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Journal articles on the topic 'Modulateur optique'

Author: Grafiati

Published: 4 June 2021

Last updated: 7 February 2022

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1

Remiens, D., F. Mallecot, J. P. Vilcot, and D. Decoster. "Modulateur electro-optique à onde guidée sur GaAs." Revue de Physique Appliquée 22, no. 11 (1987): 1581–84. http://dx.doi.org/10.1051/rphysap:0198700220110158100.

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2

Boyko, O., D. Reitze, S. Kazamias, T. A. Planchon, C. Valentin, and Ph Balcou. "Optimisation de la génération d'harmoniques d'ordre élevé à l'aide d'une optique adaptative et d'un modulateur acousto-optique." Journal de Physique IV (Proceedings) 127 (June 2005): 99–103. http://dx.doi.org/10.1051/jp4:2005127015.

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3

Cambon, Pierre, Jean-Louis de Bougrenet de la Tocnaye, and Michael Killinger. "Modulateurs spatiaux bistables à cristal liquide et à adressage optique pour le calcul optique." Journal de Physique III 1, no. 1 (January 1991): 45–67. http://dx.doi.org/10.1051/jp3:1991107.

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4

Zhaoguang Pang, Zhaoguang Pang, Jie Li Jie Li, Yanlei Gao Yanlei Gao, and Zhenjun Yang Zhenjun Yang. "Theoretical studies on optimum design of acousto-optic modulator using lithium niobate crystal." Chinese Optics Letters 13, s1 (2015): S11601–311603. http://dx.doi.org/10.3788/col201513.s11601.

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5

GRYBA, T., and J. E. LEFEBVRE. "MODULATEURS ACOUSTO-OPTIQUES À PUITS QUANTIQUES MULTIPLES." Le Journal de Physique IV 02, no. C1 (April 1992): C1–1133—C1–1136. http://dx.doi.org/10.1051/jp4:19921250.

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6

Jiang, Chao, Xiao Gang Chen, and Zhao Xu Liu. "Effect of Modulation Index of Mach-Zehnder Modulator on Single Sideband Radio over Fiber System." Advanced Materials Research 756-759 (September 2013): 2350–53. http://dx.doi.org/10.4028/www.scientific.net/amr.756-759.2350.

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The effect of the modulation index of Mach-Zehnder modulator on single sideband (SSB) radio over fiber (RoF) system is investigated, and two different data modulation schemes are considered. The quantitative results suggest that there exist an optimum modulation index, and the system performance could be improved if the data signal is modulated on only optical carrier or sideband.

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7

Liu, Zhao Xu, Xiao Gang Chen, and Chao Jiang. "Performance Evaluation of Optical Carrier Suppression Radio over Fiber System through Modulation Index Enhancement." Advanced Materials Research 756-759 (September 2013): 1190–93. http://dx.doi.org/10.4028/www.scientific.net/amr.756-759.1190.

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The performance of optical carrier suppression (OCS) radio over fiber (RoF) system is evaluated through tuning the modulation index of Mach-Zehnder modulator, and two different data modulation schemes are considered. The quantitative simulation results validate that there exist an optimum modulation index, and the system performance could be improved if the data signal is modulated on only one of two sidebands.

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8

Intes, X., B. Le Jeune, F. Pellen, Y. Guern, J. Cariou, and J. Lotrian. "Determination of optical properties of multiple-scattering media by using a coherent-modulated source." Journal of Optics 28, no. 5 (October 1997): 218–24. http://dx.doi.org/10.1088/0150-536x/28/5/008.

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9

Lohman, J. A. B., and J. Bulthuis. "Optimum delay in modulated echo difference spectroscopy." Journal of Magnetic Resonance (1969) 63, no. 3 (July 1985): 593–95. http://dx.doi.org/10.1016/0022-2364(85)90251-3.

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10

Mazur, M. M., L. I. Mazur, and V. E. Pozhar. "Optimum Configuration for Acousto-optical Modulator Made of KGW." Physics Procedia 70 (2015): 741–44. http://dx.doi.org/10.1016/j.phpro.2015.08.119.

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11

Braunstein, Matthew, and Robert Y. Levine. "Optimum beam configurations in tomographic intensity modulated radiation therapy." Physics in Medicine and Biology 45, no. 2 (December 22, 1999): 305–28. http://dx.doi.org/10.1088/0031-9155/45/2/305.

