correlation components, if allowed to grow, would lead to Coherent Synchrotron Radiation (CSR) instabilities in the chicanes, effectively destroying the coherence of the photon radiation in the main LCLS undulator. The many years devoted at SLAC in the development of X-band RF components for the NLC/JLC linear collider project, has enabled the technical and financial realization of such an RF system for LCLS. This paper details the requirements for the X-band system and the proposed scheme planned for achie...

  2. Photonic band gap materials: design, synthesis, and applications

    International Nuclear Information System (INIS)

    John, S.

    2000-01-01

    Full text: Unlike semiconductors which facilitate the coherent propagation of electrons, photonic band gap (PBG) materials execute their novel functions through the coherent localization of photons. I review and discuss our recent synthesis of a large scale three-dimensional silicon photonic crystal with a complete photonic band gap near 1.5 microns. When a PBG material is doped with impurity atoms which have an electronic transition that lies within the gap, spontaneous emission of light from the atom is inhibited. Inside the gap, the photon forms a bound state to the atom. Outside the gap, radiative dynamics in the colored vacuum is highly non Markovian. I discuss the influence of these memory effects on laser action. When spontaneous emission is absent, the next order radiative effect (resonance dipole dipole interaction between atoms) must be incorporated leading to anomalous nonlinear optical effects which occur at a much lower threshold than in ordinary vacuum. I describe the collective switching of two-level atoms near a photonic band edge, by external laser field, from a passive state to one exhibiting population inversion. This effect is forbidden in ordinary vacuum. However, in the context of a PBG material, this effect may be utilized for an all-optical transistor. Finally, I discuss the prospects for a phase sensitive, single atom quantum memory device, onto which information may be written by an external laser pulse

  3. More on Estimation of Banded and Banded Toeplitz Covariance Matrices

    OpenAIRE

    Berntsson, Fredrik; Ohlson, Martin

    2017-01-01

    In this paper we consider two different linear covariance structures, e.g., banded and bended Toeplitz, and how to estimate them using different methods, e.g., by minimizing different norms. One way to estimate the parameters in a linear covariance structure is to use tapering, which has been shown to be the solution to a universal least squares problem. We know that tapering not always guarantee the positive definite constraints on the estimated covariance matrix and may not be a suitable me...

  4. Radiation protection

    CERN Multimedia

    CERN. Geneva

    2001-01-01

    This will be a simple explanation of the reasons why CERN has to be careful about radiation protections issues, a practical guide on how to recognize radiation dangers, the monitoring systems that make sure radiation levels are well tolerable norms, and a quick summary of what radiation levels mean in terms of personal risk.

  5. Compact UWB Filtering-Antenna with Controllable WLAN Band Rejection Using Defected Microstrip Structure

    Directory of Open Access Journals (Sweden)

    A. Alhegazi

    2018-04-01

    Full Text Available An ultra-wideband (UWB filtering-antenna with controllable band notch is reported in this paper. The filtering-antenna consists of a modified monopole antenna and defected microstrip structure (DMS. The monopole antenna is modified using microstrip transition in the feedline and block with a triangular-shape slot on each side of the circular patch to produce wider impedance bandwidth with better return loss. The DMS is constructed using U-shaped slot etched on the feedline to provide band notch and remove WLAN band (5.1-5.8 GHz. A switch is employed in the DMS to control the created band notch. The measured results show that the proposed design exhibits a wide impedance bandwidth with controllable WLAN band rejection, realized peak gain of 4.85 dB and omnidirectional radiation pattern. Therefore, the proposed design is suitable for UWB applications.

  6. Dual-band microstrip patch antenna based on metamaterial refractive surface

    Science.gov (United States)

    Salhi, Ridha; Labidi, Mondher; Boujemaa, Mohamed Ali; Choubani, Fethi

    2017-06-01

    In this paper, we present a new design of microstrip patch antenna based on metamaterial refractive surface (MRS). By optimizing the air gap between the MRS layer and the patch antenna to be 7 mm, the band width and the gain of the proposed antenna are significantly enhanced. The proposed prototype presents a dual band antenna. The center frequency for the first band is 2.44 GHz and the generated bandwidth is 25 MHz. The second band has a center frequency of 2.8 GHz and with a bandwidth of 50 MHz. The simulation results are analyzed and discussed in terms of return loss, gain and radiation pattern using electromagnetic simulator software. Finally, the designed dual band antenna is fabricated and different measurement results are performed and compared with simulation results in order to validate its performances. The proposed antenna supports WiBro (wireless broadband), ISM, WiFi, Bluetooth, WiMAX and radars services.

  7. Design and analysis of coplanar waveguide triple-band antenna based on defected ground structure

    Science.gov (United States)

    Lv, Hong; Chen, Wanli; Xia, Xinsheng; Qi, Peng; Sun, Quanling

    2017-11-01

    A kind of coplanar waveguide triple-band antenna based on defected ground structure is proposed, which has novel structure. Three batches with different frequency band are constructed by utilizing line combination, overlapping, and symmetry method. Stop band signals among three frequency bands are effectively suppressed by slots with different structures. More satisfactory impedance matching is realized by means of changing slot structure and improving return-loss. The presented antenna can operates simultaneously in various systems such as 3G / 4G wireless communication, Bluetooth, Worldwide Interoperability for Microwave Access, Wireless LAN. Test results show that the antenna has good radiation and gain in its working frequency band, and that it has great application potentials.

  8. Band Subset Selection for Hyperspectral Image Classification

    Directory of Open Access Journals (Sweden)

    Chunyan Yu

    2018-01-01

    Full Text Available This paper develops a new approach to band subset selection (BSS for hyperspectral image classification (HSIC which selects multiple bands simultaneously as a band subset, referred to as simultaneous multiple band selection (SMMBS, rather than one band at a time sequentially, referred to as sequential multiple band selection (SQMBS, as most traditional band selection methods do. In doing so, a criterion is particularly developed for BSS that can be used for HSIC. It is a linearly constrained minimum variance (LCMV derived from adaptive beamforming in array signal processing which can be used to model misclassification errors as the minimum variance. To avoid an exhaustive search for all possible band subsets, two numerical algorithms, referred to as sequential (SQ and successive (SC algorithms are also developed for LCMV-based SMMBS, called SQ LCMV-BSS and SC LCMV-BSS. Experimental results demonstrate that LCMV-based BSS has advantages over SQMBS.

  9. Device for measuring semiconductor radiation sources

    International Nuclear Information System (INIS)

    Schubert, W.; Wendt, H.; Doss, R.

    1975-01-01

    In a measuring device, the determination of the local dependence of the intensity and/or the delay time of the recombination radiation on the radiation band of a semiconductor radiation source is reduced to phase measuring so as to enable short delays at 10 -11 seconds to be determined. The measuring device comprises an excitation source for a semiconductor radiation source, a magnifying optical system which images the semiconductor radiation source on a diaphragm having a radiation receiver in its rear. A phasemeter connected to the excitation receiver on the one hand and to the radiation receiver on the other, compares the phase of the excitation signal to the phase of the received signal. The image of the semiconductor radiation source is displaceable relatively to the diaphragm and can be viewed through an observation system. (auth)

  10. A Novel Dual-Band Circularly Polarized Rectangular Slot Antenna

    Directory of Open Access Journals (Sweden)

    Biao Li

    2016-01-01

    Full Text Available A coplanar waveguide fed dual-band circularly polarized rectangular slot antenna is presented. The proposed antenna consists of a rectangular metal frame acting as a ground and an S-shaped monopole as a radiator. The spatial distribution of the surface current density is employed to demonstrate that the circular polarization is generated by the S-shaped monopole which controls the path of the surface currents. An antenna prototype, having overall dimension 37 × 37 × 1 mm3, has been fabricated on FR4 substrate with dielectric constant 4.4. The proposed antenna achieves 10 dB return loss bandwidths and 3 dB axial ratio (AR in the frequency bands 2.39–2.81 GHz and 5.42–5.92 GHz, respectively. Both these characteristics are suitable for WLAN and WiMAX applications.

  11. Aerosol Properties From Combined Oxygen A Band Radiances and Lidar

    Science.gov (United States)

    Winker, Dave; Zhai, Peng-Wang; Hu, Yongxiang

    2015-01-01

    We have developed a new aerosol retrieval technique based on combing high-resolution A band spectra with lidar profiles. Our goal is the development of a technique to retrieve aerosol absorption, one of the critical parameters affecting the global radiation budget and one which is currently poorly constrained by satellite measurements. Our approach relies on two key factors: 1) the use of high spectral resolution (17,000:1) measurements which resolve the A-band line structure, and 2) the use of co-located lidar profile measurements to constrain the vertical distribution of scatterers in the forward model. The algorithm has been developed to be applied to observations from the CALIPSO and OCO-2 satellites, flying in formation as part of the A-train constellation. We describe the approach and present simulated retrievals to illustrate performance potential.

  12. A PHOTONIC BAND GAP FIBRE

    DEFF Research Database (Denmark)

    1999-01-01

    An optical fibre having a periodicidal cladding structure provididing a photonic band gap structure with superior qualities. The periodical structure being one wherein high index areas are defined and wherein these are separated using a number of methods. One such method is the introduction...... of additional low index elements, another method is providing elongated elements deformed in relation to a circular cross section. Also described is a cladding structure comprising elongated elements of a material having an index of refraction higher than that of the material adjacent thereto. Using...

  13. Prenatal diagnosis of amniotic band syndrome

    Directory of Open Access Journals (Sweden)

    Laxmi Devi Padmanabhan

    2016-01-01

    Full Text Available Amniotic band can cause a broad spectrum of anomalies ranging from simple band constrictions to major craniofacial and visceral defects. It can cause significant neonatal morbidity. Accurate diagnosis will help in the management of the present pregnancy and in counseling with regard to future pregnancies. Here we report three cases of amniotic band syndrome detected in the prenatal period.

  14. High-energy band structure of gold

    DEFF Research Database (Denmark)

    Christensen, N. Egede

    1976-01-01

    The band structure of gold for energies far above the Fermi level has been calculated using the relativistic augmented-plane-wave method. The calculated f-band edge (Γ6-) lies 15.6 eV above the Fermi level is agreement with recent photoemission work. The band model is applied to interpret...

  15. Multi-band Modelling of Appearance

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille; Larsen, Rasmus

    2002-01-01

    the appearance of both derived feature bands and an intensity band. As a special case of feature-band augmented appearance modelling we propose a dedicated representation with applications to face segmentation. The representation addresses a major problem within face recognition by lowering the sensitivity...

  16. Multi-band Modelling of Appearance

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille; Larsen, Rasmus

    2003-01-01

    the appearance of both derived feature bands and an intensity band. As a special case of feature-band augmented appearance modelling we propose a dedicated representation with applications to face segmentation. The representation addresses a major problem within face recognition by lowering the sensitivity...

  17. Lunar Noise-Temperature Increase Measurements at S-Band, X-Band, and Ka-Band Using a 34-Meter-Diameter Beam-Waveguide Antenna

    Science.gov (United States)

    Morabito, D. D.

    2006-08-01

    The Moon radiates energy at infrared and microwave wavelengths, in addition to reflecting sunlight at optical wavelengths. As a result, an antenna pointed at or near the Moon will cause an increase in receiver noise temperature that needs to be accounted for in telemetry, radio science, or ranging link budgets. The Deep Space Network may be required to use its antennas in future lunar robotic or human missions, and thus it is important to understand the nature of this temperature increase as a function of observing frequency, lunar phase, and angular offset of the antenna beam from the center of the lunar disk. This article quantifies such a set of measurements acquired at DSS 13, a 34-m-diameter research and development beam-waveguide antenna located at Goldstone, California, at three different telecommunication frequencies, S-band (2.3 GHz), X-band (8.4 GHz), and Ka-band (32 GHz), over a wide range of lunar phase, for both disk-centered and limb-centered positions of the antenna beam.

  18. Reconfigurable L-Band Radar

    Science.gov (United States)

    Rincon, Rafael F.

    2008-01-01

    The reconfigurable L-Band radar is an ongoing development at NASA/GSFC that exploits the capability inherently in phased array radar systems with a state-of-the-art data acquisition and real-time processor in order to enable multi-mode measurement techniques in a single radar architecture. The development leverages on the L-Band Imaging Scatterometer, a radar system designed for the development and testing of new radar techniques; and the custom-built DBSAR processor, a highly reconfigurable, high speed data acquisition and processing system. The radar modes currently implemented include scatterometer, synthetic aperture radar, and altimetry; and plans to add new modes such as radiometry and bi-static GNSS signals are being formulated. This development is aimed at enhancing the radar remote sensing capabilities for airborne and spaceborne applications in support of Earth Science and planetary exploration This paper describes the design of the radar and processor systems, explains the operational modes, and discusses preliminary measurements and future plans.

  19. Design and Realization of a Planar Ultrawideband Antenna with Notch Band at 3.5 GHz

    Science.gov (United States)

    2014-01-01

    A small antenna with single notch band at 3.5 GHz is designed for ultrawideband (UWB) communication applications. The fabricated antenna comprises a radiating monopole element and a perfectly conducting ground plane with a wide slot. To achieve a notch band at 3.5 GHz, a parasitic element has been inserted in the same plane of the substrate along with the radiating patch. Experimental results shows that, by properly adjusting the position of the parasitic element, the designed antenna can achieve an ultrawide operating band of 3.04 to 11 GHz with a notched band operating at 3.31–3.84 GHz. Moreover, the proposed antenna achieved a good gain except at the notched band and exhibits symmetric radiation patterns throughout the operating band. The prototype of the proposed antenna possesses a very compact size and uses simple structures to attain the stop band characteristic with an aim to lessen the interference between UWB and worldwide interoperability for microwave access (WiMAX) band. PMID:25133245

  20. Design and Realization of a Planar Ultrawideband Antenna with Notch Band at 3.5 GHz

    Directory of Open Access Journals (Sweden)

    Rezaul Azim

    2014-01-01

    Full Text Available A small antenna with single notch band at 3.5 GHz is designed for ultrawideband (UWB communication applications. The fabricated antenna comprises a radiating monopole element and a perfectly conducting ground plane with a wide slot. To achieve a notch band at 3.5 GHz, a parasitic element has been inserted in the same plane of the substrate along with the radiating patch. Experimental results shows that, by properly adjusting the position of the parasitic element, the designed antenna can achieve an ultrawide operating band of 3.04 to 11 GHz with a notched band operating at 3.31–3.84 GHz. Moreover, the proposed antenna achieved a good gain except at the notched band and exhibits symmetric radiation patterns throughout the operating band. The prototype of the proposed antenna possesses a very compact size and uses simple structures to attain the stop band characteristic with an aim to lessen the interference between UWB and worldwide interoperability for microwave access (WiMAX band.

  1. Models for the water-ice librational band in cool dust: possible observational test

    Science.gov (United States)

    Robinson, G.

    2014-01-01

    Of all the water-ice (H2O-ice) bands the librational band, occurring at a wavelength of about 12 μm, has proved to be the most difficult to detect observationally and also to reproduce in radiative transfer models. In fact, the case for the positive identification of the feature is strong in only a few astronomical objects. A previously suggested explanation for this is that so-called radiative transfer effects may mask the feature. In this paper, radiative transfer models are produced which unambiguously reveal the presence of the librational band as a separate resolved feature provided that there is no dust present which radiates significantly in the 10-μm region, specifically silicate-type dust. This means that the maximum dust temperature must be ≲50 K. In this case, the models indicate that the librational band may clearly be observed as an absorption feature against the stellar continuum. This suggests that the feature may be best observed by obtaining the 10-μm spectrum of stars either with very cool circumstellar dust shells, with Tmax ≲ 50 K, or those without circumstellar dust shells at all but with interstellar extinction. The first option might, however, require unrealistically large amounts of dust in the circumstellar shell in order to produce measurable absorption. Thus, the best place to look for the water-ice librational band may not be protostars with the remnants of their dust cloud still present, or evolved objects with ejected dust shells, as one might first think, because of the warm dust (Tmax ≫ 50 K) usually present in the shells of these objects. If objects associated with very cool dust exclusively do show the 3.1-μm water-ice band in deep absorption, but the librational band still does not appear, this may imply that it is not radiative transfer effects which suppress the librational band, and that some other mechanism for its suppression is in play. One possibility is that a low water-ice to silicate abundance may mask the

  2. Photonic Band Gap Accelerator Demonstration at Ku-Band.

    CERN Document Server

    Smirnova, Evgenya I; Edwards, Randall L; Kesar, Amit S; Mastovsky, Ivan; Shapiro, Michael A; Temkin, Richard J

    2005-01-01

    We report progress on the design and cold test of a metal Ku-band PBG accelerator structure. The 17.140 GHz 6-cell PBG accelerator structure with reduced long-range wakefields was designed for the experiment. The copper structure was electroformed and cold-tested. Tuning was performed through chemical etching of the rods. Final cold test measurements were found to be in very good agreement with the design. The structure will be installed on the beam line at the accelerator laboratory at Massachusetts Institute of Technology and will be powered with 3 MW of peak power from the Haimson 17.14 GHz klystron. Results of the design, fabrication, cold test and hot test on the Haimson accelerator will be presented.

  3. Dust bands in the asteroid belt

    International Nuclear Information System (INIS)

    Sykes, M.V.; Greenberg, R.; Dermott, S.F.; Nicholson, P.D.; Burns, J.A.

    1989-01-01

    This paper describes the original IRAS observations leading to the discovery of the three dust bands in the asteroid belt and the analysis of data. Special attention is given to an analytical model of the dust band torus and to theories concerning the origin of the dust bands, with special attention given to the collisional equilibrium (asteroid family), the nonequilibrium (random collision), and the comet hypotheses of dust-band origin. It is noted that neither the equilibrium nor nonequilibrium models, as currently formulated, present a complete picture of the IRAS dust-band observations. 32 refs

  4. Ultra Wide Band (UWB) Antenna Design for Metal Monitoring

    OpenAIRE

    Pratiwi, A. Asmi; Palantei, Elyas; Areni, Intan Sari; Djamaluddin, Dewiani

    2014-01-01

    UWB microstrip antenna has been designed using UWB technology and the principle of Microwave Imaging system that works at UWB frequencies. The Simulation performed using Ansoft HFSS version 13 software to construct the microstrip antenna with some important parameters, such as reflection coefficient (S) and radiation pattern. This purpose of the antenna is fetal detecting and monitoring system in dual band at (2.54 - 4.45) GHz with the bandwidth of 1.91 GHz and (6.53 -7.97) GHz with the b...

  5. RFID antenna design for circular polarization in UHF band

    Science.gov (United States)

    Shahid, Hamza; Khan, Muhammad Talal Ali; Tayyab, Umais; Irshad, Usama Bin; Alkhazraji, Emad; Javaid, Muhammad Sharjeel

    2017-05-01

    A miniature half cross dipole antenna for defense and aerospace RFID applications in UHF band is presented. The dipole printed line arms are half crossed shape on top of dielectric substrate backed by reactive impedance surface. The antenna fed by a coaxial cable at the gap separating the dipole arms. Our design is intended to work at 2.42 GHz for RFID readers. The radiation pattern obtained has HPBW of 112, return loss of 22.24 dB and 90 MHz bandwidth.

  6. The limiting efficiency of band gap graded solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Rafat, Nadia H. [Faculty of Engineering, Cairo University, Giza (Egypt); Habib, S.E.D. [Faculty of electronics and communication, Cairo University, Giza (Egypt)

    1998-09-04

    Two fundamental mechanisms limit the maximum attainable efficiency of solar cells, namely the radiative recombination and Auger recombination. We show in this paper that proper band gap grading of the solar cell localizes the Auger recombination around the metallurgical junction. Two beneficial effects result from this Auger recombination localization; first the cell is less sensitive to the surface conditions, and second, the previous estimates for the limiting efficiency of solar cells by Shockley, Tiedje, and Green are revised upwardly. We calculate the optimum bandgap grading profile for several real material systems, including GaInAsP lattice matched to InP, and a-SiGe on a-Si substrate

  7. An attenuation Layer for Electromagnetic Shielding in X- Band Frequency

    Directory of Open Access Journals (Sweden)

    vida Zaroushani

    2015-06-01

    Full Text Available Uncontrolled exposure to X-band frequency leads to health damage. One of the principles of radiation protection is shielding. But, conventional shielding materials have disadvantages. Therefore, studies of novel materials, as an alternative to conventional shielding materials, are required to obtain new electromagnetic shielding material. Therefore, this study investigated the electromagnetic shielding of two component epoxy thermosetting resin for the X - band frequency with workplace approach. Two components of epoxy resin mixed according to manufacturing instruction with the weight ratio that was 100:10 .Epoxy plates fabricated in three different thicknesses (2, 4 and 6mm and shielding effectiveness measured by Vector Network Analyzer. Then, shielding effectiveness measured by the scattering parameters.The results showed that 6mm thickness of epoxy had the highest and 2mm had the lowest average of shielding effectiveness in X-band frequency that is 4.48 and 1.9 dB, respectively. Also, shielding effectiveness increased by increasing the thickness. But this increasing is useful up to 4mm. Percentage shielding effectiveness of attenuation for 6, 4 and 2mm thicknesses is 64.35%, 63.31% and 35.40%. Also, attenuation values for 4mm and 6mm thicknesses at 8.53 GHz and 8.52 GHz frequency are 77.15% and 82.95%, respectively, and can be used as favourite shields for the above frequency. 4mm-Epoxy is a suitable candidate for shielding application in X-band frequency range but, in the lower section, 6mm thickness is recommended. Finely, the shielding matrix can be used for selecting the proper thickness for electromagnetic shielding in X- Band frequency.

  8. Impact of head modeling and sensor types in localizing human gamma-band oscillations.

    Science.gov (United States)

    Mideksa, K G; Hoogenboom, N; Hellriegel, H; Krause, H; Schnitzler, A; Deuschl, G; Raethjen, J; Heute, U; Muthuraman, M

    2014-01-01

    An effective mechanism in neuronal communication is oscillatory neuronal synchronization. The neuronal gamma-band (30-100 Hz) synchronization is associated with attention which is induced by a certain visual stimuli. Numerous studies have shown that the gamma-band activity is observed in the visual cortex. However, impact of different head modeling techniques and sensor types to localize gamma-band activity have not yet been reported. To do this, the brain activity was recorded using 306 magnetoencephalography (MEG) sensors, consisting of 102 magnetometers and 102 pairs of planar gradiometers (one measuring the derivative of the magnetic field along the latitude and the other along the longitude), and the data were analyzed with respect to time, frequency, and location of the strongest response. The spherical head models with a single-shell and overlapping spheres (local sphere) have been used as a forward model for calculating the external magnetic fields generated from the gamma-band activity. For each sensor type, the subject-specific frequency range of the gamma-band activity was obtained from the spectral analysis. The identified frequency range of interest with the highest gamma-band activity is then localized using a spatial-filtering technique known as dynamic imaging of coherent sources (DICS). The source analysis for all the subjects revealed that the gradiometer sensors which measure the derivative along the longitude, showed sources close to the visual cortex (cuneus) as compared to the other gradiometer sensors which measure the derivative along the latitude. However, using the magnetometer sensors, it was not possible to localize the sources in the region of interest. When comparing the two head models, the local-sphere model helps in localizing the source more focally as compared to the single-shell head model.

  9. Giemsa C-banding of Barley Chromosomes. I: Banding Pattern Polymorphism

    DEFF Research Database (Denmark)

    Linde-Laursen, Ib

    1978-01-01

    Twenty barley (Hordeum vulgare) lines studied had a common basic chromosome banding pattern. Most bands ranged from medium to very small in size. The most conspicuous banding occurred at or near the centromeres, in the proximal, intercalary parts of most chromosome arms and beside the secondary c...... 7. Seventeen differently banded karyotypes were found. Some banding pattern polymorphisms can be used in cytological and cytogenetic studies....

  10. Photonic band gap structure simulator

    Science.gov (United States)

    Chen, Chiping; Shapiro, Michael A.; Smirnova, Evgenya I.; Temkin, Richard J.; Sirigiri, Jagadishwar R.

    2006-10-03

    A system and method for designing photonic band gap structures. The system and method provide a user with the capability to produce a model of a two-dimensional array of conductors corresponding to a unit cell. The model involves a linear equation. Boundary conditions representative of conditions at the boundary of the unit cell are applied to a solution of the Helmholtz equation defined for the unit cell. The linear equation can be approximated by a Hermitian matrix. An eigenvalue of the Helmholtz equation is calculated. One computation approach involves calculating finite differences. The model can include a symmetry element, such as a center of inversion, a rotation axis, and a mirror plane. A graphical user interface is provided for the user's convenience. A display is provided to display to a user the calculated eigenvalue, corresponding to a photonic energy level in the Brilloin zone of the unit cell.

  11. Radiation Therapy

    Science.gov (United States)

    ... radiation may be external, from special machines, or internal, from radioactive substances that a doctor places inside your body. The type of radiation therapy you receive depends on many factors, including The ...

  12. Radiation safety

    International Nuclear Information System (INIS)

    Woods, D.A.

    1982-01-01

    Sections include: dose units, dose limits, dose rate, potential hazards of ionizing radiations, control of internal and external radiation exposure, personal dosemeters, monitoring programs and transport of radioactive material (packaging and shielding)

  13. Radiation Therapy

    Science.gov (United States)

    ... kill any cancer cells that remain. Lifetime Dose Limits There is a limit to the amount of radiation an area of ... total dose of radiation more quickly or to limit damage to healthy cells. Different ways of delivering ...

  14. Radiation Emergencies

    Science.gov (United States)

    ... amounts of radiation and could be caused by Dirty bombs - a mix of explosives with radioactive powder Fallout from a nuclear bomb Accidental release from a nuclear reactor or a nuclear weapons plant A lot of radiation over a short ...

  15. Broad-band beam buncher

    International Nuclear Information System (INIS)

    Goldberg, D.A.; Flood, W.S.; Arthur, A.A.; Voelker, F.

    1986-01-01

    This patent describes a broad-band beam buncher. This beam buncher consists of: a housing adapted to be eacuated, an electron gun in the housing for producing a beam of electrons, buncher means in the housing forming a buncher cavity which has an entrance opening for receiving the electron beam and an exit opening through which the electron beam passes out of the buncher cavity, a drift tube electrode in the buncher cavity and disposed between the entrance opening and the exit opening with first and second gaps between the drift tube electrode and the entrance and exit openings, the drift tube electrode which has a first drift space through which the electron beam passes in traveling between the entrance and exit openings, modulating means for supplying an ultrahigh frequeny modulating signal to the drift tube electrode for producing velocity modulation of the electrons in the electron beam as the electrons pass through the buncher cavity and the drift tube electrode between the entrance opening and the exit opening, drift space means in the housing forming a second drift space for receiving the velocity modulated electron beam from the exit opening, the velocity modulated electron beam being bunched as it passes along the second drift space, the drift space means has a discharge opening through which the electron beam is discharged from the second drift space after being bunched therein, the modulating means containing a signal source for producing an ultrahigh frequency signal, a transmission line connected between the signal source and the drift tube electrode, and terminating means connected to the drift tube electrode for terminating the transmission line in approximately its characteristic impedance to afford a broad response band with minimum 6 variations therein

  16. Medical radiation

    Energy Technology Data Exchange (ETDEWEB)

    1992-06-01

    This leaflet in the At-a-Glance Series describes the medical use of X-rays, how X-rays help in diagnosis, radiation protection of the patient, staff protection, how radioactive materials in nuclear medicine examinations help in diagnosis and the use of radiation in radiotherapy. Magnetic resonance imaging, a diagnostic technique involving no ionizing radiation, is also briefly examined. The role of the NRPB in the medical use of radiation is outlined. (UK).

  17. Dual band-notched monopole antenna with enhanced bandwidth for ultra-wideband wireless communications

    Directory of Open Access Journals (Sweden)

    Mohammad Akbari

    2014-08-01

    Full Text Available A new configuration of an ultra-wideband (UWB dual band-notched antenna is presented. The designed geometry consists of octagonal radiating patch, a 50 Ω microstrip feed-line on the front and an asymmetric partial ground on the back. For impedance bandwidth enhancement, a unilateral stepped structure is utilised on the ground. By etching two E-shaped slots connected to each other on the radiating patch and applying E-shaped defected ground structure on the back, dual notched bands are achieved. The antenna is printed on a low profile FR4 substrate with a compact size of 25 × 18 × 1 mm^3. The experimental results indicate that the antenna has an impedance bandwidth from 2.55 to 21.65 GHz for voltage standing wave ratio ≤2, except the notched bands on worldwide interoperability for microwave access and wireless local area network bands. Moreover, stable radiation patterns and gains within the operating band are shown.

  18. The dynamics of a shear band

    Science.gov (United States)

    Giarola, Diana; Capuani, Domenico; Bigoni, Davide

    2018-03-01

    A shear band of finite length, formed inside a ductile material at a certain stage of a continued homogeneous strain, provides a dynamic perturbation to an incident wave field, which strongly influences the dynamics of the material and affects its path to failure. The investigation of this perturbation is presented for a ductile metal, with reference to the incremental mechanics of a material obeying the J2-deformation theory of plasticity (a special form of prestressed, elastic, anisotropic, and incompressible solid). The treatment originates from the derivation of integral representations relating the incremental mechanical fields at every point of the medium to the incremental displacement jump across the shear band faces, generated by an impinging wave. The boundary integral equations (under the plane strain assumption) are numerically approached through a collocation technique, which keeps into account the singularity at the shear band tips and permits the analysis of an incident wave impinging a shear band. It is shown that the presence of the shear band induces a resonance, visible in the incremental displacement field and in the stress intensity factor at the shear band tips, which promotes shear band growth. Moreover, the waves scattered by the shear band are shown to generate a fine texture of vibrations, parallel to the shear band line and propagating at a long distance from it, but leaving a sort of conical shadow zone, which emanates from the tips of the shear band.

  19. Radiation watchdog

    International Nuclear Information System (INIS)

    Manning, R.

    1984-01-01

    Designated by WHO as a Collaborating Centre, the Radiation Emergency Assistance Center/Training Site (REAC/TS) in Oak Ridge, Tennessee provides assistance to all countries of the Americas in radiation accidents including human contamination or overexposure. It also conducts courses in radiation emergency response for health professionals from throughout the world

  20. Radiation Exposure

    Science.gov (United States)

    Radiation is energy that travels in the form of waves or high-speed particles. It occurs naturally in sunlight. Man-made radiation is used in X-rays, nuclear weapons, nuclear power plants and cancer treatment. If you are exposed to small amounts of radiation over a long ...

