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Journal articles on the topic 'Frequency references'

Author: Grafiati

Published: 4 June 2021

Last updated: 4 February 2022

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1

Jefferts, Steven R., Thomas P. Heavner, and Elizabeth A. Donley. "Cesium Primary Frequency References." Japanese Journal of Applied Physics 43, no. 5B (May 28, 2004): 2803–7. http://dx.doi.org/10.1143/jjap.43.2803.

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2

Hollberg, L., C. W. Oates, G. Wilpers, C. W. Hoyt, Z. W. Barber, S. A. Diddams, W. H. Oskay, and J. C. Bergquist. "Optical frequency/wavelength references." Journal of Physics B: Atomic, Molecular and Optical Physics 38, no. 9 (April 25, 2005): S469—S495. http://dx.doi.org/10.1088/0953-4075/38/9/003.

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3

Kitching, J., S. Knappe, L. Liew, J. Moreland, P. D. D. Schwindt, V. Shah, V. Gerginov, and L. Hollberg. "Microfabricated atomic frequency references." Metrologia 42, no. 3 (June 2005): S100—S104. http://dx.doi.org/10.1088/0026-1394/42/3/s11.

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4

Schuldt, Thilo, Klaus Döringshoff, Markus Oswald, Ulrich Johann, Achim Peters, and Claus Braxmaier. "Iodine frequency references for space." Journal of Physics: Conference Series 840 (May 2017): 012050. http://dx.doi.org/10.1088/1742-6596/840/1/012050.

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5

Kitching, J., S. Knappe, and L. Hollberg. "Miniature vapor-cell atomic-frequency references." Applied Physics Letters 81, no. 3 (July 15, 2002): 553–55. http://dx.doi.org/10.1063/1.1494115.

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6

Schuldt, Thilo, Klaus Döringshoff, Alexander Milke, Josep Sanjuan, Martin Gohlke, Evgeny V. Kovalchuk, Norman Gürlebeck, Achim Peters, and Claus Braxmaier. "High-Performance Optical Frequency References for Space." Journal of Physics: Conference Series 723 (June 2016): 012047. http://dx.doi.org/10.1088/1742-6596/723/1/012047.

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7

Filho, Rubens Dolce. "The frequency of dietary references in homeopathic consultations." Homeopathy 100, no. 3 (July 2011): 144–47. http://dx.doi.org/10.1016/j.homp.2011.04.002.

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8

Ishida, O., and H. Toba. "Lightwave synthesizer with lock-in-detected frequency references." Journal of Lightwave Technology 9, no. 10 (1991): 1344–52. http://dx.doi.org/10.1109/50.90933.

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9

Papoyan, A. V., and D. H. Sarkisyan. "Optical Frequency References Based on Alkali Metal Vapor Nanocells." Физические основы приборостроения 5, no. 1 (March 15, 2016): 42–49. http://dx.doi.org/10.25210/jfop-1601-042049.

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10

Sebbag, Yoel, Roy Zektzer, Yefim Barash, and Uriel Levy. "Toward Stand-Alone Alkali-Based Mid-Infrared Frequency References." ACS Photonics 7, no. 6 (May 19, 2020): 1508–14. http://dx.doi.org/10.1021/acsphotonics.0c00308.

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11

Miller, Barton P. "The frequency of dynamic pointer references in “C” programs." ACM SIGPLAN Notices 23, no. 6 (June 1988): 152–56. http://dx.doi.org/10.1145/44546.44562.

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12

Foreman, Seth M., Kevin W. Holman, Darren D. Hudson, David J. Jones, and Jun Ye. "Remote transfer of ultrastable frequency references via fiber networks." Review of Scientific Instruments 78, no. 2 (February 2007): 021101. http://dx.doi.org/10.1063/1.2437069.

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13

Savchenkov, Anatoliy A., Andrey B. Matsko, Vladimir S. Ilchenko, Nan Yu, and Lute Maleki. "Whispering-gallery-mode resonators as frequency references II Stabilization." Journal of the Optical Society of America B 24, no. 12 (November 14, 2007): 2988. http://dx.doi.org/10.1364/josab.24.002988.

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14

Foley, Tim, and Christopher J. Ryan. "The frequency of references to decision-making capacity in reports to the NSW Mental Health Review Tribunal did not change after legislative reforms that promoted them." Australasian Psychiatry 28, no. 2 (February 4, 2020): 171–74. http://dx.doi.org/10.1177/1039856220901475.

