WorldWideScience

Sample records for ultrasonic output power

  1. Study of Contactless Power Supply for Spindle Ultrasonic Vibrator

    Science.gov (United States)

    Chen, T. R.; Lee, Y. L.; Liu, H. T.; Chen, S. M.; Chang, H. Z.

    2017-11-01

    In this study, a contactless power supply for the ultrasonic motor on the spindle is proposed. The proposed power supply is composed of a series-parallel resonant circuit and a cylindrical contactless transformer. Based on the study and rotation experiments, it can be seen that the proposed power supply can both provide a stable ac power with 25 kHz / 70 V to the ultrasonic motor. When the output power is 250 W, the efficiency of the proposed supply is 89.8 % in respectively rotation tests. When the output power is more than 150 W, the efficiency of the proposed supply is higher than 80 % within the rated output power range.

  2. Measurement of total ultrasonic power using thermal expansion and change in buoyancy of an absorbing target.

    Science.gov (United States)

    Dubey, P K; Kumar, Yudhisther; Gupta, Reeta; Jain, Anshul; Gohiya, Chandrashekhar

    2014-05-01

    The Radiation Force Balance (RFB) technique is well established and most widely used for the measurement of total ultrasonic power radiated by ultrasonic transducer. The technique is used as a primary standard for calibration of ultrasonic transducers with relatively fair uncertainty in the low power (below 1 W) regime. In this technique, uncertainty comparatively increases in the range of few watts wherein the effects such as thermal heating of the target, cavitations, and acoustic streaming dominate. In addition, error in the measurement of ultrasonic power is also caused due to movement of absorber at relatively high radiated force which occurs at high power level. In this article a new technique is proposed which does not measure the balance output during transducer energized state as done in RFB. It utilizes the change in buoyancy of the absorbing target due to local thermal heating. The linear thermal expansion of the target changes the apparent mass in water due to buoyancy change. This forms the basis for the measurement of ultrasonic power particularly in watts range. The proposed method comparatively reduces uncertainty caused by various ultrasonic effects that occur at high power such as overshoot due to momentum of target at higher radiated force. The functionality of the technique has been tested and compared with the existing internationally recommended RFB technique.

  3. Measurement of total ultrasonic power using thermal expansion and change in buoyancy of an absorbing target

    Science.gov (United States)

    Dubey, P. K.; Kumar, Yudhisther; Gupta, Reeta; Jain, Anshul; Gohiya, Chandrashekhar

    2014-05-01

    The Radiation Force Balance (RFB) technique is well established and most widely used for the measurement of total ultrasonic power radiated by ultrasonic transducer. The technique is used as a primary standard for calibration of ultrasonic transducers with relatively fair uncertainty in the low power (below 1 W) regime. In this technique, uncertainty comparatively increases in the range of few watts wherein the effects such as thermal heating of the target, cavitations, and acoustic streaming dominate. In addition, error in the measurement of ultrasonic power is also caused due to movement of absorber at relatively high radiated force which occurs at high power level. In this article a new technique is proposed which does not measure the balance output during transducer energized state as done in RFB. It utilizes the change in buoyancy of the absorbing target due to local thermal heating. The linear thermal expansion of the target changes the apparent mass in water due to buoyancy change. This forms the basis for the measurement of ultrasonic power particularly in watts range. The proposed method comparatively reduces uncertainty caused by various ultrasonic effects that occur at high power such as overshoot due to momentum of target at higher radiated force. The functionality of the technique has been tested and compared with the existing internationally recommended RFB technique.

  4. Measurement of total ultrasonic power using thermal expansion and change in buoyancy of an absorbing target

    International Nuclear Information System (INIS)

    Dubey, P. K.; Kumar, Yudhisther; Gupta, Reeta; Jain, Anshul; Gohiya, Chandrashekhar

    2014-01-01

    The Radiation Force Balance (RFB) technique is well established and most widely used for the measurement of total ultrasonic power radiated by ultrasonic transducer. The technique is used as a primary standard for calibration of ultrasonic transducers with relatively fair uncertainty in the low power (below 1 W) regime. In this technique, uncertainty comparatively increases in the range of few watts wherein the effects such as thermal heating of the target, cavitations, and acoustic streaming dominate. In addition, error in the measurement of ultrasonic power is also caused due to movement of absorber at relatively high radiated force which occurs at high power level. In this article a new technique is proposed which does not measure the balance output during transducer energized state as done in RFB. It utilizes the change in buoyancy of the absorbing target due to local thermal heating. The linear thermal expansion of the target changes the apparent mass in water due to buoyancy change. This forms the basis for the measurement of ultrasonic power particularly in watts range. The proposed method comparatively reduces uncertainty caused by various ultrasonic effects that occur at high power such as overshoot due to momentum of target at higher radiated force. The functionality of the technique has been tested and compared with the existing internationally recommended RFB technique

  5. Design and characterization of a high-power ultrasound driver with ultralow-output impedance

    Science.gov (United States)

    Lewis, George K.; Olbricht, William L.

    2009-11-01

    We describe a pocket-sized ultrasound driver with an ultralow-output impedance amplifier circuit (less than 0.05 Ω) that can transfer more than 99% of the voltage from a power supply to the ultrasound transducer with minimal reflections. The device produces high-power acoustical energy waves while operating at lower voltages than conventional ultrasound driving systems because energy losses owing to mismatched impedance are minimized. The peak performance of the driver is measured experimentally with a PZT-4, 1.54 MHz, piezoelectric ceramic, and modeled using an adjusted Mason model over a range of transducer resonant frequencies. The ultrasound driver can deliver a 100 Vpp (peak to peak) square-wave signal across 0-8 MHz ultrasound transducers in 5 ms bursts through continuous wave operation, producing acoustic powers exceeding 130 W. Effects of frequency, output impedance of the driver, and input impedance of the transducer on the maximum acoustic output power of piezoelectric transducers are examined. The small size, high power, and efficiency of the ultrasound driver make this technology useful for research, medical, and industrial ultrasonic applications.

  6. Development of a multi-path ultrasonic flow meter for the application to feedwater flow measurement in nuclear power plants

    International Nuclear Information System (INIS)

    Jong, J. C.; Ha, J. H.; Kim, Y. H.; Jang, W. H.; Park, K. S.; Park, M. S.; Park, M. H.

    2002-01-01

    In this work, we propose a method to measure the feedwater flow using multi-path ultrasonic flow meter (UFM). Since the UFM measures a path velocity at which the ultrasonic wave is propagated, the flow profile may be important to convey the path velocity to the velocity averaged over the entire cross section of the flowing medium. The conventional UFM has used the smooth-wall circular pipe model presented by Nikurades. However, this model covers a lower range which is less than 3.2 million while the Reynolds number of the feedwater flow in operating nuclear power plants (NPPs) is about 20 million. Therefore, we feedwater flow in operating nuclear power plants (NPPs) is about 20 million. Therefore, we proposed the non-linear correlation model that combines the ratio between the DP output and proposed the non-linear correlation model that combines the ratio between the DP output and UFM output. Experiments were performed using both computer simulation and newly constructed NPPs' test data. The uncertainty analysis result shows that the proposed method has reasonably lower uncertainty than conventional UFM

  7. Effect of Heat Generation of Ultrasound Transducer on Ultrasonic Power Measured by Calorimetric Method

    Science.gov (United States)

    Uchida, Takeyoshi; Kikuchi, Tsuneo

    2013-07-01

    Ultrasonic power is one of the key quantities closely related to the safety of medical ultrasonic equipment. An ultrasonic power standard is required for establishment of safety. Generally, an ultrasonic power standard below approximately 20 W is established by the radiation force balance (RFB) method as the most accurate measurement method. However, RFB is not suitable for high ultrasonic power because of thermal damage to the absorbing target. Consequently, an alternative method to RFB is required. We have been developing a measurement technique for high ultrasonic power by the calorimetric method. In this study, we examined the effect of heat generation of an ultrasound transducer on ultrasonic power measured by the calorimetric method. As a result, an excessively high ultrasonic power was measured owing to the effect of heat generation from internal loss in the transducer. A reference ultrasound transducer with low heat generation is required for a high ultrasonic power standard established by the calorimetric method.

  8. Wireless power transmission using ultrasonic guided waves

    International Nuclear Information System (INIS)

    Kural, A; Pullin, R; Featherston, C; Holford, K; Paget, C

    2011-01-01

    The unavailability of suitable power supply at desired locations is currently an important obstacle in the development of distributed, wireless sensor networks for applications such as structural health monitoring of aircraft. Proposed solutions range from improved batteries to energy harvesting from vibration, temperature gradients and other sources. A novel approach is being investigated at Cardiff University School of Engineering in cooperation with Airbus. It aims to utilise ultrasonic guided Lamb waves to transmit energy through the aircraft skin. A vibration generator is to be placed in a location where electricity supply is readily available. Ultrasonic waves generated by this device will travel through the aircraft structure to a receiver in a remote wireless sensor node. The receiver will convert the mechanical vibration of the ultrasonic waves back to electricity, which will be used to power the sensor node. This paper describes the measurement and modelling of the interference pattern which emerges when Lamb waves are transmitted continuously as in this power transmission application. The discovered features of the pattern, such as a large signal amplitude variation and a relatively high frequency, are presented and their importance for the development of a power transmission system is discussed.

  9. Wireless power transmission using ultrasonic guided waves

    Energy Technology Data Exchange (ETDEWEB)

    Kural, A; Pullin, R; Featherston, C; Holford, K [School of Engineering, Cardiff University, Queens Buildings, The Parade, Cardiff CF24 2AA (United Kingdom); Paget, C, E-mail: kurala@cardiff.ac.uk [Airbus Operations Ltd, New Filton Road, BS99 7AR Bristol (United Kingdom)

    2011-07-19

    The unavailability of suitable power supply at desired locations is currently an important obstacle in the development of distributed, wireless sensor networks for applications such as structural health monitoring of aircraft. Proposed solutions range from improved batteries to energy harvesting from vibration, temperature gradients and other sources. A novel approach is being investigated at Cardiff University School of Engineering in cooperation with Airbus. It aims to utilise ultrasonic guided Lamb waves to transmit energy through the aircraft skin. A vibration generator is to be placed in a location where electricity supply is readily available. Ultrasonic waves generated by this device will travel through the aircraft structure to a receiver in a remote wireless sensor node. The receiver will convert the mechanical vibration of the ultrasonic waves back to electricity, which will be used to power the sensor node. This paper describes the measurement and modelling of the interference pattern which emerges when Lamb waves are transmitted continuously as in this power transmission application. The discovered features of the pattern, such as a large signal amplitude variation and a relatively high frequency, are presented and their importance for the development of a power transmission system is discussed.

  10. High-power ultrasonic processing: Recent developments and prospective advances

    Science.gov (United States)

    Gallego-Juarez, Juan A.

    2010-01-01

    Although the application of ultrasonic energy to produce or to enhance a wide variety of processes have been explored since about the middle of the 20th century, only a reduced number of ultrasonic processes have been established at industrial level. However, during the last ten years the interest in ultrasonic processing has revived particularly in industrial sectors where the ultrasonic technology may represent a clean and efficient tool to improve classical existing processes or an innovation alternative for the development of new processes. Such seems to be the case of relevant sectors such as food industry, environment, pharmaceuticals and chemicals manufacture, machinery, mining, etc where power ultrasound is becoming an emerging technology for process development. The possible major problem in the application of high-intensity ultrasound on industrial processing is the design and development of efficient power ultrasonic systems (generators and reactors) capable of large scale successful operation specifically adapted to each individual process. In the area of ultrasonic processing in fluid media and more specifically in gases, the development of the steppedplate transducers and other power ge with extensive radiating surface has strongly contributed to the implementation at semi-industrial and industrial stage of several commercial applications, in sectors such as food and beverage industry (defoaming, drying, extraction, etc), environment (air cleaning, sludge filtration, etc...), machinery and process for manufacturing (textile washing, paint manufacture, etc). The development of different cavitational reactors for liquid treatment in continuous flow is helping to introduce into industry the wide potential of the area of sonochemistry. Processes such as water and effluent treatment, crystallization, soil remediation, etc have been already implemented at semi-industrial and/or industrial stage. Other single advances in sectors like mining or energy have

  11. Industrial Applications of High Power Ultrasonics

    Science.gov (United States)

    Patist, Alex; Bates, Darren

    Since the change of the millennium, high-power ultrasound has become an alternative food processing technology applicable to large-scale commercial applications such as emulsification, homogenization, extraction, crystallization, dewatering, low-temperature pasteurization, degassing, defoaming, activation and inactivation of enzymes, particle size reduction, extrusion, and viscosity alteration. This new focus can be attributed to significant improvements in equipment design and efficiency during the late 1990 s. Like most innovative food processing technologies, high-power ultrasonics is not an off-the-shelf technology, and thus requires careful development and scale-up for each and every application. The objective of this chapter is to present examples of ultrasonic applications that have been successful at the commercialization stage, advantages, and limitations, as well as key learnings from scaling up an innovative food technology in general.

  12. Systematic evaluation of a secondary method for measuring diagnostic-level medical ultrasound transducer output power based on a large-area pyroelectric sensor

    Science.gov (United States)

    Zeqiri, B.; Žauhar, G.; Rajagopal, S.; Pounder, A.

    2012-06-01

    A systematic study of the application of a novel pyroelectric technique to the measurement of diagnostic-level medical ultrasound output power is described. The method exploits the pyroelectric properties of a 0.028 mm thick membrane of polyvinylidene fluoride (PVDF), backed by an acoustic absorber whose ultrasonic absorption coefficient approaches 1000 dB cm-1 at 3 MHz. When exposed to an ultrasonic field, absorption of ultrasound adjacent to the PVDF-absorber interface results in heating and the generation of a pyroelectric output voltage across gold electrodes deposited on the membrane. For a sensor large enough to intercept the whole of the acoustic beam, the output voltage can be calibrated for the measurement of acoustic output power. A number of key performance properties of the method have been investigated. The technique is very sensitive, with a power to voltage conversion factor of typically 0.23 V W-1. The frequency response of a particular embodiment of the sensor in which acoustic power reflected at the absorber-PVDF interface is subsequently returned to the pyroelectric membrane to be absorbed, has been evaluated over the frequency range 1.5 MHz to 10 MHz. This has shown the frequency response to be flat to within ±4%, above 2.5 MHz. Below this frequency, the sensitivity falls by 20% at 1.5 MHz. Linearity of the technique has been demonstrated to within ±1.6% for applied acoustic power levels from 1 mW up to 120 mW. A number of other studies targeted at assessing the achievable measurement uncertainties are presented. These involve: the effects of soaking, the influence of the angle of incidence of the acoustic beam, measurement repeatability and sensitivity to transducer positioning. Additionally, over the range 20 °C to 30 °C, the rate of change in sensitivity with ambient temperature has been shown to be +0.5% °C-1. Implications of the work for the development of a sensitive, traceable, portable, secondary method of ultrasound output power

  13. Measurement of hydroxyl radical production in ultrasonic aqueous solutions by a novel chemiluminescence method.

    Science.gov (United States)

    Hu, Yufei; Zhang, Zhujun; Yang, Chunyan

    2008-07-01

    Measurement methods for ultrasonic fields are important for reasons of safety. The investigation of an ultrasonic field can be performed by detecting the yield of hydroxyl radicals resulting from ultrasonic cavitations. In this paper, a novel method is introduced for detecting hydroxyl radicals by a chemiluminescence (CL) reaction of luminol-hydrogen peroxide (H2O2)-K5[Cu(HIO6)2](DPC). The yield of hydroxyl radicals is calculated directly by the relative CL intensity according to the corresponding concentration of H2O2. This proposed CL method makes it possible to perform an in-line and real-time assay of hydroxyl radicals in an ultrasonic aqueous solution. With flow injection (FI) technology, this novel CL reaction is sensitive enough to detect ultra trace amounts of H2O2 with a limit of detection (3sigma) of 4.1 x 10(-11) mol L(-1). The influences of ultrasonic output power and ultrasonic treatment time on the yield of hydroxyl radicals by an ultrasound generator were also studied. The results indicate that the amount of hydroxyl radicals increases with the increase of ultrasonic output power (< or = 15 W mL(-1)). There is a linear relationship between the time of ultrasonic treatment and the yield of H2O2. The ultrasonic field of an ultrasonic cleaning baths has been measured by calculating the yield of hydroxyl radicals.

