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Artigos de revistas sobre o assunto "Two- or one-op-amp resonator"
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Ammar, Kholoud, Amr Hussein e Mahmoud Attia. "High space efficiency compact chipless RFID tag with equidistance resonances". International Journal of Engineering & Technology 7, n.º 2 (23 de abril de 2018): 609. http://dx.doi.org/10.14419/ijet.v7i2.9254.
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Radio Frequency Identification (RFID) technology provides non line-of-sight communication between the reader and the tag. This technology is widely used for various applications such as item tracking, security, access control, health care, short and long-range applications. RFID can be used as low cost data identification technology using radio waves between the RFID transmitter and the RFID receiver. Many attempts are introduced to implement the chipless RFID tags but they suffer from non-equal spacing between resonances which makes it difficult to make the decision. In this paper, compact low cost spectral signature based chipless 8-bits RFID tag is introduced. Multi dual-band resonating circuits with different resonances are used. The operation bandwidth is limited by the second resonance of the resonator. To avoid the presence of harmonics in the operating frequency range, multiple resonators with different shapes are introduced. The proposed tag instead of encoding only one data bit it encodes two data bits providing higher bits/resonator. The proposed tag provides equidistance between resonance frequencies. The tag is implemented on FR4 substrate of dielectric constant =4.4, thickness h=1.6mm and loss tangent δ=0.0018. The scattering parameters of the fabricated tags are measured using the vector network analyzer (ROHDE&SCHWARZ ZVB 20). The designs of the tags are made using the software package CST MICROWAVE STUDIO.
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Hussein, Majed, e Ilian Hristov. "Effect of Removable Complete Dentures on the Fundamental Frequency of Speech". Folia Medica 62, n.º 4 (31 de dezembro de 2020): 812–16. http://dx.doi.org/10.3897/folmed.62.e50718.
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Introduction: Removable complete dentures alter the spectrum of speech sounds by changing the elasto-plastic properties of certain areas of the oral cavity walls, and the geometric characteristics of the vocal resonator. These relationships predetermine largely the aims of conventional studies on the effect of prosthetic dentures on speech function. Aim: To investigate the effect removable dentures have on the fundamental frequency of speech during different stages of the adapta-tion period. Materials and methods: We analysed 96×2 digital sound recordings made by 64 patients (32 male and 32 female). Each patient was asked to say ‘three, two, one, zero, start’ three times: before denture placement, after denture placement, and after a two-week adaptation period. The pitch contours of F0 and the numeric values were obtained using the Speech Analyzer - SIL Language Technology software. Results: Immediately after denture placement, in male patients F0 increased by 12% on the average, and in female patients – by 10%. Two weeks after denture placement, F0 regained its normal value (p<0.05). The mean value of F0, whose raising can be interpreted as an acoustic correlate of temporary psychological stress, returned to normal after a brief adaptation period (in this case – 14 days). Conclusions: The results on the systematic changes of F0 in the course of the complete denture prosthetics are indicative for the systematic speech impediments before, and the absence of such impediments after (in case of successful prosthetics) the adaptation.
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Pedneault-Deslauriers, Julie. "Webern’s Angels". Journal of Musicology 32, n.º 1 (1 de janeiro de 2015): 78–114. http://dx.doi.org/10.1525/jm.2015.32.1.78.
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Anton Webern’s Two Songs, Op. 8 on Poems by Rainer Maria Rilke (1910-1926) stand at the intersection between the composer’s spiritual ideals involving a fascination for angels, his personal circumstances at the time of the songs’ composition, and the literary influences of Weininger, Balzac, and especially Rilke. The Lieder absorb the Rilkean notions of transcendence and “intransitive love,” themes developed in the novel The Notebooks of Malte Laurids Brigge, the source of Webern’s texts. According to Rilke, lovers access the higher spiritual realm of angels by forsaking (rather than yearning for) proximity and possession. This concept resonates with the relationship Webern crafts between the chamber orchestra and the vocal line, one that eludes the goals it projects and expresses quasi-intangible motivic connections that dematerialize as soon as they form. The Op. 8 songs represent a turning point that reverberated throughout Webern’s personal and spiritual life: the promise of transcendence that Rilke’s poems held was couched in terms that echoed the hardships and rewards of his relationship with his future wife and, at the same time, resonated with the composer’s religious and artistic morals.