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Objective: To assess the impact of a 2015 reform to the Mental Health Act 2007 (NSW) ( MHA) that was interpreted as requiring a reference to decision-making capacity (DMC) in reports to the NSW Mental Health Review Tribunal (MHRT). Method: A sample of reports to the MHRT were audited for references to the MHA’s treatment criteria and DMC in periods before and after the reforms, and the frequency of references between the two periods was compared. Results: The frequency of references to DMC did not change significantly after the reforms. (However, references to the ‘least restriction’ criterion increased markedly between the two periods). Conclusion: Despite legislative reforms and a supporting education campaign promoting the importance of consideration of DMC, references to DMC did not increase after the reforms.

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15

Al-Khalidy, Hatmal Odeh. "Discourse Analysis of References in the Speech of Amir of Qatar Sheik Tamim Bin Hamad Al -Thani in the 72 Session of the United Nations General Assembly." International Journal of Linguistics 10, no. 6 (December 31, 2018): 291. http://dx.doi.org/10.5296/ijl.v10i6.14158.

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Discourse as a connected speech which extends beyond the borders of a single sentence. Therefore, this study analyse references in the speech of Amir of Qatar Sheik Tamim Bin Hamad Al -Thani in the 72 session of the United Nations General Assembly on 19- September 2017. The researcher will present personal, demonstratives and comparative references by analysing their frequency of occurrence as an analytical study. Basically, this study reveals that personal references are most frequently used by Sheik Tamim, followed by demonstrative references. The comparative references happen to be the least occurring type.

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16

Lenci, L., A. Lezama, and H. Failache. "Dark resonances in thin cells for miniaturized atomic-frequency references." Optics Letters 34, no. 4 (February 6, 2009): 425. http://dx.doi.org/10.1364/ol.34.000425.

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17

Matsko, Andrey B., Anatoliy A. Savchenkov, Nan Yu, and Lute Maleki. "Whispering-gallery-mode resonators as frequency references I Fundamental limitations." Journal of the Optical Society of America B 24, no. 6 (May 17, 2007): 1324. http://dx.doi.org/10.1364/josab.24.001324.

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18

Knappe, Svenja, Robert Wynands, John Kitching, Hugh G. Robinson, and Leo Hollberg. "Characterization of coherent population-trapping resonances as atomic frequency references." Journal of the Optical Society of America B 18, no. 11 (November 1, 2001): 1545. http://dx.doi.org/10.1364/josab.18.001545.

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19

Weis, Jan, Jonas Persson, Andreas Frick, Fredrik Åhs, Maarten Versluis, and Daniel Alamidi. "GABA quantification in human anterior cingulate cortex." PLOS ONE 16, no. 1 (January 15, 2021): e0240641. http://dx.doi.org/10.1371/journal.pone.0240641.

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γ-Aminobutyric acid (GABA) is a primary inhibitory neurotransmitter in the human brain. It has been shown that altered GABA concentration plays an important role in a variety of psychiatric and neurological disorders. The main purpose of this study was to propose a combination of PRESS and MEGA-PRESS acquisitions for absolute GABA quantification and to compare GABA estimations obtained using total choline (tCho), total creatine (tCr), and total N-acetyl aspartate (tNAA) as the internal concentration references with water referenced quantification. The second aim was to demonstrate the fitting approach of MEGA-PRESS spectra with QuasarX algorithm using a basis set of GABA, glutamate, glutamine, and NAA in vitro spectra. Thirteen volunteers were scanned with the MEGA-PRESS sequence at 3T. Interleaved water referencing was used for quantification, B0 drift correction and to update the carrier frequency of RF pulses in real time. Reference metabolite concentrations were acquired using a PRESS sequence with short TE (30 ms) and long TR (5000 ms). Absolute concentration were corrected for cerebrospinal fluid, gray and white matter water fractions and relaxation effects. Water referenced GABA estimations were significantly higher compared to the values obtained by metabolite references. We conclude that QuasarX algorithm together with the basis set of in vitro spectra improves reliability of GABA+ fitting. The proposed GABA quantification method with PRESS and MEGA-PRESS acquisitions enables the utilization of tCho, tCr, and tNAA as internal concentration references. The use of different concentration references have a good potential to improve the reliability of GABA estimation.

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20

Weng, Wenle, Aleksandra Kaszubowska-Anandarajah, Junqiu Liu, Prince M. Anandarajah, and Tobias J. Kippenberg. "Frequency division using a soliton-injected semiconductor gain-switched frequency comb." Science Advances 6, no. 39 (September 2020): eaba2807. http://dx.doi.org/10.1126/sciadv.aba2807.

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With optical spectral marks equally spaced by a frequency in the microwave or the radio frequency domain, optical frequency combs have been used not only to synthesize optical frequencies from microwave references but also to generate ultralow-noise microwaves via optical frequency division. Here, we combine two compact frequency combs, namely, a soliton microcomb and a semiconductor gain-switched comb, to demonstrate low-noise microwave generation based on a novel frequency division technique. Using a semiconductor laser that is driven by a sinusoidal current and injection-locked to microresonator solitons, our scheme transfers the spectral purity of a dissipative soliton oscillator into the subharmonic frequencies of the microcomb repetition rate. In addition, the gain-switched comb provides dense optical spectral emissions that divide the line spacing of the soliton microcomb. With the potential to be fully integrated, the merger of the two chipscale devices may profoundly facilitate the wide application of frequency comb technology.