  1. Optical radiation in modern medicine.

    Science.gov (United States)

    Sowa, Paweł; Rutkowska-Talipska, Joanna; Rutkowski, Krzysztof; Kosztyła-Hojna, Bożena; Rutkowski, Ryszard

    2013-08-01

    Optical radiation extends between microwaves and X-rays of the electromagnetic radiation and includes ultraviolet (UV), visible light (VL) and infrared (IR) components. The dose of radiation that reaches the skin is influenced by the ozone layer, position of the Sun, latitude, altitude, cloud cover and ground reflections. The photobiological effects of UV, VL and IR bands depend on their wavelength, frequency and mechanism of action. They are modified by the thickness, structure, vasculature and pigmentation of skin's stratum corneum, epidermis and dermis. Following absorption, IR affects the body mainly through transfer of thermal energy to tissues. Visible light and skin interact either thermally or photochemically, whereas UV acts mainly photochemically. Optical radiation in the form of sunlight therapy had been used already in ancient times. Nowadays IR, VL and UV are widely applied in the therapy of allergic, dermatological, cardiovascular, respiratory, rheumatic, neonatal, pediatric and psychiatric disorders.

  2. Characterization of a Dual-Polarized Connected-Dipole Array for Ku-Band Mobile Terminals

    NARCIS (Netherlands)

    Bolt, R.J.; Cavallo, D.; Gerini, G.; Deurloo, D.; Grooters, R.; Neto, A.; Toso, G.

    2016-01-01

    In this paper, we present the characterization of a Ku-band connected-dipole array for mobile Satcom application. The prototype array consists of 2 × 256 dipole radiators arranged in a square grid, to form 16 × 16 dual-polarized cells. It has been designed to operate over a wideband ranging from

  3. Comparison of Model Prediction With Measurements of Galactic Background Noise at L-Band

    DEFF Research Database (Denmark)

    Le Vine, David M.; Abraham, Saji; Kerr, Yann H.

    2005-01-01

    The spectral window at L-band (1.413 GHz) is important for passive remote sensing of surface parameters such as soil moisture and sea surface salinity that are needed to understand the hydrological cycle and ocean circulation. Radiation from celestial sources (mostly galactic) is strong in this w...

  4. A Very Compact and Low Profile UWB Planar Antenna with WLAN Band Rejection

    Directory of Open Access Journals (Sweden)

    Avez Syed

    2016-01-01

    Full Text Available A low-cost coplanar waveguide fed compact ultrawideband (UWB antenna with band rejection characteristics for wireless local area network (WLAN is proposed. The notch band characteristic is achieved by etching half wavelength C-shaped annular ring slot in the radiating patch. By properly choosing the radius and position of the slot, the notch band can be adjusted and controlled. With an overall size of 18.7 mm × 17.6 mm, the antenna turns out to be one of the smallest UWB antennas with band-notched characteristics. It has a wide fractional bandwidth of 130% (2.9–13.7 GHz with VSWR < 2 and rejecting IEEE 802.11a and HIPERLAN/2 frequency band of 5.1–5.9 GHz. Stable omnidirectional radiation patterns in the H plane with an average gain of 4.4 dBi are obtained. The band-notch mechanism of the proposed antenna is examined by HFSS simulator. A good agreement is found between measured and simulated results indicating that the proposed antenna is well suited for integration into portable devices for UWB applications.

  5. A Novel Compact UWB Monopole Antenna with Bluetooth and Triple Notch Band

    Science.gov (United States)

    Li, Li; Zhou, Zhi-Li; Hong, Jing-Song

    2013-01-01

    A novel technique to add an extra Bluetooth band and triple notch bands simultaneously to a compact ultra-wideband (UWB) monopole antenna is presented. This scissors-shaped UWB antenna, covering 2.9 GHz-12.5 GHz, is fed by a special microstrip line. To create an extra Bluetooth band centered at 2.45 GHz, an arc-shaped stub is attached to the high concentrated current area right of the feed line and a rectangular slot is etched in the radiation patch. Besides, a notch band for WLAN (5.6 GHz-6.15 GHz) is also obtained. In addition, by connecting two asymmetric stubs to the feed line, two other notch bands in 3.28 GHz-3.8 GHz for WiMAX and 7.1 GHz-7.76 GHz for downlink of X-band satellite communication systems are achieved. The proposed antenna with compact size of 20 mm × 26 mm is fabricated and measured, showing stable antenna gain and good omni-directional radiation patterns in H-plane.

  6. Design of UWB Planar Monopole Antennas with Etched Spiral Slot on the Patch for Multiple Band-Notched Characteristics

    Directory of Open Access Journals (Sweden)

    Swarup Das

    2015-01-01

    Full Text Available Three types of Ultrawideband (UWB antennas with single, double, and triple notched bands are proposed and investigated for UWB communication applications. The proposed antennas consist of CPW fed monopole with spiral slot etched on the patch. In this paper single, double, and also triple band notches with central frequency of 3.57, 5.12, and 8.21 GHz have been generated by varying the length of a single spiral slot. The proposed antenna is low-profile and of compact size. A stable gain is obtained throughout the operation band except the three notched frequencies. The antennas have omnidirectional and stable radiation patterns across all the relevant bands. Moreover, relatively consistent group delays across the UWB frequencies are noticed for the triple notched band antenna. A prototype of the UWB antenna with triple notched bands is fabricated and the measured results of the antenna are compared with the simulated results.

  7. Dual-Band On-Body Repeater Antenna for In-on-On WBAN Applications

    Directory of Open Access Journals (Sweden)

    Jinpil Tak

    2013-01-01

    Full Text Available A dual-band on-body repeater antenna for in-on-on wireless body area network applications is proposed. The proposed antenna has a maximum radiation normal to the human-body surface for communication with implanted devices in the 5.8 GHz industrial, scientific, and medical (ISM band. In addition, to transmit the biological information received from the implanted devices to other on-body devices, the proposed antenna was designed to have a monopole-like radiation pattern along the surface of the human body for communication in the 2.45 GHz ISM band. The antenna was fabricated, and its performance was measured by attaching it to a human-equivalent semisolid phantom. In addition, the human-body effect was studied to ensure antenna performance under an actual situation.

  8. Pulsar radiation as polarized shot noise

    International Nuclear Information System (INIS)

    Cordes, J.M.

    1976-01-01

    Pulsar radiation can be resonably modeled as amplitude-modulated shot noise for which the amplitude modulations correspond to the subpulses and micropulses that comprise the structure of single pulses. The shot noise fluctuates on nanosecond time scales and therefore has a bandwidth typical of pulsars, namely, 1-10 GHz. If curvature radiation from bunches of coherently radiating particles is the relevant radiation mechanism, then the radiation from a single bunch corresponds to a shot pulse; such a physical interpretation is not crucial to the validity of the shot noise model, however. We calculate some statistics of the corresponding signal in a narrow-band receiver system, an informative one being the intensity modulation index of the narrow-band noise from which it can be determined whether or not the noise has Gaussian statistics. Departures from Gaussian statistics can occur if intensity variations are due primarily to changes in the number of particles radiating coherently at any instant. If the temporal density of shot pulses is sufficiently high, however, only Gaussian statistics will be observed, meaning that extensive incoherent addition occurs in the generation and the propagation of the radiation.The first and second moments of the Stokes parameters of narrow-band signals are derived for both time-independent and time-variable polarization. It is shown how the polarization properties of short time scale structure can be determined from the autocorrelation functions of the Stokes parameters

  9. Radiation imaging

    Energy Technology Data Exchange (ETDEWEB)

    Redmayne, I.

    1986-05-21

    A detector for the detection of radiation such as X-ray radiation comprises an array of scintillation elements embedded in a sheet of radiation absorbing material. The scintillation elements are monitored individually, for example by a corresponding array of photodiodes, to build up a picture of the incident radiation. The front face of the sheet and the inner walls of the bores may be coated with a reflective material. The detector finds particular application in weld radiography. The detector may be stepped relative to the radiation source, the signals produced by the rows of the detector as they pass a predetermined point being summed.

  10. Radiation imaging

    International Nuclear Information System (INIS)

    Redmayne, Ian.

    1986-01-01

    A detector for the detection of radiation such as X-ray radiation comprises an array of scintillation elements embedded in a sheet of radiation absorbing material. The scintillation elements are monitored individually, for example by a corresponding array of photodiodes, to build up a picture of the incident radiation. The front face of the sheet and the inner walls of the bores may be coated with a reflective material. The detector finds particular application in weld radiography. The detector may be stepped relative to the radiation source, the signals produced by the rows of the detector as they pass a predetermined point being summed. (author)

  11. Band Structure Analysis of La0.7Sr0.3MnO3 Perovskite Manganite Using a Synchrotron

    Directory of Open Access Journals (Sweden)

    Hong-Sub Lee

    2015-01-01

    Full Text Available Oxide semiconductors and their application in next-generation devices have received a great deal of attention due to their various optical, electric, and magnetic properties. For various applications, an understanding of these properties and their mechanisms is also very important. Various characteristics of these oxides originate from the band structure. In this study, we introduce a band structure analysis technique using a soft X-ray energy source to study a La0.7Sr0.3MnO3 (LSMO oxide semiconductor. The band structure is formed by a valence band, conduction band, band gap, work function, and electron affinity. These can be determined from secondary electron cut-off, valence band spectrum, O 1s core electron, and O K-edge measurements using synchrotron radiation. A detailed analysis of the band structure of the LSMO perovskite manganite oxide semiconductor thin film was established using these techniques.

  12. Adaptive Confidence Bands for Nonparametric Regression Functions.

    Science.gov (United States)

    Cai, T Tony; Low, Mark; Ma, Zongming

    2014-01-01

    A new formulation for the construction of adaptive confidence bands in non-parametric function estimation problems is proposed. Confidence bands are constructed which have size that adapts to the smoothness of the function while guaranteeing that both the relative excess mass of the function lying outside the band and the measure of the set of points where the function lies outside the band are small. It is shown that the bands adapt over a maximum range of Lipschitz classes. The adaptive confidence band can be easily implemented in standard statistical software with wavelet support. Numerical performance of the procedure is investigated using both simulated and real datasets. The numerical results agree well with the theoretical analysis. The procedure can be easily modified and used for other nonparametric function estimation models.

  13. Radiation induced luminescence processes in c-BN

    DEFF Research Database (Denmark)

    Trinkler, L.; Berzina, B.; Benabdesselam, M.

    2004-01-01

    is determined by the excitation type: blue, green (dominant) and red bands are observed in PL, ultraviolet, blue (dominant), green and red bands-in XL. Three thermal peaks are found in TL curves in the 0-700degreesC temperature range, their presence and intensity depend on radiation type used. A tentative...

  14. X-BAND KLYSTRON DEVELOPMENT AT SLAC

    Energy Technology Data Exchange (ETDEWEB)

    Vlieks, Arnold E.; /SLAC

    2009-08-03

    The development of X-band klystrons at SLAC originated with the idea of building an X-band Linear Collider in the late 1980's. Since then much effort has been expended in developing a reliable X-band Power source capable of delivering >50 MW RF power in pulse widths >1.5 {micro}s. I will report on some of the technical issues and design strategies which have led to the current SLAC klystron designs.

  15. ANALISIS TIPOGRAFI PADA LOGOTYPE BAND FORGOTTEN

    OpenAIRE

    Atang Riyan Isnandar; wantoro wantoro wantoro

    2016-01-01

    Abstrak Forgotten merupakan band asal kota Bandung yang beraliran death metal. Band ini telah memiliki beberapa album yang cukup sukses. Salah satu faktor yang turut berperan penting dalam album-album Forgotten adalah desain sampul album. Sampul album merupakan identitas dan pesan dari musik yang dibawakan oleh Forgotten. Dalam sampul album, terdapat salah satu elemen visual yaitu Tipografi. Salah satu peran tipografi dalam sampul album Forgotten adalah sebagai logotype dari band. Yang menar...

  16. A Low Profile Ultrawide Band Monopole Antenna for Wearable Applications

    Directory of Open Access Journals (Sweden)

    Srinivas Doddipalli

    2017-01-01

    Full Text Available A low profile pentagonal shaped monopole antenna is designed and presented for wearable applications. The main objective of this paper is to design a miniaturized ultrawide band monopole planar antenna which can work efficiently in free space but also on the surface of the human body. The impact of human tissues on antenna performance is explained using the proposed pentagonal monopole antenna. The antenna is designed with a pentagonal radiator and a matched feed line of 50 ohm and square slots are integrated on defected ground of FR4 substrate with a size of 15 mm × 25 mm to achieve ultrawide band (UWB performance in free space and human proximity. This overall design will enhance the antenna performance with wide bandwidth ranging from 2.9 GHz to 11 GHz. Specific absorption rate (SAR of the proposed antenna on dispersive phantom model is also measured to observe the exposure of electromagnetic energy on human tissues. The simulated and measured results of the proposed antenna exhibit wide bandwidth and radiation characteristics in both free space and human proximity.

  17. Group IV direct band gap photonics: Methods, Challenges and Opportunities

    Directory of Open Access Journals (Sweden)

    Richard eGeiger

    2015-07-01

    Full Text Available The concept of direct band gap group IV materials offers a paradigm change for Si-photonics concerning the monolithic implementation of light emitters: The idea is to integrate fully compatible group IV materials with equally favorable optical properties as the chemically incompatible group III-V-based systems. The concept involves either mechanically applied strain on Ge or alloying of Ge with Sn and permits to drastically improve the insufficient radiative efficiency of Ge. The favorable optical properties result from a modified band structure transformed from an indirect to a direct one. The first demonstration of such a direct band gap laser, accomplished in GeSn, exemplifies the capability of this new concept. These systems may permit a qualitative as well as a quantitative expansion of Si-photonics into traditional but also new areas of applications, provided they can be operated energy efficiently, under ambient conditions and integrated with current Si technologies. This review aims to discuss the challenges along this path in terms of fabrication, characterization and fundamental understanding, and will elaborate on evoking opportunities of this new class of group IV-based laser materials.

  18. The Smallest Form Factor UWB Antenna with Quintuple Rejection Bands for IoT Applications Utilizing RSRR and RCSRR.

    Science.gov (United States)

    Rahman, MuhibUr; Park, Jung-Dong

    2018-03-19

    In this paper, we present the smallest form factor microstrip-fed ultra-wideband antenna with quintuple rejection bands for use in wireless sensor networks, mobile handsets, and Internet of things (IoT). Five rejection bands have been achieved at the frequencies of 3.5, 4.5, 5.25, 5.7, and 8.2 GHz, inseminating four rectangular complementary split ring resonators (RCSRRs) on the radiating patch and placing two rectangular split-ring resonators (RSRR) near the feedline-patch junction of the conventional ultra-wideband (UWB) antenna. The design guidelines of the implemented notched bands are provided at the desired frequency bands and analyzed. The measured results demonstrate that the proposed antenna delivers a wide impedance bandwidth from 3 to 11 GHz with a nearly omnidirectional radiation pattern, high rejection in the multiple notched-bands, and good radiation efficiency over the entire frequency band except at the notched frequencies. Simulated and measured response match well specifically at the stop-bands.

  19. The Smallest Form Factor UWB Antenna with Quintuple Rejection Bands for IoT Applications Utilizing RSRR and RCSRR

    Directory of Open Access Journals (Sweden)

    MuhibUr Rahman

    2018-03-01

    Full Text Available In this paper, we present the smallest form factor microstrip-fed ultra-wideband antenna with quintuple rejection bands for use in wireless sensor networks, mobile handsets, and Internet of things (IoT. Five rejection bands have been achieved at the frequencies of 3.5, 4.5, 5.25, 5.7, and 8.2 GHz, inseminating four rectangular complementary split ring resonators (RCSRRs on the radiating patch and placing two rectangular split-ring resonators (RSRR near the feedline-patch junction of the conventional ultra-wideband (UWB antenna. The design guidelines of the implemented notched bands are provided at the desired frequency bands and analyzed. The measured results demonstrate that the proposed antenna delivers a wide impedance bandwidth from 3 to 11 GHz with a nearly omnidirectional radiation pattern, high rejection in the multiple notched-bands, and good radiation efficiency over the entire frequency band except at the notched frequencies. Simulated and measured response match well specifically at the stop-bands.

  20. Computational Design of Flat-Band Material

    Science.gov (United States)

    Hase, I.; Yanagisawa, T.; Kawashima, K.

    2018-02-01

    Quantum mechanics states that hopping integral between local orbitals makes the energy band dispersive. However, in some special cases, there are bands with no dispersion due to quantum interference. These bands are called as flat band. Many models having flat band have been proposed, and many interesting physical properties are predicted. However, no real compound having flat band has been found yet despite the 25 years of vigorous researches. We have found that some pyrochlore oxides have quasi-flat band just below the Fermi level by first principles calculation. Moreover, their valence bands are well described by a tight-binding model of pyrochlore lattice with isotropic nearest neighbor hopping integral. This model belongs to a class of Mielke model, whose ground state is known to be ferromagnetic with appropriate carrier doping and on-site repulsive Coulomb interaction. We have also performed a spin-polarized band calculation for the hole-doped system from first principles and found that the ground state is ferromagnetic for some doping region. Interestingly, these compounds do not include magnetic element, such as transition metal and rare-earth elements.

  1. Computational Design of Flat-Band Material.

    Science.gov (United States)

    Hase, I; Yanagisawa, T; Kawashima, K

    2018-02-26

    Quantum mechanics states that hopping integral between local orbitals makes the energy band dispersive. However, in some special cases, there are bands with no dispersion due to quantum interference. These bands are called as flat band. Many models having flat band have been proposed, and many interesting physical properties are predicted. However, no real compound having flat band has been found yet despite the 25 years of vigorous researches. We have found that some pyrochlore oxides have quasi-flat band just below the Fermi level by first principles calculation. Moreover, their valence bands are well described by a tight-binding model of pyrochlore lattice with isotropic nearest neighbor hopping integral. This model belongs to a class of Mielke model, whose ground state is known to be ferromagnetic with appropriate carrier doping and on-site repulsive Coulomb interaction. We have also performed a spin-polarized band calculation for the hole-doped system from first principles and found that the ground state is ferromagnetic for some doping region. Interestingly, these compounds do not include magnetic element, such as transition metal and rare-earth elements.

  2. Blackbody radiation functions and polylogarithms

    International Nuclear Information System (INIS)

    Stewart, Seán M.

    2012-01-01

    A new method based on the polylogarithm function is used to derive an exact expression for the fractional emissive power of a blackbody in any arbitrary spectral band. Compared to all previously used methods the polylogarithm based method is unsurpassed in its simplicity. Displacement laws for the centroid of blackbody radiation in the linear wavelength and frequency spectral representations that make use of the polylogarithm based approach are also given.

  3. A U-Shaped Slot UWB Antenna with Flexible and Wide Tunable Dual Notch Band

    Directory of Open Access Journals (Sweden)

    Zhang Zhongmin

    2016-01-01

    Full Text Available A coplanar waveguide (CPW fed ultra-wideband (UWB antenna with flexible and wide tunable dual bandnotched characteristics is proposed in this paper. The dual band-notched function is achieved by using an U-shaped slot inserted into the ellipse radiation patch and by using an elliptic parasitic slit placed near the ground plane. The wide tunable band-notched characteristic is implemented by adjusting the length of U-shaped slot and by adjusting the length of ellipse parasitic slit. The design aims to achieve wide reconfigurable band-notched features on the UWB antenna. The simulated results indicate that the proposed antenna has a wide bandwidth (VSWR under 2 from 2.9GHz to 12.6GHz with fractional bandwidth of 125%, and has a wide tunable notch band center frequency from 4.5GHz to 12.4GHz.

  4. Miniaturized Band-notched UWB Antenna with Improved Fidelity Factor and Pattern Stability

    Directory of Open Access Journals (Sweden)

    R. Sanyal

    2018-04-01

    Full Text Available This article presents a novel miniaturized monopole UWB antenna with enhanced band rejection characteristics at 5.5 GHz. The proposed configuration is derived from octagonal band notched UWB antenna which consists of W-shaped slotted ground plane and an open ended λ_g/4 hook shaped resonator as a band-notched element. By using proper miniaturization of the octagonal monopole and ground plane, 50% reduction in main structure can be realized without changing the dimension of resonator. Frequency and time domain performance of the proposed miniaturized antenna design is compared with conventional half size and full size structures. The noticeable improvements in terms of band rejection characteristics, radiation pattern stability and fidelity factor confirm the effectiveness of the proposed miniaturization technique. Furthermore, the proposed antenna provides much wider operating bandwidth (VSWR less than 2 within 3.1-17.2 GHz with the exception around 5-6 GHz.

  5. A compact 5.5 GHz band-rejected UWB antenna using complementary split ring resonators.

    Science.gov (United States)

    Islam, M M; Faruque, M R I; Islam, M T

    2014-01-01

    A band-removal property employing microwave frequencies using complementary split ring resonators (CSRRs) is applied to design a compact UWB antenna wishing for the rejection of some frequency band, which is meanwhile exercised by the existing wireless applications. The reported antenna comprises optimization of a circular radiating patch, in which slotted complementary SRRs are implanted. It is printed on low dielectric FR4 substrate material fed by a partial ground plane and a microstrip line. Validated results exhibit that the reported antenna shows a wide bandwidth covering from 3.45 to more than 12 GHz, with a compact dimension of 22 × 26 mm(2), and VSWR < 2, observing band elimination of 5.5 GHz WLAN band.

  6. A Very Compact and Low Profile UWB Planar Antenna with WLAN Band Rejection.

    Science.gov (United States)

    Syed, Avez; Aldhaheri, Rabah W

    2016-01-01

    A low-cost coplanar waveguide fed compact ultrawideband (UWB) antenna with band rejection characteristics for wireless local area network (WLAN) is proposed. The notch band characteristic is achieved by etching half wavelength C-shaped annular ring slot in the radiating patch. By properly choosing the radius and position of the slot, the notch band can be adjusted and controlled. With an overall size of 18.7 mm × 17.6 mm, the antenna turns out to be one of the smallest UWB antennas with band-notched characteristics. It has a wide fractional bandwidth of 130% (2.9-13.7 GHz) with VSWR antenna is examined by HFSS simulator. A good agreement is found between measured and simulated results indicating that the proposed antenna is well suited for integration into portable devices for UWB applications.

  7. A Compact 5.5 GHz Band-Rejected UWB Antenna Using Complementary Split Ring Resonators

    Directory of Open Access Journals (Sweden)

    M. M. Islam

    2014-01-01

    Full Text Available A band-removal property employing microwave frequencies using complementary split ring resonators (CSRRs is applied to design a compact UWB antenna wishing for the rejection of some frequency band, which is meanwhile exercised by the existing wireless applications. The reported antenna comprises optimization of a circular radiating patch, in which slotted complementary SRRs are implanted. It is printed on low dielectric FR4 substrate material fed by a partial ground plane and a microstrip line. Validated results exhibit that the reported antenna shows a wide bandwidth covering from 3.45 to more than 12 GHz, with a compact dimension of 22 × 26 mm2, and VSWR < 2, observing band elimination of 5.5 GHz WLAN band.

  8. Conformal Band-Notch UWB Monopole Antenna on Finite Cylindrical Substrates

    Directory of Open Access Journals (Sweden)

    E. S. Ahmed

    2013-06-01

    Full Text Available A microstrip-fed new UWB monopole antenna with a band-notch characteristic mounted on the finite cylindrical surface is presented. The proposed antenna consists of a rectangular metal radiation patch fed by a 50 ohm microstrip line and a rectangular ground plane. To achieve ultra-wideband, three modifications are introduced. The first one is to blend the upper and lower corners of the radiating plates. The second one is to remove a circular section from the radiating metal. The third one is to blend the upper corners of the ground plane. The antenna is designed on a substrate with dielectric constant εr=3 and 1.6 mm height. The proposed antenna is conformed on finite cylindrical substrates of radiuses 4, 5 and 6 cm. The cylindrical structures were simulated through CST microwave studio finite element package. The simulation results, obtained via CST package on the return losses, VSWR and radiation pattern of the antenna are presented. For both planar and conformal antennas, results show that the impedance bandwidth of the designed antenna is from 2-18 GHz with a return loss less than -10 dB (VSWR<2 and a band rejection of 5-6 GHz for wireless LAN (WLAN, that includes the band 5.15-5.825 GHz limited by IEEE 802.11.a and HIPERLAN/2 with return loss greater than -10dB. The proposed simple shaped conformal antenna provides a good radiation pattern and gain between 3.84 and 5.96 dBi over the entire frequency band excluding the rejected band.

  9. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with the design and measurement of physical parameters used in theory or to support biological experiments. The radiation biophysics program tests and uses the theoretical developments for experimental design, and provides information for further theoretical development through experiments on cellular systems

  10. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with design and measurement of those physical parameters used in the theory or to support biological experiments. The radiation biophysics program tests and makes use of the theoretical developments for experimental design. Also, this program provides information for further theoretical development through experiments on cellular systems

  11. Atoms, Radiation, and Radiation Protection

    CERN Document Server

    Turner, James E

    2007-01-01

    Atoms, Radiation, and Radiation Protection offers professionals and advanced students a comprehensive coverage of the major concepts that underlie the origins and transport of ionizing radiation in matter. Understanding atomic structure and the physical mechanisms of radiation interactions is the foundation on which much of the current practice of radiological health protection is based. The work covers the detection and measurement of radiation and the statistical interpretation of the data. The procedures that are used to protect man and the environment from the potential harmful effects of

  12. Spontaneous reduction of the prolapsed stomach in a case of anterior band slippage after laparoscopic adjustable gastric banding.

    Science.gov (United States)

    Darius, T; Aelvoet, Ch; Tollens, T; Vanrykel, J P

    2007-01-01

    Band slippage is a common late complication after laparoscopic adjustable gastric banding. We present the first report in literature of a spontaneous reduction of the prolapsed stomach after band deflation in a case of anterior band slippage.

  13. Red shift in spectra of galaxies as a consequence of gravitational radiation of the same level as electromagnetic

    OpenAIRE

    Fisenko, S. I.; Fisenko, I. S.

    2010-01-01

    In elaboration of the results presented earlier the red shift is also regarded in this investigation as a widening of electromagnetic radiation spectra, determined by the existence of gravitational radiation of a banded spectrum of the same level as electromagnetic.

  14. Design Variations on Planar Differential Antenna with Potential for Multiple, Wide, and Narrow Band Coverage

    Directory of Open Access Journals (Sweden)

    Domenico Pepe

    2015-01-01

    Full Text Available This paper presents three practical antenna implementations based on variations of one general planar differential antenna topology originally proposed for ultrawideband (UWB applications. All designs were implemented on a low-cost FR4 substrate and experimentally characterized in an anechoic chamber. The results show how the proposed design variations lead to the required antenna performances and how they give rise to new opportunities in terms of coverage of wide, narrow, and multiple frequency bands for communication and sensing applications below 5 GHz. In particular, the results show how a significant enhancement in bandwidth performance is achieved by folding the differential radiating elements. Moreover, they show how an agile design strategy enables adaption of the antenna design to different requirements for covering wide, narrow, and multiple bands, making the proposed class of antennas suitable for different wireless applications. In detail, the proposed class of antennas covers multiple frequency bands, ranging from the 868 MHz and 915 MHz bands to 2.4 GHz industrial scientific and medical (ISM bands, including the 1.2 GHz L band for Global Positioning and Navigation Satellite Systems (GNSS and the lower portion of the UWB band.

  15. A Planar UWB Antenna with Switchable Single/Double Band-Rejection Characteristics

    Directory of Open Access Journals (Sweden)

    V. Sharbati

    2016-09-01

    Full Text Available In this Paper, a reconfigurable antenna with capability to operate in the ultrawideband (UWB mode from 2.85 to 14.4 GHz with switchable notch bands of 3.25–4.26 GHz, 5.1–5.9 GHz or 7.1-7.8 GHz, is presented. The proposed antenna has a simple configuration and compact size of 17 × 14 mm2. To make the band-notches, three methods (methods of slot antenna, parasitic patches and backplane structure are used. To achieve the reconfigurability, three PIN diode are placed on the proposed antenna. A PIN diode is inserted over the L-shaped parasitic element and the rectangular patch, another one is placed between the two parasitic elements on the ground plane, and other across the square ring-shaped slot, respectively. Antenna performance can be changed by adjusting the status of the PIN diodes that make the band-notches in applications bands (WLAN, WiMAX/C-band and X-band. Good group delay and monopole-like radiation pattern characteristics are achieved in the frequency band of interest. The antenna performance both by simulation and by experiment indicates that it is suitable and a good candidate for UWB applications.

  16. A Flexible Monopole Antenna with Dual-Notched Band Function for Ultrawideband Applications

    Directory of Open Access Journals (Sweden)

    Xiaoyan Zhang

    2014-01-01

    Full Text Available We present a flexible ultrawideband (UWB planar monopole antenna with dual-notched band characteristic printed on a polyimide substrate. The antenna is fed by a step coplanar waveguide (CPW that provides smooth transitional impedance for improved matching. It operates from 2.76 to 10.6 GHz with return loss greater than 10 dB except for the notch band to reduce the interference with existing 3.5 GHz WiMAX band and 5.5 GHz WLAN band. With a combination of rectangular and circle patches in which the U-shaped slot is carved, the overall size of antenna is 30 mm × 20 mm. Moreover, a pair of arc-shaped stubs located at both sides of the feed line is utilized to create the notch band for WiMAX band. The results also show that the antenna has omnidirectional radiation pattern and smooth gain over the entire operational band.

  17. Response of avocado genotypes to improvement through {sup 60}Co gamma radiation; Respuesta de diversos genotipos de aguacate al mejoramiento por radiacion gamma de {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, E. De la; Rubi A, M.; Garcia A, J.M. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    Ten avocado genotypes were subjected to gamma radiation from 0 to 45 Gy in 1993. Vegetative and reproductive data were analysed in a factorial design. Genotypes differed significative on height and fruit number. Radiation affected significative fruit number but not tree height. ''Hass'' showed strongest interaction between genotype and doses, for fruit number. (Author)

  18. Solid State KA-Band, Solid State W-Band and TWT Amplifiers, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Phase I of the proposal describes plans to develop a state of the art transmitter for the W-Band and KA -Band Cloud Radar system. Our focus will be concentrated in...