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Azola, Alba, Jeffrey Palmer, Rachel Mulheren, Riccardo Hofer, Florian Fischmeister e W. Tecumseh Fitch. "The physiology of oral whistling: a combined radiographic and MRI analysis". Journal of Applied Physiology 124, n.º 1 (1 de janeiro de 2018): 34–39. http://dx.doi.org/10.1152/japplphysiol.00902.2016.
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The fluid mechanics of whistling involve the instability of an air jet, resultant vortex rings, and the interaction of these rings with rigid boundaries (see http://www.canal-u.tv/video/cerimes/etude_radiocinematographique_d_un_siffleur_turc_de_kuskoy.13056 and Meyer J. Whistled Languages. Berlin, Germany: Springer, 2015, p. 74–774). Experimental models support the hypothesis that the sound in human whistling is generated by a Helmholtz resonator, suggesting that the oral cavity acts as a resonant chamber bounded by two orifices, posteriorly by raising the tongue to the hard palate, and anteriorly by pursed lips (Henrywood RH, Agarwal A. Phys Fluids 25: 107101, 2013). However, the detailed anatomical changes in the vocal tract and their relation to the frequencies generated have not been described in the literature. In this study, videofluoroscopic and simultaneous audio recordings were made of subjects whistling with the bilabial (i.e., “puckered lip”) technique. One whistling subject was also recorded, using magnetic resonance imaging. As predicted by theory, the frequency of sound generated decreased as the size of the resonant cavity increased; this relationship was preserved throughout various whistling tasks and was consistent across subjects. Changes in the size of the resonant cavity were primarily modulated by tongue position rather than jaw opening and closing. Additionally, when high-frequency notes were produced, lateral chambers formed in the buccal space. These results provide the first dynamic anatomical evidence concerning the acoustic production of human whistling. NEW & NOTEWORTHY We establish a new and much firmer quantitative and physiological footing to current theoretical models on human whistling. We also document a novel lateral airflow mechanism used by both of our participants to produce high-frequency notes.
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Bryndin, Evgeniy. "Fiber Optic Network Technology of Communication of Specialists via Mental Neurointerfaces". Network and Communication Technologies 6, n.º 2 (30 de dezembro de 2021): 1. http://dx.doi.org/10.5539/nct.v6n2p1.
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Resonance communication of specialists can be carried out at a distance in real time in dialogue mode through a mental neurointerface with two-way communication. Mental neurointerface on the principles of magnetic resonance tomography captures a hologram of brain activity of the internal speech of the inductor specialist and transmits it to the mental neurointerface of the recipient's interlocutor through ultra-sensitive multi section nano resonators waveguides. The mental neurointerface of the recipient's interlocutor perceives the transmitted hologram of the brain activity of internal speech and resonates its internal speech to it. An interlocutor of the recipient with equivalent semantic memory in a resonant way makes sense of the internal speech of the inductor specialist. He forms the response with internal speech and transmits it to the interlocutor with his mental neurointerface through nano resonators in the form of holograms of the brain activity of internal speech. Interlocutors, as specialists in one subject area, have a similar semantic memory. Semantic memories are considered similar if they correspond to the principle of gold section according to a professional thesaurus. Specialists and interlocutors must learn a professional thesaurus before starting a dialogue through mental neurointerfaces. Thus, the problem of transmitting and reading thoughts at a distance using high technology is solved, taking into account the psychological aspects of the interlocutors. The development of mental neurointerfaces and ultra-sensitive multi section nano waveguide resonators for transmitting holograms of internal speech brain activity is just beginning. The use of resonant communication by mental neurointerfaces through nano waveguides resonators waveguides is currently very relevant in many areas of life activity.
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Goh, Shao Hung, e Stephen Eldridge. "New product introduction and supplier integration in sales and operations planning". International Journal of Physical Distribution & Logistics Management 45, n.º 9/10 (5 de outubro de 2015): 861–86. http://dx.doi.org/10.1108/ijpdlm-08-2014-0215.