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21

Savchenkov, A. A., A. B. Matsko, and L. Maleki. "On Frequency Combs in Monolithic Resonators." Nanophotonics 5, no. 2 (June 1, 2016): 363–91. http://dx.doi.org/10.1515/nanoph-2016-0031.

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AbstractOptical frequency combs have become indispensable in astronomical measurements, biological fingerprinting, optical metrology, and radio frequency photonic signal generation. Recently demonstrated microring resonator-based Kerr frequency combs point the way towards chip scale optical frequency comb generator retaining major properties of the lab scale devices. This technique is promising for integrated miniature radiofrequency and microwave sources, atomic clocks, optical references and femtosecond pulse generators. Here we present Kerr frequency comb development in a historical perspective emphasizing its similarities and differences with other physical phenomena. We elucidate fundamental principles and describe practical implementations of Kerr comb oscillators, highlighting associated solved and unsolved problems.

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22

Huang, Shu-Wei, Jinghui Yang, Mingbin Yu, Bart H. McGuyer, Dim-Lee Kwong, Tanya Zelevinsky, and Chee Wei Wong. "A broadband chip-scale optical frequency synthesizer at 2.7 × 10−16 relative uncertainty." Science Advances 2, no. 4 (April 2016): e1501489. http://dx.doi.org/10.1126/sciadv.1501489.

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Optical frequency combs—coherent light sources that connect optical frequencies with microwave oscillations—have become the enabling tool for precision spectroscopy, optical clockwork, and attosecond physics over the past decades. Current benchmark systems are self-referenced femtosecond mode-locked lasers, but Kerr nonlinear dynamics in high-Q solid-state microresonators has recently demonstrated promising features as alternative platforms. The advance not only fosters studies of chip-scale frequency metrology but also extends the realm of optical frequency combs. We report the full stabilization of chip-scale optical frequency combs. The microcomb’s two degrees of freedom, one of the comb lines and the native 18-GHz comb spacing, are simultaneously phase-locked to known optical and microwave references. Active comb spacing stabilization improves long-term stability by six orders of magnitude, reaching a record instrument-limited residual instability of 3.6mHz/τ. Comparing 46 nitride frequency comb lines with a fiber laser frequency comb, we demonstrate the unprecedented microcomb tooth-to-tooth relative frequency uncertainty down to 50 mHz and 2.7 × 10−16, heralding novel solid-state applications in precision spectroscopy, coherent communications, and astronomical spectrography.

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23

Szymaniec, K., R. J. Hendricks, K. Turza, B. Nagórny, P. Dunst, J. Nawrocki, P. Krehlik, Ł. Śliwczyński, and A. Czubla. "Operation of caesium fountain frequency standards with remote hydrogen maser references." Metrologia 55, no. 6 (October 19, 2018): 782–88. http://dx.doi.org/10.1088/1681-7575/aae40d.

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24

Kitching, J., H. G. Robinson, L. Hollberg, S. Knappe, and R. Wynands. "Optical-pumping noise in laser-pumped, all-optical microwave frequency references." Journal of the Optical Society of America B 18, no. 11 (November 1, 2001): 1676. http://dx.doi.org/10.1364/josab.18.001676.

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25

Wrenn, Robert L., and Patti Harada. "Literature in Death, Dying and Bereavement Viewed from the Basic Text." OMEGA - Journal of Death and Dying 39, no. 4 (December 1999): 287–95. http://dx.doi.org/10.2190/y5v3-tky0-prqq-xxdk.

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The basic text books in Death and Dying make numerous references to the literature. A sample of five such texts disclosed that each covers similar topics, but with noted exceptions, they use references that are unique to each text. The authors' areas of special interest are indicated in these texts by the frequency of references cited within those topics of special interest. An operational definition of what is a “classic” reference to the field is offered by tallying those reference cited by all text authors.

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26

Gerginov, Vladislav, Svenja Knappe, Vishal Shah, Peter D. D. Schwindt, Leo Hollberg, and John Kitching. "Long-term frequency instability of atomic frequency references based on coherent population trapping and microfabricated vapor cells." Journal of the Optical Society of America B 23, no. 4 (April 1, 2006): 593. http://dx.doi.org/10.1364/josab.23.000593.