  19. Radiation carcinogenesis

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1976-01-01

    The risk of iatrogenic tumors with radiation therapy is so outweighed by the benefit of cure that estimates of risk have not been considered necessary. However, with the introduction of chemotherapy, combined therapy, and particle radiation therapy, the comparative risks should be examined. In the case of radiation, total dose, fractionation, dose rate, dose distribution, and radiation quality should be considered in the estimation of risk. The biological factors that must be considered include incidence of tumors, latent period, degree of malignancy, and multiplicity of tumors. The risk of radiation induction of tumors is influenced by the genotype, sex, and age of the patient, the tissues that will be exposed, and previous therapy. With chemotherapy the number of cells at risk is usually markedly higher than with radiation therapy. Clearly the problem of the estimation of comparative risks is complex. This paper presents the current views on the comparative risks and the importance of the various factors that influence the estimation of risk

  20. Radiation acoustics

    CERN Document Server

    Lyamshev, Leonid M

    2004-01-01

    Radiation acoustics is a developing field lying at the intersection of acoustics, high-energy physics, nuclear physics, and condensed matter physics. Radiation Acoustics is among the first books to address this promising field of study, and the first to collect all of the most significant results achieved since research in this area began in earnest in the 1970s.The book begins by reviewing the data on elementary particles, absorption of penetrating radiation in a substance, and the mechanisms of acoustic radiation excitation. The next seven chapters present a theoretical treatment of thermoradiation sound generation in condensed media under the action of modulated penetrating radiation and radiation pulses. The author explores particular features of the acoustic fields of moving thermoradiation sound sources, sound excitation by single high-energy particles, and the efficiency and optimal conditions of thermoradiation sound generation. Experimental results follow the theoretical discussions, and these clearl...

  1. Handwashing, sanitation and family planning practices are the strongest underlying determinants of child stunting in rural indigenous communities of Jharkhand and Odisha, Eastern India: a cross-sectional study.

    Science.gov (United States)

    Saxton, Jennifer; Rath, Shibanand; Nair, Nirmala; Gope, Rajkumar; Mahapatra, Rajendra; Tripathy, Prasanta; Prost, Audrey

    2016-10-01

    The World Health Organisation has called for global action to reduce child stunting by 40% by 2025. One third of the world's stunted children live in India, and children belonging to rural indigenous communities are the worst affected. We sought to identify the strongest determinants of stunting among indigenous children in rural Jharkhand and Odisha, India, to highlight key areas for intervention. We analysed data from 1227 children aged 6-23.99 months and their mothers, collected in 2010 from 18 clusters of villages with a high proportion of people from indigenous groups in three districts. We measured height and weight of mothers and children, and captured data on various basic, underlying and immediate determinants of undernutrition. We used Generalised Estimating Equations to identify individual determinants associated with children's height-for-age z-score (HAZ; p family planning, reducing diarrhoeal infections, improving handwashing practices, increasing access to income and strengthening health and sanitation infrastructure. © 2016 The Authors. Maternal & Child Nutrition published by John Wiley & Sons Ltd.

  2. Photoacoustic Spectroscopy of - and - Dependence in the O_{2} A-Band

    Science.gov (United States)

    Cich, Matthew J.; Lunny, Elizabeth M.; Stroscio, Gautam; Bui, Thinh Quoc; Rupasinghe, Priyanka; Hogan, Daniel; Bray, Caitlin; Long, David A.; Hodges, Joseph T.; Crawford, Timothy J.; Miller, Charles; Drouin, Brian; Okumura, Mitchio

    2017-06-01

    NASA's Orbiting Carbon Observatory missions OCO-2 and OCO-3 require spectroscopic parameterization of the Oxygen A-Band absorption (757-775 nm) with unprecedented precision, to deliver space-based measurements of CO_{2} column densities with an accuracy of better than 0.1%. Furthermore, with the long satellite-based pathlengths, the strongest A-Band lines are saturated. Accurate retrievals of O_{2} column densities thus require precise modeling of the line shape, including the wings several linewidths from line center. The line shape model must go beyond the Voigt profile to include higher order effects such as Dicke narrowing, speed dependence, line mixing (LM), and collision-induced absorption (CIA). High precision laboratory data targeting these effects must be taken. Line mixing and collision induced absorption have proven to be especially problematic in satellite retrievals of O_{2} column densities. LM and CIA are more prominent at lower temperatures and higher pressures. A temperature-stabilized photoacoustic spectrometer was therefore designed to study the temperature- and pressure-dependence of spectral line shapes at temperatures from 230-296 K and pressures up to 5 atm. Progress toward high resolution (2 MHz) measurements of the full A-Band will be presented. The observed lineshapes are analyzed with the Hartmann-Tran Profile (HTP), which incorporates LM and CIA , using the Labfit multispectrum fitting program, and the determination of LM and CIA effects will be presented.

  3. Hawking radiation

    Science.gov (United States)

    Parentani, Renaud; Spindel, Philippe

    2011-12-01

    Hawking radiation is the thermal radiation predicted to be spontaneously emitted by black holes. It arises from the steady conversion of quantum vacuum fluctuations into pairs of particles, one of which escaping at infinity while the other is trapped inside the black hole horizon. It is named after the physicist Stephen Hawking who derived its existence in 1974. This radiation reduces the mass of black holes and is therefore also known as black hole evaporation.

  4. Maximizing band gaps in plate structures

    DEFF Research Database (Denmark)

    Halkjær, Søren; Sigmund, Ole; Jensen, Jakob Søndergaard

    2006-01-01

    Band gaps, i.e., frequency ranges in which waves cannot propagate, can be found in elastic structures for which there is a certain periodic modulation of the material properties or structure. In this paper, we maximize the band gap size for bending waves in a Mindlin plate. We analyze an infinite...

  5. Link adaptation in unlicensed radio bands

    NARCIS (Netherlands)

    Haartsen, J.C.; Schutter, George B.W.

    2005-01-01

    This paper presents a new collaborative mechanism for efficient coordination of radio communication devices, in particular addressing the unlicensed ISM band at 2.4 GHz. As the traffic in the ISM band is increasing tremendously, the potential for interference between uncoordinated devices is

  6. Symptomatic mesodiverticular bands in children | Bertozzi | Annals ...

    African Journals Online (AJOL)

    Symptomatic mesodiverticular bands in children. ... Abstract. Objective: The aim of this study was to review the English literature about a rare condition such as symptomatic mesodiverticular bands (MDBs) in children. Background: The MDB is an ... All cases reported an intestinal occlusion as clinical picture. Internal hernia ...

  7. Concert Band Instrumentation: Realities and Remedies.

    Science.gov (United States)

    Rogers, George L.

    1991-01-01

    Suggests ways to solve problems resulting from imbalanced instrumentation in school concert bands. Identifies sources of imbalance. Encourages band directors to plan for correct instrumentation, to match students' characteristics and abilities to instruments, and to recruit students to play needed instruments. Discusses the benefits of balanced…

  8. Low band gap polymers for organic photovoltaics

    DEFF Research Database (Denmark)

    Bundgaard, Eva; Krebs, Frederik C

    2007-01-01

    Low band gap polymer materials and their application in organic photovoltaics (OPV) are reviewed. We detail the synthetic approaches to low band gap polymer materials starting from the early methodologies employing quinoid homopolymer structures to the current state of the art that relies...... in photovoltaic applications and give a tabular overview of rarely applied materials....

  9. Complex band structure and electronic transmission eigenchannels

    DEFF Research Database (Denmark)

    Jensen, Anders; Strange, Mikkel; Smidstrup, Soren

    2017-01-01

    molecular junctions. The molecular junctions show that both the length dependence of the total transmission and the individual transmission eigenvalues can be, almost always, found through the complex band structure. The complex band structure of the semi-conducting material, however, does not predict...

  10. Stop! Look! Listen! for Effective Band Rehearsals.

    Science.gov (United States)

    Townsend, Alfred S.

    2003-01-01

    Discusses how band conductors can develop student skills in three areas: (1) when the conductor stops the band; (2) teaching the students to pay attention and watch the conductor; and (3) improving the student listening skills. Includes information on instructing students to play chorales. (CMK)

  11. Conduction bands in classical periodic potentials

    Indian Academy of Sciences (India)

    a quantum particle in a conduction band and drift at a constant average velocity through the potential as if it were undergoing resonant tunnelling. The classical conduction bands for this potential are determined numerically with high precision. Keywords. PT symmetry; complex trajectories; complex classical mechanics; ...

  12. Artificial Oxide Heterostructures with Tunable Band Gap

    Science.gov (United States)

    2016-12-20

    tunable band gap and band structures in epitaxial grown CaMnO3. The efforts have been devoted to (1) the thin film growth; (2) the tunable optical...plan to pursue a claim for personal or organizational intellectual property? Changes in research objectives (if any): Change in AFOSR Program Officer

  13. Error Analysis of Band Matrix Method

    OpenAIRE

    Taniguchi, Takeo; Soga, Akira

    1984-01-01

    Numerical error in the solution of the band matrix method based on the elimination method in single precision is investigated theoretically and experimentally, and the behaviour of the truncation error and the roundoff error is clarified. Some important suggestions for the useful application of the band solver are proposed by using the results of above error analysis.

  14. Low-Noise Band-Pass Amplifier

    Science.gov (United States)

    Kleinberg, L.

    1982-01-01

    Circuit uses standard components to overcome common limitation of JFET amplifiers. Low-noise band-pass amplifier employs JFET and operational amplifier. High gain and band-pass characteristics are achieved with suitable choice of resistances and capacitances. Circuit should find use as low-noise amplifier, for example as first stage instrumentation systems.

  15. Deformed configurations, band structures and spectroscopic ...

    Indian Academy of Sciences (India)

    2014-03-20

    Mar 20, 2014 ... nuclei, e.g., in 16O (Z = N = 8) [12,13] and 56Ni (Z = N = 28) [14–16], coexisting with the spherical ground configuration. Recently, Hwang et al [2] have observed deformed rotational bands in 82Ge. To our knowledge, these deformed rotational bands have not been studied theoretically so far though there ...

  16. Atomic-Monolayer MoS2 Band-to-Band Tunneling Field-Effect Transistor

    KAUST Repository

    Lan, Yann Wen

    2016-09-05

    The experimental observation of band-to-band tunneling in novel tunneling field-effect transistors utilizing a monolayer of MoS2 as the conducting channel is demonstrated. Our results indicate that the strong gate-coupling efficiency enabled by two-dimensional materials, such as monolayer MoS2, results in the direct manifestation of a band-to-band tunneling current and an ambipolar transport.

  17. Radiation protection

    International Nuclear Information System (INIS)

    1989-01-01

    A NRPB leaflet in the 'At-a-Glance' series explains in a simple but scientifically accurate way what radiation is, the biological effects and the relative sensitivity of different parts of the human body. The leaflet then discusses radiation protection principles, radiation protection in the UK and finally the effectiveness of this radiation protection as judged by a breakdown of the total dose received by an average person in the UK, a heavy consumer of Cumbrian seafood, an average nuclear industry worker and an average person in Cornwall. (UK)

  18. GRAVITATIONAL RADIATION

    Directory of Open Access Journals (Sweden)

    Metin SALTIK

    1996-03-01

    Full Text Available According to classical electromagnetic theory, an accelerated charge or system of charges radiates electromagnetic waves. In a radio transmitter antenna charges are accelerated along the antenna and release electromagnetic waves, which is radiated at the velocity of light in the surrounding medium. All of the radio transmitters work on this principle today. In this study an analogy is established between the principles by which accelerated charge systems markes radiation and the accelerated mass system, and the systems cousing gravitational radiation are investigated.

  19. Radiation medicine

    International Nuclear Information System (INIS)

    1991-01-01

    This booklet has been produced by UKAEA and the Marie Curie Memorial Foundation to give some basic information about what radiation is and how it is used in day to day diagnosis and treatment. It will be of interest to people undergoing treatment, their relatives and friends, and anyone who wants to know more about this important area. After a brief historical introduction the booklet explains what radiation is, the natural and man-made sources of radiation, how it is produced and how X-rays are used in medical diagnosis and treatment. The radiation protection measures taken and safety standards followed are mentioned. (author)

  20. Radiation and radiation protection; Strahlung und Strahlenschutz

    Energy Technology Data Exchange (ETDEWEB)

    Bartholomaeus, Melanie (comp.)

    2017-04-15

    The publication of the Bundesamt fuer Strahlenschutz covers the following issues: (i) Human beings in natural and artificial radiation fields; (ii) ionizing radiation: radioactivity and radiation, radiation exposure and doses; measurement of ionizing radiation, natural radiation sources, artificial radiation sources, ionizing radiation effects on human beings, applied radiation protection, radiation exposure of the German population, radiation doses in comparison; (iii) non-ionizing radiation; low-frequency electric and magnetic fields, high-frequency electromagnetic fields, optical radiation; (iiii) glossary, (iv) units and conversion.

  1. Band-type microelectrodes for amperometric immunoassays

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ga-Yeon; Chang, Young Wook; Ko, Hyuk [Department of Materials Science and Engineering, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul, 120-749 (Korea, Republic of); Kang, Min-Jung [Korea Institute of Science and Technology (KIST), Seoul (Korea, Republic of); Pyun, Jae-Chul, E-mail: jcpyun@yonsei.ac.kr [Department of Materials Science and Engineering, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul, 120-749 (Korea, Republic of)

    2016-07-20

    A band-type microelectrode was made using a parylene-N film as a passivation layer. A circular-type, mm-scale electrode with the same diameter as the band-type microelectrode was also made with an electrode area that was 5000 times larger than the band-type microelectrode. By comparing the amperometric signals of 3,5,3′,5′-tetramethylbenzidine (TMB) samples at different optical density (OD) values, the band-type microelectrode was determined to be 9 times more sensitive than the circular-type electrode. The properties of the circular-type and the band-type electrodes (e.g., the shape of their cyclic voltammograms, the type of diffusion layer used, and the diffusion layer thickness per unit electrode area) were characterized according to their electrode area using the COMSOL Multiphysics software. From these simulations, the band-type electrode was estimated to have the conventional microelectrode properties, even when the electrode area was 100 times larger than a conventional circular-type electrode. These results show that both the geometry and the area of an electrode can influence the properties of the electrode. Finally, amperometric analysis based on a band-type electrode was applied to commercial ELISA kits to analyze human hepatitis B surface antigen (hHBsAg) and human immunodeficiency virus (HIV) antibodies. - Highlights: • A band-type microelectrode was made using a parylene-N film as a passivation layer. • The band-type microelectrode was 14-times more sensitive than circular-type electrode. • The influence of geometry on microelectrode properties was simulated using COMSOL. • The band-type electrode was applied to ELISA kits for hHBsAg and hHIV-antibodies.

  2. Near-infrared diffuse interstellar bands in APOGEE telluric standard star spectra . Weak bands and comparisons with optical counterparts

    Science.gov (United States)

    Elyajouri, M.; Lallement, R.; Monreal-Ibero, A.; Capitanio, L.; Cox, N. L. J.

    2017-04-01

    Aims: Information on the existence and properties of diffuse interstellar bands (DIBs) outside the optical domain is still limited. Additional infra-red (IR) measurements and IR-optical correlative studies are needed to constrain DIB carriers and locate various absorbers in 3D maps of the interstellar matter. Methods: We extended our study of H-band DIBs in Apache Point Observatory Galactic Evolution Experiment (APOGEE) Telluric Standard Star (TSS) spectra. We used the strong λ15273 band to select the most and least absorbed targets. We used individual spectra of the former subsample to extract weaker DIBs, and we searched the two stacked series for differences that could indicate additional bands. High-resolution NARVAL and SOPHIE optical spectra for a subsample of 55 TSS targets were additionally recorded for NIR/optical correlative studies. Results: From the TSS spectra we extract a catalog of measurements of the poorly studied λλ15617, 15653, and 15673 DIBs in ≃300 sightlines, we obtain a first accurate determination of their rest wavelength and constrained their intrinsic width and shape. In addition, we studied the relationship between these weak bands and the strong λ15273 DIB. We provide a first or second confirmation of several other weak DIBs that have been proposed based on different instruments, and we add new constraints on their widths and locations. We finally propose two new DIB candidates. Conclusions: We compared the strength of the λ15273 absorptions with their optical counterparts λλ5780, 5797, 6196, 6283, and 6614. Using the 5797-5780 ratio as a tracer of shielding against the radiation field, we showed that the λ15273 DIB carrier is significantly more abundant in unshielded (σ-type) clouds, and it responds even more strongly than the λ5780 band carrier to the local ionizing field. Full Table 5 is available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc

  3. Laser radiation effect on radiation-induced defects in heavy ion tracks in dielectrics

    International Nuclear Information System (INIS)

    Egorov, A.N.; Zhiryakov, B.M.; Kushin, V.V.; Lyapidevskij, V.K.; Khokhlov, N.B.

    1988-01-01

    Possibility of laser radiation resonance effect on radiation-induced defects in heavy ion tracks in dielectric materials is investigated. Absorption spectra in infrared, visible and ultraviolet ranges for cellulose nitrate samples irradiated by 6 MeV/nucleon 58 Ni ions and reactor gamma radiation are measured. Absorption spectra for irradiated and reference samples are presented. Two absorption bands λ 1 =0.33 μm (E 1 =3.9 eV) and λ 2 =0.72 μm (E 2 =1.7 eV) are detected. Etching rate decrease in a track under laser radiation effect is noticed. 3 refs.; 1 fig

  4. Concepts of radiation protection

    International Nuclear Information System (INIS)

    2013-01-01

    This seventh chapter presents the concepts and principles of safety and radiation protection, emergency situations; NORM and TENORM; radiation protection care; radiation protection plan; activities of the radiation protection service; practical rules of radiation protection and the radiation symbol

  5. Radiation myelopathy

    International Nuclear Information System (INIS)

    Berlit, P.

    1987-01-01

    After a review of the world literature, the case histories of 43 patients with radiation myelopathy are analyzed. In 1 patient there was a radiation injury of the medulla oblongata, in 2, cervical, in 28, thoracic, and in 12, lumbosacral. In the medulla oblongata lesion an alternans syndrome resulted. The patients with cervical and thoracic radiation myelopathies presented with a Brown-Sequard syndrome, a spinalis anterior syndrome or a transversal syndrome with pyramidal and spinothalamic tract involvement as the most prominent signs. For this group the term 'pyramidal-spinothalamic radiation myelopathy' is proposed. In lumbosacral radiation lesions a pure anterior horn syndrome may lead to spinothalamic tract involvement and the development of a cauda conus syndrome. The clinical presentation of these cases suggests that the location of the radiation lesion is most likely the region of the conus medullaris. The most frequent initial symptom was dysesthesia; the patients complained of burning pain or a feeling of coldness. Usually the neurological deficits were progressive, in pyramidal-spinothalamic radiation myelopathy over 12 months in average, in lumbosacral radiation lesions up to 10 years. The latent period between the finish of radiation therapy and the first neurological signs was 8 months (median) in cervical and thoracic myelopathy and 33 months in lumbosacral lesions. For the entire group of 43 patients there was an inverse relationship between the radiation dose (ret) and the latent period. A positive relation could be demonstrated between the age of patients at the time of radiation therapy and the latent period. Patients simultaneously receiving cytostatic drugs presented after a longer latent period than the remaining group. (orig./MG)

  6. Design and Analysis of Ultra-wideband Micro Strip Patch Antenna with Notch Band Characteristics

    Directory of Open Access Journals (Sweden)

    Kumar Omprakash

    2016-01-01

    Full Text Available A new design of ultra-wideband (UWB micro strip patch antenna with notch band characteristic for wireless local area network (WLAN application is presented in this paper. The proposed antenna consists of a rectangular patch with a partial ground plane that is fed by 50 Ω micro strip line. A notch band function is created by inserting overlapped one U-shape and one C-shape slot on the radiator patch, added additional patch to the ground plane side and slit in truncated ground plane. The proposed antenna potentially minimized frequency interference between WLAN and UWB system. This antenna with the size of 26 mm × 32 mm (W×L and the simulated results show that the antenna can operate over the frequency band between 3.1 and 10.45 GHz for voltage standing wave ratio (VSWR > 2 with band notch 5.06-5.825 GHz. Besides in the working band, the antenna shows good radiation pattern in the H-plane and the E-plane and has good time domain characteristic.

  7. Radiation signatures

    International Nuclear Information System (INIS)

    McGlynn, S.P.; Varma, M.N.

    1992-01-01

    A new concept for modelling radiation risk is proposed. This concept is based on the proposal that the spectrum of molecular lesions, which we dub ''the radiation signature'', can be used to identify the quality of the causal radiation. If the proposal concerning radiation signatures can be established then, in principle, both prospective and retrospective risk determination can be assessed on an individual basis. A major goal of biophysical modelling is to relate physical events such as ionization, excitation, etc. to the production of radiation carcinogenesis. A description of the physical events is provided by track structure. The track structure is determined by radiation quality, and it can be considered to be the ''physical signature'' of the radiation. Unfortunately, the uniqueness characteristics of this signature are dissipated in biological systems in ∼10 -9 s. Nonetheless, it is our contention that this physical disturbance of the biological system eventuates later, at ∼10 0 s, in molecular lesion spectra which also characterize the causal radiation. (author)

  8. Radiation hematology

    International Nuclear Information System (INIS)

    Zherbin, E.A.; Chukhlovin, A.B.

    1989-01-01

    State-of-the-Art ofl radiation hematology and review of the problems now facing this brauch of radiobiology and nuclear medicine are presented. Distortion of division and maturation of hemopoiesis parent cells is considered as main factor of radiopathology for hematopoetic system. Problems of radiation injury and functional variation of hematopoetic microenvironment cell populations are discussed. 176 figs.; 23 figs.; 18 tabs

  9. Synchrotron radiation

    International Nuclear Information System (INIS)

    Nave, C.; Quinn, P.; Blake, R.J.

    1988-01-01

    The paper on Synchrotron Radiation contains the appendix to the Daresbury Annual Report 1987/88. The appendix is mainly devoted to the scientific progress reports on the work at the Synchrotron Radiation Source in 1987/8. The parameters of the Experimental Stations and the index to the Scientific Reports are also included in the appendix. (U.K.)

  10. Radiation oncology

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    The Radiation Oncology Division has had as its main objectives both to operate an academic training program and to carry out research on radiation therapy of cancer. Since fiscal year 1975, following a directive from ERDA, increased effort has been given to research. The research activities have been complemented by the training program, which has been oriented toward producing radiation oncologists, giving physicians short-term experience in radiation oncology, and teaching medical students about clinical cancer and its radiation therapy. The purpose of the research effort is to improve present modalities of radiation therapy of cancer. As in previous years, the Division has operated as the Radiation Oncology Program of the Department of Radiological Sciences of the University of Puerto Rico School of Medicine. It has provided radiation oncology support to patients at the University Hospital and to academic programs of the University of Puerto Rico Medical Sciences Campus. The patients, in turn, have provided the clinical basis for the educational and research projects of the Division. Funding has been primarily from PRNC (approx. 40%) and from National Cancer Institute grants channeled through the School of Medicine (approx. 60%). Special inter-institutional relationships with the San Juan Veterans Administration Hospital and the Metropolitan Hospital in San Juan have permitted inclusion of patients from these institutions in the Division's research projects. Medical physics and radiotherapy consultations have been provided to the Radiotherapy Department of the VA Hospital

  11. Background radiation

    International Nuclear Information System (INIS)

    Arnott, D.

    1985-01-01

    The effects of background radiation, whether natural or caused by man's activities, are discussed. The known biological effects of radiation in causing cancers or genetic mutations are explained. The statement that there is a threshold below which there is no risk is examined critically. (U.K.)

  12. 47 CFR 15.209 - Radiated emission limits; general requirements.

    Science.gov (United States)

    2010-10-01

    ...), fundamental emissions from intentional radiators operating under this section shall not be located in the... fundamental emission. For intentional radiators which operate under the provisions of other sections within... incorporated digital device. (g) Perimeter protection systems may operate in the 54-72 MHz and 76-88 MHz bands...

  13. Nonresonant detection of Josephson radiation from thin-film microbridges

    DEFF Research Database (Denmark)

    Sørensen, O. H.; Mygind, Jesper; Pedersen, Niels Falsig

    1977-01-01

    Measurements are reported of the Josephson radiation from microbridges coupled to an X-band receiver via a nonresonant microwave transformer. Although closely coupled to the bridge, the transformer does not modify the bridge properties. We find that near the transition temperature the radiation l...

  14. UV- Radiation Absorption by Ozone in a Model Atmosphere using ...

    African Journals Online (AJOL)

    UV- radiation absorption is studied through variation of ozone transmittance with altitude in the atmosphere for radiation in the 9.6μm absorption band using Goody's model atmosphere with cubic spline interpolation technique to improve the quality of the curve. The data comprising of pressure and temperature at different ...

  15. Radiation sickness

    International Nuclear Information System (INIS)

    Endoh, Masaru; Ishida, Yusei; Saeki, Mitsuaki

    1983-01-01

    The frequency of radiation sickness in 1,060 patients treated at our Department was 12.8 percent. It was frequent in patients with brain cancer (12 percent), whole spine cancer (47 percent), uterus cancer (28 percent), lung cancer (22 percent) and esophagus cancer (12 percent). Radiation sickness following X-irradiation was studied in its relation to patient's age, size of radiation fields, dosis and white blood cell count. However, we could not find any definite clinical feature relevant to occurrence. There are many theories published concerning the mechanism of radiation sickness. Clinical experiences have shown that radiation sickness cannot be explained by one theory alone but by several theories such as those based on psychology, stress or histamine. (author)

  16. Radiation exposure

    International Nuclear Information System (INIS)

    Dalton, L.K.

    1991-01-01

    The book gives accounts of some social and environmental impacts of the developing radiation industries, including the experiences of affected communities and individuals. Its structure is based on a division which has been made between nuclear and non-nuclear radiation sources, because they create distinctly different problems for environmental protection and so for public health policy. The emissions from electronic and electrical installations - the non-nuclear radiations - are dealt with in Part I. Emissions from radioactive substances - the nuclear radiations - are dealt with in Part II. Part III is for readers who want more detailed information about scientific basis of radiation-related biological changes and their associated health effects. 75 refs., 9 tabs., 7 figs., ills

  17. Radiation carcinogenesis

    International Nuclear Information System (INIS)

    Adams, G.E.

    1987-01-01

    In this contribution about carcinogenesis induced by ionizing radiation some radiation dose-response relationships are discussed. Curves are shown of the relation between cell survival and resp. low and high LET radiation. The difference between both curves can be ascribed to endogenous repair mechanisms in the cell. The relation between single-gen mutation frequency and the surviving fractions of irradiated cells indicates that these repairing mechanisms are not error free. Some examples of reverse dose-response relationships are presented in which decreasing values of dose-rate (LET) correspond with increasing radiation induced cell transformation. Finally some molecular aspects of radiation carcinogenesis are discussed. (H.W.). 22 refs.; 4 figs

  18. Anti-citrullinated peptide antibodies are the strongest predictor of clinically relevant radiographic progression in rheumatoid arthritis patients achieving remission or low disease activity: A post hoc analysis of a nationwide cohort in Japan.

    Directory of Open Access Journals (Sweden)

    Tomohiro Koga

    Full Text Available To determine prognostic factors of clinically relevant radiographic progression (CRRP in patients with rheumatoid arthritis (RA achieving remission or low disease activity (LDA in clinical practice.Using data from a nationwide, multicenter, prospective study in Japan, we evaluated 198 biological disease-modifying antirheumatic drug (bDMARD-naïve RA patients who were in remission or had LDA at study entry after being treated with conventional synthetic DMARDs (csDMARDs. CRRP was defined as the yearly progression of modified total Sharp score (mTSS >3.0 U. We performed a multiple logistic regression analysis to explore the factors to predict CRRP at 1 year. We used receiver operating characteristic (ROC curve to estimate the performance of relevant variables for predicting CRRP.The mean Disease Activity Score in 28 joints-erythrocyte sedimentation rate (DAS28-ESR was 2.32 ± 0.58 at study entry. During the 1-year observation, remission or LDA persisted in 72% of the patients. CRRP was observed in 7.6% of the patients. The multiple logistic regression analysis revealed that the independent variables to predict the development of CRRP were: anti-citrullinated peptide antibodies (ACPA positivity at baseline (OR = 15.2, 95%CI 2.64-299, time-integrated DAS28-ESR during the 1 year post-baseline (7.85-unit increase, OR = 1.83, 95%CI 1.03-3.45, and the mTSS at baseline (13-unit increase, OR = 1.22, 95%CI 1.06-1.42.ACPA positivity was the strongest independent predictor of CRRP in patients with RA in remission or LDA. Physicians should recognize ACPA as a poor-prognosis factor regarding the radiographic outcome of RA, even among patients showing a clinically favorable response to DMARDs.

  19. Prostate volume is strongest predictor of cancer diagnosis at transrectal ultrasound-guided prostate biopsy with prostate-specific antigen values between 2.0 and 9.0 ng/mL.

    Science.gov (United States)

    Al-Azab, Rami; Toi, Ants; Lockwood, Gina; Kulkarni, Girish S; Fleshner, Neil

    2007-01-01

    Data have suggested benign prostatic hyperplasia, and not cancer, as the major reason for elevated prostate-specific antigen (PSA) values between 2.0 and 9.0 ng/mL. If this hypothesis were correct, within these ranges, a smaller prostate volume would be a stronger predictor of cancer than the PSA level itself (the relative contribution from cancer is greater in smaller glands). We examined our institutional data set of transrectal ultrasound-guided procedures from 2000 to 2003. We studied patients who presented for their first prostate biopsy with a PSA level of 2.0 to 9.0 ng/mL. The indications for biopsy were elevated age-specific PSA level or abnormal digital rectal examination findings. Other covariates included patient age, abnormal transrectal ultrasound findings, transrectal ultrasound volume, and biopsy sampling scheme. Univariate analyses were used to assess the association between each variable and cancer diagnosis. Multivariate logistic regression modeling was then used to determine the adjusted risk factors for cancer at biopsy. On univariate analyses, all measured covariates were predictive of cancer. On multivariate modeling, the significant risk factors (in order of strength) for positive biopsy findings were smaller prostate volume (odds ratio [OR] 0.26, P <0.001), increasing age (OR 1.72, P <0.001), increasing PSA (OR 1.64, P <0.001), and the presence of hypoechoic lesions (OR 2.42, P <0.001). When the PSA level is in the 2.0 to 9.0 ng/mL range, a smaller prostate volume is the strongest predictor of cancer detection. These data support previous studies suggesting the amount of benign prostatic hyperplasia, and not cancer, as the major factor responsible for elevated PSA.

  20. Radiation Practices. Annual Report 2003

    International Nuclear Information System (INIS)

    Rantanen, E.

