Relevant bibliographies by topics / Maximum pulse frequency

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  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Maximum pulse frequency'

Author: Grafiati
Published: 28 May 2022
Last updated: 30 July 2025

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Journal articles on the topic "Maximum pulse frequency"

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Jiang Pei-heng, Shi Chao-du, Fu Shi-jie та ін. "130 μJ linear-polarized single-frequency 12-μm-core Er/Yb co-doped fiber amplifier based on pre-shaped seed pulse". Acta Physica Sinica 74, № 2 (2025): 0. https://doi.org/10.7498/aps.74.20241371.

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Stimulated Brillouin scattering (SBS) is the major barrier in the process of energy scaling for pulsed single-frequency fiber MOPA. Due to gain saturation effect, the laser pulse profile will be gradually distorted with the increase of pump power, which induces steep leading edge and narrower width for the amplified pulses. The resulting laser peak power would increase rapidly and thus the SBS threshold is reached earlier to limit the amplification of pulse energy.<br>A method to obtain high-energy pulsed single-frequency laser by pulse pre-shaping is demonstrated in this work. By design
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Luiker, Eric A., and E. Don Stevens. "Effect of stimulus frequency and duty cycle on force and work in fish muscle." Canadian Journal of Zoology 70, no. 6 (1992): 1135–39. http://dx.doi.org/10.1139/z92-159.

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Stimulus trains of varying pulse number and pulse frequency were applied to the isolated pectoral adductor muscle of the sunfish Lepomis gibbosus. The number of pulses varied from 1 to 70, and the pulse frequency varied from 10 to 500 Hz. Muscle was continuously cycled at 2 Hz, and work was measured directly. Maximum force (177 kN/m2) was achieved with a train of 30 pulses at 169 Hz. Maximum work of 9.1 J/kg (power of 18.2 W/kg) was achieved with a train of 30 pulses at 169 Hz and a duty cycle (fraction of the cycle during which the muscle is activated) of 35%. Work values increased with an in
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Ling, Yuanfei, Xiaoqiang Wang, and Jiren Tang. "Dynamic Simulation Model and Performance Optimization of a Pressurized Pulsed Water Jet Device." Applied Sciences 14, no. 15 (2024): 6788. http://dx.doi.org/10.3390/app14156788.

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Pulsed water jet technology has broad application prospects in the field of rock breaking. The pressurized pulsed water jet (PPWJ) is a new type of pulsed jet that offers high-amplitude pressurization, variable pulse pressure and frequency, and a high energy usage rate. To achieve a more destructive and powerful pulsed water jet, a dynamic simulation model of the device was established by using the AMESim software (v1400) based on the operational principle of PPWJs, and the simulation model was validated against the experimental results. The relationships between the key structural parameters
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Chuvaev, I. V., Zh S. Вudnik, and A. V. Yashin. "Characteristics of electromagnetic radiation of the veterinary physiotherapy device UMI-05-V." International Journal of Veterinary Medicine, no. 2 (June 28, 2024): 393–99. http://dx.doi.org/10.52419/issn2072-2419.2024.2.393.

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We studied some physical characteristics of the veterinary physiotherapeutic device UMI-V-05. The magnetic induction at different power levels was determined using TPU 02 militeslameter. The magnetic induction was measured for each power value. The probe of the milliteslameter was placed directly on the working surface, in the center of the inductor. It was found that the minimum magnetic induction of the device is 350±6.0 mTl, and the maximum is 1058±10.0 mTl. During the device operation, the heating of the inductor was determined using a thermal imager and a stopwatch. During the recommended
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Zhou, Guangqi, Ye Tian, Feng Shi, et al. "Low-Energy Pulsed Ion Beam Technology with Ultra-High Material Removal Resolution and Widely Adjustable Removal Efficiency." Micromachines 12, no. 11 (2021): 1370. http://dx.doi.org/10.3390/mi12111370.

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High-precision optical component manufacturing by ion beam machining tools with ultra-high material removal resolution and dynamically adjustable removal efficiency is important in various industries. In this paper, we propose a low-energy pulsed ion beam (LPIB) technology that can obtain a single pulse with high-resolution material removal by adjusting the pulse frequency and duty cycle, and enable the dynamic adjustment of the removal efficiency. The pulse frequency is 1–100 Hz, and the duty cycle is 0–100%. For monocrystalline silicon, the pulse frequency and duty cycle are set to 100 Hz an
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Wang, Yong, Hongjian Ni, Ruihe Wang, et al. "Effect of Pulsed Jet on Pore Pressure of Deep Formation Rock." Shock and Vibration 2021 (December 29, 2021): 1–9. http://dx.doi.org/10.1155/2021/2217787.