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27

Jones, Roger W., and John F. McClelland. "Phase References and Cell Effects in Photoacoustic Spectroscopy." Applied Spectroscopy 55, no. 10 (October 2001): 1360–67. http://dx.doi.org/10.1366/0003702011953487.

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In Fourier transform infrared (FT-IR) photoacoustic spectroscopy, advanced scanning and data-handling techniques have placed increasing emphasis on the phase of the photoacoustic signal. Unfortunately, there is no agreement on the best material to use as a phase reference. We have examined the frequency dependence of the signal from several candidate phase references and found that cell effects dominate the absolute phases and magnitudes observed. The absolute phase is exceptionally fast at low frequencies and exceptionally slow at high frequencies because of the cell effects. Accordingly, details such as sample position must be scrupulously controlled to achieve accurate, reproducible results. Because of the cell effects, no candidate material behaves like an ideal phase reference. If relative phases are used, however, glassy carbon comes closest to the ideal, differing from theory by no more than 8° at any frequency examined.

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28

García, R. A., and P. L. Pallé. "High Frequency Signal in Golf Data." Symposium - International Astronomical Union 185 (1998): 447–48. http://dx.doi.org/10.1017/s0074180900239132.

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The analysis of ≈ 460 days of high quality data provided by the GOLF experiment on board SOHO, has unambiguously revealed the presence of signal in the power spectrum in the region 5.8 to 7.5 mHz, well above the p-modes cut-off frequency. In this contribution, the observed structure of these full-disk observations is presented. High frequency peaks (hereafter HFPs) well above the acoustic cutoff frequency of the solar p modes (≈ 5.5 mHz) have been already observed in intermediate and high spatial resolution oscillation data (Duvall et al. 1991). The different interpretations of the observed pattern (Kumar 1994 and references therein; Rast and Gough 1995) agree that it provides direct information on the location and some characteristics of the source of the acoustic oscillations (see also Vorontsov et al. 1997).

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29

Corkett, Michael. "The Quality of Canadian and U.S. Government Health Documents Remains Unchallenged Until Better Research Can Be Undertaken." Evidence Based Library and Information Practice 1, no. 4 (December 11, 2006): 74. http://dx.doi.org/10.18438/b8rc71.

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A review of: Lambert, Frank. “Assessing the Authoritativeness of Canadian and American Health Documents: A Comparative Analysis Using Informetric Methodologies.” Government Information Quarterly 22.2 (2005): 277-96. Objective - To assess by means of citation analysis whether the public trust afforded health documents published by the Canadian and U.S. governments is appropriate, and to ascertain whether differences in the respective health care systems influence how publications are produced. Design – Comparative study. Setting – The Canadian Depository Service Program (DSP) and the U.S. Department of Health and Human Services (DHHS) web sites. Subjects – One hundred sixty-six electronic documents sourced from the DSP website, and 284 electronic documents sourced from the DHHS website. Methods – Subjects were randomly selected from repositories offering the most comprehensive collections. Documents with evidence of references to other works used in preparation were separated from those without such characteristics. Data variables were collected from documents with evidence of references. Statistical analysis of the data was undertaken. Main results – Of the respective samples, 89 (53%) from the DSP and 109 (38.4%) from the DHHS contained references. Personal authors were identified in 46 (51.7%) and 63 (58%) of the respective subsets. Handbooks and guidebooks accounted for the largest portion of the DSP subset (29; 32.6%) and government periodicals were the largest constituent of the DHHS subset (41; 37.6%). Scholarly journals were the most common reference type for both the DSP (44%) and the DHHS (58.5%) subsets. The number of references per document was widely dispersed for both subsets; the DSP mean was approximately 64 (SD=114.68) and the DHHS was 73.71 (SD=168.85). Kruskal-Wallis subset analysis of median number of references by document type found differences generalizable to the entire DSP and DHHS populations. Health Canada Reports, handbooks, and guidebooks contained significantly more references than periodical articles or fact sheets. Certain DHSS documents, classified as “other,” contained more references than periodical articles. Canadian documents were more likely to contain references than U.S. documents. Comparison of documents to determine whether one country employs more rigorous citation practices did not produce statistically significant results. U.S. Federal Government documents are more likely to be referenced in other U.S. government health documents, compared to Canadian publications. The presence of references in documents from either country significantly affected likelihood of being cited by web authors. Conclusion – Significant differences in reference use frequencies between DSP and DHHS documents challenges Foskett’s stance that documents of value contain references (Foskett). Use of peer-reviewed scholarly journals for both DSP and DHHS publications was reassuring, suggesting a fairly rigorous publication standard. Reliance of DHHS publications upon federal government documents remains unclear. Referencing of DSP documents, irrespective of reference usage suggests a level of trust towards Canadian government health publications. Web authors appear more comfortable citing referenced DHHS documents. Further study could involve the examination of reference frequency by journal compared against journal impact factors.