    2004-01-01

    A total of 1811 safety licences for the use of radiation were current at the end of 2003. There were 1962 responsible parties engaged in licence-exempt dental X-ray practices, made notifiable to STUK. Regulatory control of the use of radiation was carried out through regular inspections performed at places of use, postal control, guidance, maintenance of a Dose Register and research intended to support the regulatory control. A total of 10 900 workers engaged in radiation work were subject to individual monitoring in 2003. 135 000 dose entries were made in the register maintained by STUK. In no case did the individual dose of any worker exceed the dose limits stipulated in the Radiation Decree. Regulatory control of natural radiation concentrated on radon at workplaces and exposure of aircrews to cosmic radiation. At the end of 2003, 90 workplaces including a total of 141 work areas were subject to ongoing radon monitoring. A total of 2485 pilots and cabin crew members were monitored for exposure to cosmic radiation. Metrological activities continued with calibration and development work as in previous years. The DOS Laboratory of STO joined the international MRA agreement on the 'self declaration principle'. Regulatory control of the use of non-ionizing radiation focused particularly on mobile phones and sun-beds. Mobile phone market control began by measuring the radiation produced by a range of 12 mobile phones of varying type. Spot check inspections were conducted at tanning facilities and a report was completed on radiation safety improvements at such establishments. A method of measurement based on commercial CCD spectroradiometers was developed for spectral measurements of UV phototherapy appliances and sunbeds. The said method is also suitable for measurements at places of use. A new type of magnetometer, which measures peak values over a wide frequency band weighted according to exposure limits, was developed for measuring low frequency magnetic fields. In

  1. Body area networks using IEEE 802156 implementing the ultra wide band physical layer

    CERN Document Server

    Hernandez, Marco; Mucchi, Lorenzo

    2014-01-01

    The market of wearable wireless medical sensors is experiencing a rapid growth and the associated telecommunications services for the healthcare sector are forecast to further increase in the next years. Medical body area networks (MBANs) allow the mobility of patients and medical personnel by facilitating the remote monitoring of patients suffering from chronic or risky diseases. Currently, MBANs are being introduced in unlicensed frequency bands, where the risk of mutual interference with other electronic devices radiating in the same band can be high. Thus, coexistence is an issue on which

  2. Airborne Lidar Measurements of Atmospheric Pressure Made Using the Oxygen A-Band

    Science.gov (United States)

    Riris, Haris; Rodriquez, Michael; Allan, Graham R.; Hasselbrack, William E.; Stephen, Mark A.; Abshire, James B.

    2011-01-01

    We report on airborne measurements of atmospheric pressure using a fiber-laser based lidar operating in the oxygen A-band near 765 nm and the integrated path differential absorption measurement technique. Our lidar uses fiber optic technology and non-linear optics to generate tunable laser radiation at 765 nm, which overlaps an absorption line pair in the Oxygen A-band. We use a pulsed time resolved technique, which rapidly steps the laser wavelength across the absorption line pair, a 20 cm telescope and photon counting detector to measure Oxygen concentrations.

  3. Dual Y-Shaped Monopole Antenna for Dual-Band WLAN/WiMAX Operations

    Directory of Open Access Journals (Sweden)

    Huiqing Zhai

    2014-01-01

    Full Text Available A dual-band design of monopole antenna with two coupled Y-shaped strips for WLAN/WiMAX applications is presented. By the introduction of dual Y-shaped strips, two separated impedance bandwidths of 22.4% (3.28~4.10 GHz and 19.2% (4.90~5.94 GHz can be obtained to meet the specifications of the WLAN/WiMAX communication band applications. The proposed antenna is successfully simulated, designed, and measured, demonstrating the matched impedance and good radiation characteristics with an overall dimension of 17.7×26×1 mm3.

  4. Compact printed high rejection triple band-notch UWB antenna with multiple wireless applications

    Directory of Open Access Journals (Sweden)

    Manish Sharma

    2016-09-01

    Full Text Available In this paper, small printed urn-shape triple notch ultra-wideband (UWB monopole antenna with diverse wireless applications is presented. Notch bands include WiMAX (IEEE802.16 3.30–3.80 GHz, WLAN IEEE802.11a/h/j/n (5.15–5.35 GHz, 5.25–5.35 GHz, 5.47–5.725 GHz, 5.725–5.825 GHz, and X-band downlink satellite system (7.25–7.75 GHz and other multiple wireless services as close range radar (8–12 GHz in X-band & satellite communication (12–18 GHz in Ku-band. By including T-shape stub and etching two C-shaped slots on the radiating patch, triple band-notch function is obtained with measured high band rejection (VSWR = 16.54 at 3.60 GHz, VSWR = 22.35 at 5.64 GHz and VSWR = 6.38 at 7.64 GHz and covers a wide useable fractional bandwidth of 154.56% (2.49–19.41 GHz. In short the antenna offers triple band-notch UWB systems as a compact multifunctional antenna to reduce the number of antennas installed in wireless devices for accessing multiple wireless networks with wide radiation pattern.

  5. Electromagnetic and nuclear radiation detector using micromechanical sensors

    Science.gov (United States)

    Thundat, Thomas G.; Warmack, Robert J.; Wachter, Eric A.

    2000-01-01

    Electromagnetic and nuclear radiation is detected by micromechanical sensors that can be coated with various interactive materials. As the micromechanical sensors absorb radiation, the sensors bend and/or undergo a shift in resonance characteristics. The bending and resonance changes are detected with high sensitivity by any of several detection methods including optical, capacitive, and piezoresistive methods. Wide bands of the electromagnetic spectrum can be imaged with picoJoule sensitivity, and specific absorptive coatings can be used for selective sensitivity in specific wavelength bands. Microcantilevers coated with optical cross-linking polymers are useful as integrating optical radiation dosimeters. Nuclear radiation dosimetry is possible by fabricating cantilevers from materials that are sensitive to various nuclear particles or radiation. Upon exposure to radiation, the cantilever bends due to stress and its resonance frequency shifts due to changes in elastic properties, based on cantilever shape and properties of the coating.

  6. Radiation therapy

    International Nuclear Information System (INIS)

    Bader, J.L.; Glatstein, E.

    1987-01-01

    The radiation oncologist encounters the critically ill immunosuppressed patient in four settings. First, the newly diagnosed cancer patient presents for initial evaluation and treatment, with immunosuppression from the cancer itself, malnutrition, concomitant infectious disease, prior drug or alcohol abuse or other medical problems. Second, the previously treated cancer patient presents with metastatic or recurrent primary cancer causing local symptoms. Immune dysfunction in this setting may be due to prior chemotherapy and/or radiation as well as any of the original factors. Third, the patient previously treated with radiation presents with a life-threatening problem possibly due to complications of prior therapy. In this setting, the radiation oncologist is asked to evaluate the clinical problem and to suggest whether radiation might be causing part or all of the problem and what can be done to treat these sequelae of radiation. Fourth, the patient with a benign diagnosis (not cancer) is seen with a problem potentially emeliorated by radiation (e.g., kidney transplant rejection, preparation for transplant, or intractable rheumatoid arthritis). This chapter reviews these four issues and presents clinical and radiobiologic principles on which recommendations for therapy are based

  7. Beneficial radiation?

    International Nuclear Information System (INIS)

    Roth, E.; Feinendegen, E.

    1996-01-01

    Ionizing radiation is harmful and may cause cancer, as is well known. However, again and again, low doses of ionizing radiation, under certain conditions, are said to have beneficial effects on human health and, in particular, may reduce the cancer rate. This effect, which is discussed controversially in the technical and scientific literature, is called 'hormesis'. Studies of possible positive effects of ionizing radiation are becoming increasingly more important in scientific research. The article is an attempt to show, by the model case of cancer, under what conditions such positive health effects can occur, at least in principle, and will also contain rough plausibility assessments of the existence of such conditions. Aspects not covered include other existing or presumed positive biological effects of ionizing radiation, such as acceleration of growth, or general increase in the life expectancy of organisms. Also genetic damage will not be discussed in greater detail, despite the existence of some parallels with cancer, both cases constituting lesions to the genetic material of the cells, in one case, germ cells and, in the case of cancer, somatic cells. Also, acute radiation effect will be excluded which occur only at high radiation doses and, as such, always cause damage which, in therapeutic application to cancer, may again be lifesaving. It should be emphasized that the article is limited to a greatly restricted range of biological effects of ionizing radiation which, consequently, are of limited value for overall assessment. (orig.) [de

  8. A Multiple-Channel Sub-Band Transient Detection System

    Energy Technology Data Exchange (ETDEWEB)

    David A. Smith

    1998-11-01

    We have developed a unique multiple-channel sub-band transient detection system to record transient electromagnetic signals in carrier-dominated radio environments; the system has been used to make unique observations of weak, transient HF signals. The detection system has made these observations possible through improved sensitivity compared to conventional broadband transient detection systems; the sensitivity improvement is estimated to be at least 20 dB. The increase in sensitivity has been achieved through subdivision of the band of interest (an 18 MHz tunable bandwidth) into eight sub-band independent detection channels, each with a 400 kHz bandwidth and its own criteria. The system generates a system trigger signal when a predetermined number of channels (typically five) trigger within a predetermined window of time (typically 100 ~s). Events are recorded with a broadband data acquisition system sampling at 50 or 100 Msample/s, so despite the fact that the detection system operates on portions of the signal confined to narrow bands, data acquisition is broadband. Between May and September of 1994, the system was used to detect and record over six thousand transient events in the frequency band from 3 to 30 MHz. Approximately 500 of the events have been characterized as paired bursts of radio noise with individual durations of 2 to 10 ps and separations between the bursts of 5 to 160 ps. The paired transients are typically 5 to 40 dB brighter than the background electromagnetic spectrum between carrier signals. We have termed these events SubIonospheric Pulse Pairs (SIPPS) and presently have no explanation as to their source. Our observations of SIPPS resemble observations of TransIonospheric Pulse Pairs (TIPPs) recorded by the Blackboard instrument on the ALEXIS satellite; the source of TIPP events is also unknown. Most of the recorded SIPP events do not exhibit frequency dispersion, implying propagation along a line-of-sight (groundwave) path; but seven of

  9. Simulating Precambrian banded iron formation diagenesis

    DEFF Research Database (Denmark)

    Posth, Nicole R.; K??hler, Inga; D. Swanner, Elizabeth

    2013-01-01

    Post-depositional diagenetic alteration makes the accurate interpretation of key precipitation processes in ancient sediments, such as Precambrian banded iron formations (BIFs), difficult. While microorganisms are proposed as key contributors to BIF deposition, the diagenetic transformation...

  10. The Novel Microwave Stop-Band Filter

    Directory of Open Access Journals (Sweden)

    R. E. Chernobrovkin

    2008-01-01

    Full Text Available The stop-band filter with the new band-rejection element is proposed. The element is a coaxial waveguide with the slot in the centre conductor. In the frame of this research, the numerical and experimental investigations of the amplitude-frequency characteristics of the filter are carried out. It is noted that according to the slot parameters the two typical resonances (half-wave and quarter-wave can be excited. The rejection band of the single element is defined by the width, depth, and dielectric filling of the slot. Fifth-order Chebyshev filter utilizing the aforementioned element is also synthesized, manufactured, and tested. The measured and simulated results are in good agreement. The experimental filter prototype exhibits the rejection band 0.86 GHz at the level −40 dB.

  11. Experimental study on the adiabatic shear bands

    International Nuclear Information System (INIS)

    Affouard, J.

    1984-07-01

    Four martensitic steels (Z50CDV5 steel, 28CND8 steel, 35NCDV16 steel and 4340 steel) with different hardness between 190 and 600 Hsub(B) (Brinell hardness), have been studied by means of dynamic compressive tests on split Hopkinson pressure bar. Microscopic observations show that the fracture are associated to the development of adiabatic shear bands (except 4340 steel with 190 Hsub(B) hardness). By means of tests for which the deformation is stopped at predetermined levels, the measurement of shear and hardness inside the band and the matrix indicates the chronology of this phenomenon: first the localization of shear, followed by the formation of adiabatic shear band and ultimatly crack initiation and propagation. These results correlated with few simulations by finite elements have permitted to suggest two mecanisms of deformation leading to the formation of adiabatic shear bands in this specific test [fr

  12. Microbiological processes in banded iron formation deposition

    DEFF Research Database (Denmark)

    Posth, Nicole R.; Konhauser, Kurt O.; Kappler, Andreas

    2013-01-01

    Banded iron formations have been studied for decades, particularly regarding their potential as archives of the Precambrian environment. In spite of this effort, the mechanism of their deposition and, specifically, the role that microbes played in the precipitation of banded iron formation minerals......, remains unresolved. Evidence of an anoxic Earth with only localized oxic areas until the Great Oxidation Event ca 2·45 to 2·32 Ga makes the investigation of O2-independent mechanisms for banded iron formation deposition relevant. Recent studies have explored the long-standing proposition that Archean...... banded iron formations may have been formed, and diagenetically modified, by anaerobic microbial metabolisms. These efforts encompass a wide array of approaches including isotope, ecophysiological and phylogeny studies, molecular and mineral marker analysis, and sedimentological reconstructions. Herein...

  13. Deployable Ka-Band Reflectarray, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Tyvak, in collaboration with UCLA, proposes a novel approach to the challenge of creating a large reflector for Ka-band high data rate links. We propose to attach...

  14. Full L-S Band Telemetry System

    National Research Council Canada - National Science Library

    Jensen, Michael

    2001-01-01

    Recent changes in spectrum availability as well as higher demands for spectrum have motivated the development of telemetry transmit systems capable of fully operating over both L and S telemetry bands...

  15. Full L-S Band Telemetry System

    National Research Council Canada - National Science Library

    Jensen, Michael

    2003-01-01

    Recent changes in spectrum availability as well as higher demands for spectrum have motivated the development of telemetry transmit systems capable of fully operating over both L and S telemetry bands...

  16. Full L-S Band Telemetry System

    National Research Council Canada - National Science Library

    Jensen, Michael

    2002-01-01

    Recent changes in spectrum availability as well as higher demands for spectrum have motivated the development of telemetry transmit systems capable of fully operating over both L and S telemetry bands...

  17. Confidence bands for inverse regression models

    International Nuclear Information System (INIS)

    Birke, Melanie; Bissantz, Nicolai; Holzmann, Hajo

    2010-01-01

    We construct uniform confidence bands for the regression function in inverse, homoscedastic regression models with convolution-type operators. Here, the convolution is between two non-periodic functions on the whole real line rather than between two periodic functions on a compact interval, since the former situation arguably arises more often in applications. First, following Bickel and Rosenblatt (1973 Ann. Stat. 1 1071–95) we construct asymptotic confidence bands which are based on strong approximations and on a limit theorem for the supremum of a stationary Gaussian process. Further, we propose bootstrap confidence bands based on the residual bootstrap and prove consistency of the bootstrap procedure. A simulation study shows that the bootstrap confidence bands perform reasonably well for moderate sample sizes. Finally, we apply our method to data from a gel electrophoresis experiment with genetically engineered neuronal receptor subunits incubated with rat brain extract

  18. Radiation safety

    International Nuclear Information System (INIS)

    1996-04-01

    Most of the ionizing radiation that people are exposed to in day-to-day activities comes from natural, rather than manmade, sources. The health effects of radiation - both natural and artificial - are relatively well understood and can be effectively minimized through careful safety measures and practices. The IAEA, together with other international and expert organizations, is helping to promote and institute Basic Safety Standards on an international basis to ensure that radiation sources and radioactive materials are managed for both maximum safety and human benefit

  19. Radiation physics

    International Nuclear Information System (INIS)

    Nam, Sang Hui

    1991-02-01

    This book deals with radiation physics, which introduces atomic theory and an atomic nucleus of materials, conception of an atom and materials, wave and particle, X ray generation and character, a radioactive element and change law, nature of radioactivity, neutron rays, fission, alpha collapse and beta collage and a neutrino collapse of artificial radioactivity such as collapse of artificial nucleus and artificial radioactivity and radiative capture, interaction with materials like interaction between a charged particle and materials and interaction among X-ray, r-ray and materials, radiation of quantity and unit and a charged particle accelerator.

  20. Synchrotron radiation

    CERN Document Server

    Kunz, C

    1974-01-01

    The production of synchrotron radiation as a by-product of circular high-energy electron (positron) accelerators or storage rings is briefly discussed. A listing of existing or planned synchrotron radiation laboratories is included. The following properties are discussed: spectrum, collimation, polarization, and intensity; a short comparison with other sources (lasers and X-ray tubes) is also given. The remainder of the paper describes the experimental installations at the Deutsches Elektronen-Synchrotron (DESY) and DORIS storage rings, presents a few typical examples out of the fields of atomic, molecular, and solid-state spectroscopy, and finishes with an outlook on the use of synchrotron radiation in molecular biology. (21 refs).

  1. Radiation dosimeter

    International Nuclear Information System (INIS)

    Fox, R.J.

    1983-01-01

    A radiation detector readout circuit is provided which produces a radiation dose-rate readout from a detector even though the detector output may be highly energy dependent. A linear charge amplifier including an output charge pump circuit amplifies the charge signal pulses from the detector and pumps the charge into a charge storage capacitor. The discharge rate of the capacitor through a resistor is controlled to provide a time-dependent voltage which when integrated provides an output proportional to the dose-rate of radiation detected by the detector. This output may be converted to digital form for readout on a digital display

  2. Circularly Polarized S Band Dual Frequency Square Patch Antenna Using Glass Microfiber Reinforced PTFE Composite

    Directory of Open Access Journals (Sweden)

    M. Samsuzzaman

    2014-01-01

    Full Text Available Circularly polarized (CP dual frequency cross-shaped slotted patch antenna on 1.575 mm thick glass microfiber reinforced polytetrafluoroethylene (PTFE composite material substrate is designed and fabricated for satellite applications. Asymmetric cross-shaped slots are embedded in the middle of the square patch for CP radiation and four hexagonal slots are etched on the four sides of the square patch for desired dual frequency. Different substrate materials have been analysed to achieve the desired operating band. The experimental results show that the impedance bandwidth is approximately 30 MHz (2.16 GHz to 2.19 GHz for lower band and 40 MHz (3.29 GHz to 3.33 GHz for higher band with an average peak gain of 6.59 dBiC and 5.52 dBiC, respectively. Several optimizations are performed to obtain the values of the antenna physical parameters. Moreover, the proposed antenna possesses compactness, light weight, simplicity, low cost, and circularly polarized. It is an attractive candidate for dual band satellite antennas where lower band can be used for uplink and upper band can be used for downlink.

  3. Dual Band Metamaterial Antenna For LTE/Bluetooth/WiMAX System.

    Science.gov (United States)

    Hasan, Md Mehedi; Faruque, Mohammad Rashed Iqbal; Islam, Mohammad Tariqul

    2018-01-19

    A compact metamaterial inspired antenna operate at LTE, Bluetooth and WiMAX frequency band is introduced in this paper. For the lower band, the design utilizes an outer square metallic strip forcing the patch to radiate as an equivalent magnetic-current loop. For the upper band, another magnetic current loop is created by adding metamaterial structure near the feed line on the patch. The metamaterial inspired antenna dimension of 42 × 32 mm 2 compatible to wireless devices. Finite integration technique based CST Microwave Studio simulator has been used to design and numerical investigation as well as lumped circuit model of the metamaterial antenna is explained with proper mathematical derivation. The achieved measured dual band operation of the conventional antenna are sequentially, 0.561~0.578 GHz, 2.346~2.906 GHz, and 2.91~3.49 GHz, whereas the metamaterial inspired antenna shows dual-band operation from 0.60~0.64 GHz, 2.67~3.40 GHz and 3.61~3.67 GHz, respectively. Therefore, the metamaterial antenna is applicable for LTE and WiMAX applications. Besides, the measured metamaterial antenna gains of 0.15~3.81 dBi and 3.47~3.75 dBi, respectively for the frequency band of 2.67~3.40 GHz and 3.61~3.67 GHz.

  4. Intraluminal penetration of the band in patients with adjustable silicone gastric banding: radiological findings

    Energy Technology Data Exchange (ETDEWEB)

    Pretolesi, F.; Derchi, L.E. [Cattedra di Radiologia R, Univ. di Genova (Italy); Camerini, G.; Gianetta, E.; Marinari, G.M.; Scopinaro, N. [Semeiotica Chirurgica R, Univ. di Genova (Italy)

    2001-03-01

    The aim of this study was to analyse radiological findings in patients surgically treated for adjustable silicone gastric banding (ASGB) for morbid obesity complicated by band penetration into the gastric lumen. We reviewed the records of four patients with surgically confirmed penetration of gastric band into the gastric lumen; three had preoperative opaque meal, one only a plain abdominal film. Vomiting was the presenting symptom in two cases, whereas others had new weight gain and loss of early satiety. Two patients had normally closed bands: radiography showed that their position had changed from previous controls and the barium meal had passed out of their lumen. Two patients had an open band. One patient had the band at the duodeno-jejunal junction, and the tube connecting the band to the subcutaneous port presented a winding course suggesting the duodenum. In the other case, both plain film and barium studies failed to demonstrate with certainty the intragastric position of the band. As ASGB is becoming widely used, radiologists need to be familiar with its appearances and its complications. Band penetration into the stomach is a serious complication which needs band removal. Patients with this problem, often with non-specific symptoms and even those who are asymptomatic, are encountered during radiographic examinations requested either for gastric problems or follow-up purposes, and have to be properly diagnosed. (orig.)

  5. C-band Scatterometers and Their Applications

    OpenAIRE

    Naeimi, Vahid; Wagner, Wolfgang

    2010-01-01

    C-band scatterometers have demonstrated to be valuable sensors for large-scale observation of the Earth's surface in a variety of disciplines. High temporal sampling in all weather conditions, multi-viewing capability and availability of long-term measurements make the European C-band scatterometers excellent Earth observation tools. Scatterometer data are used to extract geophysical parameters such as wind speed and direction, surface soil moisture, seasonal dynamics of vegetation, spatial a...

  6. Development of a sapphire fiber thermometer using two wavelength bands

    Science.gov (United States)

    Ye, Linhua; Shen, Yonghang

    1996-09-01

    This paper reports the development of a sapphire ((alpha) - Al2O3) single crystal optical fiber thermometer using two wavelength bands. A thin film of precious metal or ceramic deposited onto one end of the sapphire fiber forms a mini-radiation cavity. The other end of the sapphire fiber is coupled to a low-loss silica fiber. Radiation from the small cavity is transmitted along the silica fiber into a photodetection system which consists of a lens, beam splitter, two interference filters (820 nm and 940 nm center wavelength, 30 nm bandwidth) and two silicon photocells. The temperature measurement is based on the detection of radiation from the small cavity. The sapphire fiber (0.25 - 1.0 mm diameter, 100 - 450 mm length) was grown by the laser heated pedestal growth (LHPG) methods. Transmission loss in the sapphire fiber was experimentally measured. Theoretical analysis shows the apparent emittance of the small cavity with a length to diameter (L/D) ratio greater than eight is a constant value near to one, so the small cavity can be considered as a small black-body cavity. Using the developed sapphire fiber temperature sensor, we have built a sapphire fiber thermometer based on a 8098 single-chip microcomputer system. It was calibrated at some known stable temperature point and uses the fundamental radiation law to extrapolate to other temperatures. By taking the ratio of the optical power at two wavelengths, errors due to changes in the system, such as emissivity and transmission losses, can be canceled out. The thermometer has an operating temperature range of 800 to 1900 degrees Celsius, and an accuracy of 0.2% at 1000 degrees Celsius. There are a number of applications of the thermometer both in science and industry.

  7. Electron correlations in narrow band systems

    International Nuclear Information System (INIS)

    Kishore, R.

    1983-01-01

    The effect of the electron correlations in narrow bands, such as d(f) bands in the transition (rare earth) metals and their compounds and the impurity bands in doped semiconductors is studied. The narrow band systems is described, by the Hubbard Hamiltonian. By proposing a local self-energy for the interacting electron, it is found that the results are exact in both atomic and band limits and reduce to the Hartree Fock results for U/Δ → 0, where U is the intra-atomic Coulomb interaction and Δ is the bandwidth of the noninteracting electrons. For the Lorentzian form of the density of states of the noninteracting electrons, this approximation turns out to be equivalent to the third Hubbard approximation. A simple argument, based on the mean free path obtained from the imaginary part of the self energy, shows how the electron correlations can give rise to a discontinous metal-nonmetal transition as proposed by Mott. The band narrowing and the existence of the satellite below the Fermi energy in Ni, found in photoemission experiments, can also be understood. (Author) [pt

  8. Free electron laser with terahertz band Bragg reflectors

    Directory of Open Access Journals (Sweden)

    Naum S. Ginzburg

    2009-06-01

    Full Text Available Periodical Bragg structures may be considered as an effective way of controlling the electromagnetic energy fluxes and provision of spatially coherent radiation in the free electron lasers with oversized interaction space. A new scheme of terahertz band FEL with hybrid Bragg resonator is proposed consisting of advanced input Bragg mirror and traditional output Bragg mirror. An advanced Bragg mirror exploiting the coupling between the two counterpropagating modes and the quasicutoff one provides mode selection over the transverse index. The main amplification of the wave by the electron beam takes place in the regular section of the resonator. Small reflections from the output traditional Bragg mirror are sufficient for oscillator self-excitation.

  9. Radiating confidence

    International Nuclear Information System (INIS)

    Rush, P.

    1988-01-01

    Radiation monitoring systems for operators handling radioactive wastes are described. These include a personnel monitoring system which is suitable for small groups (ie as few as 50) of personnel. The use of microelectronics enable facilities such as automatic personal dose recording with three accumulative registers and automatic reporting of exceeded dose limits. At a controlled entrance the user is identified with a personal identification number. Exit is then also monitored. The use of pocket dosimeters increase the flexibility of this system. In another system a 'rotary man lock' only allows exit from the radiation controlled zone when satisfactory radiation checks have been made. The radiation and security checks available with this system are described. A 'sack monitor' for low level wastes contained in plastic bags is illustrated. (U.K.)

  10. Radiation curing

    International Nuclear Information System (INIS)

    Wendrinsky, J.

    1987-04-01

    In the beginning of the seventies the two types of radiation sources applied in industrial processes, electron radiation and UV, had been given rather optimistic forecasts. While UV could succeed in the field of panel and film coating, electron radiation curing seems to gain success in quite new fields of manufacturing. The listing of the suggested applications of radiation curing and a comparison of both advantages and disadvantages of this technology are followed by a number of case studies emphasizing the features of these processes and giving some examplary calculations. The data used for the calculations should provide an easy calculation of individual manufacturing costs if special production parameters, investment or energy costs are employed. (Author)

  11. Synchrotron Radiation

    International Nuclear Information System (INIS)

    Asfour, F.I

    2000-01-01

    Synchrotron light is produced by electron accelerators combined with storage rings. This light is generated over a wide spectral region; from infra-red (IR) through the visible and vacuum ultraviolet (VUV), and into the X-ray region. For relativistic electrons (moving nearly with the speed of light), most radiation is concentrated in a small cone with an opening angle of 1/gamma(some 0.1 to 1 milliradian),where gamma is the electron energy in units of rest energy (typically 10 3 -10 4 ). In synchrotron radiation sources (storage rings) highly relativistic electrons are stored to travel along a circular path for many hours. Radiation is caused by transverse acceleration due to magnetic forces(bending magnets). The radiation is emitted in pulses of 10-20 picosecond, separated by some 2 nanosecond or longer separation

  12. Infrared radiation

    International Nuclear Information System (INIS)

    Moss, C.E.; Ellis, R.J.; Murray, W.E.; Parr, W.H.

    1989-01-01

    All people are exposed to IR radiation from sunlight, artificial light and radiant heating. Exposures to IR are quantified by irradiance and radiant exposure to characterize biological effects on the skin and cornea. However, near-IR exposure to the retina requires knowledge of the radiance of the IR source. With most IR sources in everyday use the health risks are considered minimal; only in certain high radiant work environments are individuals exposed to excessive levels. The interaction of IR radiation with biological tissues is mainly thermal. IR radiation may augment the biological response to other agents. The major health hazards are thermal injury to the eye and skin, including corneal burns from far-IR, heat stress, and retinal and lenticular injury from near-IR radiation. 59 refs, 13 figs, 2 tabs

  13. Radiation shield

    International Nuclear Information System (INIS)

    Hosoya, Yasuaki

    1993-01-01

    In the present invention, the thickness of the radiation shields is minimized to save the quantity of shields thereby utilizing spaces in a facility effectively. That is, the radiation shields of the present invention comprise first and second shields forming stepwise gaps. They are disposed between a high dose region and a low dose region. The first and second shields have a feature in that the thickness thereof can be set to a size capable of shielding the gaps in accordance with the strength of the radiation source to be shielded. With such a constitution, the thickness of the shields of the radiation processing facility can be minimized. Accordingly, the quantity of the shields can be greatly saved. Spaces in the facility can be utilized effectively. (I.S.)

  14. Synchrotron radiation

    International Nuclear Information System (INIS)

    Helliwell, J.R.; Walker, R.P.

    1985-01-01

    A detailed account of the research work associated with the Synchrotron Radiation Source at Daresbury Laboratory, United Kingdom, in 1984/85, is presented in the Appendix to the Laboratory's Annual Report. (U.K.)

  15. Radiation sickness

    Science.gov (United States)

    ... GO About MedlinePlus Site Map FAQs Customer Support Health Topics Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Radiation sickness URL of this page: //medlineplus.gov/ency/article/ ...

  16. Radiation damage

    CERN Document Server

    Heijne, Erik H M; CERN. Geneva

    1998-01-01

    a) Radiation damage in organic materials. This series of lectures will give an overview of radiation effects on materials and components frequently used in accelerator engineering and experiments. Basic degradation phenomena will be presented for organic materials with comprehensive damage threshold doses for commonly used rubbers, thermoplastics, thermosets and composite materials. Some indications will be given for glass, scintillators and optical fibres. b) Radiation effects in semiconductor materials and devices. The major part of the time will be devoted to treat radiation effects in semiconductor sensors and the associated electronics, in particular displacement damage, interface and single event phenomena. Evaluation methods and practical aspects will be shown. Strategies will be developed for the survival of the materials under the expected environmental conditions of the LHC machine and detectors. I will describe profound revolution in our understanding of black holes and their relation to quantum me...

  17. Radiation sensors

    International Nuclear Information System (INIS)

    Wykes, J.S.; Adsley, I.

    1981-01-01

    Radiation detectors, suitable for use in industrial environments, eg coal mines are claimed. At least two scintillation crystals are mounted on a resilient support material, preferably silicone rubber. The sensors are both robust and compact. (U.K.)

  18. Radiation safety

    International Nuclear Information System (INIS)

    Goetz, B.B.; Murphy, C.H.