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Purpose – The purpose of this paper is to investigate the implementation and performance benefits of sales and operations planning (S & OP) within organizations in Asia Pacific. Design/methodology/approach – A case study method was used, with two companies selected. The first company had recently commenced S & OP and applied it to facilitate new product introduction, while the second had integrated its supplier into an existing S & OP program. Supply chain performance data were collected and analyzed in the context of an S & OP maturity framework. Findings – Both cases show significant improvements in supply chain performance. In one case, the implementation of a common form of S & OP resulted in a 67 percent reduction in order lead time for newly introduced products. The second case demonstrated a 30 percent reduction in inventory levels and a 52 percent improvement in forecast accuracy through more advanced S & OP processes. Research limitations/implications – This paper studies just two companies and is not intended to be representative of outcomes at all companies implementing S & OP. Further studies are required for a more generalized picture of S & OP implementations in the Asia Pacific region to emerge. Practical implications – The findings illustrate the potential quantitative benefits of adopting S & OP and the circumstances under which these benefits may be achieved. The results are also supportive of the notion of a maturity model for S & OP implementations. Originality/value – This paper strengthens the link between practitioner and academic literature by providing empirical evidence of the benefits of S & OP. Furthermore, the findings are derived from the Asia Pacific region for which there have been few academic studies on S & OP to date.
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Li, TianYang. "Circuit Simulation of the Analog Computer and Proportional Controlled DC Motor Based on Op Amp". Advances in Engineering Technology Research 10, n.º 1 (11 de abril de 2024): 464. http://dx.doi.org/10.56028/aetr.10.1.464.2024.
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Operational amplifier(op-amp) is a building block of many analog circuits, nowadays it has been the most widely used device in various electronics instruments. In modern electronics design, op-amp has a special weightage due to its robust characteristics. In this paper, two applications of op amp are discussed. One is using op-amp to construct an analog computer for solving second order differential equation. Another is to build a proportional controlled DC motor which transfer input voltage into angle. By varying the proportional gain at 1, 5 and 15, different result is obtained by octave simulation using step response graph and pole-zero diagram.
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Son, Shannon L., Ashley E. Benson, Emily Hart Hayes, Akila Subramaniam, Erin A. S. Clark e Brett D. Einerson. "Outpatient Cervical Ripening: A Cost-Minimization and Threshold Analysis". American Journal of Perinatology 37, n.º 03 (20 de agosto de 2019): 245–51. http://dx.doi.org/10.1055/s-0039-1694791.
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Objective To evaluate cost of outpatient (OP) versus inpatient (IP) ripening with transcervical balloons, and determine circumstances in which each strategy would be cost saving. Study Design We created a decision model comparing OP and IP balloon ripening in term (≥37 weeks) singleton pregnancies with unfavorable cervix. We performed a cost-minimization analysis and threshold analyses comparing two OP ripening strategies (broad and limited use) to IP ripening from a health system perspective. Base case estimates of probability, utilization, and cost were derived from the literature. The primary outcome was incremental cost of OP versus IP ripening from a hospital perspective. One- and two-way sensitivity analyses explored uncertainty in the model. Results Both OP ripening strategies were cost saving compared with IP ripening: incremental cost −$228.40/patient with broad use and −$73.48/patient with limited use. OP ripening was no longer cost saving if hours saved on labor and delivery (L&D) were <3.5, insertion visit cost >$714, or facility cost/hour on L&D <$61. Two-way sensitivity analyses showed that OP ripening was cost saving under the most plausible clinical circumstances. Conclusion In patients with unfavorable cervix, OP transcervical balloon ripening was cost saving under a wide range of circumstances, particularly if OP ripening can shorten time spent on L&D by 3.5 hours.
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Kavya, K. Guru Sai, G. Nagasowmya, G. Ankitha, K. Bharathi, K. Reshma e M. Sharmila. "Analysis of Two Stage CMOS Operational Amplifier in 90nm CMOS Technology". International Journal for Research in Applied Science and Engineering Technology 12, n.º 2 (29 de fevereiro de 2024): 444–49. http://dx.doi.org/10.22214/ijraset.2024.58338.