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Pulsed jet significantly affects the pore pressure of deep formation and then affects the mechanical ROP. In this paper, the effect of jet pulsation on deep pore pressure in the formation is studied by the finite element method. Under the pulsed jet, the maximum relative negative pressure is along the wellbore axis, and the farther it is to the borehole axis, the smaller the relative negative pressure is. With the increase of pulse frequency, the relative negative pressure increases and the maximum point of relative negative pressure moves upward. The optimum pulse frequency is from 50 Hz to 5
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Zhang, Jiale, Jian Ma, Tingting Lu, and Xiaolei Zhu. "486 nm pulsed Nd:YLF laser with intracavity sum-frequency mixing." Laser Physics Letters 20, no. 5 (2023): 055001. http://dx.doi.org/10.1088/1612-202x/accf77.

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Abstract An intracavity sum-frequency pulsed laser emitting at 486 nm was demonstrated in a combined cavity for two electro-optically Q-switched Nd:YLF fundamental lasers emitting at 908 nm and 1047 nm respectively. Pumped by two 806 nm LDs at 50 Hz repetition rate, while the intracavity pulse energy reached 6.25 mJ at 908 nm and 2.57 mJ at 1047 nm, maximum output pulse energy of 0.26 mJ at 486.4 nm wavelength was successfully achieved by intracavity sum-frequency. The corresponding spectral bandwidth was less than 0.08 nm, and the pulse width was about 11.8 ns. The peak power of the blue lase
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Danilov, V. N. "ON THE INFLUENCE OF THE PARAMETERS OF THE ELECTRIC EXCITATION PULSE OF A PIEZOELECTRIC PLATE OF A NORMAL PROBE ON THE CHARACTERISTICS OF THE FREQUENCY SPECTRUM AND PULSE OF THE RECORDED ECHO SIGNAL." Kontrol'. Diagnostika, no. 291 (September 2022): 14–22. http://dx.doi.org/10.14489/td.2022.09.pp.014-022.

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On the basis of computer modeling of the electro acoustic channel of a normal probe for a reflector in the form of a bottom surface, the influence of some typical forms and corresponding frequency spectra of the electric pulse of excitation of the piezoelectric plate on the characteristics of the frequency spectrum and pulse of the recorded echo signal is considered. Calculations of signals using an exciting pulse in the form of a voltage jump (step), in the form of half a sine wave and a rectangular shape have shown the feasibility of using rectangular pulses with a duration equal to half of
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Moriizumi, Takenori. "Ultrasonic imaging system capable of varying maximum pulse repetition frequency depending upon pulse transmission frequency." Journal of the Acoustical Society of America 97, no. 2 (1995): 1369. http://dx.doi.org/10.1121/1.412115.

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Zhan, Haihong, Tao Wang, Tai Guo, and Xingde Su. "An Anti-Intermittent Sampling Jamming Technique Utilizing the OTSU Algorithm of Random Orthogonal Sub-Pulses." Remote Sensing 15, no. 12 (2023): 3080. http://dx.doi.org/10.3390/rs15123080.

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The utilization of intermittent sampling jamming can engender a lofty verisimilitude false target cluster that exhibits coherence with the transmitted signal. Such an assemblage bears the hallmarks of both suppression jamming and deceitful jamming, capable of inflicting substantial impairment upon the radar, potentially leading to its profound incapacitation. Henceforth, the precise discernment of the target and various forms of intermittent sampling jamming emerges as a novel endeavor. In response to this predicament, this paper posits a pulsed radar waveform featuring intra-pulse random orth
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Dissertations / Theses on the topic "Maximum pulse frequency"

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Федик, Степан Романович, та Stepan Fedyk. "Імпульсне живлення світлодіодних систем освітлення". Master's thesis, Тернопільський національний технічний університет імені Івана Пулюя, кафедра електричної інженерії,Тернопіль, Україна, 2021. http://elartu.tntu.edu.ua/handle/lib/36655.