    1987-01-01

    In medicine, as in other fields of scientific endeavor, the development of advanced and specialized techniques has resulted in increased hazards for employees. However, by possessing both an appreciation of the proper use of factors that regulate radiation exposure around radiology equipment and a knowledge of the biologic effects of radiation, which can include possible genetic and somatic consequences, it is possible to maximize the usefulness of these valuable procedures while minimizing the risk to medical personnel involved with patient care

  19. Radiation Transport

    Energy Technology Data Exchange (ETDEWEB)

    Urbatsch, Todd James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-06-15

    We present an overview of radiation transport, covering terminology, blackbody raditation, opacities, Boltzmann transport theory, approximations to the transport equation. Next we introduce several transport methods. We present a section on Caseology, observing transport boundary layers. We briefly broach topics of software development, including verification and validation, and we close with a section on high energy-density experiments that highlight and support radiation transport.

  20. Synchrotron radiation

    International Nuclear Information System (INIS)

    Norman, D.; Walker, R.P.; Durham, P.J.; Ridley, P.A.

    1986-01-01

    The paper on synchrotron radiation is the appendix to the Daresbury (United Kingdom) annual report, 1985/86. The bulk of the volume is made up of the progress reports for the work carried out during the year under review using the Synchrotron Radiation Source (SRS) at Daresbury. The Appendix also contains: the scientific programmes at the the SRS, progress on beamlines, instrumentation and computing developments, and activities connected with accelerator development. (U.K.)

  1. Radiation protection

    International Nuclear Information System (INIS)

    Koelzer, W.

    1976-01-01

    The lecture is divided into five sections. The introduction deals with the physical and radiological terms, quantities and units. Then the basic principles of radiological protection are discussed. In the third section attention is paid to the biological effects of ionizing radiation. The fourth section deals with the objectives of practical radiological protection. Finally the emergency measures are discussed to be taken in radiation accidents. (HP) [de

  2. Synchrotron radiation

    International Nuclear Information System (INIS)

    Poole, M.W.; Lea, K.R.

    1982-01-01

    A report is given on the work involving the Synchrotron Radiation Division of the Daresbury Laboratory during the period January 1981 - March 1982. Development of the source, beamlines and experimental stations is described. Progress reports from individual investigators are presented which reveal the general diversity and interdisciplinary nature of the research which benefits from access to synchrotron radiation and the associated facilities. Information is given on the organisation of the Division and publications written by the staff are listed. (U.K.)

  3. Radiation Protection

    International Nuclear Information System (INIS)

    Loos, M.

    2001-01-01

    Major achievements of SCK-CEN's Radiation Protection Department in 2000 are described. The main areas for R and D of the department remain neutron dosimetry and neutron activation analysis, safeguards information handling and non-destructive assay techniques. Further activities include low-level radioactivity measurements in environmental and biological samples and radiation protection research. Finally, achievements in decision strategy research and social sciences in nuclear research are reported

  4. Multi-band Microwave Antennas and Devices based on Generalized Negative-Refractive-Index Transmission Lines

    Science.gov (United States)

    Ryan, Colan Graeme Matthew

    Focused on the quad-band generalized negative-refractive-index transmission line (G-NRI-TL), this thesis presents a variety of novel printed G-NRI-TL multi-band microwave device and antenna prototypes. A dual-band coupled-line coupler, an all-pass G-NRI-TL bridged-T circuit, a dual-band metamaterial leaky-wave antenna, and a multi-band G-NRI-TL resonant antenna are all new developments resulting from this research. In addition, to continue the theme of multi-band components, negative-refractive-index transmission lines are used to create a dual-band circularly polarized transparent patch antenna and a two-element wideband decoupled meander antenna system. High coupling over two independently-specified frequency bands is the hallmark of the G-NRI-TL coupler: it is 0.35lambda0 long but achieves approximately -3 dB coupling over both bands with a maximum insertion loss of 1 dB. This represents greater design flexibility than conventional coupled-line couplers and less loss than subsequent G-NRI-TL couplers. The single-ended bridged-T G-NRI-TL offers a metamaterial unit cell with an all-pass magnitude response up to 8 GHz, while still preserving the quad-band phase response of the original circuit. It is shown how the all-pass response leads to wider bandwidths and improved matching in quad-band inverters, power dividers, and hybrid couplers. The dual-band metamaterial leaky-wave antenna presented here was the first to be reported in the literature, and it allows broadside radiation at both 2 GHz and 6 GHz without experiencing the broadside stopband common to conventional periodic antennas. Likewise, the G-NRI-TL resonant antenna is the first reported instance of such a device, achieving quad-band operation between 2.5 GHz and 5.6 GHz, with a minimum radiation efficiency of 80%. Negative-refractive-index transmission line loading is applied to two devices: an NRI-TL meander antenna achieves a measured 52% impedance bandwidth, while a square patch antenna incorporates

  5. A 3D Convective Model for the Jovian Wind Bands

    Science.gov (United States)

    Mayr, H. G.; Chan, K. L.

    2004-01-01

    In an earlier paper, we proposed that Jupiter's alternating wind bands are a manifestation of the global interaction between rotation and convection in a shallow layer. The model, however, was obtained from linearization of the 2D equations of motions. At HKUST/Hong Kong, we are now trying to study this problem by rigorous numerical simulation. Using a three-dimensional spectral numerical code, we compute models for the outermost layer of Jupiter's convective envelope. Two cases have been studied. In one the atmospheric pressure varies from 1 to 23 bar, and in the other from 1 to 115 bar. The physical parameters (internal energy flux, rotation rate) are chosen to be close to those expected, but solar heating, chemistry, as well as dynamical influences from deeper layers are ignored. The models generate wind field patterns that contain alternating jet streams with resemblance to the Jovian bands. Instantaneous values of the mean zonal flow at the equator reach 80 m/sec. Yet the mean meridional flows are less than 1% of such value. The meridional temperature profile at the cloud top level also shows a double hump structure of a few degrees (as observed) in the subtropics. Though there is not complete quantitative agreement (caused perhaps by neglected effects like solar radiation), these models demonstrate, in principle, the feasibility of generating a Jovian type wind pattern through the interaction of fast rotation and convection in a thin shell.

  6. ISM band to U-NII band frequency transverter and method of frequency transversion

    Science.gov (United States)

    Stepp, Jeffrey David [Grandview, MO; Hensley, Dale [Grandview, MO

    2006-09-12

    A frequency transverter (10) and method for enabling bi-frequency dual-directional transfer of digitally encoded data on an RF carrier by translating between a crowded or otherwise undesirable first frequency band, such as the 2.4 GHz ISM band, and a less-crowded or otherwise desirable second frequency band, such as the 5.0 GHz 6.0 GHz U-NII band. In a preferred embodiment, the transverter (10) connects between an existing data radio (11) and its existing antenna (30), and comprises a bandswitch (12); an input RF isolating device (14); a transmuter (16); a converter (18); a dual output local oscillator (20); an output RF isolating device (22); and an antenna (24) tuned to the second frequency band. The bandswitch (12) allows for bypassing the transverter (10), thereby facilitating its use with legacy systems. The transmuter (14) and converter (16) are adapted to convert to and from, respectively, the second frequency band.

  7. Effects of band-tails on the subthreshold characteristics of nanowire band-to-band tunneling transistors

    Science.gov (United States)

    Khayer, M. Abul; Lake, Roger K.

    2011-10-01

    High source doping is required to support the high electric fields necessary to provide sufficient drive currents in interband tunnel field effect transistors (TFETs). High doping is associated with band-tails in the density of states that decay exponentially into the bandgap with decay constants that can be comparable to the room temperature thermal energy kBT. This compromises the core operational principal of a TFET of a hard energy cut-off to the injected channel carrier distribution provided by the source valence band edge. If the band-tails are limited to the source region, they have minimal effect for short channels ≤10 nm, since the leakage current is dominated by direct, coherent tunneling through the channel. For longer 20 nm channels, source band-tails can double the inverse subthreshold slope but still leave it below the ideal 60 mV/decade value with on-off current ratios greater than 106 using a supply voltage of 0.4 V. Band-tails both in the source and channel are more detrimental for both 10 and 20 nm channels. On-off current ratios are reduced to ≥103 and ≥104 for the 10 nm and 20 nm channel devices, respectively.

  8. Mapping Forest Cover and Forest Cover Change with Airborne S-Band Radar

    Directory of Open Access Journals (Sweden)

    Ramesh K. Ningthoujam

    2016-07-01

    Full Text Available Assessments of forest cover, forest carbon stocks and carbon emissions from deforestation and degradation are increasingly important components of sustainable resource management, for combating biodiversity loss and in climate mitigation policies. Satellite remote sensing provides the only means for mapping global forest cover regularly. However, forest classification with optical data is limited by its insensitivity to three-dimensional canopy structure and cloud cover obscuring many forest regions. Synthetic Aperture Radar (SAR sensors are increasingly being used to mitigate these problems, mainly in the L-, C- and X-band domains of the electromagnetic spectrum. S-band has not been systematically studied for this purpose. In anticipation of the British built NovaSAR-S satellite mission, this study evaluates the benefits of polarimetric S-band SAR for forest characterisation. The Michigan Microwave Canopy Scattering (MIMICS-I radiative transfer model is utilised to understand the scattering mechanisms in forest canopies at S-band. The MIMICS-I model reveals strong S-band backscatter sensitivity to the forest canopy in comparison to soil characteristics across all polarisations and incidence angles. Airborne S-band SAR imagery over the temperate mixed forest of Savernake Forest in southern England is analysed for its information content. Based on the modelling results, S-band HH- and VV-polarisation radar backscatter and the Radar Forest Degradation Index (RFDI are used in a forest/non-forest Maximum Likelihood classification at a spatial resolution of 6 m (70% overall accuracy, κ = 0.41 and 20 m (63% overall accuracy, κ = 0.27. The conclusion is that S-band SAR such as from NovaSAR-S is likely to be suitable for monitoring forest cover and its changes.

  9. Performance characteristics of a perforated shadow band under clear sky conditions

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Michael J. [School of Mechanical Engineering, University of KwaZulu-Natal, Durban (South Africa)

    2010-12-15

    A perforated, non-rotating shadow band is described for separating global solar irradiance into its diffuse and direct normal components using a single pyranometer. Whereas shadow bands are normally solid so as to occult the sensor of a pyranometer throughout the day, the proposed band has apertures cut from its circumference to intermittently expose the instrument sensor at preset intervals. Under clear sky conditions the device produces a saw tooth waveform of irradiance data from which it is possible to reconstruct separate global and diffuse curves. The direct normal irradiance may then be calculated giving a complete breakdown of the irradiance curves without need of a second instrument or rotating shadow band. This paper describes the principle of operation of the band and gives a mathematical model of its shading mask based on the results of an optical ray tracing study. An algorithm for processing the data from the perforated band system is described and evaluated. In an extended trial conducted at NREL's Solar Radiation Research Laboratory, the band coupled with a thermally corrected Eppley PSP produced independent curves for diffuse, global and direct normal irradiance with low mean bias errors of 5.6 W/m{sup 2}, 0.3 W/m{sup 2} and -2.6 W/m{sup 2} respectively, relative to collocated reference instruments. Random uncertainties were 9.7 W/m{sup 2} (diffuse), 17.3 W/m{sup 2} (global) and 19.0 W/m{sup 2} (direct). When the data processing algorithm was modified to include the ray trace model of sensor exposure, uncertainties increased only marginally, confirming the effectiveness of the model. Deployment of the perforated band system can potentially increase the accuracy of data from ground stations in predominantly sunny areas where instrumentation is limited to a single pyranometer. (author)

  10. Brain radiation - discharge

    Science.gov (United States)

    Radiation - brain - discharge; Cancer-brain radiation; Lymphoma - brain radiation; Leukemia - brain radiation ... Decadron) while you are getting radiation to the brain. It may make you hungrier, cause leg swelling ...

  11. Investigation of Patch Antenna Based on Photonic Band-Gap Substrate with Heterostructures

    Directory of Open Access Journals (Sweden)

    Zhenghua Li

    2012-01-01

    Full Text Available The characteristics of the patch antenna based on photonic band-gap (PBG substrate with heterostructures were studied numerically by using the method of finite difference time domain (FDTD. The results indicate that, comparing to the conventional patch antennas, the expansion of working frequency band of the new patch antenna can be realized and its radiation efficiency also can be improved notably with the influence of PBG. In addition, for this new kind of patch antenna, its return loss is much less and there are two minimum values for return loss corresponding to the resonant frequency of the two different photonic crystals made of the substrate. Its physical mechanism lies on the PBG which suppresses the surface waves propagating along the surface of the substrate and reflects most of electromagnetic wave energy radiated to the substrate significantly.

  12. Design of Compact Flower Shape Dual Notched-Band Monopole Antenna for Extended UWB Wireless Applications

    Science.gov (United States)

    Sharma, Manish; Awasthi, Y. K.; Singh, Himanshu; Kumar, Raj; Kumari, Sarita

    2016-11-01

    In this letter, a compact monopole antenna for ultra wideband (UWB) applications is proposed with small size of 18×20=360 mm2. Antenna consist of a flower shape radiating patch with a pair of C-shaped slots which offer two notch bands for WiMAX (3.04-3.68 GHz) & WLAN (4.73-5.76 GHz) and two rectangular shaped slots in the ground plane which provides a wide measured usable fractional extended bandwidth of 163 % (2.83-14.0 GHz) with improved VSWR. Moreover, it is also convenient for other wireless application as close range radar, 8-12 GHz in X-band. Measured radiation patterns exhibits nearly omnidirectional in H-plane and dipole like pattern in E-plane across the bandwidth and furthermore exhibits good time domain performance.

  13. Dual band multi frequency rectangular patch microstrip antenna with flyswatter shaped slot for wireless systems

    Energy Technology Data Exchange (ETDEWEB)

    Bhardwaj, Dheeraj, E-mail: dbhardwaj.bit@gmail.com [Department of Physics, BIT-Mesra-Jaipur Campus, Jaipur 302017 (India); Saraswat, Shriti, E-mail: saraswat.srishti@gmail.com; Gulati, Gitansh, E-mail: gitanshgulati@gmail.com; Shekhar, Snehanshu, E-mail: snehanshushekhar.bit@gmail.com; Joshi, Kanika, E-mail: kanika.karesh@gmail.com [Department of Electronics & Communication, BIT-Mesra-Jaipur Campus, Jaipur 302017 (India); Sharma, Komal, E-mail: kbhardwaj18@gmail.com [Department of Physics, Swami Keshvanand Institute of Technology, Jaipur 302017 (India)

    2016-03-09

    In this paper a dual band planar antenna has been proposed for IEEE 802.16 Wi-MAX /IEEE 802.11 WLAN/4.9 GHz public safety applications. The antenna comprises a frequency bandwidth of 560MHz (3.37GHz-3.93GHz) for WLAN and WiMAX and 372MHz (4.82GHz-5.192GHz) for 4.9 GHz public safety applications and Radio astronomy services (4.8-4.94 GHz). The proposed antenna constitutes of a single microstrip patch reactively loaded with three identical steps positioned in a zig-zag manner towards the radiating edges of the patch. The coaxially fed patch antenna characteristics (radiation pattern, antenna gain, antenna directivity, current distribution, S{sub 11}) have been investigated. The antenna design is primarily focused on achieving a dual band operation.

  14. Dual band multi frequency rectangular patch microstrip antenna with flyswatter shaped slot for wireless systems

    International Nuclear Information System (INIS)

    Bhardwaj, Dheeraj; Saraswat, Shriti; Gulati, Gitansh; Shekhar, Snehanshu; Joshi, Kanika; Sharma, Komal

    2016-01-01

    In this paper a dual band planar antenna has been proposed for IEEE 802.16 Wi-MAX /IEEE 802.11 WLAN/4.9 GHz public safety applications. The antenna comprises a frequency bandwidth of 560MHz (3.37GHz-3.93GHz) for WLAN and WiMAX and 372MHz (4.82GHz-5.192GHz) for 4.9 GHz public safety applications and Radio astronomy services (4.8-4.94 GHz). The proposed antenna constitutes of a single microstrip patch reactively loaded with three identical steps positioned in a zig-zag manner towards the radiating edges of the patch. The coaxially fed patch antenna characteristics (radiation pattern, antenna gain, antenna directivity, current distribution, S 11 ) have been investigated. The antenna design is primarily focused on achieving a dual band operation.

  15. Dual band multi frequency rectangular patch microstrip antenna with flyswatter shaped slot for wireless systems

    Science.gov (United States)

    Bhardwaj, Dheeraj; Saraswat, Shriti; Gulati, Gitansh; Shekhar, Snehanshu; Joshi, Kanika; Sharma, Komal

    2016-03-01

    In this paper a dual band planar antenna has been proposed for IEEE 802.16 Wi-MAX /IEEE 802.11 WLAN/4.9 GHz public safety applications. The antenna comprises a frequency bandwidth of 560MHz (3.37GHz-3.93GHz) for WLAN and WiMAX and 372MHz (4.82GHz-5.192GHz) for 4.9 GHz public safety applications and Radio astronomy services (4.8-4.94 GHz). The proposed antenna constitutes of a single microstrip patch reactively loaded with three identical steps positioned in a zig-zag manner towards the radiating edges of the patch. The coaxially fed patch antenna characteristics (radiation pattern, antenna gain, antenna directivity, current distribution, S11) have been investigated. The antenna design is primarily focused on achieving a dual band operation.

  16. A Novel CPW-Fed UWB Antenna with Band-Stop Function

    Directory of Open Access Journals (Sweden)

    Huaming Chen

    2014-01-01

    Full Text Available A novel coplanar waveguide-fed (CPW ultrawideband (UWB antenna with band-stop function is presented in this paper. The proposed antenna comprises a CPW-fed slot rectangular patch with an open stub ground plane, and two inverted L-shaped strip conductors are fabricated on the back plane. The overall size of the antenna is 25 × 25 × 1.6 mm2, and it achieves good impedance matching and radiation gain. Simulated and measured results show that the designed antenna operates at 2.9 GHz–13.08 GHz with band rejection in the frequency band of 7.7 GHz–9.05 GHz for satellite applications, and the proposed antenna is suitable for UWB wireless communication applications.

  17. Triple-Notched Band CPW fed UWB Antenna with Metallic Reflector for High Gain Performance

    Directory of Open Access Journals (Sweden)

    K. G. Jangid

    2017-10-01

    Full Text Available This paper exhibits the design and performance of a coplanar waveguide (CPW fed triple notched band ultra-wide band (UWB antenna. Proposed prototype has two U-shaped slots on the patch and an inverted U slot in feed line with a metal reflector beneath the radiating element. Proposed structure renders wider impedance bandwidth extended between frequencies 2.71GHz to 12.92 GHz for VSWR 2. The utmost simulated gain of proposed antenna with reflector is close to 9.9dBi at 7.4GHz. A sharp reduction observed in the efficiency values of the proposed structure at stop bands. Perhaps, this structure proved as a useful tool for various applications in modern communication systems including UWB.

  18. Two-Step Beveled UWB Printed Monopole Antenna with Band Notch

    Directory of Open Access Journals (Sweden)

    Yan Xiao

    2014-01-01

    Full Text Available This paper presents a novel compact printed monopole ultra-wideband (UWB antenna featured with the band notch. The proposed antenna consists of a two-step beveled radiant patch and a truncated ground plane, which can provide a good impedance matching from 3.1 GHz to 10.6 GHz. In order to generate the band-notched characteristics, two symmetrical slots are embedded along with the microstrip feeding line, resulting in a band notch from 5.05 GHz to 5.85 GHz. Accordingly, the mutual electromagnetic interference between the UWB and wireless local area network (WLAN radio communication systems can be eliminated. In addition, it is shown how the slots integrated on the ground plane improve the radiation patterns. The experimental measurements are found to be in good agreement with the numerical simulations.

  19. Compact monopole-like slot antenna and band-notched design for ultrawideband applications

    Science.gov (United States)

    Qing, Xianming; Chen, Zhi Ning

    2009-04-01

    A compact monopole-like slot antenna and its extended band-notched design are presented for ultrawideband (UWB) applications. The proposed antenna is etched on a printed circuit board and fed by a microstrip fork-shaped feeding stub. The characteristics of the proposed antenna are investigated numerically and validated experimentally. The prototype with an overall size of 25 mm × 25 mm × 0.8 mm achieves good impedance matching, constant gain, stable radiation patterns, and consistent group delay over an operating bandwidth of 3.0-12.9 GHz (124.5%). In addition, the proposed antenna features less ground plane dependence. By adding two grounded open-circuited stubs, the proposed antenna features band-notched characteristics at 5-6 GHz while it maintains the desirable performance over lower/upper UWB bands of 3.1-4.8 GHz/6.2-9.7 GHz.

  20. Compact Dual-Band Dipole Antenna with Asymmetric Arms for WLAN Applications

    Directory of Open Access Journals (Sweden)

    Chung-Hsiu Chiu

    2014-01-01

    Full Text Available A dual-band dipole antenna that consists of a horn- and a C-shaped metallic arm is presented. Depending on the asymmetric arms, the antenna provides two −10 dB impedance bandwidths of 225 MHz (about 9.2% at 2.45 GHz and 1190 MHz (about 21.6% at 5.5 GHz, respectively. This feature enables it to cover the required bandwidths for wireless local area network (WLAN operation at the 2.4 GHz band and 5.2/5.8 GHz bands for IEEE 802.11 a/b/g standards. More importantly, the compact size (7 mm × 24 mm and good radiating performance of the antenna are profitable to be integrated with wireless communication devices on restricted RF-elements spaces.

  1. Tri Band Dual Polarized Patch Antenna System For Next Generation Cellular Networks

    Directory of Open Access Journals (Sweden)

    Syed Daniyal Ali Shah

    2017-12-01

    Full Text Available In fifth generation networks much emphasis is given to reduce the handset and base station sizes while incorporating even more features for ubiquitous connectivity. Polarization diversity is one of the methods in which a single multi-polarized antenna brings the advantages of antenna diversity. The multiband handset antennas can be made dual-polarized for improved compensation of fading effects of propagation environment especially in terrestrial bands. This paper focuses on the outcomes of the development of a horizontal and vertical polarized patch antenna scheme that operates on 3 bands 900 MHz 1.8 GHz and 2.4 GHz. The antenna system is tested for gain directivity reflection loss polarization radiation pattern and other parameters. The results are published and found are found to satisfy the requirements of cellular and data communication networks in the specified bands.

  2. Parasitic-Element-Loaded UWB Antenna with Band-Stop Function for Mobile Handset Wireless USB

    Directory of Open Access Journals (Sweden)

    Yohan Lim

    2012-01-01

    Full Text Available A UWB antenna loaded by parasitic elements for wireless USB of mobile handsets is proposed for UWB service in which a band-stop function of 5.725–5.825 GHz WLAN band is required. Two kinds of parasitic elements are incorporated into a rectangular radiator to obtain enhanced impedance bandwidth and band-stop function. The proposed antenna is very compact in size. Wide bandwidths of 3.15–4.75 GHz and 7.2–10.2 GHz are achieved while 5.725–5.825 GHz is notched. Three different shapes of conventional mobile terminals are also considered for measurement.

  3. The Development of Layered Photonic Band Gap Structures Using a Micro-Transfer Molding Technique

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, Kevin Jerome [Iowa State Univ., Ames, IA (United States)

    2001-01-01

    Photonic band gap (PBG) crystals are periodic dielectric structures that manipulate electromagnetic radiation in a manner similar to semiconductor devices manipulating electrons. Whereas a semiconductor material exhibits an electronic band gap in which electrons cannot exist, similarly, a photonic crystal containing a photonic band gap does not allow the propagation of specific frequencies of electromagnetic radiation. This phenomenon results from the destructive Bragg diffraction interference that a wave propagating at a specific frequency will experience because of the periodic change in dielectric permitivity. This gives rise to a variety of optical applications for improving the efficiency and effectiveness of opto-electronic devices. These applications are reviewed later. Several methods are currently used to fabricate photonic crystals, which are also discussed in detail. This research involves a layer-by-layer micro-transfer molding ({mu}TM) and stacking method to create three-dimensional FCC structures of epoxy or titania. The structures, once reduced significantly in size can be infiltrated with an organic gain media and stacked on a semiconductor to improve the efficiency of an electronically pumped light-emitting diode. Photonic band gap structures have been proven to effectively create a band gap for certain frequencies of electro-magnetic radiation in the microwave and near-infrared ranges. The objective of this research project was originally two-fold: to fabricate a three dimensional (3-D) structure of a size scaled to prohibit electromagnetic propagation within the visible wavelength range, and then to characterize that structure using laser dye emission spectra. As a master mold has not yet been developed for the micro transfer molding technique in the visible range, the research was limited to scaling down the length scale as much as possible with the current available technology and characterizing these structures with other methods.

  4. Total Ionizing Dose Test Report BFR92A NPN 5 GHz Wide Band Transistor from NXP

    Science.gov (United States)

    Phan, Anthony M.; Oldham, Timothy R.

    2011-01-01

    The purpose of this test was to characterize the Philips/NXP BFR92A NPN 5 gigahertz wide band silicon transistor for total dose response. This test shall serves as the radiation lot acceptance test (RLAT) for the lot date code (LDC) 1027. The BFR92A is packaged in a 3-pin plastic SOT23 package. Low dose rate (LDR/ELDRS) irradiations was performed.

  5. Automated coregistration of MTI spectral bands.

    Energy Technology Data Exchange (ETDEWEB)

    Theiler, J. P. (James P.); Galbraith, A. E. (Amy E.); Pope, P. A. (Paul A.); Ramsey, K. A. (Keri A.); Szymanski, J. J. (John J.)

    2002-01-01

    In the focal plane of a pushbroom imager, a linear array of pixels is scanned across the scene, building up the image one row at a time. For the Multispectral Thermal Imager (MTI), each of fifteen different spectral bands has its own linear array. These arrays are pushed across the scene together, but since each band's array is at a different position on the focal plane, a separate image is produced for each band. The standard MTI data products resample these separate images to a common grid and produce coregistered multispectral image cubes. The coregistration software employs a direct 'dead reckoning' approach. Every pixel in the calibrated image is mapped to an absolute position on the surface of the earth, and these are resampled to produce an undistorted coregistered image of the scene. To do this requires extensive information regarding the satellite position and pointing as a function of time, the precise configuration of the focal plane, and the distortion due to the optics. These must be combined with knowledge about the position and altitude of the target on the rotating ellipsoidal earth. We will discuss the direct approach to MTI coregistration, as well as more recent attempts to 'tweak' the precision of the band-to-band registration using correlations in the imagery itself.

  6. Excited negative parity bands in 160Yb

    Science.gov (United States)

    Saha, A.; Bhattacharjee, T.; Curien, D.; Dedes, I.; Mazurek, K.; Banerjee, S. R.; Rajbanshi, S.; Bisoi, A.; de Angelis, G.; Bhattacharya, Soumik; Bhattacharyya, S.; Biswas, S.; Chakraborty, A.; Das Gupta, S.; Dey, B.; Goswami, A.; Mondal, D.; Pandit, D.; Palit, R.; Roy, T.; Singh, R. P.; Saha Sarkar, M.; Saha, S.; Sethi, J.

    2018-03-01

    Negative parity rotational bands in {} 70160Yb{}90 nucleus have been studied. They were populated in the 148Sm(16O, 4n)160Yb reaction at 90 MeV. The gamma-coincidence data have been collected using Indian National Gamma Array composed of twenty Compton suppressed clover germanium (Ge) detectors. Double gating on triple gamma coincidence data were selectively used to develop the decay scheme for these negative parity bands by identifying and taking care of the multiplet transitions. The even- and odd-spin negative parity bands in 160Yb have been studied by comparing the reduced transition probability ratios with the similar bands in neighbouring even-even rare earth nuclei. It is concluded that the concerned odd-spin and even-spin bands are not signature partners and that their structures are compatible with those of the ‘pear-shape’ and ‘pyramid-shape’ oscillations, respectively, the octupole shapes superposed with the quadrupole shape of the ground-state.

  7. Mesoscopic colonization of a spectral band

    International Nuclear Information System (INIS)

    Bertola, M; Lee, S Y; Mo, M Y

    2009-01-01

    We consider the unitary matrix model in the limit where the size of the matrices becomes infinite and in the critical situation when a new spectral band is about to emerge. In previous works, the number of expected eigenvalues in the neighborhood of the band was fixed and finite, a situation that was termed 'birth of a cut' or 'first colonization'. We now consider the transitional regime where this microscopic population in the new band grows without bounds but at a slower rate than the size of the matrix. The local population in the new band organizes in a 'mesoscopic' regime, in between the macroscopic behavior of the full system and the previously studied microscopic one. The mesoscopic colony may form a finite number of new bands, with a maximum number dictated by the degree of criticality of the original potential. We describe the delicate scaling limit that realizes and controls the mesoscopic colony. The method we use is the steepest descent analysis of the Riemann-Hilbert problem that is satisfied by the associated orthogonal polynomials.

  8. Percutaneous tension band wiring for patellar fractures.

    Science.gov (United States)

    Rathi, Akhilesh; Swamy, M K S; Prasantha, I; Consul, Ashu; Bansal, Abhishek; Bahl, Vibhu

    2012-08-01

    To evaluate outcome of percutaneous tension band wiring for transverse fractures of the patella. 16 men and 7 women aged 27 to 65 (mean, 40) years underwent percutaneous tension band wiring for transverse fractures of the patella with a displacement of >3 mm. Pain, operating time, mobility, functional score, and complications were evaluated. 20 patients underwent successful percutaneous tension band wiring. The remaining 3 patients in whom closed reduction failed underwent open reduction and tension band wiring. The mean operating time was 46 (range, 28-62) minutes. The mean follow-up period was 20 (range, 15-30) months. At the latest follow-up, all patients had regained full extension. The objective score was excellent in 20 patients and good in 3, whereas the subjective score was excellent in 17, good in 5, and fair in one. All patients had radiological union at week 8. One patient had patellofemoral arthritis (secondary to a postoperative articular step). Two patients developed superficial infections, which resolved after antibiotic therapy. Mean thigh muscle wasting was 0.7 (range, 0.4-1) cm. Three patients encountered hardware problems (impingement/irritation of the skin over the knee) necessitating implant removal. Percutaneous tension band wiring is a viable option for transverse fractures of the patella.