  14. An ultrasonic waveguide for nuclear power plants

    International Nuclear Information System (INIS)

    Watkins, R.D.; Gillespie, A.B.; Deighton, M.O.; Pike, R.B.

    1983-01-01

    The value of ultrasonic techniques in nuclear plants is well established. However, in most cases nuclear power plants present an extremely hostile environment for an ultrasonic transducer. The paper presents a novel technique for introducing an ultrasound into hostile liquid environments using a new form of ultrasonic waveguide. Using this approach, a standard transducer arrangement is sited in a hospitable area and conveys the ultrasound along the guide to the required beam-emission collection position. The design of a single-mode ultrasonic waveguide is described. The ultrasound is conveyed along a stainless steel strip of rectangular cross-section. The transference of energy between the strip and the liquid is achieved through a highly efficient mode-conversion process. This process overcomes the usual problems of mis-match of acoustic impedances of stainless steel and liquids, and also produces a highly collimated beam of ultrasound. Tests of a 10-m-long waveguide using these techniques are described, achieving signal-to-noise ratios in the region of 40 dB. (author)

  15. Impact of applied ultrasonic power on the low temperature drying of apple.

    Science.gov (United States)

    Santacatalina, J V; Contreras, M; Simal, S; Cárcel, J A; Garcia-Perez, J V

    2016-01-01

    Low temperature drying (LTD) allows high-quality dried products to be obtained, preserving the nutritional properties of fresh foods better than conventional drying, but it is a time-consuming operation. Power ultrasound (US) could be used to intensify LTD, but it should be taken into account that process variables, such as the level of applied power, have an influence on the magnitude and extension of the ultrasonic effects. Therefore, the aim of this work was to assess the influence of the level of applied ultrasonic power on the LTD of apple, analyzing the drying kinetics and the quality of the dried product. For that purpose, apple (Malus domestica cv. Granny Smith) cubes (8.8mm side) were dried (2m/s) at two different temperatures (10 and -10°C), without and with (25, 50 and 75 W) US application. In the dried apple, the rehydration kinetics, hardness, total phenolic content, antioxidant capacity and microstructure were analyzed to evaluate the impact of the level of applied ultrasonic power. At both temperatures, 10 and -10°C, the higher the ultrasonic power level, the shorter the drying time; the maximum shortening of the drying time achieved was 80.3% (at -10°C and 75 W). The ultrasonic power level did not significantly (pfruits, like apple, with only a mild impact on the quality of the dried product. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Ultrasonic filtration of industrial chemical solutions

    Science.gov (United States)

    Cosma, T.

    1974-01-01

    The practical results obtained as a result of filtering industrial chemical solutions under continuous flow conditions with the aid of an ultrasonic filter are presented. The main part of the assembly consists of an ultrasonic generator with an output power of about 400 W and the filtration assembly, in which there is a magnetostrictive amplifier constructed for 20.5 kHz. In addition to ensuring a continuous flow of filtered solution, ultrasonic filters can be replaced or cleaned at intervals of time that are 8-10 times greater than in the case of mechanical filters. They yield considerably better results as far as the size of the filtered particles is concerned. The parameters on which filtration quality depends are also presented.

  17. Analysis of Defective Pipings in Nuclear Power Plants and Applications of Guided Ultrasonic Wave Techniques

    International Nuclear Information System (INIS)

    Koo, Dae Seo; Cheong, Yong Moo; Jung, Hyun Kyu; Park, Chi Seung; Park, Jae Suck; Choi, H. R.; Jung, S. S.

    2006-07-01

    In order to apply the guided ultrasonic techniques to the pipes in nuclear power plants, the cases of defective pipes of nuclear power plants, were investigated. It was confirmed that geometric factors of pipes, such as location, shape, and allowable space were impertinent for the application of guided ultrasonic techniques to pipes of nuclear power plants. The quality of pipes, supports, signals analysis of weldment/defects, acquisition of accurate defects signals also make difficult to apply the guided ultrasonic techniques to pipes of nuclear power plants. Thus, a piping mock-up representing the pipes in the nuclear power plants were designed and fabricated. The artificial flaws will be fabricated on the piping mock-up. The signals of guided ultrasonic waves from the artificial flaws will be analyzed. The guided ultrasonic techniques will be applied to the inspection of pipes of nuclear power plants according to the basis of signals analysis of artificial flaws in the piping mock-up

  18. Simulation of Distributed PV Power Output in Oahu Hawaii

    Energy Technology Data Exchange (ETDEWEB)

    Lave, Matthew Samuel [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2016-08-01

    Distributed solar photovoltaic (PV) power generation in Oahu has grown rapidly since 2008. For applications such as determining the value of energy storage, it is important to have PV power output timeseries. Since these timeseries of not typically measured, here we produce simulated distributed PV power output for Oahu. Simulated power output is based on (a) satellite-derived solar irradiance, (b) PV permit data by neighborhood, and (c) population data by census block. Permit and population data was used to model locations of distributed PV, and irradiance data was then used to simulate power output. PV power output simulations are presented by sub-neighborhood polygons, neighborhoods, and for the whole island of Oahu. Summary plots of annual PV energy and a sample week timeseries of power output are shown, and a the files containing the entire timeseries are described.

  19. Output power analyses for the thermodynamic cycles of thermal power plants

    International Nuclear Information System (INIS)

    Sun Chen; Cheng Xue-Tao; Liang Xin-Gang

    2014-01-01

    Thermal power plant is one of the important thermodynamic devices, which is very common in all kinds of power generation systems. In this paper, we use a new concept, entransy loss, as well as exergy destruction, to analyze the single reheating Rankine cycle unit and the single stage steam extraction regenerative Rankine cycle unit in power plants. This is the first time that the concept of entransy loss is applied to the analysis of the power plant Rankine cycles with reheating and steam extraction regeneration. In order to obtain the maximum output power, the operating conditions under variant vapor mass flow rates are optimized numerically, as well as the combustion temperatures and the off-design flow rates of the flue gas. The relationship between the output power and the exergy destruction rate and that between the output power and the entransy loss rate are discussed. It is found that both the minimum exergy destruction rate and the maximum entransy loss rate lead to the maximum output power when the combustion temperature and heat capacity flow rate of the flue gas are prescribed. Unlike the minimum exergy destruction rate, the maximum entransy loss rate is related to the maximum output power when the highest temperature and heat capacity flow rate of the flue gas are not prescribed. (general)

  20. A study on the diagnosis for power transformer by ultrasonic wave detection(2)

    International Nuclear Information System (INIS)

    Lee, Sang Guk; Gil Doo Song

    2003-01-01

    The objectives of this study is to develop a device which could diagnose periodically the degradation of power transformer using ultrasonic signal through ultrasonic transducer attached surface of power transformer. And also it makes possible to reduce power failure time due to the power transformer fault and makes power system more reliable. Ultrasonic diagnostic device for power transformer was developed through this study. The developed device will contributed to early detection of fault and its location in the power transformer while it is operated, and also to extension of transformer life cycle, localization of this device will be reduced it's cost down compared with off shore. This device consisted of a new diagnostic algorithm is well suited for the power transformer which could found out some fault during the operation of on line monitoring system. This system could be extended to the general industrial plant utilizing the accumulated diagnostic technique.

  1. A study on the diagnosis for power transformer by Ultrasonic wave detection (2)

    International Nuclear Information System (INIS)

    Lee, Sang Guk; Gil, Doo Song

    2003-01-01

    The objectives of this study is to develop a device which could diagnosis periodically the degradation of power transformer using ultrasonic signal through ultrasonic transducer attached surface of power transformer. And also it makes possible to reduce power failure time due to the power transformer fault and makes power system more reliable. Ultrasonic diagnostic device for power transformer was developed through this study. The developed device will contributed to early detection of fault and its location in the power transformer while it is operated, and also to extension of transformer life cycle, localization of this device will be reduced it's cost down compared with off shore. This device consisted of a new diagnostic algorithm is well suited for the power transformer which could found out some fault during the operation of on line monitoring system. This system could be extended to the general industrial plant utilizing the accumulated diagnostic technique.

  2. Ultrasonic power transfer from a spherical acoustic wave source to a free-free piezoelectric receiver: Modeling and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Shahab, S.; Gray, M.; Erturk, A., E-mail: alper.erturk@me.gatech.edu [G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

    2015-03-14

    Contactless powering of small electronic components has lately received growing attention for wireless applications in which battery replacement or tethered charging is undesired or simply impossible, and ambient energy harvesting is not a viable solution. As an alternative to well-studied methods of contactless energy transfer, such as the inductive coupling method, the use of ultrasonic waves transmitted and received by piezoelectric devices enables larger power transmission distances, which is critical especially for deep-implanted electronic devices. Moreover, energy transfer by means of acoustic waves is well suited in situations where no electromagnetic fields are allowed. The limited literature of ultrasonic acoustic energy transfer is mainly centered on proof-of-concept experiments demonstrating the feasibility of this method, lacking experimentally validated modeling efforts for the resulting multiphysics problem that couples the source and receiver dynamics with domain acoustics. In this work, we present fully coupled analytical, numerical, and experimental multiphysics investigations for ultrasonic acoustic energy transfer from a spherical wave source to a piezoelectric receiver bar that operates in the 33-mode of piezoelectricity. The fluid-loaded piezoelectric receiver under free-free mechanical boundary conditions is shunted to an electrical load for quantifying the electrical power output for a given acoustic source strength of the transmitter. The analytical acoustic-piezoelectric structure interaction modeling framework is validated experimentally, and the effects of system parameters are reported along with optimal electrical loading and frequency conditions of the receiver.

  3. Ultrasonic power transfer from a spherical acoustic wave source to a free-free piezoelectric receiver: Modeling and experiment

    International Nuclear Information System (INIS)

    Shahab, S.; Gray, M.; Erturk, A.

    2015-01-01

    Contactless powering of small electronic components has lately received growing attention for wireless applications in which battery replacement or tethered charging is undesired or simply impossible, and ambient energy harvesting is not a viable solution. As an alternative to well-studied methods of contactless energy transfer, such as the inductive coupling method, the use of ultrasonic waves transmitted and received by piezoelectric devices enables larger power transmission distances, which is critical especially for deep-implanted electronic devices. Moreover, energy transfer by means of acoustic waves is well suited in situations where no electromagnetic fields are allowed. The limited literature of ultrasonic acoustic energy transfer is mainly centered on proof-of-concept experiments demonstrating the feasibility of this method, lacking experimentally validated modeling efforts for the resulting multiphysics problem that couples the source and receiver dynamics with domain acoustics. In this work, we present fully coupled analytical, numerical, and experimental multiphysics investigations for ultrasonic acoustic energy transfer from a spherical wave source to a piezoelectric receiver bar that operates in the 33-mode of piezoelectricity. The fluid-loaded piezoelectric receiver under free-free mechanical boundary conditions is shunted to an electrical load for quantifying the electrical power output for a given acoustic source strength of the transmitter. The analytical acoustic-piezoelectric structure interaction modeling framework is validated experimentally, and the effects of system parameters are reported along with optimal electrical loading and frequency conditions of the receiver

  4. Development of a Multi-Channel Ultrasonic Testing System for Automated Ultrasonic Pipe Inspection of Nuclear Power Plant

    International Nuclear Information System (INIS)

    Lee, Hee Jong; Cho, Chan Hee; Cho, Hyun Joon

    2009-01-01

    Currently almost all in-service-inspection techniques, applied in domestic nuclear power plants, are partial to field inspection technique. These kinds of techniques are related to managing nuclear power plants by the operation of foreign-produced inspection devices. There have been so many needs for development of native in-service-inspection device because there is no native diagnosis device for nuclear power plant inspection yet in Korea. In this research, we developed several core techniques to make an automated ultrasonic pipe inspection system for nuclear power plants. A high performance multi-channel ultrasonic pulser/receiver module, an A/D converter module and a digital main CPU module were developed and the performance of the developed modules was verified. The S/N ratio, noise level and signal acquisition performance of the developed modules showed proper level as we designed in the beginning.

  5. Linear ultrasonic motor for absolute gravimeter.

    Science.gov (United States)

    Jian, Yue; Yao, Zhiyuan; Silberschmidt, Vadim V

    2017-05-01

    Thanks to their compactness and suitability for vacuum applications, linear ultrasonic motors are considered as substitutes for classical electromagnetic motors as driving elements in absolute gravimeters. Still, their application is prevented by relatively low power output. To overcome this limitation and provide better stability, a V-type linear ultrasonic motor with a new clamping method is proposed for a gravimeter. In this paper, a mechanical model of stators with flexible clamping components is suggested, according to a design criterion for clamps of linear ultrasonic motors. After that, an effect of tangential and normal rigidity of the clamping components on mechanical output is studied. It is followed by discussion of a new clamping method with sufficient tangential rigidity and a capability to facilitate pre-load. Additionally, a prototype of the motor with the proposed clamping method was fabricated and the performance tests in vertical direction were implemented. Experimental results show that the suggested motor has structural stability and high dynamic performance, such as no-load speed of 1.4m/s and maximal thrust of 43N, meeting the requirements for absolute gravimeters. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Generation of OH Radical by Ultrasonic Irradiation in Batch and Circulatory Reactor

    Science.gov (United States)

    Fang, Yu; Shimizu, Sayaka; Yamamoto, Takuya; Komarov, Sergey

    2018-03-01

    Ultrasonic technology has been widely investigated in the past as one of the advance oxidation processes to treat wastewater, in this process acoustic cavitation causes generation of OH radical, which play a vital role in improving the treatment efficiency. In this study, OH radical formation rate was measured in batch and circulatory reactor by using Weissler reaction at various ultrasound output power. It is found that the generation rate in batch reactor is higher than that in circulatory reactor at the same output power. The generation rate tended to be slower when output power exceeds 137W. The optimum condition for circulatory reactor was found to be 137W output and 4L/min flow rate. Results of aluminum foil erosion test revealed a strong dependence of cavitation zone length on the ultrasound output power. This is assumed to be one of the reasons why the generation rate of HO radicals becomes slower at higher output power in circulatory reactor.

  7. Lower sintering temperature of nanostructured dense ceramics compacted from dry nanopowders using powerful ultrasonic action

    OpenAIRE

    Khasanov, O.; Reichel, U.; Dvilis, E.; Khasanov, A.

    2011-01-01

    Nanostructured high dense zirconia ceramics have been sintered from dry nanopowders compacted by uniaxial pressing with simultaneous powerful ultrasonic action (PUA). Powerful ultrasound with frequency of 21 kHz was supplied from ultrasonic generator to the mold, which was the ultrasonic wave-guide. Previously the mold was filled by non-agglomerated zirconia nanopowder having average particle size of 40 nm. Any binders or plasticizers were excluded at nanopowder processing. Compaction pressur...