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12

Kanopoulos, N., and V. Makios. "A single-chip adaptive delta modulator with optimum performance." Integration 3, no. 4 (December 1985): 319–28. http://dx.doi.org/10.1016/0167-9260(85)90016-1.

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13

Dezfuli, Ali Abbasi, Arash Shokouhmand, Amir Hosein Oveis, and Yaser Norouzi. "Reduced complexity and near optimum detector for linear‐frequency‐modulated and phase‐modulated LPI radar signals." IET Radar, Sonar & Navigation 13, no. 4 (April 2019): 593–600. http://dx.doi.org/10.1049/iet-rsn.2018.5271.

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14

Mounaix, Mickaël, Hugo Defienne, and Sylvain Gigan. "Contrôle spatio-temporel de la lumière en milieux complexes." Photoniques, no. 92 (July 2018): 29–33. http://dx.doi.org/10.1051/photon/20189229.

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La diffusion de la lumière est souvent considérée comme un obstacle en optique, dont on souhaite s’affranchir. Alors que c’était encore inconcevable au début du siècle (il y a à peine 15 ans !), il est désormais possible de manipuler la lumière cohérente multidiffusée dans des échantillons complexes grâce aux modulateurs spatiaux de lumière. Cette nouvelle thématique, dite du « contrôle du front d’onde », s’avère très prometteuse pour l’imagerie en profondeur, mais également pour le contrôle de l’interaction lumière-matière en milieu désordonné.

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15

M. A. Eid, Mahmoud, Ashraf S. Seliem, Ahmed Nabih Zaki Rashed, Abd El-Naser A. Mohammed, Mohamed Yassin Ali, and Shaimaa S. Abaza. "Duobinary modulation/predistortion techniques effects on high bit rate radio over fiber systems." Indonesian Journal of Electrical Engineering and Computer Science 21, no. 2 (February 1, 2021): 978. http://dx.doi.org/10.11591/ijeecs.v21.i2.pp978-986.

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<span>The work has presented duobinary modulation and predistortion techniques for the radio over fiber system enhancement for achieving security level. Duobinary modulation technique has more compact modulated spectral linewidth with standard non return to zero modulation code. Different NRZ/RZ rectangle shape employed that are namely exponential rectangle shape (ERS), and Gaussian rectangle shape (GRS) for different transmission bit rates. Switching bias voltage, and switching RF voltage based LiNbO<sub>3</sub> modulator are changed to measure the performance parameters of the radio over fiber (RoF) system. Predistortion technique improves the linearity of transmitter amplifiers and it is considered as a power efficiency technique. The optimum values of the Q-factor, data error rate (BER), electrical power, signal gain, noise figure, and light signal/noise ratio are achieved with 8 Volt for both switching biases/switching RF signal at 100 GHz. Signal quality/BER and electrical power after the receiver enhancement ratio by using this technique at different RF signal frequencies. </span>

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16

Xiang Zhang and T. Miyoshi. "Optimum design of coplanar waveguide for LiNbO/sub 3/ optical modulator." IEEE Transactions on Microwave Theory and Techniques 43, no. 3 (March 1995): 523–28. http://dx.doi.org/10.1109/22.372096.

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17

Chen, Shu-Qiang, Yu-Xin He, and Pei-Da Ye. "Optimum design of an optical waveguide modulator in a fin line." Microwave and Optical Technology Letters 8, no. 4 (March 1995): 216–18. http://dx.doi.org/10.1002/mop.4650080414.

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18

Razzaghi, Mohsen, and Jalal Nazarzadeh. "Optimum pulse-width modulated patterns in induction motors using Walsh functions." Electric Power Systems Research 35, no. 2 (November 1995): 87–91. http://dx.doi.org/10.1016/0378-7796(95)00992-2.

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19

Mints, M. Ya, and V. N. Chinkov. "An optimum method of measuring the parameters of amplitude-modulated signals." Measurement Techniques 38, no. 1 (January 1995): 108–15. http://dx.doi.org/10.1007/bf00976757.

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20

Razzaghi, M., and J. Nazarzadeh. "Optimum pulse-width modulated patterns in induction motors using Walsh functions." Fuel and Energy Abstracts 37, no. 3 (May 1996): 194. http://dx.doi.org/10.1016/0140-6701(96)88709-1.