  9. Ferritin associates with marginal band microtubules

    International Nuclear Information System (INIS)

    Infante, Anthony A.; Infante, Dzintra; Chan, M.-C.; How, P.-C.; Kutschera, Waltraud; Linhartova, Irena; Muellner, Ernst W.; Wiche, Gerhard; Propst, Friedrich

    2007-01-01

    We characterized chicken erythrocyte and human platelet ferritin by biochemical studies and immunofluorescence. Erythrocyte ferritin was found to be a homopolymer of H-ferritin subunits, resistant to proteinase K digestion, heat stable, and contained iron. In mature chicken erythrocytes and human platelets, ferritin was localized at the marginal band, a ring-shaped peripheral microtubule bundle, and displayed properties of bona fide microtubule-associated proteins such as tau. Red blood cell ferritin association with the marginal band was confirmed by temperature-induced disassembly-reassembly of microtubules. During erythrocyte differentiation, ferritin co-localized with coalescing microtubules during marginal band formation. In addition, ferritin was found in the nuclei of mature erythrocytes, but was not detectable in those of bone marrow erythrocyte precursors. These results suggest that ferritin has a function in marginal band formation and possibly in protection of the marginal band from damaging effects of reactive oxygen species by sequestering iron in the mature erythrocyte. Moreover, our data suggest that ferritin and syncolin, a previously identified erythrocyte microtubule-associated protein, are identical. Nuclear ferritin might contribute to transcriptional silencing or, alternatively, constitute a ferritin reservoir

  10. The dilemma of the wedding band.

    Science.gov (United States)

    Stein, Daniel T; Pankovich-Wargula, Alanna L

    2009-02-01

    The postoperative infection rate in procedures where no ring is worn, and those where a plain metal wedding band is worn under the glove was studied retrospectively. From January 1998 through June 2002, 2127 surgeries were performed by the lead author (D.T.S.), the first 2 years without a wedding band and the next 2 years with a simple platinum wedding band worn under the glove. Attention was paid to sliding the ring proximal and distal on the finger, ensuring scrub solution was under the ring and that the area of skin below the ring was cleansed. Twenty-two postoperative infections were recorded in 2127 surgeries. This is a postoperative infection rate of 1.0%, and wedding ring worn, nor do they demonstrate an increased infection rate with wearing jewelry. This study suggests that there is no correlation between wearing a plain wedding band under the surgical glove and an increase in postoperative infections. The crevices and cuticle of the fingers and nails may provide more significant infection risk than a plain metal wedding band. This is a level III retrospective cohort study.

  11. Band warping, band non-parabolicity, and Dirac points in electronic and lattice structures

    Science.gov (United States)

    Resca, Lorenzo; Mecholsky, Nicholas A.; Pegg, Ian L.

    2017-10-01

    We illustrate at a fundamental level the physical and mathematical origins of band warping and band non-parabolicity in electronic and vibrational structures. We point out a robust presence of pairs of topologically induced Dirac points in a primitive-rectangular lattice using a p-type tight-binding approximation. We analyze two-dimensional primitive-rectangular and square Bravais lattices with implications that are expected to generalize to more complex structures. Band warping is shown to arise at the onset of a singular transition to a crystal lattice with a larger symmetry group, which allows the possibility of irreducible representations of higher dimensions, hence band degeneracy, at special symmetry points in reciprocal space. Band warping is incompatible with a multi-dimensional Taylor series expansion, whereas band non-parabolicities are associated with multi-dimensional Taylor series expansions to all orders. Still band non-parabolicities may merge into band warping at the onset of a larger symmetry group. Remarkably, while still maintaining a clear connection with that merging, band non-parabolicities may produce pairs of conical intersections at relatively low-symmetry points. Apparently, such conical intersections are robustly maintained by global topology requirements, rather than any local symmetry protection. For two p-type tight-binding bands, we find such pairs of conical intersections drifting along the edges of restricted Brillouin zones of primitive-rectangular Bravais lattices as lattice constants vary relatively to each other, until these conical intersections merge into degenerate warped bands at high-symmetry points at the onset of a square lattice. The conical intersections that we found appear to have similar topological characteristics as Dirac points extensively studied in graphene and other topological insulators, even though our conical intersections have none of the symmetry complexity and protection afforded by the latter more

  12. Analysis of X-Band Link Performance Degradation Caused by Adjacent Satellite

    Science.gov (United States)

    Park, Durk-Jong; Ahn, Sang-Il; Chun, Yong-Sik; Chun, Yong-Sik

    2011-12-01

    As more satellites are designed to downlink their observed image data through the X-band frequency band, it is inevitable that the occupied bandwidth of a target satellite will overlap with that of other X-band downlink satellites. For sun-synchronized low earth orbit satellites, in particular, it can be expected that two or more satellites be placed within the looking angle of a ground station antenna at the same time. Due to the overlapping in the frequency band, signals transmitted from the adjacent satellites act as interferers, leading to degraded link performance between target satellite and ground station. In this paper, link analysis was initiated by modeling the radiation pattern of ground station antenna through a validated Jet Propulsion Laboratory peak envelope model. From the relative antenna gain depending on the offset angle from center axis of maximum antenna directivity, the ratio of received interference signal level to the target signal level was calculated. As a result, it was found that the degradation increased when the offset angle was within the first null point of radiation pattern. For a 7.3 m antenna, serious link degradation began at an offset angle of 0.4 degrees. From this analysis, the link performance of the coming satellite passes can be recognized, which is helpful to establish an operating procedure that will prevent the ground station from receiving corrupted image data in the event of a degraded link.

  13. Novel Dual Band Microstrip Circular Patch Antennas Loaded with ENG and MNG Metamaterials

    Directory of Open Access Journals (Sweden)

    Md. Ababil Hossain

    2014-01-01

    Full Text Available Novel design of a dual band microstrip circular patch antenna loaded with ENG (ε negative metamaterial has been shown in the first section. Using ENG metamaterial instead of the conventional dielectric, unconventional TMδ10 (1<δ<2 mode was produced to yield a dual band performance. Optimized parameters such as permittivity (ε1 and filling ratio (η of metamaterials were selected with the aid of a MATLAB based parameter optimization algorithm, developed for all these sort of patch antennas. In the second section, a dual band circular patch antenna loaded with MNG (µ negative metamaterial has been reported. An unconventional modified TMδ10 (0<δ<1 mode has been produced along with conventional TM110 mode due to using MNG metamaterial. Here also the optimum values of permeability (µ1 and filling ratio (η for these sorts of patch antennas have been calculated from a MATLAB based parameter optimization algorithm. Both the proposed antennas provide good and resonance and satisfactory radiation performances (directivity, radiation efficiency, and gain with a dual band performance.

  14. Comparison of EEG and MEG in source localization of induced human gamma-band oscillations during visual stimulus.

    Science.gov (United States)

    Mideksa, K G; Hoogenboom, N; Hellriegel, H; Krause, H; Schnitzler, A; Deuschl, G; Raethjen, J; Heute, U; Muthuraman, M

    2015-08-01

    High frequency gamma oscillations are indications of information processing in cortical neuronal networks. Recently, non-invasive detection of these oscillations have become one of the main research areas in magnetoencephalography (MEG) and electroencephalography (EEG) studies. The aim of this study, which is a continuation of our previous MEG study, is to compare the capability of the two modalities (EEG and MEG) in localizing the source of the induced gamma activity due to a visual stimulus, using a spatial filtering technique known as dynamic imaging of coherent sources (DICS). To do this, the brain activity was recorded using simultaneous MEG and EEG measurement and the data were analyzed with respect to time, frequency, and location of the strongest response. The spherical head modeling technique, such as, the three-shell concentric spheres and an overlapping sphere (local sphere) have been used as a forward model to calculate the external electromagnetic potentials and fields recorded by the EEG and MEG, respectively. Our results from the time-frequency analysis, at the sensor level, revealed that the parieto-occipital electrodes and sensors from both modalities showed a clear and sustained gamma-band activity throughout the post-stimulus duration and that both modalities showed similar strongest gamma-band peaks. It was difficult to interpret the spatial pattern of the gamma-band oscillatory response on the scalp, at the sensor level, for both modalities. However, the source analysis result revealed that MEG3 sensor type, which measure the derivative along the longitude, showed the source more focally and close to the visual cortex (cuneus) as compared to that of the EEG.

  15. A High-Speed Power-Line Communication System with Band-Limited OQAM Based Multi-Carrier Transmission

    Science.gov (United States)

    Kawabata, Naohiro; Koga, Hisao; Muta, Osamu; Akaiwa, Yoshihiko

    As a method to realize a high-speed communication in the home network, the power-line communication (PLC) technique is known. A problem of PLC is that leakage radiation interferes with existing systems. When OFDM is used in a PLC system, the leakage radiation is not sufficiently reduced, even if the subcarriers corresponding to the frequency-band of the existing system are never used, because the signal is not strictly band-limited. To solve this problem, each subcarrier must be band-limited. In this paper, we apply the OQAM based multi-carrier transmission (OQAM-MCT) to a high-speed PLC system, where each subcarrier is individually band-limited. We also propose a pilot-symbol sequence suitable for frequency offset estimation, symbol-timing detection and channel estimation in the OQAM-MCT system. In this method, the pilot signal-sequence consists of a repeated series of the same data symbol. With this method, the pilot sequence approximately becomes equivalent to OFDM sequence and therefore existing pilot-assisted methods for OFDM are also applicable to OQAM-MCT system. Computer simulation results show that the OQAM-MCT system achieves both good transmission rate performance and low out-of-band radiation in PLC channels. It is also shown that the proposed pilot-sequence improves frequency offset estimation, symbol-timing detection and channel estimation performance as compared with the case of using pseudo-noise sequence.

  16. Directional radiation detectors

    Science.gov (United States)

    Dowell, Jonathan L.

    2017-09-12

    Directional radiation detectors and systems, methods, and computer-readable media for using directional radiation detectors to locate a radiation source are provided herein. A directional radiation detector includes a radiation sensor. A radiation attenuator partially surrounds the radiation sensor and defines an aperture through which incident radiation is received by the radiation sensor. The aperture is positioned such that when incident radiation is received directly through the aperture and by the radiation sensor, a source of the incident radiation is located within a solid angle defined by the aperture. The radiation sensor senses at least one of alpha particles, beta particles, gamma particles, or neutrons.

  17. Simplicial band depth for multivariate functional data

    KAUST Repository

    López-Pintado, Sara

    2014-03-05

    We propose notions of simplicial band depth for multivariate functional data that extend the univariate functional band depth. The proposed simplicial band depths provide simple and natural criteria to measure the centrality of a trajectory within a sample of curves. Based on these depths, a sample of multivariate curves can be ordered from the center outward and order statistics can be defined. Properties of the proposed depths, such as invariance and consistency, can be established. A simulation study shows the robustness of this new definition of depth and the advantages of using a multivariate depth versus the marginal depths for detecting outliers. Real data examples from growth curves and signature data are used to illustrate the performance and usefulness of the proposed depths. © 2014 Springer-Verlag Berlin Heidelberg.

  18. Tidal radiation

    International Nuclear Information System (INIS)

    Mashhoon, B.

    1977-01-01

    The general theory of tides is developed within the framework of Einstein's theory of gravitation. It is based on the concept of Fermi frame and the associated notion of tidal frame along an open curve in spacetime. Following the previous work of the author an approximate scheme for the evaluation of tidal gravitational radiation is presented which is valid for weak gravitational fields. The emission of gravitational radiation from a body in the field of a black hole is discussed, and for some cases of astrophysical interest estimates are given for the contributions of radiation due to center-of-mass motion, purely tidal deformation, and the interference between the center of mass and tidal motions

  19. Ionizing radiations

    International Nuclear Information System (INIS)

    2009-01-01

    After having recalled some fundamental notions and measurement units related to ionizing radiations, this document describes various aspects of natural and occupational exposures: exposure modes and sources, exposure levels, biological effects, health impacts. Then, it presents prevention principles aimed at, in an occupational context of use of radiation sources (nuclear industry excluded), reducing and managing these exposures: risk assessment, implementation of safety from the front end. Some practical cases illustrate the radiation protection approach. The legal and regulatory framework is presented: general notions, worker exposure, measures specific to some worker categories (pregnant and breast feeding women, young workers, temporary workers). A last part describes what is to be done in case of incident or accident (dissemination of radioactive substances from unsealed sources, anomaly occurring when using a generator or a sealed source, post-accident situation)

  20. Ionising radiation

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The law covering ionising radiations in Belgium is summarised under the headings: the outline law of 19 March 1958; the General Regulation for the protection of the population and workers against the danger of ionising radiation (introduction; application; the control of classified establishments; organisation of general protection; importation, transit and distribution of radioactive substances; transport of radioactive substances; nuclear propulsion; ionising radiation in human or veterinary medicine; prohibitions and authorisations; exceptional measures; monitoring of the national territory and of the population as a whole; the approval of experts, organisations and doctors; monitoring; the public company for the management of radioactive waste and fissile materials); the law of 4 August 1955 concerning state security in the field of nuclear energy; civil responsibility; the Interministerial Commission on Nuclear Safety and State Security in the Nuclear Field; the non-proliferation of nuclear arms. (U.K.)

  1. Radiation sensor

    International Nuclear Information System (INIS)

    Brown, W.L.; Geronime, R.L.

    1977-01-01

    Radiation sensor and thermocouple, respectively, which can be used for reactor in-core instrumentation. The radiation sensor consists of an inconel conductor wire and rhodium emitter wire, the thermocouple of two intertwined alumel or chromel wires. Both are arranged in the center of a metal tube relative to which they are separated by an insulator made of SiO 2 fibers. This insulator is first introduced as a loose fabric between the radiation sensor and the thermocouple, respectively, and the metal tube and then compacted to a density of 35-73% of pure SiO 2 by drawing the tube. There is no need for soldering or welding. The insulation resistivity at room temperature ist between 10 14 and 10 15 ohms. (ORU) [de

  2. Radiofrequency radiation

    International Nuclear Information System (INIS)

    Elder, J.A.; Czerski, P.A.; Stuchly, M.A.; Mild, K.H.; Sheppard, A.R.

    1989-01-01

    High-level radiofrequency radiation is a source of thermal energy that carries all of the known implications of heating for biological systems, including burns, temporary and permanent changes in reproduction, cataracts, and death. In general, no changes in chromosomes, DNA or the reproductive potential of animals exposed to RF radiation have been reported in the absence of significant rises in temperature, though there are limited data on DNA and chromosomal changes at non-thermal levels. Human data are currently limited and do not provide adequate information about the relationship between prolonged low-level RF radiation exposure and increased mortality or morbidity, including cancer incidence. In epidemiological studies and clinical reports of RF effects in man, the problems of quantification are numerous and include uncertainties about ''dose'', health effects, latent periods, dose-response relationships, and interactions with other physical or chemical agents. 228 refs, 6 figs, 2 tabs

  3. Cherenkov radiation

    International Nuclear Information System (INIS)

    Hubert, P.

    1955-01-01

    When the radioactivity has been discovered, it was observed by researchers that different materials as mineral salts or solutions were emitting a weak light when submitted to radioactivity beams. At the beginning it has been thought that it was fluorescent light. In 1934, Cherenkov, a russian physicist, worked on the luminescence of uranyl salts solutions caused by gamma radiation and observed a very weak light was emitted by pure liquid. After further studies, he concluded that this phenomena was different from fluorescence. Since then, it has been called Cherenkov effect. This blue light emission is produced when charged particles are going through a transparent medium with an upper velocity than light velocity. This can happen only in medium with large refractive index as water or glass. It also presents its different properties discovered afterwards. The different applications of the Cherenkov radiation are discussed as counting techniques for radiation detectors or comic ray detectors. (M.P.)

  4. Band Edge Dynamics and Multiexciton Generation in Narrow Band Gap HgTe Nanocrystals.

    Science.gov (United States)

    Livache, Clément; Goubet, Nicolas; Martinez, Bertille; Jagtap, Amardeep; Qu, Junling; Ithurria, Sandrine; Silly, Mathieu G; Dubertret, Benoit; Lhuillier, Emmanuel

    2018-04-02

    Mercury chalcogenide nanocrystals and especially HgTe appear as an interesting platform for the design of low cost mid-infrared (mid-IR) detectors. Nevertheless, their electronic structure and transport properties remain poorly understood, and some critical aspects such as the carrier relaxation dynamics at the band edge have been pushed under the rug. Some of the previous reports on dynamics are setup-limited, and all of them have been obtained using photon energy far above the band edge. These observations raise two main questions: (i) what are the carrier dynamics at the band edge and (ii) should we expect some additional effect (multiexciton generation (MEG)) as such narrow band gap materials are excited far above the band edge? To answer these questions, we developed a high-bandwidth setup that allows us to understand and compare the carrier dynamics resonantly pumped at the band edge in the mid-IR and far above the band edge. We demonstrate that fast (>50 MHz) photoresponse can be obtained even in the mid-IR and that MEG is occurring in HgTe nanocrystal arrays with a threshold around 3 times the band edge energy. Furthermore, the photoresponse can be effectively tuned in magnitude and sign using a phototransistor configuration.

  5. Fuzzy Riesz subspaces, fuzzy ideals, fuzzy bands and fuzzy band projections

    OpenAIRE

    Hong, Liang

    2015-01-01

    Fuzzy ordered linear spaces, Riesz spaces, fuzzy Archimedean spaces and $\\sigma$-complete fuzzy Riesz spaces were defined and studied in several works. Following the efforts along this line, we define fuzzy Riesz subspaces, fuzzy ideals, fuzzy bands and fuzzy band projections and establish their fundamental properties.

  6. Band-gap and band-edge engineering of multicomponent garnet scintillators from first principles

    Czech Academy of Sciences Publication Activity Database

    Yadav, S.K.; Uberuaga, B.P.; Nikl, Martin; Jiang, C.; Stanek, C.R.

    2015-01-01

    Roč. 4, č. 5 (2015), "054012-1"-"054012-9" ISSN 2331-7019 R&D Projects: GA ČR GAP204/12/0805 Institutional support: RVO:68378271 Keywords : scintillator * electronic band gap structure * garnets * band gap engineering Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.061, year: 2015

  7. Radiation control

    International Nuclear Information System (INIS)

    Uchida, Akira

    1981-01-01

    This paper describes on how the condition of radiation level in the ring (storage ring) experimentation room changes corresponding to the operating stage of SOR-ring (synchrotron radiation storage ring), and does not describe on the present radiation control in the SOR facility. The operating stage of SOR is divided into the following five: (1) 307 MeV electron injection, (2) 307 MeV electron storage (used for SOR experiments), (3) energy increase from 307 to 380 MeV, (4) 380 MeV electron storage, (5) re-injection and completion of operation. Gamma and X ray levels are shown when electron beam is injected from the electron synchrotron to the SOR-ring. Two main causes of the high level are reported. Spatial dose rate in storing 307 MeV electrons in also illustrated. This is sufficiently lower than that at electron incidence. The measurement of radiation level at the time of energy increase from 307 to 380 MeV has just started. Since the radiation level in 380 MeV storage, measured at the points about 20 cm apart from the electron orbit, showed several mR/h, the level seems to be negligible at the points where experiments are carried out, 1 m away from the measurement points. The radiation level in electron reinjection and completion of operation may be large during a short period (a few Roentgen) like the time of energy increase. Therefore, the beam shall be re-injected or decreased after confirming that all experimenters have retreated into the predetermined place. (Wakatsuki, Y.)

  8. Radiation risks

    International Nuclear Information System (INIS)

    1991-01-01

    This report contains an evaluation of data available about the deleterious effects of exposure of people to ionising radiation, assuming that the total exposure is low (low dose) or that exposure to dose takes place gradually (low dose rate). It is a revision of the 1985 Health Council report on 'The scientific foundations for radiation protection policy based on the UNSCEAR-77, -82, and BEIR reports'. The report is also meant to be a reply to a request for advice made by the Minister of Welfare, Public Health and Culture in 1989. Scientific opinion on induction of cancer by radiation has clearly changed since 1988. This is a consequence of new publications of epidemiological studies among survivors of the atomic explosions of Hiroshima and Nagasaki. The Committee that has produced the present report has paid much attention to this development. Besides, in the request for advice just mentioned it is asked whether the margins of uncertainty which complicated the quantitative assessment of the radiation risk can be reduced. Consequently the Committee has dealt extensively with the potential errors and uncertainties in available data. Especially these 2 elements - a careful consideration of a recent shift in scientific opinion and a constant attention for the magnitude of potential uncertainties - have had a predominant influence on the content and design of this report. The Committee has tried to answer as fully as possible the complex question how to transform results of scientific research into a well-organised data set on which the government can base its radiation protection policy. The Committee had also compared its evaluation to the recent recommendations of the International Commission on Radiological Protection (ICRP) and the points of view of the Dutch policy directive 'Dealing with radiation risks'. (author). 111 refs.; 12 tabs

  9. 10Gb/s Ultra-Wideband Wireless Transmission Based on Multi-Band Carrierless Amplitude Phase Modulation

    DEFF Research Database (Denmark)

    Puerta Ramírez, Rafael; Rommel, Simon; Vegas Olmos, Juan José

    2016-01-01

    In this paper, for the first time, a record UWB transmission of 10Gb/s is experimentally demonstrated employing a multi-band approach of carrierless amplitude phase modulation (MultiCAP). The proposed solution complies with the restrictions on the effective radiated power established by both the ...

  10. Phase and frequency structure of superradiance pulses generated by relativistic Ka-band backward-wave oscillator

    International Nuclear Information System (INIS)

    Rostov, V. V.; Romanchenko, I. V.; Elchaninov, A. A.; Sharypov, K. A.; Shunailov, S. A.; Ul'masculov, M. R.; Yalandin, M. I.

    2016-01-01

    Phase and frequency stability of electromagnetic oscillations in sub-gigawatt superradiance (SR) pulses generated by an extensive slow-wave structure of a relativistic Ka-band backward-wave oscillator were experimentally investigated. Data on the frequency tuning and radiation phase stability of SR pulses with a variation of the energy and current of electron beam were obtained.

  11. 10Gb/s Ultra-Wideband Wireless Transmission Based on Multi-Band Carrierless Amplitude Phase Modulation

    DEFF Research Database (Denmark)

    Puerta Ramírez, Rafael; Rommel, Simon; Vegas Olmos, Juan José

    2016-01-01

    In this paper, for the first time, a record UWB transmission of 10Gb/s is experimentally demonstrated employing a multi-band approach of carrierless amplitude phase modulation (MultiCAP). The proposed solution complies with the restrictions on the effective radiated power established by both...

  12. Beam-Steerable Multi-Band Mm-Wave Bow-Tie Antenna Array for Mobile Terminals

    DEFF Research Database (Denmark)

    Rodriguez Cano, Rocio; Zhang, Shuai; Pedersen, Gert F.

    2018-01-01

    A multiple-band 5G end-fire antenna array is proposed to be placed on the upper and bottom edges of mobile terminals. The antenna element consists of two bow-tie radiators designed to resonate at 28 and 60 GHz. A sixteen-element beam-steerable array is presented in this paper, with overall dimens...

  13. Implementation and Investigation of a Compact Circular Wide Slot UWB Antenna with Dual Notched Band Characteristics using Stepped Impedance Resonators

    Directory of Open Access Journals (Sweden)

    Yingsong Li

    2012-04-01

    Full Text Available A coplanar waveguide (CPW fed ultra-wideband (UWB antenna with dual notched band characteristics is presented in this paper. The circular wide slot and circular radiation patch are utilized to broaden the impedance bandwidth of the UWB antenna. The dual notched band functions are achieved by employing two stepped impedance resonators (SIRs which etched on the circular radiation patch and CPW excitation line, respectively. The two notched bands can be controlled by adjusting the dimensions of the two stepped impedance resonators which give tunable notched band functions. The proposed dual notched band UWB antenna has been designed in details and optimized by means of HFSS. Experimental and numerical results show that the proposed antenna with compact size of 32 × 24 mm2, has an impedance bandwidth range from 2.8 GHz to 13.5 Hz for voltage standing-wave ratio (VSWR less than 2, except the notch bands 5.0 GHz - 6.2 GHz for HIPERLAN/2 and IEEE 802.11a (5.1 GHz - 5.9 GHz and 8.0 GHz - 9.3 GHz for satellite and military applications.

  14. Indirect Band Gap Emission by Hot Electron Injection in Metal/MoS2 and Metal/WSe2 Heterojunctions

    Science.gov (United States)

    Li, Zhen; Ezhilarasu, Goutham; Chatzakis, Ioannis; Dhall, Rohan; Chen, Chun-Chung; Cronin, Stephen

    Transition metal dichalcogenides (TMDCs), such as MoS2 and WSe2, are free of dangling bonds, therefore make more `ideal' Schottky junctions than bulk semiconductors, which produce recombination centers at the interface with metals, inhibiting charge transfer. Here, we observe a more than 10X enhancement in the indirect band gap PL of TMDCs deposited on various metals, while the direct band gap emission remains unchanged. We believe the main mechanism of light emission arises from photoexcited hot electrons in the metal that are injected into the conduction band of MoS2 and WSe2, and subsequently recombine radiatively with minority holes. Since the conduction band at the K-point is 0.5eV higher than at the Σ-point, a lower Schottky barrier of the Σ-point band makes electron injection more favorable. Also, the Σ band consists of the sulfur pz orbital, which overlaps more significantly with the electron wavefunctions in the metal. This enhancement only occurs for thick flakes, and is absent in monolayer and few-layer flakes. Here, the flake thickness must exceed the depletion width of the Schottky junction, in order for efficient radiative recombination to occur in the TMDC. The intensity of this indirect peak decreases at low temperatures. Reference: DOI: 10.1021/acs.nanolett.5b00885

  15. Dual-Band Dual-Mode Button Antenna for On-Body and Off-Body Communications.

    Science.gov (United States)

    Zhang, Xiu Yin; Wong, Hang; Mo, Te; Cao, Yun Fei

    2017-08-01

    A dual-band dual-mode button antenna for body centric communications is presented. At the lower band, a spiral inverted-F antenna is designed with omnidirectional radiation pattern for on-body communication. At the upper band, the high-order mode of the inverted-F antenna is utilized together with a metal reflector to realize broadside radiation for off-body communication. For demonstration, a prototype is implemented. The measured peak gains on the phantom at the lower and upper bands are -0.6 and 4.3 dBi, respectively. The antenna operating on the phantom has measured efficiencies of 46.3% at the lower band and 69.3% at the upper band. The issue of specific absorption rate (SAR) is studied. The maximum transmitted power under the SAR regulation of 1.6 W/kg is found to be 26.4 dB·m, which is high enough for body centric communications. In addition, the transmission performance between two proposed antennas mounted on the body is investigated by measuring the transmission loss. With an overall miniaturized size, the robust button antenna could be integrated in clothes and be a potential candidate for wireless body area network applications.

  16. Radiation dermatitis

    Energy Technology Data Exchange (ETDEWEB)

    Shack, R.B.; Lynch, J.B.

    1987-04-01

    Even in this era of modern radiotherapy, injuries associated with the medical and industrial use of radiation devices will continue to pose a difficult problem for the reconstructive surgeon. It must be borne in mind that the single most serious hazard to surgery in irradiated tissue is the lodgement of bacteria in tissue rendered avascular by the radiation and the secondary necrosis from the infection itself. The basic principles of wound management must be augmented by thorough knowledge of the use of well-vascularized muscle and musculocutaneous flap to provide adequate, blood-rich, soft-tissue coverage.

  17. Radiation physics

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    The radiation physics program is directed toward understanding the basic mechanism by which charged particles lose energy in traversing matter, and presenting this information in a way meaningful to the study of radiation dosimetry and biological damage. Measurements of the absolute cross sections for the ejection of electrons from ionization by fast charged particles, measurements of optical fluorescence from liquid systems, preliminary analyses of electron emission cross sections for proton bombardment of carbon foils, and nonexponential decay of fluorescence in both polar and nonpolar solutions are covered

  18. Radiation toxicology

    International Nuclear Information System (INIS)

    Fry, R.J.M.; Storer, J.B.; Ullrich, R.L.

    1979-01-01

    Extensive studies on both human and experimental animal populations have provided information that allow radiation protection standards to be set with greater confidence than for most if not all other carcinogenic agents. Furthermore, both international and national advisory bodies are continually updating the risk estimates and the standards as new information is available. However, it is clear that models are needed that take into account the multistage nature of carcinogenesis. Studies in both ionizing and ultraviolet radiation carcinogenesis are more valuable to the general problem of elucidating the mechanisms involved in cancer than is indicated by the amount of work or support for this field of research

  19. Radiation toxicology

    International Nuclear Information System (INIS)

    Fry, R.J.M.; Storer, J.B.; Ullrich, R.L.

    1979-01-01

    The extensive studies on both human and experimental animal populations have provided information that allows radiation protection standards to be set with greater confidence than for most if not all other carcinogenic agents. Furthermore, both international and national advisory bodies are continually updating the risk estimates and the standards as new information is available. However, it is clear that we need models that take into account the multistage nature of carcinogenesis. Studies in both ionizing and ultraviolet radiation carcinogenesis are more valuable to the general problem of elucidating the mechanisms involved in cancer than is indicated by the amount of work or support for this field of research

  20. Electron currents associated with an auroral band

    Science.gov (United States)

    Spiger, R. J.; Anderson, H. R.

    1975-01-01

    Measurements of electron pitch angle distributions and energy spectra over a broad auroral band were used to calculate net electric current carried by auroral electrons in the vicinity of the band. The particle energy spectrometers were carried by a Nike-Tomahawk rocket launched from Poker Flat, Alaska, at 0722 UT on February 25, 1972. Data are presented which indicate the existence of upward field-aligned currents of electrons in the energy range 0.5-20 keV. The spatial relationship of these currents to visual structure of the auroral arc and the characteristics of the electrons carrying the currents are discussed.

  1. Itinerant ferromagnetism in the narrow band limit

    CERN Document Server

    Liu, S H

    2000-01-01

    It is shown that in the narrow band, strong interaction limit the paramagnetic state of an itinerant ferromagnet is described by the disordered local moment state. As a result, the Curie temperature is orders of magnitude lower than what is expected from the large exchange splitting of the spin bands. An approximate analysis has also been carried out for the partially ordered state, and the result explains the temperature evolvement of the magnetic contributions to the resistivity and low-energy optical conductivity of CrO sub 2.

  2. Banding of connection standards for distributed generation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-05-04

    This report presents the views of distributed network operators (DNOs), developers, equipment manufacturers and consultants on the current banding of distributed generation in terms of connection standards and recommendations. The Documents ER G59/1, ER G75/1, ER G83/1 and ETR 113/1 covering recommendations for the connection of embedded generating plant to distribution systems and guidance notes for the protection of embedded generating plant are examined. The way in which the recommendations are applied in practice is investigated. Multiple distribution generator installations, fault ride through, and banding are considered as well as both protection required and maximum generator sizes at respective voltage levels.