  8. LOAD THAT MAXIMIZES POWER OUTPUT IN COUNTERMOVEMENT JUMP

    Directory of Open Access Journals (Sweden)

    Pedro Jimenez-Reyes

    2016-02-01

    Full Text Available ABSTRACT Introduction: One of the main problems faced by strength and conditioning coaches is the issue of how to objectively quantify and monitor the actual training load undertaken by athletes in order to maximize performance. It is well known that performance of explosive sports activities is largely determined by mechanical power. Objective: This study analysed the height at which maximal power output is generated and the corresponding load with which is achieved in a group of male-trained track and field athletes in the test of countermovement jump (CMJ with extra loads (CMJEL. Methods: Fifty national level male athletes in sprinting and jumping performed a CMJ test with increasing loads up to a height of 16 cm. The relative load that maximized the mechanical power output (Pmax was determined using a force platform and lineal encoder synchronization and estimating the power by peak power, average power and flight time in CMJ. Results: The load at which the power output no longer existed was at a height of 19.9 ± 2.35, referring to a 99.1 ± 1% of the maximum power output. The load that maximizes power output in all cases has been the load with which an athlete jump a height of approximately 20 cm. Conclusion: These results highlight the importance of considering the height achieved in CMJ with extra load instead of power because maximum power is always attained with the same height. We advise for the preferential use of the height achieved in CMJEL test, since it seems to be a valid indicative of an individual's actual neuromuscular potential providing a valid information for coaches and trainers when assessing the performance status of our athletes and to quantify and monitor training loads, measuring only the height of the jump in the exercise of CMJEL.

  9. Plasma Sterilizer with Ultrasonic Cavitation

    International Nuclear Information System (INIS)

    Krasnyj, V.V.; Klosovsky, A.V.; Panasko, T.A.; Shvets, O.M.; Semenova, O.T.; Taran, V.S.; Tereshin, V.I.

    2006-01-01

    A sterilizer consists of ozone generator based on a barrier glow discharge with the flat electrodes covered with dielectric with a high-voltage pulsed power supply of up to 250 W (1). The sterilization camera is equipped with ultrasonic source with the power of 100 W. The experiments on the inactivation of bacteria of the Bacillus Cereus type were carried out in the distilled water saturated by ozone. Ozone concentration in the aqueous solution was 6 mg/liter with ozone concentration at the output of ozone generator 30 mg/liter. The complete inactivation of spores took 15 min

  10. A fully automated system for ultrasonic power measurement and simulation accordingly to IEC 61161:2006

    NARCIS (Netherlands)

    Costa-Felix, R.P.B.; Alvarenga, A.V.; Hekkenberg, R.

    2011-01-01

    The ultrasonic power measurement, worldwide accepted, standard is the IEC 61161, presently in its 2nd edition (2006), but under review. To fulfil its requirements, considering that a radiation force balance is to be used as ultrasonic power detector, a large amount of raw data (mass measurement)

  11. Measuring nuclear power plant output by neutrino detection

    International Nuclear Information System (INIS)

    Korovkin, V.A.; Kodanev, S.A.; Panashchenko, N.S.; Sokolov, D.A.; Solov'yanov, O.M.; Tverdovskii, N.D.; Yarichin, A.D.; Ketov, S.N.; Kopeikin, V.I.; Machulin, I.N.; Mikaelyan, L.A.; Sinev, V.V.

    1989-01-01

    Neutrino emission from a reactor is inseparably linked with the fission process of heavy nuclei: each fission contributes a specific amount to the overall power output and gives rise to neutrinos which are emitted by the fission fragments created. Using a detector to record the neutrino flux gives a curve for the number of nuclei undergoing fission and the reactor power output. The question of whether it is practically possible to make use of neutrino emission from reactors was first posed in the mid-70s in connection with preparations for neutrino research at the Roven nuclear power plant (RAES) and in 1986 at an IAEA symposium on the topic of guarantees. Since 1982, research has been carried on at RAES on the fundamental properties and interactions of neutrinos. Based on this research and in parallel with it, in 1983 specialists from the Kurchatov Nuclear Power Institute and RAES jointly conducted an experiment which demonstrated in principle the possibility of remotely measuring reactor power output using the neutrino emission. This experiment had extremely limited statistics and is of interest today as the first demonstration of practical usage of neutrino emission from a reactor. At present the statistics for detecting neutrino events have increased tenfold and experience in lengthy measurements has been accumulated. This allows better analysis for the possibilities of the method. This paper reviews neutrino detection, theoretical bases of the method, determining the fission scale values for converting a number of neutrinos into power output, and measuring the power output

  12. Computer-aided ultrasonic inspection of steam turbine rotors

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, K H; Weber, M; Weiss, M [GEC ALSTHOM Energie GmbH, Nuremberg (Germany)

    1999-12-31

    As the output and economic value of power plants increase, the detection and sizing of the type of flaws liable to occur in the rotors of turbines using ultrasonic methods assumes increasing importance. An ultrasonic inspection carried out at considerable expense is expected to bring to light all safety-relevant flaws and to enable their size to be determined so as to permit a fracture-mechanics analysis to assess the reliability of the rotor under all possible stresses arising in operation with a high degree of accuracy. The advanced computer-aided ultrasonic inspection of steam turbine rotors have improved reliability, accuracy and reproducibility of ultrasonic inspection. Further, there has been an improvement in the resolution of resolvable group indications by applying reconstruction and imagine methods. In general, it is also true for the advanced computer-aided ultrasonic inspection methods that, in the case of flaw-affected forgings, automated data acquisition provides a substantial rationalization and a significant documentation of the results for the fracture mechanics assessment compared to manual inspection. (orig.) 8 refs.

  13. Computer-aided ultrasonic inspection of steam turbine rotors

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, K.H.; Weber, M.; Weiss, M. [GEC ALSTHOM Energie GmbH, Nuremberg (Germany)

    1998-12-31

    As the output and economic value of power plants increase, the detection and sizing of the type of flaws liable to occur in the rotors of turbines using ultrasonic methods assumes increasing importance. An ultrasonic inspection carried out at considerable expense is expected to bring to light all safety-relevant flaws and to enable their size to be determined so as to permit a fracture-mechanics analysis to assess the reliability of the rotor under all possible stresses arising in operation with a high degree of accuracy. The advanced computer-aided ultrasonic inspection of steam turbine rotors have improved reliability, accuracy and reproducibility of ultrasonic inspection. Further, there has been an improvement in the resolution of resolvable group indications by applying reconstruction and imagine methods. In general, it is also true for the advanced computer-aided ultrasonic inspection methods that, in the case of flaw-affected forgings, automated data acquisition provides a substantial rationalization and a significant documentation of the results for the fracture mechanics assessment compared to manual inspection. (orig.) 8 refs.

  14. A fully automated system for ultrasonic power measurement and simulation accordingly to IEC 61161:2006

    International Nuclear Information System (INIS)

    Costa-Felix, Rodrigo P B; Alvarenga, Andre V; Hekkenberg, Rob

    2011-01-01

    The ultrasonic power measurement, worldwide accepted, standard is the IEC 61161, presently in its 2nd edition (2006), but under review. To fulfil its requirements, considering that a radiation force balance is to be used as ultrasonic power detector, a large amount of raw data (mass measurement) shall be collected as function of time to perform all necessary calculations and corrections. Uncertainty determination demands calculation effort of raw and processed data. Although it is possible to be undertaken in an old-fashion way, using spread sheets and manual data collection, automation software are often used in metrology to provide a virtually error free environment concerning data acquisition and repetitive calculations and corrections. Considering that, a fully automate ultrasonic power measurement system was developed and comprehensively tested. A 0,1 mg of precision balance model CP224S (Sartorius, Germany) was used as measuring device and a calibrated continuous wave ultrasound check source (Precision Acoustics, UK) was the device under test. A 150 ml container filled with degassed water and containing an absorbing target at the bottom was placed on the balance pan. Besides the feature of automation software, a routine of power measurement simulation was implemented. It was idealized as a teaching tool of how ultrasonic power emission behaviour is with a radiation force balance equipped with an absorbing target. Automation software was considered as an effective tool for speeding up ultrasonic power measurement, while allowing accurate calculation and attractive graphical partial and final results.

  15. An ultrasonic phased array applicator for deep localized hyperthermia

    International Nuclear Information System (INIS)

    Ocheltree, K.B.; Benkeser, P.J.; Foster, S.G.; Frizzell, L.A.; Cain, C.A.

    1984-01-01

    The use of an ultrasonic phased array applicator presents a major advantage over the fixed beam ultrasonic applicators which are typically used for clinical hyperthermia. Such an applicator allows focal region placement in the three dimensional treatment field by electronic steering instead of mechanical movement of the transducer assembly. The design of an array is discussed theoretically, considering that the constraints on grating lobes and power output for hyperthermic applications are quite different from those for imaging. The effects of various design parameters are discussed. Experimental results are presented for several arrays for frequencies under 1 Mhz

  16. A study on the ultrasonic measurement for damage evaluation of power plant bearing

    International Nuclear Information System (INIS)

    Lee, Sang Guk

    2004-01-01

    For the purpose of monitoring by ultrasonic test of the ball bearing conditions in rotating machinery, a system for their diagnosis was developed. Ultrasonic technique is used to detect abnormal conditions in the bearing system. And various data such as frequency spectrum, energy and amplitude of ultrasonic signals, and ultrasonic parameters were acquired during experiments with the simulated ball bearing system. Based on the above results and practical application for power plant, algorithms and judgement criteria for diagnosis system was established. Bearing diagnosis system is composed of four parts as follows : sensing part for ultrasonic sensor and preamplifier, signal processing part for measuring frequency spectrum, energy and amplitude, interface part for connecting ultrasonic signal to PC using A/D converter, graphic display and software part for display of bearing condition and for managing of diagnosis program

  17. Ultrasonic friction power during thermosonic Au and Cu ball bonding

    International Nuclear Information System (INIS)

    Shah, A; Mayer, M; Zhou, Y; Qin, I; Huynh, C; Meyer, M

    2010-01-01

    The ultrasonic friction power during thermosonic ball bonding with Au and Cu wires, both 25 μm in diameter, is derived with an improved method from experimental measurements during the bonding process. Experimental data include the current delivered to the ultrasonic transducer and the tangential force measured using piezoresistive microsensors integrated close to the Al bonding pad. The improvement results from a new, more accurate method to derive the mechanical compliance of the ultrasonic system. The method employs a bond process modification in which the ultrasonic current is ramped up sequentially in three steps. In the first two steps, the ultrasonic current is set to levels that are too low to cause sliding. The bonding takes place during the third step, when the current is ramped up to the optimum value required for making good quality bonds. The ultrasonic compliance values are derived from the first two steps and are 8.2 ± 0.5 μm N -1 and 7.7 ± 0.5 μm N -1 for the Au and Cu processes, respectively. These values are determined within an average error estimate of ±6%, substantially lower than the ±10% estimated with a previously reported method. The ultrasonic compliance in the case of Au is 6% higher due to the lower elastic modulus of Au compared with that of Cu. Typical maximum values of relative sliding amplitude of ultrasonic friction at the interface are 655 nm and 766 nm for the Au and Cu processes. These values are 81% of the free-air vibration amplitude of the bonding capillary tip for the respective ultrasonic current settings. Due to bond growth, which damps relative motion between the ball and the pad, the final relative amplitude at the bond interface is reduced to 4% of the equivalent free-air amplitude. Even though the maximum value of relative amplitude is 17% higher in the Cu process compared with the Au process, the average total interfacial sliding is 519 μm in the Cu process, which is 31% lower than that in the Au process (759

  18. Physicochemical changes and microbial inactivation after high-intensity ultrasound processing of prebiotic whey beverage applying different ultrasonic power levels.

    Science.gov (United States)

    Guimarães, Jonas T; Silva, Eric Keven; Alvarenga, Verônica O; Costa, Ana Letícia R; Cunha, Rosiane L; Sant'Ana, Anderson S; Freitas, Monica Q; Meireles, M Angela A; Cruz, Adriano G

    2018-06-01

    In this work, we investigated the effects of the ultrasonic power (0, 200, 400 and 600 W) on non-thermal processing of an inulin-enriched whey beverage. We studied the effects of high-intensity ultrasound (HIUS) on microbial inactivation (aerobic mesophilic heterotrophic bacteria (AMHB), total and thermotolerant coliforms and yeasts and molds), zeta potential, microstructure (optical microscopy, particle size distribution), rheology, kinetic stability and color. The non-thermal processing applying 600 W of ultrasonic power was comparable to high-temperature short-time (HTST) treatment (75 °C for 15 s) concerning the inactivation of AMHB and yeasts and molds (2 vs 2 log and 0.2 vs 0.4 log, respectively), although HIUS has reached a lower output temperature (53 ± 3 °C). The HIUS was better than HTST to improve beverage kinetic stability, avoiding phase separation, which was mainly attributed to the decrease of particles size, denaturation of whey proteins and gelation of polysaccharides (inulin and gellan gum). Thus, non-thermal processing by HIUS seems to be an interesting technology for prebiotic dairy beverages production. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Innovative ultrasonics for power plant commissioning

    International Nuclear Information System (INIS)

    Murphy, R.V.; Alikhan, S.

    1983-05-01

    During the commissioning of a nuclear power plant, the usual role of ultrasonics is associated with nondestructive testing of welds. There is, however, a variety of undesirable conditions associated with the fluids carried through the various reactor systems which may be just as important to station operation. A variety of unusual ultrasonic techniques has been developed for testing fluid systems at the Point Lepreau Generating Station. This paper uses the experience gained at the Point Lepreau reactor to illustrate the valuable information which can be gained from these measurements, such as: fluid level in pipes and headers; fluid level in pressure vessels; detection, and sizing of debris in pipes; in situ measurement and verification of orifice condition; detection and location of cavitation, water hammer, valve leakage; quantitative measurement of gate movement within the body of an inservice valve; determination of valve position; detection and imaging of flow separation; detection and location of leaks in concrete containment structures; verification of design flows; balancing of loop flows; and detection of low flow. The application of these techniques at other reactor sites is also discussed

  20. Reactive Power Pricing Model Considering the Randomness of Wind Power Output

    Science.gov (United States)

    Dai, Zhong; Wu, Zhou

    2018-01-01

    With the increase of wind power capacity integrated into grid, the influence of the randomness of wind power output on the reactive power distribution of grid is gradually highlighted. Meanwhile, the power market reform puts forward higher requirements for reasonable pricing of reactive power service. Based on it, the article combined the optimal power flow model considering wind power randomness with integrated cost allocation method to price reactive power. Meanwhile, considering the advantages and disadvantages of the present cost allocation method and marginal cost pricing, an integrated cost allocation method based on optimal power flow tracing is proposed. The model realized the optimal power flow distribution of reactive power with the minimal integrated cost and wind power integration, under the premise of guaranteeing the balance of reactive power pricing. Finally, through the analysis of multi-scenario calculation examples and the stochastic simulation of wind power outputs, the article compared the results of the model pricing and the marginal cost pricing, which proved that the model is accurate and effective.

  1. Lower sintering temperature of nanostructured dense ceramics compacted from dry nanopowders using powerful ultrasonic action

    Science.gov (United States)

    Khasanov, O.; Reichel, U.; Dvilis, E.; Khasanov, A.

    2011-10-01

    Nanostructured high dense zirconia ceramics have been sintered from dry nanopowders compacted by uniaxial pressing with simultaneous powerful ultrasonic action (PUA). Powerful ultrasound with frequency of 21 kHz was supplied from ultrasonic generator to the mold, which was the ultrasonic wave-guide. Previously the mold was filled by non-agglomerated zirconia nanopowder having average particle size of 40 nm. Any binders or plasticizers were excluded at nanopowder processing. Compaction pressure was 240 MPa, power of ultrasonic generator at PUA was 1 kW and 3 kW. The fully dense zirconia ceramics has been sintered at 1345°C and high-dense ceramics with a density of 99.1%, the most grains of which had the sizes Dgr <= 200 nm, has been sintered at low sintering temperature (1325°C). Applied approach prevents essential grain growth owing to uniform packing of nanoparticles under vibrating PU-action at pressing, which provides the friction forces control during dry nanopowder compaction without contaminating binders or plasticizers.

