WorldWideScience

Sample records for carrier concentration compensation

  1. Executive Compensation Concentration and Institutional Ownership Power

    OpenAIRE

    Wei Li; Tingting Guo

    2015-01-01

    In this paper, we examine whether institutional shareholders prefer concentrated or dispersed executive compensation structure. To address this question, we study the relationship between executive compensation concentration and institutional ownership power because institutional investors can influence executive compensation more when they have more power. We measure institutional ownership power using institutional ownership level and institutional ownership concentration. We find a signifi...

  2. Deep-level transient spectroscopy of low-free-carrier-concentration n-GaN layers grown on freestanding GaN substrates: Dependence on carbon compensation ratio

    Science.gov (United States)

    Tanaka, Takeshi; Shiojima, Kenji; Mishima, Tomoyoshi; Tokuda, Yutaka

    2016-06-01

    Electron traps in n-GaN layers with a relatively low-free-carrier-concentration of approximately 1 × 1016 cm‑3 were characterized by deep-level transient spectroscopy. Sample layers were grown by metal organic chemical vapor deposition with a thickness of 12 µm on freestanding GaN substrates, and were doped with both silicon and carbon. The measurement results showed a reduction in the density of carbon-related electron traps at an energy level of E C ‑0.40 eV in GaN on GaN samples, compared with GaN on SiC samples. It was also observed that the doping of carbon significantly suppressed electron traps at E C ‑0.61 eV, which was associated with the nitrogen antisite. Consequently, the possibility of minimizing all of the electron traps located between E C ‑0.19 and ‑0.89 eV in n-GaN was demonstrated by controlling the carbon doping in the nitrogen site.

  3. Ownership Concentration, Top Management and Board Compensation

    Directory of Open Access Journals (Sweden)

    Marcos Barbosa Pinto

    2013-05-01

    Full Text Available The degree of ownership concentration may influence executive and board compensation (Bebchuk & Fried, 2003. This article analyzes this relationship. Detailed information about top management and board compensation became available starting in 2010 through new Securities Commission filings. Linear regression models applied to a sample of 315 Brazilian companies traded on the national exchange indicate a negative and statistically significant economic correlation between executive compensation and the degree of ownership concentration. Ceteris paribus, companies with a lower degree of ownership concentration pay higher compensation to top executives. Family controlled companies pay more to their chief executive, but not to the managerial team as a whole, and the compensation of directors increases with a greater proportion of control group members or their relatives on the board. There was support for the Managerial Power Hypothesis in companies with a lower degree of ownership concentration and for the extraction of private benefits in companies where it is greater.

  4. Transport properties of Ru-doped La1.85Sr0.15CuO4 and the effect of carrier concentration compensation

    International Nuclear Information System (INIS)

    This paper is a study of the structure and transport properties of Ru-doped La1.85Sr0.15CuO4. It is found that Ru substitution for Cu has two effects. (1) Ru doping introduces disorder into the system, which causes a metal-insulator transition with high localization. (2) There is a hole-filling effect due to the valence of the Ru ion being higher than that of the Cu ion. Increase of the strontium content could compensate for the imbalance of valence caused by doping with the high-valence Ru ion. A universal curve for Tc versus the number of holes per Cu site is observed for the La2-ySryCu1-xRuxO4 system, indicating that a rigid-band model holds and Tc correlates with features in the density of states, such as a Van Hove singularity

  5. Suppression of Compensating Native Defect Formation During Semiconductor Processing via Excess Carriers

    Energy Technology Data Exchange (ETDEWEB)

    Alberi, Kirstin; Scarpulla, M. A.

    2016-06-21

    In many semiconductors, compensating defects set doping limits, decrease carrier mobility, and reduce minority carrier lifetime thus limiting their utility in devices. Native defects are often responsible. Suppressing the concentrations of compensating defects during processing close to thermal equilibrium is difficult because formation enthalpies are lowered as the Fermi level moves towards the majority band edge. Excess carriers, introduced for example by photogeneration, modify the formation enthalpy of semiconductor defects and thus can be harnessed during crystal growth or annealing to suppress defect populations. Herein we develop a rigorous and general model for defect formation in the presence of steady-state excess carrier concentrations by combining the standard quasi-chemical formalism with a detailed-balance description that is applicable for any defect state in the bandgap. Considering the quasi-Fermi levels as chemical potentials, we demonstrate that increasing the minority carrier concentration increases the formation enthalpy for typical compensating centers, thus suppressing their formation. This effect is illustrated for the specific example of GaSb. While our treatment is generalized for excess carrier injection or generation in semiconductors by any means, we provide a set of guidelines for applying the concept in photoassisted physical vapor deposition.

  6. O2 sensing dynamics of BiFeO3 nanofibers: effect of minor carrier compensation.

    Science.gov (United States)

    Sobhan, Mushtaq; Xu, Qiang; Katoch, Akash; Anariba, Franklin; Kim, Sang Sub; Wu, Ping

    2015-05-01

    In this paper we investigate O(2) sensing dynamics in BiFeO(3) (BFO) nanofibers at various concentrations and temperatures, by using a combined experiment and computer simulation approach. Samples of pristine BFO, Ni-doped BFO, and Pb-doped BFO nanofibers were prepared. By incorporating Ni and Pb, additional acceptor states are introduced in BFO. Density functional theory calculations show that Ni prefers to substitute Fe site while Pb substitutes Bi site, resulting in a new deep donor originating from Ni interstitial defects, along with oxygen vacancies (V(o)). We find that both the sensing response and recovery time are shorter in samples made of pristine BFO nanofibers than in Ni- and Pb-doped nanofiber samples. We interpret the observed sensing dynamics through charge transport theory of the major (acceptors) and minor (donors) carriers, and found that the minor carrier compensation plays a significant role in determining the response and recovery time of the sensor device. This minor carrier compensation charge transport mechanism will provide new insights into more robust sensor development strategies, and into the research of ion-electron coupling in chemical dynamics of semiconductors. PMID:25850830

  7. Realization of LOS (Line of Sight) stabilization based on reflector using carrier attitude compensation method

    Science.gov (United States)

    Mao, Yao; Tian, Jing; Ma, Jia-guang

    2015-02-01

    The techonology of LOS stabilization is widely applicated in moving carrier photoelectric systems such as shipborne, airborne and so on. In application situations with compact structure, such as LOS stabilization system of unmanned aerial vehicle, LOS stabilization based on reflector is adopted, and the detector is installed on the carrier to reduce the volume of stabilized platform and loading weight. However, the LOS deflection angle through reflector and the rotation angle of the reflector has a ratio relation of 2:1, simple reflector of stable inertial space can not make the optical axis stable. To eliminate the limitation of mirror stabilizing method, this article puts forward the carrier attitude compensation method, which uses the inertial sensor installed on the carrier to measure the attitude change of the carrier, and the stabilized platform rotating half of the carrier turbulence angle to realize the LOS stabilization.

  8. Transport properties of Ru-doped La sub 1 sub . sub 8 sub 5 Sr sub 0 sub . sub 1 sub 5 CuO sub 4 and the effect of carrier concentration compensation

    CERN Document Server

    Xiong, Y M; Luo, X G; Zhang, H T; Wang, C H; Li, S Y; Chen, X H

    2003-01-01

    This paper is a study of the structure and transport properties of Ru-doped La sub 1 sub . sub 8 sub 5 Sr sub 0 sub . sub 1 sub 5 CuO sub 4. It is found that Ru substitution for Cu has two effects. (1) Ru doping introduces disorder into the system, which causes a metal-insulator transition with high localization. (2) There is a hole-filling effect due to the valence of the Ru ion being higher than that of the Cu ion. Increase of the strontium content could compensate for the imbalance of valence caused by doping with the high-valence Ru ion. A universal curve for T sub c versus the number of holes per Cu site is observed for the La sub 2 sub - sub y Sr sub y Cu sub 1 sub - sub x Ru sub x O sub 4 system, indicating that a rigid-band model holds and T sub c correlates with features in the density of states, such as a Van Hove singularity.

  9. A carrier leakage calibration and compensation technique for wideband wireless transceiver

    International Nuclear Information System (INIS)

    A carrier leakage calibration and compensation technique based on digital baseband for a wideband wireless communication transceiver is proposed. The digital baseband transmits a calibration signal, samples the signal which passes through the transmitter path and the calibration loop in the RF chip, measures the carrier leakage by analyzing the sampled data and compensates it. Compared with a self-calibration technique in the RF chip, the proposed technique saves area and power consumption for the wireless local area network (WLAN) solution. This technique has been successfully used for 802.1 1n system and satisfies the requirement of the standard by achieving over 50 dB carrier leakage suppression. (semiconductor integrated circuits)

  10. Electrical mechanisms for carrier compensation in homoepitaxial nonpolar m-ZnO doped with nitrogen

    Science.gov (United States)

    Kurtz, A.; Hierro, A.; Lopez-Ponce, M.; Tabares, G.; Chauveau, J. M.

    2016-03-01

    By combining photoluminescence, capacitance-voltage profiling and deep level optical spectroscopy, the optical and electrical signatures of the deep levels induced by N in MBE-grown homoepitaxial m-ZnO layers are identified and correlated to different physical origins. The films are electrically compensated, with carrier concentrations that decrease from ˜1 · 1016 cm-3 to ˜2 · 1015 cm-3 as a result of increasing N incorporation. Regardless of the presence of N, an intrinsic trap is found in all films at EV + 0.25 eV, most likely related to VZn defects. More interestingly, N induces three new deep levels close to the valence band whose bandgap position is electrically observed to be at EV + 0.48 eV, EV + 0.17 eV and EV + 0.12 eV. The deepest trap at EV + 0.48 eV correlates well with a N-induced level observed in previous studies on both ZnMgO and ZnO films. The EV + 0.17 eV trap behaves as a minority (hole) carrier trap, and can be uniquely correlated with the acceptor level involved in the N-induced DAP emission observed in the photoluminescence spectra. Finally, the shallowest level at EV + 0.12 eV shows an electrical signature completely distinguishable from the EV + 0.17 eV level, and dominates the deep level spectra after N-incorporation with a trap concentration of ˜1.2 · 1015 cm-3.

  11. Profiling the local carrier concentration across a semiconductor quantum dot

    Energy Technology Data Exchange (ETDEWEB)

    Walrath, J. C.; Lin, Yen-Hsiang [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Huang, S. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States); Goldman, R. S., E-mail: rsgold@umich.edu [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States); Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2015-05-11

    We profile the local carrier concentration, n, across epitaxial InAs/GaAs quantum dots (QDs) consisting of 3D islands on top of a 2D alloy layer. We use scanning thermoelectric microscopy to measure a profile of the temperature gradient-induced voltage, which is converted to a profile of the local Seebeck coefficient, S. The S profile is then converted to a conduction band-edge profile and compared with Poisson-Schrodinger band-edge simulations. Our combined computational-experimental approach suggests a reduced carrier concentration in the QD center in comparison to that of the 2D alloy layer. The relative roles of free carrier trapping and/or dopant expulsion are discussed.

  12. Effects of carrier phase estimation on front-end IQ mismatch compensation in mode division multiplexed MIMO coherent receiver

    Science.gov (United States)

    Chung, Hwan Seok; Chang, Sun Hyok; Kim, Kwangjoon; Lee, Jong Hyun

    2014-01-01

    The effects of carrier phase estimation on IQ mismatch compensation are investigated and compared for coherent MIMO optical receiver. We investigate the impacts of phase IQ mismatch on required optical signal-to-noise ratio (OSNR) for coherent MIMO detection. The impacts of number of modes and analog-to-digital converter (ADC) resolution are also evaluated. The results show that decision-directed carrier phase estimator could compensate significant amount of IQ mismatch without employing additional compensation technique, and relaxes requirement of ADC resolution.

  13. Comprehensive study of CD compensation and carrier phase estimation in optical communication systems influenced by equalization enhanced phase noise

    CERN Document Server

    Xu, Tianhua; Popov, Sergei; Li, Jie; Sergeyev, Sergey; Friberg, Ari T; Liu, Tiegen; Zhang, Yimo

    2016-01-01

    The performance of long-haul coherent optical fiber transmission system is significantly affected by the equalization enhanced phase noise (EEPN), due to the interaction between the electronic dispersion compensation (EDC) and the laser phase noise. In this paper, we present a comprehensive study on different chromatic dispersion (CD) compensation and carrier phase recovery (CPR) approaches, in the n-level phase shift keying (n-PSK) and the n-level quadrature amplitude modulation (n-QAM) coherent optical transmission systems, considering the impacts of EEPN. Four CD compensation methods are considered: the time-domain equalization (TDE), the frequency-domain equalization (FDE), the least mean square (LMS) adaptive equalization are applied for EDC, and the dispersion compensating fiber (DCF) is employed for optical dispersion compensation (ODC). Meanwhile, three carrier phase recovery methods are also involved: a one-tap normalized least mean square (NLMS) algorithm, a block-wise average (BWA) algorithm, and a...

  14. A direct-conversion WLAN transceiver baseband with DC offset compensation and carrier leakage reduction

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Fang; Yan Jun; Ma Heping; Shi Yin [Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China); Foster, Dai Fa, E-mail: fyuan@sci-inc.com.c [Department of Electrical and Computer Engineering, Auburn University, Auburn, AL 36849-5201 (United States)

    2010-10-15

    A dual-band direct-conversion WLAN transceiver baseband compliant with the IEEE 802.11a/b/g standards is described. Several critical techniques for receiver DC offset compensation and transmitter carrier leakage rejection calibration are presented that enable the direct-conversion architecture to meet all WLAN specifications. The receiver baseband VGA provides 62 dB gain range with steps of 2 dB and a DC offset cancellation circuit is introduced to remove the offset from layout and self-mixing. The calibration loop achieves constant high-pass pole when gain changes; and a fast response time by programming the pole to 1 MHz during preamble and to 30 kHz during receiving data. The transmitter baseband employs an auto-calibration loop with on-chip AD and DA to suppress the carrier leakage, and AD can be powered down after calibration to save power consumption. The chip consumes 17.52 mA for RX baseband VGA and DCOC, and 8.3 mA for TX carrier leakage calibration (5.88 mA after calibration) from 2.85 V supply. Implemented in a 0.35 {mu}m SiGe technology, they occupy 0.68 mm{sup 2} and 0.18 mm{sup 2} die size respectively. (semiconductor integrated circuits)

  15. A direct-conversion WLAN transceiver baseband with DC offset compensation and carrier leakage reduction

    International Nuclear Information System (INIS)

    A dual-band direct-conversion WLAN transceiver baseband compliant with the IEEE 802.11a/b/g standards is described. Several critical techniques for receiver DC offset compensation and transmitter carrier leakage rejection calibration are presented that enable the direct-conversion architecture to meet all WLAN specifications. The receiver baseband VGA provides 62 dB gain range with steps of 2 dB and a DC offset cancellation circuit is introduced to remove the offset from layout and self-mixing. The calibration loop achieves constant high-pass pole when gain changes; and a fast response time by programming the pole to 1 MHz during preamble and to 30 kHz during receiving data. The transmitter baseband employs an auto-calibration loop with on-chip AD and DA to suppress the carrier leakage, and AD can be powered down after calibration to save power consumption. The chip consumes 17.52 mA for RX baseband VGA and DCOC, and 8.3 mA for TX carrier leakage calibration (5.88 mA after calibration) from 2.85 V supply. Implemented in a 0.35 μm SiGe technology, they occupy 0.68 mm2 and 0.18 mm2 die size respectively. (semiconductor integrated circuits)

  16. High resistivity in undoped CdTe: carrier compensation of Te antisites and Cd vacancies

    International Nuclear Information System (INIS)

    In this paper, we focus on the high resistivity of intentionally undoped CdTe, where the most prevalent defects are Cd vacancies and Te antisites. Our calculated formation energies lead to the conclusion that the Fermi energy of undoped CdTe is at midgap due to carrier compensation of Te antisites and Cd vacancies, which explains the experimentally observed high resistivity. We use density functional theory with the hybrid functional of Heyd, Scuseria and Ernzerhof (HSE06) and show that the proper description of the native defects in general fails using the local density approximation (LDA) instead of HSE06. We conclude that LDA is insufficient to understand the high resistivity of undoped CdTe. We calculate the neutral and double acceptor state of the Te antisite to be intrinsic DX-centers. (paper)

  17. Free-charge carrier parameters of n-type, p-type and compensated InN:Mg determined by infrared spectroscopic ellipsometry

    International Nuclear Information System (INIS)

    Infrared spectroscopic ellipsometry is applied to investigate the free-charge carrier properties of Mg-doped InN films. Two representative sets of In-polar InN grown by molecular beam epitaxy with Mg concentrations ranging from 1.2 × 1017 cm−3 to 8 × 1020 cm−3 are compared. P-type conductivity is indicated for the Mg concentration range of 1 × 1018 cm−3 to 9 × 1019 cm−3 from a systematic investigation of the longitudinal optical phonon plasmon broadening and the mobility parameter in dependence of the Mg concentration. A parameterized model that accounts for the phonon–plasmon coupling is applied to determine the free-charge carrier concentration and mobility parameters in the doped bulk InN layer as well as the GaN template and undoped InN buffer layer for each sample. The free-charge carrier properties in the second sample set are consistent with the results determined in a comprehensive analysis of the first sample set reported earlier [Schöche et al., J. Appl. Phys. 113, 013502 (2013)]. In the second set, two samples with Mg concentration of 2.3 × 1020 cm−3 are identified as compensated n-type InN with very low electron concentrations which are suitable for further investigation of intrinsic material properties that are typically governed by high electron concentrations even in undoped InN. The compensated n-type InN samples can be clearly distinguished from the p-type conductive material of similar plasma frequencies by strongly reduced phonon plasmon broadening. - Highlights: • Optical determination of free-charge carrier parameters in In-polar InN:Mg films • Identification of conductivity type and determination of concentration and mobility • Similar trends for two independent sample sets showing general Mg-doping behavior • Identification of compensated n-type samples with very low electron concentrations • Confirmation of different phonon plasmon broadening for holes and electrons

  18. Fiber Bragg Grating Sensor Array System Based on Digital Phase Generated Carrier Demodulation and Reference Compensation Method

    Institute of Scientific and Technical Information of China (English)

    Jun He; Fang Li; Hao Xiao; Yu-Liang Liu

    2008-01-01

    A novel fiber Bragg grating (FBG) sensor array system based on digital phase generated carrier (PGC) demodulation and reference compensation method is proposed and set up. Experimental results confirm that the digital PGC demodulation can be used for wavelength-division-multiplexed FBG sensor array and the reference compensation method can reduce the environmental interference by approximately 40 dB in the frequency range from 20 Hz to 2 kHz. The minimum detectable wavelength-shift of the sensor system is 1×10-3 pm/Hz1/2.

  19. Multi-user interference cancellation schemes for carrier frequency offset compensation in uplink OFDMA

    DEFF Research Database (Denmark)

    Nguyen, Huan Cong; De Carvalho, Elisabeth; Prasad, Ramjee

    2014-01-01

    Each user in the uplink of an Orthogonal Frequency Division Multiple Access (OFDMA) system may experience a different carrier frequency offset (CFO). These uncorrected CFOs destroy the orthogonality among subcarriers, causing inter-carrier interference and multi-user interference, which degrade t...... cancellation techniques for Orthogonal Frequency Division Multiple Access (OFDMA) available in literature with comparable or lower complexity....

  20. Concentration increases in the isotopic germanium carrier solutions inferred from solution weights

    International Nuclear Information System (INIS)

    Concentration increases in the isotopic germanium carrier solutions via evaporation would produce weight losses in the carrier solutions. Since the bottle containing each carrier is usually weighed before and after the removal of carrier for a given run, the possibility exists of finding evidence for increasing carrier concentration in this record. With few exceptions the weighings were performed on the same top-loading balance in the external chemistry lab. The primary purpose was to monitor carrier usage, not to look for evidence for increasing carrier concentration. However, in order to look for this evidence, it is necessary only to compare the weights of the closed bottles between the times of carrier removal. This comparison has been performed and is reported here. Bear in mind that there is some evidence that the bottle containing carrier was not always weighted in the same way (e.g. perhaps a plastic bag was not removed from the bottle or the bottle cap was removed before weighing). Another possible source of weighing errors is the occasional buildup of static charges, especially on dry winter days. Such problems of static electricity were easily recognized and overcome. For the most part, the resulting record agrees with the assumption that the weighings were performed consistently. Carrier solution data were analyzed and a correction factor was calculated

  1. Effect of carrier concentration on transportation of thorium from nitric acid medium across supported liquid membrane using Aliquat 336 as carrier

    International Nuclear Information System (INIS)

    Thorium transportation across supported liquid membrane from nitric acid as a function of carrier concentration and feed acidity is studied. Thorium transportation increased with nitric acid concentration till 5 M feed acidity and decreased after wards. Thorium permeability coefficient varies greatly as a function of carrier concentration depending on the feed acidity conditions. (author)

  2. Er-doped concentric-cores optical fiber for simultaneous amplification and compensation of positive dispersion

    Institute of Scientific and Technical Information of China (English)

    Pramod R. Watekar; M. L. N. Goswami; H. N. Acharya; J. C. Biswas; B. P. Pal

    2004-01-01

    The Er-doped concentric-cores dispersion compensating fiber (EDDCF) has been demonstrated. The rare earth has been doped as a ring around the inner core. We have obtained 14-dB gain at 1550 nm (using the optical fiber network where amplification as well as negative dispersion are necessary.

  3. Carrier recombination effects in strain compensated quantum dot stacks embedded in solar cells

    OpenAIRE

    Alonso Alvarez, Diego; González Taboada, Alfonso; Ripalda Cobián, Jose María; Alén Millán, Benito; González Diez, M. Yolanda; González Soto, Luisa; García Martín, Jorge Miguel; Martí Vega, Antonio; Luque López, Antonio; Briones Fernández-Pola, Fernando; Sanchez, A. M.; Molina Rubio, Sergio Ignacio

    2008-01-01

    In this work we report the stacking of 50 InAs/GaAs quantum dot layers with a GaAs spacer thickness of 18 nm using GaP monolayers for strain compensation. We find a good structural and optical quality of the fabricated samples including a planar growth front across the whole structure, a reduction in the quantum dot size inhomogeneity, and an enhanced thermal stability of the emission. The optimized quantum dot stack has been embedded in a solar cell structure and we discuss the benefits and ...

  4. Profiling the local carrier concentration and dopant distribution across a semiconductor quantum dot

    Science.gov (United States)

    Walrath, J. C.; Chang, A. S.; Lin, Y. H.; Huang, S.; Goldman, R. S.

    We profile the local carrier concentration, n, across epitaxial InAs/GaAs quantum dots (QDs) consisting of 3D islands on top of a 2D alloy layer. We use scanning thermoelectric microscopy to profile the temperature gradient-induced voltage, which is converted to a profile of the local Seebeck coefficient, S. The S profile is then converted to a conduction band-edge profile and compared with Poisson-Schrodinger band-edge simulations. Our combined computational-experimental approach suggests a reduced carrier concentration in the QD center in comparison to that of the 2D alloy layer. We further use 3D atom probe tomography, which enables 3D imaging with a few Angstrom resolution, to profile the distribution of Si dopants. We discuss the correlation between the Si dopant distribution and the observed carrier concentration profile.

  5. Home built equipment for measuring Hall coefficient and charge carrier concentration, mobility and resistivity

    DEFF Research Database (Denmark)

    Borup, Kasper Andersen; Christensen, Mogens; Blichfeld, Anders Bank; Johnsen, Simon; Toberer, Eric; Snyder, G. Jeffrey

    2011-01-01

    system, the Quantum Design, Physical Properties Measurement System (PPMS). Measurements on samples with different resistivity and charge carrier concentration will be shown, covering both ends of the interval of samples we are able to measure as well as the range normally observed for thermoelectrics......We present here a home built setup for measuring the specific resistivity, hall coefficient, and charge carrier concentration and mobility at elevated temperatures. The system is optimized for measurements of samples ranging between doped semiconductors and high resistivity metals and uses the van...

  6. Estimation of background carrier concentration in fully depleted GaN films

    Science.gov (United States)

    Chandrasekar, Hareesh; Singh, Manikant; Raghavan, Srinivasan; Bhat, Navakanta

    2015-11-01

    Buffer leakage is an important parasitic loss mechanism in AlGaN/GaN high electron mobility transistors (HEMTs) and hence various methods are employed to grow semi-insulating buffer layers. Quantification of carrier concentration in such buffers using conventional capacitance based profiling techniques is challenging due to their fully depleted nature even at zero bias voltages. We provide a simple and effective model to extract carrier concentrations in fully depleted GaN films using capacitance-voltage (C-V) measurements. Extensive mercury probe C-V profiling has been performed on GaN films of differing thicknesses and doping levels in order to validate this model. Carrier concentrations as extracted from both the conventional C-V technique for partially depleted films having the same doping concentration, and Hall measurements show excellent agreement with those predicted by the proposed model thus establishing the utility of this technique. This model can be readily extended to estimate background carrier concentrations from the depletion region capacitances of HEMT structures and fully depleted films of any class of semiconductor materials.

  7. Sorption of radioiodine at different soil biomass content and carrier iodine concentrations

    International Nuclear Information System (INIS)

    In previous experiments a good correlation between Kd-values for I-125 and artificially decreased and increased biomass between 4% and 136% of its original content was found. Further increase of biomass was ineffective, indicating the exhaustion of the radioiodine as substrate, applied at very low concentrations (≅ 10-11 mol I-.l-1). To test this assumption Kd-values in soil samples of a chernozem with different biomass-levels and with carrier iodine (KI) at concentrations between 10-8 and 10-3 mol I-.l-1 were determined. The sorption behaviour of radioiodine at carrier concentrations between 10-8 and 10-5 mol I-.l-1 applied in bidistilled water in this experiment was similar. (orig./DG)

  8. Photoneutron compensating method for boric acid concentration measuring instrument in heavy water moderated reactor

    International Nuclear Information System (INIS)

    In a boric acid concentration measuring instrument in a heavy water moderated reactor, a portion of γ-ray from Na-24 and Mn-56 is reacted with heavy water to form photoneutrons. The photoneutrons cause errors in the measurement for B-10 concentration. Then, in the present invention, a sample liquid containing photoneutron sources is supplied during normal measurement and a sample liquid removed with the photoneutron sources by passing through an ion exchange resin tower is supplied upon calibration of the measuring instrument. Then, the extent for the of effect of neutron sources and γ-nuclides is obtained by calculation from the measuring value to calibration the extent of the photoneutrons. Further, a method of using a counter tube having a Cd filter is used in combination during normal measurement to enable continuous measurement without exchanging the sample liquid. Accordingly, the influence of photoneutrons can be compensated and boric acid concentration can be measured at high accuracy. (N.H.)

  9. Characterization of carrier concentration in CIGS solar cells by scanning capacitance microscopy

    International Nuclear Information System (INIS)

    Thin films of copper indium gallium selenide (CIGS) designed for highly efficient solar cell material were investigated to characterize the two-dimensional carrier distribution using scanning capacitance microscopy (SCM). We optimized a preparation method of the cross-section samples and concluded that bevel polishing by 25° to 30° was effective for crumbly polycrystalline materials such as CIGS, so as to provide not the surface property of cracked crystalline grains but the cross-section property of individual cut grains. Because of improvement in this preparation procedure, changes in carrier distribution have been observed directly in the active CIGS layer before and after turning on a 100 W halogen lamp irradiation. A calibration curve between carrier concentration N and SCM's dC/dV signals was applied for qualitatively calculating relative values of N in CIGS. Increased carrier concentration peaks on the grains were estimated to become about three times as high as those with the light on. (paper)

  10. Quantifying charge carrier concentration in ZnO thin films by Scanning Kelvin Probe Microscopy

    OpenAIRE

    C. Maragliano; Lilliu, S.; M. S. Dahlem; Chiesa, M.; SOUIER, T.; Stefancich, M.

    2014-01-01

    In the last years there has been a renewed interest for zinc oxide semiconductor, mainly triggered by its prospects in optoelectronic applications. In particular, zinc oxide thin films are being widely used for photovoltaic applications, in which the determination of the electrical conductivity is of great importance. Being an intrinsically doped material, the quantification of its doping concentration has always been challenging. Here we show how to probe the charge carrier density of zinc o...

  11. Concentration dependence of the transport energy level for charge carriers in organic semiconductors

    Science.gov (United States)

    Oelerich, J. O.; Huemmer, D.; Weseloh, M.; Baranovskii, S. D.

    2010-10-01

    The concept of the transport energy (TE) has proven to be one of the most powerful theoretical approaches to describe charge transport in organic semiconductors. In the recent paper L. Li, G. Meller, and H. Kosina [Appl. Phys. Lett. 92, 013307 (2008)] have studied the effect of the partially filled localized states on the position of the TE level. We show that the position of the TE is essentially different to the one suggested by L. Li, G. Meller, and H. Kosina [Appl. Phys. Lett. 92, 013307 (2008)] We further modify the standard TE approach taking into account the percolation nature of the transport path. Our calculations show that the TE becomes dependent on the concentration of charge carriers n at much higher n values than those, at which the carrier mobility already strongly depends on n. Hence the calculations of the concentration-dependent carrier mobility cannot be performed within the approach, in which only the concentration dependence of the TE is taken into account.

  12. The depth-profiled carrier concentration and scattering mechanism in undoped GaN film grown on sapphire

    OpenAIRE

    Fung, S; Beling, CD; Ling, CC; Xu, SJ; Huang, Y.; Chen, XD; Wei, ZF; Zhi, CY

    2004-01-01

    The carrier concentration and scattering mechanism in undoped GaN film grown on sapphire were investigated. The film was grown on sapphire using metal organic chemical vapor deposition (MOCVD). Confocal micro-Raman spectroscopic measurements and temperature-dependant Hall (TDH) measurements were performed for the study of the depth distribution of the carrier density across the GaN film. The existence of a nonuniform spatial distribution of free carriers in the film with a highly conductive l...

  13. DNA Duplex Length and Salt Concentration Dependence of Enthalpy−Entropy Compensation Parameters for DNA Melting

    KAUST Repository

    Starikov, E. B.

    2009-08-20

    Systematical differential calorimetry experiments on DNA oligomers with different lengths and placed in water solutions with various added salt concentrations may, in principle, unravel important information about the structure and dynamics of the DNA and their water-counterion surrounding. With this in mind, to reinterpret the most recent results of calorimetric experiments on DNA oligomers of such a kind, the recent enthalpy-entropy compensation theory has been used. It is demonstrated that the application of the latter could enable direct estimation of thermodynamic parameters of the microphase transitions connected to the changes in DNA dynamical regimes versus the length of the biopolymers and the ionic strengths of their water solutions, and this calls for much more systematical experimental and theoretical studies in this field. © 2009 American Chemical Society.

  14. DNA duplex length and salt concentration dependence of enthalpy-entropy compensation parameters for DNA melting.

    Science.gov (United States)

    Starikov, E B; Nordén, Bengt

    2009-08-20

    Systematical differential calorimetry experiments on DNA oligomers with different lengths and placed in water solutions with various added salt concentrations may, in principle, unravel important information about the structure and dynamics of the DNA and their water-counterion surrounding. With this in mind, to reinterpret the most recent results of calorimetric experiments on DNA oligomers of such a kind, the recent enthalpy-entropy compensation theory has been used. It is demonstrated that the application of the latter could enable direct estimation of thermodynamic parameters of the microphase transitions connected to the changes in DNA dynamical regimes versus the length of the biopolymers and the ionic strengths of their water solutions, and this calls for much more systematical experimental and theoretical studies in this field. PMID:19719257

  15. Multi-User Interference Cancellation Scheme(s) for Muliple Carrier Frequency Offset Compensation in Uplink OFDMA

    DEFF Research Database (Denmark)

    Nguyen, Huan Cong; Carvalho, Elisabeth De; Prasad, Ramjee

    2006-01-01

    We consider the uplink of an Orthogonal Frequency Division Multiple Access (OFDMA)-based system, where each Mobile Station (MS) experiences a different Carrier Frequency Offset (CFO). Uncorrected CFO destroy the orthogonality among subcarriers, which could cause severe Inter-Carrier Interference ...

  16. Interplay between hopping and band transport in high-mobility disordered semiconductors at large carrier concentrations: The case of the amorphous oxide InGaZnO

    Science.gov (United States)

    Fishchuk, I. I.; Kadashchuk, A.; Bhoolokam, A.; de Jamblinne de Meux, A.; Pourtois, G.; Gavrilyuk, M. M.; Köhler, A.; Bässler, H.; Heremans, P.; Genoe, J.

    2016-05-01

    We suggest an analytic theory based on the effective medium approximation (EMA) which is able to describe charge-carrier transport in a disordered semiconductor with a significant degree of degeneration realized at high carrier concentrations, especially relevant in some thin-film transistors (TFTs), when the Fermi level is very close to the conduction-band edge. The EMA model is based on special averaging of the Fermi-Dirac carrier distributions using a suitably normalized cumulative density-of-state distribution that includes both delocalized states and the localized states. The principal advantage of the present model is its ability to describe universally effective drift and Hall mobility in heterogeneous materials as a function of disorder, temperature, and carrier concentration within the same theoretical formalism. It also bridges a gap between hopping and bandlike transport in an energetically heterogeneous system. The key assumption of the model is that the charge carriers move through delocalized states and that, in addition to the tail of the localized states, the disorder can give rise to spatial energy variation of the transport-band edge being described by a Gaussian distribution. It can explain a puzzling observation of activated and carrier-concentration-dependent Hall mobility in a disordered system featuring an ideal Hall effect. The present model has been successfully applied to describe experimental results on the charge transport measured in an amorphous oxide semiconductor, In-Ga-Zn-O (a-IGZO). In particular, the model reproduces well both the conventional Meyer-Neldel (MN) compensation behavior for the charge-carrier mobility and inverse-MN effect for the conductivity observed in the same a-IGZO TFT. The model was further supported by ab initio calculations revealing that the amorphization of IGZO gives rise to variation of the conduction-band edge rather than to the creation of localized states. The obtained changes agree with the one we

  17. Carrier concentration profiling in magnetic GaMnSb/GaSb investigated by electrochemistry capacitance-voltage profiler

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Depth profiles of carrier concentrations in Ga- MnSb/GaSb are investigated by electrochemistry capacitance-voltage profiler and electrolyte of Tiron. The carrier concentration in GaMnSb/GaSb measured by this method is coincident with the results of Hall and X-ray diffraction measurements. It is indicated that most of the Mn atoms in GaMnSb take the site of Ga, play a role of acceptors, and provide shallow acceptor level(s).

  18. Effects of Ge substitution in GeTe by Ag or Sb on the Seebeck coefficient and carrier concentration derived from 125Te NMR

    Science.gov (United States)

    Levin, E. M.

    2016-01-01

    GeTe, a self-doping p -type semiconductor where the high free hole concentration is determined by Ge vacancies is a well-known base for high-efficiency A gxS bxG e50 -2 xT e50 (a tellurium-antimony-germanium-silver series) thermoelectric materials. Here it is shown that the replacement of Ge by Ag in GeTe (a A gxG e50 -xT e50 system) significantly decreases the Seebeck coefficient, whereas the replacement by Sb (S bxG e50 -xT e50 ) increases it. These effects can be attributed to a change in carrier concentration and consistent with 125Te NMR spin-lattice relaxation measurements and NMR signal position, which is mostly dependent on the Knight shift. Opposite changes in carrier concentration in A gxG e50 -xT e50 and S bxG e50 -xT e50 can be explained by different valence electron configurations of Ag and Sb compared to that of Ge, which results in a different local electron imbalance and/or in a change in Ge vacancy formation energy and affects the total carrier concentration. Comparison of our data for GeTe, A g2G e48T e50 , and S b2G e48T e50 with those for A g2S b2G e46T e50 shows that the effects from Ag and Sb compensate for each other and supports the formation of [Ag +Sb ] atomic pairs suggested earlier based on theoretical calculations.

  19. Atomistic aspects of carrier concentration variation in post-annealed indium tin oxide films

    International Nuclear Information System (INIS)

    Post-annealing environment-dependent optical and electrical properties of indium tin oxide films grown on glass were examined. X-ray diffraction measurements revealed that all of the films exhibited poly-crystallinity after annealing at 400 °C for 10 min O2, in-air and N2. The optical property measurements yielded  >80% transmittances for all the films except for the as-grown and O2-annealed films, even though there were no significant optical band-gap energy differences. In the Hall measurements, all of the films exhibited n-type characteristics. However, the film annealed under the N2 environment showed the best electrical properties (highest carrier concentration and conductivity). The physical origin of electrical property variations due to annealing environment differences was explained by examining the core-level x-ray photoelectron spectra. (paper)

  20. Charge carrier effective mass and concentration derived from combination of Seebeck coefficient and 125Te NMR measurements in complex tellurides

    Science.gov (United States)

    Levin, E. M.

    2016-06-01

    Thermoelectric materials utilize the Seebeck effect to convert heat to electrical energy. The Seebeck coefficient (thermopower), S , depends on the free (mobile) carrier concentration, n , and effective mass, m*, as S ˜m*/n2 /3 . The carrier concentration in tellurides can be derived from 125Te nuclear magnetic resonance (NMR) spin-lattice relaxation measurements. The NMR spin-lattice relaxation rate, 1 /T1 , depends on both n and m* as 1 /T1˜(m*)3/2n (within classical Maxwell-Boltzmann statistics) or as 1 /T1˜(m*)2n2 /3 (within quantum Fermi-Dirac statistics), which challenges the correct determination of the carrier concentration in some materials by NMR. Here it is shown that the combination of the Seebeck coefficient and 125Te NMR spin-lattice relaxation measurements in complex tellurides provides a unique opportunity to derive the carrier effective mass and then to calculate the carrier concentration. This approach was used to study A gxS bxG e50-2xT e50 , well-known GeTe-based high-efficiency tellurium-antimony-germanium-silver thermoelectric materials, where the replacement of Ge by [Ag+Sb] results in significant enhancement of the Seebeck coefficient. Values of both m* and n derived using this combination show that the enhancement of thermopower can be attributed primarily to an increase of the carrier effective mass and partially to a decrease of the carrier concentration when the [Ag+Sb] content increases.

  1. Influence of tellurium content and chlorine concentration on carrier drift mobility of Se100-xTex:Cl glasses

    International Nuclear Information System (INIS)

    Carrier drift mobility in undoped and doped with chlorine Se100-xTex (0≤x≤10) glassy alloys has been investigated as a function of Te content and Cl concentration. It was found that the drift mobilities of both electrons and holes were decreased with Te content increasing. The dependence of the carriers drift mobilities on Cl concentration followed a complicated behavior and was resulted in rapid decrease of the hole mobility when chlorine concentration approached 0.1 at.%. The concentrations and energies of localized states controlling the charge transport in the material have been found depending on Te content and Cl concentration. The observed charge-transport features are considered to attribute to changes in the concentrations of intrinsic charged defects and explained in terms of VAP model. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Excitation dependent Raman studies of self-seeded grown InN nanoparticles with different carrier concentration.

    Science.gov (United States)

    Madapu, Kishore K; Polaki, S R; Dhara, Sandip

    2016-07-21

    High quality InN nanoparticles are grown using an atmospheric chemical vapour deposition technique via a self-seeded catalytic approach in the temperature range of 580-650 °C. In this temperature region, the nucleation barrier of InN is overcome by seeding low density In nanoparticles prior to introduction of reactive NH3. Samples with increasing carrier densities are grown, with the help of increasing growth temperature, to understand the role of carrier density in the optical phonon structure. Near-resonance Raman spectra show completely different phonon pictures compared to those for the off-resonance spectra. A Raman forbidden mode of B1(high), because of the possible breakdown of selection rules in the near-resonance conditions, is invoked for the first time. The intensity and frequency of this mode strongly depend on the carrier concentration in the sample. In off-resonance conditions, the A1(LO) mode for the sample with higher carrier concentration is dominated by Fano interference rather than plasmon-phonon coupling. Variation of the intensity of the B1(high) mode is correlated with a band filling effect, which is substantiated by the luminescence studies of the InN samples with different carrier concentrations. PMID:27345503

  3. Free-charge carrier parameters of n-type, p-type and compensated InN:Mg determined by Infrared Spectroscopic Ellipsometry

    CERN Document Server

    Schöche, S; Darakchieva, V; Wang, X; Yoshikawa, A; Wang, K; Araki, T; Nanishi, Y; Schubert, M

    2013-01-01

    Infrared spectroscopic ellipsometry is applied to investigate the free-charge carrier properties of Mg-doped InN films. Two representative sets of In-polar InN grown by molecular beam epitaxy with Mg concentrations ranging from $1.2\\times10^{17}$ cm$^{-3}$ to $8\\times10^{20}$ cm$^{-3}$ are compared. P-type conductivity is indicated for the Mg concentration range of $1\\times10^{18}$ cm$^{-3}$ to $9\\times10^{19}$ cm$^{-3}$ from a systematic investigation of the longitudinal optical phonon plasmon broadening and the mobility parameter in dependence of the Mg concentration. A parameterized model that accounts for the phonon-plasmon coupling is applied to determine the free-charge carrier concentration and mobility parameters in the doped bulk InN layer as well as the GaN template and undoped InN buffer layer for each sample. The free-charge carrier properties in the second sample set are consistent with the results determined in a comprehensive analysis of the first sample set reported earlier [Sch\\"oche et al., ...

  4. Charge carrier concentration dependence of encounter-limited bimolecular recombination in phase-separated organic semiconductor blends

    Science.gov (United States)

    Heiber, Michael C.; Nguyen, Thuc-Quyen; Deibel, Carsten

    2016-05-01

    Understanding how the complex intermolecular configurations and nanostructure present in organic semiconductor donor-acceptor blends impacts charge carrier motion, interactions, and recombination behavior is a critical fundamental issue with a particularly major impact on organic photovoltaic applications. In this study, kinetic Monte Carlo (KMC) simulations are used to numerically quantify the complex bimolecular charge carrier recombination behavior in idealized phase-separated blends. Recent KMC simulations have identified how the encounter-limited bimolecular recombination rate in these blends deviates from the often used Langevin model and have been used to construct the new power mean mobility model. Here, we make a challenging but crucial expansion to this work by determining the charge carrier concentration dependence of the encounter-limited bimolecular recombination coefficient. In doing so, we find that an accurate treatment of the long-range electrostatic interactions between charge carriers is critical, and we further argue that many previous KMC simulation studies have used a Coulomb cutoff radius that is too small, which causes a significant overestimation of the recombination rate. To shed more light on this issue, we determine the minimum cutoff radius required to reach an accuracy of less than ±10 % as a function of the domain size and the charge carrier concentration and then use this knowledge to accurately quantify the charge carrier concentration dependence of the recombination rate. Using these rigorous methods, we finally show that the parameters of the power mean mobility model are determined by a newly identified dimensionless ratio of the domain size to the average charge carrier separation distance.

  5. Improvement of Thermoelectric Properties of a-InGaZnO Thin Film by Optimizing Carrier Concentration

    Science.gov (United States)

    Fujimoto, Yuta; Uenuma, Mutsunori; Ishikawa, Yasuaki; Uraoka, Yukiharu

    2016-03-01

    We have investigated the thermoelectric properties of amorphous InGaZnO (a-IGZO) thin films optimized by adjusting the carrier concentration. The a-IGZO films were produced under various oxygen flow ratios [O2/(Ar + O2)] using radiofrequency magnetron sputtering. The Seebeck coefficient and electrical conductivity were measured from 100 K to 400 K. The measured Seebeck coefficient and electrical conductivity show a trade-off relation. The carrier concentration in the a-IGZO films increased with decreasing oxygen flow ratio. This result can be adequately explained by the increment of oxygen vacancies. We found that the power factor (PF) at 300 K had a maximum value of 82 × 10-6 W/m-K2, where the carrier density was 7.7 × 1019 cm-3. These results indicate that a-IGZO shows maximal PF in the transition region from nondegenerate to degenerate state.

  6. Analytical procedure for experimental quantification of carrier concentration in semiconductor devices by using electric scanning probe microscopy

    International Nuclear Information System (INIS)

    Scanning capacitance microscopy (SCM) is based on a contact-mode variant of atomic force microscopy, which is used for imaging two-dimensional carrier (electrons and holes) distributions in semiconductor devices. We introduced a method of quantification of the carrier concentration by experimentally deduced calibration curves, which were prepared for semiconductor materials such as silicon and silicon carbide. The analytical procedure was circulated to research organizations in a round-robin test. The effectiveness of the method was confirmed for practical analysis and for what is expected for industrial pre-standardization from the viewpoint of comparability among users. It was also applied to other electric scanning probe microscopy techniques such as scanning spreading resistance microscopy and scanning nonlinear dielectric microscopy. Their depth profiles of carrier concentration were found to be in good agreement with those characterized by SCM. These results suggest that our proposed method will be compatible with future next-generation microscopy. (paper)

  7. Free-charge carrier parameters of n-type, p-type and compensated InN:Mg determined by infrared spectroscopic ellipsometry

    OpenAIRE

    Schoehe, S.; Hofmann, T.; Darakchieva, Vanya; X Wang; Yoshikawa, A.; Wang, K.; Araki, T; Nanishi, Y; Schubert, M

    2014-01-01

    Infrared spectroscopic ellipsometry is applied to investigate the free-charge carrier properties of Mg-doped InN films. Two representative sets of In-polar InN grown by molecular beam epitaxy with Mg concentrations ranging from $1.2\\times10^{17}$ cm$^{-3}$ to $8\\times10^{20}$ cm$^{-3}$ are compared. P-type conductivity is indicated for the Mg concentration range of $1\\times10^{18}$ cm$^{-3}$ to $9\\times10^{19}$ cm$^{-3}$ from a systematic investigation of the longitudinal optical phonon plasm...

  8. Carrier concentration dependence of structural disorder in thermoelectric Sn1−xTe

    Directory of Open Access Journals (Sweden)

    Mattia Sist

    2016-09-01

    Full Text Available SnTe is a promising thermoelectric and topological insulator material. Here, the presumably simple rock salt crystal structure of SnTe is studied comprehensively by means of high-resolution synchrotron single-crystal and powder X-ray diffraction from 20 to 800 K. Two samples with different carrier concentrations (sample A = high, sample B = low have remarkably different atomic displacement parameters, especially at low temperatures. Both samples contain significant numbers of cation vacancies (1–2% and ordering of Sn vacancies possibly occurs on warming, as corroborated by the appearance of multiple phases and strain above 400 K. The possible presence of disorder and anharmonicity is investigated in view of the low thermal conductivity of SnTe. Refinement of anharmonic Gram–Charlier parameters reveals marginal anharmonicity for sample A, whereas sample B exhibits anharmonic effects even at low temperature. For both samples, no indications are found of a low-temperature rhombohedral phase. Maximum entropy method (MEM calculations are carried out, including nuclear-weighted X-ray MEM calculations (NXMEM. The atomic electron densities are spherical for sample A, whereas for sample B the Te electron density is elongated along the 〈100〉 direction, with the maximum being displaced from the lattice position at higher temperatures. Overall, the crystal structure of SnTe is found to be defective and sample-dependent, and therefore theoretical calculations of perfect rock salt structures are not expected to predict the properties of real materials.

  9. Carrier Density and Compensation in Semiconductors with Multi Dopants and Multi Transition Energy Levels: The Case of Cu Impurity in CdTe: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wei, S. H.; Ma, J.; Gessert, T. A.; Chin, K. K.

    2011-07-01

    Doping is one of the most important issues in semiconductor physics. The charge carrier generated by doping can profoundly change the properties of semiconductors and their performance in optoelectronic device applications, such as solar cells. Using detailed balance theory and first-principles calculated defect formation energies and transition energy levels, we derive general formulae to calculate carrier density for semiconductors with multi dopants and multi transition energy levels. As an example, we studied CdTe doped with Cu, in which VCd, CuCd, and Cui are the dominant defects/impurities. We show that in this system, when Cu concentration increases, the doping properties of the system can change from a poor p-type, to a poorer p-type, to a better p-type, and then to a poor p-type again, in good agreement with experimental observation of CdTe-based solar cells.

  10. Quantitative measurement of local carrier concentration of semiconductor from displacement current-voltage curve using a scanning vibrating tip

    Energy Technology Data Exchange (ETDEWEB)

    Majima, Yutaka; Oyama, Yutaka; Iwamoto, Mitsumasa

    2000-07-01

    A new scanning probe method for evaluating the local carrier concentration of semiconductors is presented. The distance between a semiconductor surface and a vibrating tip is changed sinusoidally, and is adjusted to as small as a few nm across which tunneling current I{sub T} flows between the semiconductor surface and the vibrating tip. Displacement current I{sub D} due to the change in electric flux from the semiconductor surface to the vibrating tip flows periodically in accordance with the vibration of the tip. I{sub T} also flows when the distance becomes minimum. Both I{sub T} and I{sub D} flow simultaneously when a d.c. tip voltage V is applied, and these two currents are separated by using a two-phase lock-in amplifier. I{sub D}-V curve is analyzed by taking into account two-dimensional electric flux profile under the tip. In the tip voltage range within which majority carriers are accumulated, I{sub D}-V curve is extrapolated by a straight line. On the contrary, the slope of the curve decreases as the tip voltage is reduced from the voltage range of the accumulation, indicating that the majority carriers are depleted at the center of the Si surface. The theoretical I{sub D}-V curves are in good agreement with the measurement in the tip voltage region where the majority carriers are both accumulated and depleted. The local carrier concentration is able to be determined by making the theoretical I{sub D}-V curve fit the experimental results without contacting the semiconductor surface.

