391   MMIC compatible photonic A/D converter MMIC compatible photonic A/D converter    1999 The performance of RF surveillance systems can be improved by taking a direct conversion receiver approach. This report proposes an analogue-to-digital converter (ADC) for this application which uses Sigma-Delta lowpass and bandpass modulator structures implemented with an ultra low timing jitter (ULTJ) over-sampling clock and novel opto-electronic components. 查看全文

392   Preliminary study on LGM climate simulation and the diagnosis for East Asia Preliminary study on LGM climate simulation and the diagnosis for East Asia Ge Yu, Xing Chen, Jian Liu;Sumin Wang    2001 LGM climate study is a hot topic in international fields on global changes. Climate simulation in this study applies both common designs of 21 kaBP boundary conditions from the Paleoclimate Modeling Intercomparison Project (PMIP), including insolation, glaciation, sea surface temperature and atmospheric CO2 concentration, and land surface conditions from Eurasia continent by compilation of geological evidence. The simulation outputs are in agreement with climate ... 查看全文

393   PM noise measurements of an actively modelocked external cavity semiconductor ring laser at 10 GHz PM noise measurements of an actively modelocked external cavity semiconductor ring laser at 10 GHz    2001 A novel approach to residual jitter measurement examines the intensity crosscorrelation generated by two optical pulses with various relative delays. A relative delay of 25 pulses produces a residual jitter value of 26 fsec RMS for a 10 GHz actively modelocked ring laser. The phase noise measurement carried out to the Nyquist frequency (5 GHz) offset gives 47 fsec RMS pulse-to-pulse timing jitter. The field correlation measurement obtains a 10 asec RMS pulse-to-pulse optical carder jitter. 查看全文

394   Development of a 10 Gbit/s optical soliton source Development of a 10 Gbit/s optical soliton source    2000 In this work we demonstrated the feasibility of a 10 Gbit/s optical soliton source based on direct modulation of a semiconductor laser. We also show that it is possible to reduce substantially the frequency chirp, induced by the direct modulation process, with a narrow optical filter. A peak power greater than 100 mW is achieved with an optical signal-to-noise ratio (OSNR) better than 39 dB. We measured the output timing jitter of the source and we show that its main contribution is due to the l... 查看全文

395   Adda or the Oldest Extant Dispute Between Jains and Heretics (Sūyagada 2, 6) Part two Adda or the Oldest Extant Dispute Between Jains and Heretics (Sūyagada 2, 6) Part two W. B. Bollee    1999 查看全文

396   Generation of 10 GHz, 1.9 ps optical pulse train using semiconductor optical amplifier and silica-based highly nonlinear fiber Generation of 10 GHz, 1.9 ps optical pulse train using semiconductor optical amplifier and silica-based highly nonlinear fiber    2010 We propose a simple approach to generate a high quality 10 GHz 1.9 ps optical pulse train using a semiconductor optical amplifier and silica-based highly nonlinear fiber. An optical pulse generator based on our proposed scheme is easy to set up with commercially available optical components. A 10 GHz, 1.9 ps optical pulse train is obtained with timing jitter as low as 60 fs over the frequency range 10 Hz-1 MHz. With a wavelength tunable CW laser, a wide wavelength tunable span can be achieved ov... 查看全文

397   Iterative threshold segmentation for PET target volume delineation Iterative threshold segmentation for PET target volume delineation Laura Drever;Wilson Roa;Alexander McEwan;Don Robinson    0 The purpose of this work is to create a rigorous method of segmenting PET images using an automated iterative technique. To this end a phantom study employing spherical targets was used to determine local (slice specific) threshold levels which produce correct cross-sections based on the contrast between target and background. Numerous target to background activity concentration ratios were investigated but found to have minimal effect in comparison to the influence of target size. Functions wer... 查看全文

398   Trienamine Catalysis with 2,4-Dienones: Development and Application in Asymmetric Diels–Alder Reactions† Trienamine Catalysis with 2,4-Dienones: Development and Application in Asymmetric Diels–Alder Reactions†    2012 查看全文