  2. Compensating for Tissue Changes in an Ultrasonic Power Link for Implanted Medical Devices.

    Science.gov (United States)

    Vihvelin, Hugo; Leadbetter, Jeff; Bance, Manohar; Brown, Jeremy A; Adamson, Robert B A

    2016-04-01

    Ultrasonic power transfer using piezoelectric devices is a promising wireless power transfer technology for biomedical implants. However, for sub-dermal implants where the separation between the transmitter and receiver is on the order of several acoustic wavelengths, the ultrasonic power transfer efficiency (PTE) is highly sensitive to the distance between the transmitter and receiver. This sensitivity can cause large swings in efficiency and presents a serious limitation on battery life and overall performance. A practical ultrasonic transcutaneous energy transfer (UTET) system design must accommodate different implant depths and unpredictable acoustic changes caused by tissue growth, hydration, ambient temperature, and movement. This paper describes a method used to compensate for acoustic separation distance by varying the transmit (Tx) frequency in a UTET system. In a benchtop UTET system we experimentally show that without compensation, power transfer efficiency can range from 9% to 25% as a 5 mm porcine tissue sample is manipulated to simulate in situ implant conditions. Using an active frequency compensation method, we show that the power transfer efficiency can be kept uniformly high, ranging from 20% to 27%. The frequency compensation strategy we propose is low-power, non-invasive, and uses only transmit-side measurements, making it suitable for active implanted medical device applications.

  3. Ultrasonic meters in the feedwater flow to recover thermal power in the reactor of nuclear power plant of Laguna Verde U1 and U2

    International Nuclear Information System (INIS)

    Tijerina S, F.

    2008-01-01

    The engineers in nuclear power plants BWRs and PWRs based on the development of the ultrasonic technology for the measurement of the mass, volumetric flow, density and temperature in fluids, have applied this technology in two primary targets approved by the NRC: the use for the recovery of thermal power in the reactor and/or to be able to realize an increase of thermal power licensed in a 2% (MUR) by 1OCFR50 Appendix K. The present article mentions the current problem in the measurement of the feedwater flow with Venturi meters, which affects that the thermal balance of reactor BWRs or PWRs this underestimated. One in broad strokes describes the application of the ultrasonic technology for the ultrasonic measurement in the flow of the feedwater system of the reactor and power to recover thermal power of the reactor. One is to the methodology developed in CFE for a calibration of the temperature transmitters of RTD's and the methodology for a calibration of the venturi flow transmitters using ultrasonic measurement. Are show the measurements in the feedwater of reactor of the temperature with RTD's and ultrasonic measurement, as well as the flow with the venturi and the ultrasonic measurement operating the reactor to the 100% of nominal thermal power, before and after the calibration of the temperature transmitters and flow. Finally, is a plan to be able to realize a recovery of thermal power of the reactor, showing as carrying out their estimations. As a result of the application of ultrasonic technology in the feedwater of reactor BWR-5 in Laguna Verde, in the Unit 1 cycle 13 it was recover an equivalent energy to a thermal power of 25 MWt in the reactor and an exit electrical power of 6 M We in the turbogenerator. Also in the Unit 2 cycle 10 it was recover an equivalent energy to a thermal power of 40 MWt in the reactor and an exit electrical power of 16 M We in the turbogenerator. (Author)

  4. Complementary power output characteristics of electromagnetic generators and triboelectric generators.

    Science.gov (United States)

    Fan, Feng-Ru; Tang, Wei; Yao, Yan; Luo, Jianjun; Zhang, Chi; Wang, Zhong Lin

    2014-04-04

    Recently, a triboelectric generator (TEG) has been invented to convert mechanical energy into electricity by a conjunction of triboelectrification and electrostatic induction. Compared to the traditional electromagnetic generator (EMG) that produces a high output current but low voltage, the TEG has different output characteristics of low output current but high output voltage. In this paper, we present a comparative study regarding the fundamentals of TEGs and EMGs. The power output performances of the EMG and the TEG have a special complementary relationship, with the EMG being a voltage source and the TEG a current source. Utilizing a power transformed and managed (PTM) system, the current output of a TEG can reach as high as ∼3 mA, which can be coupled with the output signal of an EMG to enhance the output power. We also demonstrate a design to integrate a TEG and an EMG into a single device for simultaneously harvesting mechanical energy. In addition, the integrated NGs can independently output a high voltage and a high current to meet special needs.

  5. An ultrasonic inspection tool for production tubulars

    Energy Technology Data Exchange (ETDEWEB)

    Newton, K; Martin, R; Ravenscroft, F [AEA Technology, Harwell (United Kingdom)

    1994-06-01

    Advances in ultrasonic technology, high temperature techniques and remote processing power are enabling a new generation of inspection tools to be developed. This paper describes a particular new ultrasonic caliper system, developed by AEA Technology, with the aim of providing improved information about the condition of production tubulars of oil and gas wells. The system is designed to provide enhanced surface area coverage compared to the current devices, which are typically mechanical 'finger' calipers. It also provides a non-contacting measure of corrosion and wear together with direct on-line output and automated data analysis. The new tool is designed to operate in oil and gas, vertical or deviated wells and has the potential for modification to inspect small diameter pipes in topside or other plant. (author)

  6. Auxetic piezoelectric energy harvesters for increased electric power output

    Directory of Open Access Journals (Sweden)

    Qiang Li

    2017-01-01

    Full Text Available This letter presents a piezoelectric bimorph with auxetic (negative Poisson’s ratio behaviors for increased power output in vibration energy harvesting. The piezoelectric bimorph comprises a 2D auxetic substrate sandwiched between two piezoelectric layers. The auxetic substrate is capable of introducing auxetic behaviors and thus increasing the transverse stress in the piezoelectric layers when the bimorph is subjected to a longitudinal stretching load. As a result, both 31- and 32-modes are simultaneously exploited to generate electric power, leading to an increased power output. The increasing power output principle was theoretically analyzed and verified by finite element (FE modelling. The FE modelling results showed that the auxetic substrate can increase the transverse stress of a bimorph by 16.7 times. The average power generated by the auxetic bimorph is 2.76 times of that generated by a conventional bimorph.

  7. Effect of focused ultrasound stimulation at different ultrasonic power levels on the local field potential power spectrum

    International Nuclear Information System (INIS)

    Yuan Yi; Lu Cheng-Biao; Li Xiao-Li

    2015-01-01

    Local field potential (LFP) signals of the rat hippocampus were recorded under noninvasive focused ultrasound stimulation (FUS) with different ultrasonic powers. The LFP mean absolute power was calculated with the Welch algorithm at the delta, theta, alpha, beta, and gamma frequency bands. The experimental results demonstrate that the LFP mean absolute power at different frequency bands increases as the ultrasound power increases. (paper)

  8. Enhancing gas-phase reaction in a plasma using high intensity and high power ultrasonic acoustic waves

    DEFF Research Database (Denmark)

    2010-01-01

    is absorbed into said plasma (104), and where a sound pressure level of said generated ultrasonic high intensity and high power acoustic waves (102) is at least substantially 140 dB and where an acoustic power of said generated ultrasonic high intensity and high power acoustic waves (102); is at least...... substantially 100 W. In this way, a high sound intensity and power are obtained that efficiently enhances a gas-phase reaction in the plasma, which enhances the plasma process, e.g. enabling more efficient ozone or hydrogen generation using plasma in relation to reaction speed and/or obtained concentration......This invention relates to enhancing a gas-phase reaction in a plasma comprising: creating plasma (104) by at least one plasma source (106), and wherein that the method further comprises: generating ultrasonic high intensity and high power acoustic waves (102) having a predetermined amount...

  9. Standing wave brass-PZT square tubular ultrasonic motor.

    Science.gov (United States)

    Park, Soonho; He, Siyuan

    2012-09-01

    This paper reports a standing wave brass-PZT tubular ultrasonic motor. The motor is composed of a brass square tube with two teeth on each tube end. Four PZT plates are attached to the outside walls of the brass tube. The motor requires only one driving signal to excite vibration in a single bending mode to generate reciprocating diagonal trajectories of teeth on the brass tube ends, which drive the motor to rotate. Bi-directional rotation is achieved by exciting different pairs of PZT plates to switch the bending vibration direction. Through using the brass-PZT tube structure, the motor can take high magnitude vibration to achieve a high output power in comparison to PZT tube based ultrasonic motors. Prototypes are fabricated and tested. The dimension of the brass-PZT tube is 3.975mm×3.975mm×16mm. Measured performance is a no-load speed of >1000RPM, a stall torque of 370μNm and a maximum output power of 16 mW when a sinusoidal driving voltage of 50V is applied. The working frequencies of the motor are 46,050Hz (clockwise) and 46,200Hz (counter-clockwise). Copyright © 2012. Published by Elsevier B.V.

  10. Output power distributions of terminals in a 3G mobile communication network.

    Science.gov (United States)

    Persson, Tomas; Törnevik, Christer; Larsson, Lars-Eric; Lovén, Jan

    2012-05-01

    The objective of this study was to examine the distribution of the output power of mobile phones and other terminals connected to a 3G network in Sweden. It is well known that 3G terminals can operate with very low output power, particularly for voice calls. Measurements of terminal output power were conducted in the Swedish TeliaSonera 3G network in November 2008 by recording network statistics. In the analysis, discrimination was made between rural, suburban, urban, and dedicated indoor networks. In addition, information about terminal output power was possible to collect separately for voice and data traffic. Information from six different Radio Network Controllers (RNCs) was collected during at least 1 week. In total, more than 800000 h of voice calls were collected and in addition to that a substantial amount of data traffic. The average terminal output power for 3G voice calls was below 1 mW for any environment including rural, urban, and dedicated indoor networks. This is <1% of the maximum available output power. For data applications the average output power was about 6-8 dB higher than for voice calls. For rural areas the output power was about 2 dB higher, on average, than in urban areas. Copyright © 2011 Wiley Periodicals, Inc.

  11. Optimization of output power and transmission efficiency of magnetically coupled resonance wireless power transfer system

    Science.gov (United States)

    Yan, Rongge; Guo, Xiaoting; Cao, Shaoqing; Zhang, Changgeng

    2018-05-01

    Magnetically coupled resonance (MCR) wireless power transfer (WPT) system is a promising technology in electric energy transmission. But, if its system parameters are designed unreasonably, output power and transmission efficiency will be low. Therefore, optimized parameters design of MCR WPT has important research value. In the MCR WPT system with designated coil structure, the main parameters affecting output power and transmission efficiency are the distance between the coils, the resonance frequency and the resistance of the load. Based on the established mathematical model and the differential evolution algorithm, the change of output power and transmission efficiency with parameters can be simulated. From the simulation results, it can be seen that output power and transmission efficiency of the two-coil MCR WPT system and four-coil one with designated coil structure are improved. The simulation results confirm the validity of the optimization method for MCR WPT system with designated coil structure.

  12. Ultrasonic level and temperature sensor for power reactor applications

    International Nuclear Information System (INIS)

    Dress, W.B.; Miller, G.N.

    1983-01-01

    An ultrasonic waveguide employing torsional and extensional acoustic waves has been developed for use as a level and temperature sensor in pressurized and boiling water nuclear power reactors. Features of the device include continuous measurement of level, density, and temperature producing a real-time profile of these parameters along a chosen path through the reactor vessel

  13. Intermittent Smoothing Approaches for Wind Power Output: A Review

    Directory of Open Access Journals (Sweden)

    Muhammad Jabir

    2017-10-01

    Full Text Available Wind energy is one of the most common types of renewable energy resource. Due to its sustainability and environmental benefits, it is an emerging source for electric power generation. Rapid and random changes of wind speed makes it an irregular and inconsistent power source when connected to the grid, causing different technical problems in protection, power quality and generation dispatch control. Due to these problems, effective intermittent smoothing approaches for wind power output are crucially needed to minimize such problems. This paper reviews various intermittent smoothing approaches used in smoothing the output power fluctuations caused by wind energy. Problems associated with the inclusion of wind energy resources to grid are also briefly reviewed. From this review, it has been found that battery energy storage system is the most suitable and effective smoothing approach, provided that an effective control strategy is available for optimal utilization of battery energy system. This paper further demonstrates different control strategies built for battery energy storage system to obtain the smooth output wind power.

  14. Design and characterization of an ultrasonic lamb-wave power delivery system.

    Science.gov (United States)

    Kural, Aleksander; Pullin, Rhys; Holford, Karen; Lees, Jonathan; Naylon, Jack; Paget, Christophe; Featherston, Carol

    2013-06-01

    In this paper, a novel design for an ultrasonic power transmission system designed for use in aircraft structural monitoring systems is described. The prototype system uses ultrasonic Lamb waves to carry energy along plates, such as those used in aircraft structures, and commercially available piezoelectric patch transducers as the transmitter and receiver. This sets it apart from other acoustic power transmission systems reported to date. The optimum configuration transmitted 12.7 mW of power across a distance of 54 cm in a 1.5-mm-thick aluminum plate, while being driven by a 20-Vpp, 35-kHz sinusoidal electric signal. This is in the same order of magnitude as the power required by the wireless sensors nodes of a structural health monitoring system currently being developed by Cardiff University and its partners. Thus, the power transmission system can be considered a viable component of the power source combination considered for the sensor nodes, which will also include vibration and thermal energy harvesting. The paper describes the design and optimization of the transmission and reception circuits with the use of inductive compensation. The use of laser vibrometry to characterize the transducers and to understand the signal propagation between them is also reported.

  15. Enhancing Plasma Surface Modification using high Intensity and high Power Ultrasonic Acoustic Waves

    DEFF Research Database (Denmark)

    2010-01-01

    high intensity and high power acoustic waves (102) by at least one ultrasonic high intensity and high power acoustic wave generator (101 ), wherein the ultrasonic acoustic waves are directed to propagate towards said surface (314) of the object (100) so that a laminar boundary layer (313) of a gas...... or a mixture of gases (500) flow in contact with said solid object (100) is thinned or destructed for at least a part of said surface (314). In this way, the plasma can more efficiently access and influence the surface of the solid object to be treated by the plasma, which speeds the process time up...

  16. Development of an ultrasonic flow and temperature measurement system for pressurized water reactors

    International Nuclear Information System (INIS)

    James, R.W.; Lubnow, T.; Baumgart, G.; Ravetti, D.

    1996-01-01

    In U.S. nuclear plants, primary coolant flow and reactor thermal power are calculated from a measurement of feedwater flow to the steam generator combined with knowledge of steam generator heat transfer characteristics nd measurement of hot leg temperature by resistance temperature detectors (RTDs). The calculation of plant thermal output is complicated by an indirect measurement of primary coolant mass flow rate and thermal streaming in the region where hot leg temperature is typically measured. Uncertainty in the thermal output calculation results from uncertainties in steam generator characteristics, in the hot leg temperature due to thermal streaming, and in fouling of venturi nozzles used for feedwater flow measurement. This in turn leads to operation of power plants ar lower levels of efficiency. The Electric Power Research Institute (EPRI) has on ongoing project to develop a prototype system to directly measure primary coolant flow rate and bulk average temperature using ultrasonic transducers externally mounted on the pipe. The topic of this paper is a summary of the project experience in developing this system. The technology being developed in this project is based in part upon previously existing ultrasonic feedwater flow measurement technology developed by MPR Associates and Caldon, Inc EPRI is a non-profit company performing research for U.S. and international electric power utilities. (authors)

  17. Output power distributions of mobile radio base stations based on network measurements

    International Nuclear Information System (INIS)

    Colombi, D; Thors, B; Persson, T; Törnevik, C; Wirén, N; Larsson, L-E

    2013-01-01

    In this work output power distributions of mobile radio base stations have been analyzed for 2G and 3G telecommunication systems. The approach is based on measurements in selected networks using performance surveillance tools part of the network Operational Support System (OSS). For the 3G network considered, direct measurements of output power levels were possible, while for the 2G networks, output power levels were estimated from measurements of traffic volumes. Both voice and data services were included in the investigation. Measurements were conducted for large geographical areas, to ensure good overall statistics, as well as for smaller areas to investigate the impact of different environments. For high traffic hours, the 90th percentile of the averaged output power was found to be below 65% and 45% of the available output power for the 2G and 3G systems, respectively.

  18. Output power distributions of mobile radio base stations based on network measurements

    Science.gov (United States)

    Colombi, D.; Thors, B.; Persson, T.; Wirén, N.; Larsson, L.-E.; Törnevik, C.