  11. Thermoelectric properties of sintered type-II clathrates (K, Ba)24(Ga, Sn)136 with various carrier concentrations

    Science.gov (United States)

    Kishimoto, Kengo; Koda, Shota; Akai, Koji; Koyanagi, Tsuyoshi

    2015-09-01

    We reported the thermoelectric properties of the sintered type-II clathrate K8Ba16Ga40Sn96 in a previous paper [S. Koda et al., J. Appl. Phys. 116, 023710 (2014)]. The clathrate had a high dimensionless figure of merit ZT, namely, 0.93. In this study, we optimized the carrier concentration n by modifying the chemical compositions of (K, Ba)24(Ga, Sn)136 samples, and heat treated the sintered samples. The carrier mobilities μ were improved because of the reduction in potential barrier scattering at grain boundaries. The room-temperature (RT) n values varied from 7.7 × 1017 to 3.7 × 1019 cm-3; the maximum RT μ value was 170 cm2V-1s-1. Consequently, we obtained a high ZT value of 1.19 at 630 K for n = 2.5 × 1019 cm-3. This material therefore has good thermoelectric properties.

  12. Analysis of thermoelectric properties of amorphous InGaZnO thin film by controlling carrier concentration

    Directory of Open Access Journals (Sweden)

    Yuta Fujimoto

    2015-09-01

    Full Text Available We have investigated the thermoelectric properties of amorphous InGaZnO (a-IGZO thin films optimized by adjusting the carrier concentration. The a-IGZO films were produced under various oxygen flow ratios. The Seebeck coefficient and the electrical conductivity were measured from 100 to 400 K. We found that the power factor (PF at 300 K had a maximum value of 82 × 10−6 W/mK2, where the carrier density was 7.7 × 1019 cm−3. Moreover, the obtained data was analyzed by fitting the percolation model. Theoretical analysis revealed that the Fermi level was located approximately above the potential barrier when the PF became maximal. The thermoelectric properties were controlled by the relationship between the position of Fermi level and the height of potential energy barriers.

  13. Concentration Dependence of Luminescent Properties for Sr2TiO4:Eu3+ Red Phosphor and Its Charge Compensation

    Directory of Open Access Journals (Sweden)

    Zhou Lu

    2012-01-01

    Full Text Available Sr2TiO4:Eu3+ phosphors using M+ (M = Li+, Na+, and K+ as charge compensators were prepared by the solid-state reaction. The powders were investigated by powder X-ray diffraction (XRD and photoluminescence spectra (PL to study the phase composition, structure, and luminescent properties. The results showed that Li+ ion was the best charge compensator. The phase was Sr2TiO4 when the doping concentration was small (x≤10.0%. When x reached 15.0%, the phase turned into Sr3Ti3O7 because of the structure damage. The phosphor could be effectively excited by ultraviolet (365, 395 nm and blue light (465 nm, and thenitemitted intense red light that peaked at around 620 nm (5D0→7F2. In addition, the emission of 700 nm (5D0→7F4 enhanced the red light color purity. The CIE chromaticity coordinates of samples with the higher red emission were between (0.650, 0.344 and (0.635, 0.352. Doped layered titanate Sr2TiO4:Eu3+ is a promising candidate red phosphor for white LEDs which can be suited for both near-UV LED chip and blue LED chip.

  14. Carrier concentration-dependent electron transfer in Cu2O/ZnO nanorod arrays and their photocatalytic performance

    Science.gov (United States)

    Jiang, Tengfei; Xie, Tengfeng; Chen, Liping; Fu, Zewen; Wang, Dejun

    2013-03-01

    In this paper, we have engineered the interface electronic structure in Cu2O/ZnO nanorod arrays, via adjusting the carrier concentration of Cu2O, and applied them to photocatalysis. The photoinduced charge transfer kinetics at the interface between Cu2O and ZnO were systematically investigated. The Cu2O (pH 11.0)/ZnO nanorod arrays have the largest magnitude of interfacial electric field, and photoinduced charge carriers can be separated rapidly and efficiently, which generates the highest photocatalytic efficiency for the reduction of methylviologen. Heterojunction construction is an exciting direction to pursue for highly active photocatalysts, and also offers opportunities to investigate the relationship between the electronic structure and the photocatalytic performance.In this paper, we have engineered the interface electronic structure in Cu2O/ZnO nanorod arrays, via adjusting the carrier concentration of Cu2O, and applied them to photocatalysis. The photoinduced charge transfer kinetics at the interface between Cu2O and ZnO were systematically investigated. The Cu2O (pH 11.0)/ZnO nanorod arrays have the largest magnitude of interfacial electric field, and photoinduced charge carriers can be separated rapidly and efficiently, which generates the highest photocatalytic efficiency for the reduction of methylviologen. Heterojunction construction is an exciting direction to pursue for highly active photocatalysts, and also offers opportunities to investigate the relationship between the electronic structure and the photocatalytic performance. Electronic supplementary information (ESI) available: SEM images, XRD patterns, photocatalytic activities, Mott-Schottky plots, modulation frequency and light intensity dependent SPV measurements. See DOI: 10.1039/c3nr34219k

  15. Influence of solution concentration on orientation and related carrier mobility of P3HT thin film by synchrotron GIXRD

    International Nuclear Information System (INIS)

    Background: Molecule chain orientations of conjugated polymer have dramatic influence on corresponding device performance, which can be controlled by the methods such as varying the solvents with different boiling point. Purpose: We attempted to study the influence of solution concentration on orientation and related carrier mobility of P3HT thin film. Methods: The P3HT thin films were made by spin-coating from chloroform solution of different concentration and characterized using UV-Vis absorption spectra, grazing incidence X-ray diffraction. The organic thin film transistors were also fabricated to characterize the corresponding mobility . Results: The absorption peaks of the thin film prepared with low concentration solution red-shifted compared with that of high concentration. In out-of-plane GIXRD the relative intensity of (100) peak increased with decreasing concentration while the (010) peak moved in reverse. (100) diffraction dot in 2D GIXRD of thin film prepared with high concentration solution was mainly in out-of-plane direction while that with low concentration solution was mainly in in-plane direction. Conclusion: Based on the above results, the orientation changes from face-on orientation to edge-on orientation as the solution concentration decreases, which achieves the same effect with that of high boiling point solvents and enhances the mobility. It is possibly due to that low concentration solution needs more time to evaporate. (authors)

  16. Temperature Compensation in Determining of Remazol Black B Concentrations Using Plastic Optical Fiber Based Sensor

    Directory of Open Access Journals (Sweden)

    Su Sin Chong

    2014-08-01

    Full Text Available In this study, the construction and test of tapered plastic optical fiber (POF sensors, based on an intensity modulation approach are described. Tapered fiber sensors with different diameters of 0.65 mm, 0.45 mm, and 0.35 mm, were used to measure various concentrations of Remazol black B (RBB dye aqueous solutions at room temperature. The concentrations of the RBB solutions were varied from 0 ppm to 70 ppm. In addition, the effect of varying the temperature of the RBB solution was also investigated. In this case, the output of the sensor was measured at four different temperatures of 27 °C, 30 °C, 35 °C, and 40 °C, while its concentration was fixed at 50 ppm and 100 ppm. The experimental results show that the tapered POF with d = 0.45 mm achieves the best performance with a reasonably good sensitivity of 61 × 10−4 and a linearity of more than 99%. It also maintains a sufficient and stable signal when heat was applied to the solution with a linearity of more than 97%. Since the transmitted intensity is dependent on both the concentration and temperature of the analyte, multiple linear regression analysis was performed to combine the two independent variables into a single equation. The resulting equation was then validated experimentally and the best agreement between the calculated and experimental results was achieved by the sensor with d = 0.45 mm, where the minimum discrepancy is less than 5%. The authors conclude that POF-based sensors are suitable for RBB dye concentration sensing and, with refinement in fabrication, better results could be achieved. Their low fabrication cost, simple configuration, accuracy, and high sensitivity would attract many potential applications in chemical and biological sensing.

  17. Study on Dual-Concentric-Core Dispersion Compensating Photonic Crystal Fiber

    Directory of Open Access Journals (Sweden)

    Md. Selim Habib

    2012-08-01

    Full Text Available The dual-concentric-core photonic crystal fiber composed of pure silica and air is proposed in this paper. Around 1.55 μm, it exhibits a negative chromatic dispersion as high as –20000 ps/(km.nm. The finite element method with perfectly matched absorbing layers boundary condition is used to investigate the guiding properties. The explanations to propagation states of the fundamental mode and the second mode are given elaborately

  18. Determination of charge carrier concentration in doped nonpolar liquids by impedance spectroscopy in the presence of charge adsorption.

    Science.gov (United States)

    Yezer, Benjamin A; Khair, Aditya S; Sides, Paul J; Prieve, Dennis C

    2016-05-01

    The impedance of dodecane doped with sorbitan trioleate (Span 85), sorbitan monooleate (Span 80) and sorbitan monolaurate (Span 20) was measured as a function of frequency using a 10mV amplitude sinusoidal voltage applied across a parallel plate cell with a 10μm spacing. The tested solutions varied in concentration from 1mM to 100mM and the frequency range was 10(-2)-10(4)Hz. Nyquist plots of all three surfactants showed the high frequency semicircle characteristic of parallel resistance and capacitance but often exhibited a second semicircle at low frequencies which was attributed to charge adsorption and desorption. The electrical conductivity of each surfactant was proportional to surfactant concentration for concentrations above 10mM. Fitting the data to models for charge migration, differential capacitance, and adsorption allowed extraction of both charge concentration and two kinetic parameters that characterize the rate of adsorption and desorption. Above 10mM the ratio of charge carriers per surfactant molecule was 22ppm for Span 20, 3ppm for Span 80, and 0.2ppm for Span 85. A higher number of charge carriers per molecule of surfactant was associated with larger micelles. The adsorption rate constants were independent of surfactant concentration while the desorption rate constants were proportional to the surfactant concentration. This dependence indicated that uncharged surfactant, whether in micelles or not, participated in the desorption of charge. Predictions of the adsorption/desorption model for large constant electric fields agreed qualitatively with data from the literature (Karvar et al., 2014). PMID:26905337

  19. Variation of carrier concentration and interface trap density in 8MeV electron irradiated c-Si solar cells

    International Nuclear Information System (INIS)

    The capacitance and conductance measurements were carried out for c-Si solar cells, irradiated with 8 MeV electrons with doses ranging from 5kGy – 100kGy in order to investigate the anomalous degradation of the cells in the radiation harsh environments. Capacitance – Voltage measurements indicate that there is a slight reduction in the carrier concentration upon electron irradiation due to the creation of radiation induced defects. The conductance measurement results reveal that the interface state densities and the trap time constant increases with electron dose due to displacement damages in c-Si solar cells

  20. Optimization of the concentration's distribution of the carriers on thickness of epitaxial layers

    OpenAIRE

    Karimov A. V.; Yodgorova D. M.; Giyasova F. A.; Saidova R. A.; Haydarov Sh. A.

    2007-01-01

    A plunger device for liquid epitaxy of АIIIВV semiconductor compositions has been modified. It has been shown that the impurity concentration gradient, creating inner electrical fields in the photodetecting and active regions of semiconductor structures, can be controlled by selecting the mechanism of extruding solution melt.

  1. Optimization of the concentration's distribution of the carriers on thickness of epitaxial layers

    Directory of Open Access Journals (Sweden)

    Karimov A. V.

    2007-12-01

    Full Text Available A plunger device for liquid epitaxy of АIIIВV semiconductor compositions has been modified. It has been shown that the impurity concentration gradient, creating inner electrical fields in the photodetecting and active regions of semiconductor structures, can be controlled by selecting the mechanism of extruding solution melt.

  2. Dopant and carrier concentration in Si in equilibrium with monoclinic SiP precipitates

    Science.gov (United States)

    Solmi, S.; Parisini, A.; Angelucci, R.; Armigliato, A.; Nobili, D.; Moro, L.

    1996-03-01

    The behavior of silicon slices very heavily implanted (1.5×1017 cm-2) with phosphorus was investigated by transmission electron microscopy and secondary neutral mass spectrometry (SNMS) after annealing at 800, 850, 900, and 1000 °C. Precipitation of large monoclinic, and partially orthorhombic, SiP particles takes place in the most heavily doped region. From the shape of the SNMS profiles in the dissolution stage of these precipitates, we determined the concentration Csat of P in equilibrium with the conjugate phase: Csat=2.45×1023exp(-0.62/kT) cm-3. This concentration has to be compared with the equilibrium concentration ne of the electrically active dopant. To this end, more accurate determinations of ne were performed on heavily P-doped polysilicon films. It was found that ne=1.3×1022exp(-0.37/kT) cm-3. Hence for T>~750 °C, Csat exceeds ne and the concentration (Csat-ne) of inactive mobile P increases with temperature. The formation and the diffusion behavior of this inactive dopant are in keeping with a preprecipitation phenomenon.

  3. DFT Study on the Carrier Concentration and Temperature-Dependent Thermoelectric Properties of Antimony Selenide

    Directory of Open Access Journals (Sweden)

    Aditya Jayaraman

    2016-01-01

    Full Text Available We present the thermoelectric properties of Antimony Selenide (Sb2Se3 obtained using first principles calculations. We investigated the electronic band structure using the FP-LAPW method within the sphere of the density functional theory. Thermoelectric properties were calculated using BoltzTrap code using the constant relaxation time (τ approximation at three different temperatures 300 K, 600 K, and 800 K. Seebeck coefficient (S was found to decrease with increasing temperature, electrical conductivity (σ/τ was almost constant in the entire temperature range, and electronic thermal conductivity (κ/τ increased with increasing temperature. With increase in temperature S decreased from 1870 μV/K (at 300 K to 719 μV/K (at 800 K, electronic thermal conductivity increased from 1.56 × 1015 W/m K s (at 300 K to 3.92 × 1015 W/m K s (at 800 K, and electrical conductivity decreased from 22 × 1019/Ω m s (at 300 K to 20 × 1019/Ω m s (at 800 K. The thermoelectric properties were also calculated for different hole concentrations and the optimum concentration for a good thermoelectric performance over a large range of temperatures (from 300 K to 1000 K was found for hole concentration around 1019 cm−3.

  4. Dual-recognition detection of Staphylococcus aureus using vancomycin-functionalized magnetic beads as concentration carriers.

    Science.gov (United States)

    Yang, Shijia; Ouyang, Hui; Su, Xiaoxiao; Gao, Hongfei; Kong, Weijun; Wang, Mengyao; Shu, Qi; Fu, Zhifeng

    2016-04-15

    Vancomycin, which has a strong antibacterial effect to Gram-positive bacteria, was adopted as one molecular recognition agent for bacterial detection. Magnetic beads (MBs) were functionalized with this antibiotic to effectively concentrate Staphylococcus aureus (S. aureus). In addition, alkaline phosphatase (ALP)-tagged rabbit immunoglobulin G (ALP-IgG) was used as the second recognition agent to improve the specificity based on the binding between the Fc region of rabbit IgG and protein A in the cell wall of S. aureus. MBs-concentrated sandwich complex of vancomycin/S. aureus/ALP-IgG was formed with a one-step incubation protocol. Then ALP chemiluminescent reaction was triggered by injecting substrate solution to quantitate S. aureus. Based on the sandwich molecular recognition mechanism and MBs concentration, an ultrasensitive, specific and rapid method was developed for S. aureus detection. The linear range for S. aureus detection was 12-1.2 × 10(6)CFU mL(-1), with a very low detection limit of 3.3 CFU mL(-1). The whole detection process could be completed in 75 min. Other Gram-positive bacteria and Gram-negative bacteria, including Escherichia coli, Salmonella, Pseudomonas aeruginosa, Micrococcus luteus, Bacillus cereus and Bacillus subtilis, showed negligible interference to S. aureus detection. This method was successfully used to quantitate S. aureus in lake water, milk, human urine and human saliva with acceptable recoveries ranging from 70.0% to 116.7%. PMID:26606309

  5. Phase analysis and determination of local charge carrier concentration in eutectic Mg2Si–Si alloys

    International Nuclear Information System (INIS)

    Multiphase materials attract attention due to possible combination of various properties attributed to each phase. The phase diagram of Mg–Si system shows that solidification of a melt containing about 45 and 55 at.% of Mg and Si should result in formation of Mg2Si and Si. Two alloys, Mg45Si55 and Mg46Si54 + 0.5 wt.% Cu have been synthesized and studied using XRD, SEM, and 29Si NMR at 300 K, and the Seebeck effect, electrical resistivity, and thermal conductivity in the temperature range of 300–750 K have been measured. 29Si NMR detects two distinct signals, at −177 and −80 ppm, in both materials, which are assigned to Mg2Si and Si phases, respectively. Both phases are slightly nonstoichiometric and doped with Mg. Two phases also are found by XRD and electron microscopy. 29Si NMR spin-lattice relaxation measurements in Mg2Si and Si phases show at least two components, short and long, which can be attributed to different local carrier concentrations, high and low, respectively, reflecting a local electronic inhomogeneity in each phase. The carrier concentrations range between 0.6 × 1019 and 9 × 1019 cm−3. The Seebeck coefficient in both alloys is mostly determined by the Si phase, while the thermal conductivity is limited by the Mg2Si phase with a lower value than that of the Si phase. By utilizing all characterization tools, we show how various experimental methods can be used as complementary methods to better understand the individual and combined properties of multiphase alloys. - Highlights: • Two distinct phases, Mg2Si and Si, are found in Mg45Si55 and Mg46Si54 + 0.5 wt.% Cu alloys. • 29Si NMR spin-lattice relaxation measurements demonstrate two relaxation components in each phase. • XRD, electron microscopy, and NMR have been demonstrated as complementary methods to study multiphase alloys

  6. Dopant and carrier concentration in silicon, in equilibrium with SiP precipitates

    Energy Technology Data Exchange (ETDEWEB)

    Solmi, S.; Parisini, A.; Armigliato, A.; Angelucci, R. [CNR-Istituto LAMEL, Bologna (Italy)] [and others

    1995-08-01

    The methods recently reported to study the equilibria hi the Si-As system, were extended to the Si-P. On this line the behaviour of Silicon slices very heavily implanted with 1.5 x 10{sup 17} P{sup +}/cm{sup 2}, was followed by transmission electron microscopy (TEM) and secondary neutral mass spectrometry (SNMS) after annealing at 800, 850, 900 and 1000 C. Precipitation of large monoclinic, and partially orthorhombic, SiP takes place hi the most heavily doped region. From the shape of the SNMS profiles in the dissolution stage of these precipitates, we determined for the First time, the concentration C{sub e} of P hi equilibrium with the conjugate phase: C. = 2.45 x 10{sup 23} exp (- 0.62/ kT) cm{sup -3}, were kT is in eV.

  7. Drug composition matters: the influence of carrier concentration on the radiochemical purity, hydroxyapatite affinity and in-vivo bone accumulation of the therapeutic radiopharmaceutical 188Rhenium-HEDP

    International Nuclear Information System (INIS)

    Introduction: 188Rhenium-HEDP is an effective bone-targeting therapeutic radiopharmaceutical, for treatment of osteoblastic bone metastases. It is known that the presence of carrier (non-radioactive rhenium as ammonium perrhenate) in the reaction mixture during labeling is a prerequisite for adequate bone affinity, but little is known about the optimal carrier concentration. Methods: We investigated the influence of carrier concentration in the formulation on the radiochemical purity, in-vitro hydroxyapatite affinity and the in-vivo bone accumulation of 188Rhenium-HEDP in mice. Results: The carrier concentration influenced hydroxyapatite binding in-vitro as well as bone accumulation in-vivo. Variation in hydroxyapatite binding with various carrier concentrations seemed to be mainly driven by variation in radiochemical purity. The in-vivo bone accumulation appeared to be more complex: satisfactory radiochemical purity and hydroxyapatite affinity did not necessarily predict acceptable bio-distribution of 188Rhenium-HEDP. Conclusions: For development of new bisphosphonate-based radiopharmaceuticals for clinical use, human administration should not be performed without previous animal bio-distribution experiments. Furthermore, our clinical formulation of 188Rhenium-HEDP, containing 10 μmol carrier, showed excellent bone accumulation that was comparable to other bisphosphonate-based radiopharmaceuticals, with no apparent uptake in other organs. Advances in knowledge: Radiochemical purity and in-vitro hydroxyapatite binding are not necessarily predictive of bone accumulation of 188Rhenium-HEDP in-vivo. Implications for patient care: The formulation for 188Rhenium-HEDP as developed by us for clinical use exhibits excellent bone uptake and variation in carrier concentration during preparation of this radiopharmaceutical should be avoided

  8. Phase analysis and determination of local charge carrier concentration in eutectic Mg{sub 2}Si–Si alloys

    Energy Technology Data Exchange (ETDEWEB)

    Levin, E.M., E-mail: levin@iastate.edu [Division of Materials Sciences and Engineering, US DOE Ames Laboratory, Ames, IA 50011 (United States); Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Hanus, R. [Division of Materials Sciences and Engineering, US DOE Ames Laboratory, Ames, IA 50011 (United States); Cui, J. [Division of Materials Sciences and Engineering, US DOE Ames Laboratory, Ames, IA 50011 (United States); Department of Chemistry, Iowa State University, Ames, IA 50011 (United States); Xing, Q.; Riedemann, T. [Division of Materials Sciences and Engineering, US DOE Ames Laboratory, Ames, IA 50011 (United States); Lograsso, T.A. [Division of Materials Sciences and Engineering, US DOE Ames Laboratory, Ames, IA 50011 (United States); Department of Materials Science and Engineering, Iowa State University, Ames, IA 50011 (United States); Schmidt-Rohr, K. [Division of Materials Sciences and Engineering, US DOE Ames Laboratory, Ames, IA 50011 (United States); Department of Chemistry, Iowa State University, Ames, IA 50011 (United States)

    2015-05-05

    Multiphase materials attract attention due to possible combination of various properties attributed to each phase. The phase diagram of Mg–Si system shows that solidification of a melt containing about 45 and 55 at.% of Mg and Si should result in formation of Mg{sub 2}Si and Si. Two alloys, Mg{sub 45}Si{sub 55} and Mg{sub 46}Si{sub 54} + 0.5 wt.% Cu have been synthesized and studied using XRD, SEM, and {sup 29}Si NMR at 300 K, and the Seebeck effect, electrical resistivity, and thermal conductivity in the temperature range of 300–750 K have been measured. {sup 29}Si NMR detects two distinct signals, at −177 and −80 ppm, in both materials, which are assigned to Mg{sub 2}Si and Si phases, respectively. Both phases are slightly nonstoichiometric and doped with Mg. Two phases also are found by XRD and electron microscopy. {sup 29}Si NMR spin-lattice relaxation measurements in Mg{sub 2}Si and Si phases show at least two components, short and long, which can be attributed to different local carrier concentrations, high and low, respectively, reflecting a local electronic inhomogeneity in each phase. The carrier concentrations range between 0.6 × 10{sup 19} and 9 × 10{sup 19} cm{sup −3}. The Seebeck coefficient in both alloys is mostly determined by the Si phase, while the thermal conductivity is limited by the Mg{sub 2}Si phase with a lower value than that of the Si phase. By utilizing all characterization tools, we show how various experimental methods can be used as complementary methods to better understand the individual and combined properties of multiphase alloys. - Highlights: • Two distinct phases, Mg{sub 2}Si and Si, are found in Mg{sub 45}Si{sub 55} and Mg{sub 46}Si{sub 54} + 0.5 wt.% Cu alloys. • {sup 29}Si NMR spin-lattice relaxation measurements demonstrate two relaxation components in each phase. • XRD, electron microscopy, and NMR have been demonstrated as complementary methods to study multiphase alloys.

  9. Field-effect measurements of mobility and carrier concentration of Cu2S colloidal quantum dot thin films after ligand exchange

    International Nuclear Information System (INIS)

    Colloidal quantum dots (CQDs) of copper sulfide (Cu2S), an earth-abundant semiconductor, have a number of intriguing applications that require knowledge of their electrical properties. Depending on stoichiometry, mobility, and surface treatment, applications include photoabsorbers for solar cells, tunable plasmonics, and counter-electrodes for polysulfate electrolytes. However, there have not been any direct measurements of electrical properties in Cu2S CQD thin films. Here, we exchange as synthesized dodecanethiol ligands with short ethanedithiol or ethylenediamine ligands to form thin films of coupled Cu2S CQDs. The mobility and carrier concentration were found to vary by ligand treatment from 10−5 cm2/Vs and 1019 holes/cm3 for ethanedithiol ligands to 10−3 cm2/Vs and 1020 holes/cm3 for ethylenediamine. These results are consistent with the carrier concentrations inferred from sub-bandgap surface-plasmon-resonances measured by infrared spectroscopy. These results will be useful when designing Cu2S materials for future applications. - Highlights: • Colloidal Cu2S quantum dots were synthesized and characterized. • Ligand exchange was performed to alter the Cu2S nanocrystal properties. • Ligand exchange was studied using photoluminescence and infrared spectroscopy. • Field effect mobility and carrier concentration were directly measured. • Carrier concentration was compared to estimates from surface plasmon resonances

  10. Hole traps associated with high-concentration residual carriers in p-type GaAsN grown by chemical beam epitaxy

    Science.gov (United States)

    Elleuch, Omar; Wang, Li; Lee, Kan-Hua; Demizu, Koshiro; Ikeda, Kazuma; Kojima, Nobuaki; Ohshita, Yoshio; Yamaguchi, Masafumi

    2015-01-01

    The hole traps associated with high background doping in p-type GaAsN grown by chemical beam epitaxy are studied based on the changes of carrier concentration, junction capacitance, and hole traps properties due to the annealing. The carrier concentration was increased dramatically with annealing time, based on capacitance-voltage (C-V) measurement. In addition, the temperature dependence of the junction capacitance (C-T) was increased rapidly two times. Such behavior is explained by the thermal ionization of two acceptor states. These acceptors are the main cause of high background doping in the film, since the estimated carrier concentration from C-T results explains the measured carrier concentration at room temperature using C-V method. The acceptor states became shallower after annealing, and hence their structures are thermally unstable. Deep level transient spectroscopy (DLTS) showed that the HC2 hole trap was composed of two signals, labeled HC21 and HC22. These defects correspond to the acceptor levels, as their energy levels obtained from DLTS are similar to those deduced from C-T. The capture cross sections of HC21 and HC22 are larger than those of single acceptors. In addition, their energy levels and capture cross sections change in the same way due to the annealing. This tendency suggests that HC21 and HC22 signals originate from the same defect which acts as a double acceptor.

  11. Field-effect measurements of mobility and carrier concentration of Cu{sub 2}S colloidal quantum dot thin films after ligand exchange

    Energy Technology Data Exchange (ETDEWEB)

    Brewer, Adam S.; Arnold, Michael S., E-mail: msarnold@wisc.edu

    2014-09-30

    Colloidal quantum dots (CQDs) of copper sulfide (Cu{sub 2}S), an earth-abundant semiconductor, have a number of intriguing applications that require knowledge of their electrical properties. Depending on stoichiometry, mobility, and surface treatment, applications include photoabsorbers for solar cells, tunable plasmonics, and counter-electrodes for polysulfate electrolytes. However, there have not been any direct measurements of electrical properties in Cu{sub 2}S CQD thin films. Here, we exchange as synthesized dodecanethiol ligands with short ethanedithiol or ethylenediamine ligands to form thin films of coupled Cu{sub 2}S CQDs. The mobility and carrier concentration were found to vary by ligand treatment from 10{sup −5} cm{sup 2}/Vs and 10{sup 19} holes/cm{sup 3} for ethanedithiol ligands to 10{sup −3} cm{sup 2}/Vs and 10{sup 20} holes/cm{sup 3} for ethylenediamine. These results are consistent with the carrier concentrations inferred from sub-bandgap surface-plasmon-resonances measured by infrared spectroscopy. These results will be useful when designing Cu{sub 2}S materials for future applications. - Highlights: • Colloidal Cu2S quantum dots were synthesized and characterized. • Ligand exchange was performed to alter the Cu2S nanocrystal properties. • Ligand exchange was studied using photoluminescence and infrared spectroscopy. • Field effect mobility and carrier concentration were directly measured. • Carrier concentration was compared to estimates from surface plasmon resonances.

  12. Photoinduced Dedoping of Conducting Polymers: An Approach to Precise Control of the Carrier Concentration and Understanding Transport Properties.

    Science.gov (United States)

    Wei, Qingshuo; Mukaida, Masakazu; Kirihara, Kazuhiro; Naitoh, Yasuhisa; Ishida, Takao

    2016-01-27

    Exploring the various applications of conjugated polymers requires systematic studies of their physical properties as a function of the doping density, which, consequently, calls for precise control of their doping density. In this study, we report a novel solid-state photoinduced charge-transfer reaction that dedopes highly conductive polyelectrolyte complexes such as poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate). Varying the UV-irradiation time of this material allows the carrier density inside the film to be precisely controlled over more than 3 orders of magnitude. We extract the carrier density, carrier mobility, and Seebeck coefficient at different doping levels to obtain a clear image of carrier-transport mechanisms. This approach not only leads to a better understanding of the physical properties of the conducting polymer but also is useful for developing applications requiring patterned, large-area conducting polymers. PMID:26734776

  13. Simultaneous enhancement of carrier mobility and concentration via tailoring of Al-chemical states in Al-ZnO thin films

    International Nuclear Information System (INIS)

    Simultaneously achieving higher carriers concentration and mobility is a technical challenge against up-scaling the transparent-conductive performances of transparent-conductive oxides. Utilizing one order higher dense (∼1 × 1011 cm−3) plasmas (in comparison to the conventional direct current plasmas), highly c-axis oriented Al-doped ZnO films have been prepared with precise control over relative composition and chemical states of constituting elements. Tailoring of intrinsic (O vacancies) and extrinsic (ionic Al and zero-valent Al) dopants provide simultaneous enhancement in mobility and concentration of charge carriers. Room-temperature resistivity as low as 4.89 × 10−4 Ω cm along the carrier concentration 5.6 × 1020 cm−3 is obtained in 200 nm thick transparent films. Here, the control of atomic Al reduces the charge trapping at grain boundaries and subdues the effects of grain boundary scattering. A mechanism based on the correlation between electron-hole interaction and carrier mobility is proposed for degenerately doped wide band-gap semiconductors

  14. Structural modifications and non-monotonic carrier concentration in Bi2Se0.3Te2.7 by reversible electrochemical lithium reactions

    International Nuclear Information System (INIS)

    Reversible electrochemical lithium intercalation/deintercalation reactions have been applied to integrally modify the thermoelectric performance of Bi2Se0.3Te2.7 compounds. The carrier concentration of Bi2Se0.3Te2.7 has been precisely controlled experimentally through the adjustment of the residual lithium content. The variations of electronic transport properties of LixBi2Se0.3Te2.7, including electrical conductivity, Seebeck coefficient and carrier concentration, as a function of the intercalated lithium amount (x), show a special non-monotonic P-type to N-type doping trend. This variation is caused by the competition of two mechanisms controlling the carrier concentration: (i) decreasing of the Se/Te ratio through a Li–Se reaction that reduces the amount of the TeBi or SeBi antisite defects and therefore the electron concentration; (ii) n-type doping by lithium that provides the electron. Moreover, the nanoparticle exfoliation during lithium intercalation and deintercalation reactions leads to the formation of an internal nanocrystalline composite structure which effectively reduces the lattice thermal conductivity. Through an integral modification of both electrical and thermal transport properties, the maximum ZT value of LixBi2Se0.3Te2.7 was improved by nearly 25%

  15. Effects of low-temperature (120 °C) annealing on the carrier concentration and trap density in amorphous indium gallium zinc oxide thin film transistors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae-sung; Piao, Mingxing; Jang, Ho-Kyun; Kim, Gyu-Tae, E-mail: gtkim@korea.ac.kr [School of Electrical Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Oh, Byung Su [School of Electrical Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Samsung Display Company, Yongin (Korea, Republic of); Joo, Min-Kyu [School of Electrical Engineering, Korea University, Seoul 136-701 (Korea, Republic of); IMEP-LAHC, Grenoble INP, Minatec, CS 50257, 38016 Grenoble (France); Ahn, Seung-Eon [School of Electrical Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Samsung Advanced Institute of Technology, Samsung Electronics Corporations, Yongin 446-712 (Korea, Republic of)

    2014-12-28

    We report an investigation of the effects of low-temperature annealing on the electrical properties of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs). X-ray photoelectron spectroscopy was used to characterize the charge carrier concentration, which is related to the density of oxygen vacancies. The field-effect mobility was found to decrease as a function of the charge carrier concentration, owing to the presence of band-tail states. By employing the transmission line method, we show that the contact resistance did not significantly contribute to the changes in device performance after annealing. In addition, using low-frequency noise analyses, we found that the trap density decreased by a factor of 10 following annealing at 120 °C. The switching operation and on/off ratio of the a-IGZO TFTs improved considerably after low-temperature annealing.

  16. Arbitrary cross-section SEM-cathodoluminescence imaging of growth sectors and local carrier concentrations within micro-sampled semiconductor nanorods

    Science.gov (United States)

    Watanabe, Kentaro; Nagata, Takahiro; Oh, Seungjun; Wakayama, Yutaka; Sekiguchi, Takashi; Volk, János; Nakamura, Yoshiaki

    2016-02-01

    Future one-dimensional electronics require single-crystalline semiconductor free-standing nanorods grown with uniform electrical properties. However, this is currently unrealistic as each crystallographic plane of a nanorod grows at unique incorporation rates of environmental dopants, which forms axial and lateral growth sectors with different carrier concentrations. Here we propose a series of techniques that micro-sample a free-standing nanorod of interest, fabricate its arbitrary cross-sections by controlling focused ion beam incidence orientation, and visualize its internal carrier concentration map. ZnO nanorods are grown by selective area homoepitaxy in precursor aqueous solution, each of which has a (0001):+c top-plane and six {1-100}:m side-planes. Near-band-edge cathodoluminescence nanospectroscopy evaluates carrier concentration map within a nanorod at high spatial resolution (60 nm) and high sensitivity. It also visualizes +c and m growth sectors at arbitrary nanorod cross-section and history of local transient growth events within each growth sector. Our technique paves the way for well-defined bottom-up nanoelectronics.

  17. Current-voltage characteristic for bipolar p-n junction devices with drift fields, including correlation between carrier lifetimes and shallow-impurity concentration

    International Nuclear Information System (INIS)

    We present general analytic solutions for static current-voltage characteristics of quasineutral regions of nonilluminated semiconductor bipolar devices under the following assumptions: (a) the quasineutral region has a graded shallow-level impurity concentration producing a constant built-in electric (drift) field; (b) minority carriers injected into this region stay at concentrations low enough to avoid violation of low-injection conditions; (c) the minority-carrier lifetime of this region depends on position in accordance with a power-law dependence on the shallow-level donor concentration, a dependence that is consistent with the longest minority-carrier lifetimes measured and with the physical chemistry of divacancy-donor reactions at high temperatures. The solutions presented are apparently the first that include assumption (c). Modified Bessel functions of the first and second kind appear in these solutions. From a pheonomenological standpoint, the solutions may account for defect centers associated with vacancy complexes and, in part, for the gettering observed in highly doped n-type Si. Design implications for transistors, diodes, and solar cells are discussed quantitatively for a thin drift-field Si p/n(x) junction solar cell

  18. Arbitrary cross-section SEM-cathodoluminescence imaging of growth sectors and local carrier concentrations within micro-sampled semiconductor nanorods.

    Science.gov (United States)

    Watanabe, Kentaro; Nagata, Takahiro; Oh, Seungjun; Wakayama, Yutaka; Sekiguchi, Takashi; Volk, János; Nakamura, Yoshiaki

    2016-01-01

    Future one-dimensional electronics require single-crystalline semiconductor free-standing nanorods grown with uniform electrical properties. However, this is currently unrealistic as each crystallographic plane of a nanorod grows at unique incorporation rates of environmental dopants, which forms axial and lateral growth sectors with different carrier concentrations. Here we propose a series of techniques that micro-sample a free-standing nanorod of interest, fabricate its arbitrary cross-sections by controlling focused ion beam incidence orientation, and visualize its internal carrier concentration map. ZnO nanorods are grown by selective area homoepitaxy in precursor aqueous solution, each of which has a (0001):+c top-plane and six {1-100}:m side-planes. Near-band-edge cathodoluminescence nanospectroscopy evaluates carrier concentration map within a nanorod at high spatial resolution (60 nm) and high sensitivity. It also visualizes +c and m growth sectors at arbitrary nanorod cross-section and history of local transient growth events within each growth sector. Our technique paves the way for well-defined bottom-up nanoelectronics. PMID:26881966

  19. Perfect charge compensation in WTe2 for the extraordinary magnetoresistance: From bulk to monolayer

    OpenAIRE

    Lv, H. Y.; Lu, W. J.; Shao, D. F.; Liu, Y; Tan, S. G.; Y. P. Sun

    2014-01-01

    The electronic structure of WTe2 bulk and layers are investigated by using the first principles calculations. The perfect electron-hole (n-p) charge compensation and high carrier mobilities are found in WTe2 bulk, which may result in the large and non-saturating magnetoresistance (MR) observed very recently in the experiment [Ali et al., Nature 514, 205 (2014)]. The monolayer and bilayer of WTe2 preserve the semimetallic property, with the equal hole and electron carrier concentrations. Moreo...

  20. Serum concentration of sFas and sFasL in healthy HBsAg carriers, chronic viral hepatitis B and C patients

    Institute of Scientific and Technical Information of China (English)

    Tadeusz Wojciech Lapinski; Oksana Kowalczuk; Danuta Prokopowicz; Lech Chyczewski

    2004-01-01

    AIM: To estimate the amount of apoptosis among healthy HBsAg carriers, patients with chronic HBV infection treated with lamk udine and patients with chronic HCV infection treated with interferon alpha and ribavirin. Activity of apoptosis was evaluated by serum sFas/sFasL concentration measurement.Moreover dependence between apoptosis and HBV-DNA or HCV-RNA levels was studied.METHODS: Eighty-six persons were included into study: 34healthy HBsAg carriers, 33 patients with chronic HBV infection and 19 patients with chronic HCV infection. Serum levels of sFas/sFasL were measured by ELISA assay. HBV-DNA and HCV-RNA were measured by RT-PCR assay. Levels of sFas/sFasL were determined before and 2 and 12 wk after therapy in patients with chronic hepatitis B and C infection.HBV-DNA or HCV-RNA was detected before treatment and 6 mo after treatment.RESULTS: Twenty-four (71%) healthy HBsAg carriers showed HBV-DNA over 105/mL, which was comparable to the patients with chronic hepatitis B. Independently from HBV-DNA levels,the concentration of sFas among healthy HBsAg carriers was comparable to healthy persons. Among patients with chronic hepatitis B and C, the concentration of sFas was significantly higher in comparison to healthy HBsAg carriers and healthy persons. In chronic hepatitis B patients the concentration of sFas was decreased during lamivudine treatment. Among chronic hepatitis C patients the concentration of sFas was increased during IFN alpha and ribavirin treatment. sFasL was not detected in control group. Furthermore sFasL occurred more frequently in chronic hepatitis C patients in comparison to chronic hepatitis B patients.CONCLUSION: There are no correlations between apoptosis and HBV-DNA levels. However ther is an association between apoptosis and activity of inflammation in patients with chronic HBV infection. Apoptosis can be increased in patients with chronic hepatitis C by effective treatment which may be a result of apoptosis stimulation by IFN-α.

  1. Possible use of ignited sulphates as carrier for concentrating some radioactive species (e.g. 51Cr, 99Mo and 185W)

    International Nuclear Information System (INIS)

    A radioactive indicator study has been done to examine the feasibility of concentrating chromate, molybdate and tungstate species from extremely dilute solutions by using ignited lead sulphate and barium sulphate as carriers. The procedure consists of two steps; first, the radioactive tracer in dilute aqueous solution is carried under optimum conditions; secondly, the carried activity after washing can be leached back in minimal amount of water of specified acidity. An examination of working conditions e.g., (i) carrying as a function of pH2, amount of carrier and that of added inactive CrO24; (ii) adsorption/desorption efficiency as a function of lattice/non-lattice ion concn, and (iii) desorption as a function of pH of the eluant have been carried out in case of chromate species. Centrifuge method has been used. 3-4 extractions are needed for the maximum recovery of activity. (author)

  2. 42 CFR 415.60 - Allocation of physician compensation costs.

    Science.gov (United States)

    2010-10-01

    ... Physician Services § 415.60 Allocation of physician compensation costs. (a) Definition. For purposes of this... or the carrier. (2) Report the information on which the physician compensation allocation is based to the intermediary or the carrier on an annual basis and promptly notify the intermediary or carrier...

  3. Determination of the free carrier concentration in atomic-layer doped germanium thin films by infrared spectroscopy

    International Nuclear Information System (INIS)

    Novel silicon photonics applications requiring heavy n-type doping have recently driven a great deal of interest towards the phosphorous doping of germanium. In this work we report on infrared reflectance spectroscopy measurements of the electron density in heavily n-type doped germanium layers obtained by stacking multiple phosphorous δ-layers. Here, we demonstrate that the conventional Drude model of the electrodynamic response of free carriers in metals can be adapted to describe heavily doped semiconductor thin films. Consequently, the effect of the electron density on the plasma frequency, scattering rate and complex permittivity can be investigated. (special issue article)

  4. Tuning the carrier concentration using Zintl chemistry in Mg3Sb2, and its implications for thermoelectric figure-of-merit.

    Science.gov (United States)

    Bhardwaj, A; Chauhan, N S; Goel, S; Singh, Vijeta; Pulikkotil, J J; Senguttuvan, T D; Misra, D K

    2016-02-17

    Zintl compounds are potential candidates for efficient thermoelectric materials, because typically they are small band gap semiconductors. In addition, such compounds allow fine tuning of the carrier concentration by chemical doping for the optimization of thermoelectric performance. Herein, such tunability is demonstrated in Mg3Sb2-based Zintl compounds via Zn(2+) doping at the Mg(2+) site of the anionic framework (Mg2Sb2)(2-), in the series Mg3-xZnxSb2 (0 ≤ x ≤ 0.1). The materials have been successfully synthesized using the spark plasma sintering (SPS) technique. X-ray diffraction (XRD) analysis confirms a single solid solution phase of Mg3-xZnxSb2 (0 ≤ x ≤ 0.1). The thermoelectric properties are characterized by the Seebeck coefficient, electrical conductivity, and thermal conductivity measurements from 323 K to 773 K. Isoelectronic Zn substitution at the Mg site presents the controlled variation in the carrier concentration for optimizing the high power factor and reduced thermal conductivity. These results lead to a substantial increase in ZT of 0.37 at 773 K for a composition with x = 0.10 which is ∼42% higher than undoped Mg3Sb2. The electronic transport data for the Mg3-xZnxSb2 (0 ≤ x ≤ 0.1) compound are analyzed using a single parabolic band model predicting that Mg2.9Zn0.1Sb2 exhibits a near-optimal carrier concentration for high ZT. The electronic structure of transport properties of these disordered Mg3-xZnxSb2 (0 ≤ x ≤ 0.1) is also studied using density functional theory and the results obtained are in good agreement with experimental results. The low cost, lightness and non-toxicity of the constituent elements make these materials ideal for mid-temperature thermoelectric applications. PMID:26852729

  5. Ultra-low carrier concentration and surface-dominant transport in antimony-doped Bi2Se3 topological insulator nanoribbons

    KAUST Repository

    Hong, Seung Sae

    2012-03-27

    A topological insulator is the state of quantum matter possessing gapless spin-locking surface states across the bulk band gap, which has created new opportunities from novel electronics to energy conversion. However, the large concentration of bulk residual carriers has been a major challenge for revealing the property of the topological surface state by electron transport measurements. Here we report the surface-state-dominant transport in antimony-doped, zinc oxide-encapsulated Bi2Se3 nanoribbons with suppressed bulk electron concentration. In the nanoribbon with sub-10-nm thickness protected by a zinc oxide layer, we position the Fermi levels of the top and bottom surfaces near the Dirac point by electrostatic gating, achieving extremely low two-dimensional carrier concentration of 2×10 11cm-2. The zinc oxide-capped, antimony-doped Bi 2Se3 nanostructures provide an attractive materials platform to study fundamental physics in topological insulators, as well as future applications. © 2012 Macmillan Publishers Limited. All rights reserved.

  6. Carrier concentration dependence of donor activation energy in n-type GaN epilayers grown on Si (1 1 1) by plasma-assisted MBE

    International Nuclear Information System (INIS)

    Highlights: ► The n-type GaN layers were grown by plasma-assisted molecular beam epitaxy. ► The optical characteristics of a donor level in Si-doped GaN were studied. ► Activation energy of a Si-related donor was estimated from temperature dependent PL measurements. ► PL peak positions, FWHM of PL and activation energies are found to be proportional to the cube root of carrier density. ► The involvement of donor levels is supported by the temperature-dependent electron concentration measurements. -- Abstract: The n-type GaN layers were grown by plasma-assisted MBE and either intentionally doped with Si or unintentionally doped. The optical characteristics of a donor level in Si-doped, GaN were studied in terms of photoluminescence (PL) spectroscopy as a function of electron concentration. Temperature dependent PL measurements allowed us to estimate the activation energy of a Si-related donor from temperature-induced decay of PL intensity. PL peak positions, full width at half maximum of PL and activation energies are found to be proportional to the cube root of carrier density. The involvement of donor levels is supported by the temperature-dependent electron concentration measurements.

  7. Altered sodium intake affects plasma concentrations of BNP but not proBNP in healthy individuals and patients with compensated heart failure

    DEFF Research Database (Denmark)

    Damgaard, Morten; Goetze, Jens Peter; Norsk, Peter; Gadsbøll, Niels

    2007-01-01

    AIMS: Plasma B-type natriuretic peptide (BNP) and proBNP are promising markers for treatment of heart failure (HF), but the intra-individual biological variation is high. We investigated whether changes in sodium intake and posture contribute to this variation. METHODS AND RESULTS: A total of 12...... healthy individuals and 12 patients with medically treated compensated HF were examined after 1 week of low (70 mmol [1.61 g] per day) and 1 week of high (250 mmol [5.75 g] per day) sodium intake. Plasma volume and plasma concentrations of BNP and proBNP were determined after 1 h in seated and 1 h in...... supine position. In healthy individuals, the plasma BNP concentration increased significantly on high sodium intake with a ratio (high sodium/low sodium) of 2.00 (1.32-3.03, P = 0.004). The corresponding values for HF patients were 1.69 (1.25-2.29, P = 0.003). The plasma BNP concentration changed...

  8. Evolution of High-Temperature Superconductivity from a Low-T_{c} Phase Tuned by Carrier Concentration in FeSe Thin Flakes.

    Science.gov (United States)

    Lei, B; Cui, J H; Xiang, Z J; Shang, C; Wang, N Z; Ye, G J; Luo, X G; Wu, T; Sun, Z; Chen, X H

    2016-02-19

    We report the evolution of superconductivity in an FeSe thin flake with systematically regulated carrier concentrations by the liquid-gating technique. With electron doping tuned by the gate voltage, high-temperature superconductivity with an onset at 48 K can be achieved in an FeSe thin flake with T_{c} less than 10 K. This is the first time such high temperature superconductivity in FeSe is achieved without either an epitaxial interface or external pressure, and it definitely proves that the simple electron-doping process is able to induce high-temperature superconductivity with T_{c}^{onset} as high as 48 K in bulk FeSe. Intriguingly, our data also indicate that the superconductivity is suddenly changed from a low-T_{c} phase to a high-T_{c} phase with a Lifshitz transition at a certain carrier concentration. These results help to build a unified picture to understand the high-temperature superconductivity among all FeSe-derived superconductors and shed light on the further pursuit of a higher T_{c} in these materials. PMID:26943553

  9. Negative BOLD response and serotonin concentration within rostral subgenual portion of the anterior cingulate cortex for long-allele carriers during perceptual processing of emotional tasks

    Science.gov (United States)

    Hadi, Shamil M.; Siadat, Mohamad R.; Babajani-Feremi, Abbas

    2012-03-01

    We investigated the effect of synaptic serotonin concentration on hemodynamic responses. The stimuli paradigm involved the presentation of fearful and threatening facial expressions to a set of 24 subjects who were either5HTTLPR long- or short-allele carriers (12 of each type in each group). The BOLD signals of the rACC from subjects of each group were averaged to increase the signal-to-noise ratio. We used a Bayesian approach to estimate the parameters of the underlying hemodynamic model. Our results, during this perceptual processing of emotional task, showed a negative BOLD signal in the rACC in the subjects with long-alleles. In contrast, the subjects with short-alleles showed positive BOLD signals in the rACC. These results suggest that high synaptic serotonin concentration in the rACC inhibits neuronal activity in a fashion similar to GABA, and a consequent negative BOLD signal ensues.

  10. Effects of the multi-step activation process on the carrier concentration of p-type GaN

    International Nuclear Information System (INIS)

    Highlights: • Hole concentration of p-GaN was enhanced by multi-step activation process. • The O2 plasma treatment is attributed to the enhanced hole concentration of p-GaN. • PL peak intensity was also enhanced by MS activation process. - Abstract: A multi-step activation method, which include an oxygen plasma treatment, chemical treatment, and post annealing in N2 was proposed to enhance the hole concentration of a p-type GaN epitaxial layer. This process was found to effectively activate p-GaN by increasing the hole concentration compared to that of the conventionally annealed sample. After the optimal oxygen plasma treatment (10 min at a source and table power of 500 W and 100 W, respectively), followed by a HCl and buffered oxide etchant treatment, and then by a post-RTA process in a N2 environment, the hole concentration was increased from 4.0 × 1017 to 2.0 × 1018 cm−3. The oxygen plasma was found to effectively remove the remaining H atoms and subsequent wet treatment can effectively remove the GaOx that had formed during O plasma treatment, resulting in the higher intensity of photoluminescence

  11. Temperature Dependent Luminescent Decay Properties of CdTe Quantum Dot Monolayers: Impact of Concentration on Carrier Trapping

    CERN Document Server

    Murphy, Graham P; Bradley, A Louise

    2016-01-01

    We have investigated the temperature dependence of the photoluminescence spectra and average photoluminescence decay rate of CdTe quantum dot monolayers of different sizes as a function of concentration in the range 77 K to 296 K. It is shown that a simple three level analytic model involving bright and dark exciton states can only describe the lower temperature data but is unable to satisfactorily fit the data over the full temperature range. An extended model which includes external trap states is necessary to fit the data above approximately 150 K. Parameters for the model are obtained using both temporal and spectral data. The model indicates that the efficiency of interaction with trap states increases as the QD monolayer concentration increases, which is likely due to an increase in the density of available traps.