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21

Arias, Ricardo, Hernán Mediote, and Hernán Tacca. "Flash FPGA-Based Numerical Pulse-Width Modulator." Advances in Power Electronics 2011 (April 4, 2011): 1–6. http://dx.doi.org/10.1155/2011/215376.

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A pulse-width modulator to drive three-phase AC motors is described. It performs a numerical modulation technique, also known as optimum or calculated modulation, but, in order to reduce hardware resources, a hybrid approach merging that calculated modulation with proportional modulation is proposed. The modulator is tested in a flash-based field programmable gate array (FPGA) implementation.

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22

Devaux, F. "Optimum prechirping conditions of externally modulated lasers for transmission on standard fibre." IEE Proceedings - Optoelectronics 141, no. 6 (December 1, 1994): 363–66. http://dx.doi.org/10.1049/ip-opt:19941584.

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23

Agrawal, Govind P. "Chirp minimization and optimum biasing for current-modulated coupled-cavity semiconductor lasers." Optics Letters 10, no. 1 (January 1, 1985): 10. http://dx.doi.org/10.1364/ol.10.000010.

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24

Szalewicz, A., B. Strzelczyk, and A. Kubicz. "Modulatory effect of divalent metal cations on the phosphotyrosine activity of the frog liver acid phosphatase." Acta Biochimica Polonica 46, no. 1 (March 31, 1999): 217–21. http://dx.doi.org/10.18388/abp.1999_4200.

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Frog liver acid phosphatase hydrolyzes phosphotyrosine at acidic pH optimum. Mn2+, Ca2+ and Mg2+ (but not Zn2+) ions modulate this activity by shifting its pH optimum to physiological pH. This effect is not observed when p-nitrophenylphosphate is used as a substrate. Phosphoserine and phosphothreonine are not hydrolyzed under the same conditions.

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25

Berolo, O. "Frequency-shift keyed generation with an optically controlled GaAs field-effect transistor in a surface-acoustic-wave oscillator circuit." Canadian Journal of Physics 65, no. 8 (August 1, 1987): 929–36. http://dx.doi.org/10.1139/p87-146.

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A prototype circuit for potential optical integration was developed and evaluated for the generation of frequency-shift keyed (FSK) signals by simultaneously exploiting surface-acoustic wave (SAW) technology and the optical response of the GaAs field-effect transistor (FET).A SAW delay line to be utilized in the feedback path of an oscillator circuit was designed for operation at the fundamental frequency of 111 MHz and operated at its 12th harmonic (1.33 GHz). A low-noise FET was incorporated into the circuit in series with the SAW delay, and a low-power He:Ne laser was focussed through an optical modulator onto the FET structure. The gate bias, which controls the phase shift in the feedback loop of the oscillator, was applied via the open-circuit photovoltage induced at the Schottky-barrier junction of the FET.The optical modulator was driven by a pseudorandom bit generator to obtain FSK generation by the oscillator circuit. Results of the frequency spectrum of the oscillator signal as a function of bit rate and light intensity on the FET were obtained. The successful performance of the circuit indicated that integration of all these elements on GaAs would yield a useful device for FSK signal generation.Un prototype de circuit pour intégration optique potentielle a été développé et évalué pour la génération de signaux FSK (frequency-shift keyed), en exploitant simultanéement la technologie des ondes acoustiques de surface et la réponse optique du transistor GaAs à effet de champ.

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26

Hao Yaohong, 郝耀鸿, 李玉权 Li Yuquan, and 王荣 Wang Rong. "Optimum Design for Optical Modulator in Coherent Optical Orthogonal Frequency-Division Multiplexing System." Chinese Journal of Lasers 38, no. 3 (2011): 0305003. http://dx.doi.org/10.3788/cjl201138.0305003.

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27

Tipping, A. K., G. Parry, and A. J. Moseley. "Modelling the optimum performance of InGaAs/InP-based asymmetric Fabry-Perot modulator devices." Semiconductor Science and Technology 5, no. 6 (June 1, 1990): 525–29. http://dx.doi.org/10.1088/0268-1242/5/6/010.

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28

Gayan, Samiru, Rajitha Senanayake, Hazer Inaltekin, and Jamie Evans. "Low-Resolution Quantization in Phase Modulated Systems: Optimum Detectors and Error Rate Analysis." IEEE Open Journal of the Communications Society 1 (2020): 1000–1021. http://dx.doi.org/10.1109/ojcoms.2020.3010514.