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30

Han, Peiqing, Niansong Mei, and Zhaofeng Zhang. "Resistorless Frequency Locked On-Chip Oscillator with Proportional-to-Absolute Temperature References." Journal of Circuits, Systems and Computers 28, no. 10 (September 2019): 1950162. http://dx.doi.org/10.1142/s0218126619501627.

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A 36-kHz frequency locked on-chip oscillator is proposed, the proportional-to-absolute temperature (PTAT) current and voltage generator is presented to eliminate conventional temperature-compensated resistors. The resistorless approach reduces the process variation of frequency and the chip area. The oscillator is fabricated in 0.18-[Formula: see text]m standard CMOS process with an active area of 0.072[Formula: see text]mm2. The temperature coefficient of frequency is 48[Formula: see text]ppm/∘C at best and 82.5[Formula: see text]ppm/∘C on average over [Formula: see text]–70∘C and the frequency spread is 1.43% ([Formula: see text]/[Formula: see text] without calibration. The supply voltage sensitivity is 1.8%/V in the range from 0.65[Formula: see text]V to 1[Formula: see text]V and the power consumption is 95[Formula: see text]nW under the supply voltage of 0.65[Formula: see text]V.

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31

Wang, Chenchen, Natalie V. Wheeler, Coralie Fourcade-Dutin, Michael Grogan, Thomas D. Bradley, Brian R. Washburn, Fetah Benabid, and Kristan L. Corwin. "Acetylene frequency references in gas-filled hollow optical fiber and photonic microcells." Applied Optics 52, no. 22 (July 24, 2013): 5430. http://dx.doi.org/10.1364/ao.52.005430.

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32

Martinez de Escobar, Y. Natali, Silvana Palacios Álvarez, Simon Coop, Thomas Vanderbruggen, Krzysztof T. Kaczmarek, and Morgan W. Mitchell. "Absolute frequency references at 1529 and 1560 nm using modulation transfer spectroscopy." Optics Letters 40, no. 20 (October 13, 2015): 4731. http://dx.doi.org/10.1364/ol.40.004731.

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33

Bartels, A., S. A. Diddams, C. W. Oates, G. Wilpers, J. C. Bergquist, W. H. Oskay, and L. Hollberg. "Femtosecond-laser-based synthesis of ultrastable microwave signals from optical frequency references." Optics Letters 30, no. 6 (March 15, 2005): 667. http://dx.doi.org/10.1364/ol.30.000667.

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34

Gagliardi, G., G. Rusciano, and L. Gianfrani. "Narrow H218O lines and new absolute frequency references in the near-IR." Journal of Optics A: Pure and Applied Optics 2, no. 4 (June 23, 2000): 310–13. http://dx.doi.org/10.1088/1464-4258/2/4/312.

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35

Fischer, U. H. P., A. Gladisch, and L. Giehmann. "Comparison of Three Optical Frequency References for HDWDM Systems under Field Conditions." Optical Fiber Technology 2, no. 2 (April 1996): 179–82. http://dx.doi.org/10.1006/ofte.1996.0019.

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36

Zhao, Guan Qun, Ze Zhong Wang, Bo Dong, Li Li Zhao, and Ke Wang. "Suppression of High-Frequency Interference in Signal Loop." Applied Mechanics and Materials 713-715 (January 2015): 1081–85. http://dx.doi.org/10.4028/www.scientific.net/amm.713-715.1081.

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With the deep and promotion of unattended work in substations, the correct rate of remote signal becomes an important index in automation scheduling system. For remote signal false caused by high-frequency interferences in substation, we propose the use of Ni-Zn ferrite ring to suppress high-frequency interferences. The frequency-impedance characteristics of ferrite ring with different turns are tested. And the inhibitory effect of ferrite ring on interferences below and above 100MHz is measured separately. We installed ferrite rings in remote signal loops, and compared the voltage waveforms before and after installation. Experimental results provide some references to suppress high-frequency interferences by Ni-Zn ferrite ring.

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37

Aull, Bethany. "Pre-primary teacher talk: L1 use across different activity references." ELT Journal 75, no. 3 (April 19, 2021): 278–89. http://dx.doi.org/10.1093/elt/ccab013.

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Abstract Whether and how instructor L1 use may enhance foreign language learning has been a topic of considerable discussion. Although numerous studies note the L1’s recurrence in teacher talk, research has tended either to quantify its overall use throughout whole class sessions or to outline specific functions. Consequently, little is known about teachers’ actual L1-versus-L2 distribution across different classroom activities. This article contemplates teacher references relating to two prominent activities: core references (focusing on target content) and logistical references (classroom management and organisation). Via word count, it contrasts L1 use in the core and logistical references of ten non-native EFL instructors of very young learners. The findings indicate significantly higher L1 quantities in logistical than core references, even in the case of comprehensible high-frequency logistical terms such as sit. This disparity raises questions about the role of activity-differential L1 use, and points to the particular value of logistics for focalized teacher-talk analysis and awareness.