  12. An approach for manganese biomonitoring using a manganese carrier switch in serum from transferrin to citrate at slightly elevated manganese concentration.

    Science.gov (United States)

    Michalke, B; Aslanoglou, L; Ochsenkühn-Petropoulou, M; Bergström, B; Berthele, A; Vinceti, M; Lucio, M; Lidén, G

    2015-10-01

    After high-dose-short-term exposure (usually from occupational exposure) and even more under low-dose long term exposure (mainly environmental) manganese (Mn) biomonitoring is still problematic since these exposure scenarios are not necessarily reflected by a significant increase of total Mn in blood or serum. Usually, Mn concentrations of exposed and unexposed persons overlap and individual differentiation is often not possible. In this paper Mn speciation on a large sample size (n=180) was used in order to be able to differentiate between highly Mn-exposed or low or unexposed individuals at low total Mn concentration in serum (Mn(S)). The whole sample set consisted of three subsets from Munich, Emilia Romagna region in Italy and from Sweden. It turned out that also at low total Mn(S) concentrations a change in major Mn carriers in serum takes place from Mn-transferrin (Mn-Tf(S)) towards Mn-citrate (Mn-Cit(S)) with high statistical significance (poccupation, health status or other aspects. Based on our results, Mn-Cit(S) determination was considered as a potential means for estimating the Mn load in brain and CSF, i.e., it could be used as a biomarker for Mn beyond neural barrier. For a simpler Mn-Cit(S) determination than size exclusion chromatography inductively coupled plasma mass spectrometry (SEC-ICP-MS), ultrafiltration (UF) of serum samples was tested for suitability, the latter possibly being a preferred choice for routine occupational medicine laboratories. Our results revealed that UF could be an alternative if methodical prerequisites and limitations are carefully considered. These prerequisites were determined to be a thorough cleaning procedure at a minimum Mn(S) concentration >1.5μg/L, as at lower concentrations a wide scattering of the measured concentrations in comparison to the standardized SEC-ICP-MS results were observed. PMID:26302922

  13. Losses compensation; Compensation des pertes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    One mission of RTE (Electric Power Transportation), is to watch over the losses compensation resulting from the power transport on the electric power network. Since january 2001, RTE makes good the electric losses by the purchase of energy. To choose the marketers, a consultation has been realized by RTE. This document presents the rules concerning these losses compensation. (A.L.B.)

  14. 14 CFR 121.578 - Cabin ozone concentration.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Cabin ozone concentration. 121.578 Section...) AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.578 Cabin ozone...

  15. Energy Band Gap, Intrinsic Carrier Concentration and Fermi Level of CdTe Bulk Crystal between 304 K and 1067 K

    Science.gov (United States)

    Su, Ching-Hua

    2007-01-01

    Optical transmission measurements were performed on CdTe bulk single crystal. It was found that when a sliced and polished CdTe wafer was used, a white film started to develop when the sample was heated above 530 K and the sample became opaque. Therefore, a bulk crystal of CdTe was first grown in the window area by physical vapor transport; the optical transmission was then measured and from which the energy band gap was derived between 304 and 1067 K. The band gaps of CdTe can be fit well as a function of temperature using the Varshini expression: Eg (e V) = 1.5860 - 5.9117xl0(exp -4) T(sup 2)/(T + 160). Using the band gap data, the high temperature electron-hole equilibrium was calculated numerically by assuming the Kane's conduction band structure and a heavy-hole parabolic valance band. The calculated intrinsic carrier concentrations agree well with the experimental data reported previously. The calculated intrinsic Fermi levels between 270 and 1200 K were also presented.

  16. Questioning Compensation

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Transparent management and open information needed for the fund set up to compensate victims of the 2008 Sanlu milk scandal Almost three years after the Sanlu milk scandal that caused thousands of infants in China to develop urinary disease after drinking melamine

  17. Local composition and carrier concentration in Pb0.7Ge0.3Te and Pb0.5Ge0.5Te alloys from 125Te NMR and microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Levin, E M [Ames Laboratory; Kramer, M J [Ames Laboratory; Schmidt-Rohr, K [Ames Laboratory

    2014-11-01

    Pb0.7Ge0.3Te and Pb0.5Ge0.5Te alloys, (i) quenched from 923 K or (ii) quenched and annealed at 573 K for 2 h, have been studied by 125Te NMR, X-ray diffraction, electron and optical microscopy, as well as energy dispersive spectroscopy. Depending on the composition and thermal treatment history, 125Te NMR spectra exhibit different resonance frequencies and spin-lattice relaxation times, which can be assigned to different phases in the alloy. Quenched and annealed Pb0.7Ge0.3Te alloys can be considered as solid solutions but are shown by NMR to have components with various carrier concentrations. Quenched and annealed Pb0.5Ge0.5Te alloys contain GeTe- and PbTe-based phases with different compositions and charge carrier concentrations. Based on the analysis of non-exponential 125Te NMR spin-lattice relaxation, the fractions and carrier concentrations of the various phases have been estimated. Our data show that alloying of PbTe with Ge results in the formation of chemically and electronically inhomogeneous systems. 125Te NMR can be used as an efficient probe to detect the local composition in equilibrium as well as non-equilibrium states, and to determine the local carrier concentrations in complex multiphase tellurides.

  18. Radionuclide carriers

    International Nuclear Information System (INIS)

    A new carrier for radionuclide technetium 99m has been prepared for scintiscanning purposes. The new preparate consists of physiologically acceptable water-insoluble Tcsup(99m)-carrier containing from 0.2 to 0.8 weight percent of stannic ion as reductor, bound to an anionic starch derivative with about 1-20% of phosphate substituents. (EG)

  19. Aircraft Carriers

    DEFF Research Database (Denmark)

    Nødskov, Kim; Kværnø, Ole

    the majority of its foreign trade, as well as its oil imports, upon which the country is totally dependent. China therefore has good reasons for acquiring an aircraft carrier to enable it to protect its national interests. An aircraft carrier would also be a prominent symbol of China’s future status...... information is pieced together, then a picture is created of a Chinese aircraft carrier program, where Varyag will be made operational for training purposes. With this as the model, China will build a similar sized carrier themselves. If this project does become a reality, then it will take many years for...... Kuznetsov carrier. The SU-33 is, in its modernized version, technologically at the same level as western combat aircraft in both the offensive as well as the defensive roles. But Russia and China currently have an arms trade 6 dispute that is likely to prevent a deal, unless the dispute is resolved. As an...

  20. Aircraft Carriers

    DEFF Research Database (Denmark)

    Nødskov, Kim; Kværnø, Ole

    as a great power in Asia and will balance the carrier acquisitions of the United States, the United Kingdom, Russia and India. China’s current military strategy is predominantly defensive, its offensive elements being mainly focused on Taiwan. If China decides to acquire a large carrier with...... offensive capabilities, then the country will also acquire the capability to project military power into the region beyond Taiwan, which it does not possess today. In this way, China will have the military capability to permit a change of strategy from the mainly defensive, mainland, Taiwan-based strategy...... to a more assertive strategy, with potentially far-reaching consequences for the countries of the region. The Chinese have bought several retired carriers, which they have studied in great detail. The largest is the Russian-built carrier Varyag of the Kuznetsov class, which today is anchored in the...

  1. 基于二种载流子体系的HgCdTe材料的霍尔电压与载流子浓度关系%The Relations between Hall Voltage and Carrier Concentration of Two Kinds of Carrier Conduction System for HgCdTe

    Institute of Scientific and Technical Information of China (English)

    彭曼泽; 李东升; 李秋妍; 田立萍; 吴刚

    2013-01-01

      Formula and curve of hall voltage and carrier concentration p/n are derived from hall coefficient formula of two kinds of carrier conduction system . Relations between hall voltage and conduction type of the material for a series of p/n values are analysed. The range of the hole concentration are defined, which is adapted to hall coefficient formula of single carrier conduction system or two kinds of carrier conduction system.%  利用二种载流子体系的霍尔系数公式导出该体系下霍尔电压与二种载流子浓度 p/n 之间的公式及曲线。分析了不同 p/n 值时霍尔电压值与材料导电类型的关系,确定了适合采用一种载流子体系材料及二种载流子体系材料霍尔系数公式的空穴浓度范围。

  2. Perfect charge compensation in WTe2 for the extraordinary magnetoresistance: From bulk to monolayer

    Science.gov (United States)

    Lv, H. Y.; Lu, W. J.; Shao, D. F.; Liu, Y.; Tan, S. G.; Sun, Y. P.

    2015-05-01

    The electronic structures of the WTe2 bulk and layers are investigated by using the first-principles calculations. The perfect electron-hole (n\\text-p) charge compensation and high carrier mobilities are found in the WTe2 bulk, which may result in the large and non-saturating magnetoresistance (MR) observed very recently in the experiment (Ali M. N. et al, Nature, 514 (2014) 205). The monolayer and bilayer of WTe2 preserve the semimetallic property, with equal hole and electron carrier concentrations. Moreover, very high carrier mobilities are also found in WTe2 monolayer, indicating that the WTe2 monolayer would have the same extraordinary MR effect as the bulk, which could have promising applications in nanostructured magnetic devices.

  3. Quantum oscillations of the topological surface states in low carrier concentration crystals of Bi2-xSbxTe3-ySey

    Science.gov (United States)

    Pan, Y.; Nikitin, A. M.; Wu, D.; Huang, Y. K.; Puri, A.; Wiedmann, S.; Zeitler, U.; Frantzeskakis, E.; van Heumen, E.; Golden, M. S.; de Visser, A.

    2016-02-01

    We report a high-field magnetotransport study on selected low-carrier crystals of the topological insulator Bi2-xSbxTe3-ySey. Monochromatic Shubnikov-de Haas (SdH) oscillations are observed at 4.2 K and their two-dimensional nature is confirmed by tilting the magnetic field with respect to the sample surface. With the help of Lifshitz-Kosevich theory, important transport parameters of the surface states are obtained, including the carrier density, cyclotron mass and mobility. For (x , y) =(0.50 , 1.3) the Landau level plot is analyzed in terms of a model based on a topological surface state in the presence of a non-ideal linear dispersion relation and a Zeeman term with gs=70 or - 54. Input parameters were taken from the electronic dispersion relation measured directly by angle resolved photoemission spectroscopy on crystals from the same batch. The Hall resistivity of the same crystal (thickness of 40 μm) is analyzed in a two-band model, from which we conclude that the ratio of the surface conductance to the total conductance amounts to 32%.

  4. Extended frequency compensation of a diamagnetic loop

    International Nuclear Information System (INIS)

    A method of compensation for a diamagnetic loop that is magnetically coupled to a concentric stainless-steel vacuum vessel is presented. This compensation method accounts for imperfect magnetic coupling between the vessel eddy currents, the diamagnetic loop, and the plasma diamagnetic currents, and it also corrects for a finite loading resistance on the diamagnetic loop. A procedure for adjusting and calibrating the active-filter compensation circuit is presented. It can be applied to internal or external diamagnetic loops. (author)

  5. Extraction of niobium and tantalum isotopes using organophosphorus compounds -- Part II -- Extraction of 'carrier-free' concentrations from HCl/LiCl solutions

    OpenAIRE

    Gates, J. M.

    2010-01-01

    We have studied the extraction of niobium and tantalum from mixed hydrochloric acid/lithium chloride media by bis(2-ethylhexyl) hydrogen phosphate (HDEHP) and bis(2-ethylhexyl) hydrogen phosphite (BEHP) as a function of hydrogen ion (H+) concentration. The amount of niobium extracted by both HDEHP and BEHP decreased with increasing hydrogen ion concentration. Equilibrium with niobium occurred within 10 s at all hydrogen ion concentrations for both systems. For tantalum, the amount extracted i...

  6. Preconception Carrier Screening

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Preconception Carrier Screening Home For Patients Search FAQs Preconception Carrier Screening ... Screening FAQ179, August 2012 PDF Format Preconception Carrier Screening Pregnancy What is preconception carrier screening? What is ...

  7. Which compensation for whom ?

    OpenAIRE

    Pascal Gastineau; Emmanuelle Taugourdeau

    2012-01-01

    This paper examines a situation where a decision-maker determines the appropriate compensation that should be implemented for a given ecological damage. The compensation can be either or both in monetary and environmental units to meet three goals : i) no aggregate welfare loss, ii) minimization of the cost associated with the compensation, iii) minimal environmental compensation requirement. The findings suggest that - in some cases - providing both monetary and environmental compensation ca...

  8. Thermoelectric power and carrier concentration ofLa2-xSrxCuO4(0.03<x<0.17)single crystals

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Thermoelectric power (S) measurements have been systematically investigated in high-quality La2-x-Srx-CuO4 single crystals with different Sr concentrations (x =0.03, 0.05, 0.07, 0.1, 0.12). In this doping range studied, S remains positive, and with the increase of Sr concentration,room-temperature thermoelectric power S (290 K) decreases.An empirical formula which presents a relationship between hole concentration P and room-temperature thermoelectric power S (290 K) is reported in this note. Based on the theory of metallic diffusion model, the experimental results are discussed.

  9. Properties of the Schottky Barriers on compensated PbTe

    Science.gov (United States)

    Sizov, F. F.; Tetyorkin, V. V.; Troyan, Yu. G.; Chopick, V. Yu.

    1989-05-01

    C-V, I-V and photoelectric characteristics were investigated for some metals with different work functions, deposited onto compensated PbTe substrates with low carrier concentrations N, P ⩽ 10 16cm -3. The surfaces of the PbTe substrates were prepared by anode-mechanical polishing, that results in enriching of the surface by Te. It was shown that the heights of the potential barriers Ø B of the Schottky contacts prepared by oxidization in air anode-mechanically polished PbTe surfaces do not depend on the metal work function of Cu, Ag, Au and In. The highest values of resistance-area product were obtained for the Cu/ p-PbTe contacts (R 0A≅ 1 × 10 4Ωcm 2) and were slightly lower than the R 0A value limited by the thermoemission current.

  10. Influence of external chloride concentration on the kinetics of mobile charges in the cell membrane of Valonia utricularis: Evidence for the existence of a chloride carrier

    OpenAIRE

    Wang, Jianning; Wehner, Günter; Benz, Roland; Zimmermann, Ulrich

    1991-01-01

    Charge pulse relaxation studies were performed on cells of the giant marine alga Valonia utricularis. Two exponential voltage relaxations were recorded as found previously (Benz, R., and U. Zimmermann. 1983. Biophys. J. 43:13-26.). The parameters of the two exponential voltage decays were studied as a function of the chloride concentration in the artificial sea water. Replacement of external chloride by 2(N-morpholino)ethanesulfonate (Mes-) had a dramatic influence on the four relaxation para...

  11. Extraction of niobium and tantalum isotopes using organophosphorus compounds - Part I - Extraction of 'carrier-free' metal concentrations from HCl solutions

    OpenAIRE

    Gates, Jacklyn

    2010-01-01

    The extraction of niobium (Nb) and tantalum (Ta) from hydrochloric acid media by bis(2-ethylhexyl) hydrogen phosphate (HDEHP) and bis(2-ethylhexyl) hydrogen phosphite (BEHP) was studied. The goal of the experiments is to find a system that demonstrates selectivity between the members of group five of the Periodic Table and is also suitable for the study of dubnium (Db, Z = 105). Experiments were performed at the trace level (10-16 M Nb or Ta) using hydrochloric acid with concentrations rangin...

  12. Compensating for environmental damages

    OpenAIRE

    GASTINEAU, Pascal; TAUGOURDEAU, Emmanuelle

    2014-01-01

    This paper examines a situation in which a decision-maker determines the appropriate compensation that should be awarded for a given amount of ecological damage. The compensation can take the form of either or both monetary and environmental units to meet three goals: i) minimisation of the cost associated with the compensation, ii) no aggregate welfare loss, and iii) minimal environmental compensation requirement. The findings suggest that – in some cases – providing both monetar...

  13. Essays in Executive Compensation

    NARCIS (Netherlands)

    D. Zhang (Dan)

    2012-01-01

    textabstractThis dissertation focuses on how executive compensation is designed and its implications for corporate finance and government regulations. Chapter 2 analyzes several proposals to restrict CEO compensation and calibrates two models of executive compensation that describe how firms would r

  14. Electrochemical concentration of no-carrier-added [18F]fluoride from [18O]water in a disposable microfluidic cell for radiosynthesis of 18F-labeled radiopharmaceuticals

    International Nuclear Information System (INIS)

    The realization of the electrochemical method for microfluidic radiosynthesis is described for concentrating aqueous no-carrier-added [18F]fluoride into an aprotic solvent in a disposable microfluidic cell. Flowing aqueous [18F]fluoride was introduced into a disposable microfluidic cell (16 μL) under an electric potential (10 V), followed by anhydrous MeCN. The trapped [18F]fluoride was released in MeCN containing Kryptofix 222-KHCO3 (ca. 60 μL) under heat and a reversed potential (-2.5 V). An automated module provided the [18F]fluoride ready for subsequent microfluidic radiosynthesis in overall radiochemical yields of 60% within 6 min.

  15. Production of no-carrier-added 135La at an 18 MeV cyclotron and its purification for investigations at a concentration range down to 10-15 mol/L

    International Nuclear Information System (INIS)

    The production of non-commercially available 135La by proton irradiation of an isotopically enriched [135Ba]BaCO3 target at a cyclotron is described. The purification of the radionuclide was performed by a La-selective resin. 135La was separated in no-carrier-added (n.c.a) form in a nitric acid solution with a radiochemical yield of 83 ± 5% and a total activity per batch of 43 ± 3 MBq. The enriched [135Ba]Ba was recycled to the carbonate form with a recovery of 90 ± 3%. On the basis of a detection limit of 1 Bq/mL, solutions of n.c.a. 135La could be measured down to the 10-15 mol/L concentration range.

  16. Production of no-carrier-added {sup 135}La at an 18 MeV cyclotron and its purification for investigations at a concentration range down to 10{sup -15} mol/L

    Energy Technology Data Exchange (ETDEWEB)

    Mansel, Alexander; Franke, Karsten [Helmholtz-Zentrum Dresden-Rossendorf, Leipzig (Germany). Reactive Transport Div.

    2015-07-01

    The production of non-commercially available {sup 135}La by proton irradiation of an isotopically enriched [{sup 135}Ba]BaCO{sub 3} target at a cyclotron is described. The purification of the radionuclide was performed by a La-selective resin. {sup 135}La was separated in no-carrier-added (n.c.a) form in a nitric acid solution with a radiochemical yield of 83 ± 5% and a total activity per batch of 43 ± 3 MBq. The enriched [{sup 135}Ba]Ba was recycled to the carbonate form with a recovery of 90 ± 3%. On the basis of a detection limit of 1 Bq/mL, solutions of n.c.a. {sup 135}La could be measured down to the 10{sup -15} mol/L concentration range.

  17. What Is Carrier Screening?

    Science.gov (United States)

    ... you want to learn. Search form Search Carrier screening You are here Home Testing & Services Testing for ... help you make the decision. What Is Carrier Screening? Carrier screening checks if a person is a " ...

  18. Effect of irradiation with MeV protons and electrons on the conductivity compensation and photoluminescence of moderately doped p-4H-SiC (CVD)

    International Nuclear Information System (INIS)

    The compensation of moderately doped p-4H-SiC samples grown by the chemical vapor deposition (CVD) method under irradiation with 0.9-MeV electrons and 15-MeV protons is studied. The experimentally measured carrier removal rates are 1.2–1.6 cm–1 for electrons and 240–260 cm–1 for protons. The dependence of the concentration of uncompensated acceptors and donors, measured in the study, demonstrates a linear decrease with increasing irradiation dose to the point of complete compensation. This run of the dependence shows that compensation of the samples is due to the transition of carriers to deep centers formed by primary radiation-induced defects. It is demonstrated that, in contrast to n-SiC (CVD), primary defects in the carbon sublattice of moderately doped p-SiC (CVD) only cannot account for the compensation process. In p-SiC, either primary defects in the silicon sublattice, or defects in both sublattices are responsible for conductivity compensation. Also, photoluminescence spectra are examined in relation to the irradiation dose

  19. Effect of irradiation with MeV protons and electrons on the conductivity compensation and photoluminescence of moderately doped p-4H-SiC (CVD)

    Energy Technology Data Exchange (ETDEWEB)

    Kozlovski, V. V. [St. Petersburg State Polytechnical University (Russian Federation); Lebedev, A. A., E-mail: shura.lebe@mail.ioffe.ru; Bogdanova, E. V.; Seredova, N. V. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation)

    2015-09-15

    The compensation of moderately doped p-4H-SiC samples grown by the chemical vapor deposition (CVD) method under irradiation with 0.9-MeV electrons and 15-MeV protons is studied. The experimentally measured carrier removal rates are 1.2–1.6 cm{sup –1} for electrons and 240–260 cm{sup –1} for protons. The dependence of the concentration of uncompensated acceptors and donors, measured in the study, demonstrates a linear decrease with increasing irradiation dose to the point of complete compensation. This run of the dependence shows that compensation of the samples is due to the transition of carriers to deep centers formed by primary radiation-induced defects. It is demonstrated that, in contrast to n-SiC (CVD), primary defects in the carbon sublattice of moderately doped p-SiC (CVD) only cannot account for the compensation process. In p-SiC, either primary defects in the silicon sublattice, or defects in both sublattices are responsible for conductivity compensation. Also, photoluminescence spectra are examined in relation to the irradiation dose.

  20. Enhanced Thermoelectric Performance in Cu-Intercalated BiTeI by Compensation Weakening Induced Mobility Improvement.

    Science.gov (United States)

    Wu, Lihua; Yang, Jiong; Chi, Miaofang; Wang, Shanyu; Wei, Ping; Zhang, Wenqing; Chen, Lidong; Yang, Jihui

    2015-01-01

    The low weighted carrier mobility has long been considered to be the key challenge for improvement of thermoelectric (TE) performance in BiTeI. The Rashba-effect-induced two-dimensional density of states in this bulk semiconductor is beneficial for thermopower enhancement, which makes it a prospective compound for TE applications. In this report, we show that intercalation of minor Cu-dopants can substantially alter the equilibria of defect reactions, selectively mediate the donor-acceptor compensation, and tune the defect concentration in the carrier conductive network. Consequently, the potential fluctuations responsible for electron scattering are reduced and the carrier mobility in BiTeI can be enhanced by a factor of two to three between 10 K and 300 K. The carrier concentration can also be optimized by tuning the Te/I composition ratio, leading to higher thermopower in this Rashba system. Cu-intercalation in BiTeI gives rise to higher power factor, slightly lower lattice thermal conductivity, and consequently improved figure of merit. Compared with pristine BiTe0.98I1.02, the TE performance in Cu0.05BiTeI reveals a 150% and 20% enhancement at 300 and 520 K, respectively. These results demonstrate that defect equilibria mediated by selective doping in complex TE and energy materials could be an effective approach to carrier mobility and performance optimization. PMID:26394841

  1. Understanding carbon compensation

    International Nuclear Information System (INIS)

    Today, everyone can compensate its carbon emissions on the Internet in few mouse clicks. But what is the meaning of this compensation? What are the mechanisms of voluntary compensation in the framework of the Kyoto protocol? How to participate to this system and to what organisation a company or an individual can call in to reduce his carbon footprint? Carbon compensation is one of the numerous instruments invented to fight against global warming. When it is not possible to reduce our own emissions, we can compensate them by financing projects allowing to reduce the emissions of another company or collectivity. In this book, the authors answer the questions regarding the mechanisms, implementation and efficiency of carbon compensation. (J.S.)

  2. Compensation for nature conservation

    OpenAIRE

    I D Hodge

    1989-01-01

    The approach adopted towards environmental management in the rural context is different from that in the urban context in that the first is generally based on voluntary controls accompanied by compensation, whereas the second is based on involuntary controls without compensation. The arguments relating to the payment of compensation are examined with the use of management agreements on Sites of Special Scientific Interest taken as an example. Criteria for determining whether or not compensati...

  3. Which compensation for whom?

    OpenAIRE

    GASTINEAU, Pascal; TAUGOURDEAU, Emmanuelle

    2012-01-01

    Cet article détermine la compensation optimale qu'un décideur public doit imposer de mettre en place à un pollueur responsable d'un dommage environnemental. La compensation peut être soit monétaire, soit environnementale, soit une combinaison des deux. Elle doit permettre d'atteindre trois objectifs : i) pas de perte de bien-être agrégée, ii) une minimisation du coût associé à la compensation, iii) une compensation écologique minimale. Les résultats montrent que - dans certains cas - une comp...

  4. Effects of carrier-carrier scattering on population inversion in graphene under pulse photoexcitation

    Science.gov (United States)

    Satou, Akira; Ryzhii, Victor; Otsuji, Taiichi

    2015-01-01

    We study the carrier relaxation dynamics in intrinsic graphene after pulse photoexcitation and reveal effects of intraband carrier-carrier scattering on population inversion in the terahertz region, by conducting simulation based on the quasi-classical Boltzmann equation. It is demonstrated that by changing the dielectric constant of the surrounding materials the rate of carrier-carrier scattering can be controlled and the relaxation dynamics differs for cases with low and high dielectric constants. It is also found that the Pauli blocking of photogeneration in case of the pulse photoexcitation causes decrease in the photocarrier concentration and thus weakening of population inversion with higher dielectric constant.

  5. Concentrations of long-chain acyl-acyl carrier proteins during fatty acid synthesis by chloroplasts isolated from pea (Pisum sativum), safflower (Carthamus tinctoris), and amaranthus (Amaranthus lividus) leaves

    International Nuclear Information System (INIS)

    Fatty acid synthesis from [1-14C]acetate by chloroplasts isolated from peas and amaranthus was linear for at least 15 min, whereas incorporation of the tracer into long-chain acyl-acyl carrier protein (ACP) did not increase after 2-3 min. When reactions were transferred to the dark after 3-5 min, long-chain acyl-ACPs lost about 90% of their radioactivity and total fatty acids retained all of theirs. Half-lives of the long-chain acyl-ACPs were estimated to be 10-15 s. Concentrations of palmitoyl-, stearoyl-, and oleoyl-ACP as indicated by equilibrium labeling during steady-state fatty acid synthesis, ranged from 0.6-1.1, 0.2-0.7, and 0.4-1.6 microM, respectively, for peas and from 1.6-1.9, 1.3-2.6, and 0.6-1.4 microM, respectively, for amaranthus. These values are based on a chloroplast volume of 47 microliters/mg chlorophyll and varied according to the mode of the incubation. A slow increase in activity of the fatty acid synthetase in safflower chloroplasts resulted in long-chain acyl-ACPs continuing to incorporate labeled acetate for 10 min. Upon re-illumination following a dark break, however, both fatty acid synthetase activity and acyl-ACP concentrations increased very rapidly. Palmitoyl-ACP was present at concentrations up to 2.5 microM in safflower chloroplasts, whereas those of stearoyl- and oleoyl-ACPs were in the lower ranges measured for peas. Acyl-ACPs were routinely separated from extracts of chloroplasts that had been synthesising long-chain fatty acids from labeled acetate by a minor modification of the method of Mancha et al. The results compared favorably with those obtained using alternative analytical methods such as adsorption to filter paper and partition chromatography on silicic acid columns

  6. Medical leadership compensation framework

    OpenAIRE

    Uhlíř, Tomáš

    2009-01-01

    This master thesis deals with outlining the rationale of redesigning medical leadership compensation framework within Interior Health Authority (IH). In particular, reviews IH's organizational structure, analyses job descriptions for medical leaders, recommends improvements of communication flow across the authority and designs medical leader's compensation model.

  7. Turbulence compensation: an overview

    Science.gov (United States)

    van Eekeren, Adam W. M.; Schutte, Klamer; Dijk, Judith; Schwering, Piet B. W.; van Iersel, Miranda; Doelman, Niek J.

    2012-06-01

    In general, long range visual detection, recognition and identification are hampered by turbulence caused by atmospheric conditions. Much research has been devoted to the field of turbulence compensation. One of the main advantages of turbulence compensation is that it enables visual identification over larger distances. In many (military) scenarios this is of crucial importance. In this paper we give an overview of several software and hardware approaches to compensate for the visual artifacts caused by turbulence. These approaches are very diverse and range from the use of dedicated hardware, such as adaptive optics, to the use of software methods, such as deconvolution and lucky imaging. For each approach the pros and cons are given and it is indicated for which scenario this approach is useful. In more detail we describe the turbulence compensation methods TNO has developed in the last years and place them in the context of the different turbulence compensation approaches and TNO's turbulence compensation roadmap. Furthermore we look forward and indicate the upcoming challenges in the field of turbulence compensation.

  8. Improved load-cell compensation

    Science.gov (United States)

    Egger, R. L.

    1977-01-01

    Improved bridge-compensation circuit saves considerable time in balancing bridge and wiring it for temperature compensation. Large bridge-balance compensation is made before temperature cycling and small adjustments are made with different type of wire.

  9. HOT CARRIER SENSITIVITY OF MOSFET's EXPOSED TO SYNCHROTRON-LIGHT

    OpenAIRE

    Przyrembel, G.; Mahnkopf, R.; Wagemann, H.

    1988-01-01

    The influence of synchrotron-light irradiation for p- and n-channel MOSFET's on their sensitivity to hot carrier degradation was investigated. The radiation induces additional interface states and a positive oxide charge. Annealing at 450°C reduces the interface state density to its initial value but not the oxide charge. A hot carrier stress can compensate this remaining charge by trapping electrons. This effect produces an enhanced shift of the threshold voltage compared to non-irradiated d...

  10. Self-regulation of charged defect compensation and formation energy pinning in semiconductors.

    Science.gov (United States)

    Yang, Ji-Hui; Yin, Wan-Jian; Park, Ji-Sang; Wei, Su-Huai

    2015-01-01

    Current theoretical analyses of defect properties without solving the detailed balance equations often estimate Fermi-level pinning position by omitting free carriers and assume defect concentrations can be always tuned by atomic chemical potentials. This could be misleading in some circumstance. Here we clarify that: (1) Because the Fermi-level pinning is determined not only by defect states but also by free carriers from band-edge states, band-edge states should be treated explicitly in the same footing as the defect states in practice; (2) defect formation energy, thus defect density, could be pinned and independent on atomic chemical potentials due to the entanglement of atomic chemical potentials and Fermi energy, in contrast to the usual expectation that defect formation energy can always be tuned by varying the atomic chemical potentials; and (3) the charged defect compensation behavior, i.e., most of donors are compensated by acceptors or vice versa, is self-regulated when defect formation energies are pinned. The last two phenomena are more dominant in wide-gap semiconductors or when the defect formation energies are small. Using NaCl and CH3NH3PbI3 as examples, we illustrate these unexpected behaviors. Our analysis thus provides new insights that enrich the understanding of the defect physics in semiconductors and insulators. PMID:26584670

  11. Adaptive beamforming and phase bias compensation for GNSS receiver

    Institute of Scientific and Technical Information of China (English)

    Hongwei Zhao; Baowang Lian; Juan Feng

    2015-01-01

    Adaptive antenna arrays have been used to mitigate the interference on global navigation satel ite system (GNSS) re-ceivers. The performance of interference mitigation depends on the beamforming algorithms adopted by the antenna array. However, the adaptive beamforming wil change the array pattern in real-time, which has the potential to introduce phase center biases into the antenna array. For precise applications, these phase biases must be mitigated or compensated because they wil bring errors in code phase and carrier phase measurements. A novel adaptive beamforming algorithm is proposed firstly, then the phase bias induced by the proposed algorithm is estimated, and final y a com-pensation strategy is addressed. Simulations demonstrate that the proposed beamforming algorithm suppresses effectively the strong interference and improves significantly the capturing performance of GNSS signals. Simultaneously, the bias compensation method avoids the loss of the carrier phase lock and reduces the phase measurement errors for GNSS receivers.

  12. Climate change and compensation

    DEFF Research Database (Denmark)

    Jensen, Karsten Klint; Flanagan, Tine Bech

    2013-01-01

    This paper presents a case for compensation of actual harm from climate change in the poorest countries. First, it is shown that climate change threatens to reverse the fight to eradicate poverty. Secondly, it is shown how the problems raised in the literature for compensation to some extent...... are based on misconceptions and do not apply to compensation of present actual harm. Finally, two arguments are presented to the effect that, in so far as developed countries accept a major commitment to mitigate climate change, they should also accept a commitment to address or compensate actual harm from...... climate change. The first argument appeals to the principle that if it is an injustice to cause risk of incurring harm in the future, then it is also an injustice to cause a similar harm now. The second argument appeals to the principle that if there is moral reason to reduce the risk of specific harms...

  13. Essays in Executive Compensation

    OpenAIRE

    Zhang, Dan

    2013-01-01

    This doctoral thesis is made of three empirical research papers focused on executive compensation topics. The first chapter is a solo paper, while the second and third papers are co-authored with Antonio Parbonetti. The first chapter answers to Bushman and Smith’s (2001) call for research on compensation of executives other than CEOs. Specifically, using a sample of 586 firm-year observations over the period 2000-2009, I investigate the economic determinants and effects on shareholder va...

  14. Optimal Sales Force Compensation

    OpenAIRE

    Matthias Kräkel; Anja Schöttner

    2014-01-01

    We analyze a dynamic moral-hazard model to derive optimal sales force compensation plans without imposing any ad hoc restrictions on the class of feasible incentive contracts. We explain when the compensation plans that are most common in practice - fixed salaries, quota-based bonuses, commissions, or a combination thereof - are optimal. Fixed salaries are optimal for small revenue-cost ratios. Quota-based bonuses (commissions) should be used if the revenue-cost ratio takes intermediate (larg...

  15. Carrier Statistics and Quantum Capacitance Models of Graphene Nanoscroll

    Directory of Open Access Journals (Sweden)

    M. Khaledian

    2014-01-01

    schematic perfect scroll-like Archimedes spiral. The DOS model was derived at first, while it was later applied to compute the carrier concentration and quantum capacitance model. Furthermore, the carrier concentration and quantum capacitance were modeled for both degenerate and nondegenerate regimes, along with examining the effect of structural parameters and chirality number on the density of state and carrier concentration. Latterly, the temperature effect on the quantum capacitance was studied too.

  16. Carrier-induced ferromagnetism in bulk phosphorus-doped Zn1-xMnxTe achieved by annealing under high pressure

    International Nuclear Information System (INIS)

    We report the observation of carrier-induced ferromagnetism in bulk phosphorus-doped Zn1-xMnxTe. Using high-pressure Bridgman growth and with post-growth high-pressure annealing, we were able to overcome self-compensation in this material, thus achieving unprecedented concentrations of electrically active acceptors. Magnetic susceptibility and magnetic circular dichroism measurements on samples prepared in this way clearly reveal ferromagnetic ordering of the Mn ions. For example, Zn0.97Mn0.03Te:P with hole concentration of p = 4.8 x 1018 cm-3 showed a Curie temperature TC 2.5 K. (authors)

  17. Enhanced job performance: a new role for military compensation

    OpenAIRE

    Frampton, James Scott.

    2000-01-01

    This study concentrates on aspects of military and civilian compensation that motivate employees and provide incentives upon which job performance and productivity may depend. The study achieves its end by applying successful attributes of civilian compensation to military remuneration systems. Its main purpose is to judge whether military pay is structured toward a modern view of performance-based compensation and whether it is comparable to civilian pay. At issue is a military pay system th...

  18. Compensation committee composition and CEO compensation – Finnish evidence

    OpenAIRE

    Uusitalo, Mikael

    2012-01-01

    PURPOSE OF THE STUDY The purpose of this study is to examine the effect of compensation committee composition on the level of CEO compensation. The composition of the compensation committee is analyzed by using five variables which are: 1) the proportion of non-independent directors, 2) the proportion of long-serving directors, 3) the proportion of CEO-directors, 4) the proportion of busy directors and 5) the presence of a blockholder on the compensation committee. CEO compensation is measure...

  19. Functional compensation of motor function in pre-symptomatic Huntington's disease

    DEFF Research Database (Denmark)

    Klöppel, Stefan; Draganski, Bogdan; Siebner, Hartwig R;

    2009-01-01

    Involuntary choreiform movements are a clinical hallmark of Huntington's disease. Studies in clinically affected patients suggest a shift of motor activations to parietal cortices in response to progressive neurodegeneration. Here, we studied pre-symptomatic gene carriers to examine the compensat...... pattern of motor compensation is flexible depending on the actual task demands on motor control....... identified a complex pattern of motor compensation in pre-symptomatic gene carriers. The results show that preclinical compensation goes beyond a simple shift of activity from premotor to parietal regions involving multiple compensatory mechanisms in executive and cognitive motor areas. Critically, the...

  20. Stealth Compensation Via Retirement Benefits

    OpenAIRE

    Lucian Arye Bebchuk; Fried, Jesse M.

    2004-01-01

    This paper analyzes an important form of "stealth compensation" provided to managers of public companies. We show how boards have been able to camouflage large amount of executive compensation through the use of retirement benefits and payments. Our study highlights the significant role that camouflage and stealth compensation play in the design of compensation arrangements. Our study also highlights the significance of whether information about compensation arrangements is not merely publicl...

  1. 海藻酸盐与异种骨构建组织工程载体的适宜浓度%Suitable concentration of alginate with xenograft for constructing bone tissue engineering carrier

    Institute of Scientific and Technical Information of China (English)

    孙磊; 孟国林; 窦榆生; 徐建强; 刘丹平; 胡蕴玉

    2007-01-01

    背景:研究认为,载体的结构在很大程度上影响着载体的功能.目的:探讨不同浓度的海藻酸盐凝胶与去抗原异种骨构建组织工程载体的生物学性能.设计:观察性实验.单位:解放军第四军医大学西京医院全军创伤骨科研究所.材料:海藻酸盐,氯化钙,骨髓基质细胞,异种骨.方法:取小牛松质骨,制成骨粒,脱脂、脱蛋白,真空冻干;选择孔隙直径在300~500 μm左右的骨粒,环氧乙烷消毒.将提纯后的海藻酸钠以DMEM培养液为溶剂,配制成0.5%,2%,8%和16%的海藻酸钠DMEM溶液;将诱导后的骨髓基质细胞以1×1012L-1浓度等体积与海藻酸钠DMEM溶液充分混合,在0.5 MPa的负压状态下复合,使细胞悬液充分占据松质骨的空隙,以50 g/L的葡萄酸钙浸渍30 s,以使海藻酸钠获得交联.置于CO2培养箱中,培养4 d.观察异种骨孔隙中凝胶复合情况及其中细胞生长情况.观察不同藻酸密度复合松质骨粒中细胞生长情况.主要观察指标:观察海藻酸盐凝胶与去抗原异种骨复合情况,复合后的载体中细胞生长状态和基质分泌情况.结果:海藻酸盐的浓度为0.25%,1%时,凝胶在异种骨中均匀复合,浓度为4%和8%时藻酸仅复合在松质骨表面.体外培养4 d后,0.25%海藻酸盐复合异种骨的表面大部分凝胶脱落,1%的海藻酸盐均匀复合在异种骨的骨孔中,细胞形态饱满,基质分泌;4%的海藻酸盐中,细胞生长受到限制;8%的凝胶的质地不均匀,无法见到细胞结构.结论:1%的海藻酸盐适宜与异种骨复合构建骨组织工程载体.%BACKGROUND:The structure of tissue engineering carrier affects the bio-action of cells greatly.OBJECTIVE: To investigate the biological characteristics of bone marrow stem cells (MSCs) in different concentrations of alginate combined with de-antigen bone xenograft (DBX).DESIGN: Observational trial.SETTING: PLA Institute of Trauma and Orthopedics, the Fourth Military Medical

  2. Hot carrier solar cell absorbers: investigation of carrier cooling properties of candidate materials

    Science.gov (United States)

    Conibeer, G.; Shrestha, Santosh; Huang, Shujuan; Patterson, Robert; Xia, Hongze; Feng, Yu; Zhang, Pengfei; Gupta, Neeti; Smyth, Suntrana; Liao, Yuanxun; Lin, Shu; Wang, Pei; Dai, Xi; Chung, Simon; Yang, Jianfeng; Zhang, Yi

    2015-09-01

    The hot carrier cell aims to extract the electrical energy from photo-generated carriers before they thermalize to the band edges. Hence it can potentially achieve a high current and a high voltage and hence very high efficiencies up to 65% under 1 sun and 86% under maximum concentration. To slow the rate of carrier thermalisation is very challenging, but modification of the phonon energies and the use of nanostructures are both promising ways to achieve some of the required slowing of carrier cooling. A number of materials and structures are being investigated with these properties and test structures are being fabricated. Initial measurements indicate slowed carrier cooling in III-Vs with large phonon band gaps and in multiple quantum wells. It is expected that soon proof of concept of hot carrier devices will pave the way for their development to fully functioning high efficiency solar cells.

  3. Compensation for nuclear damage

    International Nuclear Information System (INIS)

    To secure fair and efficient compensation for damage likely to be caused by the utilisation of nuclear energy, a special civil liability regime was set up by several international conventions. Three of these conventions are in force and Spain is a Contracting Party to all three. The principles established in the first instance at European level by the Paris Convention (absolute and exclusive liability of the nuclear operator, limitation of such liability, compulsory insurance...) are intended to guarantee that possible victims of a nuclear incident will obtain compensation for damage suffered. The Brussels Convention Supplementary to the Paris Convention provides for official funds to compensate victims through intervention by the Contracting Parties. Each Contracting Party should implement these Conventions at national level by appropriate legislation, which is what Spain did with its Act on Nuclear Energy of 29th April 1964, as supplemented in 1967 by the Regulations on Cover for Nuclear Hazards. (N.E.A.)

  4. Charge carrier coherence and Hall effect in organic semiconductors.

    Science.gov (United States)

    Yi, H T; Gartstein, Y N; Podzorov, V

    2016-01-01

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor. PMID:27025354

  5. Charge carrier coherence and Hall effect in organic semiconductors

    Science.gov (United States)

    Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

    2016-03-01

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.

  6. Parallelized unscented Kalman filters for carrier recovery in coherent optical communication.

    Science.gov (United States)

    Jignesh, Jokhakar; Corcoran, Bill; Lowery, Arthur

    2016-07-15

    We show that unscented Kalman filters can be used to mitigate local oscillator phase noise and to compensate carrier frequency offset in coherent single-carrier optical communication systems. A parallel processing architecture implementing the unscented Kalman filter is proposed, improving upon a previous parallelized linear Kalman filter (LKF) implementation. PMID:27420508

  7. Peptide-Carrier Conjugation

    DEFF Research Database (Denmark)

    Hansen, Paul Robert

    To produce antibodies against synthetic peptides it is necessary to couple them to a protein carrier. This chapter provides a nonspecialist overview of peptide-carrier conjugation. Furthermore, a protocol for coupling cysteine-containing peptides to bovine serum albumin is outlined.......To produce antibodies against synthetic peptides it is necessary to couple them to a protein carrier. This chapter provides a nonspecialist overview of peptide-carrier conjugation. Furthermore, a protocol for coupling cysteine-containing peptides to bovine serum albumin is outlined....

  8. 顾客集中与管理层治理--基于薪酬契约和代理成本的视角%Customer Concentration and Management Governance---Based on the Perspective of Compensation Contract and Agency Cost

    Institute of Scientific and Technical Information of China (English)

    杨风

    2016-01-01

    本文以创业板上市公司为研究样本,从薪酬契约和代理成本的视角,检验了顾客集中与管理层治理的关系。实证分析结果显示,顾客集中度与高管薪酬和代理成本存在显著负相关关系。结果表明:顾客集中显著影响公司薪酬契约,顾客集中降低了高管薪酬;顾客集中降低代理成本,减轻管理层代理冲突问题。这些研究结论丰富了公司治理的理论内容,同时对于缓解公司代理冲突、改善公司治理矛盾具有重要的现实意义。%Based on the manual data of listed companies on GEM , the paper examines the relationship between customer concentra-tion and management governance on the perspective of compensation contract and agency cost . Studies reveal that customer concentration has a significant negative impact on managerial compensation and agency cost . The results show that :customer concentration significantly influence compensation contracts and reduce executive pay ;customer concentration can reduce agency cost and the management agency conflict problem . Therefore , this study will be meaningful for corporate governance theory . At the same time , it also has an important re-alistic meaning to ease agency conflict and consummate corporate governance mechanism .

  9. Coase Competition and Compensation

    OpenAIRE

    Hal Varian

    1994-01-01

    I show that the Pigovian solution to a simple externalities problem and a particular Coasian solution can be viewed as competitive equilibria from different initial endowments. I also describe the ``compensation mechanism,'' a mechanism that implements either the Coasian or Pigovian solution as the outcome of an economically natural bargaining game.

  10. Asymmetric Carrier Random PWM

    DEFF Research Database (Denmark)

    Mathe, Laszlo; Lungeanu, Florin; Rasmussen, Peter Omand;

    2010-01-01

    This paper presents a new fixed carrier frequency random PWM method, where a new type of carrier wave is proposed for modulation. Based on the measurements, it is shown that the spread effect of the discrete components from the motor current spectra is very effective independent of the modulation...

  11. Compensation mechanism in liquid encapsulated Czochralski GaAs Importance of melt stoichiometry

    Science.gov (United States)

    Holmes, D. E.; Chen, R. T.; Elliott, K. R.; Kirkpatrick, C. G.; Yu, P. W.

    1982-01-01

    It is shown that the key to reproducible growth of undoped semi-insulating GaAs by the liquid encapsulated Czochralski (LEC) technique is the control over the melt stoichiometry. Twelve crystals were grown from stoichiometric and nonstoichiometric melts. The material was characterized by secondary ion mass spectrometry, localized vibrational mode far infrared spectroscopy, Hall-effect measurements, optical absorption, and photoluminescence. A quantitative model for the compensation mechanism in the semi-insulating material was developed based on these measurements. The free carrier concentration is controlled by the balance between EL2 deep donors and carbon acceptors; furthermore, the incorporation of EL2 is controlled by the melt stoichiometry, increasing as the As atom fraction in the melt increases. As a result, semi-insulating material can be grown only from melts above a critical As composition. The practical significance of these results is discussed in terms of achieving high yield and reproducibility in the crystal growth process.

  12. RELIABILITY OF LENTICULAR EXPANSION COMPENSATORS

    Directory of Open Access Journals (Sweden)

    Gabriel BURLACU,

    2011-11-01

    Full Text Available Axial lenticular compensators are made to take over the longitudinal heat expansion, shock , vibration and noise, made elastic connections for piping systems. In order to have a long life for installations it is necessary that all elements, including lenticular compensators, have a good reliability. This desire can be did by technology of manufactoring and assembly of compensators, the material for lenses and by maintenance.of compensator

  13. Firm performance and CEO compensation : Determinants of CEO compensation

    OpenAIRE

    Singh, Minu; Yavuz, Cigdem

    2015-01-01

    CEO compensation is a much discussed concept in the media and in the society in general. The center of the discussion is mostly around the high CEO compensations and the gaps between the compensation to the CEOs and to rest of the employees. As this is an interesting and topical concept, we hence wanted to examine how CEO compensation is determined in firms listed on the Oslo Stock Exchange. We wanted to examine if CEOs actually get their compensation for obtained firm performance, or if ther...

  14. Compensation Consultants and CEO Pay

    NARCIS (Netherlands)

    Kabir, Rezaul; Minhat, Marizah

    2014-01-01

    The study examines the practice of employing multiple compensation consultants. Examining data of a sample of UK companies over the period 2003–2006 we find that CEOs receive higher equity-based pay when firms employ more than one compensation consultant. An increase in the number of compensation co

  15. Strategic Promotion and Compensation.

    OpenAIRE

    Bernhardt, Dan

    1995-01-01

    Within a hierarchical firm structure, this paper details how the composition of a worker's skills and the nonobservability of a worker's ability affect wage and promotion paths. Promotion-based compensation schemes derive naturally from the worker's asymmetrically observed ability. Promotion takes place over time and is inefficient since employers strategically exploit their knowledge of an able worker's ability. Conversely, employers may be unable to efficiently demote and retain bad manager...

  16. Compensability index for compensation radiotherapy after treatment interruptions

    Directory of Open Access Journals (Sweden)

    Putora Paul

    2012-12-01

    Full Text Available Abstract Background The goal of our work was to develop a simple method to evaluate a compensation treatment after unplanned treatment interruptions with respect to their tumour- and normal tissue effect. Methods We developed a software tool in java programming language based on existing recommendations to compensate for treatment interruptions. In order to express and visualize the deviations from the originally planned tumour and normal tissue effects we defined the compensability index. Results The compensability index represents an evaluation of the suitability of compensatory radiotherapy in a single number based on the number of days used for compensation and the preference of preserving the originally planned tumour effect or not exceeding the originally planned normal tissue effect. An automated tool provides a method for quick evaluation of compensation treatments. Conclusions The compensability index calculation may serve as a decision support system based on existing and established recommendations.