399   Learning from the past to prepare for the future: Modeling the impact of hypothetical interventions during the great influenza pandemic of 1918 Learning from the past to prepare for the future: Modeling the impact of hypothetical interventions during the great influenza pandemic of 1918 Mark Glickman, Gerardo Chowell, N. W. Hengartner, Catherine Ammon;Mac Hyman    2008 查看全文

400   Effect of Nature and Location of Defects on Bandgap Narrowing in Black TiO2 Nanoparticles Effect of Nature and Location of Defects on Bandgap Narrowing in Black TiO2 Nanoparticles Alberto Naldoni*†, Mattia Allieta§, Saveria Santangelo‡, Marcello Marelli†, Filippo Fabbri#, Serena    2012 The increasing need for new materials capable of solar fuel generation is central in the development of a green energy economy. In this contribution, we demonstrate that black TiO2 nanoparticles obtained through a one-step reduction/crystallization process exhibit a bandgap of only 1.85 eV, which matches well with visible light absorption. The electronic structure of black TiO2 nanoparticles is determined by the unique crystalline and defective core/disordered shell morphology. We introduce new ... 查看全文

401   Singular value decomposition based computationally efficient algorithm for rapid dynamic near-infrared diffuse optical tomography Singular value decomposition based computationally efficient algorithm for rapid dynamic near-infrared diffuse optical tomography Saurabh Gupta;Ram M. Vasu;Phaneendra K. Yalavarthy;Debasish Roy;Daqing Piao    0 Purpose: A computationally efficient algorithm (linear iterative type) based on singular value decomposition (SVD) of the Jacobian has been developed that can be used in rapid dynamic near-infrared (NIR) diffuse optical tomography. 查看全文

402   40 Gb/s all-optical clock recovery using high finesse Fabry-Perot filter 40 Gb/s all-optical clock recovery using high finesse Fabry-Perot filter    2010 An all-optical clock recovery scheme based on a high fitness Fabry-Perot(F-P) filter is proposed and experimentally demonstrated. In order to make the scheme insensitive to the signal wavelength, wavelength conversion based on the cross phase modulation(XPM) in the fiber is done, so that the wavelength of the converted signal is always set exactly to the peak wavelength of the F-P filter. An F-P filter with the finesse up to 1012 is used to extract the clock, and the low frequency noise is conse... 查看全文

403   The Combination of Relay and Cooperative Catalysis with a Gold/Palladium/Brønsted Acid Ternary System for the Cascade Hydroamination/Allylic Alkylation Reaction The Combination of Relay and Cooperative Catalysis with a Gold/Palladium/Brønsted Acid Ternary System for the Cascade Hydroamination/Allylic Alkylation Reaction Beacute;la Touml;rouml;k, Katalin Balaacute;zsik, Gyouml;rgy Szouml;llouml;si, Kaacute;roly Felfouml    2012 The combination of relay and cooperative catalysis with a gold/palladium/Brønsted acid ternary system renders a cascade hydroamination/allylic alkylation reaction to provide an unprecedented entry to pyrrolidine derivatives in high yields. 查看全文

404   Special Issue: 2008 Copper Mountain Conference Special Issue: 2008 Copper Mountain Conference Ray Tuminaro    0 The biennial Copper Mountain Conference on Iterative Methods was held April 6–11, 2008. This most recent meeting included both theoretical and applied presentations spanning a broad range of iterative/linear algebra topics such as saddle-point systems, eigensolvers, nonlinear solvers, inverse problems, and block solution methods. The diverse impact of iterative method research can be gauged by the broad range of application areas represented at the meeting. Some of these include computational fl 查看全文

405   Experimental measurement and theoretical explanation of time jitter in pulse modulated semiconductor lasers Experimental measurement and theoretical explanation of time jitter in pulse modulated semiconductor lasers    1988 The authors report a systematic investigation of the statistical properties of the turn-on-time jitter that arises when semiconductor lasers are suddenly switched from below to above threshold by means of a current pulse. Previous experimental studies have shown the presence of nonzero time jitter in distributed-feedback (DFB) lasers. The present measurements confirm the presence of time jitter in Fabry-Perot lasers, even though its magnitude is much less than in DFB lasers. However, contrary to... 查看全文