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38

Schuldt, Thilo, Klaus Döringshoff, Markus Oswald, Evgeny V. Kovalchuk, Achim Peters, and Claus Braxmaier. "Absolute laser frequency stabilization for LISA." International Journal of Modern Physics D 28, no. 12 (September 2019): 1845002. http://dx.doi.org/10.1142/s0218271818450025.

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The LISA space mission requires laser frequency pre-stabilization of the 1064[Formula: see text]nm laser sources. While cavity-based systems are the current baseline, laser frequencies stabilized to a hyperfine transition in molecular iodine near 532[Formula: see text]nm are a possible alternative. Several setups with respect to space applications were developed, putting special emphasis on compactness and mechanical and thermal stability of the optical setup. Vibration testing and thermal cycling were performed. These setups show frequency noise below 20[Formula: see text]Hz/[Formula: see text] for frequencies between 4[Formula: see text]mHz and 1[Formula: see text]Hz with an absolute frequency reproducibility better than 1[Formula: see text]kHz. They fulfil the LISA requirements and offer an absolute laser frequency simplifying the initial spacecraft acquisition procedure. We present the current status of iodine-based frequency references and their applicability in space missions, especially within the LISA mission.

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39

Affolderbach, C., and G. Mileti. "Tuneable, stabilised diode lasers for compact atomic frequency standards and precision wavelength references." Optics and Lasers in Engineering 43, no. 3-5 (March 2005): 291–302. http://dx.doi.org/10.1016/j.optlaseng.2004.02.009.

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40

Zhang, Zhen, Han Chen, and Peng Yan. "Internal model-based tracking of a servo gantry system with frequency-varying references." IFAC-PapersOnLine 49, no. 9 (2016): 39–44. http://dx.doi.org/10.1016/j.ifacol.2016.07.486.

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41

Xereas, George, and Vamsy P. Chodavarapu. "Ultraclean wafer-level vacuum-encapsulated silicon ring resonators for timing and frequency references." Journal of Micro/Nanolithography, MEMS, and MOEMS 15, no. 3 (September 9, 2016): 035004. http://dx.doi.org/10.1117/1.jmm.15.3.035004.

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42

Thorpe, Michael J., David R. Leibrandt, and Till Rosenband. "Shifts of optical frequency references based on spectral-hole burning in Eu3+:Y2SiO5." New Journal of Physics 15, no. 3 (March 6, 2013): 033006. http://dx.doi.org/10.1088/1367-2630/15/3/033006.

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43

Christoforou, Anthea, Naomi Dachner, Rena Mendelson, and Valerie Tarasuk. "Front-of-package nutrition references are positively associated with food processing." Public Health Nutrition 21, no. 1 (June 15, 2017): 58–67. http://dx.doi.org/10.1017/s1368980017001057.

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AbstractObjectiveFoods characterized by a high degree of processing are pervasive in the global food supply and concerns have been raised about their contribution to the escalating burden of diet-related disease. It has been suggested that the dominance of these products relates in part to their aggressive on-package marketing. The purpose of the present study was to assess the relationship between the extent and nature of front-of-package (FOP) nutrition references on products sold in Canadian supermarkets and the level of food processing.DesignFOP references were recorded from all packaged foods. Nutrition references were classified as ‘negative’ and ‘positive’ and further differentiated in terms of the use of regulated and unregulated text. Foods were coded for level of processing, using three different classification systems. Logistic and negative binomial regression analyses were conducted to assess associations.SettingThree large Toronto supermarkets, from the top Canadian food retailers.SubjectsPackaged foods (n 20 520).ResultsForty-one per cent of products had FOP nutrition references. Irrespective of the classification system considered, the most processed category comprised the greatest proportion of products and nearly half of these bore FOP references. Foods deemed most processed were more likely than less processed products to bear FOP references and regulated and unregulated references to negative ingredients, but they were equally or less likely to bear positive nutrition references, depending on the classification system.ConclusionsThe greater frequency of FOP nutrition references on heavily processed foods raises questions about the extent to which discretionary FOP labelling supports public health efforts to promote healthy eating.

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Li, Dan, Fu-Min Dai, Juan-Juan Xu, and Meng-Die Jiang. "Characterizing Hotspots and Frontier Landscapes of Diabetes-Specific Distress from 2000 to 2018: A Bibliometric Study." BioMed Research International 2020 (January 16, 2020): 1–13. http://dx.doi.org/10.1155/2020/8691451.