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29

Christenson, K. K. "Making optimum use of the signal in image digitization." Proceedings, annual meeting, Electron Microscopy Society of America 45 (August 1987): 100–101. http://dx.doi.org/10.1017/s0424820100125439.

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The detectors on modern electron microscopes often have a very high bandwidth which makes their outputs appear noisy on a short time scale. This noise is not a problem when photographing an image because the film integrates the signal. But it causes an annoying blurring of the trace in slow y-modulated line scans and can result in large errors if the signal is measured with a fast analog to digital converter (ADC)(Figs, 1,2).The noise in digital measurements can be reduced by reading the detector may times and taking the numerical average of the readings. This requires no extra hardware but it increases the time required to acquire a linescan or image and ignores the fundamental problem that the ADC wastes most of the information available in the signal by only sampling for a very small portion of its total cycle time.

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30

Hirakawa, Takashi, Ce Wang, and Naoki Shinohara. "RF-DC conversion efficiency improvement for microwave transmission with pulse modulation." Wireless Power Transfer 6, no. 1 (March 2019): 57–66. http://dx.doi.org/10.1017/wpt.2019.3.

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Microwave power transfer (MPT) can solve certain types of problems. For example, Internet of Things requires a flexible configuration of sensor networks, which is hindered by wired-charging sensors. This problem can be overcome by MPT techniques. However, the transmission efficiency of MPT is lower than that of wired transmission. This study focuses on the operation of rectifiers having a pulse-modulated input signal. Although a pulse-modulated wave is effective for improving the RF-DC conversion efficiency, the output voltage waves of rectifiers have a high ripple content. Moreover, the harmonic balance method cannot be used to simulate the operation of a pulse-modulated rectifier. To reduce the ripple content, a smoothing capacitor should be connected in parallel to an output load. We investigated the influence of a smoothing capacitor, the general characteristics of rectifiers under pulse-modulated waves, and the effectiveness of using pulse-modulated waves for improving RF-DC conversion efficiency. In conclusion, we reveal a necessary condition of the smoothing capacitor for improvement, demonstrate the effectiveness of pulse modulation, and show that the optimum impedance with a pulse-modulated wave input is an inverse of duty ratio times as compared to that with continuous wave input.

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31

WEI Liping, 韦丽萍, 王永华 WANG Yonghua, 臧俊斌 ZANG Junbin, 崔丹凤 CUI Danfeng, 李艳娜 LI Yanna, 刘耀英 LIU Yaoying, and 薛晨阳 XUE Chenyang. "Analysis and Optimum Design of Silicononinsulator Microring Resonator Electrooptic Modulator." ACTA PHOTONICA SINICA 42, no. 12 (2013): 1473–77. http://dx.doi.org/10.3788/gzxb20134212.1473.

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32

Webster, Gareth J., Carl G. Rowbottom, and Ranald I. Mackay. "Development of an optimum photon beam model for head-and-neck intensity-modulated radiotherapy." Journal of Applied Clinical Medical Physics 8, no. 4 (September 2007): 129–38. http://dx.doi.org/10.1120/jacmp.v8i4.2711.

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33

Sadat Noori, Seyed Ali, Ebrahim Farshidi, and Sirus Sadoughi. "A novel structure of dithered nested digital delta sigma modulator with low-complexity low-spur for fractional frequency synthesizers." COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering 35, no. 1 (January 4, 2016): 157–71. http://dx.doi.org/10.1108/compel-05-2015-0181.

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Purpose – Digital Delta Sigma Modulator (DDSM) is used widely in electronic circuits including Radars, class-D power amplifiers and fractional frequency synthesizers. The purpose of this paper is to propose an implementation for MASH DDSMs named as Multi Modulus Reduced Complexity (MMRC) architecture. Design/methodology/approach – This architecture will use a very simple pseudorandom Linear Feedback Shift Register (LFSR) dither signal with period N_d to randomize the digital MMRC modulator used for fractional frequency synthesizers. Using error masking methodology, the MMRC modulator can decrease the hardware consumption and increase accuracy of the fractional frequency synthesizer. Rules for selecting the appropriate word lengths of the constituent MMRC modulator are derived. Findings – This paper contains three modulators. The first stage modulator is a variable modulus First Order Error Feedback Modulator and has a programmable modulus M1 that is not a power of two. The second and third stage modulators are the first order pseudorandom LFSR dithered MASH 1-1 and modified MASH 1-1-1, which have conventional modulo M2, M3, respectively. With optimum selection modulus M1, the new structure can synthesize the desired frequency exactly. Simulation results confirm the theoretical predictions. Also the results of circuit implementation proposed method reports 13 per cent reduction in hardware. Originality/value – This paper for the first time proposes a nested sigma delta modulator with a pseudorandom shaped dither signal which reduced hardware complexity and increased the period of output signal. This modulator is exploited in the fractional frequency synthesizer to the output frequency can be set more accurately.