    2013-04-01

    In this work output power distributions of mobile radio base stations have been analyzed for 2G and 3G telecommunication systems. The approach is based on measurements in selected networks using performance surveillance tools part of the network Operational Support System (OSS). For the 3G network considered, direct measurements of output power levels were possible, while for the 2G networks, output power levels were estimated from measurements of traffic volumes. Both voice and data services were included in the investigation. Measurements were conducted for large geographical areas, to ensure good overall statistics, as well as for smaller areas to investigate the impact of different environments. For high traffic hours, the 90th percentile of the averaged output power was found to be below 65% and 45% of the available output power for the 2G and 3G systems, respectively.

  19. Ultrasonic propulsion of kidney stones.

    Science.gov (United States)

    May, Philip C; Bailey, Michael R; Harper, Jonathan D

    2016-05-01

    Ultrasonic propulsion is a novel technique that uses short bursts of focused ultrasonic pulses to reposition stones transcutaneously within the renal collecting system and ureter. The purpose of this review is to discuss the initial testing of effectiveness and safety, directions for refinement of technique and technology, and opinions on clinical application. Preclinical studies with a range of probes, interfaces, and outputs have demonstrated feasibility and consistent safety of ultrasonic propulsion with room for increased outputs and refinement toward specific applications. Ultrasonic propulsion was used painlessly and without adverse events to reposition stones in 14 of 15 human study participants without restrictions on patient size, stone size, or stone location. The initial feasibility study showed applicability in a range of clinically relevant situations, including facilitating passage of residual fragments following ureteroscopy or shock wave lithotripsy, moving a large stone at the ureteropelvic junction with relief of pain, and differentiating large stones from a collection of small fragments. Ultrasonic propulsion shows promise as an office-based system for transcutaneously repositioning kidney stones. Potential applications include facilitating expulsion of residual fragments following ureteroscopy or shock wave lithotripsy, repositioning stones prior to treatment, and repositioning obstructing ureteropelvic junction stones into the kidney to alleviate acute renal colic.

  20. Enhancing reliability of ultrasonic testing of welds of nuclear power plant equipment

    International Nuclear Information System (INIS)

    Shcherbinskij, V.G.

    1981-01-01

    Results of investigation of factors influencing the reliability of manual ultrasonic testing of welded joints and weld deposited metal power-generating equipment are presented. Recommendations on the enhancing of reliability are given [ru

  1. Predicting Output Power for Nearshore Wave Energy Harvesting

    Directory of Open Access Journals (Sweden)

    Henock Mamo Deberneh

    2018-04-01

    Full Text Available Energy harvested from a Wave Energy Converter (WEC varies greatly with the location of its installation. Determining an optimal location that can result in maximum output power is therefore critical. In this paper, we present a novel approach to predicting the output power of a nearshore WEC by characterizing ocean waves using floating buoys. We monitored the movement of the buoys using an Arduino-based data collection module, including a gyro-accelerometer sensor and a wireless transceiver. The collected data were utilized to train and test prediction models. The models were developed using machine learning algorithms: SVM, RF and ANN. The results of the experiments showed that measurements from the data collection module can yield a reliable predictor of output power. Furthermore, we found that the predictors work better when the regressors are combined with a classifier. The accuracy of the proposed prediction model suggests that it could be extremely useful in both locating optimal placement for wave energy harvesting plants and designing the shape of the buoys used by them.

  2. Experimental study of defoaming by air-borne power ultrasonic technology

    Science.gov (United States)

    Rodríguez, Germán; Riera, Enrique; Gallego-Juárez, Juan A.; Acosta, Víctor M.; Pinto, Alberto; Martínez, Ignacio; Blanco, Alfonso

    2010-01-01

    Foam is a dispersion of gas in a liquid in which the distances between the gas bubbles are very small. Foams are frequently generated in the manufacture of many products as result from the aeration and agitation of liquids, from the vaporization of the liquid and also from biological or chemical reactions. Foams are generally an unwanted product in industrial processes because they cause difficulties in process control and in equipment operation. The most efficient conventional method for defoaming is the use of chemical agents but they contaminate the product. High-intensity ultrasonic waves offer a clean procedure to break foam bubbles. The potential use of ultrasound for foam breaking that was known since many years has been recently reinforced by the application of a new type of ultrasonic defoamer based on the stepped-plate high-power transducers to generate air-borne ultrasound. This defoamer has been successfully applied in several industrial problems such as the control of excess foam produced during the filling operation of bottles and cans on high-speed canning lines and in fermenting vessels and other reactors of great dimensions. The treatment of such industrial problems requires the proper characterization and quantification of the main parameters involved in the mechanisms of the defoaming effect. This paper deals with an experimental study about the separate influence of such parameters with the aim of improving the application of the stepped-plate power ultrasonic generators for the production of the defoaming action on industrial processes

  3. Optimization design of high power ultrasonic circular ring radiator in coupled vibration.

    Science.gov (United States)

    Xu, Long; Lin, Shuyu; Hu, Wenxu

    2011-10-01

    This paper presents a new high power ultrasonic (HPU) radiator, which consists of a transducer, an ultrasonic horn, and a metal circular ring. Both the transducer and horn in longitudinal vibrations are used to drive a metal circular ring in a radial-axial coupled vibration. This coupled vibration cannot only generate ultrasound in both the radial and axial directions, but also focus the ultrasound inside the circular ring. Except for the radial-axial coupled vibration mode, the third longitudinal harmonic vibration mode with relative large vibration amplitude is also detected, which can be used as another operation mode. Overall, the HPU with these two vibration modes should have good potential to be applied in liquid processing, such as sonochemistry, ultrasonic cleaning, and Chinese herbal medicine extraction. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Artificial Neural Networks to Predict the Power Output of a PV Panel

    Directory of Open Access Journals (Sweden)

    Valerio Lo Brano

    2014-01-01

    Full Text Available The paper illustrates an adaptive approach based on different topologies of artificial neural networks (ANNs for the power energy output forecasting of photovoltaic (PV modules. The analysis of the PV module’s power output needed detailed local climate data, which was collected by a dedicated weather monitoring system. The Department of Energy, Information Engineering, and Mathematical Models of the University of Palermo (Italy has built up a weather monitoring system that worked together with a data acquisition system. The power output forecast is obtained using three different types of ANNs: a one hidden layer Multilayer perceptron (MLP, a recursive neural network (RNN, and a gamma memory (GM trained with the back propagation. In order to investigate the influence of climate variability on the electricity production, the ANNs were trained using weather data (air temperature, solar irradiance, and wind speed along with historical power output data available for the two test modules. The model validation was performed by comparing model predictions with power output data that were not used for the network's training. The results obtained bear out the suitability of the adopted methodology for the short-term power output forecasting problem and identified the best topology.

  5. Hand Gesture Recognition Using Ultrasonic Waves

    KAUST Repository

    AlSharif, Mohammed Hussain

    2016-04-01

    Gesturing is a natural way of communication between people and is used in our everyday conversations. Hand gesture recognition systems are used in many applications in a wide variety of fields, such as mobile phone applications, smart TVs, video gaming, etc. With the advances in human-computer interaction technology, gesture recognition is becoming an active research area. There are two types of devices to detect gestures; contact based devices and contactless devices. Using ultrasonic waves for determining gestures is one of the ways that is employed in contactless devices. Hand gesture recognition utilizing ultrasonic waves will be the focus of this thesis work. This thesis presents a new method for detecting and classifying a predefined set of hand gestures using a single ultrasonic transmitter and a single ultrasonic receiver. This method uses a linear frequency modulated ultrasonic signal. The ultrasonic signal is designed to meet the project requirements such as the update rate, the range of detection, etc. Also, it needs to overcome hardware limitations such as the limited output power, transmitter, and receiver bandwidth, etc. The method can be adapted to other hardware setups. Gestures are identified based on two main features; range estimation of the moving hand and received signal strength (RSS). These two factors are estimated using two simple methods; channel impulse response (CIR) and cross correlation (CC) of the reflected ultrasonic signal from the gesturing hand. A customized simple hardware setup was used to classify a set of hand gestures with high accuracy. The detection and classification were done using methods of low computational cost. This makes the proposed method to have a great potential for the implementation in many devices including laptops and mobile phones. The predefined set of gestures can be used for many control applications.

  6. Direct-current nanogenerator driven by ultrasonic waves.

    Science.gov (United States)

    Wang, Xudong; Song, Jinhui; Liu, Jin; Wang, Zhong Lin

    2007-04-06

    We have developed a nanowire nanogenerator that is driven by an ultrasonic wave to produce continuous direct-current output. The nanogenerator was fabricated with vertically aligned zinc oxide nanowire arrays that were placed beneath a zigzag metal electrode with a small gap. The wave drives the electrode up and down to bend and/or vibrate the nanowires. A piezoelectric-semiconducting coupling process converts mechanical energy into electricity. The zigzag electrode acts as an array of parallel integrated metal tips that simultaneously and continuously create, collect, and output electricity from all of the nanowires. The approach presents an adaptable, mobile, and cost-effective technology for harvesting energy from the environment, and it offers a potential solution for powering nanodevices and nanosystems.

  7. Multi-decadal Variability of the Wind Power Output

    Science.gov (United States)

    Kirchner Bossi, Nicolas; García-Herrera, Ricardo; Prieto, Luis; Trigo, Ricardo M.

    2014-05-01

    The knowledge of the long-term wind power variability is essential to provide a realistic outlook on the power output during the lifetime of a planned wind power project. In this work, the Power Output (Po) of a market wind turbine is simulated with a daily resolution for the period 1871-2009 at two different locations in Spain, one at the Central Iberian Plateau and another at the Gibraltar Strait Area. This is attained through a statistical downscaling of the daily wind conditions. It implements a Greedy Algorithm as classificator of a geostrophic-based wind predictor, which is derived by considering the SLP daily field from the 56 ensemble members of the longest homogeneous reanalysis available (20CR, 1871-2009). For calibration and validation purposes we use 10 years of wind observations (the predictand) at both sites. As a result, a series of 139 annual wind speed Probability Density Functions (PDF) are obtained, with a good performance in terms of wind speed uncertainty reduction (average daily wind speed MAE=1.48 m/s). The obtained centennial series allow to investigate the multi-decadal variability of wind power from different points of view. Significant periodicities around the 25-yr frequency band, as well as long-term linear trends are detected at both locations. In addition, a negative correlation is found between annual Po at both locations, evidencing the differences in the dynamical mechanisms ruling them (and possible complementary behavior). Furthermore, the impact that the three leading large-scale circulation patterns over Iberia (NAO, EA and SCAND) exert over wind power output is evaluated. Results show distinct (and non-stationary) couplings to these forcings depending on the geographical position and season or month. Moreover, significant non-stationary correlations are observed with the slow varying Atlantic Multidecadal Oscillation (AMO) index for both case studies. Finally, an empirical relationship is explored between the annual Po and the

  8. Carnot efficiency at divergent power output

    Science.gov (United States)

    Polettini, Matteo; Esposito, Massimiliano

    2017-05-01

    The widely debated feasibility of thermodynamic machines achieving Carnot efficiency at finite power has been convincingly dismissed. Yet, the common wisdom that efficiency can only be optimal in the limit of infinitely slow processes overlooks the dual scenario of infinitely fast processes. We corroborate that efficient engines at divergent power output are not theoretically impossible, framing our claims within the theory of Stochastic Thermodynamics. We inspect the case of an electronic quantum dot coupled to three particle reservoirs to illustrate the physical rationale.

  9. Ultrasonic thermometry for nuclear power plants

    International Nuclear Information System (INIS)

    Saravana Kumar, S.; Arunraj, A.L.R.; Swaminathan, K.

    2013-01-01

    Ultrasonic transducer provides a method of measurement of temperature in industrial tanks and boilers containing different liquids with varied salt content. This method is used to measure the average temperature continuously where other traditional methods available do not offer. Traditional methods used for temperature measurement like infrared thermometers, thermocouples, measures temperature at a single location. Numerous thermocouples are to be fixed at various part of the boiler in order to measure the temperature of the entire boiler, which incurs high cost. Reliability of the system decreases, with increasing number of thermocouples. When they fail at a point, the time incurred in finding the faulty part or faulty thermocouple is high. Ultrasonic transducer provides continuous measurement for all different characteristic liquids with higher accuracy and lesser response time. Fault location and clearance time is also less in ultrasonic measurement method, since only a couple of transducers used for the entire boiler structure. Additionally ultrasonic thermometry along support measuring electronic system can be built of low cost. (author)

  10. Estimation of the Maximum Output Power of Double-Clad Photonic Crystal Fiber Laser

    International Nuclear Information System (INIS)

    Chen Yue-E; Wang Yong; Qu Xi-Long

    2012-01-01

    Compared with traditional optical fiber lasers, double-clad photonic crystal fiber (PCF) lasers have larger surface-area-to-volume ratios. With an increase of output power, thermal effects may severely restrict output power and deteriorate beam quality of fiber lasers. We utilize the heat-conduction equations to estimate the maximum output power of a double-clad PCF laser under natural-convection, air-cooling, and water-cooling conditions in terms of a certain surface-volume heat ratio of the PCF. The thermal effects hence define an upper power limit of double-clad PCF lasers when scaling output power. (fundamental areas of phenomenology(including applications))

  11. Modeling the power output of piezoelectric energy harvesters

    KAUST Repository

    Al Ahmad, Mahmoud

    2011-04-30

    Design of experiments and multiphysics analyses were used to develop a parametric model for a d 33-based cantilever. The analysis revealed that the most significant parameters influencing the resonant frequency are the supporting layer thickness, piezoelectric layer thickness, and cantilever length. On the other hand, the most important factors affecting the charge output arethe piezoelectric thickness and the interdigitated electrode dimensions. The accuracy of the developed model was confirmed and showed less than 1% estimation error compared with a commercial simulation package. To estimate the power delivered to a load, the electric current output from the piezoelectric generator was calculated. A circuit model was built and used to estimate the power delivered to a load, which compared favorably to experimentally published power data on actual cantilevers of similar dimensions. © 2011 TMS.

  12. Modeling the power output of piezoelectric energy harvesters

    KAUST Repository

    Al Ahmad, Mahmoud; Alshareef, Husam N.

    2011-01-01

    Design of experiments and multiphysics analyses were used to develop a parametric model for a d 33-based cantilever. The analysis revealed that the most significant parameters influencing the resonant frequency are the supporting layer thickness, piezoelectric layer thickness, and cantilever length. On the other hand, the most important factors affecting the charge output arethe piezoelectric thickness and the interdigitated electrode dimensions. The accuracy of the developed model was confirmed and showed less than 1% estimation error compared with a commercial simulation package. To estimate the power delivered to a load, the electric current output from the piezoelectric generator was calculated. A circuit model was built and used to estimate the power delivered to a load, which compared favorably to experimentally published power data on actual cantilevers of similar dimensions. © 2011 TMS.

  13. Investigation of solar photovoltaic module power output by various models

    International Nuclear Information System (INIS)

    Jakhrani, A.Q.; Othman, A.K.; Rigit, A.R.H.; Baini, R.