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Світлодіодні джерела світла, завойовують все більшу популярність на ринку, завдяки своїм економічним та експлуатаційним характеристикам. В ході досліджень [18] було виявлено що оптимальний термін служби світлодіодних джерел освітлення сягає 25 000 год., що в рази більше мінімально визначеного законодавством ЄС – 6 000 год. Згідно даних міжнародного стандарту енергоефективності споживчих товарів «Energy Star» [15], світлодіодна лампа потужністю 9W обходиться покупцеві в 1,26 дол/рік, тоді як галогенна лампа потужністю 43 Вт з аналогічним світловим потоком обходиться в 6,02 дол/рік. Згідно стати
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Simeonov, Gregor. "Resonant Boost Converter for Distributed Maximum Power Point Tracking in Grid-connected Photovoltaic Systems." Thesis, 2012. http://hdl.handle.net/1807/33704.

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This thesis introduces a new photovoltaic (PV) system architecture employing low voltage parallel-connected PV panels interfaced to a high voltage regulated DC bus of a three-phase grid-tied inverter. The concept provides several improvements over existing technologies in terms of cost, safety, reliability, and modularity. A novel resonant mode DC-DC boost converter topology is proposed to enable the PV modules to deliver power to the fixed DC bus. The topology offers high step-up capabilities and a nearly constant efficiency over a wide operating range. A reduced sensor maximum power point tr
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Book chapters on the topic "Maximum pulse frequency"

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Yang, Lixiang, Yaobin Han, Xu Zhang, and Zhiwen Li. "Numerical Simulation for the Dynamic Response of Step Topography Subjected to Blasting Load." In Lecture Notes in Civil Engineering. Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-2532-2_15.

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AbstractThe vibration velocity and frequency of rock mass are closely related to the instability and failure of the building. The step topography has great influence on blasting vibration wave propagation. Therefore, it is of great significance to study the dynamic response of step topography subjected to blasting load. In this paper, the FLAC2D program is used to study the dynamic response of step topography subjected to blasting load. The plane strain mode is adopted in the calculation, and the blasting load is assumed to be a triangular pulse wave which is applied to one side of the calcula
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Nundy, Utpal, Ramesh Chandra Das, and Ayan Ghosh. "Rotating Mirror Q-Switched CO Laser: Optimization of Power Spectrum on Mirror Rotation – A Theoretical Study." In Pulsed Laser Technologies - Advanced Techniques and Cutting-Edge Applications [Working Title]. IntechOpen, 2025. https://doi.org/10.5772/intechopen.1011574.

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This theoretical study explores the performance of a cryogenically cooled Q-switched CO laser utilizing a Rotating Mirror Q-Switching technique. By varying the mirror rotation frequency from 50 to 625 Hz, we optimized the output power and spectral characteristics, achieving a peak power of 200 kW at 500 Hz with a pulse FWHM of 220 ns. The Q-switched pulse comprises approximately 100 CO laser lines spanning 5.0–6.2 μm, with 65 lines exceeding 100 W and a maximum of 25 kW. These characteristics make the laser highly suitable for nonlinear sum-frequency generation in crystals. This work provides
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Smiley, Aref, Te-Yi Tsai, Elena Zakashansky, et al. "Exercise Exertion Levels Prediction Based on Real-Time Wearable Physiological Signal Monitoring." In Studies in Health Technology and Informatics. IOS Press, 2023. http://dx.doi.org/10.3233/shti230454.

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The real-time revolutions per minute (RPM) data, ECG signal, pulse rate, and oxygen saturation levels were collected during 16-minute cycling exercises. In parallel, ratings of perceived exertion (RPE) were collected each minute from the study participants. A 2-minute moving window, with one minute shift, was applied to each 16-minute exercise session to divide it into a total of fifteen 2-minute windows. Based on the self-reported RPE, each exercise window was labeled as “high exertion” or “low exertion” classes. The heart rate variability (HRV) characteristics in time and frequency domains w
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Saravanan, D., and KR Velunachiyar. "A STUDY ON THE BIOCHEMICAL & MORPHOLOGICAL CHANGES ON GROUNDNUT (ARACHIS HYPOGAEA) SEEDS EXPOSED TO PULSED MAGNETIC FIELD." In Futuristic Trends in Biotechnology Volume 3 Book 15. Iterative International Publishers, Selfypage Developers Pvt Ltd, 2024. http://dx.doi.org/10.58532/v3bjbt15p6ch2.