  17. Compensability index for compensation radiotherapy after treatment interruptions

    International Nuclear Information System (INIS)

    The goal of our work was to develop a simple method to evaluate a compensation treatment after unplanned treatment interruptions with respect to their tumour- and normal tissue effect. We developed a software tool in java programming language based on existing recommendations to compensate for treatment interruptions. In order to express and visualize the deviations from the originally planned tumour and normal tissue effects we defined the compensability index. The compensability index represents an evaluation of the suitability of compensatory radiotherapy in a single number based on the number of days used for compensation and the preference of preserving the originally planned tumour effect or not exceeding the originally planned normal tissue effect. An automated tool provides a method for quick evaluation of compensation treatments. The compensability index calculation may serve as a decision support system based on existing and established recommendations

  18. Determinants of family employee work performance and compensation in family businesses

    OpenAIRE

    Van Der Merwe, Stephanus

    2009-01-01

    This study characterizes employee compensation in family owned and managed firms compared to that in non-family firms and professionally managed family firms. The general results show that employee compensation differs between firms. This is an important finding because to understand employee compensation designs it is necessary to understand the role of ownership concentration and management composition in the firm, since the compensation components are explicitly defined according to risk s...

  19. On the Theory of Compensation in Lithium drifted Semiconductor Detectors

    International Nuclear Information System (INIS)

    The lithium ion drift method produces detectors with a highly but not perfectly compensated intrinsic region. The amount of fixed space charge left in the depleted layer and its dependence on drift and clean-up parameters is of great practical interest. The imperfect compensation is mainly due to the presence in the depletion layer of thermally generated electron-hole pairs swept apart by the voltage applied to the detector during drift. A theoretical model is developed which takes into account the influence on the fixed space charge of mobile carrier generation and recombination. When recombination of free electrons and holes is negligible the theory predicts the formation of linear space charge gradients. When recombination is strong a constant space charge throughout a large part of the compensated layer may result. The theoretical calculations are compared with experimental findings. The influence of space charge on detector performance is discussed

  20. Fukushima: liability and compensation

    International Nuclear Information System (INIS)

    On 11 March 2011, Japan endured one of the worst natural disasters in its history when a massive earthquake struck the Pacific coast of the country and was followed by a tsunami which led to considerable loss of lives. It also led to a major accident at the Fukushima Daiichi nuclear power plant. Soon afterwards, the operator of the plant, Tokyo Electric Power Company (TEPCO), assumed responsibility and liability for the nuclear accident. On 28 April 2011, TEPCO established a dedicated contact line to provide consulting services for financial compensation related to the damage caused

  1. Carrier localization in gallium nitride

    Energy Technology Data Exchange (ETDEWEB)

    Wetzel, C. [Lawrence Berkeley National Lab., CA (United States)][California Univ., Berkeley, CA (United States); Walukiewicz, W. [Lawrence Berkeley National Lab., CA (United States); Haller, E.E. [Lawrence Berkeley National Lab., CA (United States)][California Univ., Berkeley, CA (United States)] [and others

    1996-09-01

    In wide bandgap GaN, a large number of interesting and important scientific questions remain to be answered. For example, the large free electron concentration reaching 10{sup 19} to 10{sup 20} cm{sup - 3} in nominally undoped material are ascribed to intrinsic defects because no chemical impurity has been found at such high concentrations. According to theoretical models, a nitrogen vacancy acts as a donor but its formation energy is very large in n-type materials, making this suggestion controversial. We have investigated the nature of this yet unidentified donor at large hydrostatic pressure. Results from infrared reflection and Raman scattering indicate strong evidence for localization of free carriers by large pressures. The carrier density is drastically decreased by two orders of magnitude between 20 and 30 GPa. Several techniques provide independent evidence for results in earlier reports and present the first quantitative analysis. A possible interpretation of this effect in terms of the resonant donor level is presented.

  2. The Interplay between Director Compensation and CEO Compensation

    OpenAIRE

    Dan Lin; Lu Lin

    2014-01-01

    This paper empirically examines the determinants of director compensation and CEO compensation and investigates whether director compensation has an effect on CEO compensation. Based on 713 firms (or 2,852 firm-years) between 2007 and 2010, we find that CEO tenure is related to the ability of the CEO in influencing the board’s pay determination process. However, sitting on the board does not strengthen the CEO’s power over the board during the pay negotiation process. More importantly, we...

  3. Superconductivity in compensated and uncompensated semiconductors

    Directory of Open Access Journals (Sweden)

    Youichi Yanase and Naoyuki Yorozu

    2008-01-01

    Full Text Available We investigate the localization and superconductivity in heavily doped semiconductors. The crossover from the superconductivity in the host band to that in the impurity band is described on the basis of the disordered three-dimensional attractive Hubbard model for binary alloys. The microscopic inhomogeneity and the thermal superconducting fluctuation are taken into account using the self-consistent 1-loop order theory. The superconductor-insulator transition accompanies the crossover from the host band to the impurity band. We point out an enhancement of the critical temperature Tc around the crossover. Further localization of electron wave functions leads to the localization of Cooper pairs and induces the pseudogap. We find that both the doping compensation by additional donors and the carrier increase by additional acceptors suppress the superconductivity. A theoretical interpretation is proposed for the superconductivity in the boron-doped diamond, SiC, and Si.

  4. Radio Science Measurements with Suppressed Carrier

    Science.gov (United States)

    Asmar, Sami; Divsalar, Dariush; Oudrhiri, Kamal

    2013-01-01

    Radio Science started when it became apparent with early Solar missions that occultations by planetary atmospheres would affect the quality of radio communications. Since then the atmospheric properties and other aspects of planetary science, solar science, and fundamental physics were studied by scientists. Radio Science data was always extracted from a received pure residual carrier (without data modulation). For some missions, it is very desirable to obtain Radio Science data from a suppressed carrier modulation. In this paper we propose a method to extract Radio Science data when a coded suppressed carrier modulation is used in deep space communications. Type of modulation can be BPSK, QPSK, OQPSK, MPSK or even GMSK. However we concentrate mostly on BPSK modulation. The proposed method for suppressed carrier simply tries to wipe out data that acts as an interference for Radio Science measurements. In order to measure the estimation errors in amplitude and phase of the Radio Science data we use Cramer-Rao bound (CRB). The CRB for the suppressed carrier modulation with non-ideal data wiping is then compared with residual carrier modulation under the same noise condition. The method of derivation of CRB for non-ideal data wiping is an innovative method that presented here. Some numerical results are provided for coded system.

  5. Executive Compensation, Incentives, and Risk

    OpenAIRE

    Jenter, Dirk

    2004-01-01

    This paper analyzes the link between equity-based compensation and created incentives by (1) deriving a measure of incentives suitable for both linear and non-linear compensation contracts, (2) analyzing the effect of risk on incentives, and (3) clarifying the role of the agent's private trading decisions in incentive creation. With option-based compensation contracts, the average pay-forperformance sensitivity is not an adequate measure of ex-ante incentives. Pay-for-performance covaries neg...

  6. Duchenne muscular dystrophy carriers

    International Nuclear Information System (INIS)

    By means of magnetic resonance imaging (MRI), the proton spin-lattice relaxation times (T1 values) of the skeletal muscles were measured in Duchenne muscular dystrophy (DMD) carriers and normal controls. The bound water fraction (BWF) was calculated from the T1 values obtained, according to the fast proton diffusion model. In the DMD carriers, T1 values of the gluteus maximus and quadriceps femoris muscles were significantly higher, and BWFs of these muscles were significantly lower than in normal control. Degenerative muscular changes accompanied by interstitial edema were presumed responsible for this abnormality. No correlation was observed between the muscle T1 and serum creatine kinase values. The present study showed that MRI could be a useful method for studying the dynamic state of water in both normal and pathological skeletal muscles. Its possible utility for DMD carrier detection was discussed briefly. (orig.)

  7. Shadow Detection and Compensation for Color Aerial Images

    Institute of Scientific and Technical Information of China (English)

    WANG Shugen; GUO Zejin; LI Deren

    2003-01-01

    A method for shadow detection and compensation for color aerial images is presented. It is considered that the intensity value of each image pixel is the product of illumination function and ground object reflection, and the shadowed regions on the image are mainly caused by the short of illumination, so the information compensation for the shadowed regions should concentrate on the illumination adjustment of concerned area on the basis of the analysis of whole image. The shadow detection and compensation procedure proposed by this paper consists of four steps.

  8. Compensations during Unsteady Locomotion.

    Science.gov (United States)

    Qiao, Mu; Jindrich, Devin L

    2014-12-01

    Locomotion in a complex environment is often not steady, but the mechanisms used by animals to power and control unsteady locomotion (stability and maneuverability) are not well understood. We use behavioral, morphological, and impulsive perturbations to determine the compensations used during unsteady locomotion. At the level both of the whole-body and of joints, quasi-stiffness models are useful for describing adjustments to the functioning of legs and joints during maneuvers. However, alterations to the mechanics of legs and joints often are distinct for different phases of the step cycle or for specific joints. For example, negotiating steps involves independent changes of leg stiffness during compression and thrust phases of stance. Unsteady locomotion also involves parameters that are not part of the simplest reduced-parameter models of locomotion (e.g., the spring-loaded inverted pendulum) such as moments of the hip joint. Extensive coupling among translational and rotational parameters must be taken into account to stabilize locomotion or maneuver. For example, maneuvers with morphological perturbations (increased rotational inertial turns) involve changes to several aspects of movement, including the initial conditions of rotation and ground-reaction forces. Coupled changes to several parameters may be employed to control maneuvers on a trial-by-trial basis. Compensating for increased rotational inertia of the body during turns is facilitated by the opposing effects of several mechanical and behavioral parameters. However, the specific rules used by animals to control translation and rotation of the body to maintain stability or maneuver have not been fully characterized. We initiated direct-perturbation experiments to investigate the strategies used by humans to maintain stability following center-of-mass (COM) perturbations. When walking, humans showed more resistance to medio-lateral perturbations (lower COM displacement). However, when running, humans

  9. A Lanchester model of submarine attack on a carrier battlegroup

    OpenAIRE

    Eagle, James N.

    1987-01-01

    A Lanchester model is developed for a battlegroup ASW engagement. Two variations are included. In the first, long-range missile firing submarines, short-range missile or torpedo firing submarines, and submarines firing only torpedoes distribute their attack uniformly over battlegroup escort ships and carriers. In the second variation, the attack is concentrated on the carriers.

  10. 电力线载波远程集中抄表系统在冀东油田的应用%Application of Remote Concentrated Metering System with Power Line Carrier Technology in Jidong Oilfield

    Institute of Scientific and Technical Information of China (English)

    穆宏; 纪玉荣

    2012-01-01

    Low voltage power line carrier technology is a kind of communication mode based on low - voltage power line for high -frequency signal. It uses lowvoltage power line as communication line to realize remote control and high speed data communication.%低压电力线载波技术是一种通过低压输电线路作为高频信号传输线路的通讯方式。它利用现有的低压电力线作为通讯线路,并把电力线通讯技术、网络技术和微控制器相结合,实现远程控制和高速数据的传输。

  11. Intestinal solute carriers

    DEFF Research Database (Denmark)

    Steffansen, Bente; Nielsen, Carsten Uhd; Brodin, Birger; Eriksson, André Huss; Andersen, Rikke; Frokjaer, Sven

    2004-01-01

    A large amount of absorptive intestinal membrane transporters play an important part in absorption and distribution of several nutrients, drugs and prodrugs. The present paper gives a general overview on intestinal solute carriers as well as on trends and strategies for targeting drugs and...

  12. Glycosylation of solute carriers

    DEFF Research Database (Denmark)

    Pedersen, Nis Borbye; Carlsson, Michael C; Pedersen, Stine Helene Falsig

    2016-01-01

    Solute carriers (SLCs) are one of the largest groups of multi-spanning membrane proteins in mammals and include ubiquitously expressed proteins as well as proteins with highly restricted tissue expression. A vast number of studies have addressed the function and organization of SLCs as well as...

  13. Information and Its Carriers.

    Science.gov (United States)

    Herrmann, F.; And Others

    1985-01-01

    Describes: (1) the structure of a data transmission source, carrier, and receiver; (2) a quantitative measure for the amount of data, followed by some quantitative examples of data transmission processes; (3) the concept of data current; (4) data containers; and (5) how this information can be used to structure physics courses. (JN)

  14. Sales Force Motivation and Compensation

    OpenAIRE

    Anca-Mihaela TEAU

    2013-01-01

    This article illustrate how sales managers can use sales incentives and compensations to motivate their sales team. To motivate sales people effectively, sales managers must have a thorough understanding of human needs and the concepts of motivation. They must also learn how to use the various forms of sales incentives and compensation to meet their salespeople’s needs.

  15. An overview of turbulence compensation

    NARCIS (Netherlands)

    Schutte, K.; Eekeren, A.W.M. van; Dijk, J.; Schwering, P.B.W.; Iersel, M. van; Doelman, N.J.

    2012-01-01

    In general, long range visual detection, recognition and identification are hampered by turbulence caused by atmospheric conditions. Much research has been devoted to the field of turbulence compensation. One of the main advantages of turbulence compensation is that it enables visual identification

  16. Primary-care physician compensation.

    Science.gov (United States)

    Olson, Arik

    2012-01-01

    This article reviews existing models of physician compensation and presents information about current compensation patterns for primary-care physicians in the United States. Theories of work motivation are reviewed where they have relevance to the desired outcome of satisfied, productive physicians whose skills and expertise are retained in the workforce. Healthcare reforms that purport to bring accountability for healthcare quality and value-rather than simply volume-bring opportunities to redesign primary-care physician compensation and may allow for new compensation methodologies that increase job satisfaction. Physicians are increasingly shunning the responsibility of private practice and choosing to work as employees of a larger organization, often a hospital. Employers of physicians are seeking compensation models that reward both productivity and value. PMID:22786738

  17. 38 CFR 3.459 - Death compensation.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Death compensation. 3.459..., Compensation, and Dependency and Indemnity Compensation Apportionments § 3.459 Death compensation. (a) Death compensation will be apportioned if the child or children of the deceased veteran are not in the custody of...

  18. [Vestibular compensation studies]. [Vestibular Compensation and Morphological Studies

    Science.gov (United States)

    Perachio, Adrian A. (Principal Investigator)

    1996-01-01

    The following topics are reported: neurophysiological studies on MVN neurons during vestibular compensation; effects of spinal cord lesions on VNC neurons during compensation; a closed-loop vestibular compensation model for horizontally canal-related MVN neurons; spatiotemporal convergence in VNC neurons; contributions of irregularly firing vestibular afferents to linear and angular VOR's; application to flight studies; metabolic measures in vestibular neurons; immediate early gene expression following vestibular stimulation; morphological studies on primary afferents, central vestibular pathways, vestibular efferent projection to the vestibular end organs, and three-dimensional morphometry and imaging.

  19. Compensated pulsed alternator

    International Nuclear Information System (INIS)

    This invention relates to an electromechanical energy converter with inertial energy storage. The device, a single phase, two or multi-pole alternator with stationary field coils, and a rotating armature is provided. The rotor itself may be of laminated steel for slower pulses or for faster pulses should be nonmagnetic and electrically nonconductive in order to allow rapid penetration of the field as the armature coil rotates. The armature coil comprises a plurality of power generating conductors mounted on the rotor. The alternator may also include a stationary or counterrotating compensating coil to increase the output voltage thereof and to reduce the internal impedance of the alternator at the moment of peak output. As the machine voltage rises sinusoidally, an external trigger switch is adapted to be closed at the appropriate time to create the desired output current from said alternator to an external load circuit, and as the output current passes through zero a self-commutating effect is provided to allow the switch to disconnect the generator from the external circuit

  20. Visible light carrier generation in co-doped epitaxial titanate films

    Energy Technology Data Exchange (ETDEWEB)

    Comes, Ryan B.; Smolin, Sergey Y.; Kaspar, Tiffany C.; Gao, Ran; Apgar, Brent A.; Martin, Lane W.; Bowden, Mark E.; Baxter, Jason; Chambers, Scott A.

    2015-03-02

    Perovskite titanates such as SrTiO3 (STO) exhibit a wide range of important functional properties, including high electron mobility, ferroelectricity—which may be valuable in photovoltaic applications—and excellent photocatalytic performance. The wide optical band gap of titanates limits their use in these applications, however, making them ill-suited for integration into solar energy harvesting technologies. Our recent work has shown that by doping STO with equal concentrations of La and Cr we can enhance visible light absorption in epitaxial thin films while avoiding any compensating defects. In this work, we explore the optical properties of photoexcited carriers in these films. Using spectroscopic ellipsometry, we show that the Cr3+ dopants, which produce electronic states immediately above the top of the O 2p valence band in STO reduce the direct band gap of the material from 3.75 eV to between 2.4 and 2.7 eV depending on doping levels. Transient reflectance measurements confirm that optically generated carriers have a recombination lifetime comparable to that of STO and are in agreement with the observations from ellipsometry. Finally, through photoelectrochemical yield measurements, we show that these co-doped films exhibit enhanced visible light photocatalysis when compared to pure STO.

  1. Visible light carrier generation in co-doped epitaxial titanate films

    Energy Technology Data Exchange (ETDEWEB)

    Comes, Ryan B., E-mail: ryan.comes@pnnl.gov; Kaspar, Tiffany C.; Chambers, Scott A. [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354 (United States); Smolin, Sergey Y.; Baxter, Jason B. [Department of Chemical and Biological Engineering, Drexel University, Philadelphia, Pennsylvania 19104 (United States); Gao, Ran [Department of Materials Science and Engineering, University of California-Berkeley, Berkeley, California 94720 (United States); Apgar, Brent A. [Department of Materials Science and Engineering, University of California-Berkeley, Berkeley, California 94720 (United States); Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Champaign, Illinois 61801 (United States); Martin, Lane W. [Department of Materials Science and Engineering, University of California-Berkeley, Berkeley, California 94720 (United States); Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Bowden, Mark E. [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99354 (United States)

    2015-03-02

    Perovskite titanates such as SrTiO{sub 3} (STO) exhibit a wide range of important functional properties, including ferroelectricity and excellent photocatalytic performance. The wide optical band gap of titanates limits their use in these applications; however, making them ill-suited for integration into solar energy harvesting technologies. Our recent work has shown that by doping STO with equal concentrations of La and Cr, we can enhance visible light absorption in epitaxial thin films while avoiding any compensating defects. In this work, we explore the optical properties of photoexcited carriers in these films. Using spectroscopic ellipsometry, we show that the Cr{sup 3+} dopants, which produce electronic states immediately above the top of the O 2p valence band in STO reduce the direct band gap of the material from 3.75 eV to 2.4–2.7 eV depending on doping levels. Transient reflectance spectroscopy measurements are in agreement with the observations from ellipsometry and confirm that optically generated carriers are present for longer than 2 ns. Finally, through photoelectrochemical methylene blue degradation measurements, we show that these co-doped films exhibit enhanced visible light photocatalysis when compared to pure STO.

  2. Hungarian students’ carrier aspirations

    Directory of Open Access Journals (Sweden)

    A.S. Gubik

    2014-06-01

    Full Text Available The article analyzes the students’ carrier aspiration, right after their graduation and five years after their studies. It examines the differences arising from the students’ family business background and their most important social variables (gender, age. Then the study highlights the effects of study field on the students’ intention. The direct effect of education on starting an enterprise is undiscovered in the literature, the paper deals with the influence of availability and services use, offered by higher institutions.

  3. An overview of turbulence compensation

    Science.gov (United States)

    Schutte, Klamer; van Eekeren, Adam W. M.; Dijk, Judith; Schwering, Piet B. W.; van Iersel, Miranda; Doelman, Niek J.

    2012-09-01

    In general, long range visual detection, recognition and identification are hampered by turbulence caused by atmospheric conditions. Much research has been devoted to the field of turbulence compensation. One of the main advantages of turbulence compensation is that it enables visual identification over larger distances. In many (military) scenarios this is of crucial importance. In this paper we give an overview of several software and hardware approaches to compensate for the visual artifacts caused by turbulence. These approaches are very diverse and range from the use of dedicated hardware, such as adaptive optics, to the use of software methods, such as deconvolution and lucky imaging. For each approach the pros and cons are given and it is indicated for which type of scenario this approach is useful. In more detail we describe the turbulence compensation methods TNO has developed in the last years and place them in the context of the different turbulence compensation approaches and TNO's turbulence compensation roadmap. Furthermore we look forward and indicate the upcoming challenges in the field of turbulence compensation.

  4. Effect of doping concentration and disorder on the mobility of carriers in organic light emitting diodes%掺杂浓度和无序对柔性有机发光二极管载流子迁移率的影响

    Institute of Scientific and Technical Information of China (English)

    陈雨璐; 侯晓远; 岑剡

    2011-01-01

    基于电荷分布的泊松方程和载流子输运方程,考虑最低能量非占据态和最高能量占据态的载流子态密度服从双高斯分布的模型,自洽地研究了掺杂浓度和无序对Alq3柔性有机发光二极管载流子迁移率的影响.发现掺杂浓度低于1×1020cm-3时,掺杂浓度对迁移率影响很小,迁移率几乎保持不变;当掺杂浓度大于1×1020cm-3时,载流子迁移率非线性增加,与实验结果很好一致.考虑不同无序度时,发现无序度的增加,相应的迁移率下降;低掺杂浓度下迁移率与无序度的大小关系不大,当掺杂浓度较高的时,无序度较小的材料迁移率增加较快.最终给出了柔性发光二极管器件的发光功率密度与电压关系,表明载流子浓度和无序相关的迁移率结果对制备高性能的柔性有机发光二极管具有指导意义.%Based on the Poisson' s equation of charge distribution and the transport equation of carriers, the effect of doping concentration and disordered degree on the mobility of carriers in the Alq3 flexible organic light-emitting diodes has been studied self-consistently.The density of states of the carriers was described with the double Gaussian distributions because of the energy disorders of organic molecules.It was found that the carrers'mobility is almost fixed with doping concentration smaller than 1 × 1020cm-3.The carriers'mobility increased nonlinearly when the doping concentration was larger than 1 ×1020cm-3, in well agreement with the experimental results.It was also showed that the increase of mobility as a function of doping concentration for smaller disordered degree is faster than that for larger disordered one.With low doping concentration, the disordered degree has little effect on the mobility.Finally,the doping concentration and the disorder degree dependence of the mobility is used to simulate the variations of the luminescence power density of the device with the voltage bias.It was

  5. Comparison of human solute carriers

    OpenAIRE

    Schlessinger, Avner; Matsson, Pär; Shima, James E.; Pieper, Ursula; Yee, Sook Wah; Kelly, Libusha; Apeltsin, Leonard; Stroud, Robert M.; Ferrin, Thomas E; Giacomini, Kathleen M.; Sali, Andrej

    2010-01-01

    Solute carriers are eukaryotic membrane proteins that control the uptake and efflux of solutes, including essential cellular compounds, environmental toxins, and therapeutic drugs. Solute carriers can share similar structural features despite weak sequence similarities. Identification of sequence relationships among solute carriers is needed to enhance our ability to model individual carriers and to elucidate the molecular mechanisms of their substrate specificity and transport. Here, we desc...

  6. Effect of Mg doping on the structural and free-charge carrier properties of InN films

    International Nuclear Information System (INIS)

    We present a comprehensive study of free-charge carrier and structural properties of two sets of InN films grown by molecular beam epitaxy and systematically doped with Mg from 1.0 × 1018 cm−3 to 3.9 × 1021 cm−3. The free electron and hole concentration, mobility, and plasmon broadening parameters are determined by infrared spectroscopic ellipsometry. The lattice parameters, microstructure, and surface morphology are determined by high-resolution X-ray diffraction and atomic force microscopy. Consistent results on the free-charge carrier type are found in the two sets of InN films and it is inferred that p-type conductivity could be achieved for 1.0 × 1018 cm−3 ≲ [Mg] ≲ 9.0 × 1019 cm−3. The systematic change of free-charge carrier properties with Mg concentration is discussed in relation to the evolution of extended defect density and growth mode. A comparison between the structural characteristics and free electron concentrations in the films provides insights in the role of extended and point defects for the n-type conductivity in InN. It further allows to suggest pathways for achieving compensated InN material with relatively high electron mobility and low defect densities. The critical values of Mg concentration for which polarity inversion and formation of zinc-blende InN occurred are determined. Finally, the effect of Mg doping on the lattice parameters is established and different contributions to the strain in the films are discussed

  7. Wafer-scale characterization of carrier dynamics in graphene

    DEFF Research Database (Denmark)

    Buron, Jonas Christian Due; Petersen, Dirch Hjorth; Bøggild, Peter;

    2015-01-01

    The electronic properties of single-layer graphene, such as surface conductance, carrier concentration, scattering time and mobility, can be characterized in a noncontact manner by THz time-domain spectroscopy. Standard spectroscopic imaging reveals the AC conductance over large areas with a few...... hundred μm resolution, and spectroscopic imaging on back-gated graphene allows for extraction of both the carrier concentration and the mobility. We find that spatial variations of the conductance of single-layer CVD-grown graphene are predominantly due to variations in mobility rather than in carrier...

  8. Blind Estimation of Multiple Carrier Frequency Offsets

    CERN Document Server

    Yu, Yuanning; Poor, H Vincent; Koivunen, Visa

    2007-01-01

    Multiple carrier-frequency offsets (CFO) arise in a distributed antenna system, where data are transmitted simultaneously from multiple antennas. In such systems the received signal contains multiple CFOs due to mismatch between the local oscillators of transmitters and receiver. This results in a time-varying rotation of the data constellation, which needs to be compensated for at the receiver before symbol recovery. This paper proposes a new approach for blind CFO estimation and symbol recovery. The received base-band signal is over-sampled, and its polyphase components are used to formulate a virtual Multiple-Input Multiple-Output (MIMO) problem. By applying blind MIMO system estimation techniques, the system response is estimated and used to subsequently transform the multiple CFOs estimation problem into many independent single CFO estimation problems. Furthermore, an initial estimate of the CFO is obtained from the phase of the MIMO system response. The Cramer-Rao Lower bound is also derived, and the la...

  9. Carrier transport uphill. I. General

    DEFF Research Database (Denmark)

    Rosenberg, T; Wilbrandt, W

    1963-01-01

    A quantitative treatment of a carrier pump operating with two carrier forms C and Z is presented. Asymmetric metabolic reactions are assumed to transform Z into C on one and C into Z on the other side of the membrane, establishing a carrier cycle. The kinetical consequences of this mechanism are...

  10. Modification of Carrier Gas Stream to Improve 13C/12C Isotopic Accuracy in Cavity Ring-Down Spectroscopy-Based Measurements of Low-Concentration Dissolved Carbon Samples

    Science.gov (United States)

    Conaway, C. H.; Morkner, P.; Thomas, B.; Saad, N.

    2013-12-01

    Determining isotopic composition of dissolved organic and inorganic carbon in natural waters is of critical importance to a broad set of scientific objectives. The routine analysis of these sample types can be expensive and in the past has been limited predominantly to laboratories capable of high-precision isotope ratio mass spectrometric analysis. More recently, cavity ring-down spectroscopy (CRDS) has provided an alternative instrumental means for characterizing these samples. One challenge with these types of is that the CRDS can show a non-linear response in d13C at low carbon concentrations (<0.5 mM). Here we present a new approach using a modification of a total organic carbon-cavity ring-down spectroscopy (TOC-CRDS) continuous flow system by adding a background stream of carbon dioxide of known isotopic composition to the CRDS analytical train. The isotopic carbon values generated by the CRDS are then corrected using a two-component isotopic mixing model. This modification is useful in reducing bias towards lighter carbon isotopic values when measuring samples with low carbon concentration, such as natural waters with either dissolved organic or inorganic carbon concentrations of less than 0.5 mM, and does not introduce substantial bias for higher concentration samples.

  11. 33 CFR 136.113 - Other compensation.

    Science.gov (United States)

    2010-07-01

    ...) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; CLAIMS... claimant must include an accounting, including the source and value, of all other compensation...

  12. Maintainable substrate carrier for electroplating

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chen-An; Abas, Emmanuel Chua; Divino, Edmundo Anida; Ermita, Jake Randal G.; Capulong, Jose Francisco S.; Castillo, Arnold Villamor; Ma, Diana Xiaobing

    2016-08-02

    One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The carrier includes a non-conductive carrier body on which the substrates are placed and conductive lines embedded within the carrier body. A plurality of conductive clip attachment parts are attached in a permanent manner to the conductive lines embedded within the carrier body. A plurality of contact clips are attached in a removable manner to the clip attachment parts. The contact clips hold the substrates in place and conductively connecting the substrates with the conductive lines. Other embodiments, aspects and features are also disclosed.

  13. CEO Compensation and Bank Performance

    OpenAIRE

    Athar, Iqbal; Khan, Muhammad Irfan; Ali, Saffar

    2012-01-01

    This study sets out to discover the determinants of compensation of the chief executive officers in the banking industry of Pakistan. Accounting based performance measures and size of the firm have been used as predictors. Results of the study are consistent with arguments, suggesting significant and positive impact of size (assets) of the firm on CEO compensation while no association is found with either of the performance measure of the firm except income before tax (IBT). Return on Assets ...

  14. BOARD STRUCTURE AND CEO COMPENSATION

    OpenAIRE

    Anjam, Zeshan

    2010-01-01

    This study examines the relationship between board structure (non executive directors, executive directors and independent non executive directors) and CEO compensation, in the context of an emerging and developing economy of Pakistan in year 2009. Most of the previous studies about board structure and CEO compensation are based in developed economies but this study is about a developing and emerging economy Pakistan and possibly this attempt will contributes to literature. Data for 86 listed...

  15. Recent trends in compensation practices

    OpenAIRE

    David E. Lebow; Louise Sheiner; Lawrence Slifman; Martha Starr-McCluer

    1999-01-01

    According to some accounts, compensation practices have recently been undergoing marked changes, with an increasing number of firms said to be substituting lump-sum payments for regular pay increases, allowing for greater variability of remuneration across individuals or groups, and making greater use of profit sharing or stock options. Many of these practices are outside the scope of the typical measures of economy-wide compensation growth. Moreover, intensified use of these schemes ought to...

  16. Option compensation and industry competition

    OpenAIRE

    Wong, KP; Stoughton, NM

    2009-01-01

    Compensation policy has become one of the most important ingredients of corporate governance. In this paper we take a new look at the issue, by contrasting the use of options with that of stock. We do this by integrating the repricing or resetting aspect of options with that of industrial structure. We show that industry competition may play an important role in dictating which form of compensation is optimal. When aggressive competition for key professional staff is an issue, the flexibility...

  17. Compensation: current thinking in France

    International Nuclear Information System (INIS)

    Nuclear third party Liability law constitutes an exception to the general law of tort liability in several respects, notably the channelling of all liability to the nuclear operator even where the operator has not been at fault, and the obligation imposed upon the operator to provide financial security covering its liability. In addition, French law gives priority to compensating personal injuries, fixes the list of radioactively-induced diseases and establishes compensation based on a lump sum payment. The Group examined how these principles could be concretely implemented. It recommended two actions be taken before all else and as soon as possible: the creation of a medical group responsible for ongoing health surveillance apart from any possibility of an accident; and the establishment of a standard compensation agreement which would be prepared in advance and in consultation with interested stakeholders, to allow for compensation to be distributed quickly. Concerning organisational matters, the Group proposed setting up a 'Monitoring Committee' which would bring together all interested parties. The Group also investigated the possibility of setting up a 'One-Stop Shop' which would enable victims to contact one single agency in their quest for compensation for damage suffered, regardless of the source of the compensation funds. (author)

  18. Autonomous component carrier selection

    DEFF Research Database (Denmark)

    Garcia, Luis Guilherme Uzeda; Pedersen, Klaus; Mogensen, Preben

    2009-01-01

    in local areas, basing our study case on LTE-Advanced. We present extensive network simulation results to demonstrate that a simple and robust interference management scheme, called autonomous component carrier selection allows each cell to select the most attractive frequency configuration; improving...... management and efficient system operation. Due to the expected large number of user-deployed cells, centralized network planning becomes unpractical and new scalable alternatives must be sought. In this article, we propose a fully distributed and scalable solution to the interference management problem...

  19. Emission spectrographic carrier distillation techniques for the determination of trace elements in nuclear fuel materials

    International Nuclear Information System (INIS)

    Emission spectrography is widely used in quality control of nuclear fuels for the determination of trace metal impurities in uranium. Carrier distillation technique with a suitable carrier is commonly used for routine quantometric analysis. The limits of detection obtained by other methods involving chemical separation and pre-concentration are better than those for the carrier distillation technique. In this study investigations were made to evaluate various carrier distillation techniques and to develope a suitable technique for achieving optimum sensitivity. (authors)

  20. Frequency Domain LED Compensation for Nonlinearity Mitigation in DMT Systems

    OpenAIRE

    Peng, Linning; Haese, Sylvain; Hélard, Maryline

    2013-01-01

    In this letter, a novel linear frequency-domain compensation (FDC) of the resonant cavity light emitting diode (RC-LED) for discrete multi-tone (DMT) modulation has been used for the first time in the nonlinearity mitigation of step-index polymer optical fiber (SI-POF) communication systems. The proposed FDC method can be easily implemented in any multi-carrier communication system. Compared to the classical DMT scheme, FDC DMT benefits from higher power efficiency in terms of clipping for pe...

  1. Point defects and electric compensation in gallium arsenide single crystals

    International Nuclear Information System (INIS)

    In the present thesis the point-defect budget of gallium arsenide single crystals with different dopings is studied. It is shown, in which way the concentration of the single point defects depende on the concentration of the dopants, the stoichiometry deviation, and the position of the Fermi level. For this serve the results of the measurement-technical characterization of a large number of samples, in the fabrication of which these parameters were directedly varied. The main topic of this thesis lies in the development of models, which allow a quantitative description of the experimentally studied electrical and optical properties of gallium arsenide single crystals starting from the point-defect concentrations. Because from point defects charge carriers can be set free, their concentration determines essentially the charge-carrier concentration in the bands. In the ionized state point defects act as scattering centers for free charge carriers and influence by this the drift mobility of the charge carriers. A thermodynamic modeling of the point-defect formation yields statements on the equilibrium concentrations of the point defects in dependence on dopant concentration and stoichiometry deviation. It is show that the electrical properties of the crystals observed at room temperature result from the kinetic suppression of processes, via which the adjustment of a thermodynamic equilibrium between the point defects is mediated

  2. X-Chromosome dosage compensation.

    Science.gov (United States)

    Meyer, Barbara J

    2005-01-01

    In mammals, flies, and worms, sex is determined by distinctive regulatory mechanisms that cause males (XO or XY) and females (XX) to differ in their dose of X chromosomes. In each species, an essential X chromosome-wide process called dosage compensation ensures that somatic cells of either sex express equal levels of X-linked gene products. The strategies used to achieve dosage compensation are diverse, but in all cases, specialized complexes are targeted specifically to the X chromosome(s) of only one sex to regulate transcript levels. In C. elegans, this sex-specific targeting of the dosage compensation complex (DCC) is controlled by the same developmental signal that establishes sex, the ratio of X chromosomes to sets of autosomes (X:A signal). Molecular components of this chromosome counting process have been defined. Following a common step of regulation, sex determination and dosage compensation are controlled by distinct genetic pathways. C. elegans dosage compensation is implemented by a protein complex that binds both X chromosomes of hermaphrodites to reduce transcript levels by one-half. The dosage compensation complex resembles the conserved 13S condensin complex required for both mitotic and meiotic chromosome resolution and condensation, implying the recruitment of ancient proteins to the new task of regulating gene expression. Within each C. elegans somatic cell, one of the DCC components also participates in the separate mitotic/meiotic condensin complex. Other DCC components play pivotal roles in regulating the number and distribution of crossovers during meiosis. The strategy by which C. elegans X chromosomes attract the condensin-like DCC is known. Small, well-dispersed X-recognition elements act as entry sites to recruit the dosage compensation complex and to nucleate spreading of the complex to X regions that lack recruitment sites. In this manner, a repressed chromatin state is spread in cis over short or long distances, thus establishing the

  3. 48 CFR 970.2270 - Unemployment compensation.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Unemployment compensation... Unemployment compensation. (a) Each state has its own unemployment compensation system to provide payments to... unemployment compensation benefits through a payroll tax on employers. Most DOE contractors are subject to...

  4. An Experimental Study of the Accuracy of Compensation in Lithium Drifted Germanium Detectors

    International Nuclear Information System (INIS)

    The nature and magnitude of the space charge existing in the compensated layer of lithium drifted germanium detectors has been studied as a function of drifted depth and of the electric field applied during drift. Experimental values were obtained from the dependence of detector capacitance on applied bias. In most cases there was a linear space charge gradient in the compensated layer. When small electric fields were applied to deep compensated layers, the space charge became constant throughout a large part of the compensated layer. There is some evidence for a strong decrease of mobile carrier recombination lifetime with increasing drifted depth, possibly down to a few microseconds for drifted depths of the order of 7 mm. The experimental results of the investigation are to a large extent in good agreement with theory

  5. On international compensations for environmental stocks

    OpenAIRE

    Stähler, Frank

    1993-01-01

    This paper sheds some light on the possible implications of compensations which are paid for the maintenance of an environmental stock. It shows that serious complications can arise if the resource-owner can vary the compensation price. In that case, extraction-driven stock preservation policies can conflict with compensation-driven ones and imply instability. Whether compensation policies can neglect this aspect depends crucially on the credibility of sticky compensation prices.

  6. LIQUIFIED NATURAL GAS (LNG CARRIERS

    Directory of Open Access Journals (Sweden)

    Daniel Posavec

    2010-12-01

    Full Text Available Modern liquefied natural gas carriers are double-bottom ships classified according to the type of LNG tank. The tanks are specially designed to store natural gas cooled to -161°C, the boiling point of methane. Since LNG is highly flammable, special care must be taken when designing and operating the ship. The development of LNG carriers has begun in the middle of the twentieth century. LNG carrier storage space has gradually grown to the current maximum of 260000 m3. There are more than 300 LNG carriers currently in operation (the paper is published in Croatian.

  7. Host state incentives and compensation:

    International Nuclear Information System (INIS)

    After reviewing several options for selecting a host state, the Commission elected to proceed with anoption that builds upon developing grass-roots acceptance and support. To foster such support the Commission has adopted an incentives and compensation package. The purpose of the package is that the incentives and compensations offered are designed to encourage an objective and unbiased review of accepting the responsibilities of a host state or community, and the package helps to guarantee that a facility will become a state/community asset and not impose economic, environmenta, or social hardships for the host community. This report, which describes the Commission's host state incentive and compensation package, the monetary benefit to the host community and state will be substantial. Community benefits will exceed $40 million over 20 years and benefits to the state will be approximately $24 million over the 20-year expected life of the facility. 10 refs., 4 tabs

  8. Electronic amplifiers for automatic compensators

    CERN Document Server

    Polonnikov, D Ye

    1965-01-01

    Electronic Amplifiers for Automatic Compensators presents the design and operation of electronic amplifiers for use in automatic control and measuring systems. This book is composed of eight chapters that consider the problems of constructing input and output circuits of amplifiers, suppression of interference and ensuring high sensitivity.This work begins with a survey of the operating principles of electronic amplifiers in automatic compensator systems. The succeeding chapters deal with circuit selection and the calculation and determination of the principal characteristics of amplifiers, as

  9. Adaptive Motion Compensation in Radiotherapy

    CERN Document Server

    Murphy, Martin J

    2011-01-01

    External-beam radiotherapy has long been challenged by the simple fact that patients can (and do) move during the delivery of radiation. Recent advances in imaging and beam delivery technologies have made the solution--adapting delivery to natural movement--a practical reality. Adaptive Motion Compensation in Radiotherapy provides the first detailed treatment of online interventional techniques for motion compensation radiotherapy. This authoritative book discusses: Each of the contributing elements of a motion-adaptive system, including target detection and tracking, beam adaptation, and pati

  10. Depth Compensated Spectral Domain Optical Coherence Tomography via Digital Compensation

    CERN Document Server

    Boroomand, Ameneh; Shafiee, Mohammad Javad; Bizheva, Kostadinka; Wong, Alexander

    2015-01-01

    Spectral Domain Optical Coherence Tomography (SD-OCT) is a well-known imaging modality which allows for \\textit{in-vivo} visualization of the morphology of different biological tissues at cellular level resolutions. The overall SD-OCT imaging quality in terms of axial resolution and Signal-to-Noise Ratio (SNR) degrades with imaging depth, while the lateral resolution degrades with distance from the focal plane. This image quality degradation is due both to the design of the SD-OCT imaging system and the optical properties of the imaged object. Here, we present a novel Depth Compensated SD-OCT (DC-OCT) system that integrates a Depth Compensating Digital Signal Processing (DC-DSP) module to improve the overall imaging quality via digital compensation. The designed DC-DSP module can be integrated to any SD-OCT system and is able to simultaneously compensate for the depth-dependent loss of axial and lateral resolutions, depth-varying SNR, as well as sidelobe artifact for improved imaging quality. The integrated D...

  11. Superconductivity in carrier-doped silicon carbide

    Directory of Open Access Journals (Sweden)

    Takahiro Muranaka, Yoshitake Kikuchi, Taku Yoshizawa, Naoki Shirakawa and Jun Akimitsu

    2008-01-01

    Full Text Available We report growth and characterization of heavily boron-doped 3C-SiC and 6H-SiC and Al-doped 3C-SiC. Both 3C-SiC:B and 6H-SiC:B reveal type-I superconductivity with a critical temperature Tc=1.5 K. On the other hand, Al-doped 3C-SiC (3C-SiC:Al shows type-II superconductivity with Tc=1.4 K. Both SiC:Al and SiC:B exhibit zero resistivity and diamagnetic susceptibility below Tc with effective hole-carrier concentration n higher than 1020 cm−3. We interpret the different superconducting behavior in carrier-doped p-type semiconductors SiC:Al, SiC:B, Si:B and C:B in terms of the different ionization energies of their acceptors.

  12. High carrier mobilities in black diamond

    Science.gov (United States)

    Williams, Oliver A.; Jackman, Richard B.; Nebel, Christoph; Foord, John S.

    2003-03-01

    Hydrogen plasma treatment of diamond renders the surface p-type, with the carriers emerging with little thermal activation, in sharp contrast to the use of boron for the formation of p-type material. To date, it has been thought that only the highest quality 'white' polycrystalline material is useful for electronic device applications, with many regarding single-crystal diamond as ultimately the substrate material of choice. In this paper it is shown that when p-type material is produced through hydrogenation, this is not the case. 'Black' polycrystalline diamond, which can be grown much more rapidly than white, shows carrier concentrations and mobility values similar to both white polycrystalline diamond and single-crystal material. This result has important implications for the provision of low-cost black-diamond substrates for device applications.

  13. Annual Pay and Compensation Report.

    Science.gov (United States)

    Vocino, Joe

    2003-01-01

    Presents results of the 2002 Human Resource Management Compensation Survey (n=1,084) indicating that salaries for training and development professionals increased only 1.8 percent over 2001. Tables depict salaries at various levels, by geographic area, and by industry. (JOW)

  14. Can Education Compensate for Society?

    Science.gov (United States)

    Pring, Richard

    2011-01-01

    The extent to which education can compensate for social disadvantage is a matter of political controversy, especially in the context of policies for social mobility. On the one hand, to blame poor achievement on social class or poverty was seen to dodge the professional responsibility of teachers. On the other, the strong correlation between…

  15. Psychology of Pay and Compensation

    NARCIS (Netherlands)

    Thierry, Hk.; Smelser, N.J.; Baltes, P.B.

    2002-01-01

    In most industrialized countries the compensation, of managers and employees is structured along quite comparable patterns. One part consists of base pay, a second part of results-oriented pay, and a third part of secondary labor conditions. In many instances part four is composed of perquisites: be

  16. Compensation for oil pollution damage

    Science.gov (United States)

    Matugina, E. G.; Glyzina, T. S.; Kolbysheva, Yu V.; Klyuchnikov, A. S.; Vusovich, O. V.

    2015-11-01

    The commitment of national industries to traditional energy sources, as well as constantly growing energy demand combined with adverse environmental impact of petroleum production and transportation urge to establish and maintain an appropriate legal and administrative framework for oil pollution damage compensation. The article considers management strategies for petroleum companies that embrace not only production benefits but also environmental issues.

  17. Background compensation methodologies for contamination monitoring systems

    International Nuclear Information System (INIS)

    Radiation surveillance program in the various nuclear facilities incorporate contamination monitoring as an important component. Contamination monitoring programs constitute monitoring for alpha and beta contamination of the physical entities associated with the working personnel that include his hands, feet, clothing, shoes as well as the general surface areas in the working environment like floors. All these measurements are fraught with the contribution of the ambient gamma background radiation fields. These inhibit a proper and precise estimation of the contamination concentration being monitored. This paper investigates the efficacy of two methodologies that have been incorporated in two of the contamination monitoring systems developed in the Division. In the first system discussed, a high degree of gamma compensation has been achieved for an uniform exposure of the order of 50 nSv/hr to 100 mSv/hr. In the second system discussed, the degree of gamma compensation achieved is equal to those dictated by the statistical nature of the uncertainties associated with the subtraction of background from the source data. These two methods can be very effectively employed depending on the application requirement. A minimum detection level equivalent to 0.37 Bq/cdm2 has been achieved in both these cases

  18. A Magnetic Disturbance Compensation Method Based on Magnetic Dipole Magnetic Field Distributing Theory

    Institute of Scientific and Technical Information of China (English)

    YANG Yun-tao; SHI Zhi-yong; L(U) Jian-gang; GUAN Zhen-zhen

    2009-01-01

    The interference of carrier magnetic field to geomagnetic field has been a difficult problem for a long time, which influences on the deviation of navigation compass and the error of geomagnetic measurement. To increase the geomagnetic measuring accuracy required for the geomagnetic matching localization, the strategy to eliminate the effect of connatural and induced magnetic fields of carrier on the geomagnetic measuring accuracy is investigated. The magnetic-dipoles magnetic field distributing theory is used to deduce the magnetic composition in the position of the sensor installed on the carrier. A geomagnetic measurement model is established by using the measuring data with the ideal sensor. Considering the magnetic disturbance of carrier and the error of sensor, a geomagnetic measuring compensation model is built. This model can be used to compensate the errors of carrier magnetic field and magnetic sensor in any case and its parameters have clear or specific physical meaning. The experimented results show that the model has higher geomagnetic measuring accuracy than that of others.

  19. 75 FR 76079 - Sound Incentive Compensation Guidance

    Science.gov (United States)

    2010-12-07

    ... incentive compensation practices in the banking industry by providing a common prudential foundation for incentive compensation arrangements across banking organizations and promoting the overall movement of the industry towards better practices. Supervisory action could play a critical role in addressing...

  20. 75 FR 53023 - Sound Incentive Compensation Guidance

    Science.gov (United States)

    2010-08-30

    ... incentive compensation practices in the banking industry by providing a common prudential foundation for incentive compensation arrangements across banking organizations and promoting the overall movement of the industry towards better practices. Supervisory action could play a critical role in addressing...

  1. 75 FR 22679 - Sound Incentive Compensation Guidance

    Science.gov (United States)

    2010-04-29

    ... incentive compensation practices in the banking industry by providing a common prudential foundation for incentive compensation arrangements across banking organizations and promoting the overall movement of the industry towards better practices. Supervisory action could play a critical role in addressing...

  2. Kinetics of Ca2+ carrier in rat liver mitochondria.

    Science.gov (United States)

    Bragadin, M; Pozzan, T; Azzone, G F

    1979-12-25

    The rate of aerobic Ca2+ transport is limited by the rate of the H+ pump rather than by the Ca2+ carrier. The kinetics of the Ca2+ carrier has therefore been studied by using the K+ diffusion potential as the driving force. The apparent Vmax of the Ca2+ carrier is, at 20 degrees C, about 900 nmol (mg of protein)-1 min-1, more than twice the rate of the H+ pump. The apparent Vmax is depressed by Mg2+ and Li+. This supports the view that the electrolytes act as noncompetitive inhibitors of the Ca2+ carrier. The degree of sigmoidicity of the kinetics of Ca2+ transport increases with the lowering of the temperature and proportionally with the concentration of impermeant electrolytes such as Mg2+ and Li+ but not choline. The effects of temperature and of electrolyte do not support the view that the sigmoidicity is due to modifications of the surface potential. Rather, they suggest that Ca2+ transport occurs through a multisubunit carrier, where cooperative phenomena are the result of ligand-induced conformational changes due to the interaction of several allosteric effectors with the carrier subunits. In contrast with La3+ which acts as a competitive inhibitor, Ruthenium Red affects the kinetics by inducing phenomena both of positive and of negative cooperativity. The Ruthenium Red induced kinetics has been reproduced through curve-fitting procedures by applying the Koshland sequential interaction hypothesis to a four-subunit Ca2+ carrier model. PMID:42437

  3. Carrier transport uphill. I. General

    DEFF Research Database (Denmark)

    Rosenberg, T; Wilbrandt, W

    1963-01-01

    A quantitative treatment of a carrier pump operating with two carrier forms C and Z is presented. Asymmetric metabolic reactions are assumed to transform Z into C on one and C into Z on the other side of the membrane, establishing a carrier cycle. The kinetical consequences of this mechanism are...... worked out with respect to net transport rate, initial rate, unidirectional fluxes including back-flow through the pump, maximum accumulation ratio, competitive inhibition and acceleration, counter transport, and metabolic poisoning. The energetics of the system are treated. The fact that the system...

  4. CEO Compensation in Canada, 1971-2008

    OpenAIRE

    Patrice Gelinas; Lisa Baillargeon

    2013-01-01

    This paper draws from a unique database spanning over 35 years of Canadian CEOs’ compensation to explorethe interplay among: the information available to boards of directors of Canadian companies for makingexecutive pay decisions, the Canadian business environment, and the compensation that Canadian CEOsreceived. We find a very strong correlation between Canadian CEOs’ compensation and the amount ofinformation on CEO compensation available to boards of directors. We further note that the evol...