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Objectives. This work aims to comprehensively characterize hotspots and frontier landscapes concerning diabetes-specific distress from 2000 to 2018. Materials and Methods. Firstly, diabetes-specific distress-related literature was retrieved and downloaded from the Web of Science Core Collection (WoSCC). Secondly, WoSCC self-contained toolkits and GraphPad Prism7 were conducted to analyze general characteristics, including literature products, countries, institutes, authors, and journal resource. Finally, CiteSpace V Toolkits was put forward to implement advanced analysis, consisting of keyword-term frequency and co-occurrence, references-cited frequency and co-occurrence, and burst detection for keyword terms and references cited, which uncovers the hotspots and frontiers of diabetes-specific distress. Results. After preprocessing, our study included a total of 1051 papers concerning diabetes-specific distress. Publication outputs increased smoothly year by year. Compared with other journals, diabetic medicine delivered the largest number of documents. The United States occupied the leading positions, and the most productive institution was the University of California System in terms of literature products. Fisher L. has the highest references-cited frequency. Prevalence of diabetes-specific distress, diabetes-specific distress and glycemic control, diabetes-specific distress and depression comorbidity, and diabetes-specific distress and risk factors were the research hotspots, whereas the measure of diabetes-specific distress and latent and serious/severe diabetes-specific distress was the research frontiers. Conclusions. Overall, our study may inspire researchers to show great interest in diabetes-specific distress in the next few years.

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Tang, S. J., Q. Zhu, W. Chen, W. X. Wang, Y. Li, W. Darwish, and W. B. Li. "A FREQUENCY-DRIFT COMPENSATED CLOSED-FORM SOLUTION FOR STEREO RGB-D MAPPING." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences IV-2/W5 (May 29, 2019): 293–97. http://dx.doi.org/10.5194/isprs-annals-iv-2-w5-293-2019.

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<p><strong>Abstract.</strong> In this work, we present a frequency-drift compensated (Fd-C) closed-form solution for stereo RGB-D SLAM. The intrinsic parameters for each sensor are first obtained with a standard camera calibration process and the extrinsic orientation parameters achieved through a coarse-to-fine scheme that solves the initial exterior orientation parameters (EoPs) from control markers and further refines the initial value by an iterative closest point (ICP) variant minimizing the distance between the RGB-D point clouds and the referenced laser point clouds. With the assumption of fix transformation between the frames with the same timestamp, we define one sensor as reference sensor and the other sensor as slave sensor and the slave frames can be mapped to the timeline of the references sensor. Rather than endow the camera pose of the nearest frame to the slave frames, we derive the accurate camera pose for slave frames in a spatially variant way. Therefore, the pose relations between the slave frame and the adjacent reference frame can be derived, which provided opportunity to use the more accuracy observations from multiple frames for better tracking and global optimization. We present the mathematical analysis of the iterative optimizations for pose tracking in multi-RGB-D camera cases. Finally, the experiments in complex indoor scenarios demonstrate the efficiency of the proposed multiple RGB-D slam algorithm.</p>

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Peris-Mencheta Puch, L., M. C. Senín-Calderón, E. Fernández-Jiménez, S. Fuentes-Márquez, M. Valdés-Diaz, M. D. M. Benítez-Hernández, and J. F. Rodríguez-Testal. "Referential thinking and severe mental disorders." European Psychiatry 26, S2 (March 2011): 1212. http://dx.doi.org/10.1016/s0924-9338(11)72917-0.

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AntecedentsIn a previous study (Senín-Calderón et al., 2010) we observed that the REF scale of referential thinking (Lenzenweger et al., 1997) didn’t discriminate among different mental disorders.Objectives and hypothesesWe try to verify if self-references in various disorders are related to the severity of psychopathology (patients from public hospital and a private clinical). We predict that there will be differences between patients and controls, but not between the clinical samples. Psychotic disorders will be characterized by a significantly greater presence of self-references.MethodsParticipants: 287 subjects, 47 patients from a private clinical center, 57.4% women (mean age = 35.02, SD = 12.69), 30 patients from a public hospital, 53.3% women (38.36 years, SD = 9.53), and 210 controls selected from the general population, 50.5% women (33.80 years, SD = 11.79). Cross-sectional design, correlation method. All analysis were accepted at p < .05.ResultsThere are significant differences in self-references between patients and controls in frequency (t (285) = 2.33, p = . 021) and intensity (t (83.98) = 3.59, p = . 001). No significant differences between patients groups (p>.05) (REF-intensity without homogeneity, p < .05). No significant differences in self-references between types of diagnoses except psychotic patients versus adjustment disorder (frequency and intensity).ConclusionsSelf-references are highlighted in psychosis but, with the exception of adjustment disorders, doesn’t discriminate between personality, mood or anxiety disorders. Differences are more related to the clinical severity (BPRS) than with referential thinking.