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Arachis hypogeae seeds were exposed to a pulsed magnetic field of sine wave form with varying frequencies as 100, 500, 1000 Hz and constant intensity of about 1500 nT. The seeds were exposed to frequency of 100 Hz is taken as Test-1, 500 Hz as Test – 2, 1000 Hz as Test10– 3. Seeds are subjected to the high pulsed magnetic field for a time interval of 5 hours per day for 15 days. After the exposure time over, on the 16 th day, the estimations are carried out for carbohydrates, proteins, amino acids, nucleic acids (DNA & RNA), enzymes (Amylase &Protease).It is seen from the experiment th
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Redfield, A. G. "On the possibility of nuclear self-spin-locking in ferromagnets." In Pulsed Magnetic Resonance: NMR, ESR, and Optics. Oxford University PressOxford, 1992. http://dx.doi.org/10.1093/oso/9780198539629.003.0008.

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Abstract Nuclear spin systems in ferromagnets and antiferromagnets can bend the electronic magnetization, via their hyperfine interaction, so as to produce an apparent magnetic field that is proportional to the transverse nuclear spin magnetization and parallel to it. A nuclear spin system in any solid can also be ‘spin-locked’ by application of a resonant r.f. field along a transverse nuclear magnetization, and transverse spin relaxation is then prevented by the r.f. field. In this Article we combine these ideas and conclude that nuclear spin systems in (anti)ferromagnets might be placed in a
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"Conservation, Ecology, and Management of Catfish: The Second International Symposium." In Conservation, Ecology, and Management of Catfish: The Second International Symposium, edited by ROBERT S. GREENLEE and CATHERINE N. LIM. American Fisheries Society, 2011. http://dx.doi.org/10.47886/9781934874257.ch30.

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<em>Abstract</em>.—Introduced blue catfish <em>Ictalurus furcatus</em> populations in tidal rivers of the Atlantic slope support important recreational and commercial fisheries, with the James River trophy fishery being nationally recognized. During the period 2001–2008, low-frequency (15 pulses/s) pulsed DC electrofishing was used to sample blue catfish in tidal fresh-oligohaline sections of the James, Mattaponi, Pamunkey, and Rappahannock River systems; 54,174 blue catfish were collected, and 4,660 of these were aged using otoliths. Mean catch per unit effort (CPUE) w
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Conference papers on the topic "Maximum pulse frequency"

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Yan, Wenzhuo, Andrew Tieu, Baolin Ren, and Mohan Vijay. "High-Frequency Forced Pulsed Waterjet Technology for the Removal of Coatings." In SSPC 2002. SSPC, 2002. https://doi.org/10.5006/s2002-00028.

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Abstract High-frequency forced pulsed waterjet technology is an advanced technique that has great potential for many industrial applications. Over the past 10 years, extensive research and development work has been conducted to evaluate this technology specifically for the removal of several types of industrial coatings. More recently, forced-pulsed waterjet machines have been tested in the field to compare their performance, reliability and advantages against the existing ubiquitous ultrahigh pressure continuous waterjet machines. In this paper three such machines are briefly described, with
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Nishizawa, N., Y. Ozawa, S. Kitajima та ін. "Power Scaling of Optical Frequency Comb Sources at λ = 1.4 µm Using Fiber Raman Amplifier". У Advanced Solid State Lasers. Optica Publishing Group, 2024. https://doi.org/10.1364/assl.2024.jw2a.38.

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Soyama, Hitoshi. "Laser Cavitation Peening Using a Nd:YAG Laser and a Fiber Laser." In Laser Applications Conference. Optica Publishing Group, 2024. https://doi.org/10.1364/lac.2024.lth2b.4.

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Cavitation is a harmful phenomenon for hydraulic machineries such as pumps and valves etc., as it causes severe erosion by impacts at cavitation bubble collapses. However, the cavitation impacts can be utilized for mechanical surface modification in the same way of shot peening. A peening method using cavitation impact is called as “cavitation peening”, especially cavitation peening using a pulsed laser is named as “laser cavitation peening”. Laser cavitation peening can improve fatigue strength of additively manufactured (AM) metals. However, it takes time to treat, as the repletion frequency
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Hardesty, R. M., R. E. Cupp, and T. R. Lawrence. "Development and Application of an Injection Locked, Pulsed CO2 Doppler Lidar for Atmospheric Remote Sensing." In Coherent Laser Radar. Optica Publishing Group, 1987. http://dx.doi.org/10.1364/clr.1987.thb3.