  5. Basic Stand Alone Carrier Line Items PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Carrier Line Items Public Use Files (PUF) with information from Medicare Carrier claims. The CMS BSA Carrier Line...

  6. High hole concentration in p-type AlGaN by indium-surfactant-assisted Mg-delta doping

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yingda; Wu, Hualong; Han, Enze; Yue, Guanglong; Chen, Zimin; Wu, Zhisheng; Wang, Gang; Jiang, Hao, E-mail: stsjiang@mail.sysu.edu.cn [State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275 (China)

    2015-04-20

    High hole concentration was achieved in Mg-doped Al{sub x}Ga{sub 1−x}N (x ∼ 0.4) by using indium-surfactant-assisted delta doping method. A maximum carrier concentration of 4.75 × 10{sup 18 }cm{sup −3} was obtained, which is three times higher than that of the conventionally delta-doped sample. Sheet resistivity as low as 2.46 × 10{sup 4} Ω/sq was realized, benefiting from the high hole concentration (p). Analysis results show that the Mg incorporation is effectively enhanced, while the compensation ratio and acceptor activation energy (E{sub A}) are significantly reduced by using In surfactant. It was also found that the In surfactant may induce stronger valence-band modulation, contributing to the decrease of E{sub A} and the increase of p.

  7. High hole concentration in p-type AlGaN by indium-surfactant-assisted Mg-delta doping

    International Nuclear Information System (INIS)

    High hole concentration was achieved in Mg-doped AlxGa1−xN (x ∼ 0.4) by using indium-surfactant-assisted delta doping method. A maximum carrier concentration of 4.75 × 1018 cm−3 was obtained, which is three times higher than that of the conventionally delta-doped sample. Sheet resistivity as low as 2.46 × 104 Ω/sq was realized, benefiting from the high hole concentration (p). Analysis results show that the Mg incorporation is effectively enhanced, while the compensation ratio and acceptor activation energy (EA) are significantly reduced by using In surfactant. It was also found that the In surfactant may induce stronger valence-band modulation, contributing to the decrease of EA and the increase of p

  8. Dynamic Phase Compensation of wind turbines

    DEFF Research Database (Denmark)

    Soerensen, P.; Skaarup, J.; Iov, Florin

    2004-01-01

    This paper describes a dynamic phase compensation unit for a wind turbine with directly connected induction generators. The compensation unit is based on thyristor switched capacitors, where conventional wind turbine compensations use mechanical contactors to switch the capacitors. The unit modules...... are tested and simulated, and preliminary studies on the impact on power quality are performed....

  9. A model capturing ethics and executive compensation

    OpenAIRE

    Gago Rodríguez, Susana; Rodgers, Waymond

    2003-01-01

    This article develops and applies a knowledge-based framework for understanding and interpreting executive compensation under the rubric of ethical consideration. This framework classifies six major ethical considerations that reflect issues in compensation design. We emphasize that these six ethical considerations are influenced by liberty and equality concepts. This framework helps to highlight areas where executive compensation has not been well spelled out

  10. Incentives, School Organization and Teacher Compensation.

    Science.gov (United States)

    Odden, Allan

    In order for teacher compensation to serve as an incentive that reinforces broader organizational goals, the norms of the compensation structure must be aligned with the norms of the school organization. The first section of this paper presents a brief overview of changes in teacher compensation from 1820 to 1950. It describes how such changes…

  11. Development of watershed compensation programs

    International Nuclear Information System (INIS)

    British Columbia Hydro is developing fish and wildlife watershed compensation programs to address water license requirements of recent hydroelectric developments and outstanding issues associated with older projects. Historically, no funding was provided for environmental impacts. In more recent times, a one-time payment was made to the appropriate government agencies. With no long-term commitment by B.C. Hydro, fish and wildlife resource needs were often not addressed, leading to the degradation or loss of the resource and the perception that B.C. Hydro was not addressing its responsibilities with respect to other water users. B.C. Hydro's activities are reviewed with respect to developing ongoing fisheries compensation or mitigation programs through trust funds that ensure a long term commitment towards replacing or improving, and maintaining fish resources associated with B.C. Hydro's hydroelectric developments. 2 figs

  12. Photogeneration and recombination of charge carrier pairs and free charge carriers in polymer/fullerene bulk heterojunction films

    Energy Technology Data Exchange (ETDEWEB)

    Sliauzys, Gytis; Gulbinas, Vidmantas [Center for Physical Sciences and Technology, Savanoriu av. 231, 02300 Vilnius (Lithuania); Arlauskas, Kestutis [Department of Solid State Electronics, Vilnius University, Sauletekio al. 9, Build. 3, 10222 Vilnius (Lithuania)

    2012-07-15

    Photo-generation and recombination of free charge carriers in poly-3 (hexylthiophene) (P3HT) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM) blend films has been studied at different PCBM concentrations by means of fluorescence spectroscopy and transient photocurrent methods. We show that more than 80% of excitons form charge transfer (CT) states at PCBM concentrations above 4%. Efficiency of the CT state dissociation into free charge carries strongly depends on the PCBM concentration; the dissociation efficiency increases more than 30 times when PCBM concentration increases from 1 to 32%. We attribute the strong concentration dependence to formation of PCBM clusters facilitating electron migration and/or delocalization. Reduced charge carrier recombination coefficient has also been observed at high PCBM concentrations. We suggest that this may be partly caused by the reduced stability of reformed Coulombicaly bound charge pairs. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Compensating Differentials for Sexual Harassment

    OpenAIRE

    Joni Hersch

    2011-01-01

    Workplace sexual harassment is illegal, but many workers report that they have been sexually harassed. Exposure to the risk of sexual harassment may decrease productivity, which would reduce wages. Alternatively, workers may receive a compensating differential for exposure to sexual harassment, which would increase wages. Data on claims of sexual harassment filed with the Equal Employment Opportunity Commission are used to calculate the first measures of sexual harassment risks by industry, a...

  14. Bank Efficiency and Executive Compensation

    OpenAIRE

    Timothy King; Jonathan Williams

    2013-01-01

    We investigate whether handsomely rewarding bank executives’ realizes superior efficiency by determining if executive remuneration contracts produce incentives that offset potential agency problems and lead to improvements in bank efficiency. We calculate executive Delta and Vega to proxy executives’ risk-taking following changes in their compensation contracts and estimate their relationship with alternative profit efficiency. Our study uses novel instruments to account for the potentially e...

  15. Circadian Pacemaker – Temperature Compensation

    OpenAIRE

    Gerkema, Menno P.; Binder, Marc D.; Hirokawa, Nobutaka; Windhorst, Uwe

    2009-01-01

    One of the defining characteristics of circadian pacemakers and indicates the independence of the speed of circadian clock processes of environmental temperature. Mechanisms involved, so far not elucidated in full detail, entail at least two processes that are similarly affected by temperature changes, but with an opposing and counterbalancing effect on the periodicity of the clock system. As a result of temperature compensation, the increase in reaction velocity for every 10° rise in tempera...

  16. Has compensation become more flexible?

    OpenAIRE

    Sandra A. Cannon; Bruce C. Fallick; Michael Lettau; Raven E. Saks

    2000-01-01

    In recent years, numerous observers have argued that global competition, increased reliance on contingent workers, and the breakdown of implicit contracts have made compensation practices in the United States more flexible; in particular, employers have become more concerned with how an employee's pay compares to that in other firms and less concerned with considerations of equity or relative pay within the firm. This paper uses establishment-level data from the Bureau of Labor Statistics' Em...

  17. 38 CFR 21.3023 - Nonduplication; pension, compensation, and dependency and indemnity compensation.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Nonduplication; pension, compensation, and dependency and indemnity compensation. 21.3023 Section 21.3023 Pensions, Bonuses, and... Nonduplication; pension, compensation, and dependency and indemnity compensation. (a) Child; age 18. A child...

  18. Compensation Techniques in Accelerator Physics

    Energy Technology Data Exchange (ETDEWEB)

    Sayed, Hisham Kamal [Old Dominion Univ., Norfolk, VA (United States)

    2011-05-01

    Accelerator physics is one of the most diverse multidisciplinary fields of physics, wherein the dynamics of particle beams is studied. It takes more than the understanding of basic electromagnetic interactions to be able to predict the beam dynamics, and to be able to develop new techniques to produce, maintain, and deliver high quality beams for different applications. In this work, some basic theory regarding particle beam dynamics in accelerators will be presented. This basic theory, along with applying state of the art techniques in beam dynamics will be used in this dissertation to study and solve accelerator physics problems. Two problems involving compensation are studied in the context of the MEIC (Medium Energy Electron Ion Collider) project at Jefferson Laboratory. Several chromaticity (the energy dependence of the particle tune) compensation methods are evaluated numerically and deployed in a figure eight ring designed for the electrons in the collider. Furthermore, transverse coupling optics have been developed to compensate the coupling introduced by the spin rotators in the MEIC electron ring design.

  19. Motor carrier evaluation program plan

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) Transportation Management Program (TMP) has established a program to assist the DOE field offices and their contractors in evaluating the motor carriers used to transport DOE-owned hazardous and radioactive materials. This program was initiated to provide the DOE field offices with the tools necessary to help ensure, during this period of motor carrier deregulation, that only highly qualified carriers transport radioactive and hazardous commodities for the DOE. This program will assist DOE in maintaining their excellent performance record in the safe transportation of hazardous commodities. The program was also developed in response to public concern surrounding the transportation of hazardous materials. Representatives of other federal agencies, states, and tribal governments, as well as the news media, have expressed concern about the selection and qualification of carriers engaged in the transportation of Highway Route-Controlled Quantities (HRCQ) and Truckload (TL) quantities of radioactive material for the DOE. 8 refs

  20. Content Distribution for Telecom Carriers

    Directory of Open Access Journals (Sweden)

    Ben Falchuk

    2006-08-01

    Full Text Available Distribution of digital content is a key revenue opportunity for telecommunications carriers. As media content moves from analog and physical media-based distribution to digital on-line distribution, a great opportunity exists for carriers to claim their role in the media value chain and grow revenue by enhancing their broadband “all you can eat” high speed Internet access offer to incorporate delivery of a variety of paid content. By offering a distributed peer to peer content delivery capability with authentication, personalization and payment functions, carriers can gain a larger portion of the revenue paid for content both within and beyond their traditional service domains. This paper describes an approach to digital content distribution that leverages existing Intelligent Network infrastructure that many carriers already possess, as well as Web Services.

  1. Optically controlled SiCGe/SiC heterojunction transistor with charge-compensation layer

    Institute of Scientific and Technical Information of China (English)

    Pu Hong-Bin; Cao Lin; Chen Zhi-Ming; Ren Jie

    2011-01-01

    A novel optically controlled SiCGe/SiC heterojunction transistor with charge-compensation technique has been simulated by using commercial simulator. This paper discusses the electric field distribution, spectral response and transient response of the device. Due to utilizing p-SiCGe charge-compensation layer, the responsivity increases nearly two times and breakdown voltage increases 33%. The switching characteristic illustrates that the device is latch-free and its fall time is much longer than the rise time. With an increase of the light power density and wavelength, the rise time and fall time will become shorter and longer, respectively. In terms of carrier lifetime, a compromise should be made between the responsivity and switching speed, the ratio of them reaches maximum value when the minority carrier lifetime equals 90 ns.

  2. Sustainable bioenergy carriers from wastes

    OpenAIRE

    Pereira, M.A.; Cavaleiro, A. J.; Abreu, A. A.; Costa, J.C.; Sousa, D. Z.; Alves, M.M.

    2012-01-01

    The development of new technologies for renewable energy production is crucial for decreasing the reliance in fossil fuels and improving global sustainability. Waste materials are valuable resources that can be used for the production of energy carriers. Organic wastes can be anaerobically digested to ultimately produce methane. Hydrogen can be recovered from this process, if methanogenesis is inhibited. These energy carriers can also be derived from recalcitrant materials in a two step-proce...

  3. Single Line-to-Ground Fault Detection in Face of Cable Proliferation in Compensated Systems

    OpenAIRE

    Huang, Wan-Ying; Kaczmarek, Robert; Vannier, Jean-Claude

    2010-01-01

    We think that strong capacitive currents, generating unfavorable conditions for traditional protection relays in compensated systems, can be exploited as carriers of relevant information. Whenever extremely rapid information is required, we can find it when treating the discharging currents as useful for treatment, at a price of higher sampling frequency. After fault inception we dispose of several tens of microseconds to get the data in wave propagation area. This can make sense in simple di...

  4. Investigating thermal donors in n-type Cz silicon with carrier density imaging

    Directory of Open Access Journals (Sweden)

    Yu Hu

    2012-09-01

    Full Text Available A new method to map the thermal donor concentration in silicon wafers using carrier density imaging is presented. A map of the thermal donor concentration is extracted with high resolution from free carrier density images of a silicon wafer before and after growth of thermal donors. For comparison, free carrier density mapping is also performed using the resistivity method together with linear interpolation. Both methods reveal the same distribution of thermal donors indicating that the carrier density imaging technique can be used to map thermal donor concentration. The interstitial oxygen concentration can also be extracted using the new method in combination with Wijaranakula's model. As part of this work, the lifetime at medium injection level is correlated to the concentration of thermal donors in the as-grown silicon wafer. The recombination rate is found to depend strongly on the thermal donor concentration except in the P-band region.

  5. Respiratory load compensation in uremia.

    Science.gov (United States)

    Heinzmann, H G; Kassabian, J; Naqui, M N; Lavietes, M H

    1981-01-01

    The clinical significance of respiratory-system load-compensation is unknown. We have measured the responses to random presentation of single, elastic inspiratory loads in 36 subjects: 8 normal personnel (N), 9 with obesity (O), 10 with chronic renal failure under hemodialysis (H), 5 with pneumonia (P), and 4 with interstitial lung disease (CILD). We have expressed these responses as: (1) the ratio of elastance (or rigidity) of the system during loaded breathing to the elastance without loading (E'RS/ERS); (2) the ratio of tidal volume (VT) achieved when breathing from an inspiratory load to the VT predicted in the absence of load compensation (VTL/VTP); (3) the ratio of inspiratory flow rates during loaded and unloaded breaths; (4) the ratio of inspiratory time of loaded and unloaded breaths. We found E'RS/ERS in the O, H and P groups less than that of either CILD patients or N controls (F = 6.79; p less than 0.001). Passive elastance (ERS) although greater in groups O and H than in N (F = 3.88; p less than 0.025) did not account for the difference i E'RS in all groups. When expressed as VTL/VTP, the response to a 37-cm H2O/l load for groups H, O and P was less than that for N (F = 5.51; p less than 0.05). Diminished inspiratory time was observed in H, O and P patients when inspiring from this load. In contrast, inspiratory flow did not differ from that of normal subjects. Nerve conduction velocity was slightly reduced or normal in the H patients. Respiratory load compensation is deficient in H, O and P patients. The mechanism, which does not involve peripheral neuropathy, is unclear. PMID:7244394

  6. Self-compensation in ZnO thin films: An insight from X-ray photoelectron spectroscopy, Raman spectroscopy and time-of-flight secondary ion mass spectroscopy analyses

    International Nuclear Information System (INIS)

    As-grown ZnO typically exhibits n-type conductivity and the difficulty of synthesizing p-type ZnO for the realization of ZnO-based optoelectronic devices is mainly due to the compensation effect of a large background n-type carrier concentration. The cause of this self-compensation effect has not been conclusively identified although oxygen vacancies, zinc interstitials and hydrogen have been suggested. In this work, typical n-type ZnO thin films were prepared by sputtering and investigated using X-ray photoelectron spectroscopy, Raman spectroscopy and time-of-flight secondary ion mass spectroscopy to gain an insight on the possible cause of the self-compensation effect. The analyses found that the native defect that most likely behaved as the donor was zinc interstitial but some contribution of n-type conductivity could also come from the electronegative carbonates or hydrogen carbonates incorporated in the ZnO thin films

  7. Driver Compensation: Impairment or Improvement?

    Science.gov (United States)

    Young, Richard A

    2015-12-01

    Strayer et al.'s conclusion that their "cognitive distraction scale" for auditory-vocal tasks indicates "significant impairments to driving" is not supported by their data. Additional analysis demonstrates that slower brake reaction times during auditory-vocal tasks were fully compensated for by longer following distances to the lead car. Naturalistic driving data demonstrate that cellular conversation decreases crash risk, the opposite of the article's assumption. Hence, the scale's internal and external validities for indicating driving impairment are highly questionable. PMID:26534851

  8. DC-Compensated Current Transformer.

    Science.gov (United States)

    Ripka, Pavel; Draxler, Karel; Styblíková, Renata

    2016-01-01

    Instrument current transformers (CTs) measure AC currents. The DC component in the measured current can saturate the transformer and cause gross error. We use fluxgate detection and digital feedback compensation of the DC flux to suppress the overall error to 0.15%. This concept can be used not only for high-end CTs with a nanocrystalline core, but it also works for low-cost CTs with FeSi cores. The method described here allows simultaneous measurements of the DC current component. PMID:26805830

  9. Motor Carrier Evaluation Program procedure

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) Transportation Management Division (DOE-TMD) has the overall responsibility to provide a well-managed transportation program for the safe, efficient, and economical transportation of DOE-owned material. In the performance of these duties, the DOE-TMD has established an exemplary safety record in the transportation of hazardous materials. The DOE recognizes that its responsibility for hazardous material does not end when the shipments leave the DOE sites. A special partnership is needed between the DOE, the DOE contractors, and the carriers chosen to transport hazardous materials. As in any partnership, it is critical that DOE know essential information about its partner in this joint venture. In fulfillment of its responsibility for the safe transportation of radioactive materials as well as other hazardous commodities and wastes routinely shipped from many DOE locations nationwide, the DOE-TMD has developed this policy for a motor carrier evaluation program. It is the intent of the DOE-TMD that this Motor Carrier Evaluation Program be implemented at all DOE locations to the fullest extent practicable. This program will assist in the evaluation of carriers transporting Highway Route Controlled Quantities (HRCQ) of radioactive material, because these shipments frequently are in the ''public eye.'' The program will also evaluate truckload (TL) quantity transporters of hazardous materials, including radioactive material and chemical wastes. The program has also recently been expanded to include motor carriers transporting less-than-truckload (LTL) quantities of these materials

  10. Development of carrier usage for the treatment of radioactive effluent

    International Nuclear Information System (INIS)

    Low level radioactive liquid wastes are produced in many nuclear applications. Their physico-chemical characteristics may very considerably. Chemical precipitation is a convenient treatment method for the liquid streams of high salinity or solid content containing different radionuclide types. Generally, the concentrations of nuclides in liquid wastes are extremely low. For example, 1000 Bq of 137Cs makes about 3·10-10 g of caesium. Therefore conventional precipitation cannot be applied since the solubility product value is not exceeded. The carriers which are capable to adsorb the nuclides are used to achieve the nuclide removal. Stable isotopes of the nuclide are usually added as the carriers but any reagent which has similar chemical specifications with the nuclide can also be used as the carrier. Precipitation of these non-radioactive carriers ion together with the radionuclide is called co-precipitation. The operational steps of the chemical precipitation process should be established and applied in a treatment facility. Thus, the most suitable carrier for a particular nuclide and its usage conditions are required to be determined. In this study, the carriers for removal of 137Cs and uranium, their accurate amounts and usage conditions to achieve highest decontamination factors (DF) have been investigated. Residual sludge volumes were evaluated for cementation purposes. The cement composite samples were prepared for each set of experiments and hardening times were measured. 9 refs, 9 figs

  11. Carrier sense data highway system

    Science.gov (United States)

    Frankel, Robert

    1984-02-14

    A data transmission system includes a transmission medium which has a certain propagation delay time over its length. A number of data stations are successively coupled to the transmission medium for communicating with one another. Each of the data stations includes a transmitter for originating signals, each signal beginning with a carrier of a duration which is at least the propagation delay time of the transmission medium. Each data station also includes a receiver which receives other signals from other data stations and inhibits operation of the transmitter at the same data station when a carrier of another signal is received.

  12. Pointing compensation system for spacecraft instruments

    Science.gov (United States)

    Plescia, Carl T. (Inventor); Gamble, Donald W. (Inventor)

    1987-01-01

    A closed loop system reduces pointing errors in one or more spacecraft instruments. Associated with each instrument is a electronics package (3) for commanding motion in that instrument and a pointing control system (5) for imparting motion in that instrument in response to a command (4) from the commanding package (3). Spacecraft motion compensation logic (25) compensates for instrument pointing errors caused by instrument-motion-induced spacecraft motion. Any finite number of instruments can be so compensated, by providing each pointing control system (5) and each commanding package (3), for the instruments desired to be compensated, with a link to the spacecraft motion compensation logic (25). The spacecraft motion compensation logic (25) is an electronic manifestation of the algebraic negative of a model of the dynamics of motion of the spacecraft. An example of a suitable model, and computer-simulated results, are presented.

  13. How to avoid deferred-compensation troubles.

    Science.gov (United States)

    Freeman, Todd I

    2005-06-01

    Executive compensation packages have long included stock options and deferred compensation plans in order to compete for talent. Last year, Congress passed a law in response to the Enron debacle, in which executives were perceived to be protecting their deferred compensation at the expense of employees, creditors, and investors. The new law is designed to protect companies and their shareholders from being raided by the very executives that guided the company to financial ruin. Physicians who are part owners of medical practices need to know about the changes in the law regarding deferred compensation and how to avoid costly tax penalties. This article discusses how the changes affect medical practices as well as steps physician-owned clinics can take to avoid the risk of penalty, such as freezing deferred compensation and creating a new deferred compensation plan. PMID:16050311

  14. Engineering Compensations in Web Service Environment

    DEFF Research Database (Denmark)

    Schäfer, Micahel; Dolog, Peter; Nejdl, Wolfgang

    2007-01-01

    Business to business integration has recently been performed by employing Web service environments. Moreover, such environments are being provided by major players on the technology markets. Those environments are based on open specifications for transaction coordination. When a failure in such an...... compensations based on forward recovery principles. We extend the existing Web service transaction coordination architecture and infrastructure in order to support flexible compensation operations. A contract-based approach is being used, which allows the specification of permitted compensations at runtime. We...... introduce the abstract service and adapter components which allow us to separate the compensation logic from the coordination logic. In this way, we can easily plug in or plug out different compensation strategies based on a specification language defined on top of basic compensation activities and complex...

  15. Vertical vibration analysis for elevator compensating sheave

    International Nuclear Information System (INIS)

    Most elevators applied to tall buildings include compensating ropes to satisfy the balanced rope tension between the car and the counter weight. The compensating ropes receive tension by the compensating sheave, which is installed at the bottom space of the elevator shaft. The compensating sheave is only suspended by the compensating ropes, therefore, the sheave can move vertically while the car is traveling. This paper shows the elevator dynamic model to evaluate the vertical motion of the compensating sheave. Especially, behavior in emergency cases, such as brake activation and buffer strike, was investigated to evaluate the maximum upward motion of the sheave. The simulation results were validated by experiments and the most influenced factor for the sheave vertical motion was clarified

  16. A New Interpretation of Compensate Effect

    CERN Document Server

    Shao, M X

    2000-01-01

    A new interpretation of compensate effect is presented. The Hawking effect in general space-time can be taken as a compensate effect of the scale transformation of coordinate time on the horizon in generalized tortoise coordinates transformation. It is proved that the Hawking temperature is the pure gauge of compensate field in tortoise coordinates. This interpretation does not refer to a zero-temperature space-time.

  17. Compensation consultants and CEO pay: UK evidence

    OpenAIRE

    Voulgaris, Georgios; Stathopoulos, Konstantinos; Walker, Martin

    2010-01-01

    International audience Manuscript type: Empirical Research Question/ Issue: This paper provides new evidence on the effect of compensation consultants on CEO pay. Research Findings/ Insights: We produce new evidence on the managerial power approach (MPA) to corporate governance by examining the influence of compensation consultants on CEO pay structures and the decision to hire a compensation consultant in the UK. We find evidence that is not consistent with the MPA. Contrary to the MPA pr...

  18. Compensation for earnings risk under worker heterogeneity

    OpenAIRE

    Berkhout, P.; Hartog, J.; Webbink, D.

    2006-01-01

    We use two large Dutch datasets to estimate the Risk Augmented Mincer equation and test for risk compensation in expected earnings. We replicate earlier findings of a positive premium for risk and a negative premium for skew and add confirmation of the key results if we control for individual ability. We find that immigrants have graduated in more risky educations but obtain identical risk compensation. Among recent graduates, women receive higher risk compensation than men, consistent with t...

  19. Securitization and Compensation in Financial Institutions

    OpenAIRE

    Inderst, Roman; Pfeil, Sebastian

    2010-01-01

    We analyze the interaction between financial institutions' internal compensation policy, the quality of loans, and their securitization decision. We also assess the case for requiring financial institutions to defer bonus pay so as to make incentives more commensurate with the longer-term risk of their transactions. While mandatory deferred compensation can improve the quality of loans, we also show when it has the opposite effect. We further analyze when mandatory deferred compensation can c...

  20. Loss Aversion, Stochastic Compensation, and Team Incentives

    OpenAIRE

    Kohei Daido; Takeshi Murooka

    2013-01-01

    We investigate moral-hazard problems with limited liability where agents have expectation-based reference-dependent preferences. We show that stochastic compensation for low performance can be optimal. Because of loss aversion, the agents have first-order risk aversion to wage uncertainty. This causes the agents to work harder when their low performance is stochastically compensated. We also examine team incentives for credibly employing such stochastic compensation. In an optimal contract, l...

  1. 75 FR 72863 - Motor Carrier Safety Advisory Committee Public Meeting

    Science.gov (United States)

    2010-11-26

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration, DOT. ACTION: Notice of Motor Carrier Safety Advisory Committee Meeting. SUMMARY: FMCSA announces that the Agency's Motor Carrier Safety Advisory Committee...

  2. 76 FR 12214 - Motor Carrier Safety Advisory Committee Public Meeting

    Science.gov (United States)

    2011-03-04

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration, DOT. ACTION: Notice: Announcement of Motor Carrier Safety Advisory Committee meeting; request for comment. SUMMARY: The Federal Motor Carrier Safety...

  3. 75 FR 50797 - Motor Carrier Safety Advisory Committee Public Meeting

    Science.gov (United States)

    2010-08-17

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION: Notice of Motor Carrier Safety Advisory Committee Meeting. SUMMARY: FMCSA announces that its Motor Carrier Safety Advisory Committee (MCSAC)...

  4. Enthalpy-entropy compensation in protein unfolding

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Enthalpy-entropy compensation was found to be a universal law in protein unfolding based on over 3 000 experimental data. Water molecular reorganization accompanying the protein unfolding was suggested as the origin of the enthalpy-entropy compensation in protein unfolding. It is indicated that the enthalpy-entropy compensation constitutes the physical foundation that satisfies the biological need of the small free energy changes in protein unfolding, without the sacrifice of the bio-diversity of proteins. The enthalpy-entropy compensation theory proposed herein also provides valuable insights into the Privalov's puzzle of enthalpy and entropy convergence in protein unfolding.

  5. Lithium compensation for full cell operation

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Jie; Zheng, Jianming; Chen, Xilin; Lu, Dongping; Liu, Jun; Jiguang, Jiguang

    2016-05-17

    Disclosed herein are embodiments of a lithium-ion battery system comprising an anode, an anode current collector, and a layer of lithium metal in contact with the current collector, but not in contact with the anode. The lithium compensation layer dissolves into the electrolyte to compensate for the loss of lithium ions during usage of the full cell. The specific placement of the lithium compensation layer, such that there is no direct physical contact between the lithium compensation layer and the anode, provides certain advantages.

  6. Dispersion compensation for attosecond electron pulses

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Peter; Baumgarten, Cory; Batelaan, Herman; Centurion, Martin [Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588 (United States)

    2012-08-20

    We propose a device to compensate for the dispersion of attosecond electron pulses. The device uses only static electric and magnetic fields and therefore does not require synchronization to the pulsed electron source. Analogous to the well-known optical dispersion compensator, an electron dispersion compensator separates paths by energy in space. Magnetic fields are used as the dispersing element, while a Wien filter is used for compensation of the electron arrival times. We analyze a device with a size of centimeters, which can be applied to ultrafast electron diffraction and microscopy, and fundamental studies.

  7. Polarization-based compensation of astigmatism

    Science.gov (United States)

    Chowdhury, Dola Roy; Bhattacharya, Kallol; Chakraborty, Ajay K.; Ghosh, Raja

    2004-02-01

    One approach to aberration compensation of an imaging system is to introduce a suitable phase mask at the aperture plane of an imaging system. We utilize this principle for the compensation of astigmatism. A suitable polarization mask used on the aperture plane together with a polarizer-retarder combination at the input of the imaging system provides the compensating polarization-induced phase steps at different quadrants of the apertures masked by different polarizers. The aberrant phase can be considerably compensated by the proper choice of a polarization mask and suitable selection of the polarization parameters involved. The results presented here bear out our theoretical expectation.

  8. Undulator with dynamic compensation of magnetic forces

    Energy Technology Data Exchange (ETDEWEB)

    Gluskin, Efim; Trakhtenberg, Emil; Xu, Joseph Z.

    2016-05-31

    A method and apparatus for implementing dynamic compensation of magnetic forces for undulators are provided. An undulator includes a respective set of magnet arrays, each attached to a strongback, and placed on horizontal slides and positioned parallel relative to each other with a predetermined gap. Magnetic forces are compensated by a set of compensation springs placed along the strongback. The compensation springs are conical springs having exponential-force characteristics that substantially match undulator magnetic forces independently of the predetermined gap. The conical springs are positioned along the length of the magnets.

  9. Studies on carrier free promethium-147

    International Nuclear Information System (INIS)

    The present investigation was intended to study the state of Pm-147 in solution and its adsorbed state on membrane filters by varying the concentrations of Pm-147 solution and its pH. Also, the study on the coprecipitation of Pm-147 with Fe(OH)3 was carried out by varying amounts of Fe(OH)3 and pH of the solution. The carrier-free Pm-147 exists in an ionic state of pm3+ in solution, and is adsorbed on membrane filter in filtration process. The adsorbed state of Pm-147 on the membrane filter shows various ionic state at a constant ionic strength of 0.1M NaCl, that is, Pm3+ state exists until pH value of 5.0, then gradually Pm(OH)2+ state appears between pH value of 5.0 to 6.0, and the state of Pm(OH)2+ and Pm(OH)3 would be expected at the higher pH value of 6.0. Coprecipitation of Pm-147 on Fe(OH)3 is an adsorption penomenon in an ionic state of Pm3+ in acidic condition. At higher pH and larger amount of Fe carrier, the adsorbed state of Pm-147 shows Pm(OH)2+ and Pm(OH)2+ state. As a results of the present studies, it is seen that the characteristic of carrier free radioisotopes is not due to the radioactivity, but due to the adsorption of ultramicroquantity of radioisotopes. Therefore, the knowledge on the ultramicroquantity of radioisotopes could help for the solution of decontamination in handing and chemical procedure with radioisotopes. (author)

  10. A study on the minority carrier diffusion length in n-type GaN films

    Institute of Scientific and Technical Information of China (English)

    DENG Dongmei; ZHAO Degang; WANG Jinyan; YANG Hui; WEN Cheng Paul

    2007-01-01

    The minority carrier diffusion length of n-type GaN films grown by metalorganic chemical vapor deposition (MOCVD) has been studied by measuring the surface photovoltaic (PV) spectra. It was found that the minority carrier diffusion length of undoped n-type GaN is considerably larger than that in lightly Si-doped GaN. However, the data suggested that the dislocation and electron concentration appear not to be responsible for the minority carrier diffusion length. It is suggested that Si doping plays an important role in decreasing the minority carrier diffusion length.

  11. Hot carrier degradation in semiconductor devices

    CERN Document Server

    2015-01-01

    This book provides readers with a variety of tools to address the challenges posed by hot carrier degradation, one of today’s most complicated reliability issues in semiconductor devices.  Coverage includes an explanation of carrier transport within devices and book-keeping of how they acquire energy (“become hot”), interaction of an ensemble of colder and hotter carriers with defect precursors, which eventually leads to the creation of a defect, and a description of how these defects interact with the device, degrading its performance. • Describes the intricacies of hot carrier degradation in modern semiconductor technologies; • Covers the entire hot carrier degradation phenomenon, including topics such as characterization, carrier transport, carrier-defect interaction, technological impact, circuit impact, etc.; • Enables detailed understanding of carrier transport, interaction of the carrier ensemble with the defect precursors, and an accurate assessment of how the newly created defects imp...

  12. Temperature-compensated induction extensometer

    International Nuclear Information System (INIS)

    A linear displacement transducer, or extensometer, has been designed and constructed to measure displacements over a range of 0--150 mm. The transducer works by electromagnetic induction and consists of a bifilar coil coaxial with two conducting cylinders, one inside and the other outside the coil. The induction extensometer has been designed to eliminate errors caused by temperature changes from 00 to 10000C. Experimental measurements show an error of 1 mm over the 150-mm displacement range for a temperature change of 5000C, and the error should not be larger over the full 10000C temperature range. The displacement range can be varied from 2.5 to 250 mm by scaling the entire experiment up or down, and the temperature compensation can be made for any temperature range that is compatible with the constructional materials

  13. SIS junction reactance complete compensation

    International Nuclear Information System (INIS)

    SIS junction geometrical capacitance together with out of phase current Ikk impedance component forms sufficient junction reactance XSIS = (ωC + BQ)-1. This paper suggests the way to resonate out both ωC and BQ by using additional identical SIS junction connected to the first through a long line impedance inverter and RF + DC biased symmetrically to the first. Pumped IV curves without quantum reactance and frequency impedance patterns of the system were calculated. Calculations demonstrated the presence of high and even negative induced dynamic resistance regions at high order quasiparticle steps for the case of SIS junction reactance complete compensation. The suggested method may be used in SIS mixers and detectors for a better RF matching

  14. Compensated takings and negotiated solutions

    International Nuclear Information System (INIS)

    More than 30 year ago, the USA began protecting its environment with regulatory laws. However, this approach has progressed to the point where our economic health may have needlessly incurred long-term damage. The article explores the implications of a resurgent demand for legal guarantees for compensation when environmental regulations take individual property. What will happen when a price tag is attached to new or existing environmental laws? Some predict dire results; however, a more balanced and efficient policy may lie ahead. The discussion explores the implications of recent rulings, describes possible outcomes, and offers several alternatives to the traditional lobby-and-appeal tactics used in setting environmental policy. The authors conclude that as the concept of a regulatory taking is restored, more innovative negotiated solutions will take place between competing interests as they are given more equal legal footing

  15. Compensation for incoherent ground motion

    International Nuclear Information System (INIS)

    The power spectrum density and coherence function for ground motions are studied for the construction of the next generation electron-positron linear collider. It should provide a center of mass energy between 500 GeV-1 TeV with luminosity as high as 1033 to 1034 cm-2 sec-1. Since the linear collider has a relatively slow repetition rate, large number of particles and small sizes of the beam should be generated and preserved in the machine to obtain the required high luminosity. One of the most critical parameters is the extremely small vertical beam size at the interaction point, thus a proper alignment system for the focusing and accelerating elements of the machine is necessary to achieve the luminosity. We describe recent observed incoherent ground motions and an alignment system to compensate the distortion by the ground motions. (authors)

  16. 38 CFR 3.351 - Special monthly dependency and indemnity compensation, death compensation, pension and spouse's...

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Special monthly dependency and indemnity compensation, death compensation, pension and spouse's compensation ratings. 3.351 Section 3.351 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION...

  17. 76 FR 49398 - Non-Discrimination in Compensation; Compensation Data Collection Tool

    Science.gov (United States)

    2011-08-10

    ... Compensation; Compensation Data Collection Tool AGENCY: Office of Federal Contract Compliance Programs. ACTION... on the development and implementation of a compensation data collection tool. Possible uses for the... from interested parties as early as possible in the development process of this new data...

  18. 75 FR 49595 - Performance of Functions; Claims for Compensation Under the Federal Employees' Compensation Act...

    Science.gov (United States)

    2010-08-13

    ... any comments by mail early. Comments on the proposed rule will be available for public inspection... regarding types and manner of transport allowed. Directed Medical Examinations Section 10.320 has been...; Claims for Compensation Under the Federal Employees' Compensation Act; Compensation for Disability...

  19. Advanced and flexible multi-carrier receiver architecture for high-count multi-core fiber based space division multiplexed applications

    OpenAIRE

    Rameez Asif

    2016-01-01

    Space division multiplexing (SDM), incorporating multi-core fibers (MCFs), has been demonstrated for effectively maximizing the data capacity in an impending capacity crunch. To achieve high spectral-density through multi-carrier encoding while simultaneously maintaining transmission reach, benefits from inter-core crosstalk (XT) and non-linear compensation must be utilized. In this report, we propose a proof-of-concept unified receiver architecture that jointly compensates optical Kerr effec...

  20. Multiple Compensation Consultants and CEO Pay

    NARCIS (Netherlands)

    Kabir, Rezaul; Minhat, Marizah

    2010-01-01

    The study examines the practice of employing multiple compensation consultants. Data for a sample of UK companies over the period 2003-2006 are analyzed using a variety of econometric methods. We find that CEOs receive higher equity-based pay when firms employ more than one compensation consultant.

  1. Tilt/Integral/Derivative Compensators For Controllers

    Science.gov (United States)

    Lurie, Boris J.

    1995-01-01

    Tilt/integral/derivative (TID) compensators for tunable feedback control systems offer advantages over proportional/integral/derivative compensators. Designed and adjusted more easily, and made to reject disturbances more strongly and less sensitive to variations in parameters of controlled system.

  2. Analytic compensation methods in dynamic tomography

    International Nuclear Information System (INIS)

    Recent progresses in X-ray tomography allow to study some organs dynamically. The aim of this work is to analyze the deformation compensation algorithms used to integrate dynamical evolution models into the image reconstruction processes. An exact and efficient analytical method of movement compensation is presented and applied to simulated data. Abstract only. (J.S.)

  3. A brief history of dosage compensation

    Indian Academy of Sciences (India)

    Stanley M. Gartler

    2014-08-01

    In 1914, H. J. Muller postulated the origin of the Y chromosome as having resulted from restricted recombination between homologous sex chromosomes in the male and the accumulation of deleterious mutations. This evolutionary process leads to dosage compensation. This article lays out a brief history of dosage compensation in genetics.

  4. Options in Compensation: Promises and Pitfalls

    DEFF Research Database (Denmark)

    Flor, Christian Riis; Frimor, Hans; Munk, Claus

    2014-01-01

    We derive the optimal compensation contract in a principal–agent setting in which outcome is used to provide incentives for both effort and risky investments. To motivate investment, optimal compensation entails rewards for high as well as low outcomes, and it is increasing at the mean outcome to...

  5. Reinventing Teacher Compensation Systems. CPRE Finance Briefs.

    Science.gov (United States)

    Kelley, Carolyn; Odden, Allan

    Other organizations in the United States have successfully implemented new compensation structures. This publication argues that it is time for education to join these successful efforts and revise teacher-pay systems. The brief provides a short history of changes in teacher compensation over the last century and a discussion of key organizational…

  6. Motion compensator for holographic motion picture camera

    Science.gov (United States)

    Kurtz, R. L.

    1973-01-01

    When reference beam strikes target it undergoes Doppler shift dependent upon target velocity. To compensate, object beam is first reflected from rotating cylinder that revolves in direction opposite to target but at same speed. When beam strikes target it is returned to original frequency and is in phase with reference beam. Alternatively this motion compensator may act on reference beam.

  7. Inhomogeneous and nonstationary Hall states of the CDW with quantized normal carriers

    OpenAIRE

    Brazovskii, Serguei

    2015-01-01

    We suggest a theory for a deformable and sliding charge density wave (CDW) in the Hall bar geometry for the quantum limit when the carriers in remnant small pockets are concentrated at lowest Landau levels (LL) forming a fractionally ($\

  8. Gravitational compensation for the LISA pathfinder

    International Nuclear Information System (INIS)

    This paper addresses the problem of compensating self-gravity for the LISA Technology Package. Massive components onboard the spacecraft produce a gravitational imbalance on the free-falling test masses. We present here a compensation scheme to reduce the gravitational forces, torques, stiffness and cross-talk to values within requirements. Gravitational analysis and subsequent compensation are needed to limit the gravitational imbalances in order to reduce the force noise and force gradients associated with the electrostatic actuation that must compensate any residual gravitational imbalances. Starting from an educated guess based on simple Newtonian arguments, we present the approximate shapes of a compensation block solution which minimizes the residual gravitational imbalance and stiffness while adding a minimum of mass

  9. Gravitational compensation for the LISA pathfinder

    Energy Technology Data Exchange (ETDEWEB)

    Armano, M [Dipartimento di Fisica, Universita di Trento and INFN, Sezione di Padova, Gruppo Collegato di Trento, I-38050, Povo, Trento (Italy); Dipartimento di Fisica, Universita degli Studi dell' Insubria, via Valleggio, 11, 22100 Como (Italy); Bortoluzzi, D [Dipartimento di Ingegneria Meccanica Strutturale, Universita di Trento, Mesiano, Trento (Italy); Hoyle, C D [Dipartimento di Fisica, Universita di Trento and INFN, Sezione di Padova, Gruppo Collegato di Trento, I-38050, Povo, Trento (Italy); Vitale, S [Dipartimento di Fisica, Universita di Trento and INFN, Sezione di Padova, Gruppo Collegato di Trento, I-38050, Povo, Trento (Italy)

    2005-05-21

    This paper addresses the problem of compensating self-gravity for the LISA Technology Package. Massive components onboard the spacecraft produce a gravitational imbalance on the free-falling test masses. We present here a compensation scheme to reduce the gravitational forces, torques, stiffness and cross-talk to values within requirements. Gravitational analysis and subsequent compensation are needed to limit the gravitational imbalances in order to reduce the force noise and force gradients associated with the electrostatic actuation that must compensate any residual gravitational imbalances. Starting from an educated guess based on simple Newtonian arguments, we present the approximate shapes of a compensation block solution which minimizes the residual gravitational imbalance and stiffness while adding a minimum of mass.

  10. Rectangular Laser Resonators with Astigmatic Compensation

    DEFF Research Database (Denmark)

    Skettrup, Torben

    2005-01-01

    An investigation of rectangular resonators with a view to the compensation of astigmatism has been performed. In order to have beam waists placed at the same positions in the tangential and sagittal planes, pairs of equal mirrors were considered. It was found that at least two concave mirrors are...... necessary to obtain compensation. Four-concave-mirror systems are most stable close to the quadratic geometry, although the symmetric quadratic resonator itself cannot be compensated for astigmatism. Using four equal concave mirrors, compensation of astigmatism can be obtained in two arms at the same time....... Usually several stability ranges are found for four-mirror resonators with pair-wise equal mirrors, and it is possible with these systems to obtain small compensated beam waist radii suitable for frequency conversion. Relevant formulae are given and several relevant examples are shown using simulation...

  11. RESEALED ERYTHROCYTES AS A POTENTIAL DRUG CARRIER SYSTEM

    Directory of Open Access Journals (Sweden)

    Reena Gill

    2012-02-01

    Full Text Available Novel drug delivery system has been introduced to overwhelm the drawback of fluctuating drug levels associated with conventional dosage forms. Out of various cellular carrier systems, erythrocytes (red blood cells, RBC have been the most widely investigated and found to possess great potential for the delivery of drugs and drug-loaded microspheres. These cellular carriers, having remarkable biocompatibility, biodegradability, and life-span in circulation, can be loaded by a wide spectrum of compounds of therapeutic value using different chemically, as well as physically, based methods. Most of the characteristics of the erythrocytes, including shape, membrane fragility, deformability, and hematologic indices undergo some degree of irreversible changes during the loading procedure. Carrier erythrocytes are prepared simply by collecting blood sample from the organism of interest, separating erythrocytes from plasma, then by using various physical and chemical methods the cells are broken. The drug is entrapped into the erythrocytes and finally resealing the resultant cellular carriers. Hence these carriers are suitably known as Resealed erythrocytes. Surface modification with glutaraldehyde, antibodies, carbohydrates like sialic acid and biotinylation of loaded erythrocytes (biotinylated erythrocytes is possible to achieve various levels of targeting and increased circulation half-life. Upon reinjection the drug loaded erythrocytes serve as slow circulation depots, targets the drug to the reticuloendothelial system (RES, prevents degradation of loaded drug by endogenous chemicals, attain steady state concentration of drug and decrease the toxic-effects of loaded drug.

  12. The determinants of full-service carriers airfares in European hub-to-hub markets

    OpenAIRE

    Zhang, Shengrun; Derudder, Ben; Witlox, Frank

    2014-01-01

    This paper explores the factors influencing the pricing behaviour of full-service carriers in European hub-to-hub markets. Drawing on a 2009 dataset containing route and airfare information, we establish an econometric model to estimate the impact of route structure, alliances, and market concentration on the pricing of European full-service carriers in these markets. The results suggest that alliances on routes connecting two primary hubs, airport concentration, market share inequality and c...

  13. Extraction and Transport of Amino Acids Using Kryptofix 5 as Carrier through Liquid Membrane

    OpenAIRE

    Pankaj Raizada; Uma Sharma

    2013-01-01

    The present work explores membrane-mediated extraction and transport studies of amino acids through artificial bulk liquid membrane system with kryptofix 5 as a carrier. The various reaction parameters such as amino acid concentration, carrier concentration, time, pH, and stirring effect were studied to optimize reaction conditions. The stirring of source and receiving phases increased the efficiency of extraction process. Noncyclic receptor kryptofix 5 with five oxyethylene units an...

  14. Influência da temperatura do ar de secagem e da concentração de agente carreador sobre as propriedades físico-químicas do suco de açaí em pó Influence of drying air temperature and carrier agent concentration on the physicochemical properties of açai juice powder

    Directory of Open Access Journals (Sweden)

    Renata Valeriano Tonon

    2009-06-01

    Full Text Available A influência da temperatura do ar de secagem e da concentração de agente carreador sobre as propriedades físico-químicas do suco de açaí em pó produzido por spray drying foi avaliada. O processo foi realizado em um mini spray dryer de bancada e maltodextrina 10DE foi utilizada como agente carreador. A temperatura do ar de secagem variou de 138 a 202 °C e a concentração de maltodextrina variou de 10 a 30%. As características analisadas foram: umidade, higroscopicidade, retenção de antocianinas, cor, distribuição do tamanho de partículas e morfologia. O aumento da temperatura resultou em partículas maiores, menos úmidas, mais higroscópicas e com menor retenção de antocianinas, além de provocar uma diminuição do parâmetro de cor L* e do ângulo de tom H*. O aumento na concentração de maltodextrina resultou em partículas maiores e menos higroscópicas, com maior luminosidade (L*, menores valores de C* e maiores valores de H*. Em relação à morfologia, o aumento da temperatura levou à formação de uma maior quantidade de partículas com superfície lisa, fato atribuído à maior transferência de calor e, consequentemente, à formação mais rápida de uma membrana ao redor da gota atomizada.The objective of this work was to study the influence of inlet air temperature and maltodextrin concentration on the physicochemical properties of açai juice powder produced by spray drying. The process was carried out in a mini spray dryer and the maltodextrin 10DE was used as carrier agent. Inlet air temperature varied from 138 to 202 °C and maltodextrin concentration varied from 10 to 30%. The characteristics analyzed were: moisture content, hygroscopicity, anthocyanin retention, color, particle size distribution, and morphology. The increase in the temperature resulted in particles with larger size, less moisture content, more hygroscopy and with lower anthocyanin retention, besides promoting a reduction in the color

  15. Carrier Deformability in Drug Delivery.

    Science.gov (United States)

    Morilla, Maria Jose; Romero, Eder Lilia

    2016-01-01

    Deformability is a key property of drug carriers used to increase the mass penetration across the skin without disrupting the lipid barrier. Highly deformable vesicles proved to be more effective than conventional liposomes in delivering drugs into and across the mammalian skin upon topical non occlusive application. In the past five years, highly deformable vesicles have been used for local delivery of drugs on joint diseases, skin cancer, atopic dermatitis, would healing, psoriasis, scar treatment, fungal, bacteria and protozoa infections. Promising topical vaccination strategies rely also in this type of carriers. Here we provide an overview on the main structural and mechanical features of deformable vesicles, to finish with an extensive update on their latest preclinical applications. PMID:26675226

  16. Fatigue reliability for LNG carrier

    Institute of Scientific and Technical Information of China (English)

    Xiao Taoyun; Zhang Qin; Jin Wulei; Xu Shuai

    2011-01-01

    The procedure of reliability-based fatigue analysis of liquefied natural gas (LNG) carrier of membrane type under wave loads is presented. The stress responses of the hotspots in regular waves with different wave heading angles and wave lengths are evaluated by global ship finite element method (FEM). Based on the probabilistic distribution function of hotspots' short-term stress-range using spectral-based analysis, Weibull distribution is adopted and discussed for fitting the long-term probabilistic distribution of stress-range. Based on linear cumulative damage theory, fatigue damage is characterized by an S-N relationship, and limit state function is established. Structural fatigue damage behavior of several typical hotspots of LNG middle ship section is clarified and reliability analysis is performed. It is believed that the presented results and conclusions can be of use in calibration for practical design and initial fatigue safety evaluation for membrane type LNG carrier.

  17. Gemini surfactants as gene carriers

    Directory of Open Access Journals (Sweden)

    Teresa Piskorska

    2010-03-01

    Full Text Available Gemini surfactants are a new class of amphiphilic compounds built from two classic surfactant moieties bound together by a special spacer group. These compounds appear to be excellent for creating complexes with DNA and are effective in mediating transfection. Thanks to their construction, DNA carrier molecules built from gemini surfactants are able to deliver genes to cells of almost any DNA molecule size, unattainable when using viral gene delivery systems. Moreover, they are much safer for living organisms.