406   The Influence of Antisite Defects on the Half-Metallic Properties in Disordered LaSrVMoO6 The Influence of Antisite Defects on the Half-Metallic Properties in Disordered LaSrVMoO6 Jing Wang†, Xiaobo Sun‡, and Zhijian Wu*†    2011 Electronic and magnetic properties of disordered LaSrVMoO6 are investigated by the use of density functional theory. Our results indicate that the antisite defects reduce the magnetization. The Coulomb interaction (U) plays a vital role in producing the half-metallic properties, and the magnetic ground state is also sensitive to the choice of U. A compensated half-metal is obtained in completely disordered cubic LaSrVMoO6, which is the first evidence for the compensated half-metal in LaSrVMoO6. ... 查看全文

407   Advances in Lipid Treatment Postgraduate Course at the New York University School of Medicine June 19, 2004 Advances in Lipid Treatment Postgraduate Course at the New York University School of Medicine June 19, 2004    2006 查看全文

408   Inhalation toxicity of furfural vapours: An assessment of biochemical response in rat lungs Inhalation toxicity of furfural vapours: An assessment of biochemical response in rat lungs    2006 The pulmonary biochemical response, particularly the effects on mixed-function oxidases, was investigated in rats exposed to 40 ppm furfural for 1 h daily, 5 days per week, for periods of 7, 15 and 30 days. This concentration is ca. 22% of the acute LC50 dose. Exposure to furfural increased the activities of acid and alkaline phosphatases and glutamic-pyruvic transaminase, inhibited the activities of arginase and succinic dehydrogenases and elevated the concentration of lactic acid in the lungs.... 查看全文

409   Intensive Family Preservation Services: The Perceptions of Client Families Intensive Family Preservation Services: The Perceptions of Client Families Frank G. Kauffman    2007 This qualitative study seeks to understand the correlation between intensive family preservation services and family functioning in those families who have participated in services. The focus is on the perceptions of client families with respect to the impact of services on family functioning including communication, family dynamics, and parenting skills. The discussion centers on the responses of client families to a narrowly constructed survey instrument designed to cap... 查看全文

410   Determinants of perceived role conflict among women in bangladesh Determinants of perceived role conflict among women in bangladesh Quazi Shamsuddin    1990 The purpose of the present study was to find important determinants of perceived role conflict (PRC) by building a regression model. The paper examined the joint linear influences of wife's age, her income, her time for household chores and outside job, her female role perception (FRP), husband's income, his time for household work and outside job, total number of children, child-density, age of youngest child, and age of oldest unmarried girl to the variance of PRC of women. It also examined re... 查看全文

411   Sex differences in behavioral and cognitive aspects of decision control Sex differences in behavioral and cognitive aspects of decision control Pamela Lind;Helen Connole    1985 Sex differences in three components of decision control were examined in a series of studies utilizing 4-, 9-, and 14-year-old subjects. These components were actual decision control behavior, the cognitive understanding of the masculine or feminine nature of decision control, and the self-perception of decision control skills. At the behavioral level, boys controlled more decision outcomes than girls, especially at the oldest age grouping. In the area of self-perception, girls were less likely ... 查看全文

412   A Mediterranean-Style. Diet and Metabolic Syndrome A Mediterranean-Style. Diet and Metabolic Syndrome    2008 A moderate increase in physical activity and a detailed and tailored Mediterranean-style. diet reduce the prevalence of metabolic syndrome and associated cardiovascular risks through reducing systemic vascular inflammation and endothelium dysfunction, particularly in those patients who do not lose weight. 查看全文

413   Old soils and land surfaces on the Galápagos islands Old soils and land surfaces on the Galápagos islands H. Franz    1980 Modern rock dating tells that the Galápagos Islands are geologically very young. No rocks have yet been discovered older than two million years. Nevertheless old landscapes with rounded forms exist side by side with more or very recent volcanoes and lava flows and a number of old marine terraces are distinguisable. Red soils have formed only in the old landscapes (high areas of the oldest islands and on the oldest coastal terraces). Their profile has been preserved only in remnants that h... 查看全文