    2012-01-01

    This paper aims to investigate the power output of a solar photovoltaic module by various models and to formulate a suitable model for predicting the performance of solar photovoltaic modules. The model was used to correct the configurations of solar photovoltaic systems for sustainable power supply. Different types of models namely the efficiency, power, fill factor and current-voltage characteristic curve models have been reviewed. It was found that the examined models predicted a 40% yield of the rated power in cloudy weather conditions and up to 80% in clear skies. The models performed well in terms of electrical efficiency in cloudy days if the influence of low irradiance were incorporated. Both analytical and numerical methods were employed in the formulation of improved model which gave +- 2% error when compared with the rated power output of solar photovoltaic module. The proposed model is more practical in terms of number of variables used and acceptable performance in humid atmospheres. Therefore, it could be useful for the estimation of power output of the solar photovoltaic systems in Sarawak region. (author)

  14. S-Band AlGaN/GaN Power Amplifier MMIC with over 20 Watt Output Power

    NARCIS (Netherlands)

    Heijningen, M. van; Visser, G.C.; Wuerfl, J.; Vliet, F.E. van

    2008-01-01

    This paper presents the design of an S-band HPA MMIC in AlGaN/GaN CPW technology for radar TR-module application. The trade-offs of using an MMIC solution versus discrete power devices are discussed. The MMIC shows a maximum output power of 38 Watt at 37% Power Added Efficiency at 3.1 GHz. An output

  15. Power output of field-based downhill mountain biking.

    Science.gov (United States)

    Hurst, Howard Thomas; Atkins, Stephen

    2006-10-01

    The purpose of this study was to assess the power output of field-based downhill mountain biking. Seventeen trained male downhill cyclists (age 27.1 +/- 5.1 years) competing nationally performed two timed runs of a measured downhill course. An SRM powermeter was used to simultaneously record power, cadence, and speed. Values were sampled at 1-s intervals. Heart rates were recorded at 5-s intervals using a Polar S710 heart rate monitor. Peak and mean power output were 834 +/- 129 W and 75 +/- 26 W respectively. Mean power accounted for only 9% of peak values. Paradoxically, mean heart rate was 168 +/- 9 beats x min(-1) (89% of age-predicted maximum heart rate). Mean cadence (27 +/- 5 rev x min(-1)) was significantly related to speed (r = 0.51; P biking. The poor relationships between power and run time and between cadence and run time suggest they are not essential pre-requisites to downhill mountain biking performance and indicate the importance of riding dynamics to overall performance.

  16. Airborne Power Ultrasonic Technologies for Intensification of Food and Environmental Processes

    Science.gov (United States)

    Riera, Enrique; Acosta, Víctor M.; Bon, José; Aleixandre, Manuel; Blanco, Alfonso; Andrés, Roque R.; Cardoni, Andrea; Martinez, Ignacio; Herranz, Luís E.; Delgado, Rosario; Gallego-Juárez, Juan A.

    Airborne power ultrasound is a green technology with a great potential for food and environmental applications, among others. This technology aims at producing permanent changes in objects and substances by means of the propagation of high-intensity waves through air and multiphase media. Specifically, the nonlinear effects produced in such media are responsible for the beneficial repercussions of ultrasound in airborne applications. Processing enhancement is achieved through minimizing the impedance mismatch between the ultrasonic radiator source and the medium by the generation of large vibration displacements and the concentration of energy radiation thus overcoming the high acoustic absorption of fluids, and in particular of gases such as air. Within this work the enhancing effects of airborne power ultrasound in various solid/liquid/gas applications including drying of solid and semi-solid substances, and the agglomeration of tiny particles in air cleaning processes are presented. Moreover, the design of new ultrasonic devices capable of generating these effects are described along with practical methods aimed at maintaining a stable performance of the tuned systems at operational powers. Hence, design strategies based on finite element modelling (FEM) and experimental methods consolidated through the years for material and tuned assembly characterizations are highlighted.

  17. Ultrasonic decontamination robot

    International Nuclear Information System (INIS)

    Patenaude, R.S.

    1984-01-01

    An ultrasonic decontamination robot removes radioactive contamination from the internal surface of the inlet and outlet headers, divider plate, tube sheet, and lower portions of tubes of a nuclear power plant steam generator. A programmable microprocessor controller guides the movement of a robotic arm mounted in the header manway. An ultrasonic transducer having a solvent delivery subsystem through which ultrasonic action is achieved is moved by the arm over the surfaces. A solvent recovery suction tube is positioned within the header to remove solvent therefrom while avoiding interference with the main robotic arm. The solvent composition, temperature, pressure, viscosity, and purity are controlled to optimize the ultrasonic scrubbing action. The ultrasonic transducer is controlled at a power density, frequency, and on-off mode cycle such as to optimize scrubbing action within the range of transducer-to-surface distance and solvent layer thickness selected for the particular conditions encountered. Both solvent and transducer control actions are optimized by the programmable microprocessor. (author)

  18. Determinants of mobile phone output power in a multinational study: implications for exposure assessment

    DEFF Research Database (Denmark)

    Vrijheid, M; Madsen, Stine Mann; di Vecchia, Paolo

    2009-01-01

    OBJECTIVES: The output power of a mobile phone is directly related to its radiofrequency (RF) electromagnetic field strength, and may theoretically vary substantially in different networks and phone use circumstances due to power control technologies. To improve indices of RF exposure for epidemi......OBJECTIVES: The output power of a mobile phone is directly related to its radiofrequency (RF) electromagnetic field strength, and may theoretically vary substantially in different networks and phone use circumstances due to power control technologies. To improve indices of RF exposure...... on the average output power and the percentage call time at maximum power for each call. RESULTS: Measurements of over 60,000 phone calls showed that the average output power was approximately 50% of the maximum, and that output power varied by a factor of up to 2 to 3 between study centres and network operators...

  19. Analysis of losses within SMES system for compensating output fluctuation of wind power farm

    Energy Technology Data Exchange (ETDEWEB)

    Park, S. I.; Kim, J. H.; Le, T. D.; Lee, D. H.; Kim, H. M. [Jeju National University, Jeju (Korea, Republic of); Yoon, Y. S. [Dept. of Electrical Engineering, Shin Ansan University, Ansan (Korea, Republic of); Yoon, K. Y. [Dept. of lectrical and Electronic Engineering, Yonsei University, Seoul (Korea, Republic of)

    2014-12-15

    Output fluctuation which is generated in wind power farm can hinder stability of total power system. The electric energy storage (EES) reduces unstable output, and superconducting magnetic energy storage (SMES) of various EESs has the proper performance for output compensation of wind power farm since it charges and discharges large scale power quickly with high efficiency. However, because of the change of current within SMES, the electromagnetic losses occur in the process of output compensation. In this paper, the thermal effect of the losses that occur in SMES system while compensating in wind power farm is analyzed. The output analysis of wind power farm is processed by numerical analysis, and the losses of SMES system is analyzed by 3D finite element analysis (FEA) simulation tool.

  20. Analysis of losses within SMES system for compensating output fluctuation of wind power farm

    International Nuclear Information System (INIS)

    Park, S. I.; Kim, J. H.; Le, T. D.; Lee, D. H.; Kim, H. M.; Yoon, Y. S.; Yoon, K. Y.

    2014-01-01

    Output fluctuation which is generated in wind power farm can hinder stability of total power system. The electric energy storage (EES) reduces unstable output, and superconducting magnetic energy storage (SMES) of various EESs has the proper performance for output compensation of wind power farm since it charges and discharges large scale power quickly with high efficiency. However, because of the change of current within SMES, the electromagnetic losses occur in the process of output compensation. In this paper, the thermal effect of the losses that occur in SMES system while compensating in wind power farm is analyzed. The output analysis of wind power farm is processed by numerical analysis, and the losses of SMES system is analyzed by 3D finite element analysis (FEA) simulation tool.

  1. Basic study on dynamic reactive-power control method with PV output prediction for solar inverter

    Directory of Open Access Journals (Sweden)

    Ryunosuke Miyoshi

    2016-01-01

    Full Text Available To effectively utilize a photovoltaic (PV system, reactive-power control methods for solar inverters have been considered. Among the various methods, the constant-voltage control outputs less reactive power compared with the other methods. We have developed a constant-voltage control to reduce the reactive-power output. However, the developed constant-voltage control still outputs unnecessary reactive power because the control parameter is constant in every waveform of the PV output. To reduce the reactive-power output, we propose a dynamic reactive-power control method with a PV output prediction. In the proposed method, the control parameter is varied according to the properties of the predicted PV waveform. In this study, we performed numerical simulations using a distribution system model, and we confirmed that the proposed method reduces the reactive-power output within the voltage constraint.

  2. Control strategies to optimise power output in heave buoy energy convertors

    International Nuclear Information System (INIS)

    Abu Zarim, M A U A; Sharip, R M

    2013-01-01

    Wave energy converter (WEC) designs are always discussed in order to obtain an optimum design to generate the power from the wave. Output power from wave energy converter can be improved by controlling the oscillation in order to acquire the interaction between the WEC and the incident wave.The purpose of this research is to study the heave buoys in the interest to generate an optimum power output by optimising the phase control and amplitude in order to maximise the active power. In line with the real aims of this study which investigate the theory and function and hence optimise the power generation of heave buoys as renewable energy sources, the condition that influence the heave buoy must be understand in which to propose the control strategies that can be use to control parameters to obtain optimum power output. However, this research is in an early stage, and further analysis and technical development is require

  3. Simulation and Optimization of Contactless Power Transfer System for Rotary Ultrasonic Machining

    Directory of Open Access Journals (Sweden)

    Wang Xinwei

    2016-01-01

    Full Text Available In today’s rotary ultrasonic machining (RUM, the power transfer system is based on a contactless power system (rotary transformer rather than the slip ring that cannot cope with high-speed rotary of the tool. The efficiency of the rotary transformer is vital to the whole rotary ultrasonic machine. This paper focused on simulation of the rotary transformer and enhancing the efficiency of the rotary transformer by optimizing three main factors that influence its efficiency, including the gap between the two ferrite cores, the ratio of length and width of the ferrite core and the thickness of ferrite. The finite element model of rotary transformer was built on Maxwell platform. Simulation and optimization work was based on the finite element model. The optimization results compared with the initial simulation result showed an approximate 18% enhancement in terms of efficiency, from 77.69% to 95.2%.

  4. Modelling and Prediction of Photovoltaic Power Output Using Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Aminmohammad Saberian

    2014-01-01

    Full Text Available This paper presents a solar power modelling method using artificial neural networks (ANNs. Two neural network structures, namely, general regression neural network (GRNN feedforward back propagation (FFBP, have been used to model a photovoltaic panel output power and approximate the generated power. Both neural networks have four inputs and one output. The inputs are maximum temperature, minimum temperature, mean temperature, and irradiance; the output is the power. The data used in this paper started from January 1, 2006, until December 31, 2010. The five years of data were split into two parts: 2006–2008 and 2009-2010; the first part was used for training and the second part was used for testing the neural networks. A mathematical equation is used to estimate the generated power. At the end, both of these networks have shown good modelling performance; however, FFBP has shown a better performance comparing with GRNN.

  5. Uncertainty analysis of power monitoring transit time ultrasonic flow meters

    International Nuclear Information System (INIS)

    Orosz, A.; Miller, D. W.; Christensen, R. N.; Arndt, S.

    2006-01-01

    A general uncertainty analysis is applied to chordal, transit time ultrasonic flow meters that are used in nuclear power plant feedwater loops. This investigation focuses on relationships between the major parameters of the flow measurement. For this study, mass flow rate is divided into three components, profile factor, density, and a form of volumetric flow rate. All system parameters are used to calculate values for these three components. Uncertainty is analyzed using a perturbation method. Sensitivity coefficients for major system parameters are shown, and these coefficients are applicable to a range of ultrasonic flow meters used in similar applications. Also shown is the uncertainty to be expected for density along with its relationship to other system uncertainties. One other conclusion is that pipe diameter sensitivity coefficients may be a function of the calibration technique used. (authors)

  6. Eddy current and ultrasonic fuel channel inspection at Karachi Nuclear Power Plant

    International Nuclear Information System (INIS)

    Mayo, W.R.; Alam, M.M.

    1997-01-01

    In November of 1993 and in-service inspection was performed on eight fuel channels in the Karachi Nuclear Power Plant (KANUPP) reactor. The workscope included ultrasonic and eddy current volumetric examinations, and eddy current measurement of pressure-to calandria tube gap. This paper briefly discusses the planning strategy of the ultrasonic and eddy current examinations, and describes the equipment developed to meet the requirements, followed by details of the actual channel inspection campaign. The presented nondestructive examinations assisted in determining fitness for service of KANUPP reactor channels in general, and confirmed that the problems associated with channel G12 were not generic in nature. (author)

  7. High Power Tm3+-Doped Fiber Lasers Tuned by a Variable Reflective Output Coupler

    Directory of Open Access Journals (Sweden)

    Yulong Tang

    2008-01-01

    Full Text Available Wide wavelength tuning by a variable reflective output coupler is demonstrated in high-power double-clad Tm3+-doped silica fiber lasers diode-pumped at ∼790  nm. Varying the output coupling from 96% to 5%, the laser wavelength is tuned over a range of 106  nm from 1949 to 2055  nm. The output power exceeds 20  W over 90-nm range and the maximum output power is 32  W at 1949  nm for 51-W launched pump power, corresponding to a slope efficiency of ∼70%. Assisted with different fiber lengths, the tuning range is expanded to 240  nm from 1866 to 2107  nm with the output power larger than 10  W.

  8. Degradation evaluation of high temperature pipeline material for power plant using ultrasonic noise analysis

    International Nuclear Information System (INIS)

    Lee, Sang Guk; Chung, Min Hwa; Cho, Yong Sang; Lee, In Cheol

    2001-01-01

    Boiler high-temperature pipelines such as main steam pipe, header and steam drum in fossil power plants are degraded by creep and thermal fatigue damage due to severe operating conditions such as high temperature and high pressure for an extended period time. Conventional measurement techniques for measuring creep damage have such disadvantages as complex preparation and measurement procedures, too many control parameters. And also these techniques have low practicality and applied only to component surfaces with good accessibility. In this paper, artificial degradation test and ultrasonic measurement for their degraded specimens were carried out for the purpose of evaluation for creep and thermal fatigue damage. Absolute measuring method of quantitative ultrasonic measurement for material degradation was established, and long term creep/thermal fatigue degradation tests using life prediction formula were carried out. As a result of ultrasonic tests for crept and thermal fatigued specimens, we conformed that the ultrasonic noise linearly increased in proportion to the increase of degradation.

  9. Investigation of the visible light photocatalytic activity of BiVO4 prepared by sol gel method assisted by ultrasonication.

    Science.gov (United States)

    Deebasree, J P; Maheskumar, V; Vidhya, B

    2018-07-01

    Visible light induced photocatalyst BiVO 4 with monoclinic scheelite structure has been synthesised via sol gel method assisted by ultrasonication. The prepared samples were characterised using X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis diffused reflectance spectroscopy (DRS) techniques. The photocatalytic efficiency was evaluated by decolourisation of MB under visible light irradiation. The effect of ultrasound output power on the properties of BiVO 4 during and after preparation by sol-gel method has been compared with normal agitated sample (As prepared). The power of ultrasonic vibration has been varied and an ideal output power which yields better catalytic efficiency is determined. BiVO 4 sonicated with 80 W during preparation 80 W (D) exhibited relatively high surface area, better surface morphology and better catalytic efficiency compared to other samples which were sonicated with 100, 160 and 200 W. The results signify that the photodegradation rate of BiVO 4 80 W (D) sample is high up to 96% in 90 min compared to other samples. Change in morphology leading to better catalytic efficiency was obtained just by exposing the sample to ultrasonic radiation without addition of any surfactant. The recovery test showed that the sample was stable for four consecutive cycles. Using radical test, a reasonable mechanism for photodegradation has been proposed. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Ultrasonic recording and display techniques for the inspection of nuclear power plant

    International Nuclear Information System (INIS)

    Ely, R.W.; Hall, G.D.; Johnson, A.; Pascoe, P.T.