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Abstract: Operational amplifier circuits are used in computation, instrumentation and other applications. Precision op-amps previously used in instrumentation are now-a-days being used in industrial and automotive applications. Hence, there always exists a need for better precision op-amps. It should operate under a wide temperature range. Nowadays, due to the industry trend of applying standard process technologies to implement both analog circuits and digital circuits on the same chip, Complementary Metal-Oxide Semiconductor (CMOS) technology has become dominant over bipolar technology for analog circuit design in a mixed-signal system. Two-stage Op-Amp is one of the most commonly used Op-Amp architectures. In this work an operational amplifier based on CMOS is presented whose input depends on its bias currents which is 20µA and designed using 180nm and 90nm technologies. In sub-threshold region due to unique behavior of the MOS transistors not only allows a designer to work at low voltages and it also allows operating at low input bias currents. Most CMOS Op-Amps are designed for specific on-chip applications and are only required to drive capacitive loads of a few pf. In this proposed work, design of a two stage fully differential CMOS operational amplifier is presented and simulations are carried out in 180nm and 90nm technologies for various parameters. The simulation is to be carried out using Cadence Virtuoso Tool.
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Elwakil, A. S., e A. M. Soliman. "Two Modified for Chaos Negative Impedance Converter Op Amp Oscillators with Symmetrical and Antisymmetrical Nonlinearities". International Journal of Bifurcation and Chaos 08, n.º 06 (junho de 1998): 1335–46. http://dx.doi.org/10.1142/s0218127498001030.
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Two sinusoidal oscillator circuits, that employ an operational amplifier (op amp) as a current negative impedance converter (CNIC), are modified for chaos using a nonlinear resistor of anti-symmetrical current-voltage characteristics formed by a junction field effect transistor (JFET) operating in the triode region. The internal op amp dominant pole is found to contribute significantly to the chaotic nature of one circuit while the other circuit develops different chaotic attractors when cubic and fifth power odd symmetrical nonlinearities are used. Mathematical models of the two generators are presented. Experimental laboratory results, circuit simulations and numerical simulations of the mathematical models well agree and are included.
Teses / dissertações sobre o assunto "Two- or one-op-amp resonator"
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Mahmoud, Doaa. "Convertisseur analogique-numérique de type Sigma-Delta Passe-Bande avec résonateurs à un et deux amplificateurs". Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS288.
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Le récepteur radio logicielle (SDR) est une technique prometteuse pour les futurs récepteurs adaptés à une variété de protocoles. Il numérise le signal RF directement en basse fréquence. Nous proposons un récepteur SDR basé sur un modulateur sigma-delta à temps continu passe-bande (CT BP ). Nous nous concentrons sur les résonateurs RC actifs pour diminuer la surface du circuit. Nous ciblons les applications au voisinage de 400 MHz, à savoir Advanced Research and Global Observation Satellite (ARGOS), Medical Implant Communication Service (MICS), Automobile Keyless system et Industrial, Scientific and Medical (ISM). Nous présentons une nouvelle comparaison détaillée entre le modulateur CT BP à résonateur à deux amplificateurs et le modulateur CT BP à résonateur à un amplificateur. Les deux modulateurs sont conçus à l'aide de transistors MOS en technologie FDSOI-28nm, où nous utilisons la polarisation du caisson pour compenser les variations de processus, de tension et de températureSoftware defined radio receiver is a promising technique for future receivers which provides a variety of protocols. It digitizes the RF signal directly to low-frequency. We propose an SDR receiver based on a bandpass sigma delta modulator. The most essential element is the loop filter, there are two main configurations, an LC tank resonator and an active RC resonator. We focus on the active RC resonators for a low chip area. We target applications in the vicinity of 400 MHz, namely Advanced Research and Global Observation Satellite, Medical Implant Communication Service. We introduce a new comparison between the two-op-amp resonator CT BP sigma delta modulator and the one-op-amp resonator CT BP sigma delta modulator. We study the sensitivity of the quality factor and the signal to noise ratio to the DC-gain op-amps in two-op-amp resonator sigma delta modulator. It also shows how, in one-op-amp resonator sigma delta modulator, the quality factor and the signal to noise ratio, are very sensitive to any variations in the capacitors values for limited DC-gain op-amps. We establish a mathematical model of the thermal-noise behaviour for two-op-amp resonator CT BP sigma delta modulator. This model matches the circuit simulator results with a good accuracy. Furthermore, we demonstrate that a high quality factor (>100) of the two-op-amp resonators can be achieved by selecting the proper value of the integrator gain at a moderate DC-gain op-amp (35dB). Both sigma delta modulators are designed using flipped-well devices on fully depleted silicon on insulator technology, where we use body biasing to compensate the process, voltage and temperature variations
Capítulos de livros sobre o assunto "Two- or one-op-amp resonator"
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zappalà, Pietro. "Editorial Problems in Mendelssohn’s Organ Preludes, Op. 37". In The Mendelssohns, 27–42. Oxford University PressOxford, 2002. http://dx.doi.org/10.1093/oso/9780198167235.003.0002.