  18. Recursive SDN for Carrier Networks

    OpenAIRE

    McCauley, James; Liu, Zhi; Panda, Aurojit; Koponen, Teemu; Raghavan, Barath; Rexford, Jennifer; Shenker, Scott

    2016-01-01

    Control planes for global carrier networks should be programmable (so that new functionality can be easily introduced) and scalable (so they can handle the numerical scale and geographic scope of these networks). Neither traditional control planes nor new SDN-based control planes meet both of these goals. In this paper, we propose a framework for recursive routing computations that combines the best of SDN (programmability) and traditional networks (scalability through hierarchy) to achieve t...

  19. Biocheese: A Food Probiotic Carrier

    OpenAIRE

    J. M. Castro; M. E. Tornadijo; Fresno, J. M.; H. Sandoval

    2015-01-01

    This review describes some aspects related to the technological barriers encountered in the development and stability of probiotic cheeses. Aspects concerning the viability of probiotic cultures in this matrix are discussed and the potential of cheese as a biofunctional food carrier is analyzed, outlying some points related to health and safety. In general, the manufacture of probiotic cheese should have little change when compared with the elaboration of cheese in the traditional way. The ph...

  20. Preventative maintenance of straddle carriers

    Directory of Open Access Journals (Sweden)

    Si Li

    2015-02-01

    Full Text Available Background: Robotic vehicles such as straddle carriers represent a popular form of cargo handling amongst container terminal operators.Objectives: The purpose of this industry-driven study is to model preventative maintenance (PM influences on the operational effectiveness of straddle carriers.Method: The study employs historical data consisting of 21 273 work orders covering a 27-month period. Two models are developed, both of which forecast influences of PM regimes for different types of carrier.Results: The findings of the study suggest that the reliability of the straddle fleet decreases with increased intervals of PM services. The study also finds that three factors – namely resources, number of new straddles, and the number of new lifting work centres – influence the performances of straddles.Conclusion: The authors argue that this collaborative research exercise makes a significant contribution to existing supply chain management literature, particularly in the area of operations efficiency. The study also serves as an avenue to enhance relevant management practice.

  1. Charge compensation in extremely large magnetoresistance materials LaSb and LaBi revealed by first-principles calculations

    Science.gov (United States)

    Guo, Peng-Jie; Yang, Huan-Cheng; Zhang, Bing-Jing; Liu, Kai; Lu, Zhong-Yi

    2016-06-01

    By the first-principles electronic structure calculations, we have systematically studied the electronic structures of recently discovered extremely large magnetoresistance (XMR) materials LaSb and LaBi. We find that both LaSb and LaBi are semimetals with the electron and hole carriers in balance. The calculated carrier densities on the order of 1020cm-3 are in good agreement with the experimental values, implying long mean-free time of carriers at low temperatures and thus high carrier mobilities. With a semiclassical two-band model, the charge compensation and high carrier mobilities naturally explain: (i) the XMR observed in LaSb and LaBi, (ii) the nonsaturating quadratic dependence of XMR on an external magnetic field, and (iii) the resistivity plateau in the turn-on temperature behavior at very low temperatures. The explanation of these features without resorting to the topological effect indicates that they should be the common characteristics of all electron-hole compensated semimetals.

  2. Ga co-doping in Cz-grown silicon ingots to overcome limitations of B and P compensated silicon feedstock for PV applications

    Energy Technology Data Exchange (ETDEWEB)

    Forster, Maxime [APOLLON SOLAR, 66 cours Charlemagne, 69002 Lyon (France); INSA de LYON, INL, 7 av. J. Capelle, 69621 Villeurbanne Cedex (France); Fourmond, Erwann; Lemiti, Mustapha [INSA de LYON, INL, 7 av. J. Capelle, 69621 Villeurbanne Cedex (France); Einhaus, Roland; Lauvray, Hubert; Kraiem, Jed [APOLLON SOLAR, 66 cours Charlemagne, 69002 Lyon (France)

    2011-03-15

    In this paper, we investigate gallium co-doping during CZ crystallization of boron and phosphorus compensated Si. It is shown that the addition of gallium yields a fully p-type ingot with high resistivity despite high B and P contents in the silicon. Segregation of doping impurities is consistent with theory. Minority carrier lifetime and majority carrier mobility measurements indicate that this material is suitable for the realization of solar cells with comparable efficiencies to standard material. Significant light-induced degradation of minority carrier lifetime is however revealed to occur in this material. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  3. Responsible implementation of expanded carrier screening.

    Science.gov (United States)

    Henneman, Lidewij; Borry, Pascal; Chokoshvili, Davit; Cornel, Martina C; van El, Carla G; Forzano, Francesca; Hall, Alison; Howard, Heidi C; Janssens, Sandra; Kayserili, Hülya; Lakeman, Phillis; Lucassen, Anneke; Metcalfe, Sylvia A; Vidmar, Lovro; de Wert, Guido; Dondorp, Wybo J; Peterlin, Borut

    2016-06-01

    This document of the European Society of Human Genetics contains recommendations regarding responsible implementation of expanded carrier screening. Carrier screening is defined here as the detection of carrier status of recessive diseases in couples or persons who do not have an a priori increased risk of being a carrier based on their or their partners' personal or family history. Expanded carrier screening offers carrier screening for multiple autosomal and X-linked recessive disorders, facilitated by new genetic testing technologies, and allows testing of individuals regardless of ancestry or geographic origin. Carrier screening aims to identify couples who have an increased risk of having an affected child in order to facilitate informed reproductive decision making. In previous decades, carrier screening was typically performed for one or few relatively common recessive disorders associated with significant morbidity, reduced life-expectancy and often because of a considerable higher carrier frequency in a specific population for certain diseases. New genetic testing technologies enable the expansion of screening to multiple conditions, genes or sequence variants. Expanded carrier screening panels that have been introduced to date have been advertised and offered to health care professionals and the public on a commercial basis. This document discusses the challenges that expanded carrier screening might pose in the context of the lessons learnt from decades of population-based carrier screening and in the context of existing screening criteria. It aims to contribute to the public and professional discussion and to arrive at better clinical and laboratory practice guidelines. PMID:26980105

  4. GVD compensation schemes with considering PMD

    Institute of Scientific and Technical Information of China (English)

    Aiying Yang(杨爱英); Anshi Xu(徐安士); Deming Wu(吴德明)

    2003-01-01

    Three group velocity dispersion (GVD) compensation schemes, i.e., the post-compensation, pre-compensation and hybrid-compensation schemes, are discussed with considering polarization mode disper-sion (PMD). In the 10- and 40-Gbit/s non-return-zero (NRZ) on-off-key (OOK) systems, three physicalfactors, Kerr effect, GVD and PMD are considered. The numerical results show that, when the impactof PMD is taken into account, the GVD pre-compensation scheme performs best with more than 1 dBbetter of average eye-opening penalty (EOP) when input power is up to 10 dBm in the 10-Gbit/s system.However the GVD post-compensation scheme perforns best for the case of 40 Gbit/s with input power lessthan 13 dBm, and GVD pre-compensation will be better if the input power increased beyond this range.The results are different from those already reported under the assumption that the impact of PMD isneglected. Therefore, the research in this paper provide a different insight into the system optimizationwhen PMD, Kerr effect and GVD are considered.

  5. Effects of a carrier and its diluent on the transport of metals across supported liquid membranes (SLM). I. Solubility mechanism

    International Nuclear Information System (INIS)

    A new phenomenon called the solubility mechanism was observed experimentally and explained theoretically. This phenomenon helps explain the monotonic behavior of the flux with respect to the carrier concentration through the use of a simplified model. The reason why the linear behavior of the flux-carrier relationship was observed by past theories is because they ignore a process which occurs simultaneously with the carrier-metal reaction. The authors believe that this process is the solubility process in which the metal distribution within the organic phase is a function of both carrier and diluent concentrations

  6. 49 CFR 376.22 - Exemption for private carrier leasing and leasing between authorized carriers.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Exemption for private carrier leasing and leasing... MOTOR CARRIER SAFETY REGULATIONS LEASE AND INTERCHANGE OF VEHICLES Exemptions for the Leasing Regulations § 376.22 Exemption for private carrier leasing and leasing between authorized carriers....

  7. Compensator configurations for load currents' symmetrization

    Science.gov (United States)

    Rusinaru, D.; Manescu, L. G.; Dinu, R. C.

    2016-02-01

    This paper approaches aspects regarding the mitigation effects of asymmetries in 3-phase 3-wire networks. The measure consisting in connecting of load current symmetrization devices at the load coupling point is presented. A time-variation of compensators parameters is determined as a function of the time-recorded electrical values. The general sizing principle of the load current symmetrization reactive components is based on a simple equivalent model of the unbalanced 3-phase loads. By using these compensators a certain control of the power components transits is ensured in the network. The control is based on the variations laws of the compensators parameters as functions of the recorded electrical values: [B] = [T]·[M]. The link between compensator parameters and measured values is ensured by a transformation matrix [T] for each operation conditions of the supply network. Additional conditions for improving of energy and efficiency performance of the compensator are considered: i.e. reactive power compensation. The compensator sizing algorithm was implemented into a MATLAB environment software, which generate the time-evolution of the parameters of load current symmetrization device. The input data of application takes into account time-recording of the electrical values. By using the compensator sizing software, some results were achieved for the case of a consumer connected at 20 kV busbar of a distribution substation, during 24 hours measurement session. Even the sizing of the compensators aimed some additional network operation aspects (power factor correction) correlated with the total or major load symmetrizations, the harmonics aspects of the network values were neglected.

  8. Compressed sensing techniques for receiver based post-compensation of transmitter's nonlinear distortions in OFDM systems

    KAUST Repository

    Owodunni, Damilola S.

    2014-04-01

    In this paper, compressed sensing techniques are proposed to linearize commercial power amplifiers driven by orthogonal frequency division multiplexing signals. The nonlinear distortion is considered as a sparse phenomenon in the time-domain, and three compressed sensing based algorithms are presented to estimate and compensate for these distortions at the receiver using a few and, at times, even no frequency-domain free carriers (i.e. pilot carriers). The first technique is a conventional compressed sensing approach, while the second incorporates a priori information about the distortions to enhance the estimation. Finally, the third technique involves an iterative data-aided algorithm that does not require any pilot carriers and hence allows the system to work at maximum bandwidth efficiency. The performances of all the proposed techniques are evaluated on a commercial power amplifier and compared. The error vector magnitude and symbol error rate results show the ability of compressed sensing to compensate for the amplifier\\'s nonlinear distortions. © 2013 Elsevier B.V.

  9. 41 CFR 301-10.116 - What must I do with compensation an airline gives me if it denies me a seat on a plane?

    Science.gov (United States)

    2010-07-01

    ... compensation an airline gives me if it denies me a seat on a plane? 301-10.116 Section 301-10.116 Public... plane? If you are performing official travel and a carrier denies you a confirmed reserved seat on a plane, you must give your agency any payment you receive for liquidated damages. You must ensure...

  10. Advanced median method for timing jitter compensation

    Institute of Scientific and Technical Information of China (English)

    Wang Chen; Zhu Jiangmiao; Jan Verspecht; Liu Mingliang; Li Yang

    2008-01-01

    Timing jitter is one of the main factors that influence on the accuracy of time domain precision measurement. Timing jitter compensation is one of the problems people concern. Because of the flaws of median method, PDF deconvolution method and synthetic method, we put forward a new method for timing jitter compensation, which is called advanced median method. The theory of the advanced median method based on probability and statistics is analyzed, and the process of the advanced median method is summarized in this paper. Simulation and experiment show that compared with other methods, the new method could compensate timing jitter effectively.

  11. Zero energy buildings and mismatch compensation factors

    DEFF Research Database (Denmark)

    Lund, Henrik; Marszal, Anna Joanna; Heiselberg, Per

    2011-01-01

    individual buildings and an element of economy of scale. For these three reasons mismatches should be dealt with at the aggregated level and not at the individual level of each building. Instead, this paper suggests to compensate the mismatch of a building by increasing (or decreasing) the capacity of the...... energy production unit. Based on historical data for the electricity supply area in western Denmark, this paper makes a first attempt to quantify mismatch compensation factors. The results indicate that such compensation factors are a little below one for buildings with photovoltaics (PV) and a little...

  12. A Study on Compensation for Advertisement Translation

    Institute of Scientific and Technical Information of China (English)

    杨兰兰

    2012-01-01

    Considering the linguistic and cultural difference between English and Chinese, it is inevitable to lose the original musical beauty, visual beauty and original rhetorical devices in advertisements translation. So compensation measures are always taken to compensate the lost information. This paper focuses on the discussion of the features of advertisement, cultural and linguistic differences between English and Chinese advertisements, which result in the loss of information. And compensation strategies on words, musical beauty and rhetorical devices in advertisement translation are introduced in this paper.

  13. On the compensation effect in heterogeneous catalysis

    DEFF Research Database (Denmark)

    Pedersen, Thomas Bligaard; Honkala, Johanna Karoliina; Logadottir, Ashildur;

    2003-01-01

    to illustrate the effect. Both experiments and a detailed kinetic model show a compensation effect. Second, we use density functional theory calculations to show that the compensation effect is not only due to changes in the activation barrier and prefactor of the rate-determining step, N-2 dissociation. We......For a class of heterogeneously catalyzed reactions, we explain the compensation effect in terms of a switching of kinetic regimes leading to a concomitant change in the apparent activation energy and in the prefactor for the overall rate of the reaction. We first use the ammonia synthesis...

  14. Low-cost carriers fare competition effect

    OpenAIRE

    Carmona Benitez, R.B.; Lodewijks, G.

    2010-01-01

    This paper examines the effects that low-cost carriers (LCC’s) produce when entering new routes operated only by full-service carriers (FSC’s) and routes operated by low-cost carriers in competition with full-service carriers. A mathematical model has been developed to determine what routes should be operated by a low-cost carrier with better possibilities to subsist. The proposed model in this paper was set up by analyzing The United States domestic air transport market 2005 year database fr...

  15. Concentration device

    DEFF Research Database (Denmark)

    2013-01-01

    A concentration device (2) for filter filtration concentration of particles (4) from a volume of a fluid (6). The concentration device (2) comprises a filter (8) configured to filter particles (4) of a predefined size in the volume of the fluid (6). The concentration device (2) comprises...

  16. Impact of carriers in oral absorption

    DEFF Research Database (Denmark)

    Gram, Luise Kvisgaard; Rist, Gerda Marie; Lennernäs, Hans; Steffansen, Bente

    Carriers may mediate the permeation across enterocytes for drug substances being organic anions. Carrier mediated permeation for the organic anions estrone-3-sulfate (ES) and glipizide across Caco-2 cells were investigated kinetically, and interactions on involved carriers evaluated. Initial...... with K(m) 44microM and 38microM, respectively. BCRP inhibition affected both absorptive an exsorptive P(EPA) and P(APP) for ES. Glipizide apical P(UP) and absorptive P(APP) were not inhibitable. Basolateral P(UP) for glipizide was inhibitable, its P(EPA) prevented, and P(UP) was saturable with K(m) 56......microM, but exsorptive P(APP) was not affected. Carrier mediated exsorption kinetics for ES are seen at both apical and basolateral membranes, resulting in predominant exsorption despite presence of absorptive carrier(s). Carrier mediated basolateral P(UP) for glipizide was observed, but glipizide P...

  17. Spectroscopy of Charge Carriers and Traps in Field-Doped Single Crystal Organic Semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xiaoyang

    2014-12-10

    The proposed research aims to achieve quantitative, molecular level understanding of charge carriers and traps in field-doped crystalline organic semiconductors via in situ linear and nonlinear optical spectroscopy, in conjunction with transport measurements and molecular/crystal engineering. Organic semiconductors are emerging as viable materials for low-cost electronics and optoelectronics, such as organic photovoltaics (OPV), organic field effect transistors (OFETs), and organic light emitting diodes (OLEDs). Despite extensive studies spanning many decades, a clear understanding of the nature of charge carriers in organic semiconductors is still lacking. It is generally appreciated that polaron formation and charge carrier trapping are two hallmarks associated with electrical transport in organic semiconductors; the former results from the low dielectric constants and weak intermolecular electronic overlap while the latter can be attributed to the prevalence of structural disorder. These properties have lead to the common observation of low charge carrier mobilities, e.g., in the range of 10-5 - 10-3 cm2/Vs, particularly at low carrier concentrations. However, there is also growing evidence that charge carrier mobility approaching those of inorganic semiconductors and metals can exist in some crystalline organic semiconductors, such as pentacene, tetracene and rubrene. A particularly striking example is single crystal rubrene (Figure 1), in which hole mobilities well above 10 cm2/Vs have been observed in OFETs operating at room temperature. Temperature dependent transport and spectroscopic measurements both revealed evidence of free carriers in rubrene. Outstanding questions are: what are the structural features and physical properties that make rubrene so unique? How do we establish fundamental design principles for the development of other organic semiconductors of high mobility? These questions are critically important but not comprehensive, as the nature of

  18. Concentrated Ownership

    DEFF Research Database (Denmark)

    Rose, Caspar

    2014-01-01

    This entry summarizes the main theoretical contributions and empirical findings in relation to concentrated ownership from a law and economics perspective. The various forms of concentrated ownership are described as well as analyzed from the perspective of the legal protection of investors......, especially minority shareholders. Concentrated ownership is associated with benefits and costs. Concentrated ownership may reduce agency costs by increased monitoring of top management. However, concentrated ownership may also provide dominating owners with private benefits of control....

  19. Neural nets and chaotic carriers

    CERN Document Server

    Whittle, Peter

    2010-01-01

    ""Neural Nets and Chaotic Carriers"" develops rational principles for the design of associative memories, with a view to applying these principles to models with irregularly oscillatory operation so evident in biological neural systems, and necessitated by the meaninglessness of absolute signal levels. Design is based on the criterion that an associative memory must be able to cope with 'fading data', i.e., to form an inference from the data even as its memory of that data degrades. The resultant net shows striking biological parallels. When these principles are combined with the Freeman speci

  20. Carrier frequencies, holomorphy and unwinding

    CERN Document Server

    Coifman, Ronald R; Wu, Hau-tieng

    2016-01-01

    We prove that functions of intrinsic-mode type (a classical models for signals) behave essentially like holomorphic functions: adding a pure carrier frequency $e^{int}$ ensures that the anti-holomorphic part is much smaller than the holomorphic part $ \\| P_{-}(f)\\|_{L^2} \\ll \\|P_{+}(f)\\|_{L^2}.$ This enables us to use techniques from complex analysis, in particular the \\textit{unwinding series}. We study its stability and convergence properties and show that the unwinding series can stabilize and show that the unwinding series can provide a high resolution time-frequency representation, which is robust to noise.

  1. Technetium diagnostic agent and carrier

    International Nuclear Information System (INIS)

    A stable sup(99m)Tc-labelled radioactive diagnostic agent is produced by contacting sup(99m)Tc-containing pertechnetate with a non-radioactive carrier comprising a chelating agent, a water-soluble reducing agent and a stabilizer. The stabilizer is chosen from ascorbic acid and erythorbic acid and their pharmaceutically acceptable salts and esters. A mole ratio of more than 100 moles ascorbic or erythorbic acid to 1 mole of reducing agent provides a stable composition at high levels of radioactivity

  2. Wuestite - a solar energy carrier

    Energy Technology Data Exchange (ETDEWEB)

    Weidenkaff, A.; Nueesch, P.; Wokaun, A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Reller, A. [Hamburg Univ., Hamburg (Germany)

    1997-06-01

    Hydrogen is produced when Wuestite (Fe{sub 1-y}O) is oxidised by water. This reaction is part of a two-step thermochemical metal oxide cycle for the storage of solar energy in the form of chemical energy carriers, characterised by a high chemical potential. The reaction was studied in a tubular furnace with on-line gas analysis and further characterised in detail by DTA und high-temperature X-ray powder diffraction. The influence of non-stoichiometry, morphology and temperature on the mechanism and kinetics of the water-splitting reaction was determined. (author) 3 figs., tabs., 3 refs.

  3. Compensating for estimation smoothing in kriging

    Science.gov (United States)

    Olea, R.A.; Pawlowsky, Vera

    1996-01-01

    Smoothing is a characteristic inherent to all minimum mean-square-error spatial estimators such as kriging. Cross-validation can be used to detect and model such smoothing. Inversion of the model produces a new estimator-compensated kriging. A numerical comparison based on an exhaustive permeability sampling of a 4-fr2 slab of Berea Sandstone shows that the estimation surface generated by compensated kriging has properties intermediate between those generated by ordinary kriging and stochastic realizations resulting from simulated annealing and sequential Gaussian simulation. The frequency distribution is well reproduced by the compensated kriging surface, which also approximates the experimental semivariogram well - better than ordinary kriging, but not as well as stochastic realizations. Compensated kriging produces surfaces that are more accurate than stochastic realizations, but not as accurate as ordinary kriging. ?? 1996 International Association for Mathematical Geology.

  4. Convention on supplementary compensation for nuclear damage

    International Nuclear Information System (INIS)

    The document reproduces the text of the Convention on Supplementary Compensation for Nuclear Damage which was adopted on 12 September 1997 by a Diplomatic Conference held between 8-12 September 1997 in Vienna

  5. Comprehensive Environmental Response, Compensation and Liability Act

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), commonly known as Superfund, provides a federal "superfund" to clean up...

  6. Compensation temperatures of mixed ferro-ferrimagnetic ternary alloys

    International Nuclear Information System (INIS)

    We present a Monte Carlo study of a mixed Ising model of the type ABPC1-P, in a square lattice, were spins SA=+/-3/2,+/-1/2 of one sublattice are in alternating sites with spins SB=+/-52,+/-32,+/-12 or spins SC=+/-1,0, located on the other sublattice with concentrations P and 1-P, respectively. The SA interact ferromagnetically with the SB and antiferromagnetically with the SC. The results indicate that this simple model can reproduce several aspects of the behavior of a class of molecular compounds called Prussian blue analogs such as a critical temperature that it is independent on the concentration of different types of spins, and the appearance of compensation temperatures in a certain range of values of the concentration of the different species

  7. 78 FR 66801 - Motor Carrier Safety Advisory Committee; Charter Renewal

    Science.gov (United States)

    2013-11-06

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee; Charter Renewal AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION: Announcement of advisory... Committee that provides the Agency with advice and recommendations on motor carrier safety programs...

  8. Charge carrier dynamics in thin film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Strothkaemper, Christian

    2013-06-24

    This work investigates the charge carrier dynamics in three different technological approaches within the class of thin film solar cells: radial heterojunctions, the dye solar cell, and microcrystalline CuInSe{sub 2}, focusing on charge transport and separation at the electrode, and the relaxation of photogenerated charge carriers due to recombination and energy dissipation to the phonon system. This work relies mostly on optical-pump terahertz-probe (OPTP) spectroscopy, followed by transient absorption (TA) and two-photon photoemission (2PPE). The charge separation in ZnO-electrode/In{sub 2}S{sub 3}-absorber core/shell nanorods, which represent a model system of a radial heterojunction, is analyzed by OPTP. It is concluded, that the dynamics in the absorber are determined by multiple trapping, which leads to a dispersive charge transport to the electrode that lasts over hundreds of picoseconds. The high trap density on the order of 10{sup 19}/cm{sup 3} is detrimental for the injection yield, which exhibits a decrease with increasing shell thickness. The heterogeneous electron transfer from a series of model dyes into ZnO proceeds on a time-scale of 200 fs. However, the photoconductivity builds up just on a 2-10 ps timescale, and 2PPE reveals that injected electrons are meanwhile localized spatially and energetically at the interface. It is concluded that the injection proceeds through adsorbate induced interface states. This is an important result because the back reaction from long lived interface states can be expected to be much faster than from bulk states. While the charge transport in stoichiometric CuInSe{sub 2} thin films is indicative of free charge carriers, CuInSe{sub 2} with a solar cell grade composition (Cu-poor) exhibits signs of carrier localization. This detrimental effect is attributed to a high density of charged defects and a high degree of compensation, which together create a spatially fluctuating potential that inhibits charge transport. On

  9. Compensating fields and anomalies in supergravity

    International Nuclear Information System (INIS)

    We discuss the quantization of theories which are formulated using compensating fields. In particular, we discuss the relation between the components formulation and the superspace formulation of supergravity theories. The requirement that the compensating field can be eliminated at the quantum level gives rise to on-shell constraints on the operators of the theory. In some cases, the constraints turn out to be physically unacceptable. Using these considerations we show that new minimal supergravity is in general anomalous. (author). 17 refs

  10. Compensating Fields and Anomalies in Supergravity

    CERN Document Server

    Shamir, Y

    1993-01-01

    We discuss the quantization of theories which are formulated using compensating fields. In particular, we discuss the relation between the components formulation and the superspace formulation of supergravity theories. The requirement that the compensating field can be eliminated at the quantum level gives rise to on-shell constraints on the operators of the theory. In some cases, the constraints turn out to be physically unacceptable. Using these considerations we show that new minimal supergravity is in general anomalous.

  11. Stock Option Compensation and Managerial Turnover

    OpenAIRE

    Raluca Georgiana NASTASESCU

    2009-01-01

    This study examines the association between managerial turnover and equity-based compensation. I investigate whether stock options act to bond executives to their firms and whether retention of managers is a motivation of companies in designing CEO incentive contracts. The results show that stock options do negatively influence the probability of a CEO leaving the company. The monetary cost of losing the value of equity-based compensation package keeps the manager with his company. I also fin...

  12. Empirical Evidence of Recurring International Compensation Problems

    OpenAIRE

    Michael Harvey

    1993-01-01

    The expansion of international business necessitates an increased number of employees based in foreign markets. These expatriates, nationals and third-country nationals represent unique and complex compensation problems. This article addresses five of the recurring compensation problems reported by members of the Society for Human Resource Management International (SHRMI) in a recent survey.© 1993 JIBS. Journal of International Business Studies (1993) 24, 785–799

  13. Reversible thyristor converters of brushless synchronous compensators

    OpenAIRE

    А.М. Galynovskiy; E.М.Dubchak; E.А. Lenskaya

    2013-01-01

    Behavior of models of three-phase-to-single-phase rotary reversible thyristor converters of brushless synchronous compensators in a circuit simulation system is analyzed. It is shown that combined control mode of opposite-connected thyristors may result in the exciter armature winding short circuits both at the thyristor feed-forward and lagging current delay angles. It must be taken into consideration when developing brushless compensator excitation systems.

  14. Job Dispersion and Compensating Wage Differentials

    OpenAIRE

    Paul Sullivan; Ted To

    2013-01-01

    The empirical literature on compensating wage differentials has a mixed history. While there have been some successes, much of this literature finds weak support for the theory of equalizing differences. We argue that it is dispersion in total job values or "job dispersion" that leads to biased compensating wage differential estimates. We begin by demonstrating how job dispersion can lead to biased hedonic estimates. Then we take a partial equilibrium on-the-job search model with utility from...

  15. Temperature-Compensating Inactive Strain Gauge

    Science.gov (United States)

    Moore, Thomas C., Sr.

    1993-01-01

    Thermal contribution to output of active gauge canceled. High-temperature strain gauges include both active gauge wires sensing strains and inactive gauge wires providing compensation for thermal contributions to gauge readings. Inactive-gauge approach to temperature compensation applicable to commercially available resistance-type strain gauges operating at temperatures up to 700 degrees F and to developmental strain gauges operating at temperatures up to 2,000 degrees F.

  16. Executive compensation based on asset values

    OpenAIRE

    Hans Bystrom

    2012-01-01

    This paper describes how credit default swaps could be employed to create performance based executive compensation portfolios that reflect the value of a firm's debt as well as equity; i.e. the total value of all a firm's assets. We define so-called Asset Value Unit (AVU) compensation portfolios that work both for executive- and non-executive pay schemes in financial as well as non-financial firms.

  17. Executive Compensation and Misconduct: Environmental Harm

    OpenAIRE

    Minor, Dylan Blu

    2016-01-01

    We explore the relationship between managerial incentives and misconduct using the setting of environmental harm. We find that high powered executive compensation can increase the odds of environmental law-breaking by 40-60% and the magnitude of environmental harm by over 100%. We document similar results for the setting of executive compensation and illegal financial accounting. Finally, we outline some managerial and policy implications to blunt these adverse incentive effects.

  18. Environmental compensation is not for the birds

    OpenAIRE

    Cole, Scott

    2012-01-01

    The European Union (EU) recently implemented the Environmental Liability Directive (ELD), requiring that environmental damage be restored so that the affected environment returns to (or toward) its baseline condition and the public is compensated for the initial damage and the losses during the time it takes for the environment to recover (interim losses). Equivalency Analysis (EA) represents a method for scaling environmental compensation to offset interim losses. Ensuring appropriate compen...

  19. Compensation and Incentives in German Corporations

    OpenAIRE

    Moritz Heimes; Steffen Seemann

    2011-01-01

    In this paper we analyze executive compensation in Germany for the period 2005-2009. We use a self-collected dataset on compensation arrangements in German corporations to estimate the impact of firm performance and firm risk on executive pay. To be in line with earlier studies in this literature, we first measure firm performance and firm risk based on stock market returns. Our findings support the prediction from agency theory that incentive pay decreases with firm risk. We find, however, t...

  20. Reactive power compensation a practical guide

    CERN Document Server

    Hofmann, Wolfgang; Just, Wolfgang

    2012-01-01

    The comprehensive resource on reactive power compensation, presenting the design, application and operation of reactive power equipment and installations The area of reactive power compensation is gaining increasing importance worldwide. If suitably designed, it is capable of improving voltage quality significantly, meaning that losses in equipment and power systems are reduced, the permissible loading of equipment can be increased, and the over-all stability of system operation improved. Ultimately, energy use and CO2 emisson are reduced. This unique guide discusses the

  1. Improved charge amplifier using hybrid hysteresis compensation

    Science.gov (United States)

    Amin-Shahidi, Darya; Trumper, David L.

    2013-08-01

    We present a novel charge amplifier, with a robust feedback circuit and a method for compensating piezoelectric actuator's hysteresis at low frequencies. The amplifier uses a modified feedback circuit which improves robustness to the addition of series load impedance such as in cabling. We also describe a hybrid hysteresis compensation method for enabling the charge amplifier to reduce hysteresis at low frequencies. Experimental results demonstrate the utility of the new amplifier design.

  2. Reversible thyristor converters of brushless synchronous compensators

    Directory of Open Access Journals (Sweden)

    А.М.Galynovskiy

    2013-12-01

    Full Text Available Behavior of models of three-phase-to-single-phase rotary reversible thyristor converters of brushless synchronous compensators in a circuit simulation system is analyzed. It is shown that combined control mode of opposite-connected thyristors may result in the exciter armature winding short circuits both at the thyristor feed-forward and lagging current delay angles. It must be taken into consideration when developing brushless compensator excitation systems.

  3. Executive equity compensation and incentives: a survey

    OpenAIRE

    Core, John E.; Wayne R. Guay; David F. Larcker

    2003-01-01

    Stock and option compensation and the level of managerial equity incentives are aspects of corporate governance that are especially controversial to shareholders, institutional activists, and government regulators. Similar to much of the corporate finance and corporate governance literature, research on stock-based compensation and incentives has not only generated useful insights, but also produced many contradictory findings. Not surprisingly, many fundamental questions remain unanswered. I...

  4. Compensating Heterogeneous Salesforces: Some Explicit Solutions

    OpenAIRE

    Ram C. Rao

    1990-01-01

    This paper considers the question of how a sales manager should design the optimal compensation scheme for his salesforce when it consists of salespersons of varying selling skills, i.e., when the salesforce is heterogeneous. The manager's problem is to reward the salespersons based on observable, uncertain sales achieved by the salespersons. Under the assumption that both the manager and the salespersons are risk neutral, the optimal compensation scheme is derived. It consists of the manager...

  5. Executive Compensation as an Agency Problem

    OpenAIRE

    Lucian A. Bebchuk; Fried, Jesse M.

    2003-01-01

    This paper provides an overview of the main theoretical elements and empirical underpinnings of a "managerial power" approach to executive compensation. Under this approach, the design of executive compensation is viewed not only as an instrument for addressing the agency problem between managers and shareholders but also as part of the agency problem itself. Boards of publicly traded companies with dispersed ownership, we argue, cannot be expected to bargain at arm's length with managers. As...

  6. Overcoming maladaptive plasticity through plastic compensation

    Institute of Scientific and Technical Information of China (English)

    Matthew R.J.MORRIS; Sean M.ROGERS

    2013-01-01

    Most species evolve within fluctuating environments,and have developed adaptations to meet the challenges posed by environmental heterogeneity.One such adaptation is phenotypic plasticity,or the ability of a single genotype to produce multiple environmentally-induced phenotypes.Yet,not all plasticity is adaptive.Despite the renewed interest in adaptive phenotypic plasticity and its consequences for evolution,much less is known about maladaptive plasticity.However,maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments.This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity,two of which involve genetic changes (standing genetic variation,genetic compensation) and two of which do not (standing epigenetic variation,plastic compensation).Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity.In particular,plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence.We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for understanding evolutionary change.

  7. Carrier detection in xeroderma pigmentosum

    International Nuclear Information System (INIS)

    We were able to detect clinically normal carriers of xeroderma pigmentosum (XP) genes with coded samples of either peripheral blood lymphocytes or skin fibroblasts, using a cytogenetic assay shown previously to detect individuals with cancer-prone genetic disorders. Metaphase cells of phytohemagglutinin-stimulated T-lymphocytes from eight individuals who are obligate heterozygotes for XP were compared with those from nine normal controls at 1.3, 2.3, and 3.3 h after x-irradiation (58 R) during the G2 phase of the cell cycle. Lymphocytes from the XP heterozygotes had twofold higher frequencies of chromatid breaks or chromatid gaps than normal (P less than 10(-5)) when fixed at 2.3 or 3.3 h after irradiation. Lymphocytes from six XP homozygotes had frequencies of breaks and gaps threefold higher than normal. Skin fibroblasts from an additional obligate XP heterozygote, when fixed approximately 2 h after x-irradiation (68 R), had a twofold higher frequency of chromatid breaks and a fourfold higher frequency of gaps than fibroblasts from a normal control. This frequency of aberrations in cells from the XP heterozygote was approximately half that observed in the XP homozygote. The elevated frequencies of chromatid breaks and gaps after G2 phase x-irradiation may provide the basis of a test for identifying carriers of the XP gene(s) within known XP families

  8. The influence of drug loading on formulation structure and aerosol performance in carrier based dry powder inhalers.

    Science.gov (United States)

    Young, Paul M; Wood, Owen; Ooi, Jesslynn; Traini, Daniela

    2011-09-15

    Previous studies have reported that carrier:drug ratio and carrier size influence the aerosol performance of dry powder inhalation systems. These previous studies were complicated by the heterogeneous nature of the carriers used, making it difficult to define an explicit relationship between parameters and performance. Here, the authors studied the influence of drug loading and carrier size on drug aerosol performance using homogeneous spherical model carriers. Different formulations containing drug (salbutamol sulphate) and carriers (polystyrene beads with median diameters of 82.8μm, 277.5μm and 582.9μm, respectively) were prepared by varying the ratio of carrier to drug (from ∼5:1 to ∼85:1). The surface morphology of the carrier particles and force of adhesion were investigated using atomic force microscopy, while the aerosol performance was evaluated using a multi-stage liquid impinger. The carrier surface morphology for all carrier sizes was homogenous with root-mean square roughness values ≤112nm. No significant difference in the force of adhesion between salbutamol sulphate and the three carrier sizes was observed. Significant differences in aerosol performance of salbutamol sulphate (measured as fine particle dose (FPD) and fraction (FPF)≤5μm) from the carriers were observed. Specifically, as carrier size increased FPF decreased. In comparison, as drug loading increased there was no change in FPF until a critical threshold was exceeded. Such observations suggest that: (A) aerosolisation performance is governed by carrier collisions and (B) when homogeneous carriers are used, the aerosol performance remains constant with respect to drug concentration, until the formulation transitions from an ordered mix to an agglomerated and/or segregated powder bed. PMID:21708238

  9. A new look at gravel pack carrier fluid properties

    Energy Technology Data Exchange (ETDEWEB)

    Scheuerman, R.F.

    1984-02-01

    For gravel pack carrier fluids, less viscosity is needed downhole than for suspending and pumping high gravel loadings on the surface. To achieve this dual viscosity need, breakers are added to degrade the viscosifying polymers. Unfortunately, viscosity breakback criteria are not well defined. In addition to the type and concentration of breaker and temperature, the apparent viscosity breakback time of a polymer solution also depends on the shear rate at which the viscosity is measured. As a result, industry breakback data generally disagree because of the variety of instruments and shear rates used to measure viscosity. This paper discusses two new viscosity breakback criteria for gravel packing carrier fluids: The time for the apparent viscosity at 0.03 sec/sup -1/ to decrease to 1000 cp, and start of compaction of the settled gravel bed. These criteria correlate well with fluid performance and apply to slurries with different initial viscosities (including crosslinked gels), brine densities, and gravel sizes. Data useful for formulating gravel pack carrier fluids are also presented. Although this paper does not define optimum downhole carrier fluid properties, the new criteria reflect downhole conditions better than most previous criteria. They should give better correlation with model studies and field experience, and, in turn, lead to a better understanding of the requirements for optimum downhole performance.

  10. Develop a novel superparamagnetic nano-carrier for drug delivery to brain glioma.

    Science.gov (United States)

    Zhao, Ming; Li, Anmin; Chang, Jin; Fu, Xiangping; Zhang, Zhiwen; Yan, Runmin; Wang, Hanjie; Liang, Shuli

    2013-01-01

    Magnetic drug carrier has been employed in drug delivery for over 30 years. Modern nanotechnology has improved its efficiency dramatically by decreasing its diameter into nano-scale. It may help chemotherapeutic agents penetrate BBB and raise local drug concentration in brain, which is the ideal model for glioma treatment. In our study, magnetic carrier was fabricated with octadecyl quaternized caroxymethyl chitosan (OQCMC), hydrophobic Fe₃O₄ ferrofluid and cholesterol, which showed a uniform diameter of 20 nm under transmission electronic microscopy and superparamagnetic character in vibration sample magnetical measurement system. To investigate the efficacy of drug delivery, paclitaxel was used as loaded drug and analyzed by the HPLC. Results showed that magnetic carrier released drugs for more than 20 d in vitro and maintain the drug concentration above 0.4 μg/g for 16 h in rat brain after magnetic targeting. Drug concentration increased by 1-3 folds when delivered by carrier without magnetic targeting, and by 3-15 folds after magnetic targeting. Cellular study revealed that the magnetic carrier was clearly localized in the targeted cortex neural cells and U251-MG cell lines. These results showed that this magnetic carrier is capable of maintaining high drug concentration in magnetically targeted area and carrying drugs or genes into cells, which is potentially promising for local chemotherapy to brain tumors. PMID:23701032

  11. Recent Advances in Subunit Vaccine Carriers.

    Science.gov (United States)

    Vartak, Abhishek; Sucheck, Steven J

    2016-01-01

    The lower immunogenicity of synthetic subunit antigens, compared to live attenuated vaccines, is being addressed with improved vaccine carriers. Recent reports indicate that the physio-chemical properties of these carriers can be altered to achieve optimal antigen presentation, endosomal escape, particle bio-distribution, and cellular trafficking. The carriers can be modified with various antigens and ligands for dendritic cells targeting. They can also be modified with adjuvants, either covalently or entrapped in the matrix, to improve cellular and humoral immune responses against the antigen. As a result, these multi-functional carrier systems are being explored for use in active immunotherapy against cancer and infectious diseases. Advancing technology, improved analytical methods, and use of computational methodology have also contributed to the development of subunit vaccine carriers. This review details recent breakthroughs in the design of nano-particulate vaccine carriers, including liposomes, polymeric nanoparticles, and inorganic nanoparticles. PMID:27104575

  12. Inert carriers for column extraction chromatography

    International Nuclear Information System (INIS)

    Inert carriers used in column extraction chromatography are reviewed. Such carriers are devided into two large groups: hydrophilic carriers which possess high surface energy and are well wetted only with strongly polar liquids (kieselguhrs, silica gels, glasses, cellulose, Al2O3) and water-repellent carriers which possess low surface energy and are well wetted with various organic solvents (polyethylene, polytetrafluorethylene polytrifluorochlorethylene). Properties of various carriers are presented: structure, chemical and radiation stability, adsorption properties, extracting agent capacity. The effect of structure and sizes of particles on the efficiency of chromatography columns is considered. Ways of immovable phase deposition on the carrier and the latter's regeneration. Peculiarities of column packing for preparative and continuous chromatography are discussed

  13. Selective labeling of the erythrocyte hexose carrier with a maleimide derivative of glucosamine: Relationship of an exofacial sulfhydryl to carrier conformation and structure

    International Nuclear Information System (INIS)

    Sulfhydryl-reactive derivatives of glucosamine were synthesized as potentially transportable affinity labels of the human erythrocyte hexose carrier. N-maleoylglycyl derivatives of either 6- or 2-amino-2-deoxy-D-glucopyranose were the most potent inhibitors of 3-O-methylglucose uptake, with concentrations of half-maximal irreversible inhibition of about 1 mM. Surprisingly, these derivatives were very poorly transported into erythrocytes. They reacted rather with an exofacial sulfhydryl on the carrier following a reversible binding step, the latter possibly to the exofacial substrate binding site. However, their reactivity was determined primarily by access to the exofacial sulfhydryl, which, as predicted by the one-site model of transport, required a carrier conformation with the exofacial substrate binding site exposed. Once reacted, the carrier was locked in a conformation unable to reorient inwardly and bind cytochalasin B. In intact erythrocytes the N-maleoylglycyl derivative of 2-[3H]glucosamine labeled predominantly an Mr 45,000-66,000 protein on gel electrophoresis in a quantitative and cytochalasin B inhibitable fashion. By use of changes in carrier conformation induced by competitive transport inhibitors in a double differential labeling method, virtually complete selectivity of labeling of the carrier protein was achieved, the latter permitting localization of the reactive exofacial sulfhydryl to an Mr 18,000-20,000 tryptic fragment of the carrier

  14. Concentrator Photovoltaics

    CERN Document Server

    Luque, Antonio L

    2007-01-01

    Photovoltaic solar-energy conversion is one of the most promising technologies for generating renewable energy, and conversion of concentrated sunlight can lead to reduced cost for solar electricity. In fact, photovoltaic conversion of concentrated sunlight insures an efficient and cost-effective sustainable power resource. This book gives an overview of all components, e.g. cells, concentrators, modules and systems, for systems of concentrator photovoltaics. The authors report on significant results related to design, technology, and applications, and also cover the fundamental physics and market considerations. Specific contributions include: theory and practice of sunlight concentrators; an overview of concentrator PV activities; a description of concentrator solar cells; design and technology of modules and systems; manufacturing aspects; and a market study.

  15. Global Telecommunications Services: Strategies of Major Carriers

    OpenAIRE

    Jerry Mccreary; William R. Boulton; Chetan Sankar

    1993-01-01

    The globalization of telecommunications markets is of primary concern for today’s large telecommunications carriers. International business telecommunications is growing at a rate twice that of domestic traffic. Multi-national customers with offices around the world are demanding integrated solutions to their telecommunications needs. As telecommunication carriers respond to these customers’ needs, the carriers are beginning to expand outside their national boundaries. This paper identifi...

  16. Free carrier absorption in quantum cascade structures

    OpenAIRE

    Carosella, F.; Ndebeka-Bandou, C.; Ferreira, R.; Dupont, E; K. Unterrainer; Strasser, G.; Wacker, Andreas; Bastard, G.

    2011-01-01

    We show that the free carrier absorption in Quantum Cascade Lasers is very small and radically different from the classical Drude result on account of the orthogonality between the direction of the carrier free motion and the electric field of the laser emission. A quantum mechanical calculation of the free carrier absorption and inter-subband oblique absorption induced by interface defects, coulombic impurities and optical phonon absorption/emission is presented for QCL's with a double quant...

  17. Secure quantum carriers for quantum state sharing

    OpenAIRE

    Karimipour, Vahid; Marvian, Milad

    2010-01-01

    We develop the concept of quantum carrier and show that messages can be uploaded and downloaded from this carrier and while in transit, these messages are hidden from external agents. We explain in detail the working of the quantum carrier for different communication tasks, including quantum key distribution, classical secret and quantum state sharing among a set of $n$ players according to general threshold schemes. The security of the protocol is discussed and it is shown that only the legi...

  18. Heterozygote advantage in Tay-Sachs carriers?

    OpenAIRE

    Spyropoulos, B; Moens, P B; Davidson, J.; Lowden, J. A.

    1981-01-01

    Chi-square analyses of new data as well as data previously reported by Myrianthopoulos have shown that grandparents of Tay-Sachs carriers die from proportionally the same causes as grandparents of noncarriers. It is unlikely that there is any advantage to being a Tay-Sachs carrier insofar as resistance to tuberculosis is concerned. Our results are further evidence to support Fraikor's claim that the high carrier frequency of the allele in Ashkenazi Jews is probably caused by a combination of ...

  19. Dispersion-compensated fresnel lens

    Science.gov (United States)

    Johnson, Kenneth C.

    1992-01-01

    A transmission grating is used to reduce chromatic aberration in a Fresnel lens, wherein the lens chromatic dispersion is offset and substantially canceled by the grating's diffraction-induced dispersion. The grating comprises a Fresnel-type pattern of microscopic facets molded directly into the lens surface. The facets would typically have a profile height of around 4.multidot.10.sup.-5 inch and a profile width of at least 10.sup.-3 inch. In its primary intended application, the invention would function to improve the optical performance of a Fresnel lens used to concentrate direct sunlight.

  20. Multi-carrier technologies for wireless communication

    CERN Document Server

    Nassar, Carl R; Wu, Zhiqiang; Wiegandt, David A; Zekavat, S Alireza; Shattil, Steve

    2006-01-01

    1. Introduction. 2. Overview of Multi-Carrier Technologies. 3. High-Performance High-Capacity MC-CDMA for Future Generations: The CI Approach. 4. High Performance, High Throughput TDMA via Multi-Carrier Implementations. 5. High-Performance, High-Capacity DS-CDMA via Multicarrier Implementation. 6. High-Performance, High-Throughput OFDM with Low PAPR via Carrier Interferometry Phase Coding. 7. The Marriage of Smart Antenna Arrays and Multi-Carrier Systems: Spatial Sweeping, Transmit Diversity, and Directionality. Index.

  1. Measurement of charge carrier lifetimes in HgCdTe crystals

    International Nuclear Information System (INIS)

    A method, developed for the determination of both electrical and photoelectrical properties of the same Hgsub(1-x)Cdsub(x)Te samples (around x=0.2), is presented. A system which includes a pulsed 0.9 μm wavelength GaAs light source was designed and constructed for the measurement of charge carrier lifetimes from 20 ns to 20 ms in temperature range 80-300 K. To find the mobility and concentration of the charge carriers, the Hall effect was determined via the van der Pauw method. Electrical and photoelectrical properties of raw material wafers could thus be established. Charge carrier lifetimes in Hgsub(1-x)Cdsub(x)Te, Ge and InSb were measured. The corresponding theoretical expected lifetimes were calculated on the basis of the charge carriers concentration. The experimental results are compared to the theoretical ones and the discrepancies are discussed

  2. Analytic compensation methods in dynamic tomography; Methodes analytiques de compensation des deformations en tomographie dynamique

    Energy Technology Data Exchange (ETDEWEB)

    Roux, S.; Desbat, L.; Koenig, A.; Grangeat, P. [Laboratoire TIMC-IMAG UMR CNRS 5525, Faculte de Medecine de Grenoble, 38 - La Tronche (France)]|[CEA Grenoble, Lab. Electronique et de Technologie de l' Informatique (LETI), 38 (France)

    2004-07-01

    Recent progresses in X-ray tomography allow to study some organs dynamically. The aim of this work is to analyze the deformation compensation algorithms used to integrate dynamical evolution models into the image reconstruction processes. An exact and efficient analytical method of movement compensation is presented and applied to simulated data. Abstract only. (J.S.)

  3. Risk compensation behaviours in construction workers' activities.

    Science.gov (United States)

    Feng, Yingbin; Wu, Peng

    2015-01-01

    The purpose of this study was to test whether the construction workers have the tendency of engaging in risk compensation behaviours, and identify the demographic variables, which may influence the extent to which the construction workers may show risk compensation behaviours. Both quantitative (survey) and qualitative (interviews) approaches were used in this study. A questionnaire survey was conducted with all the construction workers on three building construction sites of a leading construction company in Australia. Semi-structured interviews were then conducted to validate the findings of the quantitative research. The findings indicate that workers tend to show risk compensation behaviours in the construction environment. The workers with more working experience, higher education, or having never been injured at work before have a higher tendency to show risk compensation in their activities than the others. The implication is that contractors need to assess the potential influence of workers' risk compensation behaviours when evaluating the effect of risk control measures. It is recommended that supervisors pay more attention to the behavioural changes of those workers who have more experience, higher education, and have never been injured before after the implementation of new safety control measures on construction site. PMID:24134314

  4. Managerial Stock Compensation and Risky Investment

    Directory of Open Access Journals (Sweden)

    Raluca Georgiana Nastasescu

    2009-06-01

    Full Text Available This study analyzes the relationship between the mix of CEO equity-based compensation, namely stock options and restricted stock, and firms' risky investment. In general, the theory suggests that long-term compensation aligns CEOs' and shareholders' interests by inducing the managers to undertake risky investment, which has a positive impact on longterm well-being of the firm. However, as my results show, it is important to distinguish between types of awards since they can have different effects on the riskiness of the firm. In this respect, I answer the question how are different types of stock based compensation related to the executives' determination to increase or not the intensity of the firm's risky investment? I find that awarding the CEOs preponderantly with stock options positively affects the firm's level of R&D investment. Conversely, a higher proportion of restricted stock in the CEO's compensation is related to lower investment in (risky R&D. The inverse relation of causality also holds. Firms that make intensive R&D investments are more likely to award their CEOs with more stock options relative to restricted stock. Overall, the results are consistent with the theoretical prediction, in that the managerial compensation scheme plays an important role in determining the level of R&D investment.