    1985-01-01

    This paper describes four systems: MDU, PURDIE, LAURA and DRUID, under development as ultrasonic recording and display techniques for the inspection of nuclear power plant. The MDU system plots either plan or sectional views of the component under test onto a bistable storage screen. PURDIE is a system based around a video cassette recorder which has been modified to record ultrasonic A-scan waveforms and probe positional information. MDU and PURDIE are portable systems, for use under difficult site conditions. They may be manufactured in quantity to satisfy the demanding inspection programmes of nuclear power stations. LAURA is a desk top replay system for the video cassette tapes produced on site by PURDIE. DRUID is a digital desk top replay/display system incorporating a high resolution colour graphics terminal and therefore offering more flexibility and improved display formats. The systems are compatible with each other and some component units are directly interchangeable between the various systems

  11. Laser fiber cleaving techniques: effects on tip morphology and power output.

    Science.gov (United States)

    Vassantachart, Janna M; Lightfoot, Michelle; Yeo, Alexander; Maldonado, Jonathan; Li, Roger; Alsyouf, Muhannad; Martin, Jacob; Lee, Michael; Olgin, Gaudencio; Baldwin, D Duane

    2015-01-01

    Proper cleaving of reusable laser fibers is needed to maintain optimal functionality. This study quantifies the effect of different cleaving tools on power output of the holmium laser fiber and demonstrates morphologic changes using microscopy. The uncleaved tips of new 272 μm reusable laser fibers were used to obtain baseline power transmission values at 3 W (0.6 J, 5 Hz). Power output for each of four cleaving techniques-11-blade scalpel, scribe pen cleaving tool, diamond cleaving wheel, and suture scissors-was measured in a single-blinded fashion. Dispersion of light from the fibers was compared with manufacturer specifications and rated as "ideal," "acceptable," or "unacceptable" by blinded reviewers. The fiber tips were also imaged using confocal and scanning electron microscopy. Independent samples Kruskal-Wallis test and chi square were used for statistical analysis (αtrend that was highly significant (Ptrend as the power output results (P<0.001). Microscopy showed that the scribe pen produced small defects along the fiber cladding but maintained a smooth, flat core surface. The other cleaving techniques produced defects on both the core and cladding. Cleaving techniques produce a significant effect on the initial power transmitted by reusable laser fibers. The scribe pen cleaving tool produced the most consistent and highest average power output.

  12. Optimization and Analysis of a U-Shaped Linear Piezoelectric Ultrasonic Motor Using Longitudinal Transducers.

    Science.gov (United States)

    Yu, Hongpeng; Quan, Qiquan; Tian, Xinqi; Li, He

    2018-03-07

    A novel U-shaped piezoelectric ultrasonic motor that mainly focused on miniaturization and high power density was proposed, fabricated, and tested in this work. The longitudinal vibrations of the transducers were excited to form the elliptical movements on the driving feet. Finite element method (FEM) was used for design and analysis. The resonance frequencies of the selected vibration modes were tuned to be very close to each other with modal analysis and the movement trajectories of the driving feet were gained with transient simulation. The vibration modes and the mechanical output abilities were tested to evaluate the proposed motor further by a prototype. The maximum output speed was tested to be 416 mm/s, the maximum thrust force was 21 N, and the maximum output power was 5.453 W under frequency of 29.52 kHz and voltage of 100 V rms . The maximum output power density of the prototype reached 7.59 W/kg, which was even greater than a previous similar motor under the exciting voltage of 200 V rms . The proposed motor showed great potential for linear driving of large thrust force and high power density.

  13. Modal analysis and nonlinear characterization of an airborne power ultrasonic transducer with rectangular plate radiator.

    Science.gov (United States)

    Andrés, R R; Acosta, V M; Lucas, M; Riera, E

    2018-01-01

    Some industrial processes like particle agglomeration or food dehydration among others can be enhanced by the use of power ultrasonic technologies. These technologies are based on an airborne power ultrasonic transducer (APUT) constituted by a pre-stressed Langevin-type transducer, a mechanical amplifier and an extensive plate radiator. In order to produce the desired effects in industrial processing, the transducer has to vibrate in an extensional mode driving an extensive radiator in the desired flexural mode with high amplitude displacements. Due to the generation of these high amplitude displacements in the radiator surfaces, non-linear effects like frequency shifts, hysteresis or modal interactions, among others, may be produced in the transducer behavior. When any nonlinear effect appears, when applying power, the stability and efficiency of this ultrasonic technology decreases, and the transducer may be damaged depending on the excitation power level and the nature of the nonlinearity. In this paper, an APUT with flat rectangular radiator is presented, as the active part of an innovative system with stepped reflectors. The nonlinear behavior of the APUT has been characterized numerically and experimentally in case of the modal analysis and experimentally in the case of dynamic analysis. According to the results obtained after the experiments, no modal interactions are expected, nor do other nonlinear effects. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Development of Compact Ozonizer with High Ozone Output by Pulsed Power

    Science.gov (United States)

    Tanaka, Fumiaki; Ueda, Satoru; Kouno, Kanako; Sakugawa, Takashi; Akiyama, Hidenori; Kinoshita, Youhei

    Conventional ozonizer with a high ozone output using silent or surface discharges needs a cooling system and a dielectric barrier, and therefore becomes a large machine. A compact ozonizer without the cooling system and the dielectric barrier has been developed by using a pulsed power generated discharge. The wire to plane electrodes made of metal have been used. However, the ozone output was low. Here, a compact and high repetition rate pulsed power generator is used as an electric source of a compact ozonizer. The ozone output of 6.1 g/h and the ozone yield of 86 g/kWh are achieved at 500 pulses per second, input average power of 280 W and an air flow rate of 20 L/min.

  15. A study on electric power management for power producer-suppliers utilizing output of megawatt-solar power plants

    Directory of Open Access Journals (Sweden)

    Hirotaka Takano

    2016-01-01

    Full Text Available The growth in penetration of photovoltaic generation units (PVs has brought new power management ideas, which achieve more profitable operation, to Power Producer-Suppliers (PPSs. The expected profit for the PPSs will improve if they appropriately operate their controllable generators and sell the generated electricity to contracted customers and Power Exchanges together with the output of Megawatt-Solar Power Plants (MSPPs. Moreover, we can expect that the profitable cooperation between the PPSs and the MSPPs decreases difficulties in the supply-demand balancing operation for the main power grids. However, it is necessary that the PPSs treat the uncertainty in output prediction of PVs carefully. This is because there is a risk for them to pay a heavy imbalance penalty. This paper presents a problem framework and its solution to make the optimal power management plan for the PPSs in consideration with the electricity procurement from the MSPPs. The validity of the authors’ proposal is verified through numerical simulations and discussions of their results.

  16. Technique for enhancing the power output of an electrostatic generator employing parametric resonance

    Science.gov (United States)

    Post, Richard F.

    2016-02-23

    A circuit-based technique enhances the power output of electrostatic generators employing an array of axially oriented rods or tubes or azimuthal corrugated metal surfaces for their electrodes. During generator operation, the peak voltage across the electrodes occurs at an azimuthal position that is intermediate between the position of minimum gap and maximum gap. If this position is also close to the azimuthal angle where the rate of change of capacity is a maximum, then the highest rf power output possible for a given maximum allowable voltage at the minimum gap can be attained. This rf power output is then coupled to the generator load through a coupling condenser that prevents suppression of the dc charging potential by conduction through the load. Optimized circuit values produce phase shifts in the rf output voltage that allow higher power output to occur at the same voltage limit at the minimum gap position.

  17. Optimal resonance configuration for ultrasonic wireless power transmission to millimeter-sized biomedical implants.

    Science.gov (United States)

    Miao Meng; Kiani, Mehdi

    2016-08-01

    In order to achieve efficient wireless power transmission (WPT) to biomedical implants with millimeter (mm) dimensions, ultrasonic WPT links have recently been proposed. Operating both transmitter (Tx) and receiver (Rx) ultrasonic transducers at their resonance frequency (fr) is key in improving power transmission efficiency (PTE). In this paper, different resonance configurations for Tx and Rx transducers, including series and parallel resonance, have been studied to help the designers of ultrasonic WPT links to choose the optimal resonance configuration for Tx and Rx that maximizes PTE. The geometries for disk-shaped transducers of four different sets of links, operating at series-series, series-parallel, parallel-series, and parallel-parallel resonance configurations in Tx and Rx, have been found through finite-element method (FEM) simulation tools for operation at fr of 1.4 MHz. Our simulation results suggest that operating the Tx transducer with parallel resonance increases PTE, while the resonance configuration of the mm-sized Rx transducer highly depends on the load resistance, Rl. For applications that involve large Rl in the order of tens of kΩ, a parallel resonance for a mm-sized Rx leads to higher PTE, while series resonance is preferred for Rl in the order of several kΩ and below.

  18. Nonlinear Characterization of Half and Full Wavelength Power Ultrasonic Devices

    Science.gov (United States)

    Mathieson, Andrew; Cerisola, Niccolò; Cardoni, Andrea

    It is well known that power ultrasonic devices whilst driven under elevated excitation levels exhibit nonlinear behaviors. If no attempt is made to understand and subsequently control these behaviors, these devices can exhibit poor performance or even suffer premature failure. This paper presents an experimental method for the dynamic characterization of a commercial ultrasonic transducer for bone cutting applications (Piezosurgery® Device) operated together with a variety of rod horns that are tuned to operate in a longitudinal mode of vibration. Near resonance responses, excited via a burst sine sweep method were used to identify nonlinear responses exhibited by the devices, while experimental modal analysis was performed to identify the modal parameters of the longitudinal modes of vibration of the assemblies between 0-80 kHz. This study tries to provide an understanding of the effects that geometry and material choices may have on the nonlinear behavior of a tuned device.

  19. Ultrasonic Inspection of Cracks in Stud Bolts of Reactor Vessels in Nuclear Power Plants by Signal Processing of Differential Operation

    International Nuclear Information System (INIS)

    Choi, Sang Woo; Lee, Joon Hyun; Oh, Won Deok

    2005-01-01

    The stud bolt is one of crucial parts for safe operation of reactor vessels in nuclear power plants, Crack initiation and propagation were reported in stud bolts that arc used for closure of reactor vessel and head, Stud bolts are inspected by ultrasonic technique during overhaul periodically for the prevention of stud bolt failure which could induce radioactive leakage from nuclear reactor, In conventional ultrasonic testing for inspection of stud bolts, cracks are detected by using shadow effect It takes too much time to inspect stud bolts by using conventional ultrasonic technique. In addition, there were numerous spurious signals reflected from every oblique surfaces of thread, In this study, the signal processing technique for enhancing conventional ultrasonic technique was introduced for inspecting stud bolts. The signal processing technique provides removing spurious signal reflected from every oblique surfaces of thread and enhances detectability of defects. Detectability for small crack was enhanced by using this signal processing in ultrasonic inspection of stud bolts in Nuclear Power Plants

  20. Uncertainties in predicting solar panel power output

    Science.gov (United States)

    Anspaugh, B.

    1974-01-01

    The problem of calculating solar panel power output at launch and during a space mission is considered. The major sources of uncertainty and error in predicting the post launch electrical performance of the panel are considered. A general discussion of error analysis is given. Examples of uncertainty calculations are included. A general method of calculating the effect on the panel of various degrading environments is presented, with references supplied for specific methods. A technique for sizing a solar panel for a required mission power profile is developed.

  1. Design and Optimization of Ultrasonic Wireless Power Transmission Links for Millimeter-Sized Biomedical Implants.

    Science.gov (United States)

    Meng, Miao; Kiani, Mehdi

    2017-02-01

    Ultrasound has been recently proposed as an alternative modality for efficient wireless power transmission (WPT) to biomedical implants with millimeter (mm) dimensions. This paper presents the theory and design methodology of ultrasonic WPT links that involve mm-sized receivers (Rx). For given load (R L ) and powering distance (d), the optimal geometries of transmitter (Tx) and Rx ultrasonic transducers, including their diameter and thickness, as well as the optimal operation frequency (f c ) are found through a recursive design procedure to maximize the power transmission efficiency (PTE). First, a range of realistic f c s is found based on the Rx thickness constrain. For a chosen f c within the range, the diameter and thickness of the Rx transducer are then swept together to maximize PTE. Then, the diameter and thickness of the Tx transducer are optimized to maximize PTE. Finally, this procedure is repeated for different f c s to find the optimal f c and its corresponding transducer geometries that maximize PTE. A design example of ultrasonic link has been presented and optimized for WPT to a 1 mm 3 implant, including a disk-shaped piezoelectric transducer on a silicon die. In simulations, a PTE of 2.11% at f c of 1.8 MHz was achieved for R L of 2.5 [Formula: see text] at [Formula: see text]. In order to validate our simulations, an ultrasonic link was optimized for a 1 mm 3 piezoelectric transducer mounted on a printed circuit board (PCB), which led to simulated and measured PTEs of 0.65% and 0.66% at f c of 1.1 MHz for R L of 2.5 [Formula: see text] at [Formula: see text], respectively.

  2. Investigation on the integral output power model of a large-scale wind farm

    Institute of Scientific and Technical Information of China (English)

    BAO Nengsheng; MA Xiuqian; NI Weidou

    2007-01-01

    The integral output power model of a large-scale wind farm is needed when estimating the wind farm's output over a period of time in the future.The actual wind speed power model and calculation method of a wind farm made up of many wind turbine units are discussed.After analyzing the incoming wind flow characteristics and their energy distributions,and after considering the multi-effects among the wind turbine units and certain assumptions,the incoming wind flow model of multi-units is built.The calculation algorithms and steps of the integral output power model of a large-scale wind farm are provided.Finally,an actual power output of the wind farm is calculated and analyzed by using the practical measurement wind speed data.The characteristics of a large-scale wind farm are also discussed.

  3. Computer simulation of ultrasonic waves in solids

    International Nuclear Information System (INIS)

    Thibault, G.A.; Chaplin, K.

    1992-01-01

    A computer model that simulates the propagation of ultrasonic waves has been developed at AECL Research, Chalk River Laboratories. This program is called EWE, short for Elastic Wave Equations, the mathematics governing the propagation of ultrasonic waves. This report contains a brief summary of the use of ultrasonic waves in non-destructive testing techniques, a discussion of the EWE simulation code explaining the implementation of the equations and the types of output received from the model, and an example simulation showing the abilities of the model. (author). 2 refs., 2 figs

  4. Development and evaluation of a novel low power, high frequency piezoelectric-based ultrasonic reactor for intensifying the transesterification reaction

    Directory of Open Access Journals (Sweden)

    Mortaza Aghbashlo

    2016-12-01

    Full Text Available In this study, a novel low power, high frequency piezoelectric-based ultrasonic reactor was developed and evaluated for intensifying the transesterification process. The reactor was equipped with an automatic temperature control system, a heating element, a precise temperature sensor, and a piezoelectric-based ultrasonic module. The conversion efficiency and specific energy consumption of the reactor were examined under different operational conditions, i.e., reactor temperature (40‒60 °C, ultrasonication time (6‒10 min, and alcohol/oil molar ratio (4:1‒8:1. Transesterification of waste cooking oil (WCO was performed in the presence of a base-catalyst (potassium hydroxide using methanol. According to the obtained results, alcohol/oil molar ratio of 6:1, ultrasonication time of 10 min, and reactor temperature of 60 °C were found as the best operational conditions. Under these conditions, the reactor converted WCO to biodiesel with a conversion efficiency of 97.12%, meeting the ASTM standard satisfactorily, while the lowest specific energy consumption of 378 kJ/kg was also recorded. It should be noted that the highest conversion efficiency of 99.3 %, achieved at reactor temperature of 60 °C, ultrasonication time of 10 min, and alcohol/oil molar ratio of 8:1, was not favorable as the associated specific energy consumption was higher at 395 kJ/kg. Overall, the low power, high frequency piezoelectric-based ultrasonic module could be regarded as an efficient and reliable technology for intensifying the transesterification process in terms of energy consumption, conversion efficiency, and processing time, in comparison with high power, low frequency ultrasonic system reported previously. Finally, this technology could also be considered for designing, developing, and retrofitting chemical reactors being employed for non-biofuel applications as well.