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Abstract Felix Mendelssohn Bartholdy’s Three Preludes and Fugues for Organ, Op. 37 were published either in the last days of 1837 or at the beginning of 1838. As was customary at the time, the collection appeared simultaneously in two editions, by Breitkopf & Härtel in Germany and by Novello in England. A close comparison reveals that the two editions differ in many places, and although most variants are relatively minor and concern matters not particularly essential to the musical text, there are enough of them—more than one hundred in the preludes alone—to raise some important questions: Why are there so many differences between the two editions? How did these differences arise? Which edition offers the more reliable text? The editorial problems posed by Op. 37 preludes are exemplified in the primary sources.
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Careri, Enrico. "The Concertos". In Francesco Genminiani (1687–1762), 59–83. Oxford University PressOxford, 1993. http://dx.doi.org/10.1093/oso/9780198163008.003.0005.
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Abstract ‘GEMINIANI with all his harmonica! abilities, was so circumscribed in his invention, that he was obliged to have recourse to all the arts of musical cookery, not to call it quackery, for materials to publish.’ The charge that Burney levels against the composer refers to his alleged lack of imagination, which caused him to recycle the same compositions several times over. Indeed, if we exclude all his numerous elaborations and transcriptions, the musical output of Geminiani seems rather exiguous: two sets of violin sonatas (Opp. I and N), one of cello sonatas (Op. V), three of Concerti grossi (Opp. II, ill, and VII), The Inchanted Forrest, and the compositions published in his treatises. Nevertheless, the same reproof could be addressed to Corelli and several other contemporary composers of note. Burney’s irritation probably stemmed from the disproportion between the success of Geminiani in England, where he had no rivals in the instrumental domain and was considered the equal of Handel, and the reason for this same success, which was almost entirely connected with his Op. ill concertos. His other compositions, with few exceptions, were rarely performed and little appreciated; in contrast, his Op. ill enjoyed an extraordinarily wide circulation, which even rivalled that of the celebrated works of Corelli. ‘Handel, Geminiani & Corelli’, Burney notes elsewhere, ‘were the sole Divinities of my Youth, but I was drawn off from their exclusive worship before I was 20, by keeping company with travelled & heterodox gentlemen, who were partial to the Music of more modem composers whom they had heard in Italy.’ The openmindedness of the young Burney was an exception in contemporary English musical circles, which in the years around the middle of the eighteenth century remained faithful to Corelli and Geminiani and showed little interest in what was going on beyond the English Channel.
Trabalhos de conferências sobre o assunto "Two- or one-op-amp resonator"
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Miao, Min, Jingpeng Bu, Liwei Zhao, Yufeng Jin e Yangfei Zhang. "A Bulk Micromachined Tunable Dual-Mode Microwave Bandpass Filter on Coplanar Waveguide". In 2008 Second International Conference on Integration and Commercialization of Micro and Nanosystems. ASMEDC, 2008. http://dx.doi.org/10.1115/micronano2008-70023.
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This paper proposes a bulk micromachined bandpass filter on 0.5mm-thick Pyrex glass, whose operation is based on the splitting of the odd and even degenerate mode in a dual-mode resonator, with the addition of a perturbation element. In such a way, a filter may require only half resonators of a traditional one, resulting in a more compact configuration over those ever reported. A 4%-bandwidth bandpass filter centered at 17GHz was designed. The square-ring-like coplanar waveguide (CPW) act as a dual-mode resonator, and an open-circuited stub attached to the inner corner of the square-ring acts as the perturbation element and dominates the filter bandwidth. The two bulk-micromachined switches for tuning are placed symmetrically along the diagonal line. Since the electrical length of CPW is extended after being loaded by capacitive switches, both the degenerate resonating frequencies and the filter mid-band frequency are shifted downward. Theoretical formulas are derived for various actuation states of all the switches. The filter performance is analysed also using finite-element fullwave tools. A frequency shift of 0.6GHz is seen which is close to 0.58GHz obtained from analytical solutions. Both the original and tuned state come with satisfying microwave performance, i.e. low passband insertion-loss (< 0.5dB) and return-loss (< −15dB) and high stopband rejection. It is also shown that the simulated result is in good agreement with theoretical solutions. The bulk microfabrication is shown to be much simpler than surface micromachining conventionally used for RF MEMS switches. Since the bridge skeleton is Si, thermal mismatch between all-metal bridge and dielectric substrate is avoided, and reliability at elevated temperature is guaranteed or at least greatly improved. Besides, the p++ doped Si line patterned simultaneously with the microbridges, can also be used as a DC biasing resistor, which can eliminate the additional steps to fabricate the resistive alloy line. The tested results of the fabricated switch samples are also shown. The device may be a good candidate for novel Ku-band inter-scientific satellite communication or wireless networking.