  5. Temperature compensation and entrainment in circadian rhythms

    International Nuclear Information System (INIS)

    To anticipate daily variations in the environment and coordinate biological activities into a daily cycle many organisms possess a circadian clock. In the absence of external time cues the circadian rhythm persists with a period of approximately 24 h. The clock phase can be shifted by single pulses of light, darkness, chemicals, or temperature and this allows entrainment of the clock to exactly 24 h by cycles of these zeitgebers. On the other hand, the period of the circadian rhythm is kept relatively constant within a physiological range of constant temperatures, which means that the oscillator is temperature compensated. The mechanisms behind temperature compensation and temperature entrainment are not fully understood, neither biochemically nor mathematically. Here, we theoretically investigate the interplay of temperature compensation and entrainment in general oscillatory systems. We first give an analytical treatment for small temperature shifts and derive that every temperature-compensated oscillator is entrainable to external small-amplitude temperature cycles. Temperature compensation ensures that this entrainment region is always centered at the endogenous period regardless of possible seasonal temperature differences. Moreover, for small temperature cycles the entrainment region of the oscillator is potentially larger for rectangular pulses. For large temperature shifts we numerically analyze different circadian clock models proposed in the literature with respect to these properties. We observe that for such large temperature shifts sinusoidal or gradual temperature cycles allow a larger entrainment region than rectangular cycles. (paper)

  6. Do executives get appropriate compensation? : Evidence from intellectual capital perspective

    OpenAIRE

    Xie, Yamin

    2013-01-01

    This paper presents an empirical analysis of top executive compensation from intellectual capital perspective using data from US listed companies and aims to examine whether executives get appropriate compensation. I propose a pay-contribution compensation scheme and extend previous research on agency theory, by exploring how executive compensation contract design may be based on the firm’s intellectual capital (IC). Such features would serve the core purpose of compensation design, which is ...

  7. 14 CFR 221.204 - Adoption of provisions of one carrier by another carrier.

    Science.gov (United States)

    2010-01-01

    ... TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS TARIFFS Electronically Filed Tariffs § 221.204... carrier, the effective and prospective fares of the adopted carrier shall be changed to reflect the...

  8. Automatic Transaction Compensation for Reliable Grid Applications

    Institute of Scientific and Technical Information of China (English)

    Fei-Long Tang; Ming-Lu Li; Joshua Zhexue Huang

    2006-01-01

    As grid technology is expanding from scientific computing to business applications, service oriented grid computing is aimed at providing reliable services for users and hiding complexity of service processes from them. The grid services for coordinating long-lived transactions that occur in business applications play an important role in reliable grid applications. In this paper, the grid transaction service (GridTS) is proposed for dealing with long-lived business transactions. We present a compensation-based long-lived transaction coordination algorithm that enables users to select results from committed sub-transactions. Unlike other long-lived transaction models that require application programmers to develop corresponding compensating transactions, GridTS can automatically generate compensating transactions on execution of a long-lived grid transaction. The simulation result has demonstrated the feasibility of GridTS and effectiveness of the corresponding algorithm.

  9. Compensation: Will it provide a waste site?

    International Nuclear Information System (INIS)

    Offering an attractive compensation package to persuade a community to voluntarily accept an otherwise undesirable facility may work in some cases, but it's not likely to work for high-level nuclear-waste disposal. The public perception of the risks involved and the public distrust of the institutions responsible for managing those risks are just too great. Much of the controversy stems from public perceptions that the site-selection process itself is unfair. Resentment builds when this occurs, and offers of compensation come to be labeled bribes or blood money. The driving force behind current nuclear-waste policy is intergenerational equity - the moral concept that the generation that produced the waste should dispose of it, permanently. Regardless of the moral appeal, doubts have been raised about the technical feasibility of this approach. Alternatives featuring intergenerational monetary compensation may better honor the commitment hor-ellipsis and reduce pressure to try to do what may be impossible

  10. Incomplete and imperfect information for sales compensation

    Directory of Open Access Journals (Sweden)

    Raluca Valeanu

    2010-12-01

    Full Text Available Sales force compensation represents the fix and / or variable payment by the company. To compensate agents based on the results, the company set a goal which is brought to their attention through the compensation plan. Applying the model of moral hazard, where the agent behavior cannot be verified, it cannot be specified in the contract what is the expected behavior of the agent. In order to make an offer to contract principal should know the effort that the agent will submit it to define the payment and the contract is determined optimally in trade between the two conflicting objectives of the two participants in the contract. Although agent behavior cannot be verified, the result of this behavior should be measurable at the end of the contract so that the employer may make the contract contingent on effort commission agent for sale of which is measured by the amount of earnings to the company.

  11. Supersymmetric composite gauge fields with compensators

    Science.gov (United States)

    Nishino, Hitoshi; Rajpoot, Subhash

    2016-06-01

    We study supersymmetric composite gauge theory, supplemented with compensator mechanism. As our first example, we give the formulation of N = 1 supersymmetric non-Abelian composite gauge theory without the kinetic term of a non-Abelian gauge field. The important ingredient is the Proca-Stueckelberg-type compensator scalar field that makes the gauge-boson field equation non-singular, i.e., the field equation can be solved for the gauge field algebraically as a perturbative expansion. As our second example, we perform the gauging of chiral-symmetry for N = 1 supersymmetry in four dimensions by a composite gauge field. These results provide supporting evidence for the consistency of the mechanism that combines the composite gauge field formulations and compensator formulations, all unified under supersymmetry.

  12. Quantum effects on compressional Alfven waves in compensated semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Amin, M. R. [Department of Electronics and Communications Engineering, East West University, Aftabnagar, Dhaka 1212 (Bangladesh)

    2015-03-15

    Amplitude modulation of a compressional Alfven wave in compensated electron-hole semiconductor plasmas is considered in the quantum magnetohydrodynamic regime in this paper. The important ingredients of this study are the inclusion of the particle degeneracy pressure, exchange-correlation potential, and the quantum diffraction effects via the Bohm potential in the momentum balance equations of the charge carriers. A modified nonlinear Schrödinger equation is derived for the evolution of the slowly varying amplitude of the compressional Alfven wave by employing the standard reductive perturbation technique. Typical values of the parameters for GaAs, GaSb, and GaN semiconductors are considered in analyzing the linear and nonlinear dispersions of the compressional Alfven wave. Detailed analysis of the modulation instability in the long-wavelength regime is presented. For typical parameter ranges of the semiconductor plasmas and at the long-wavelength regime, it is found that the wave is modulationally unstable above a certain critical wavenumber. Effects of the exchange-correlation potential and the Bohm potential in the wave dynamics are also studied. It is found that the effect of the Bohm potential may be neglected in comparison with the effect of the exchange-correlation potential in the linear and nonlinear dispersions of the compressional Alfven wave.

  13. MAP detection for impairment compensation in coherent WDM systems.

    Science.gov (United States)

    Zhao, J; Ellis, A D

    2009-08-01

    We propose a novel recursive-algorithm based maximum a posteriori probability (MAP) detector in spectrally-efficient coherent wavelength division multiplexing (CoWDM) systems, and investigate its performance in a 1-bit/s/Hz on-off keyed (OOK) system limited by optical-signal-to-noise ratio. The proposed method decodes each sub-channel using the signal levels not only of the particular sub-channel but also of its adjacent sub-channels, and therefore can effectively compensate deterministic inter-sub-channel crosstalk as well as inter-symbol interference arising from narrow-band filtering and chromatic dispersion (CD). Numerical simulation of a five-channel OOK-based CoWDM system with 10Gbit/s per channel using either direct or coherent detection shows that the MAP decoder can eliminate the need for phase control of each optical carrier (which is necessarily required in a conventional CoWDM system), and greatly relaxes the spectral design of the demultiplexing filter at the receiver. It also significantly improves back-to-back sensitivity and CD tolerance of the system. PMID:19654745

  14. Reactive Power Compensation using a Matrix Converter

    OpenAIRE

    Holtsmark, Nathalie Marie-Anna

    2010-01-01

    This Master's thesis investigates a new application for the matrix converter: Shunt reactive power compensation. The suggested Matrix Converter-based Reactive power Compensation (MCRC) device is composed of a matrix converter, which input is connected to the grid and an electric machine at the output of the converter. The reactive power flowing in or out of the grid can be regulated with the matrix converter by controlling the magnitude and/or phase angle of the current at the input of the co...

  15. Convention on supplementary compensation for nuclear damage

    International Nuclear Information System (INIS)

    The Contracting parties recognize the importance of the measures provided in the Vienna Convention on Civil Liability for Nuclear Damage and the Paris Convention on Third party liability in the Field of Nuclear Energy as well as in national legislation on compensation for nuclear damage consistent with the principles of these conventions. The Contracting parties desire to establish a worldwide liability regime to supplement and enhance these measures with a view to increasing the amount of compensation for nuclear damage and encourage regional and global co-operation to promote a higher level of nuclear safety in accordance with the principle of international partnership and solidarity

  16. Security careers skills, compensation, and career paths

    CERN Document Server

    Walker, Stephen W

    2014-01-01

    The third edition of Security Careers is the authoritative reference for current job descriptions and pay practices of security, compliance, ethics, environmental, health and safety occupations. The job descriptions and compensation ranges in this report are drawn from research from the Foushée Group, which has been conducting this research since 1980. Security Careers includes more than 75 job descriptions for security-related positions, which range from the entry-level security guard to the top global corporate executive. It also provides four years of compensation trend data to give a th

  17. Beam loading compensation in the NLCTA

    International Nuclear Information System (INIS)

    In the design of the Next Linear Collider (NLC), multi-bunch operation is employed to improve efficiency at the cost of substantial beam loading. The RF pulse that powers the accelerator structures will be shaped to compensate for the effect of the transient loading along the bunch train. This scheme has been implemented in the Next Linear Collider Test Accelerator (NLCTA), a facility built to test the key accelerator technology of the NLC. In this paper the authors describe the compensation method, the techniques used to measure the energy variation along the bunch train, and results from tests with NLC-like beam currents

  18. Static compensators (STATCOMs) in power systems

    CERN Document Server

    Shahnia, Farhad; Ghosh, Arindam

    2014-01-01

    A static compensator (STATCOM), also known as static synchronous compensator, is a member of the flexible alternating current transmission system (FACTS) devices. It is a power-electronics based regulating device which is composed of a voltage source converter (VSC) and is shunt-connected to alternating current electricity transmission and distribution networks. The voltage source is created from a DC capacitor and the STATCOM can exchange reactive power with the network. It can also supply some active power to the network, if a DC source of power is connected across the capacitor. A STATCOM

  19. Mesostructured silica and aluminosilicate carriers for oxytetracycline delivery systems.

    Science.gov (United States)

    Berger, D; Nastase, S; Mitran, R A; Petrescu, M; Vasile, E; Matei, C; Negreanu-Pirjol, T

    2016-08-30

    Oxytetracycline delivery systems containing various MCM-type silica and aluminosilicate with different antibiotic content were developed in order to establish the influence of the support structural and textural properties and aluminum content on the drug release profile. The antibiotic molecules were loaded into the support mesochannels by incipient wetness impregnation method using a drug concentrated aqueous solution. The carriers and drug-loaded materials were investigated by small- and wide-angle XRD, FTIR spectroscopy, TEM and N2 adsorption-desorption isotherms. Faster release kinetics of oxytetracycline from uncalcined silica and aluminosilicate supports was observed, whereas higher drug content led to lower delivery rate. The presence of aluminum into the silica network also slowed down the release rate. The antimicrobial assays performed on Staphylococcus aureus clinical isolates showed that the oxytetracycline-loaded materials containing MCM-41-type mesoporous silica or aluminosilicate carriers inhibited the bacterial development. PMID:26861688

  20. Effects of buffer layer preparation and Bi concentration on InGaAsBi epilayers grown by gas source molecular beam epitaxy

    International Nuclear Information System (INIS)

    The effect of using an In0.53Ga0.47As buffer layer on the crystalline quality of InGaAsBi epilayer with Bi concentration up to 3.1% grown by gas source molecular beam epitaxy was investigated. It is found that use of the buffer layer has a dramatic effect on the improvement of surface morphology, structural, electrical and optical properties of InGaAsBi epilayers. Bi incorporation in InGaAs up to a concentration of 3.1% causes no degradation of the electron mobility and induces p-type carriers that compensate the background n-type carriers resulting in mobility enhancement with increasing Bi concentration. With the buffer layer preparation, a maximum electron mobility of 5550 cm2 V–1 s–1 at room temperature is demonstrated in InGaAsBi with x Bi = 3.1%, which is the highest value reported in InGaAsBi with x Bi > 2.5%. (paper)

  1. Inert carrier drying and coating process

    International Nuclear Information System (INIS)

    An inert carrier process is described for drying radioactive (particularly low level) waste material and for incorporating the dry material into a binder matrix from which the dried material will not be leached. Experimental details, and examples of the carrier and binder materials, are given. (U.K.)

  2. Providing resilience for carrier ethernet multicast traffic

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Wessing, Henrik; Zhang, Jiang; Manolova, Anna Vasileva; Rasmussen, Anders; Dittmann, Lars; Berger, Michael Stübert

    2009-01-01

    This paper presents an overview of the Carrier Ethernet technology with specific focus on resilience. In particular, we detail how multicast traffic, which is essential for e.g. IPTV can be protected. We present Carrier Ethernet resilience methods for linear and ring networks and show by simulation...

  3. Towards 100 gigabit carrier ethernet transport networks

    DEFF Research Database (Denmark)

    Rasmussen, Anders; Zhang, Jiang; Yu, Hao;

    2010-01-01

    OAM functions, survivability and the increased bandwidth requirements of carrier class systems. This article provides an overview of PBB-TE and T-MPLS and demonstrates how IPTV services can be realized in the framework of Carrier Ethernet. In addition we provide a case study on performing bit error...

  4. Providing resilience for carrier ethernet multicast traffic

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Wessing, Henrik; Zhang, Jiang;

    2009-01-01

    This paper presents an overview of the Carrier Ethernet technology with specific focus on resilience. In particular, we detail how multicast traffic, which is essential for e.g. IPTV can be protected. We present Carrier Ethernet resilience methods for linear and ring networks and show by simulation...... that the availability of a multicast connection can be significantly increased by applying relevant resilience techniques....

  5. Measurement of HD concentration by gas chromatography

    International Nuclear Information System (INIS)

    Gas chromatography has been used for the on-line measurement of deuterium hydride (HD) which is used in a Tritium Removal Pilot Facility for the demonstration of the removal of the tritium mainly generated in CANDU reactors. Two methods with different carrier gases, neon and hydrogen, are tested and compared each other. It was showed that both the methods could be possible to measure the concentration of H2 and HD. However, the method with a column packed with alumina showed difficulty in the application due to quite long measurement time and reproducibility. The other method using hydrogen as a carrier gas could measure the concentration accurately within comparably short period

  6. Selection of Carrier Waveforms for PWM Inverter

    Institute of Scientific and Technical Information of China (English)

    陈国呈; 屈克庆; 许春雨; 孙承波

    2003-01-01

    In this paper the influence of different carrier waveforms upon the output characteristics of PWM inverter is described in detail. When a triangular carrier waveform is used in hard-switching PWM inverters, harmonics exist in the neighborhood of the output frequency of the inverter output voltage and current due to the dead time. The triangular carrier waveform used in soft-switching PWM inverter will cause difficulties in controlling resonance-trigger time, higher loss in the resonant circuit, and less utilization of the DC bus voltage. If a sawtooth carrier is used in hard-switching PWM inverter, there will be severe distortion in the current waveform. When sawtooth carriers with alternate positive and negative slopes are used in soft-switching PWM inverters, the resonancetrigger time is easy to control, and distortion in the output voltage and current caused by the dead time will not appear.

  7. Numerical optimization of carrier confinement characteristics in (AlxGa1-xN/AlN)SLs/GaN heterostructures

    International Nuclear Information System (INIS)

    We present numerical optimization of carrier confinement characteristics in (AlxGa1-xN/AlN)SLs/GaN heterostructures in the presence of spontaneous and piezoelectrically induced polarization effects. The calculations were made using a self-consistent solution of the Schrödinger, Poisson, potential and charge balance equations. It is found that the sheet carrier density in GaN channel increases nearly linearly with the thickness of AlN although the whole thickness and equivalent Al composition of AlxGa1-xN/AlN superlattices (SLs) barrier are kept constant. This result leads to the carrier confinement capability approaches saturation with thicknesses of AlN greater than 0.6 nm. Furthermore, the influence of carrier concentration distribution on carrier mobility was discussed. Theoretical calculations indicate that the achievement of high sheet carrier density is a trade-off with mobility.

  8. A Novel Minimum Output Variance Estimator for Carrier Frequency Offset in OFDM Systems

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In orthogonal frequency-division multiplexing (OFDM) systems, the carrier frequency offset (CFO)destroys the orthogonality among subcarriers which degrades system performance. Various CFO estimation methods have been developed to compensate for the CFO at the receiver. This paper describes a novel minimum output variance method for OFDM systems with CFO in additive white Gaussian noise channels.This method utilizes the phase and the amplitude of the received signal and reduces the mean square error of the CFO by about 3 dB compared with the original minimum output variance method.

  9. Methanol as an energy carrier

    Energy Technology Data Exchange (ETDEWEB)

    Biedermann, P.; Grube, T.; Hoehlein, B. (eds.)

    2006-07-01

    For the future, a strongly growing energy demand is expected in the transport sector worldwide. Economically efficient oil production will run through a maximum in the next decade. Higher fuel prices and an environmentally desirable reduction of emissions will increase the pressure for reducing fuel consumption and emissions in road traffic. These criteria show the urgent necessity of structural changes in the fuel market. Due to its advantages concerning industrial-scale production, storage and global availability, methanol has the short- to medium-term potential for gaining increased significance as a substitution product in the energy market. Methanol can be produced both from fossil energy sources and from biomass or waste materials through the process steps of synthesis gas generation with subsequent methanol synthesis. Methanol has the potential to be used in an environmentally friendly manner in gasoline/methanol mixtures for flexible fuel vehicles with internal combustion engines and in diesel engines with pure methanol. Furthermore, it can be used in fuel cell vehicles with on-board hydrogen production in direct methanol fuel cell drives, and in stationary systems for electricity and heat generation as well as for hydrogen production. Finally, in portable applications it serves as an energy carrier for electric power generation. In this book, the processes for the production and use of methanol are presented and evaluated, markets and future options are discussed and issues of safety and environmental impacts are addressed by a team of well-known authors. (orig.)

  10. Axial loading verification method for small bones using carrier fringes in speckle pattern interferometry

    Science.gov (United States)

    Dávila, A.; Márquez, S.; Landgrave, E.; Vázquez, Z.; Vera, K.; Caudillo, C.

    2015-06-01

    A computerized system for real-time displacement visualization using carrier fringes in an electronic speckle in-plane sensitive interferometer allows force calibration for micro-displacement analysis of rat bones and verification of axial loading conditions. Once the force has been calibrated and the load is applied along the bone axis, the difference-of-phase method is used to obtain the phase map, which after phase unwrapping, allows the evaluation of the displacements produced by the bone deformation. The proposed method avoids common loading mistakes using first carrier fringes to assure that the loads are within the measuring capabilities of the in-plane interferometer and the Carré phase-stepping method to compensate for linear phase step miscalibration. The experimental results obtained with the calibration of loading forces and axial loading verification show the advantages of the system proposed here over a system which uses a cantilever configuration to make a similar bone deformation analysis.

  11. Optoelectronic characterization of carrier extraction in a hot carrier photovoltaic cell structure

    Science.gov (United States)

    Dimmock, James A. R.; Kauer, Matthias; Smith, Katherine; Liu, Huiyun; Stavrinou, Paul N.; Ekins-Daukes, Nicholas J.

    2016-07-01

    A hot carrier photovoltaic cell requires extraction of electrons on a timescale faster than they can lose energy to the lattice. We optically and optoelectronically characterize two resonant tunneling structures, showing their compatability with hot carrier photovoltaic operation, demonstrating structural and carrier extraction properties necessary for such a device. In particular we use time resolved and temperature dependent photoluminescence to determine extraction timescales and energy levels in the structures and demonstrate fast carrier extraction by tunneling. We also show that such devices are capable of extracting photo-generated electrons at high carrier densities, with an open circuit voltage in excess of 1 V.

  12. Compensations in the Shapley value and the compensation solutions for graph games

    OpenAIRE

    Béal, Sylvain; Rémila, Eric; Solal, Philippe

    2010-01-01

    We consider an alternative expression of the Shapley value that reveals a system of compensations: each player receives an equal share of the worth of each coalition he belongs to, and has to compensate an equal share of the worth of any coalition he does not belong to. We give an interpretation in terms of formation of the grand coalition according to an ordering of the players and define the corresponding compensation vector. Then, we generalize this idea to cooperative games with a communi...

  13. Compensation for forest ecological services in China

    Institute of Scientific and Technical Information of China (English)

    Liu Can; Wang Sen; Zhang Wei; Liang Dan

    2007-01-01

    The paper discusses methods to compensate for the costs incurred in the supply of forest ecological services (FES), i.e.government dominated and market-based instruments as well as progress made so far in China. Factors which constrain the supply of these services and potential policy improvements are presented.

  14. A multiportal compensator system for IMRT delivery

    International Nuclear Information System (INIS)

    We have developed a multiportal compensator system for IMRT delivery, comprising a rotational compensator mount for a linac head, cylindrical compensator enclosures positioned in the mount, a vacuum-formed thermoplastic sheet with heavy alloy granules inside the enclosure, and a vacuum thermoforming device. The mount rotates like a revolver by a stepping motor, thus allowing automatic multiportal IMRT without exchanging compensators by human operators during treatment. The thermoforming device has servo-motor-driven 10x10 metal rod elements to actualize an arbitrary intensity profile. The thermoplastic sheet is preheated by a built-in biplanar heater and then it is placed over the rod elements. Subsequently, vacuum forming is performed through corner cut-outs of the rod elements. After forced cooling down, the heavy alloy granules are fed into the formed sheet. Preliminary experiment using solid water phantoms and an x-ray film has shown that the intensity profile on the film agrees reasonably well with the desired profile

  15. Compensation techniques for operational amplifier bias current

    International Nuclear Information System (INIS)

    Two techniques are proposed for the compensation of the input current on operational amplifiers that can be used on inverting and non-inverting configurations. A qualitative analysis of temperature drift problems is made, and as a practical application, the construction of a voltage follower for high impedance measurements is presented. (Author)

  16. Wavefront compensation applied to AVLIS laser systems

    International Nuclear Information System (INIS)

    The efficiency of an AVLIS system depends upon the power density and uniformity of the laser system. Because of wavefront aberrations the realized beam quality is not ideal. Wavefront compensation provides a means to improve beam quality and system efficiency. (author)

  17. The cost and compensability of trauma patients.

    Science.gov (United States)

    Curtis, Kate; Dickson, Cara; Black, Deborah; Nau, Thomas

    2009-02-01

    Injury in Australia was responsible for 400 000 hospitalisations in 2002. This study aimed to examine the direct costs of trauma patients in a Level 1 trauma centre and determine the compensability of those patients. Data on all admitted patients (206) filling trauma criteria were collected prospectively over a 3-month period (November 2006 to January 2007). A 10-question survey was completed on each patient to record mechanism of injury, third party private health insurance or workers compensation, and direct costs were also obtained. 30% of trauma admissions had an injury severity score (ISS)> 15 (n = 62; median ISS =9; range, 1-56). Median length of stay was 3 days (range, 1-126). Almost half (47%) of the patients were involved in road trauma, and 29% in falls. More than half (53.4%) were eligible for compensation (21.8% of patients had full hospital health insurance cover, 21.4% third party insurance and 9.2% workers compensation). The mechanism of injury with the highest median cost per patient was assault, followed by pedal cyclists, pedestrians then motor vehicle collisions. PMID:19203337

  18. A slow gravity compensated atom laser

    DEFF Research Database (Denmark)

    Kleine Büning, G.; Will, J.; Ertmer, W.;

    2010-01-01

    We report on a slow guided atom laser beam outcoupled from a Bose–Einstein condensate of 87Rb atoms in a hybrid trap. The acceleration of the atom laser beam can be controlled by compensating the gravitational acceleration and we reach residual accelerations as low as 0.0027 g. The outcoupling me...

  19. PRECISELY COMPENSATED EFFICIENT COMPONENT MODE SYNTHESIS METHOD

    Institute of Scientific and Technical Information of China (English)

    Zhu Yutian; Ichiro Hagiwara

    2004-01-01

    Based on the improved mode superposition method proposed by Z.D.Ma and I.Hagiwara, a precisely compensated efficient mode synthesis method is developed.The calculation procedure is discussed in detail and the truncation error is also analyzed.By comparison, it is shown that this method has a higher accuracy and a less calculation time than the general used ones.

  20. On compensation in multidimensional response modeling

    NARCIS (Netherlands)

    Linden, van der W.J.

    2012-01-01

    The issue of compensation in multidimensional response modeling is addressed. We show that multidimensional response models are compensatory in their ability parameters if and only if they are monotone. In addition, a minimal set of assumptions is presented under which the MLEs of the ability parame

  1. Annual compensation for pipelines in Alberta

    International Nuclear Information System (INIS)

    The Surface Rights Board (SRB) in Alberta held a hearing in November 2007 to address three issues involving a pipeline for Enbridge Pipelines (Athabasca) Inc. as well as several land owner issues in Townships 66-68 and Ranges 17-19, all west of the 4th Meridian. The issues the SRB examined were the appropriate amount (i.e. magnitude) of compensation payable under right of entry orders under consideration; the appropriate structure of the compensation award; and to whom the compensation was payable. This document presented a review by the Farmer's Advocate Office (FAO) of the published decision of the SRB. The verbatim decision and rationale used by the SRB to award annual compensation for loss and/or ongoing nuisance and inconvenience was presented. The document could be useful to landowners as they determine their negotiation strategy when faced with considering future pipeline access agreements. The document included a discussion of the context for the decision and a case review. Specific topics that were covered included the rationale for the decision; long term effects of pipeline arguments and SRB commentary; the award and determination; and what still needs to be done. It was concluded that the SRB requires evidence in order to answer several questions regarding the magnitude of any losses, and to what degree, if any, had the nuisance, inconvenience, and loss of rights already been anticipated and factored into the operator's final offer

  2. Dispersion Compensation with a Prism-pair

    CERN Document Server

    Shaked, Yaakov; Pe'er, Avi

    2014-01-01

    We present a detailed calculation of the total dispersion (spectral phase) from a pair of Brewster-cut prisms. This paper aims to aid advanced students in tracking the operation of this major configuration for dispersion-compensation and phase-control of ultra-short pulses.

  3. Filament stretching rheometer: inertia compensation revisited

    DEFF Research Database (Denmark)

    Szabo, Peter; McKinley, Gareth H.

    2003-01-01

    The necessary inertia compensation used in the force balance for the filament stretching rheometer is derived for an arbitrary frame of reference. This enables the force balance to be used to extract correctly the extensional viscosity from measurements of the tensile force at either end of the...

  4. 13 CFR 113.515 - Compensation.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Compensation. 113.515 Section 113.515 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NONDISCRIMINATION IN FINANCIAL... of which requires equal skill, effort, and responsibility, and that are performed under...

  5. Large Capacity SMES for Voltage Dip Compensation

    Science.gov (United States)

    Iwatani, Yu; Saito, Fusao; Ito, Toshinobu; Shimada, Mamoru; Ishida, Satoshi; Shimanuki, Yoshio

    Voltage dips of power grids due to thunderbolts, snow damage, and so on, cause serious damage to production lines of precision instruments, for example, semiconductors. In recent years, in order to solve this problem, uninterruptible power supply systems (UPS) are used. UPS, however, has small capacity, so a great number of UPS are needed in large factories. Therefore, we have manufactured the superconducting magnetic energy storage (SMES) system for voltage dip compensation able to protect loads with large capacity collectively. SMES has advantages such as space conservation, long lifetime and others. In field tests, cooperating with CHUBU Electric Power Co., Inc. we proved that SMES is valuable for compensating voltage dips. Since 2007, 10MVA SMES improved from field test machines has been running in a domestic liquid crystal display plant, and in 2008, it protected plant loads from a number of voltage dips. In this paper, we report the action principle and components of the improved SMES for voltage dip compensation, and examples of waveforms when 10MVA SMES compensated voltage dips.

  6. 7 CFR 301.74-5 - Compensation.

    Science.gov (United States)

    2010-01-01

    ... marketers. Orchard owners eligible for compensation under this paragraph who market all fruit they produce...) Direct marketers. Owners of commercial stone fruit orchards who APHIS has determined meet the eligibility... marketers. The completed application must be accompanied by: (i) A copy of the emergency action...

  7. Concentrating Radioactivity

    Science.gov (United States)

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  8. Active Wireline Heave Compensation for Ocean Drilling

    Science.gov (United States)

    Goldberg, D.; Liu, T.; Swain, K.; Furman, C.; Iturrino, G. J.

    2014-12-01

    The up-and-down heave motion of a ship causes a similar motion on any instruments tethered on wireline cable below it. If the amplitude of this motion is greater than a few tens of cm, significant discrepancy in the depth below the ship is introduced, causing uncertainty in the acquired data. Large and irregular cabled motions also increase the risk of damaging tethered instruments, particularly those with relatively delicate sensors. In 2005, Schlumberger and Deep Down, Inc built an active wireline heave compensator (AHC) system for use onboard the JOIDES Resolution to compensate for heave motion on wireline logging tools deployed in scientific drill holes. The goals for the new AHC system were to (1) design a reliable heave compensation system; and (2) devise a robust and quantitative methodology for routine assessment of compensation efficiency (CE) during wireline operations. Software programs were developed to monitor CE and the dynamics of logging tools in real-time, including system performance under variable parameters such as water depth, sea state, cable length, logging speed and direction. We present the CE results from the AHC system on the JOIDES Resolution during a 5-year period of recent IODP operations and compare the results to those from previous compensation systems deployed during ODP and IODP. Based on new data under heave conditions of ±0.2-2.0 m and water depths of 300-4,800 m in open holes, the system reduces 65-80% of downhole tool displacement under stationary conditions and 50-60% during normal logging operations. Moreover, down/up tool motion at low speeds (300-600 m/h) reduces the system's CE values by 15-20%, and logging down at higher speeds (1,000-1,200 m/h) reduces CE values by 55-65%. Furthermore, the system yields slightly lower CE values of 40-50% without tension feedback of the downhole cable while logging. These results indicate that the new system's compensation efficiency is comparable to or better than previous systems

  9. Kinetics of photo-activated charge carriers in Sn:CdS

    Science.gov (United States)

    Patidar, Manju Mishra; Panda, Richa; Gorli, V. R.; Gangrade, Mohan; Nath, R.; Ganesan, V.

    2016-05-01

    Kinetics of the photo-activated charge carriers has been investigated in Tin substituted Cadmium Sulphide, Cd1-xSnxS (x=0, 0.05, 0.10 and 0.15), thin films prepared by spray pyrolysis. X-Ray Diffraction shows an increase in strain that resulted in the decreased crystallite size upon Sn substitution. At the first sight, the photo current characteristics show a quenching effect on Sn substitution. However, survival of persistent photocurrents is seen even up to 15% of Sn substitution. Transient photo current decay could be explained with a 2τ relaxation model. CdS normally has an n-type character and the Sn doping expected to inject hole carriers. The two fold increase in τ1, increase in activation energy and the decrease in photocurrents upon Sn substitution point towards a band gap cleaning scenario that include compensation and associated carrier injection dynamics. In addition Atomic Force Microscopy shows a drastic change in microstructure that modulates the carrier dynamics as a whole.

  10. CARRIER-FREQUENCY HARMONIZATION STRUCTURE FOR ENHANCED AMPLITUDE MODULATION FUNCTION

    Directory of Open Access Journals (Sweden)

    B.V.Subba Rao

    2013-06-01

    Full Text Available Amplitude Modulation was the major method of influencing sound on a radio signal and is still extensively used in the present days. The characteristic amplitude modulation radio receivers’ automatic gain-control to circumvent bass distortion, generally reacts extreme moreover slowly to average out or overwhelm these intercarrier beat modulations as a result, these extremely aggravating modulation effects are mainly distributed on unbroken to the eavesdropper. A GPS-referenced frequency-synchronizer unit could be organized at transmitter sites capable of holding both current and big transmitters as a result basically eradicating carrier beat interference between co-channel amplitude modulation stations. The beat-related properties are a main aspect in the deprivation of dusk and night-time amplitude modulation fringe-area function excellence and the subsequent damage of hearers for effectively all stations. Commonly, an amplitude modulation radio listener for the duration of the sundown and nightfall hours and to a slighter amount in the first day break, obtains undesired sky wave indications from numerous distant locations as well as the desired local signal. The simple oscillator is naturally a predictable high-stability quartz-crystal kind, temperature compensated. To stand long-term drifts, advanced years effects, and loading-circuit variations, the simple oscillator is somewhat adjusted through electronic or mechanical resources to path a high-precision cause of standard frequency. The steady local reference frequency is then used as a timer for a typical numerically applied frequency synthesizer, which is planned to create the specific receiver carrier frequency expected.

  11. Resource-Efficient Fusion with Pre-Compensated Transmissions for Cooperative Spectrum Sensing

    Directory of Open Access Journals (Sweden)

    Dayan Adionel Guimarães

    2015-05-01

    Full Text Available Recently, a novel fusion scheme for cooperative spectrum sensing was proposed for saving resources in the control channel. Secondary users (SUs simultaneously report their decisions using binary modulations with the same carrier frequencies. The transmitted symbols add incoherently at the fusion centre (FC, leading to a larger set of symbols in which a subset is associated with the presence of the primary user (PU signal, and another subset is associated with the absence of such a signal. The decision criterion applied for discriminating these subsets works under the assumption that the channel gains are known at the FC. In this paper, we propose a new simultaneous transmission and decision scheme in which the task of channel estimation is shifted from the FC to the SUs, without the need for feeding-back of the estimates to the FC. The estimates are used at the SUs to pre-compensate for the reporting channel phase rotations and to partially compensate for the channel gains. This partial compensation is the result of signal clipping for peak-to-average power ratio (PAPR control. We show, analytically and with simulations, that this new scheme can produce large performance improvements, yet reduces the implementation complexity when compared with the original one.

  12. 49 CFR 369.2 - Classification of carriers-motor carriers of property, household goods carriers, and dual...

    Science.gov (United States)

    2010-10-01

    ... operating revenues after applying the revenue deflator formula shown in Note A. (3) When a business combination occurs such as a merger, reorganization, or consolidation, the surviving carrier shall...

  13. High capacity carrier ethernet transport networks

    DEFF Research Database (Denmark)

    Rasmussen, Anders; Zhang, Jiang; Yu, Hao; Fu, Rong; Ruepp, Sarah Renée; Wessing, Henrik; Berger, Michael Stübert

    2009-01-01

    technology, making the use of Ethernet as a convergence layer for Next Generation Networks a distinct possibility. Triple Play services, in particular IPTV, are expected to be a main drivers for carrier Ethernet, however, a number of challenges must be addressed including QoS enabled control plane, enhanced...... OAM functions, survivability and the increased bandwidth requirements of carrier class systems. This article provides an overview of PBB-TE and T-MPLS and demonstrates how IPTV services can be realized in the framework of Carrier Ethernet. In addition we provide a case study on performing bit error...

  14. High capacity carrier ethernet transport networks

    DEFF Research Database (Denmark)

    Rasmussen, Anders; Zhang, Jiang; Yu, Hao;

    2009-01-01

    Ethernet as a transport technology has, up to now, lacked the features such as network layer architecture, customer separation and manageability that carriers require for wide-scale deployment. However, with the advent of PBB-TE and T-MPLS, it is now possible to use Ethernet as a transport...... OAM functions, survivability and the increased bandwidth requirements of carrier class systems. This article provides an overview of PBB-TE and T-MPLS and demonstrates how IPTV services can be realized in the framework of Carrier Ethernet. In addition we provide a case study on performing bit error...

  15. ISRAEL’S NATIONAL WATER CARRIER

    OpenAIRE

    Nathan Cohen

    2008-01-01

    The National Water Carrier of Israel (Ha Movil Ha' Artzi). It is the main water project of Israel and its main task is to transfer water from the rainy north to the center and to the arid south. The National Water Carrier connects the Sea of Galilee with Israel's water system. The original goal was to provide irrigation water to Negev. Today 80% of the water is utilized for Israel's domestic consumption. Most of the water works in Israel are combined with the National Water Carrier for about...

  16. Carrier scattering in metals and semiconductors

    CERN Document Server

    Gantmakher, VF

    1987-01-01

    The transport properties of solids, as well as the many optical phenomena in them are determined by the scattering of current carriers. ``Carrier Scattering in Metals and Semiconductors'' elucidates the state of the art in the research on the scattering mechanisms for current carriers in metals and semiconductors and describes experiments in which these mechanisms are most dramatically manifested.The selection and organization of the material is in a form to prepare the reader to reason independently and to deal just as independently with available theoretical results and experimental

  17. Compensation of errors in robot machining with a parallel 3D-piezo compensation mechanism

    OpenAIRE

    Schneider, Ulrich; Drust, Manuel; Puzik, Arnold; Verl, Alexander

    2013-01-01

    This paper proposes an approach for a 3D-Piezo Compensation Mechanism unit that is capable of fast and accurate adaption of the spindle position to enhance machining by robots. The mechanical design is explained which focuses on low mass, good stiffness and high bandwidth in order to allow compensating for errors beyond the bandwidth of the robot. In addition to previous works [7] and [9], an advanced actuation design is presented enabling movements in three translational axes allowing a work...

  18. Re-Planning for Compensator-Based IMRT with Original Compensators

    International Nuclear Information System (INIS)

    Compared with multileaf collimator (MLC)-based intensity-modulated radiotherapy (IMRT) for moving targets, compensator-based IMRT has advantages such as shorter beam-on time, fewer monitor units with potentially decreased secondary carcinogenesis risk, better optimization-to-deliverable dose conversion, and often better dose conformity. Some of the disadvantages include additional time for the compensators to be built and delivered, as well as extra cost. Patients undergoing treatment of abdominal cancers often experience weight loss. It would be necessary to account for this change in weight with a new plan and a second set of compensators. However, this would result in treatment delays and added costs. We have developed a method to re-plan the patient using the same set of compensators. Because the weight changes seen with the treatment of abdominal cancers are usually relatively small, a new 4D computed tomography (CT) acquired in the treatment position with markers on the original isocenter tattoos can be registered to the original planning scan. The contours of target volumes from the original scans are copied to the new scan after fusion. The original compensator set can be used together with a few field-in-field (FiF) beams defined by the MLC (or beams with cerrobend blocks for accelerators not equipped with a MLC). The weights of the beams with compensators are reduced so that the FiF or blocked beams can be optimized to mirror the original plan and dose distribution. Seven abdominal cancer cases are presented using this technique. The new plan on the new planning CT images usually has the same dosimetric quality as the original. The target coverage and dose uniformity are improved compared with the plan without FiF/block modification. Techniques combining additional FiF or blocked beams with the original compensators optimize the treatment plans when patients lose weight and save time and cost compared with generating plans with a new set of compensators.

  19. Deformation compensation in dynamic tomography; Compensation de deformations en tomographie dynamique

    Energy Technology Data Exchange (ETDEWEB)

    Desbat, L. [Universite Joseph Fourier, UMR CNRS 5525, 38 - Grenoble (France); Roux, S. [Universite Joseph Fourier, TIMC-IMAG, In3S, Faculte de Medecine, 38 - Grenoble (France)]|[CEA Grenoble, Lab. d' Electronique et de Technologie de l' Informatique (LETI), 38 (France); Grangeat, P. [CEA Grenoble, Lab. d' Electronique et de Technologie de l' Informatique (LETI), 38 (France)

    2005-07-01

    This work is a contribution to the compensation of motion in tomography. New classes of deformation are proposed, that compensates analytically by an algorithm of a F.B.P. type reconstruction. This work makes a generalisation of the known results for affine deformations, in parallel geometry and fan-beam, to deformation classes of infinite dimension able to include strong non linearities. (N.C.)

  20. Dosimetric evaluation of compensation in radiotherapy of the breast: MLC intensity modulation and physical compensators

    International Nuclear Information System (INIS)

    Background and purpose: Electronic portal images may be used to design the compensation required to maximise dose uniformity in the breast from opposed tangential beams. Materials and methods: Four methods of implementing the desired compensation have been studied: a simple wedge, a physical compensator in conjunction with a wedge; one open field plus four shaped multi-leaf-collimated (MLC) fields, and one wedged field in conjunction with three shaped MLC fields. Evaluation was performed using thermoluminescent dosimeters (TLDs) placed inside a phantom which was designed to mimic the human breast. The measured results are compared with both the prediction of the in-house compensation design software and with the dose predicted by the GE Target II planning system. The implications of each method for the time taken to plan and deliver treatment were analysed. Results: The dose inhomogeneity, as measured at seven points in the central plane was greatest for the simple wedge (root mean square (rms) = 4.5%) compared to an open field plus four shaped MLC fields (rms = 2.2%), a wedged field plus three shaped MLC fields (rms = 3.3%), and the physical compensator (rms = 2.4%). The times required to plan and prepare these treatments varied considerably. The standard wedged treatment required under 15 min; both MLC-based and the physical compensator treatments required = 50 min. Differences of treatment delivery times were up to 8 min. Conclusions: These results indicate that the dose inhomogeneity can be reduced by beam intensity modulation designed using EPIDs

  1. Method for Analysis of an Offshore Heave Compensator

    Directory of Open Access Journals (Sweden)

    Gwi-Nam Kim

    2016-02-01

    Full Text Available A heave compensation system consists of a drill string compensator (DSC and an active heave compensator (AHC cylinder, which together produce control force over an oil pressure system suitable for transmission of considerable power and compensating for heaving motion of the hull during drilling work. In this study, a heave compensator of an oil pressure system was simulated to draw a conclusion, which was verified by comparison with the result of a test conducted using an actual miniature model. The compensation rate was 95%, based on which the dynamic behaviors of an actual-size heave compensator were presumed. Furthermore, the speed of each cylinder and the acceleration of heave can be determined and used to fabricate an actual-size heave compensator.

  2. 48 CFR 970.2803-1 - Workers' Compensation Insurance.

    Science.gov (United States)

    2010-10-01

    ... SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS Bonds and Insurance 970.2803-1 Workers... apply where management and operating contractors purchase workers' compensation insurance. With respect... workers' compensation insurance programs of management and operating contractors in the light...

  3. MTB-USDH Compensation Tracking System (MTB-CTS)

    Data.gov (United States)

    US Agency for International Development — MTB-USDH Compensation Tracking System: is the USDH Compensation Tracking System (MTB-CTS) to assist managers in monitoring their payroll costs for U.S. direct...

  4. Laser interferometric method for determining the carrier diffusion length in semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Manukhov, V. V. [Saint Petersburg State University (Russian Federation); Fedortsov, A. B.; Ivanov, A. S., E-mail: ivaleks58@gmail.com [Saint Petersburg Mining University (Russian Federation)

    2015-09-15

    A new laser interferometric method for measuring the carrier diffusion length in semiconductors is proposed. The method is based on the interference–absorption interaction of two laser radiations in a semiconductor. Injected radiation generates additional carriers in a semiconductor, which causes a change in the material’s optical constants and modulation of the probing radiation passed through the sample. When changing the distance between carrier generation and probing points, a decrease in the carrier concentration, which depends on the diffusion length, is recorded. The diffusion length is determined by comparing the experimental and theoretical dependences of the probe signal on the divergence of the injector and probe beams. The method is successfully tested on semiconductor samples with different thicknesses and surface states and can be used in scientific research and the electronics industry.

  5. In vivo evaluation of a simvastatin-loaded nanostructured lipid carrier for bone tissue regeneration

    Science.gov (United States)

    Yue, Xinxin; Niu, Mao; Zhang, Te; Wang, Cheng; Wang, Zhonglei; Wu, Wangxi; Zhang, Qi; Lai, Chunhua; Zhou, Lei

    2016-03-01

    Alveolar bone loss has long been a challenge in clinical dental implant therapy. Simvastatin (SV) has been demonstrated to exert excellent anabolic effects on bone. However, the successful use of SV to increase bone formation in vivo largely depends on the local concentration of SV at the site of action, and there have been continuing efforts to develop an appropriate delivery system. Specifically, nanostructured lipid carrier (NLC) systems have become a popular type of encapsulation carrier system. Therefore, SV-loaded NLCs (SNs) (179.4 nm in diameter) were fabricated in this study, and the osteogenic effect of the SNs was evaluated in a critical-sized rabbit calvarial defect. Our results revealed that the SNs significantly enhanced bone formation in vivo, as evaluated by hematoxylin and eosin (HE) staining, immunohistochemistry, and a fluorescence analysis. Thus, this novel nanostructured carrier system could be a potential encapsulation carrier system for SV in bone regeneration applications.

  6. A novel approach to investigate bulk carrier lifetime using low frequency fluctuation noise measurement

    International Nuclear Information System (INIS)

    The carrier lifetime of silicon wafer-based solar cells is measured by a newly proposed novel approach—inference from low frequency noise (1/f) fluctuations. Our derived carrier lifetime calculation formula conforms well to standard 1/f behavior, which mathematically validates our model. Without a priori information about the material parameters e.g. dopant concentration etc, 1/f noise measurement is able to conclude the average carrier lifetime with accuracy comparable to conventional quasi steady state optical methods. The carrier lifetime model is potentially beneficial in characterizing bulk-state solar cells and can be extended further to the packaged devices where the pulse light decay signal measurement is difficult. (paper)

  7. Laser interferometric method for determining the carrier diffusion length in semiconductors

    International Nuclear Information System (INIS)

    A new laser interferometric method for measuring the carrier diffusion length in semiconductors is proposed. The method is based on the interference–absorption interaction of two laser radiations in a semiconductor. Injected radiation generates additional carriers in a semiconductor, which causes a change in the material’s optical constants and modulation of the probing radiation passed through the sample. When changing the distance between carrier generation and probing points, a decrease in the carrier concentration, which depends on the diffusion length, is recorded. The diffusion length is determined by comparing the experimental and theoretical dependences of the probe signal on the divergence of the injector and probe beams. The method is successfully tested on semiconductor samples with different thicknesses and surface states and can be used in scientific research and the electronics industry

  8. Carrier Density Dependence of sp-d Exchange in Nanostructured ZnO:Mn Thin Film

    Directory of Open Access Journals (Sweden)

    Ebrahimizadeh Abrishami M.

    2012-08-01

    Full Text Available In this work, the nanostructured ZnO:Mn thin films with different Mn concentration (5, 10 and 15 mol% have been grown on glass substrates at 500°C by the spray pyrolysis technique. The average grain size was estimated about 25 nm using SEM micrographs. The Faraday rotations were determined in applied magnetic fields up to 1.05 T. The highest values of Faraday rotation were observed in the sample with 5 mol% Mn concentration. The carrier density has been calculated from the Faraday rotations and it is observed that the sp-d exchange in magnetic semiconductor is strongly affected by carrier parameters

  9. Fullerenes: A New Carrier Phase for Noble Gases in Meteorites

    Science.gov (United States)

    Becker, Luann

    2004-01-01

    The major focus of our research effort has been to measure the noble gases encapsulated within fullerenes, a new carbon carrier phase and compare it to the myriad of components found in the bulk meteorite acid residues. We have concentrated on the carbonaceous chondrites (Allende, Murchison and Tagish Lake) since they have abundant noble gases, typically with a planetary signature that dominates the stepped-release of the meteorite bulk acid residue. They also contain an extractable fullerene component that can be isolated and purified from the same bulk material.

  10. The economic consequences of executive compensation disclosure: evidence from Germany

    OpenAIRE

    Lofruthe, Hendrik

    2011-01-01

    PURPOSE OF THE STUDY Executive compensation frequently makes headlines in both academic journals and the yellow press. From the academic point of view, executive compensation has its grounds in agency theory. Effective compensation schemes align the interests of managers and owners and motivate managers to maximize shareholder value. Disclosure of compensation schemes enables shareholders to evaluate the remuneration contracts’ adequacy. In 2005, the German legislator created a natural exp...

  11. A General Theoretical Model of Enthalpy-EntropyCompensation

    Institute of Scientific and Technical Information of China (English)

    LIU,Lei; GUO, Qing-Xiang

    2001-01-01

    Enthalpy-entropy compensation remains a mystery in chemistry and biophysics.recent study suggested that the solventreorganization might constitute the physical orihin of the compensation, which was unforumstely not wisely applicable because compensation was also observeserved in solid phade reactions.In this study,a general theoretical model based upon strictmathematical deduction was presented,which indicated thatthe redistribution of the distinguishable subspecies might bethe physical origin of the enthalpy-intropy compensations in solvation and surface adsorption weue discussed.

  12. Design and prototype of Variable Gravity Compensation Mechanism (VGCM)

    OpenAIRE

    Takesue, Naoyuki; Ikematsu, Takashi; Murayama, Hideyuki; Fujimoto, Hideo

    2011-01-01

    A machine moving vertically requires strong gravitational resistance. Gravity compensation mechanisms devised to reduce actuator force mostly compensate for constant weight, but practical use requires that the mechanism compensate for weight variations. This paper presents a Variable Gravity Compensation Mechanism (VGCM) that uses two types of linear springs and changes the equilibrium position of one. The mechanism principle is described and the prototype is designed. Performance is experime...