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34

Kaushik, Prashant, and Dinesh Kumar Saini. "Silicon as a Vegetable Crops Modulator—A Review." Plants 8, no. 6 (May 31, 2019): 148. http://dx.doi.org/10.3390/plants8060148.

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Vegetables require an optimum supply of mineral elements like silicon (Si). Si is second to oxygen in its abundance in the earth crust, and its role is quite significant in tackling biotic and abiotic stresses of vegetables. Si application also improves several agronomic and quality traits of vegetables. Hence, Si application is recommended as a strategy for the improvement of vegetable crops production. Although the research about the role of Si in vegetable dicots still lags far behind than cereals. Recently, omics-based approaches were used to provide a deeper understanding of the role of Si in vegetable protection. Here, we have compiled the studies focusing on the role of Si for vegetables, thus, enabling all of the important information regarding the effect Si application to vegetables at one place.

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35

Mainaji Amlogu, Abraham. "Supplementation of Optimum Nutrient-Dense Formula to Modulate HIV Infection in Resource Limited Settings." American Journal of Biomedical Science & Research 5, no. 1 (September 9, 2019): 73–75. http://dx.doi.org/10.34297/ajbsr.2019.05.000878.

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36

Al-Ithawi, Sabah, Wasan A. Hekmat, Kadhim A. Hubeatir, Shams B. Ali, Suad M. Kadhim, and Mohammed S. Hamza. "Characterization of Bulk BaTiO₃ Material for Optical Modulator Applications." Materials Science Forum 1002 (July 2020): 132–39. http://dx.doi.org/10.4028/www.scientific.net/msf.1002.132.

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In this work, different sizes of BaTiO3 (BTO) were characterized. The effective parameters were studied to reach optimum performance in order to realize an optical modulator. The parameters such as spectroscopy, electro-optic coefficient, crystalline structure, and birefringence indicated that BaTiO3 has an excellent behavior to manipulate the light by Pockels modulator, spatially in the field of telecom. The sample size (10×3 mm) was shown a good performance compare with other samples, for example, the BTO has low absorption, high variation of output as a function of voltage applied and good efficiency that showed by figure of merit. In addition, a low half-wave voltage (Vπ) was observed.

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37

Stepins, Deniss. "Conducted EMI of Switching Frequency Modulated Boost Converter." Electrical, Control and Communication Engineering 3, no. 1 (August 1, 2013): 12–18. http://dx.doi.org/10.2478/ecce-2013-0009.

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Abstract In this paper conducted electromagnetic interference (EMI) of boost converter with switching frequency modulation (SFM) is theoretically analyzed in details. In the analysis line impedance stabilization network parameters, power inductor and input filtering capacitor parameters are taken into account. The analysis shows that the conducted EMI attenuation due to the use of SFM depends not only on modulation index as it is assumed in numerous research papers, but also on central switching frequency. Useful expressions to numerically calculate SFM boost converter conducted EMI spectrum and attenuation due to the use of triangular and sawtooth modulation waveforms are derived. Additionally experimental verification of the theoretical results is performed using a superheterodyne spectrum analyzer. Moreover a procedure for the choice of optimum SFM parameters (modulation waveform, frequency deviation and modulation frequency) to get maximum conducted EMI attenuation is proposed.

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38

Paterson, Gordon G., Jason M. Young, Joseph A. Willson, Christopher J. Graham, Rebecca C. Dru, Eleanor W. Lee, Greig S. Torpey, et al. "Hypoxia Modulates Platelet Purinergic Signalling Pathways." Thrombosis and Haemostasis 120, no. 02 (December 13, 2019): 253–61. http://dx.doi.org/10.1055/s-0039-3400305.