  3. Band theory of metals the elements

    CERN Document Server

    Altmann, Simon L

    1970-01-01

    Band Theory of Metals: The Elements focuses on the band theory of solids. The book first discusses revision of quantum mechanics. Topics include Heisenberg's uncertainty principle, normalization, stationary states, wave and group velocities, mean values, and variational method. The text takes a look at the free-electron theory of metals, including heat capacities, density of states, Fermi energy, core and metal electrons, and eigenfunctions in three dimensions. The book also reviews the effects of crystal fields in one dimension. The eigenfunctions of the translations; symmetry operations of t

  4. Proximal iliotibial band syndrome: case report

    Directory of Open Access Journals (Sweden)

    Guilherme Guadagnini Falotico

    2013-08-01

    Full Text Available OBJECTIVE: The overuse injuries in the hip joint occur commonly in sports practitioners and currently due to technical advances in diagnostic imaging, especially magnetic resonance imaging (MRI, are often misdiagnosed. Recently, a group of people were reported, all female, with pain and swelling in the pelvic region.T2-weighted MRI showed increased signal in the enthesis of the iliotibial band (ITB along the lower border of the iliac tubercle. We report a case of a 34 year old woman, non-professional runner, with pain at the iliac crest with no history of trauma and whose MRI was compatible with the proximal iliotibial band syndrome.

  5. Ka-band waveguide rotary joint

    KAUST Repository

    Yevdokymov, Anatoliy

    2013-04-11

    The authors present a design of a waveguide rotary joint operating in Ka-band with central frequency of 33 GHz, which also acts as an antenna mount. The main unit consists of two flanges with a clearance between them; one of the flanges has three circular choke grooves. Utilisation of three choke grooves allows larger operating clearance. Two prototypes of the rotary joint have been manufactured and experimentally studied. The observed loss is from 0.4 to 0.8 dB in 1.5 GHz band.

  6. Radiology of vertical-banded gastroplasty

    International Nuclear Information System (INIS)

    Leekam, R.N.; Deitel, M.; Shankar, L.; Salsberg, B.B.

    1987-01-01

    Vertical banded gastroplasty is the most frequently performed operation for the treatment of morbid obesity. More than 550 such procedures have been done at our hospital over the past 4 years. This presentation describes the postoperative radiographic findings in many of these patients. Normal and abnormal appearances on plain films and on contrast agent-enhanced examinations are discussed. The authors found it useful to divide abnormal findings into three groups: abnormalities of the partition, abnormalities of the banded channel, and ulcers and extragastric leaks

  7. Strategic high-altitude atmospheric radiation code (SHARC) user instructions. Technical report, September 1987-January 1989

    Energy Technology Data Exchange (ETDEWEB)

    Sundberg, R.L.; Duff, J.W.; Bernstein, L.S.; Acharya, P.K.; Gruninger, J.H.

    1989-02-03

    This report describes how to implement and use the Strategic High-Altitude Radiance Code (SHARC). SHARC calculates atmospheric radiation for paths from 60 to 300 km altitude in the 2-40 micrometer spectral region. It models radiation due to NLTE (Non-Local Thermodynamic Equilibrium) molecular emissions which are the dominant sources at these altitudes. This initial version of SHARC includes the five strongest IR radiators, CO/sub 2/, NO, O/sub 3/, H/sub 2/O, and CO. The code is available on magnetic tape and can be obtained by written request to AFGL/OPB.

  8. The Strategic High-Altitude Atmospheric Radiation Code (SHARC) user instructions

    Science.gov (United States)

    Sundberg, R. L.; Duff, J. W.; Bernstein, L. S.; Acharya, P. K.; Gruninger, J. H.; Robertson, D. C.

    1989-02-01

    This report describes how to implement and use the Strategic High-Altitude Radiance Code (SHARC). SHARC calculates atmospheric radiation for paths from 60 to 300 km altitude in the 2 to 40 micron spectral region. It models radiation due to NLTE (Non-Local Thermodynamic Equilibrium) molecular emissions which are the dominant sources at these altitudes. This initial version of SHARC includes the five strongest IR radiators, CO2, NO, O3, H2O, and CO. The code is available on magnetic tape and can be obtained by written request to AFGL/OPB.

  9. ANALISIS TIPOGRAFI PADA LOGOTYPE BAND FORGOTTEN

    Directory of Open Access Journals (Sweden)

    Atang Riyan Isnandar

    2016-12-01

    Full Text Available Abstrak Forgotten merupakan band asal kota Bandung yang beraliran death metal. Band ini telah memiliki beberapa album yang cukup sukses. Salah satu faktor yang turut berperan penting dalam album-album Forgotten adalah desain sampul album. Sampul album merupakan identitas dan pesan dari musik yang dibawakan oleh Forgotten. Dalam sampul album, terdapat salah satu elemen visual yaitu Tipografi. Salah satu peran tipografi dalam sampul album Forgotten adalah sebagai logotype dari band. Yang menarik, dari lima album yang telah dirilis Forgotten yaitu “Future Syndrome” (1997, “Obsesi Mati” (2000, “Tuhan Telah Mati” (2001, “Tiga Angka Enam” (2003 dan “Laras Perlaya” (2011 adalah tampilan logotype band yang selalu berbeda. Perubahan logotype Forgotten disebabkan oleh beberapa faktor seperti adanya perubahan selera, transformasi musik dan pergantian personil yang dialami oleh band Forgotten. Perubahan ini berakibat pada munculnya kesan visual yang berbeda-beda dari masing-masing logotype di setiap sampul albumnya. Apalagi logotype band dengan genre death metal memiliki kecendrungan yang unik, dekoratif, bahkan sulit untuk dibaca. Oleh karena itu untuk mengetahui kesan visual yang dimunculkan oleh setiap logotype akan dilakukan penelitian dengan pendekatan tipografi. Tujuan dari penelitian ini adalah selain untuk mengetahui perubahan logotype dari kelima sampul album yang telah dirilis oleh Forgotten juga ingin mengetahui kesan visual terhadap tipografi terkait dengan prinsip kejelasan (legibility, keterbacaan (readability dan kemampuannya untuk dilihat pada jarak tertentu (visibility. Kata Kunci: Sampul Album, Tipografi, Logotype, Forgotten Abstract Forgotten is a band from Bandung, the death metal genre. The band has had some fairly successful album. One of important factor in albums Forgotten is the album cover design. The album cover are the identity and the message of the music performed by the Forgotten. In the cover of the album

  10. Estimating carbon dioxide fluxes from temperate mountain grasslands using broad-band vegetation indices

    Directory of Open Access Journals (Sweden)

    G. Wohlfahrt

    2010-02-01

    Full Text Available The broad-band normalised difference vegetation index (NDVI and the simple ratio (SR were calculated from measurements of reflectance of photosynthetically active and short-wave radiation at two temperate mountain grasslands in Austria and related to the net ecosystem CO2 exchange (NEE measured concurrently by means of the eddy covariance method. There was no significant statistical difference between the relationships of midday mean NEE with narrow- and broad-band NDVI and SR, measured during and calculated for that same time window, respectively. The skill of broad-band NDVI and SR in predicting CO2 fluxes was higher for metrics dominated by gross photosynthesis and lowest for ecosystem respiration, with NEE in between. A method based on a simple light response model whose parameters were parameterised based on broad-band NDVI allowed to improve predictions of daily NEE and is suggested to hold promise for filling gaps in the NEE time series. Relationships of CO2 flux metrics with broad-band NDVI and SR however generally differed between the two studied grassland sites indicting an influence of additional factors not yet accounted for.

  11. Processing and fusion for human body terahertz dual-band passive image

    Science.gov (United States)

    Tian, Li; Shen, Yanchun; Jin, Weiqi; Zhao, Guozhong; Cai, Yi

    2016-11-01

    Compared with microwave, THz has higher resolution, and compared with infrared, THz has better penetrability. Human body radiate THz also, its photon energy is low, it is harmless to human body. So THz has great potential applications in the body searching system. Dual-band images may contain different information for the same scene, so THz dual-band imaging have been a significant research subject of THz technology. Base on the dual-band THz passive imaging system which is composed of a 94GHz and a 250GHz cell detector, this paper researched the preprocessing and fusion algorithm for THz dual-band images. Firstly, THz images have such problems: large noise, low SNR, low contrast, low details. Secondly, the stability problem of the optical mechanical scanning system makes the images less repetitive, obvious stripes and low definition. Aiming at these situations, this paper used the BM3D de-noising algorithm to filter noise and correct the scanning problem. Furthermore, translation, rotation and scaling exist between the two images, after registered by the intensity-base registration algorithm, and enhanced by the adaptive histogram equalization algorithm, the images are fused by image fusion algorithm based on wavelet. This effectively reduced the image noise, scan distortion and matching error, improved the details, enhanced the contrast. It is helpful to improve the detection efficiency of hidden objects too. Method in this paper has a substantial effect for improving the dual-band THz passive imaging system's performance and promoting technology practical.

  12. A comparative in vivo and in vitro L-band EPR study of irradiated rat incisors

    International Nuclear Information System (INIS)

    Zdravkova, M.; Gallez, B.; Debuyst, R.

    2005-01-01

    L-band (∼1GHz) EPR has the potential to measure the absorbed radiation dose in human teeth inside the mouth (in vivo analyses). One crucial point in the development of the method is to know if dosimetry evaluation carried out in vivo after accidental exposures can be reliably based on calibration curves built in vitro. The aim of the present work is to specifically address this point. First, we compared L-band in vitro and in vivo analyses in irradiated rat teeth and estimated the possible loss in in vivo experiments due to rat movements and mouth proximity. Second, the lower pair of rat incisors were analysed by L-band EPR before and after irradiation (50Gy), first on the living rat, then on the same dead rat, finally after extraction of the teeth. X-band powder spectra were also taken after crushing of the two teeth. Irradiations of dead rats and extracted teeth were also carried out. Comparing L-band spectra obtained with living rats and removed heads does not show any significant difference due to possible small rat movements or breathing. Relative standard deviations of the amplitudes of the dosimetric signal are quite high (27-54%). Nevertheless, it seems to be a tendency to have higher signals in irradiated extracted teeth than in irradiated animals

  13. Reduction of the In-Band RCS of Microstrip Patch Antenna by Using Offset Feeding Technique

    Directory of Open Access Journals (Sweden)

    Weiwei Xu

    2014-01-01

    Full Text Available This paper presents a method for implementing a low in-band scattering design for microstrip patch antennas based on the analysis of structural mode scattering and radiation characteristics. The antenna structure is first designed to have the lowest structural mode scattering in a desired frequency band. The operating frequency band of the antenna is then changed to coincide with that of the lowest structural mode scattering by adjusting the feed position on the antenna (offset feeding to achieve an antenna with low in-band radar cross section (RCS. In order to reduce the level of cross polarization of the antenna caused by offset feeding, symmetry feeding structures for both single patch antennas and two-patch arrays are proposed. Examples that show the efficiency of the method are given, and the results illustrate that the in-band RCS of the proposed antennas can be reduced by as much as 17 dBsm for plane waves impinging from the normal direction compared to patch antennas fed by conventional methods.

  14. Radiation enteropathy

    Energy Technology Data Exchange (ETDEWEB)

    Farthmann, E.H. (Chirurgische Universitaetsklinik, Freiburg im Breisgau (Germany)); Imdahl, A. (Chirurgische Universitaetsklinik, Freiburg im Breisgau (Germany)); Eggstein, S. (Chirurgische Universitaetsklinik, Freiburg im Breisgau (Germany))

    1994-08-01

    The pathogenesis, clinical picture, diagnosis and treatment of radiation damage to the gut are described. The progress of 90 patients operated on in the Chirurgische Universitaetsklinik Freiburg is retrospectively evaluated. Haemorrhage, vomiting, diarrhoea and, occasionally, perforation are the signs of acute radiation enteropathy, which appears weeks or months after radiotherapy. Expect for perforations, these can usually be treated conservatively. Chronic radiation enteropathy does not manifest itself until years after irradiation, with diarrhoea, obstruction and the development of fistulae. The acute ileus can often be relieved with decompression tubes. After localising the stenosis radiologically with a contrast medium, and improvement in the general condition, many cases require operative intervention. This usually consists of resection, the establishment of a bypass anastomosis or enterostomy. In 44% of the patients postoperative complications followed, with a mortality of 22%. The cause of the high complication rate is partly the poor general condition of the patient, and partly the radiation induced impairment in wound healing, which may lead to insufficiency of the anastomosis and the development of fistulae. (orig./MG)

  15. Radiation detectors

    International Nuclear Information System (INIS)

    2013-01-01

    This sixth chapter presents the operational principles of the radiation detectors; detection using photographic emulsions; thermoluminescent detectors; gas detectors; scintillation detectors; liquid scintillation detectors; detectors using semiconductor materials; calibration of detectors; Bragg-Gray theory; measurement chain and uncertainties associated to measurements

  16. Radiation processing

    International Nuclear Information System (INIS)

    Noriah Mod Ali

    2005-01-01

    This chapter covers the basic principle and application of radiation technology. The topic titled specific application discussed briefly the following subtopics: 1) Polymer modification - crosslinking, polymerisation, degradation, grafting; 2) Medical sterilisation; 3) Food irradiation; 4) Environmental protection - waste processing, pollutants treatment

  17. Radiation dosimetry

    International Nuclear Information System (INIS)

    Aymar A, J.; Medina G, H.

    1988-01-01

    Film is one of the most simple ways to detect radiation although for film as dosimeters a careful attention is required in many aspects, such as emulsion characteristics, film response capacity processing techniques and interpretation of the exposition. Surpassing these factors the film dosimeter is the most reliable

  18. Radiation enteropathy

    International Nuclear Information System (INIS)

    Farthmann, E.H.; Imdahl, A.; Eggstein, S.

    1994-01-01

    The pathogenesis, clinical picture, diagnosis and treatment of radiation damage to the gut are described. The progress of 90 patients operated on in the Chirurgische Universitaetsklinik Freiburg is retrospectively evaluated. Haemorrhage, vomiting, diarrhoea and, occasionally, perforation are the signs of acute radiation enteropathy, which appears weeks or months after radiotherapy. Expect for perforations, these can usually be treated conservatively. Chronic radiation enteropathy does not manifest itself until years after irradiation, with diarrhoea, obstruction and the development of fistulae. The acute ileus can often be relieved with decompression tubes. After localising the stenosis radiologically with a contrast medium, and improvement in the general condition, many cases require operative intervention. This usually consists of resection, the establishment of a bypass anastomosis or enterostomy. In 44% of the patients postoperative complications followed, with a mortality of 22%. The cause of the high complication rate is partly the poor general condition of the patient, and partly the radiation induced impairment in wound healing, which may lead to insufficiency of the anastomosis and the development of fistulae. (orig./MG) [de

  19. Radiation dosage

    International Nuclear Information System (INIS)

    Finston, Roland

    1986-01-01

    Radiation dosage at Bikini Atoll is the result of current soil contamination, a relic of the nuclear weapons testing program of some 30 years ago. The principal contaminants today and some of their physical properties are listed: cesium-137, strontium-90, plutonium -239, 240 and americium-241. Cobalt-60 contributes less than 1 to the dose and is not considered significant. A resident of the atoll would accumulate radiation dose (rem) in two ways -- by exposure to radiation emanating from the ground and vegetation, and by exposure to radiation released in the spontaneous decay of radionuclides that have entered his body during the ingestion of locally grown foods. The latter process would account for some 90% of the dose; cesium-137 would be responsible for 0 90% of it. Since BARC's method of estimating dosage differs in some respects from that employed by the Lawrence Livermore National Laboratory (LLNL), (Ref.1, LLNL 1982) we are presenting our method in detail. The differences have two sources. First, the numbers used by BARC for the daily ingestion of radionuclides via the diet are higher than LLNL's. Second, BARC's calculation of dose from radionuclide intake utilizes the ICRP system. The net result is that BARC doses are consistently higher than LLNL doses, and in this respect are more conservative

  20. Radiation accidents

    International Nuclear Information System (INIS)

    Saenger, E.L.

    1986-01-01

    It is essential that emergency physicians understand ways to manage patients contaminated by radioactive materials and/or exposed to external radiation sources. Contamination accidents require careful surveys to identify the metabolic pathway of the radionuclides to guide prognosis and treatment. The level of treatment required will depend on careful surveys and meticulous decontamination. There is no specific therapy for the acute radiation syndrome. Prophylactic antibodies are desirable. For severely exposed patients treatment is similar to the supportive care given to patients undergoing organ transplantation. For high-dose extremity injury, no methods have been developed to reverse the fibrosing endarteritis that eventually leads to tissue death so frequently found with this type of injury. Although the Three Mile Island episode of March 1979 created tremendous public concern, there were no radiation injuries. The contamination outside the reactor building and the release of radioiodine were negligible. The accidental fuel element meltdown at Chernobyl, USSR, resulted in many cases of acute radiation syndrome. More than 100,000 people were exposed to high levels of radioactive fallout. The general principles outlined here are applicable to accidents of that degree of severity

  1. 47 CFR 15.714 - TV bands database administration fees.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false TV bands database administration fees. 15.714 Section 15.714 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Television Band Devices § 15.714 TV bands database administration fees. (a) A TV bands database administrator...

  2. 47 CFR 15.715 - TV bands database administrator.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false TV bands database administrator. 15.715 Section... Band Devices § 15.715 TV bands database administrator. The Commission will designate one or more entities to administer a TV bands database. Each database administrator shall: (a) Maintain a database that...

  3. New Kronig-Penney Equation Emphasizing the Band Edge Conditions

    Science.gov (United States)

    Szmulowicz, Frank

    2008-01-01

    The Kronig-Penney problem is a textbook example for discussing band dispersions and band gap formation in periodic layered media. For example, in photonic crystals, the behaviour of bands next to the band edges is important for further discussions of such effects as inhibited light emission, slow light and negative index of refraction. However,…

  4. Predicting superdeformed rotational band-head spin in A∼ 190 ...

    Indian Academy of Sciences (India)

    The band-head spin (0) of superdeformed (SD) rotational bands in ∼ 190 mass region is predicted using the variable moment of inertia (VMI) model for 66 SD rotational bands. The superdeformed rotational bands exhibited considerably good rotational property and rigid behaviour. The transition energies were ...

  5. Introduction to radiation biology

    International Nuclear Information System (INIS)

    Gensicke, F.

    1977-01-01

    The textbook is written with special regard to radiation protection of man. It shall enable the reader to assess the potential radiation risks to living organisms and lead him to an insight into radiation protection measures. The following topics are covered: physical fundamentals of ionizing radiations; physical and chemical fundamentals of biological radiation effects; radiation effects on cells, organs, organ systems, and whole animal organisms focussing on mammals and man; modification of radiation effects; chemical radiation protection; therapy of radiation injuries; radionuclide kinetics; biological radiation effects in connection with radiation hazards and with the limitation of radiation exposure. It is intended for vocational education of medical personnel

  6. Stomatal closure by ultraviolet radiation

    International Nuclear Information System (INIS)

    Negash, L.; Björn, L.O.

    1986-01-01

    The effect of ultraviolet radiation (UV) (255–325 nm) on stomatal closure was investigated on tef [Eragrostis tef (Zucc) Trotter] in the presence of white light (ca 50 ·mol m −2 s −1 ). The action spectrum showed that UV (ca 2 ·mol m −2 s −1 , half band width about 10 nm) of 285 nm or shorter wavelengths was very efficient in causing stomatal closure. The effectiveness decreased sharply towards longer wavelengths. Radiation of 313 nm or longer wavelengths was practically without effect. Increasing UV intensity increased stomatal resistance. When stronger white light (5 to 9 times stronger than the one used during irradiation) was administered, stomates re-opened rapidly irrespective of whether the UV was on or off, although a subsequent gradual closing tendency was observed when the UV was on. (author)

  7. Statistical study of auroral omega bands

    Directory of Open Access Journals (Sweden)

    N. Partamies

    2017-09-01

    Full Text Available The presence of very few statistical studies on auroral omega bands motivated us to test-use a semi-automatic method for identifying large-scale undulations of the diffuse aurora boundary and to investigate their occurrence. Five identical all-sky cameras with overlapping fields of view provided data for 438 auroral omega-like structures over Fennoscandian Lapland from 1996 to 2007. The results from this set of omega band events agree remarkably well with previous observations of omega band occurrence in magnetic local time (MLT, lifetime, location between the region 1 and 2 field-aligned currents, as well as current density estimates. The average peak emission height of omega forms corresponds to the estimated precipitation energies of a few keV, which experienced no significant change during the events. Analysis of both local and global magnetic indices demonstrates that omega bands are observed during substorm expansion and recovery phases that are more intense than average substorm expansion and recovery phases in the same region. The omega occurrence with respect to the substorm expansion and recovery phases is in a very good agreement with an earlier observed distribution of fast earthward flows in the plasma sheet during expansion and recovery phases. These findings support the theory that omegas are produced by fast earthward flows and auroral streamers, despite the rarity of good conjugate observations.

  8. S-Band Doppler Wave Radar System

    Directory of Open Access Journals (Sweden)

    Zezong Chen

    2017-12-01

    Full Text Available In this paper, a novel shore-based S-band microwave Doppler coherent wave radar (Microwave Ocean Remote SEnsor (MORSE is designed to improve wave measurements. Marine radars, which operate in the X band, have been widely used for ocean monitoring because of their low cost, small size and flexibility. However, because of the non-coherent measurements and strong absorption of X-band radio waves by rain, these radar systems suffer considerable performance loss in moist weather. Furthermore, frequent calibrations to modify the modulation transfer function are required. To overcome these shortcomings, MORSE, which operates in the S band, was developed by Wuhan University. Because of the coherent measurements of this sensor, it is able to measure the radial velocity of water particles via the Doppler effect. Then the relation between the velocity spectrum and wave height spectrum can be used to obtain the wave height spectra. Finally, wave parameters are estimated from the wave height spectra by the spectrum moment method. Comparisons between MORSE and Waverider MKIII are conducted in this study, and the results, including the non-directional wave height spectra, significant wave height and average wave period, are calculated and displayed. The correlation coefficient of the significant wave height is larger than 0.9, whereas that of the average wave period is approximately 0.4, demonstrating the effectiveness of MORSE for the continuous monitoring of ocean areas with high accuracy.

  9. Deformed configurations, band structures and spectroscopic ...

    Indian Academy of Sciences (India)

    2014-03-20

    Mar 20, 2014 ... The deformed configurations and rotational band structures in =50 Ge and Se nuclei are studied by deformed Hartree–Fock with quadrupole constraint and angular momentum projection. Apart from the `almost' spherical HF solution, a well-deformed configuration occurs at low excitation. A deformed ...

  10. Deformed configurations, band structures and spectroscopic ...

    Indian Academy of Sciences (India)

    2014-03-20

    Mar 20, 2014 ... Here, we study theoretically the low-lying as well as the excited deformed bands and their electromagnetic properties to search for various structures, spherical and deformed, of the exotic nuclei 82Ge and 84Se by employing the deformed Hartree–Fock (HF) and angular momentum (J) projection method ...

  11. Energy bands and gaps near an impurity

    Czech Academy of Sciences Publication Activity Database

    Mihóková, Eva; Schulman, L. S.

    2016-01-01

    Roč. 380, č. 41 (2016), s. 3430-3433 ISSN 0375-9601 R&D Projects: GA ČR GA13-09876S Institutional support: RVO:68378271 Keywords : crystal structure * impurity * modeling * energy bands Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.772, year: 2016

  12. Teaching Strategies for High School Band.

    Science.gov (United States)

    Teaching Music, 1999

    1999-01-01

    Provides a strategy, from the book entitled "Strategies for Teaching High School Band," that addresses Standard 8B of the National Standards for Music Education. Explains that students will discover relationships among music, visual art, and architecture of the Classical period. (CMK)

  13. Radio Band Observations of Blazar Variability

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... The properties of blazar variability in the radio band are studied using the unique combination of temporal resolution from single dish monitoring and spatial resolution from VLBA imaging. Such measurements now available in all four Stokes parameters, together with theoretical simulations, identify the ...

  14. Electron band theory 1952-1962

    International Nuclear Information System (INIS)

    Lomer, W.M.

    1980-01-01

    Work undertaken by the Theoretical Physics Division between 1952 and 1965 to obtain an understanding of electrons in metals, with uranium and the actinides and the structurally-important transition metals as the main targets is examined. A main result of that period was a conviction that the majority of the physical properties of all metals, except the 4f rare-earth series and the actinides beyond uranium, were dominated by band effects which could be described well enough for most purposes by simple one-electron calculations with simple self-consistent fields. The period from 1960 on showed increasingly clearly the necessity of incorporating relativistic spin-orbit coupling terms in the heavy metals, and some 'local exchange field' correction to the fields close to nuclei. The problems of the non-local interaction of spins - highly important for alloy theory and for antiferromagnetic instability -required the evolution of computers large enough to produce wave-functions at all wave-vectors for all bands so that the susceptibility at arbitrary wave-vector could be computed. This work has not proved to be very illuminating so far, and much interest again focusses today on heuristic arguments that give qualitative descriptions of band structures, such as canonical d-bands to account for crystal structure. (UK)

  15. The end of the unique myocardial band

    DEFF Research Database (Denmark)

    MacIver, David H; Partridge, John B; Agger, Peter

    2018-01-01

    Two of the leading concepts of mural ventricular architecture are the unique myocardial band and the myocardial mesh model. We have described, in an accompanying article published in this journal, how the anatomical, histological and high-resolution computed tomographic studies strongly favour...

  16. Faraday Rotation and L Band Oceanographic Measurements

    DEFF Research Database (Denmark)

    Skou, Niels

    2003-01-01

    Spaceborne radiometric measurements of the L band brightness temperature over the oceans make it possible to estimate sea surface salinity. However, Faraday rotation in the ionosphere disturbs the signals and must be corrected. Two different ways of assessing the disturbance directly from...

  17. Fluorescence bands and chlorophyll a forms

    NARCIS (Netherlands)

    Goedheer, J.C.

    1964-01-01

    Fluorescence spectra were determined at temperatures between 20° and −196° for a number of photosynthetic organisms. Below −90° the single fluorescence maximum around 685 mμ was replaced by a system of three bands, at 686, 696 and 717–720 mμ in algal cells. Cooling usually resulted in a decrease of

  18. Phononic band gap structures as optimal designs

    DEFF Research Database (Denmark)

    Jensen, Jakob Søndergaard; Sigmund, Ole

    2003-01-01

    In this paper we use topology optimization to design phononic band gap structures. We consider 2D structures subjected to periodic loading and obtain the distribution of two materials with high contrast in material properties that gives the minimal vibrational response of the structure. Both in...

  19. Conduction bands in classical periodic potentials

    Indian Academy of Sciences (India)

    The particle may hop from classically allowed site to nearest-neighbour classically allowed site in the potential, behaving as if it were a quantum particle in an energy gap and undergoing repeated tunnelling processes or; the particle may behave as a quantum particle in a conduction band and drift at a constant average ...

  20. PHARUS: A C-band Airborne SAR

    NARCIS (Netherlands)

    Hoogeboom, P.; Koomen, P.J.; Pouwels, H.; Snoeij, P.

    1990-01-01

    In The Netherlands a plan to design aircraft and build a polarimetric C-band SAR system of a novel design, called PHARUS (PHased Array Universal SAR) is carried out by three institutes. These institutes are the Physics and Electronics Laboratory TNO in The Hague (prime contractor and project

  1. Superdeformed rotational bands in Pu-240

    NARCIS (Netherlands)

    Hunyadi, M; Gassmann, D; Krasznahorkay, A; Habs, D; Csatlos, M; Eisermann, Y; Faestermann, T; Graw, G; Gulyas, J; Hertenberger, R; Maier, HJ; Mate, Z; Metz, A; Thirolf, P; Chromik, M; van der Werf, SY

    The intermediate structure of the fission resonances has been observed in Pu-240. A resonance structure found around the excitation energy of 4.5 MeV was interpreted as a group of K-pi = 0(+) superdeformed rotational bands. The moments of inertia and level density distributions were also deduced for

  2. Band-Structure of Thallium by the LMTO Method

    DEFF Research Database (Denmark)

    Holtham, P. M.; Jan, J. P.; Skriver, Hans Lomholt

    1977-01-01

    The relativistic band structure of thallium has been calculated using the linear muffin-tin orbital (LMTO) method. The positions and extents of the bands were found to follow the Wigner-Seitz rule approximately, and the origin of the dispersion of the bands was established from the canonical s...... and p bands for the HCP structure. Energy bands have been evaluated both with and without spin-orbit coupling which is particularly large in thallium. Energy bands close to the Fermi level were found to be mainly 6p like in character. The 6s states lay below the 6p bands and were separated from them...

  3. Dual-Band Operation of a Circularly Polarized Four-Arm Curl Antenna with Asymmetric Arm Length

    Directory of Open Access Journals (Sweden)

    Son Xuat Ta

    2016-01-01

    Full Text Available This paper presents dual-band operation of a single-feed composite cavity-backed four-arm curl antenna. Dual-band operation is achieved with the presence of the asymmetrical arm structure. A pair of vacant-quarter printed rings is used in the feed structure to produce a good circular polarization (CP at both bands. The cavity-backed reflector is employed to improve the CP radiation characteristics in terms of the 3-dB axial ratio beamwidth and broadside gain. The proposed antenna is widely applicable in dual-band communication systems that have a small frequency ratio. Examples of such a system are global positioning systems.

  4. Band profiles of Mott-insulator/band-insulator heterointerfaces revealed by photocurrent and electromodulation spectroscopies

    Science.gov (United States)

    Nakamura, Masao

    2011-03-01

    Heterointerfaces of Mott insulators provide a good laboratory to explore unprecedented electronic states induced by the strong electron correlation. Although a number of intriguing phenomena have been reported so far, their fundamental origins have not been fully addressed yet. This is partly because the interface band profile, which is one of the most basic knowledge to understand the interface electronic states, is still left to be unveiled. In this study, we have investigated in detail the interface band profiles of Mott insulators employing photocurrent and electromodulation spectroscopies as well as the conventional current-voltage and capacitance-voltage characterizations. We chose p -type (LaMn O3 and La 2 Cu O4) and n -type (SrMn O3 and Sm 2 Cu O4) as the Mott insulators and these are epitaxially connected to Nb doped SrTi O3 (electron-doped band insulator). The photocurrent action spectra for these heterojunctions showed negligibly-small band reconstruction as well as the existence of band bending and discontinuity in the Mott insulators, which are of no salient discrepancy with the rigid-band picture valid in the interface of conventional semiconductors~. However, the electromodulation spectra clearly indicate the band reconstruction in the Mott insulators~. The results mean that the rigid-band picture is valid in the low carrier-density regime even in Mott-insulator/band-insulator interfaces, but the intentional charge modulation leads the electron correlation effect in the Mott insulators. This work was done in collaboration with A. Sawa, J. Fujioka, M. Kawasaki and Y. Tokura. I acknowledge the support from Japan Society for the Promotion of Science (JSPS) through its ``Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST Program)''.