  13. Work-Related Musculoskeletal Diseases and the Workers' Compensation

    OpenAIRE

    Jang, Tae-Won; KOO, Jung-Wan; Kwon, Soon-Chan; Song, Jaechul

    2014-01-01

    The Industrial Accident Compensation Insurance Act (IACIA) regulates the workers' compensation insurance system and the standards for the recognition of occupational diseases (ODs). Since its establishment in 1994, the IACIA has been amended several times. Before 2008, the approval of compensation for work-related musculoskeletal diseases (WMSDs) was decided based on the recommendation of consultants of the Korea Workers' Compensation and Welfare Service (COMWEL). The IACIA was amended in 200...

  14. Sales compensation governance: the last frontier of corporate reform.

    Science.gov (United States)

    Gundy, Peter R; Gaeta, Elizabeth C

    2004-01-01

    The area of sales compensation has remained relatively untouched by recent pressures for compensation reform. This article highlights some of the ways that sales organizations stumble in managing their compensation programs, and why it takes more than a simple tactical fix to address these problems effectively. The authors describe a more structured governance framework that not only identifies and resolves key sales compensation issues, but ultimately safeguards the effectiveness and financial integrity of the sales organization itself. PMID:15015424

  15. Video Coding with Motion-Compensated Lifted Wavelet Transforms

    OpenAIRE

    Flierl, M; Girod, B.

    2004-01-01

    This article explores the efficiency of motion-compensated three-dimensional transform coding, a compression scheme that employs a motion-compensated transform for a group of pictures. We investigate this coding scheme experimentally and theoretically. The practical coding scheme employs in temporal direction a wavelet decomposition with motion-compensated lifting steps. Further, we compare the experimental results to that of a predictive video codec with single-hypothesis motion compensation...

  16. Clusters of dislocations in a carrier wave

    International Nuclear Information System (INIS)

    Clusters of point dislocations (wave vortices) may be present within an otherwise perfect plane scalar wave, a carrier wave in two dimensions, which may be evanescent. The question arises: is it possible to deduce the orientation of the distant undisturbed carrier wave purely from local information about the cluster itself? For groups of two and four dislocations in a carrier wave, this may be done by using no other information than the local phase map or the individual positions of the singularities. The maximum number possible in a cluster with a carrier wave is 4 and the total strength (topological charge) of a cluster is always zero or ± 2. The study includes an examination of degenerate dislocations of strength zero or ± 1

  17. The Kinetics of Carrier Transport Inhibition

    DEFF Research Database (Denmark)

    Rosenberg, T.; Wilbrandt, Robert Walter

    1962-01-01

    The kinetical treatment of enzymatic carrier transports as given in previous communications has been extended to conditions of inhibition. Various possible types of inhibitors have been considered differing in the site of attack (enzyme or carrier), in the mode of action (competing with the...... substrate for the enzyme or the carrier or for both, competing with the carrier for the enzyme, or non-competitive) and in the ability of penetrating the membrane. Experiments are reported on the inhibition of glucose and fructose transport across the human red cell membrane by phlorizine, phloretine and......, with the result that a certain asymmetry of inhibition (stronger inhibition of exit than of entrance) is to be expected. This asymmetry was termed “first order asymmetry”. In experiments with each of the three inhibitors an asymmetry of inhibition in the expected direction was observed which however...

  18. Physician Fee Schedule Carrier Specific Files

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Centers for Medicare and Medicaid Services (CMS) has condensed all 56 Physician Fee Schedule (PFS) carrier specific pricing files into one zip file. It is...

  19. Intraoral radiation carrier for edentulous patients

    International Nuclear Information System (INIS)

    The principles of fabricating an intraoral radioactive carrier have been described to treat malignant diseases of the oral cavity. The prosthesis provides consistent direction and fixation of the radioactive source into the same location

  20. Intraoral radiation carrier for edentulous patients

    Energy Technology Data Exchange (ETDEWEB)

    Sela, M.; Taicher, S.

    1983-12-01

    The principles of fabricating an intraoral radioactive carrier have been described to treat malignant diseases of the oral cavity. The prosthesis provides consistent direction and fixation of the radioactive source into the same location.

  1. Protection switching for carrier ethernet multicast

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Wessing, Henrik; Berger, Michael Stübert

    2010-01-01

    This paper addresses network survivability for IPTV multicast transport in Carrier Ethernet networks. The impact of link failures is investigated and suggestions for intelligent multicast resilience schemes are proposed. In particular, functions of the multicast tree are integrated with the Carrier...... recovery path length, recovery time, number of branch nodes and operational complexity. The integrated approach therefore shows significant potential to increase the QoE for IPTV users in case of network failures and recovery actions....

  2. Airport Congestion When Carriers Have Market Power

    OpenAIRE

    Brueckner, Jan K.

    2002-01-01

    This paper analyzes airport congestion when carriers are nonatomistic, showing how the results of the road-pricing literature are modified when the economic agents causing congestion have market power. The analysis shows that when an airport is dominated by a monopolist, congestion is fully internalized, yielding no role for congestion pricing under monopoly conditions. Under a Cournot oligopoly, however, carriers are shown to internalize only the congestion they impose on themselves. A toll ...

  3. Evaluating multicast resilience in carrier ethernet

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Wessing, Henrik; Zhang, Jiang;

    2010-01-01

    This paper gives an overview of the Carrier Ethernet technology with specific focus on resilience. In particular, we show how multicast traffic, which is essential for IPTV can be protected. We detail the ackground for resilience mechanisms and their control and e present Carrier Ethernet...... resilience methods for linear nd ring networks. By simulation we show that the vailability of a multicast connection can be significantly increased by applying protection methods....

  4. Preparation and application of magnetic microsphere carriers

    Institute of Scientific and Technical Information of China (English)

    ZHANG Bo; XING Jianmin; LIU Huizhou

    2007-01-01

    Magnetic microsphere carriers have received considerable attention,primarily because of their wide applications in the fields of biomedicine and bioengineering.In this paper,preparation methods,surface modification and application of magnetic carriers are reviewed.Emphasis will be placed on recent biological and biomedical developments and trends such as enzyme immobilization,cell isolation,protein purification,target drugs and DNA separation.

  5. 26 CFR 1.85-1 - Unemployment compensation.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Unemployment compensation. 1.85-1 Section 1.85-1...) INCOME TAXES (CONTINUED) Items Specifically Included in Gross Income § 1.85-1 Unemployment compensation... unemployment compensation (as defined in paragraph (b)(1) of this section) paid in taxable years...

  6. 45 CFR 302.65 - Withholding of unemployment compensation.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false Withholding of unemployment compensation. 302.65... HUMAN SERVICES STATE PLAN REQUIREMENTS § 302.65 Withholding of unemployment compensation. The State plan... State agency charged with the administration of the State unemployment compensation laws in...

  7. 12 CFR 918.2 - Annual directors' compensation policy.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Annual directors' compensation policy. 918.2... HOME LOAN BANKS BANK DIRECTOR COMPENSATION AND EXPENSES § 918.2 Annual directors' compensation policy. Beginning in 2000 and annually thereafter, each Bank's board of directors shall adopt by resolution...

  8. 38 CFR 3.701 - Elections of pension or compensation.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Elections of pension or compensation. 3.701 Section 3.701 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS ADJUDICATION Pension, Compensation, and Dependency and Indemnity Compensation Concurrent Benefits and...

  9. 20 CFR 211.15 - Verification of compensation claimed.

    Science.gov (United States)

    2010-04-01

    ... employee, which is not credited in the records of the Board, must be verified to the satisfaction of the Board before it may be credited. An employee's claim to compensation not credited shall be processed as... employee that the compensation claimed is not creditable. (b) If the compensation is claimed within...

  10. 29 CFR 553.221 - Compensable hours of work.

    Science.gov (United States)

    2010-07-01

    ... Compensable hours of work. (a) The general rules on compensable hours of work are set forth in 29 CFR part 785... 29 Labor 3 2010-07-01 2010-07-01 false Compensable hours of work. 553.221 Section 553.221 Labor... OF THE FAIR LABOR STANDARDS ACT TO EMPLOYEES OF STATE AND LOCAL GOVERNMENTS Fire Protection and...

  11. Executive Compensation and Financial Performance in the Real Estate Industry

    OpenAIRE

    Davis, Barbara J.; Roger M. Shelor

    1995-01-01

    The purpose of this study is to examine the relationships between financial performance, firm size, and executive compensation among firms in the real estate industry. Previous analyses of compensation have not been industry specific. The findings indicate that there is a significant relationship between executive compensation and measures of financial performance, firm size, and age of the highest paid executive.

  12. 29 CFR 541.601 - Highly compensated employees.

    Science.gov (United States)

    2010-07-01

    ... Salary Requirements § 541.601 Highly compensated employees. (a) An employee with total annual... compensation” must include at least $455 per week paid on a salary or fee basis. Total annual compensation may... total annual compensation does not total at least the minimum amount established in paragraph (a)...

  13. 31 CFR 30.0 - Executive compensation and corporate governance.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Executive compensation and corporate governance. 30.0 Section 30.0 Money and Finance: Treasury Office of the Secretary of the Treasury TARP STANDARDS FOR COMPENSATION AND CORPORATE GOVERNANCE § 30.0 Executive compensation and corporate...

  14. 10 CFR 39.53 - Energy compensation source.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Energy compensation source. 39.53 Section 39.53 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Equipment § 39.53 Energy compensation source. The licensee may use an energy compensation source (ECS) which...

  15. 39 CFR 3050.27 - Workers' Compensation Report.

    Science.gov (United States)

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Workers' Compensation Report. 3050.27 Section 3050.27 Postal Service POSTAL REGULATORY COMMISSION PERSONNEL PERIODIC REPORTING § 3050.27 Workers' Compensation Report. The Workers' Compensation Report, including summary workpapers, shall be provided by...

  16. Temperature compensation of resonant cavities with a teflon post

    OpenAIRE

    Bará Temes, Francisco Javier

    1982-01-01

    The negative temperature coefficient of E for teflon is used to compensate the frequency drift of a metal cavity due to thermal expansion. An experimental X-band transmission resonator was compensated in this way with a 10 mm teflon post. The results are considered of great interest for the compensation of waveguide millimiter wave oscillators. Peer Reviewed

  17. Load positioning system with gravity compensation

    Science.gov (United States)

    Hollow, R. H.

    1984-01-01

    A load positioning system with gravity compensation has a servomotor, position sensing feedback potentiometer and velocity sensing tachometer in a conventional closed loop servo arrangement to cause a lead screw and a ball nut to vertically position a load. Gravity compensating components comprise the DC motor, gears, which couple torque from the motor to the lead screw, and constant current power supply. The constant weight of the load applied to the lead screw via the ball nut tend to cause the lead screw to rotate, the constant torque of which is opposed by the constant torque produced by the motor when fed from the constant current source. The constant current is preset as required by the potentiometer to effect equilibration of the load which thereby enables the positioning servomotor to see the load as weightless under both static and dynamic conditions. Positioning acceleration and velocity performance are therefore symmetrical.

  18. Intonation and Compensation of Fretted String Instruments

    CERN Document Server

    Varieschi, Gabriele U

    2009-01-01

    In this paper we present mathematical models and we analyze the physics related to the problem of intonation of musical instruments such as guitars, mandolins and similar, i.e., we study how to produce perfectly in tune notes on these instruments. This analysis begins with the correct fret placement on the instrument fingerboard, following precise mathematical laws, but then it becomes increasingly complicated due to the geometrical deformation of the strings when these instruments are played, and also due to the inharmonic characteristics of the same strings. As a consequence of these factors, perfect intonation of all the notes on the instrument can never be achieved, but complex compensation procedures are introduced and studied to minimize the problem. To test the validity of these compensation procedures, we have performed extensive measurements using standard monochord sonometers and other basic acoustical devices, which confirm the correctness of our theoretical models. In particular, these experimenta...

  19. Vibration Compensation for Scanning Tunneling Microscope

    Institute of Scientific and Technical Information of China (English)

    LI Meng-chao; FU Xing; WEI Xiao-lei; HU Xiao-tang

    2003-01-01

    The influence of vibration is already one of main obstacles for improving the nano measuring accuracy.The techniques of anti-vibration,vibration isolation and vibration compensation become an important branch in nano measuring field.Starting with the research of sensitivity to vibration of scanning tunneling microscope(STM),the theory,techniques and realization methods of nano vibration sensor based on tunnel effect are initially investigated,followed by developing the experimental devices.The experiments of the vibration detection and vibration compensation are carried out.The experimental results show that vibration sensor based on tunnel effect is characterized by high sensitivity,good frequency characteristic and the same vibratory response characteristic consistent with STM.

  20. Aberration compensation in charged particle projection lithography

    International Nuclear Information System (INIS)

    Projection systems offer the opportunity to increase the throughput for charged particle lithography, because such systems image a large area of a mask directly on to a wafer as a single shot. Shots have to be imaged over a certain range of off-axis distances at the wafer to increase the writing speed, because shot sizes are limited to about 0.25x0.25 mm2 due to aberrations. In a projection system with only lenses, however, the aberrations for off-axis shots are still very large, and some aberration compensation elements need to be introduced. In this paper, three aberration compensation elements (deflectors, stigmators and dynamic focus lenses) are first discussed, a suite of newly developed software, called PROJECTION, based on this principle and our unified aberration theory is then described, and an illustrative example computed with the software is finally given

  1. Lossless Compression of Video using Motion Compensation

    OpenAIRE

    Martins, Bo; Forchhammer, Søren

    1998-01-01

    Summary form only given. We investigate lossless coding of video using predictive coding and motion compensation. The new coding methods combine state-of-the-art lossless techniques as JPEG (context based prediction and bias cancellation, Golomb coding), with high resolution motion field estimation, 3D predictors, prediction using one or multiple (k) previous images, predictor dependent error modelling, and selection of motion field by code length. We treat the problem of precision of the mot...

  2. REACTIVE POWER COMPENSATION IN ASYNCHRONOUS ELECTRIC DRIVES

    Directory of Open Access Journals (Sweden)

    V.S. Malyar

    2013-10-01

    Full Text Available A problem of calculating capacity of cosine capacitors for individual compensation of reactive power in asynchronous electric drives in stationary and transient operation modes is considered. The algorithm introduced employs a high-adequacy mathematical model of asynchronous motor developed on the theory of representing vectors which takes into account both the magnetic core saturation and the current displacement in the rotor bars.

  3. Power Compensation for ICRF Heating in EAST

    Science.gov (United States)

    Chen, Gen; Qin, Chengming; Mao, Yuzhou; Zhao, Yanping; Yuan, Shuai; Zhang, Xinjun

    2016-08-01

    The source system covering a working frequency range of 24 MHz to 70 MHz with a total maximum output power of 12 MW has already been fabricated for Ion Cyclotron Range of Frequency (ICRF) heating in EAST from 2012. There are two continuous wave (CW) antennas consisting of four launching elements each fed by a separate 1.5 MW transmitter. Due to the strong mutual coupling among the launching elements, the injection power for launching elements should be imbalance to keep the k‖ (parallel wave number) spectrum of the launcher symmetric for ICRF heating. Cross power induced by the mutual coupling will also induce many significant issues, such as an uncontrollable phase of currents in launching elements, high voltage standing wave ratio (VSWR), and impedance mismatching. It is necessary to develop a power compensation system for antennas to keep the power balance between the feed points. The power balance system consists of two significant parts: a decoupler and phase control. The decoupler helps to achieve ports isolation to make the differential phase controllable and compensate partly cross power. After that, the differential phase of 0 or π will keep the power balance of two feed points completely. The first power compensation system consisting of four decouplers was assembled and tested for the port B antenna at the working frequency of 35 MHz. With the application of the power compensation system, the power balance, phase feedback control, and voltage standing wave ratio (VSWR) had obviously been improved in the 2015 EAST campaign. supported by the National Magnetic Confinement Fusion Science Program of China (No. 2015GB101001) and National Natural Science Foundation of China (Nos. 11575237, 11375235, 11375236)

  4. Board Independence, CEO Pay, and Camouflaged Compensation

    OpenAIRE

    Ruiz-Verdú, Pablo; Singh, Ravi

    2014-01-01

    We study how directors' reputational concerns influence executive compensation and the use ofcamouflaged forms of pay. We show that, in order to signal their independence to investors,boards lower managers' pay, but may also pay managers in hidden ways or structure compensationinefficiently. We also show that independent boards are more likely to make use of hiddencompensation than manager-friendly boards. We apply our model to study the costs and benefitsof greater pay transparency and of me...

  5. Board Committees, CEO Compensation, and Earnings Management

    OpenAIRE

    Laux, Christian; Laux, Volker

    2007-01-01

    We analyze the effect of committee formation on how corporate boards perform two main functions: setting CEO pay and overseeing the financial reporting process. The use of performance-based pay schemes induces the CEO to manipulate earnings, which leads to an increased need for board oversight. If the whole board is responsible for both functions, it is inclined to provide the CEO with a compensation scheme that is relatively insensitive to performance in order to reduce the burden of subsequ...

  6. Motion compensation of Synthetic Aperture Radar

    OpenAIRE

    Duncan, David; Long, David

    2003-01-01

    Synthetic aperture radar (SAR) is a digital signal processing technique which enhances the azimuth resolution of a radar image using the target doppler history created by the motion of the radar platform. If the platform deviates from a constant velocity, straight-line path then image quality is lost and image details become unfocused. Motion compensation (MOCO) is a technique in which the position and attitude of the platform is recorded or estimated and then used to correct the scene's dopp...

  7. Passive heave compensation of heavy modules

    OpenAIRE

    Jakobsen, Sten Magne Eng

    2008-01-01

    New subsea technology has increased size and weight of installed modules significantly. This thesis looks at heavy module installation from barge, through moonpool with use of passive heave compensation. An installation barge is designed with moonpool used as working platform for installation. Motion responses for barge are analyzed with use of marine engineering software MOSES. Responses found shows a significantly impact from moonpool, and it doubtingly if software is capa...

  8. Managerial Compensation Schemes with Informed Principals

    OpenAIRE

    Thomas von Ungern-Sternberg

    2000-01-01

    We study managerial compensation schemes for situations, where the current management knows more about the company's expected profitability than the new employee. When a manager is offered a contract with only a low fixed salary but a high profit participation, he is afraid that the company's profit outlook may be quite bad. Employers are aware of this. In equilibrium high profit employers offer their new managers high fixed salaries and low profit participations. They thereby credibly signal...

  9. Outline of amendments to nuclear compensation law

    International Nuclear Information System (INIS)

    Amendments to 'the Japanese Law on Compensation for Nuclear Damage', submitted to the Diet in February, 1989, were approved as drafted as from January 1st, 1990. Although the Revised Law requires a nuclear operator to raise its financial security amount from 10 to 30 Billion yen, the framework of the Law remains, in principle, unchanged. How we should deal with cross frontier nuclear incidents is an important problem to be studied hereafter. (author)

  10. Spray controller for horizontal boom movements compensation

    OpenAIRE

    El Bahir, Loussain; Lebeau, Frédéric; Destain, Marie-France; Kinnaert; Hanus, Raymond

    2002-01-01

    Longitudinal spray distribution is mainly affected by the horizontal speed variations of the nozzles. Manufacturers classically try to reduce unwanted nozzles movements using horizontal boom suspension but these methods show performance and price limitations. The purpose of this paper is to propose a spray controller aiming to compensate the effect of the horizontal boom movements on the spray distribution besides the effect of tractor speed variations. The controller is based on ...

  11. Concentration of uncompensated impurities as a key parameter of CdTe and CdZnTe crystals for Schottky diode x/γ-ray detectors

    International Nuclear Information System (INIS)

    In this paper we report on the strong impact of the concentration of uncompensated impurities on the detection efficiency of CdTe and Cd0.9Zn0.1Te Schottky diodes. The results of our study explain the observed poor detection properties of some Cd0.9Zn0.1Te detectors with resistivity and lifetime of carriers comparable to those of good CdTe detectors. We show that the concentration of uncompensated impurities in a highly efficient CdTe Schottky diode detector is several orders of magnitude higher than that of a CdZnTe, which does not register the gamma spectra of commonly used isotopes (59–662 keV) by using photoelectric measurements. The significant difference of the concentration of uncompensated impurities between CdTe and Cd0.9Zn0.1Te crystals is confirmed by our study of the temperature change of the resistivity and of the Fermi level energy. The degree of compensation of the donor complex, responsible for the electrical conductivity of the material, is much lower in the CdTe crystal compared to that in the Cd0.9Zn0.1Te crystal. The calculations of the detection efficiency of x/γ-radiation by a Schottky diode result in a dependence on the concentration of uncompensated impurities described by a curve with a pronounced maximum. The position of this maximum occurs at a concentration of uncompensated impurities which ranges from 3 × 1010 to 3 × 1012 cm−3 depending on the registered photon energy of x/γ-rays and on the lifetime of the charge carriers. Our measurements and calculations lead to the conclusion that the concentration of uncompensated impurities in this range is a necessary condition for the effective operation of x- and γ-ray Schottky diode detectors based on CdTe and Cd1−xZnxTe crystals

  12. Sub-diffraction imaging with compensating bilayers

    International Nuclear Information System (INIS)

    We derive a general expression for the material properties of a compensating bilayer, which is a pair of material layers which transfer the field distribution from one side of the bilayer to the other with resolution limited only by the deviation of the material properties from specified values. One of the layers can be free space, a special case of which is the perfect lens, but the layers need not have equal thickness. Compensating a thick layer of free space with a thin layer creates a focusing device with increased working distance, and employs an anisotropic material. It is also possible to achieve compensation of materials with property tensors that are neither positive nor negative definite. In this case, we refer to such media as indefinite, and we analyse, in detail, bilayers of these media which support coupling of internal propagating waves to incident waves of any transverse wave vector. In this case, we find that the enhanced spatial resolution provided by large transverse wave vectors is far less sensitive to loss than that of the perfect lens

  13. Robust, Error-Tolerant Photometric Projector Compensation.

    Science.gov (United States)

    Grundhöfer, Anselm; Iwai, Daisuke

    2015-12-01

    We propose a novel error tolerant optimization approach to generate a high-quality photometric compensated projection. The application of a non-linear color mapping function does not require radiometric pre-calibration of cameras or projectors. This characteristic improves the compensation quality compared with related linear methods if this approach is used with devices that apply complex color processing, such as single-chip digital light processing projectors. Our approach consists of a sparse sampling of the projector's color gamut and non-linear scattered data interpolation to generate the per-pixel mapping from the projector to camera colors in real time. To avoid out-of-gamut artifacts, the input image's luminance is automatically adjusted locally in an optional offline optimization step that maximizes the achievable contrast while preserving smooth input gradients without significant clipping errors. To minimize the appearance of color artifacts at high-frequency reflectance changes of the surface due to usually unavoidable slight projector vibrations and movement (drift), we show that a drift measurement and analysis step, when combined with per-pixel compensation image optimization, significantly decreases the visibility of such artifacts. PMID:26390454

  14. Installation of the sag compensator for HANARO

    International Nuclear Information System (INIS)

    Electric power is essential for all industrial plants and also for nuclear facilities. HANARO is a research reactor which produces a 30MW thermal power. HANARO is designed to be tripped automatically when interruptions or some extents of sags occur. HANARO has the reactor regulation system (RRS) and reactor protection system (RPS). HANARO is designed so as to tripped automatically by insertion of control absorber rods (CAR) and shut-off rods (SOR). When voltage or momentary interruption occurs, the reactor has an unwanted trip by insertion of CARs and SORs even though the process systems are still in operation. HANARO was experienced in a nuisance trip as often as the unexpected voltage sag and/or momentary interruption occurs. We installed the voltage sag compensator on the power supply for CARs and SORs so as to prevent an unwanted trip. We undertook voltage sag assessment of the AC coil contactor which is a component of the power supply unit for the SORs. The compensation time is determined to be less than 1 sec in consideration of the reactor safety. This paper is concerned with the impact of the momentary interruption on the reactor and the effect of the voltage sag compensator

  15. Installation of the sag compensator for HANARO

    International Nuclear Information System (INIS)

    Electric power is essential for all industrial plants and also for nuclear facilities. HANARO is a research reactor which produces a 30MW thermal power. HANARO is designed to be tripped automatically when interruptions or some extent of sags occur. HANARO has the reactor regulation system(RRs) and reactor protection system(RPS). HANARO is designed so as to be tripped automatically by insertion of control absorber rods(CAR) and shut off rods(SOR). When voltage sag or momentary interruption occurs, the reactor has an unwanted trip by insertion of CARs and SORs even though the process systems are still in operation. HANARO was experienced in a nuisance trip as often as the unexpected voltage sag and/or momentary interruption occurs. We installed the voltage sag compensator voltage sag assessment of the AC coil contactor which is a component of the power supply unit for the SORs. The compensation time is determined to be less than 1 sec in consideration of the reactor safety. This paper is concerned with the impact of the momentary interruption on the reactor and the effect of the voltage sag compensator

  16. Direct Lorentz force compensation flowmeter for electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Vasilyan, S., E-mail: suren.vasilyan@tu-ilmenau.de; Froehlich, Th. [Institute of Process Measurement and Sensor Technology, Ilmenau University of Technology, 98684 Ilmenau (Germany)

    2014-12-01

    A simplified method of contactless Lorentz force (LF) measurements for flow meters on electrolytes is described and realized. Modification and comparative representation are discussed against recently well-developed methods. Based on the catapult effect, that current carrying conductor experiences a repulsive force in a magnetic field, we demonstrate force measurement method of LF velocimetry applications by commonly known “electromagnetic force” compensation principle. Measurement approach through zero point stability is considered to minimize mechanical influences and avoid gravimetric uncertainties. Here, the current carrying wires are static fixed in the vicinity of magnet system at zero point stable position, while occurring deflection of magnets by electrolyte flow is compensated by external applied current within wires. Measurements performed by developed servo-system which drives control loop by means of optical position sensor for simplified (i) single wire and (ii) coil-like extended compensation schemes. Guided by experiments on electrolyte flow, we demonstrate the applicability of adopted principle for conductivities ranging from 2 to 20 S/m. Further improvements are discussed in agreement with the parameters of demonstration setup, straightforward theory, and experimental results. We argue that this method is potentially suitable for: (a) applications with higher conductivity like molten metal (order of 10{sup 6 }S/m) assuming spatial configuration of setup and (b) for lower range of conductivity (below 1 S/m) while this is strongly subject to stiffness of system and noise mainly mechanical and thermal radiations.

  17. Direct Lorentz force compensation flowmeter for electrolytes

    Science.gov (United States)

    Vasilyan, S.; Froehlich, Th.

    2014-12-01

    A simplified method of contactless Lorentz force (LF) measurements for flow meters on electrolytes is described and realized. Modification and comparative representation are discussed against recently well-developed methods. Based on the catapult effect, that current carrying conductor experiences a repulsive force in a magnetic field, we demonstrate force measurement method of LF velocimetry applications by commonly known "electromagnetic force" compensation principle. Measurement approach through zero point stability is considered to minimize mechanical influences and avoid gravimetric uncertainties. Here, the current carrying wires are static fixed in the vicinity of magnet system at zero point stable position, while occurring deflection of magnets by electrolyte flow is compensated by external applied current within wires. Measurements performed by developed servo-system which drives control loop by means of optical position sensor for simplified (i) single wire and (ii) coil-like extended compensation schemes. Guided by experiments on electrolyte flow, we demonstrate the applicability of adopted principle for conductivities ranging from 2 to 20 S/m. Further improvements are discussed in agreement with the parameters of demonstration setup, straightforward theory, and experimental results. We argue that this method is potentially suitable for: (a) applications with higher conductivity like molten metal (order of 106 S/m) assuming spatial configuration of setup and (b) for lower range of conductivity (below 1 S/m) while this is strongly subject to stiffness of system and noise mainly mechanical and thermal radiations.

  18. Direct Lorentz force compensation flowmeter for electrolytes

    International Nuclear Information System (INIS)

    A simplified method of contactless Lorentz force (LF) measurements for flow meters on electrolytes is described and realized. Modification and comparative representation are discussed against recently well-developed methods. Based on the catapult effect, that current carrying conductor experiences a repulsive force in a magnetic field, we demonstrate force measurement method of LF velocimetry applications by commonly known “electromagnetic force” compensation principle. Measurement approach through zero point stability is considered to minimize mechanical influences and avoid gravimetric uncertainties. Here, the current carrying wires are static fixed in the vicinity of magnet system at zero point stable position, while occurring deflection of magnets by electrolyte flow is compensated by external applied current within wires. Measurements performed by developed servo-system which drives control loop by means of optical position sensor for simplified (i) single wire and (ii) coil-like extended compensation schemes. Guided by experiments on electrolyte flow, we demonstrate the applicability of adopted principle for conductivities ranging from 2 to 20 S/m. Further improvements are discussed in agreement with the parameters of demonstration setup, straightforward theory, and experimental results. We argue that this method is potentially suitable for: (a) applications with higher conductivity like molten metal (order of 106 S/m) assuming spatial configuration of setup and (b) for lower range of conductivity (below 1 S/m) while this is strongly subject to stiffness of system and noise mainly mechanical and thermal radiations

  19. Installation of the sag compensator for HANARO

    International Nuclear Information System (INIS)

    Electric power is essential for all industrial plants and also for nuclear facilities. HANARO is a research reactor which produces a 30 MW thermal power. HANARO is designed to be tripped automatically when interruptions or some extent of sags occur. HANARO has the reactor regulation system(RRS) and reactor protection system(RPS). HANARO is designed so as to be tripped automatically by insertion of control absorber rods(CAR) and shut-off rods(SOR). When voltage sag or momentary interruption occurs, the reactor has an unwanted trip by insertion of CARs and SORs even though the process systems are still in operation. HANARO was experienced in a nuisance trip as often as the unexpected voltage sag and/or momentary interruption occurs. We installed the voltage sag compensator on the power supply for CARs and SORs so as to prevent an unwanted trip. We undertook voltage sag assessment of the AC coil contactor which is a component of the power supply unit for the SORs. The compensation time is determined to be less than 1 sec in consideration of the reactor safety. This paper is concerned with the impact of the momentary interruption on the reactor and the effect of the voltage sag compensator. (author)

  20. Doppler Shift Compensation Schemes in VANETs

    Directory of Open Access Journals (Sweden)

    F. Nyongesa

    2015-01-01

    Full Text Available Over the last decade vehicle-to-vehicle (V2V communication has received a lot of attention as it is a crucial issue in intravehicle communication as well as in Intelligent Transportation System (ITS. In ITS the focus is placed on integration of communication between mobile and fixed infrastructure to execute road safety as well as nonsafety information dissemination. The safety application such as emergence alerts lays emphasis on low-latency packet delivery rate (PDR, whereas multimedia and infotainment call for high data rates at low bit error rate (BER. The nonsafety information includes multimedia streaming for traffic information and infotainment applications such as playing audio content, utilizing navigation for driving, and accessing Internet. A lot of vehicular ad hoc network (VANET research has focused on specific areas including channel multiplexing, antenna diversity, and Doppler shift compensation schemes in an attempt to optimize BER performance. Despite this effort few surveys have been conducted to highlight the state-of-the-art collection on Doppler shift compensation schemes. Driven by this cause we survey some of the recent research activities in Doppler shift compensation schemes and highlight challenges and solutions as a stock-taking exercise. Moreover, we present open issues to be further investigated in order to address the challenges of Doppler shift in VANETs.

  1. Finite Element Simulation for Springback Prediction Compensation

    Directory of Open Access Journals (Sweden)

    Agus Dwi Anggono

    2011-01-01

    Full Text Available An accurate modelling of the sheet metal deformations including the springback prediction is one of the key factors in the efficient utilisation of  Finite Element Method (FEM process simulation in industrial application. Assuming that springback can be predicted accurately, there still remains the problem of how to use such results to appear at a suitable die design to produce a target part shape. It  is  this  second  step  of  springback compensation that is addressed in the current work. This paper presents an  evaluation of a standard benchmark model defined as Benchmark II of Numisheet 2008, S-channel model with various drawbeads and blank holder force (BHF. The tool geometry modified based on springback calculation for a  part to compensate springback. The result shows that the combination of the smooth bead with BHF of 650 kN resulted in the minimum springback and the tool compensation was successfully to accommodate the springback errors.

  2. Method and apparatus for determining minority carrier diffusion length in semiconductors

    International Nuclear Information System (INIS)

    Method and apparatus are provided for determining the diffusion length of minority carriers in semiconductor material, particularly amorphous silicon, which has a significantly small minority carrier diffusion length using the constant magnitude surface-photovoltage (SPV) method. Steady or modulated illumination at several wavelengths provides the light excitation on the surface of the material to generate the SPV. A manually controlled or automatic servo system maintains a constant predetermined value of the SPB for each wavelength. A probe electrode immersed in an electrolyte solution containing redox couples (preferably quinhydrone) having an oxidation-reduction potential (E) in the order of +0.6 to -1.65 volts couples the SPV to a measurement system. The redox couple solution functions to create a liquid Schottky barrier at the surface of the material. The Schottky barrier is contacted by merely placing the probe in the solution. The redox solution is placed over and in contact with the material to be tested and light is passed through the solution to generate the SPV. To compensate for colored redox solutions a portion of the redox solution not over the material is also illuminated for determining the color compensated light intensity. Steady red light is also used as an optical bias to reduce deleterious space-charge effects that occur in amorphous silicon

  3. Deferred Executive Compensation Policies in Chinese State-owned Enterprises

    Institute of Scientific and Technical Information of China (English)

    Min Ju

    2007-01-01

    Since the commencement of industrial reform in China, most Chinese state-owned enterprises have adopted a deferred executive compensation policy to provide incentives for their management teams. However, the effectiveness of such a policy needs to be evaluated In this paper, we specify a model of deferred executive compensation policy, in which the compensation for executives is contingent on firms 'future revenue. The model suggests that under deferred executive compensation policies, managers exhibit an increasing level of effort in every period. Furthermore, the deferred compensation policy encourages managers to make long-term investments, which might generate revenue even after the termination of managerial contracts.

  4. A Novel Approach for Simulation of Transmission Line Compensation

    Directory of Open Access Journals (Sweden)

    Parag Nijhawan

    2010-10-01

    Full Text Available This paper presents an efficient method based on bus power injection for transmission line compensation. In this method, the load flow solution is first obtained using specified generations and loads. The terminal buses connecting the line to be compensated and the compensation level are identified. The differences of the line flows before and after compensation are injected in or out of the two terminal buses. The proposed method has been successfully used tosimulate compensation of transmission line by a series capacitor and then by SSSC.

  5. Fertility Compensation of Cornerstone Male Sterility of Wheat by Rye

    OpenAIRE

    Hossain, M. A.; Driscoll, C. J.

    1983-01-01

    The genome of rye is known to compensate for the lost male-fertility gene(s) of wheat chromosome arm 4Aα in the Cornerstone male-sterility mutant. A search for the rye chromosome(s) involved in this compensation showed that chromosomes 2R and 4R are responsible. Only the short arms of these two chromosomes are the operative ones. Chromosome arm 4RS compensates in an erratic way, whereas 2RS compensates in a full and consistent way. The entire chromosome 2R compensates less well than the 2RS ...

  6. Fixed order dynamic compensation for multivariable linear systems

    Science.gov (United States)

    Kramer, F. S.; Calise, A. J.

    1986-01-01

    This paper considers the design of fixed order dynamic compensators for multivariable time invariant linear systems, minimizing a linear quadratic performance cost functional. Attention is given to robustness issues in terms of multivariable frequency domain specifications. An output feedback formulation is adopted by suitably augmenting the system description to include the compensator states. Either a controller or observer canonical form is imposed on the compensator description to reduce the number of free parameters to its minimal number. The internal structure of the compensator is prespecified by assigning a set of ascending feedback invariant indices, thus forming a Brunovsky structure for the nominal compensator.

  7. 三相软开关PWM变流器电流极性检测与电流补偿方法%Current Polarity Detection and Current Compensation Strategy for PAC Based Three-Phase ZVS PWM Converter

    Institute of Scientific and Technical Information of China (English)

    屈克庆; 陈国呈; 孙承波

    2005-01-01

    A novel software implementation for current polarity detection and current compensation is presented. For a three-phase zero-voltage soft-switching (ZVS) PWM converter based on phase and amplitude control (PAC), when saw-tooth carriers with alternate positive and negative slopes are adopted, the positive or negative slopes are chosen according to the phase current polarity. Since polarity reversal causes current distortion, current at the instant of reversal should be compensated for. Based on the characteristic of unity power factor converter in rectification and regeneration modes, a software implementation for current polarity detection is proposed.Distortion of current zero-crossing caused by using saw-tooth carriers with alternate positive and negative slopes is analyzed, and the relevant compensation method is proposed. Experimental study with a 1.5 kW device shows that phase current has a small harmonic content and power factor is high both in rectification and regeneration modes.

  8. Dephasing of free carriers and excitons in bulk CdTe

    Energy Technology Data Exchange (ETDEWEB)

    Sprinzl, D.; Kunc, J.; Ostatnicky, T.; Horodysky, P.; Grill, R.; Franc, J.; Maly, P.; Nemec, P. [Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Prague 2 (Czech Republic)

    2007-05-15

    In this paper we report on the measurements of the dephasing of free carriers and excitons using a self-diffraction technique in thin platelets of CdTe with different concentration of preparation-induced dislocations. We show that in a high-quality sample at low temperature the characteristic dephasing time constant is 1 ps and 2 ps for free carriers and excitons, respectively. The increased concentration of preparation-induced dislocations leads to much stronger acceleration of the dephasing for free carriers than for excitons. We also discuss the intensity and temperature dependence of the dephasing. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. Differential Analysis of the Nasal Microbiome of Pig Carriers or Non-Carriers of Staphylococcus aureus.

    Science.gov (United States)

    Espinosa-Gongora, Carmen; Larsen, Niels; Schønning, Kristian; Fredholm, Merete; Guardabassi, Luca

    2016-01-01

    Staphylococcus aureus is presently regarded as an emerging zoonotic agent due to the spread of specific methicillin-resistant S. aureus (MRSA) clones in pig farms. Studying the microbiota can be useful for the identification of bacteria that antagonize such opportunistic veterinary and zoonotic pathogen in animal carriers. The aim of this study was to determine whether the nasal microbiome of pig S. aureus carriers differs from that of non-carriers. The V3-V5 region of the 16S rRNA gene was sequenced from nasal swabs of 44 S. aureus carriers and 56 non-carriers using the 454 GS FLX titanium system. Carriers and non-carriers were selected on the basis of quantitative longitudinal data on S. aureus carriage in 600 pigs sampled at 20 Danish herds included in two previous studies in Denmark. Raw sequences were analysed with the BION meta package and the resulting abundance matrix was analysed using the DESeq2 package in R to identify operational taxonomic units (OTUs) with differential abundance between S. aureus carriers and non-carriers. Twenty OTUs were significantly associated to non-carriers, including species with known probiotic potential and antimicrobial effect such as lactic acid-producing isolates described among Leuconostoc spp. and some members of the Lachnospiraceae family, which is known for butyrate production. Further 5 OTUs were significantly associated to carriage, including known pathogenic bacteria such as Pasteurella multocida and Klebsiella spp. Our results show that the nasal microbiome of pigs that are not colonized with S. aureus harbours several species/taxa that are significantly less abundant in pig carriers, suggesting that the nasal microbiota may play a role in the individual predisposition to S. aureus nasal carriage in pigs. Further research is warranted to isolate these bacteria and assess their possible antagonistic effect on S. aureus for the pursuit of new strategies to control MRSA in pig farming. PMID:27509169

  10. Differential Analysis of the Nasal Microbiome of Pig Carriers or Non-Carriers of Staphylococcus aureus

    Science.gov (United States)

    Espinosa-Gongora, Carmen; Larsen, Niels; Schønning, Kristian; Fredholm, Merete; Guardabassi, Luca

    2016-01-01

    Staphylococcus aureus is presently regarded as an emerging zoonotic agent due to the spread of specific methicillin-resistant S. aureus (MRSA) clones in pig farms. Studying the microbiota can be useful for the identification of bacteria that antagonize such opportunistic veterinary and zoonotic pathogen in animal carriers. The aim of this study was to determine whether the nasal microbiome of pig S. aureus carriers differs from that of non-carriers. The V3-V5 region of the 16S rRNA gene was sequenced from nasal swabs of 44 S. aureus carriers and 56 non-carriers using the 454 GS FLX titanium system. Carriers and non-carriers were selected on the basis of quantitative longitudinal data on S. aureus carriage in 600 pigs sampled at 20 Danish herds included in two previous studies in Denmark. Raw sequences were analysed with the BION meta package and the resulting abundance matrix was analysed using the DESeq2 package in R to identify operational taxonomic units (OTUs) with differential abundance between S. aureus carriers and non-carriers. Twenty OTUs were significantly associated to non-carriers, including species with known probiotic potential and antimicrobial effect such as lactic acid-producing isolates described among Leuconostoc spp. and some members of the Lachnospiraceae family, which is known for butyrate production. Further 5 OTUs were significantly associated to carriage, including known pathogenic bacteria such as Pasteurella multocida and Klebsiella spp. Our results show that the nasal microbiome of pigs that are not colonized with S. aureus harbours several species/taxa that are significantly less abundant in pig carriers, suggesting that the nasal microbiota may play a role in the individual predisposition to S. aureus nasal carriage in pigs. Further research is warranted to isolate these bacteria and assess their possible antagonistic effect on S. aureus for the pursuit of new strategies to control MRSA in pig farming. PMID:27509169

  11. Compensators for IMRT - an investigation in quality assurance

    International Nuclear Information System (INIS)

    Intensity modulated radiotherapy (IMRT) allows dose distributions which adequately consider organs at risk (OAR) and dose homogeneity to the target volume. This is practically reached by conforming the beam profiles to the shape of the planning target volume (PTV), by shaping the fluence with multileaf collimators (MLC) or compensators. Though compensator production is time consuming and seems less convenient than the use of MLC, compensators offer much easier quality assurance. In this study the effects of certain simplifications of compensator production were studied. Compensators were produced and ionization chamber measurements in a water phantom and film measurements in a solid phantom were performed to verify the compensators. The results of the measurements were compared to the fluence distributions given by the planning system. The measurements were meant to show how realistic the investigated simplifications were, and to reveal a suitable and reliable testing method for compensators. Monte-Carlo calculations employing the EGS 4 Code were further performed to support the measurements. (orig.)

  12. An Environment for Flexible Advanced Compensations of Web Service Transactions

    DEFF Research Database (Denmark)

    Schaefer, Michael; Dolog, Peter; Nejdl, Wolfgang

    2008-01-01

    Business to business integration has recently been performed by employing Web service environments. Moreover, such environments are being provided by major players on the technology markets. Those environments are based on open specifications for transaction coordination. When a failure in such an...... environment occurs, a compensation can be initiated to recover from the failure. However, current environments have only limited capabilities for compensations, and are usually based on backward recovery. In this article, we introduce an environment to deal with advanced compensations based on forward...... adapter components, which allow us to separate the compensation logic from the coordination logic. In this way, we can easily plug in or plug out different compensation strategies based on a specification language defined on top of basic compensation activities and complex compensation types. Experiments...

  13. Improvement of carrier injection symmetry and quantum efficiency in InGaN light-emitting diodes with Mg delta-doped barriers

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, F.; Can, N.; Hafiz, S.; Monavarian, M.; Das, S.; Avrutin, V.; Özgür, Ü., E-mail: uozgur@vcu.edu; Morkoç, H. [Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, Virginia 23284 (United States)

    2015-05-04

    The effect of δ-doping of In{sub 0.06}Ga{sub 0.94}N barriers with Mg on the quantum efficiency of blue light-emitting-diodes (LEDs) with active regions composed of 6 (hex) 3-nm In{sub 0.15}Ga{sub 0.85}N is investigated. Compared to the reference sample, δ-doping of the first barrier on the n-side of the LED structure improves the peak external quantum efficiency (EQE) by 20%, owing to the increased hole concentration in the wells adjacent to the n-side, as confirmed by numerical simulations of carrier distributions across the active region. Doping the second barrier, in addition to the first one, did not further enhance the EQE, which likely indicates compensation of improved hole injection by degradation of the active region quality due to Mg doping. Both LEDs with Mg δ-doped barriers effectively suppress the drop of efficiency at high injection when compared to the reference sample, and the onset of EQE peak roll-off shifts from ∼80 A/cm{sup 2} in the reference LED to ∼120 A/cm{sup 2} in the LEDs with Mg δ-doped barriers.

  14. Compensation for oil pollution damage caused by oil spills from ships and the International Oil Pollution Compensation Fund

    International Nuclear Information System (INIS)

    Liability and compensation for pollution damage caused by oil spills from laden tankers is governed by two international conventions: the 1969 Civil Liability Convention and the 1971 Fund Convention. The Civil Liability Convention established a system of strict liability for tanker owners and introduced compulsory liability insurance. The Fund Convention created a system of supplementary compensation administered by an intergovernmental organization, the International Oil Pollution Compensation Fund (IOPC Fund), which at present has 56 member states (August 1993). The IOPC Fund pays compensation to victims of oil pollution in member states when the compensation from the ship owner and his insurer is insufficient. (author)

  15. 49 CFR 1139.22 - Revenue data for study carriers.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Revenue data for study carriers. 1139.22 Section... BOARD, DEPARTMENT OF TRANSPORTATION RULES OF PRACTICE PROCEDURES IN MOTOR CARRIER REVENUE PROCEEDINGS Intercity Bus Industry § 1139.22 Revenue data for study carriers. The study carriers, as identified...

  16. 76 FR 32390 - Motor Carrier Safety Advisory Committee Public Meeting

    Science.gov (United States)

    2011-06-06

    ... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION: Notice of Motor Carrier Safety Advisory... MCSAC will complete action on Task 11-01, regarding Patterns of Safety Violations by Motor...

  17. 75 FR 2923 - Motor Carrier Safety Advisory Committee Public Meeting

    Science.gov (United States)

    2010-01-19

    ... sessions announced on January 5, 2010 (75 FR 285), and elsewhere in today's Federal Register, and to... Federal Motor Carrier Safety Administration Motor Carrier Safety Advisory Committee Public Meeting AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION: Notice of Motor Carrier Safety...

  18. Transuranic separation using organophophorus extractants adsorbed onto superparamagnetic carriers

    International Nuclear Information System (INIS)

    Polymeric coated ferromagnetic carriers with an absorbed layer of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) diluted by tributyl phosphate (TBP) are being evaluated for application in the separation and the recovery of low concentrations of americium, plutonium, and uranium from nuclear waste solutions. Due to their chemical nature, these extractants selectively complex americium and plutonium contaminants onto the particles and the complexed particles can be recovered from the solution using a magnet. Physical and chemical characterization of the extractant-absorbed particles were performed by gamma and liquid scintillation counting, scanning electron microscopic (SEM) micrograph, and other physical measurements. Plutonium, americium, and uranium separations have been performed at various HNO3 and HCl concentrations. Parameters were studied to determine the limitations and capacity of the process. The status of the chemistry and application of the process to Department of Energy (DOE) remediation efforts for actinide decontamination are discussed

  19. Charge carrier transport in liquid crystals

    International Nuclear Information System (INIS)

    The materials exhibiting charge carrier mobility ranging from 10−3 to 0.1 cm2/Vs, i.e., between those of amorphous and crystalline materials, had been missing before the 1990s when the electronic conduction in liquid crystals was discovered. Since then, various liquid crystalline materials including discotic and calamitic liquid crystals have been studied in order to clarify their charge carrier transport properties in liquid crystalline mesophases. In this article, the historical background of the discovery of electronic conduction in liquid crystals, intrinsic and extrinsic conductions, unique properties of the charge carrier transport, the effect of molecular alignment on it, and the conduction mechanism in liquid crystalline mesophases are shortly described on the basis of the experimental and theoretical studies accumulated in these two decades, noting that the missing materials were liquid crystals. - Highlights: • Liquid crystals exhibit charge mobility ranging from 10–3 to 0.1 cm2/Vs. • Electronic (intrinsic) and ionic (extrinsic) conductions in liquid crystals • Unique charge carrier transport properties in liquid crystals • Effect of molecular alignment in mesophases on charge carrier transport • Conduction mechanism in smectic liquid crystals

  20. Extracting hot carriers from photoexcited semiconductor nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Xiaoyang

    2014-12-10

    This research program addresses a fundamental question related to the use of nanomaterials in solar energy -- namely, whether semiconductor nanocrystals (NCs) can help surpass the efficiency limits, the so-called “Shockley-Queisser” limit, in conventional solar cells. In these cells, absorption of photons with energies above the semiconductor bandgap generates “hot” charge carriers that quickly “cool” to the band edges before they can be utilized to do work; this sets the solar cell efficiency at a limit of ~31%. If instead, all of the energy of the hot carriers could be captured, solar-to-electric power conversion efficiencies could be increased, theoretically, to as high as 66%. A potential route to capture this energy is to utilize semiconductor nanocrystals. In these materials, the quasi-continuous conduction and valence bands of the bulk semiconductor become discretized due to confinement of the charge carriers. Consequently, the energy spacing between the electronic levels can be much larger than the highest phonon frequency of the lattice, creating a “phonon bottleneck” wherein hot-carrier relaxation is possible via slower multiphonon emission. For example, hot-electron lifetimes as long as ~1 ns have been observed in NCs grown by molecular beam epitaxy. In colloidal NCs, long lifetimes have been demonstrated through careful design of the nanocrystal interfaces. Due to their ability to slow electronic relaxation, semiconductor NCs can in principle enable extraction of hot carriers before they cool to the band edges, leading to more efficient solar cells.