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Abstract Background Hypoxia resulting from ascent to high-altitude or pathological states at sea level is known to increase platelet reactivity. Previous work from our group has suggested that this may be adenosine diphosphate (ADP)-specific. Given the clinical importance of drugs targeting ADP pathways, research into the impact of hypoxia on platelet ADP pathways is highly important. Methods Optimul aggregometry was performed on plasma from 29 lowland residents ascending to 4,700 m, allowing systematic assessment of platelet reactivity in response to several platelet agonists. Aggregometry was also performed in response to ADP in the presence of inhibitors of the two main ADP receptors, P2Y1 and P2Y12 (MRS2500 and cangrelor, respectively). Phosphorylation of vasodilator-stimulated phosphoprotein (VASP), a key determinant of platelet aggregation, was analysed using the VASPFix assay. Results Hypobaric hypoxia significantly reduced the ability of a fixed concentration of cangrelor to inhibit ADP-induced aggregation and increased basal VASP phosphorylation. However, in the absence of P2Y receptor inhibitors, we did not find evidence of increased platelet sensitivity to any of the agonists tested and found reduced sensitivity to thrombin receptor-activating peptide-6 amide. Conclusion Our results provide evidence of increased P2Y1 receptor activity at high altitude and suggest down-regulation of the P2Y12 pathway through increased VASP phosphorylation. These changes in ADP pathway activity are of potential therapeutic significance to high-altitude sojourners and hypoxic sea level patients prescribed platelet inhibitors and warrant further investigation.

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39

Jyumonji, Masayuki, Yoshinobu Kimura, Yukio Taniguchi, Masato Hiramatsu, Hiroyuki Ogawa, and Masakiyo Matsumura. "Optimum Light Intensity Distribution for Growing Large Si Grains by Phase-Modulated Excimer-Laser Annealing." Japanese Journal of Applied Physics 43, no. 2 (February 10, 2004): 739–44. http://dx.doi.org/10.1143/jjap.43.739.

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40

Yang, J., and B. Geller. "Near Optimum Low Complexity Smoothing Loops for Dynamical Phase Estimation—Application to BPSK Modulated Signals." IEEE Transactions on Signal Processing 57, no. 9 (September 2009): 3704–11. http://dx.doi.org/10.1109/tsp.2009.2021452.

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41

Wang, Ming Ming, and Ren Xian Li. "Analysis of Optimum Valve Timing Based on Diesel Engine Comprehensive Performance." Advanced Materials Research 347-353 (October 2011): 4118–24. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.4118.

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In order to investigate the effect of variable valve timing on engine power performance, fuel economy performance and emission performance quantitatively, proceed to optimize it, a high speed diese Specific Fuel Consumption, quantity of NOx and Soot, mass of fresh charge were calculated by 3-D CFD method l engine contains variable valve timing system (VVT) was researched. The effective power, at 6 speeds conditions which valve timing parameters were modulated. A method of calculating CRG was suggested. The results indicate that exhaust advance angle has a little impact on sweep and emission performance, but a big impact on ventilation losses. The optimum exhaust advance angle should be increased as engine speed rises. Increasing intake lag angle in low engine speed could increase coefficient of charge, thereby increase power performance and fuel economy performance. Comprehensive performance could be increased by decreasing intake delay angle under high speed.

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42

Hu, Min, and Ying Liu. "The Research of Modulation Period on Photoelectric Properties of Ti/TiN Multilayer Films." Advanced Materials Research 126-128 (August 2010): 935–39. http://dx.doi.org/10.4028/www.scientific.net/amr.126-128.935.

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A series of Ti/TiN multilayer films were prepared by reactive DC magnetron sputtering onto Si(111) substrates. The resistivity and optical reflectance of these thin films were measured as a function of the modulated, multilayered thickness and the number of layered structures. The resistivity decreased with increase in the number of layers in the film up to 4 layers. The reflectance in the near infrared region increased with increase in layer thickness but after a certain thickness, the change in reflectance was minimal. An optimum thickness of 25 nm for the modulated film realized a maximum of 0.829 in the near infrared reflectance. With the number of layers greater than 15, an interfacial layer of Ti2N was observed.

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43

Wang, Xia Xiao, Xi Chen Wang, and Xiu Juan Feng. "Digital Closed Loop Fiber-Optic Current Sensor Based on Integrated Optical Phase Modulator." Applied Mechanics and Materials 300-301 (February 2013): 427–31. http://dx.doi.org/10.4028/www.scientific.net/amm.300-301.427.