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Oermann, Marilyn, Nancy Wilmes, and Patricia Braski. "Reference Accuracy in Neonatal-Maternal Nursing Literature." Neonatal Network 21, no. 1 (February 2002): 23–26. http://dx.doi.org/10.1891/0730-0832.21.1.23.

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Purpose: To identify the frequency and types of reference errors in neonatal-maternal nursing literature. This study was an extension of earlier research on reference accuracy in pediatric and critical care nursing journals.Design: A random sample was selected of references in three nursing journals: Neonatal Network: The Journal of Neonatal Nursing; Journal of Obstetric, Gynecologic, and Neonatal Nursing; and The American Journal of Maternal/Child Nursing. References were compared against original publications, and errors were classified as major or minor based on criteria used in earlier studies.Results: Fifty-four of the 221 references had errors, for an overall error rate of 24.4 percent. Major errors were found in 21.3 percent of the references, and minor errors were calculated at 3.2 percent. Errors in the author’s name were most common, followed by errors in titles of articles and books. The rates of reference errors in this study were lower than those reported previously in the nursing and medical literature.

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Cui, H., and G. Zhang. "HIGH-RESOLUTION OPTICAL SATELLITE IMAGES COLOR CONSISTENCY METHOD BASED ON EXTERNAL COLOR REFERENCES." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences V-3-2020 (August 3, 2020): 663–68. http://dx.doi.org/10.5194/isprs-annals-v-3-2020-663-2020.

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Abstract. Affected by factors such as season, illumination, atmospheric and sensor distortion, different satellite images often show obvious color difference, resulting in “stitching seams” at the edge of adjacent images, which seriously affects the application of satellite images. This study proposes a novel color consistency method for optical satellite images utilizing external color reference. Firstly, we improved the dark channel defogging method combining with the atmospheric distribution characteristics of satellite images, and used it to perform atmospheric correction on satellite images; Secondly, we corrected the color of atmospheric corrected satellite images through low-frequency signal replacement. Finally, we use a linear model to establish the relationship between high and low frequency signals, and stretching the high-frequency signal of images through local modelling. We selected two sets of representative experimental data for experiments, both the visual and quantitative obtained excellent results.

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Cai, Yanxia, Kai Zhang, Zhoujing Ye, Chang Liu, Kaiji Lu, and Linbing Wang. "Influence of Temperature on the Natural Vibration Characteristics of Simply Supported Reinforced Concrete Beam." Sensors 21, no. 12 (June 21, 2021): 4242. http://dx.doi.org/10.3390/s21124242.

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Natural vibration characteristics serve as one of the crucial references for bridge monitoring. However, temperature-induced changes in the natural vibration characteristics of bridge structures may exceed the impact of structural damage, thus causing some interference in damage identification. This study analyzed the influence of temperature on the natural vibration characteristics of simply supported beams, which is the most widely used bridge structure. The theoretical formula for the variation of the natural frequency of simply supported beams with temperature was proposed. The elastic modulus of simply supported beams in the range of −40 °C to 60 °C was acquired by means of the falling ball test and the theoretical formula and was compared with the elastic modulus obtained by the three-point bending test at room temperature (20 °C). In addition, the Midas/Civil finite-element simulation was carried out for the natural frequency of simply supported beams at different temperatures. The results showed that temperature was the main factor causing the variation of the natural frequency of simply supported beams. The linear negative correlation between the natural frequency of simply supported beams and their temperature were observed. The natural frequency of simply supported beams decreased by 0.148% for every 1 °C increase. This research contributed to the further understanding of the natural vibration characteristics of simply supported beams under the influence of temperature so as to provide references for natural frequency monitoring and damage identification of beam bridges.

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Zhao, Fang Ping, Yong Yang, and Yi Yuan. "Quasi Resonant Direct Power Control of Three-Phase Grid-Connected Inverters in Distributed Generation Systems." Applied Mechanics and Materials 48-49 (February 2011): 863–67. http://dx.doi.org/10.4028/www.scientific.net/amm.48-49.863.

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The paper proposes a quasi resonant direct power control algorithm for three-phase grid-connected inverters without grid voltage sensors in distributed generation systems. According to the active and reactive power references, grid virtual flux and the inverter output current references are calculated. In order to accurately and fast track the output current references, the quasi proportional resonant (QPR) controller is used. The theoretical principle of this method is discussed. The steady-state and dynamic experimental results of quasi resonant direct power control that can illustrate the operation and performance of the presented control strategy are displayed. It is shown that the control system exhibits several advantages, such as constant switching frequency, sinusoidal grid currents and good dynamic response. Experimental results are provided to demonstrate the effectiveness of the proposed control strategy.

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