414   40Gbit/s all-optical 3R regeneration based on F-P filter and SOA 40Gbit/s all-optical 3R regeneration based on F-P filter and SOA    2005 40Gbit/s all-optical 3R regeneration was demonstrated. The wavelength of the data signal was converted with an SOA by cross-gain modulation (XGM). The clock recovery was based on Fabry-Pe´rot (F-P) filter of high finesse (F=1000). The actual bit rate of the data signal was 40.04796Gbit/s, matching the free spectral range (FSR) of the F-P filter. Two SOAs were used in series as the decision gate to make full use of the nonlinearity. Taking advantage of the chirp, one narrowband OBF was used... 查看全文

415   A qualitative study on the acceptability and preference of three types of long-lasting insecticide-treated bed nets in Solomon Islands: implications for malaria elimination A qualitative study on the acceptability and preference of three types of long-lasting insecticide-treated bed nets in Solomon Islands: implications for malaria elimination Jo-An Atkinson, Albino Bobogare, Lisa Fitzgerald, Leonard Boaz, Bridget Appleyard, Hilson Toaliu;;re    2009 Background  In March 2008, the Solomon Islands and Vanuatu governments raised the goal of their National Malaria Programmes from control to elimination. Vector control measures, such as indoor residual spraying (IRS) and long-lasting insecticidal bed nets (LLINs) are key integral components of this programme. Compliance with these interventions is dependent on their acceptability and on the socio-cultural context of the local populatio... 查看全文

416   Observation of quantum-limited timing jitter in an active, harmonically mode-locked fiber laser Observation of quantum-limited timing jitter in an active, harmonically mode-locked fiber laser    2002 We report on the observation of quantum-limited timing jitter in a harmonically mode-locked soliton fiber laser with an ultralow-noise local oscillator. The effects of amplitude and phase modulation on the spectrum are described and compared with theory. © 2002 Optical Society of America. 查看全文

417   Hybrid mode-locking of a monolithic semiconductor laser on semi-insulating InP substrate Hybrid mode-locking of a monolithic semiconductor laser on semi-insulating InP substrate    2001 Monolithic colliding pulse mode-locked (CPM) lasers operating at 1.5 μm and 36 GHz repetition frequency were fabricated on semi-insulating substrates. An RF electrical signal at a subharmonic frequency was injected into the saturable absorber at various injected RF power levels, and both the phase noise and timing jitter were characterised. Under fundamental hybrid mode-locking (FH-ML) case, the worst-case timing jitter was reduced from 4.8 ps to 0.69 ps with an injected RF power of +8 dBm. F... 查看全文

418   Effects of astragaloside IV on pathogenesis of metabolic syndrome in vitro† Effects of astragaloside IV on pathogenesis of metabolic syndrome in vitro†    2006 Aim: To investigate the diverse pharmacological actions of astragaloside IV from the perspective of metabolic syndrome, and to investigate the effect of the drug on the pathogenesis of metabolic syndrome. Methods: Adipogenesis was used as an indicator of the effect of astragaloside IV on preadipocyte differentiation, and was measured by using an oil red O assay. Glucose uptake was determined by measuring the transport of [2-3H]-deoxyglucose into the cells. The concentrations of peroxisome prolif... 查看全文

419   Action on pulse position and momentum using dispersion and phase modulation Action on pulse position and momentum using dispersion and phase modulation    2001 The timing jitter and frequency jitter of quantized optical pulses obey Heisenberg's uncertainty principle. We show how one jitter may be reduced at the expense of the other, using dispersion and phase modulation. © 2001 Optical Society of America. 查看全文

420   Convergence characteristics of proportional-type iterative learning control in the sense of Lebesgue-p norm Convergence characteristics of proportional-type iterative learning control in the sense of Lebesgue-p norm X. Ruan    0 This article studies convergence characteristics of first- and second-order P-type (proportional-type) iterative learning control laws for a class of partially known linear time-invariant systems with a direct feed-through term. In the study, the tracking error is measured in the sense of Lebesgue-p norm, based on which the concepts of the Qp factor and the convergence speed are specified. For the first-order updating law, the monotone convergence is achieved by means of the generalised Young in... 查看全文

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