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The paper presents digital closed loop fiber-optic current sensor (FOCT)’s optical path which combines integrated optical modulator and polarization beam splitter as optimum combination, as well as numerical analysis on insertion loss of traditional optical path scheme which consists of straight waveguide and optical path proposed by ABB. It shows that loss causes equivalent noise current which will affect the sensitivity of photo detector. The calculation and experiment confirm that loss of optical path is an important factor for FOCT’s sensitivity, and optical path composed of integrated optical phase modulator with Y-Branch profile and polarization beam splitter can effectively reduce the insertion loss and improve sensitivity of the system.

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44

Gahley, Ruchi, and Banani Basu. "A Time Modulated Printed Dipole Antenna Array for Beam Steering Application." International Journal of Antennas and Propagation 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/3687293.

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This paper presents time modulated beam steered antenna array without phase shifters. The beam steering is analyzed considering a two-element time modulated antenna array (TMAA) of printed dipoles with microstrip via-hole balun. The proposed array resonates at the Industrial, Scientific, and Medical (ISM) radio bands, 2.45 GHz and 5.8 GHz, and offers wide bandwidth inherited due to modified structure of ground plane. Array elements are excited by complex exponential excitation signal through broadband power divider and radio frequency (RF) switches to achieve amplitude and phase variation without phase shifters. Differential Evolution algorithm is used to modify the time sequences of the RF switches connected to the antennas to generate radiation pattern with optimum dynamic efficiency by suppressing sideband radiations. Also switch-on time instant of RF switch connected to the subsequent element is modulated to steer the beam towards different directions. The proposed prototype is fabricated followed by parametric optimization. The fabrication results agree significantly well with simulated results.

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Karvelas, Evangelos, Christos Liosis, Theodoros Karakasidis, and Ioannis Sarris. "Micromixing Nanoparticles and Contaminated Water Under Different Velocities for Optimum Heavy Metal Ions Adsorption." Environmental Sciences Proceedings 2, no. 1 (September 8, 2020): 65. http://dx.doi.org/10.3390/environsciproc2020002065.

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Effective mixing between contaminated water and nanoparticles is of great importance in various purification applications of microfluidics, especially when heavy metals are involved. Electromagnetic and shear mixing is combined here to explore optimization mixing strategies. A contaminated water stream is confined between two fresh-water streams loaded with nanoparticles and their mixing is studied numerically. The magnetic mixing is superimposed here with a time-modulated gradient external magnetic field. Results show that as velocity ratio increases, mixing between the heavy metals and nanoparticles grows more efficient, mainly due to increased shear, however, magnetic field action is catalytic to homogenise the mixture as water streams move away from the inlets. The present findings may shorten the path to purifying water and reduce its shortage.

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Yavuz, Gürcan, and Doğan Aydin. "Angle Modulated Artificial Bee Colony Algorithms for Feature Selection." Applied Computational Intelligence and Soft Computing 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/9569161.

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Optimal feature subset selection is an important and a difficult task for pattern classification, data mining, and machine intelligence applications. The objective of the feature subset selection is to eliminate the irrelevant and noisy feature in order to select optimum feature subsets and increase accuracy. The large number of features in a dataset increases the computational complexity thus leading to performance degradation. In this paper, to overcome this problem, angle modulation technique is used to reduce feature subset selection problem to four-dimensional continuous optimization problem instead of presenting the problem as a high-dimensional bit vector. To present the effectiveness of the problem presentation with angle modulation and to determine the efficiency of the proposed method, six variants of Artificial Bee Colony (ABC) algorithms employ angle modulation for feature selection. Experimental results on six high-dimensional datasets show that Angle Modulated ABC algorithms improved the classification accuracy with fewer feature subsets.

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Heni, Wolfgang, Christian Haffner, Delwin L. Elder, Andreas F. Tillack, Yuriy Fedoryshyn, Raphael Cottier, Yannick Salamin, et al. "Nonlinearities of organic electro-optic materials in nanoscale slots and implications for the optimum modulator design." Optics Express 25, no. 3 (February 1, 2017): 2627. http://dx.doi.org/10.1364/oe.25.002627.