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During the summer of 1985, the Wave Propagation Laboratory of NOAA upgraded its pulsed CO2 Doppler lidar with a new transceiver. Previously, the system had operated with a hybrid TEA transmitter, producing approximately 100 mJ of energy per pulse at a 10 Hz pulse repetition frequency (prf). The upgraded transceiver, built by Spectra Technologies, Incorporated, of Bellevue, Washington, uses an injection-locked, unstable resonator configuration to produce frequency-stable pulses with 2 J of energy per pulse; maximum prf of the injection-locked system is 50 Hz. The larger pulse energy and higher
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McKay, Ian Salmon, and Evelyn N. Wang. "Pulsed Heat Transfer for Thermal Maximum Power Point Tracking." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-62998.

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This paper presents a new method for enhancing thermal energy harvesting via pulsed heat transfer. By acting as a variable thermal resistance that theoretically generates no entropy, a pulsed thermal connection allows calibration of the effective thermal resistance of an energy harvesting system. By adjusting the frequency and duty cycle of the pulsed heat transfer, the method allows an energy harvester to be continuously optimized for a variable incident heat flux. In this paper, the analysis of a generalized model shows how the pulse strategy theoretically allows any heat engine-heat sink pa
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Foing, J. P., J. P. Likforman, and M. Joffre. "Femtosecond Pulse Phase Measurement by Spectrally Resolved UP-Conversion." In International Conference on Ultrafast Phenomena. Optica Publishing Group, 1992. http://dx.doi.org/10.1364/up.1992.mc10.

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We report the direct determination of the phase of femtosecond light pulses by spectrally resolved up-conversion. The correlation signal spectrum is recorded for different delays between the probed pulse to characterize and a reference one. The phase derivative of the probed pulse is then retrieved considering for each UV wavelength the delay for which its intensity is maximum (fig. 1). Basically this technique is a frequency sampling of the probed pulse and therefore needs a spectrally narrow reference beam. This is clearly seen in the case of linearly chirped gaussian pulses where solutions
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Ben-David, Avishai, Silvio L. Emery, Steven W. Gotoff, and Francis D’Amico. "A New High Pulse Repetition Frequency, Multiple Wavelength, Differential Absorption CO2 Lidar System for Atmospheric Trace Gas Measurements." In Optical Remote Sensing of the Atmosphere. Optica Publishing Group, 1991. http://dx.doi.org/10.1364/orsa.1991.otub2.

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A multiple wavelength, pulsed CO2 lidar system that operates at a pulse repetition frequency (PRF) up to 200 Hz (for a single wavelength) and permits the random selection of CO2 laser wavelengths for each laser pulse is presented. The CO2 laser was developed by Laser Science Incorporated, Cambridge, Massachusetts. The lidar system is employed to measure atmospheric transmission using laser pulse bursts consisting of groups of 10 different wavelengths (the maximum available is 16 wavelengths) at a repetition rate of up to 3 Hz (the maximum available is 12 Hz) and at a PRF of 150 Hz for waveleng
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Nomura, Hideyuki, and Riku Nishioka. "Low-frequency parametric ultrasound imaging using pulse compression with maximum-length sequence excitation." In 21st International Symposium on Nonlinear Acoustics. Acoustical Society of America, 2018. http://dx.doi.org/10.1121/2.0000840.

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Potasek, M. J., and Govind P. Agrawal. "Modulation instability leading to self-amplitude modulation of optical pulses in nonlinear dispersive fibers." In OSA Annual Meeting. Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.mcc1.

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Propagation of a cw optical beam in fibers1 is inherently unstable in the anomalous dispersion regime, a phenomenon referred to as modulation instability (MI). Its observation2 has required a noise input or an independent beam at the maximum-gain frequency. In this paper we show that self-phase modulation of optical pulses can broaden the spectrum enough to encompass the maximum gain frequency and to induce self-amplitude modulation through MI. We solve the nonlinear Schrodinger equation numerically and find that in appropriate conditions a 100-ps pulse breaks into a sequence of pulses whose p
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White, IH, and AM Lomax. "Picosecond pulse gating by high frequency modulation of semiconductor laser amplifiers." In Optical Amplifiers and Their Applications. Optica Publishing Group, 1990. http://dx.doi.org/10.1364/oaa.1990.wc2.

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There has recently been much interest in using optical devices for modulation of optical signals to achieve drop/insert functions in high bit rate time division multiplexed communication systems. Optical semiconductor amplifiers are suited for such applications, in providing optical gain along with switching, in providing high off/on contrast ratios and in operating over a wavelength range directly compatible with diode lasers. This paper reports experimental and theoretical results of high speed electrical modulation of semiconductor laser amplifiers carried out with the aim of determining th
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