  5. Detailed observations of the source of terrestrial narrowband electromagnetic radiation

    Science.gov (United States)

    Kurth, W. S.

    1982-01-01

    Detailed observations are presented of a region near the terrestrial plasmapause where narrowband electromagnetic radiation (previously called escaping nonthermal continuum radiation) is being generated. These observations show a direct correspondence between the narrowband radio emissions and electron cyclotron harmonic waves near the upper hybrid resonance frequency. In addition, electromagnetic radiation propagating in the Z-mode is observed in the source region which provides an extremely accurate determination of the electron plasma frequency and, hence, density profile of the source region. The data strongly suggest that electrostatic waves and not Cerenkov radiation are the source of the banded radio emissions and define the coupling which must be described by any viable theory.

  6. UWB Filtering Power Divider with Two Narrow Notch-bands and Wide Stop-band

    Science.gov (United States)

    Wei, Feng; Wang, Xin-Yi; Zou, Xin Tong; Shi, Xiao Wei

    2017-12-01

    A compact filtering ultra-wideband (UWB) microstrip power divider (PD) with two sharply rejected notch-bands and wide stopband is analyzed and designed in this paper. The proposed UWB PD is based on a conventional Wilkinson power divider, while two stub loaded resonators (SLRs) are coupled into two symmetrical output ports to achieve a bandpass filtering response. The simplified composite right/left-handed (SCRLH) resonators are employed to generate the dual notched bands. Defected ground structure (DGS) is introduced to improve the passband performance. Good insertion/return losses, isolation and notch-band rejection are achieved as demonstrated in both simulation and experiment.

  7. Diffuse solar radiation and associated meteorological parameters in India

    Directory of Open Access Journals (Sweden)

    A. B. Bhattacharya

    1996-10-01

    Full Text Available Solar diffuse radiation data including global radiation, shortwave and longwave balances, net radiation and sunshine hours have been extensively analyzed to study the variation of diffuse radiation with turbidity and cloud discharges appearing in the form of atmospherics over the tropics. Results of surface radiation measurements at Calcutta, Poona, Delhi and Madras are presented together with some meteorological parameters. The monthly values of diffuse radiation and the monthly ratios of diffuse to global solar radiation have been examined, with a special emphasis in relation to the noise level of atmospherics at Calcutta in the very low frequency band. The results exhibit some definite seasonal changes which appear to be in close agreement with one another.

  8. Diffuse solar radiation and associated meteorological parameters in India

    Directory of Open Access Journals (Sweden)

    A. B. Bhattacharya

    Full Text Available Solar diffuse radiation data including global radiation, shortwave and longwave balances, net radiation and sunshine hours have been extensively analyzed to study the variation of diffuse radiation with turbidity and cloud discharges appearing in the form of atmospherics over the tropics. Results of surface radiation measurements at Calcutta, Poona, Delhi and Madras are presented together with some meteorological parameters. The monthly values of diffuse radiation and the monthly ratios of diffuse to global solar radiation have been examined, with a special emphasis in relation to the noise level of atmospherics at Calcutta in the very low frequency band. The results exhibit some definite seasonal changes which appear to be in close agreement with one another.

  9. Smoothed Particle Hydrodynamics Coupled with Radiation Transfer

    Science.gov (United States)

    Susa, Hajime

    2006-04-01

    We have constructed a brand-new radiation hydrodynamics solver based upon Smoothed Particle Hydrodynamics, which works on a parallel computer system. The code is designed to investigate the formation and evolution of first-generation objects at z ≳ 10, where the radiative feedback from various sources plays important roles. The code can compute the fraction of chemical species e, H+, H, H-, H2, and H+2 by by fully implicit time integration. It also can deal with multiple sources of ionizing radiation, as well as radiation at Lyman-Werner band. We compare the results for a few test calculations with the results of one-dimensional simulations, in which we find good agreements with each other. We also evaluate the speedup by parallelization, which is found to be almost ideal, as long as the number of sources is comparable to the number of processors.

  10. Radiation Dosimetry Study in Dental Enamel of Human Tooth Using Electron Paramagnetic Resonance

    Science.gov (United States)

    De, Tania; Romanyukha, Alex; Pass, Barry; Misra, Prabhakar

    2009-07-01

    Electron paramagnetic resonance (EPR) dosimetry of tooth enamel is used for individual dose reconstruction following radiation accidents. The purpose of this study is to develop a rapid, minimally invasive technique of obtaining a sample of dental enamel small enough to not disturb the structure and functionality of a tooth and to improve the sensitivity of the spectral signals using X-band (9.4 GHz) and Q-band (34 GHz) EPR technique. In this study EPR measurements in X-band were performed on 100 mg isotropic powdered enamel samples and Q-band was performed on 4 mg, 1×1×3 mm enamel biopsy samples. All samples were obtained from discarded teeth collected during normal dental treatment. To study the variation of the Radiation-Induced Signal (RIS) at different orientations in the applied magnetic field, samples were placed in the resonance cavity for Q-band EPR. X-band EPR measurements were performed on 100 mg isotropic powdered enamel samples. In X-band spectra, the RIS is distinct from the "native" radiation-independent signal only for doses >0.5 Gy. Q-band, however, resolves the RIS and "native" signals and improves sensitivity by a factor of 20, enabling measurements in 2-4 mg tooth enamel samples, as compared to 100 mg for X-band. The estimated lower limit of Q-band dose measurement is 0.5 Gy. Q-band EPR enamel dosimetry results in greater sensitivity and smaller sample size through enhanced spectral resolution. Thus, this can be a valuable technique for population triage in the event of detonation of a radiation dispersal device ("dirty" bomb) or other radiation event with massive casualties. Further, the small 4 mg samples can be obtained by a minimally-invasive biopsy technique.

  11. The marginal band system in nymphalid butterfly wings.

    Science.gov (United States)

    Taira, Wataru; Kinjo, Seira; Otaki, Joji M

    2015-01-01

    Butterfly wing color patterns are highly complex and diverse, but they are believed to be derived from the nymphalid groundplan, which is composed of several color pattern systems. Among these pattern systems, the marginal band system, including marginal and submarginal bands, has rarely been studied. Here, we examined the color pattern diversity of the marginal band system among nymphalid butterflies. Marginal and submarginal bands are usually expressed as a pair of linear bands aligned with the wing margin. However, a submarginal band can be expressed as a broken band, an elongated oval, or a single dot. The marginal focus, usually a white dot at the middle of a wing compartment along the wing edge, corresponds to the pupal edge spot, one of the pupal cuticle spots that signify the locations of color pattern organizing centers. A marginal band can be expressed as a semicircle, an elongated oval, or a pair of eyespot-like structures, which suggest the organizing activity of the marginal focus. Physical damage at the pupal edge spot leads to distal dislocation of the submarginal band in Junonia almana and in Vanessa indica, suggesting that the marginal focus functions as an organizing center for the marginal band system. Taken together, we conclude that the marginal band system is developmentally equivalent to other symmetry systems. Additionally, the marginal band is likely a core element and the submarginal band a paracore element of the marginal band system, and both bands are primarily specified by the marginal focus organizing center.

  12. Risk Factors: Radiation

    Science.gov (United States)

    Radiation of certain wavelengths, called ionizing radiation, has enough energy to damage DNA and cause cancer. Ionizing radiation includes radon, x-rays, gamma rays, and other forms of high-energy radiation.

  13. Radiation Therapy for Cancer

    Science.gov (United States)

    ... material placed in the body near cancer cells ( internal radiation therapy , also called brachytherapy ). Systemic radiation therapy uses radioactive ... material placed in the body near cancer cells (internal radiation therapy, more commonly called brachytherapy). Systemic radiation therapy uses ...

  14. Chest radiation - discharge

    Science.gov (United States)

    Radiation - chest - discharge; Cancer - chest radiation; Lymphoma - chest radiation ... When you have radiation treatment for cancer, your body goes through changes. About 2 weeks after your first treatment: It may be hard ...

  15. Interplay between six wave mixing photonic band gap signal and second-order nonlinear signal in electromagnetically induced grating.

    Science.gov (United States)

    Wang, Zhiguo; Gao, Mengqin; Ullah, Zakir; Zhang, Dan; Chen, Haixia; Gao, Hong; Zhang, Yanpeng

    2015-09-21

    For the first time, we experimentally and theoretically research about the second-order nonlinear signal (SNS) including electromagnetically induced absorbing (EIA) and electromagnetically induced gain (EIG), six wave mixing band gap signal (SWM BGS) resulting from photonic band gap structure in an inverted Y-type four level system with the electromagnetically induced grating. The interplay between the SNS and SWM BGS is illustrated clearly for the first time. When we change the frequency detuning to make the SWM BGS and SNS overlap, the SWM BGS is suppressed and the intensity of SNS is strongest near the resonance point. We can control the intensity of the SWM BGS and EIG caused by the classic effect through changing the power of coupling field. And the changes on the EIA generated by the quantum effect are obtained by changing the power of dressing field. Since the SWM BGS is the enhancement of the four wave mixing band gap signal (FWM BGS), when we set FWM BGS as the input and SNS as the modulation role to control the amplification amplitude for the FWM BGS in our scheme, the adjustable optical amplifier can be obtained.

  16. Radiation effects

    International Nuclear Information System (INIS)

    Collings, E.W.

    1986-01-01

    An important cause of deterioration in superconducting magnets intended for high-energy physics and fusion-reactor applications is radiation damage. The present chapter deals chiefly with the effects of electron, proton, gamma and neutron irradiation on the properties of stabilized Ti-Nb-base composite superconductors. The authors examine the particle-accelerator environment, electron irradiation of Ti-Nb superconductor, proton irradiation of Ti-Nb superconductor and its stabilizer, and deuteron irradiation of Ti-Nb superconductor. A section discussing the fusion reactor environment in general is presented, and the two principal classes of fusion reactor based on the magnetic-confinement concept, namely the tokamak and the mirrormachine are examined. Also discussed is neutron irradiation of Cu/TiNb composite superconductors and critical current density of neutronirradiated Ti-Nb. Finally, radiation damage to stabilizer and insulating materials is described

  17. Radiation detector

    International Nuclear Information System (INIS)

    Gillies, W.

    1980-01-01

    The radiation detector for measuring e.g. a neutron flux consists of a central emitter, an insulating shell arranged around it, and a tube-shaped collector enclosing both. The emitter itself is composed of a great number of stranded, spiral wires of small diameter giving a defined flexibility to the detector. For emitter material Pt, Rh, V, Co, Ce, Os or Ta may be used. (DG) [de

  18. Radiation accidents

    International Nuclear Information System (INIS)

    Poplavskij, K.K.; Smorodintseva, G.I.

    1978-01-01

    On the basis of a critical analysis of the available data on causes and consequences of radiation accidents (RA), a classification of RA by severity (five groups of accidents) according to biomedical consequences and categories of exposed personnel is proposed. A RA is defined and its main characteristics are described. Methods of RA prevention are proposed, as is a plan of specific measures to deal with RA in accordance with the proposed classification

  19. Radiation retinopathy

    International Nuclear Information System (INIS)

    Wara, W.M.; Irvine, A.R.; Neger, R.E.; Howes, E.L. Jr.; Phillips, T.L.

    1979-01-01

    The records were reviewed of all patients treated with irradiation to the eye at the University of California, San Francisco, between 1960 and 1975. Eight patients were identified who had developed radiation retinopathy 1 to 3 years postrirradiation. Lesions included retinal vascular occlusions, hemorrhages, microaneurysms, exudates, neovascularization, vitreous hemorrhage, retinal detachments, and optic atrophy with blindness. Four patients had received less than 5000 rad in 6 weeks to the retina, a dose usually considered within normal tissue tolerance

  20. Radiation shelter

    International Nuclear Information System (INIS)

    Crookes, T.A.

    1982-01-01

    This patent application describes a shelter comprising a cavity for receiving life to be sheltered; a roof for covering at least a portion of said cavity, and at least one aqueous, protective barrier layer adapted to prevent transmission through said roof and into said cavity of at least a portion of radiation in a predetermined spectrum. The cavity walls may be impregnated with an oil suitable for dressing burns. (author)

  1. Space Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, William R.

    1968-01-01

    This booklet discusses three kinds of space radiation, cosmic rays, Van Allen Belts, and solar plasma. Cosmic rays are penetrating particles that we cannot see, hear or feel, which come from distant stars. Van Allen Belts, named after their discoverer are great belts of protons and electrons that the earth has captured in its magnetic trap. Solar plasma is a gaseous, electrically neutral mixture of positive and negative ions that the sun spews out from convulsed regions on its surface.

  2. Radiation smog

    International Nuclear Information System (INIS)

    Spurny, Z.

    1988-01-01

    The principle is described of the production of radiation smog resulting from radioactive emisions. The differences are discussed in the contamination over the territory of Czechoslovakia following the Chernobyl accident. The higher surface contamination of industrial areas recorded after the accident can be explained by electroprecipitation of industrial impurities with the radicals and ions of the radioactive cloud. (E.S.). 3 figs., 16 refs

  3. Radiation Hard and Self Healing Substrate Agnostic Nanocrystalline ZnO Thin Film Electronics

    Science.gov (United States)

    2017-04-14

    PERSON HONG, SENG 19b.  TELEPHONE NUMBER (Include area code ) 315-229-3519 Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18 Page 1 of...of radiation induced changes in the electronic properties of metal-oxide (M-O) semiconductors with s-orbital dominated conduction bands. s-orbital... conduction band materials are particularly interesting because they offer potential for radiation hardness and self-healing very different (and

  4. UV-VUV synchrotron radiation spectroscopy of NiWO4

    Science.gov (United States)

    Kuzmin, A.; Pankratov, V.; Kalinko, A.; Kotlov, A.; Shirmane, L.; Popov, A. I.

    2016-07-01

    Photoluminescence and excitation spectra of microcrystalline and nanocrystalline nickel tungstate (NiWO4) were measured using UV-VUV synchrotron radiation source. The origin of the bands is interpreted using comparative analysis with isostructural ZnWO4 tungstate and based on the results of recent first-principles band structure calculations. The influence of the local atomic structure relaxation and of Ni2+ intra-ion d-d transitions on the photoluminescence band intensity are discussed.

  5. Radiation pager

    International Nuclear Information System (INIS)

    Warren, J.L.; Vadnais, K.G.

    1998-01-01

    Methods of interdicting nuclear materials to date have favored the use of large portal detectors at choke points, or hand carried instruments used by trained personnel for conducting spot searches. Although these methods are effective in some instances, it is often impractical to insert choke points at busy traffic areas, and it is not cost effective to maintain a force of skilled operators whose focus is nuclear interdiction. Recent technology developments are causing profound changes in the philosophy and methods employed for interdicting nuclear materials. Breakthrough advances in the miniaturization of detectors and low power electronics have made possible a new class of small gamma-ray radiation detectors, roughly the size of a message pager, with unprecedented sensitivity for their size. These instruments, named Radiation Pagers TM , are ideally suited for use by untrained individual law enforcement personnel and emergency responders in the course of their regular duties. New tactics that utilize a radiation detector worn by every officer are creating a moving curtain of detection with a significantly higher likelihood of locating illicit nuclear contraband. These individual detectors also provide each officer with a high level of confidence that they are not being unknowingly irradiated in the course of their work. (author)

  6. Therapeutic possibilities of electromagnetic radiation of very high frequency

    OpenAIRE

    Chwaleba, Augustyn; Jatsunenko, Anatoly; Kamkov, V.; Szczurko, Jan; Szmitkowski, Józef; Yatsunenko, Sergey; Wilczkowski, Stefan

    2012-01-01

    Virtually the entire spectrum of electromagnetic radiation is applied in medicine, with the fact tha t the radiation in the frequency band from 30 GHz to 300 GHz has been used recently. The authors developed (and continue to improve) the therapeutic method that uses electromagnetic fields of very high frequency (vhf) in the band from 40 GHz to 70 GHz and sublow intensity the power flux density does not exceed 1 μW / cm ². This field acts informationally on cells, causing the reactivation proc...

  7. Band head spin assignment of superdeformed bands in 133Pr using two-parameter formulae

    Science.gov (United States)

    Sharma, Honey; Mittal, H. M.

    2018-03-01

    The two-parameter formulae viz. the power index formula, the nuclear softness formula and the VMI model are adopted to accredit the band head spin (I0) of four superdeformed rotational bands in 133Pr. The technique of least square fitting is used to accredit the band head spin for four superdeformed rotational bands in 133Pr. The root mean deviation among the computed transition energies and well-known experimental transition energies are attained by extracting the model parameters from the two-parameter formulae. The determined transition energies are in excellent agreement with the experimental transition energies, whenever exact spins are accredited. The power index formula coincides well with the experimental data and provides minimum root mean deviation. So, the power index formula is more efficient tool than the nuclear softness formula and the VMI model. The deviation of dynamic moment of inertia J(2) against the rotational frequency is also examined.

  8. Band connectivity for topological quantum chemistry: Band structures as a graph theory problem

    Science.gov (United States)

    Bradlyn, Barry; Elcoro, L.; Vergniory, M. G.; Cano, Jennifer; Wang, Zhijun; Felser, C.; Aroyo, M. I.; Bernevig, B. Andrei

    2018-01-01

    The conventional theory of solids is well suited to describing band structures locally near isolated points in momentum space, but struggles to capture the full, global picture necessary for understanding topological phenomena. In part of a recent paper [B. Bradlyn et al., Nature (London) 547, 298 (2017), 10.1038/nature23268], we have introduced the way to overcome this difficulty by formulating the problem of sewing together many disconnected local k .p band structures across the Brillouin zone in terms of graph theory. In this paper, we give the details of our full theoretical construction. We show that crystal symmetries strongly constrain the allowed connectivities of energy bands, and we employ graph theoretic techniques such as graph connectivity to enumerate all the solutions to these constraints. The tools of graph theory allow us to identify disconnected groups of bands in these solutions, and so identify topologically distinct insulating phases.

  9. Diagnosis and management of early gastric band slip after laparoscopic adjustable gastric banding

    Directory of Open Access Journals (Sweden)

    Mehmet Sertkaya

    2016-05-01

    Full Text Available Laparoscopic adjustable gastric banding (LAGB used to be a very popular bariatric procedure at a certain time for the treatment of obesity as it has many advantages and is associated with low morbidity and mortality rates. Complications are often late and are rarely seen by general surgeons due to the limited number of patients, and physicians should be aware of the symptoms. We present a case of a 40-year-old female patient who underwent LAGB and was admitted for a huge gastric pouch dilatation on postoperative day 5. She had a history of food consumption on the fourth day after surgery. She was diagnosed with early gastric band slippage (EGBS. The band was repositioned and gastrogastric sutures were placed to prevent reprolapse of the band. The EGBS is an immediate postoperative complication. Diagnosis of EGBS can be made with oral contrast X-ray studies, and surgical intervention is necessary.

  10. Electronic pairing mechanism due to band modification in a two-band model: Tc evaluation

    International Nuclear Information System (INIS)

    Mizia, J.; Gorski, G.; Traa, M.R.M.J.

    1997-01-01

    Following the electronic model developed by us previously (Mizia and Romanowski, Mizia) we estimate the superconducting transition temperature in a simple electronic two-band model for materials characterized by a broad superconducting band and a narrow level within the same energy range. A large electron deformation coupling constant and large electron correlation effects are assumed. It is shown that high-temperature superconductivity is entirely possible within a range of reasonable electronic parameters. This model does not assume any artificial interactions to obtain a negative pairing potential. Instead, the negative part of the electronic interaction potential comes from the modification of the electron dispersion relation with growing number of superconducting pairs. Such a modification is possible in soft electronic systems, i.e. in systems partial to band modification due to large internal stresses, strong electronic correlation effects and broad band narrow level charge transfer during the superconducting transition. (orig.)

  11. Correlation of radiative properties of rare earth ions (Pr and Nd ) in ...

    Indian Academy of Sciences (India)

    Unknown

    Optical band gaps; spectroscopic parameters; intensity parameters; radiative lifetimes. 1. Introduction. Generally phosphate ... 1 and 2, respectively. The optical band gap, 'Eopt' values are obtained by extrapo- lation to. 2/1 .... anion and chloride cation and Ω4 and Ω6 parameters indi- cate the rigidity of the host. From the ...

  12. Electromagnetic fields radiated from electrostatic discharges: Theory and experiment

    Science.gov (United States)

    Wilson, Perry F.; Ondrejka, Arthur R.; Ma, Mark T.; Ladbury, John M.

    1988-02-01

    The fields radiated by electrostatic discharges (ESD) are studied both theoretically and experimentally. The ESD spark is modeled theoretically as an electrically short, time dependent, linear dipole situated above an infinite ground plane. Experimentally, sparks of varying voltages are generated by a commercially available simulator and used to excite a number of targets including: (1) the extended inner conductor of a coaxial cable mounted in a ground plane, (2) direct discharges to a ground plane, (3) indirect radiation from a large metal plate, (4) a metal chair over a a ground plane, and (5) a metal trash can. Results show that relatively low-voltage sparks (2 to 4 kV) excite the strongest radiated fields. This suggests that the spark fields can pose a significant interference threat to electronic equipment into the gigahertz range.

  13. Assessment of S-NPP VIIRS band-to-band registration using Earth-scene features

    Science.gov (United States)

    Link, Daniel; Wang, Zhipeng; Xiong, Xiaoxiong

    2017-09-01

    The Visible Infrared Imaging Radiometer Suite (VIIRS) is currently operating onboard the Suomi National Polarorbiting Partnership (S-NPP) spacecraft. VIIRS records Earth imagery with spectral bands ranging from 0.4 to 12.2 micrometers at a combination of resolutions. Five imaging bands (I1-5) have a 375 m spatial resolution at nadir, which is half of the 750 m resolution of the 16 moderate resolution bands (M1-16). These bands are mounted according to their wavelengths at three separate Focal Plane Assemblies (FPA). The proper spatial registration among imaging bands is required to create multi-spectral images and analyses. Measurement of the band-to-band registration (BBR) is a determination of how well these bands are coincident. Using an external target such as the moon has proven to be a valid method and has been thoroughly investigated using VIIRS raw data record (RDR). Calibrated VIIRS radiometric data has been investigated using normalized mutual information (NMI) for BBR and shown stable results, by focusing on high-contrast shoreline sites. However, these results focus on a relatively small number of observations. We have previously reported analyses using earth-scene targets to determine BBR for MODIS instruments. This approach focuses on an African Desert site with high contrast spots generated through agricultural pivot irrigation. Using the near-daily observations provided by the VIIRS instrument, we investigate a large data set and track the BBR stability over the VIIRS mission. We discuss our results and compare them with prelaunch measurements and design specifications.

  14. Transport in bilayer and trilayer graphene: band gap engineering and band structure tuning

    Science.gov (United States)

    Zhu, Jun

    2014-03-01

    Controlling the stacking order of atomically thin 2D materials offers a powerful tool to control their properties. Linearly dispersed bands become hyperbolic in Bernal (AB) stacked bilayer graphene (BLG). Both Bernal (ABA) and rhombohedral (ABC) stacking occur in trilayer graphene (TLG), producing distinct band structures and electronic properties. A symmetry-breaking electric field perpendicular to the sample plane can further modify the band structures of BLG and TLG. In this talk, I will describe our experimental effort in these directions using dual-gated devices. Using thin HfO2 film deposited by ALD as gate dielectric, we are able to apply large displacement fields D > 6 V/nm and observe the opening and saturation of the field-induced band gap Eg in bilayer and ABC-stacked trilayer graphene, where the conduction in the mid gap changes by more than six decades. Its field and temperature dependence highlights the crucial role played by Coulomb disorder in facilitating hopping conduction and suppressing the effect of Eg in the tens of meV regime. In contrast, mid-gap conduction decreases with increasing D much more rapidly in clean h-BN dual-gated devices. Our studies also show the evolution of the band structure in ABA-stacked TLG, in particular the splitting of the Dirac-like bands in large D field and the signatures of two-band transport at high carrier densities. Comparison to theory reveals the need for more sophisticated treatment of electronic screening beyond self-consistent Hartree calculations to accurately predict the band structures of trilayer graphene and graphenic materials in general.

  15. Applications of nuclear radiations

    International Nuclear Information System (INIS)

    Hanagodimath, S.M.

    2012-01-01

    Nuclear radiations are powerful and non destructive tools in industry, medicine, defence, agriculture and research. In the present lecture, the types of nuclear radiations, radiation sources, detection of radiation, uses of radiation, dangers of nuclear radiation and nuclear energy will be discussed. (author)

  16. Perspective of radiation processing

    International Nuclear Information System (INIS)

    Zhang Manwei

    1987-01-01

    The area of the applications of radiation techniques is very wide. This paper only relates to the applications of radiation techniques in industries including radiation chemical industry, radiation processing of foods and environmental protection by radiation, but the nuclear instruments and the instrumentations of radiation are out-side of our study. (author)

  17. Radio-ecological conditions of band coniferous forests

    International Nuclear Information System (INIS)

    Strilchuk, Yu.G.; Osintsev, A.Yu.; Kuzin, D.E.; Bryantseva, N.V.; Tonevitskaya, O.V.; Zhadyranova, A.A.; Kashirskij, V.V.; Korovina, O.Yu.; Lukashenko, S.N.

    2008-01-01

    Full text: Band coniferous forests are located at the right bank of Irtysh river in two oblasts of Kazakhstan - East Kazakhstan and Pavlodar.This is a unique and only forest of this type. Something similar to this natural treasure with climate-regulating, sanitary, soil-protective, water-preserving functions can be found in Canada only. Total area of the band forest comprises 870500 hectares. The forest is mainly presented by pines (Pinus silvestris). These forests are of relict nature and are of great environmental, social and economic value. The band forests located in northern, north-western and western parts of SNTS were subjected several time to radioactive impacts from atmospheric nuclear tests performed at SNTS. Nuclear clouds from 12 ground and 28 atmospheric explosions passed over these territories. Four nuclear tests performed on 29th of August 1949, 29th of July 1955, 7th of August 1962 and 26th of November 1962 resulted in higher radiation dose rates registered on land there. It seems that this particular tests stipulated radioactive contamination of the forests. The first nuclear test performed on 29th of August 1949 resulted in considerable radioactive contamination of the band forests. Contamination was registerd in Novopokrovskij and Beskaragajskij districts of Semipalatinsk oblast as well as in several districts of Altai Territory. The second test that could bring radioactive contamination to the forests was performed on 7th of August 1962 when instead of planned atmospheric explosion, there was achieved surface explosion with comparatively high radioactive contamination of the lands towards Altai Territory. Within the State program ''Forest preservation and expansion of forest in the Republic of Kazakhstan'' there was performed in 2006 a radiological surveying of the lands in pipe forest of near-Irtysh region. There were studied soil and vegetation as well as woods of the band coniferous forests. Part of territory, wherethrough nuclear clouds went

  18. Development of softcopy environment for primary color banding visibility assessment

    Science.gov (United States)

    Min, Byungseok; Pizlo, Zygmunt; Allebach, Jan P.

    2008-01-01

    Fine-pitch banding is one of the most unwanted artifacts in laser electrophotographic (EP) printers. It is perceived as a quasiperiodic fluctuation in the process direction. Therefore, it is essential for printer vendors to know how banding is perceived by humans in order to improve print quality. Monochrome banding has been analyzed and assessed by many researchers; but there is no literature that deals with the banding of color laser printers as measured from actual prints. The study of color banding is complicated by the fact that the color banding signal is physically defined in a three-dimensional color space, while banding perception is described in a one-dimensional sense such as more banding or less banding. In addition, the color banding signal arises from the independent contributions of the four primary colorant banding signals. It is not known how these four distinct signals combine to give rise to the perception of color banding. In this paper, we develop a methodology to assess the banding visibility of the primary colorant cyan based on human visual perception. This is our first step toward studying the more general problem of color banding in combinations of two or more colorants. According to our method, we print and scan the cyan test patch, and extract the banding profile as a one dimensional signal so that we can freely adjust the intensity of banding. Thereafter, by exploiting the pulse width modulation capability of the laser printer, the extracted banding profile is used to modulate a pattern consisting of periodic lines oriented in the process direction, to generate extrinsic banding. This avoids the effect of the halftoning algorithm on the banding. Furthermore, to conduct various banding assessments more efficiently, we also develop a softcopy environment that emulates a hardcopy image on a calibrated monitor, which requires highly accurate device calibration throughout the whole system. To achieve the same color appearance as the hardcopy

  19. A Compact Tri-Band Bandpass Filter with High Out-of-Band Rejection

    Directory of Open Access Journals (Sweden)

    M. Abdul-Niby

    2017-08-01

    Full Text Available This paper presents a planar tri-band bandpass filter with high out-of-band rejection over a wide band. The filter is based on two pairs of λ/4 resonators embedded inside an open loop ring resonator without any size increase, where each pair of resonators are electromagnetically coupled to each other and the feedlines. This results in the excitations of passbands, where the first passband is generated by the open loop resonators. The second and the third passbands are excited by λ/4 resonators. The proposed technique provides sufficient degrees of freedom to control the center frequency and bandwidth of the three passbands independently. In addition, the six transmission zeros created around the passbands results in a tri-band filter with high selectivity, sharp 3 dB cut-off frequency, high isolation, low passband insertion-loss and high out-of-band harmonic rejection across an ultra-broadband frequency range up to 17 GHz. The proposed technique has the ability to switch from triple to dual band by removing one pair of the inner resonators. Design methodology and simulation results of the filter are provided.

  20. Wide band interferometry for thickness measurement

    Science.gov (United States)

    Costantino, Santiago; Martinez, Oscar E.; Torga, Jorge R.

    2003-04-01

    In this work we present the concept of wide band interferometry as opposed to white-light interferometry to introduce a thickness measurement method that gains precision when the bandwidth is reduced to an adequate compromise in order to avoid the distortions arising from the material dispersion. The use of the widest possible band is a well established dogma when the highest resolution is desired in distance measurements with white-light interferometry. We will show that the dogma falls when thickness measurements must be carried out due to material dispersion. In fact the precise knowledge of the frequency dependence of the refractive index is essential for adequate thickness retrieval from the optical experiments. The device we present is also useful to obtain the group refractive index that is necessary to calculate the absolute thickness value. As an example, we show the spreading of a silicone oil on a reference surface in real time.