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Leer, Coretta Van, Monika Stutz, André Haeberli, and Thomas Geiser. "Urokinase plasminogen activator released by alveolar epithelial cells modulates alveolar epithelial repair in vitro." Thrombosis and Haemostasis 94, no. 12 (2005): 1257–64. http://dx.doi.org/10.1160/th05-03-0162.

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SummaryIntra-alveolar fibrin is formed following lung injury and inflammation and may contribute to the development of pulmonary fibrosis. Fibrin turnover is altered in patients with pulmonary fibrosis, resulting in intra-alveolar fibrin accumulation, mainly due to decreased fibrinolysis. Alveolar type II epithelial cells (AEC) repair the injured alveolar epithelium by migrating over the provisional fibrin matrix. We hypothesized that repairing alveolar epithelial cells modulate the underlying fibrin matrix by release of fibrinolytic activity, and that the degree of fibrinolysis modulates alveolar epithelial repair on fibrin. To test this hypothesis we studied alveolar epithelial wound repair in vitro using a modified epithelial wound repair model with human A549 alveolar epithelial cells cultured on a fibrin matrix. In presence of the inflammatory cytokine interleukin-1β, wounds increase by 800% in 24 hours mainly due to detachment of the cells, whereas in serum-free medium wound areas decreases by 22.4 ± 5.2 % (p<0.01). Increased levels of D-dimer, FDP and uPA in the cell supernatant of IL-1β-stimulated A549 epithelial cells indicate activation of fibrinolysis by activation of the plasmin system. In presence of low concentrations of fibrinolysis inhibitors, including specific blocking anti-uPA antibodies, alveolar epithelial repair in vitro was improved, whereas in presence of high concentrations of fibrinolysis inhibitors, a decrease was observed mainly due to decreased spreading and migration of cells. These findings suggest the existence of a fibrinolytic optimum at which alveolar epithelial repair in vitro is most efficient. In conclusion, uPA released by AEC alters alveolar epithelial repair in vitro by modulating the underlying fibrin matrix.

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Caliandro, Rocco, Pietro Guccione, Giovanni Nico, Goknur Tutuncu, and Jonathan C. Hanson. "Tailored multivariate analysis for modulated enhanced diffraction." Journal of Applied Crystallography 48, no. 6 (October 21, 2015): 1679–91. http://dx.doi.org/10.1107/s1600576715017070.

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Modulated enhanced diffraction (MED) is a technique allowing the dynamic structural characterization of crystalline materials subjected to an external stimulus, which is particularly suited forin situandoperandostructural investigations at synchrotron sources. Contributions from the (active) part of the crystal system that varies synchronously with the stimulus can be extracted by an offline analysis, which can only be applied in the case of periodic stimuli and linear system responses. In this paper a new decomposition approach based on multivariate analysis is proposed. The standard principal component analysis (PCA) is adapted to treat MED data: specific figures of merit based on their scores and loadings are found, and the directions of the principal components obtained by PCA are modified to maximize such figures of merit. As a result, a general method to decompose MED data, called optimum constrained components rotation (OCCR), is developed, which produces very precise results on simulated data, even in the case of nonperiodic stimuli and/or nonlinear responses. The multivariate analysis approach is able to supply in one shot both the diffraction pattern related to the active atoms (through the OCCR loadings) and the time dependence of the system response (through the OCCR scores). When applied to real data, OCCR was able to supply only the latter information, as the former was hindered by changes in abundances of different crystal phases, which occurred besides structural variations in the specific case considered. To develop a decomposition procedure able to cope with this combined effect represents the next challenge in MED analysis.

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Jordan, Nicholas. "Weed Demography and Population Dynamics: Implications for Threshold Management." Weed Technology 6, no. 1 (March 1992): 184–90. http://dx.doi.org/10.1017/s0890037x00034540.

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Threshold weed management methods have recently been elaborated to consider effects of threshold management on weed population dynamics. Such economic optimum thresholds are calculated using population-dynamics models which require detailed information about weed demography, including seed production (as affected by events between germination and seed dispersal), seed dispersal, and seed survival and movement in soil. Factors affecting any of these aspects of demography appear likely to modulate the growth rate of a sub-threshold population and therefore to influence the economic optimum threshold value. To test this conjecture and evaluate weed threshold management, including associated risk, improved understanding is particularly needed of weed seed dispersal, seedbank processes, and unpredictable demographic variation.

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