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Karimi, Muhammad Akram, Muhammad Arsalan e Atif Shamim. "Digital Twin of Expensive Multiphase Flow Loop Test to Develop Next Generation of Production Technologies". In International Petroleum Technology Conference. IPTC, 2022. http://dx.doi.org/10.2523/iptc-22124-ea.
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Abstract Multiphase flow is frequently encountered in upstream O&G industry that has significant impact on the development of numerous production technologies such as multiphase flowmeter. Before the deployment of these technologies in an oil/gas field, the technologies are tested in a multiphase industrial flow loop test that emulates multiphase test conditions. This paper presents a digital twin of 2-phase flow (oil & water) as a low cost alternative to expensive multiphase flow test. We have adopted backward strategy to design the digital twin of multiphase flow. At first, we characterized our proprietary microwave water-cut (WC) meter in an industrial flow loop in variable test conditions. Then, multiple digital models of the flow regimes were built and tested on our microwave WC meter. One of those models (rotated zigzag) was able to accurately predict WC sensor response over full WC range in oil continuous as well as water continuous flow conditions under varying salinity levels. Two sets of responses have been recorded and compared – first obtained from the industrial flow loop trials and second from our EM simulation model. Key microwave resonator parameters such as resonant frequency (f0) and quality (Q) factor have been compared under varying conditions. The comparison suggests that f0 & Q-factor give higher sensitivity against WC in oil continuous and water continuous flow conditions respectively. Moreover, WC sensor performance was also compared under varying salinity conditions in the range of 20,000 ppm to 80,000 ppm and digital twin is able to successfully predict the sensor response in these conditions as well. Significant amount of resources are spent on setting desired flow condition such as flow regime, WC and required salinity level. Our proposed digital twin model is able to emulate all of these multiphase flow conditions at negligible cost. It can help develop & test new production technologies without requiring to spend huge amount of money on lengthy, complex and expensive multiphase flow loop tests.
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Poignand, Gaelle, Emmanuel Jondeau e Philippe Blanc-Benon. "Aerodynamic and Thermal Measurements in a Standing Wave Thermoacoustic Refrigerator". In ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting collocated with 8th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2010. http://dx.doi.org/10.1115/fedsm-icnmm2010-30672.
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Thermoacoustic refrigerators produce a cooling power from an acoustic energy. Over the last decades, these devices have been extensively studied since they are environment-friendly, robust and miniaturizable. Despite all these advantages, their commercialization is limited by their low efficiency. One reason for this limitation comes from the complex thermo-fluid process between the stack and the two heat exchangers which is still not sufficiently understood to allow for optimization. In particular, at high acoustic pressure level, vortex shedding can occur behind the stack as highlight by [Berson & al., Heat Mass Trans, 44, 10151023 (2008)]. The created vortex can affect heat transfer between the stack and the heat exchangers and thus, they can reduce the system performance. In this work, aerodynamic and thermal measurements are both conducted in a standing wave thermoacoustic refrigerator allowing investigation of vortex influence on the system performance. The proposed device consists on a resonator operated at frequency of 200 Hz, with hot and cold heat exchangers placed at the stack extremities. The working fluid is air at ambient temperature and atmospheric pressure. The aerodynamic field behind the stack is described using high-speed Particle Image Velocimetry. This technique allows the acoustic velocity field measurement at a frequency up to 3000 Hz. Thermal measurements consist on the acquisition of both the temperature evolution along the stack and the heat fluxes extracted at the cold heat exchanger. These measurements are performed by specific micro-sensors developed by MEMS technology. The combination of these two measurements should be helpful for the further understanding of the heat transfer between the stack and the heat exchangers.