  5. Ultrasonic Phased Array Techniques for Detection of Flaws of Stud Bolts in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Lee, Joon Hyun; Choi, Sang Woo

    2006-01-01

    The reactor vessel body and closure head are fastened with the stud bolt that is one of crucial parts for safety of the reactor vessels in nuclear power plants. It is reported that the stud bolt is often experienced by fatigue cracks initiated at threads. Stud bolts are inspected by the ultrasonic technique during the overhaul periodically for the prevention of failure which leads to radioactive leakage from the nuclear reactor. The conventional ultrasonic inspection for stud bolts was mainly conducted by reflected echo method based on shadow effect. However, in this technique, there were numerous spurious signals reflected from every oblique surfaces of the thread. In this study, ultrasonic phased array technique was applied to investigate detectability of flaws in stud bolts and characteristics of ultrasonic images corresponding to different scanning methods, that is, sector and linear scan. For this purpose, simplified stud bolt specimens with artificial defects of various depths were prepared

  6. Effects of high power ultrasonic vibration on temperature distribution of workpiece in dry creep feed up grinding.

    Science.gov (United States)

    Paknejad, Masih; Abdullah, Amir; Azarhoushang, Bahman

    2017-11-01

    Temperature history and distribution of steel workpiece (X20Cr13) was measured by a high tech infrared camera under ultrasonic assisted dry creep feed up grinding. For this purpose, a special experimental setup was designed and fabricated to vibrate only workpiece along two directions by a high power ultrasonic transducer. In this study, ultrasonic effects with respect to grinding parameters including depth of cut (a e ), feed speed (v w ), and cutting speed (v s ) has been investigated. The results indicate that the ultrasonic vibration has considerable effect on reduction of temperature, depth of thermal damage of workpiece and width of temperature contours. Maximum temperature reduction of 25.91% was reported at condition of v s =15m/s, v w =500mm/min, a e =0.4mm in the presence of ultrasonic vibration. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Power-Combined GaN Amplifier with 2.28-W Output Power at 87 GHz

    Science.gov (United States)

    Fung, King Man; Ward, John; Chattopadhyay, Goutam; Lin, Robert H.; Samoska, Lorene A.; Kangaslahti, Pekka P.; Mehdi, Imran; Lambrigtsen, Bjorn H.; Goldsmith, Paul F.; Soria, Mary M.; hide

    2011-01-01

    Future remote sensing instruments will require focal plane spectrometer arrays with higher resolution at high frequencies. One of the major components of spectrometers are the local oscillator (LO) signal sources that are used to drive mixers to down-convert received radio-frequency (RF) signals to intermediate frequencies (IFs) for analysis. By advancing LO technology through increasing output power and efficiency, and reducing component size, these advances will improve performance and simplify architecture of spectrometer array systems. W-band power amplifiers (PAs) are an essential element of current frequency-multiplied submillimeter-wave LO signal sources. This work utilizes GaN monolithic millimeter-wave integrated circuit (MMIC) PAs developed from a new HRL Laboratories LLC 0.15- m gate length GaN semiconductor transistor. By additionally waveguide power combining PA MMIC modules, the researchers here target the highest output power performance and efficiency in the smallest volume achievable for W-band.

  8. Isolation and characterization of cellulose nanofibers from culinary banana peel using high-intensity ultrasonication combined with chemical treatment.

    Science.gov (United States)

    Khawas, Prerna; Deka, Sankar C

    2016-02-10

    In the present study, culinary banana peel was explored as a source of raw material for production of cellulose nanofibers (CNFs). For isolation of CNFs, first the peel flour was subjected to different chemical treatments to eliminate non-cellulosic compounds. The obtained chemically treated cellulose fibers were then mechanically tailored and separated into nanofibers using high-intensity ultrasonication at different output power ranging from 0 to 1000 W. The presences of nanofibers in all samples were confirmed by TEM. Increasing output power of ultrasonication reduced size of CNFs and generated more thinner and needle-like structure. SEM, FT-IR and XRD results indicated chemical treatment employed was effective in removing compounds other than cellulose fibers. Thermal analyses evinced the developed CNFs enhanced thermal properties which serve the purpose as an effective reinforcing material to be used as bionanocomposites. Hence, the production of CNFs from this underutilized agro-waste has potential application in commercial field that can add high value to culinary banana. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Maximum Power Output of Quantum Heat Engine with Energy Bath

    Directory of Open Access Journals (Sweden)

    Shengnan Liu

    2016-05-01

    Full Text Available The difference between quantum isoenergetic process and quantum isothermal process comes from the violation of the law of equipartition of energy in the quantum regime. To reveal an important physical meaning of this fact, here we study a special type of quantum heat engine consisting of three processes: isoenergetic, isothermal and adiabatic processes. Therefore, this engine works between the energy and heat baths. Combining two engines of this kind, it is possible to realize the quantum Carnot engine. Furthermore, considering finite velocity of change of the potential shape, here an infinite square well with moving walls, the power output of the engine is discussed. It is found that the efficiency and power output are both closely dependent on the initial and final states of the quantum isothermal process. The performance of the engine cycle is shown to be optimized by control of the occupation probability of the ground state, which is determined by the temperature and the potential width. The relation between the efficiency and power output is also discussed.

  10. Lithium niobate ultrasonic transducer design for Enhanced Oil Recovery.

    Science.gov (United States)

    Wang, Zhenjun; Xu, Yuanming; Gu, Yuting

    2015-11-01

    Due to the strong piezoelectric effect possessed by lithium niobate, a new idea that uses lithium niobate to design high-power ultrasonic transducer for Enhanced Oil Recovery technology is proposed. The purpose of this paper is to lay the foundation for the further research and development of high-power ultrasonic oil production technique. The main contents of this paper are as follows: firstly, structure design technique and application of a new high-power ultrasonic transducer are introduced; secondly, the experiment for reducing the viscosity of super heavy oil by this transducer is done, the optimum ultrasonic parameters for reducing the viscosity of super heavy oil are given. Experimental results show that heavy large molecules in super heavy oil can be cracked into light hydrocarbon substances under strong cavitation effect caused by high-intensity ultrasonic wave. Experiment proves that it is indeed feasible to design high-power ultrasonic transducer for ultrasonic oil production technology using lithium niobate. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Procedure Development and Qualification of the Phased Array Ultrasonic Testing for the Nuclear Power Plant Piping Weld

    International Nuclear Information System (INIS)

    Yoon, Byung Sik; Yang, Seung Han; Kim, Yong Sik; Lee, Hee Jong

    2010-01-01

    The manual ultrasonic examination for the nuclear power plant piping welds has been demonstrated by using KPD(Korean Performance Demonstration) generic procedure. For automated ultrasonic examination, there is no generic procedure and it should be qualified by using applicable automated equipment. Until now, most of qualified procedures used pulse-echo technique and there is no qualified procedure using phased array technique. In this study, data acquisition and analysis software were developed and phased-array transducer and wedge were designed to implement phased array technique for nuclear power plant in-service inspection. The developed procedure are qualified for performance demonstration for the flaw detection, length sizing and depth sizing. The qualified procedure will be applied for the field examination in the nuclear power plant piping weld inspection

  12. Power output and efficiency of a thermoelectric generator under temperature control

    International Nuclear Information System (INIS)

    Chen, Wei-Hsin; Wu, Po-Hua; Wang, Xiao-Dong; Lin, Yu-Li

    2016-01-01

    Highlights: • Power output and efficiency of a thermoelectric generator (TEG) is studied. • Temperatures at the module’s surfaces are approximated by sinusoidal functions. • Mean output power and efficiency are enhanced by the temperature oscillation. • The maximum mean efficiency of the TEG in this study is 8.45%. • The phase angle of 180° is a feasible operation for maximizing the performance. - Abstract: Operation control is an effective way to improve the output power of thermoelectric generators (TEGs). The present study is intended to numerically investigate the power output and efficiency of a TEG and find the operating conditions for maximizing its performance. The temperature distributions at the hot side and cold side surfaces of the TEG are approximated by sinusoidal functions. The influences of the temperature amplitudes at the hot side surface and the cold side surface, the phase angle, and the figure-of-merit (ZT) on the performance of the TEG are analyzed. The predictions indicate that the mean output power and efficiency of the TEG are significantly enhanced by the temperature oscillation, whereas the mean absorbed heat by the TEG is slightly influenced. An increase in the temperature amplitude of the hot side surface and the phase angle can effectively improve the performance. For the phase angle of 0°, a smaller temperature amplitude at the cold side surface renders the better performance compared to that with a larger amplitude. When the ZT value increases from 0.736 to 1.8, the mean efficiency at the phase angle of 180° is amplified by a factor of 1.72, and the maximum mean efficiency is 8.45%. In summary, a larger temperature amplitude at the hot side surface with the phase angle of 180° is a feasible operation for maximizing the performance.

  13. Design and optimization of G-band extended interaction klystron with high output power

    Science.gov (United States)

    Li, Renjie; Ruan, Cunjun; Zhang, Huafeng

    2018-03-01

    A ladder-type Extended Interaction Klystron (EIK) with unequal-length slots in the G-band is proposed and designed. The key parameters of resonance cavities working in the π mode are obtained based on the theoretical analysis and 3D simulation. The influence of the device fabrication tolerance on the high-frequency performance is analyzed in detail, and it is found that at least 5 μm of machining precision is required. Thus, the dynamic tuning is required to compensate for the frequency shift and increase the bandwidth. The input and output coupling hole dimensions are carefully designed to achieve high output power along with a broad bandwidth. The effect of surface roughness of the metallic material on the output power has been investigated, and it is proposed that lower surface roughness leads to higher output power. The focusing magnetic field is also optimized to 0.75 T in order to maintain the beam transportation and achieve high output power. With 16.5 kV operating voltage and 0.30 A beam current, the output power of 360 W, the efficiency of 7.27%, the gain of 38.6 dB, and the 3 dB bandwidth of 500 MHz are predicted. The output properties of the EIK show great stability with the effective suppression of oscillation and mode competition. Moreover, small-signal theory analysis and 1D code AJDISK calculations are carried out to verify the results of 3D PIC simulations. A close agreement among the three methods proves the relative validity and the reliability of the designed EIK. Thus, it is indicated that the EIK with unequal-length slots has potential for power improvement and bandwidth extension.

  14. Design and optimization of a modal- independent linear ultrasonic motor.

    Science.gov (United States)

    Zhou, Shengli; Yao, Zhiyuan

    2014-03-01

    To simplify the design of the linear ultrasonic motor (LUSM) and improve its output performance, a method of modal decoupling for LUSMs is proposed in this paper. The specific embodiment of this method is decoupling of the traditional LUSM stator's complex vibration into two simple vibrations, with each vibration implemented by one vibrator. Because the two vibrators are designed independently, their frequencies can be tuned independently and frequency consistency is easy to achieve. Thus, the method can simplify the design of the LUSM. Based on this method, a prototype modal- independent LUSM is designed and fabricated. The motor reaches its maximum thrust force of 47 N, maximum unloaded speed of 0.43 m/s, and maximum power of 7.85 W at applied voltage of 200 Vpp. The motor's structure is then optimized by controlling the difference between the two vibrators' resonance frequencies to reach larger output speed, thrust, and power. The optimized results show that when the frequency difference is 73 Hz, the output force, speed, and power reach their maximum values. At the input voltage of 200 Vpp, the motor reaches its maximum thrust force of 64.2 N, maximum unloaded speed of 0.76 m/s, maximum power of 17.4 W, maximum thrust-weight ratio of 23.7, and maximum efficiency of 39.6%.

  15. Regulation of the output power at the resonant converter

    Energy Technology Data Exchange (ETDEWEB)

    Stefanov, Goce G.; Sarac, Vasilija J. [University Goce Delecev-Stip, Faculty of Electrical Engineering, Radovis (Macedonia, The Former Yugoslav Republic of); Karadzinov, Ljupco V., E-mail: goce.stefanov@ugd.edu.mk [University Kiril and Methodyus-Skopje, FEIT Skopje(Macedonia, The Former Yugoslav Republic of)

    2011-07-01

    In this paper a method for regulating an alternating current voltage source with pair of IGBT transistor’s modules, in a full bridge configuration with series resonant converter is given. With the developed method a solution is obtained which can regulate the phase difference between output voltage and current through the inductor, in order to maintain maximum output power. Control electronic via feedback signals regulates the energy transfer to the tank by changing the pulse width of signals which are used as inputs to the gates of the IGBTs. By increasing or decreasing the pulse width transmitted to the various gates of the IGBT the energy transfer to the tank is increased or decreased . PowerSim simulations program is used for development of controlling methodology. Developed method is practically implemented in a prototype of the device for phase control of resonant converter with variable the resonant load. Key words: pulse width method, phase regulation , power converter.

  16. Brushless power generating system having reduced conducted emissions in output power

    International Nuclear Information System (INIS)

    Walton, D.N.; Dolan, C.F.; Shah, M.J.

    1991-01-01

    This patent describes a brushless electrical power generating system. It comprises an exciter for producing alternating current from an exciter rotor; a rectifier mounted for rotation with the rotor for producing a rectified control current from the alternating current; a common mode inductor, coupled to the rectifier, for cancelling common mode noise components within the rectified control current; and a main generator, having a rotating field winding mounted on a main generator rotor excited by the control current and producing an alternating current power output from a stator

  17. Sonochemical analysis of the output of ultrasonic dental descalers

    OpenAIRE

    King, David

    2010-01-01

    Ultrasonic descalers are used in dentistry to remove calculus and other contaminants from teeth. One mechanism which may assist in the cleaning is cavitation generated in cooling water around the descaler. The spatial distribution of cavitation around three designs of descaler tips and under three load conditions has been observed using sonochemiluminescence from a luminol solution and compared with the vibratory motion of the tips in a water bath, characterised by scanning laser vibrometry. ...

  18. Dynamic Modeling and Very Short-term Prediction of Wind Power Output Using Box-Cox Transformation

    Science.gov (United States)

    Urata, Kengo; Inoue, Masaki; Murayama, Dai; Adachi, Shuichi

    2016-09-01

    We propose a statistical modeling method of wind power output for very short-term prediction. The modeling method with a nonlinear model has cascade structure composed of two parts. One is a linear dynamic part that is driven by a Gaussian white noise and described by an autoregressive model. The other is a nonlinear static part that is driven by the output of the linear part. This nonlinear part is designed for output distribution matching: we shape the distribution of the model output to match with that of the wind power output. The constructed model is utilized for one-step ahead prediction of the wind power output. Furthermore, we study the relation between the prediction accuracy and the prediction horizon.

  19. Using machine learning to predict wind turbine power output

    International Nuclear Information System (INIS)

    Clifton, A; Kilcher, L; Lundquist, J K; Fleming, P

    2013-01-01

    Wind turbine power output is known to be a strong function of wind speed, but is also affected by turbulence and shear. In this work, new aerostructural simulations of a generic 1.5 MW turbine are used to rank atmospheric influences on power output. Most significant is the hub height wind speed, followed by hub height turbulence intensity and then wind speed shear across the rotor disk. These simulation data are used to train regression trees that predict the turbine response for any combination of wind speed, turbulence intensity, and wind shear that might be expected at a turbine site. For a randomly selected atmospheric condition, the accuracy of the regression tree power predictions is three times higher than that from the traditional power curve methodology. The regression tree method can also be applied to turbine test data and used to predict turbine performance at a new site. No new data are required in comparison to the data that are usually collected for a wind resource assessment. Implementing the method requires turbine manufacturers to create a turbine regression tree model from test site data. Such an approach could significantly reduce bias in power predictions that arise because of the different turbulence and shear at the new site, compared to the test site. (letter)

  20. Electroacoustics modeling of piezoelectric welders for ultrasonic additive manufacturing processes

    Science.gov (United States)

    Hehr, Adam; Dapino, Marcelo J.

    2016-04-01

    Ultrasonic additive manufacturing (UAM) is a recent 3D metal printing technology which utilizes ultrasonic vibrations from high power piezoelectric transducers to additively weld similar and dissimilar metal foils. CNC machining is used intermittent of welding to create internal channels, embed temperature sensitive components, sensors, and materials, and for net shaping parts. Structural dynamics of the welder and work piece influence the performance of the welder and part quality. To understand the impact of structural dynamics on UAM, a linear time-invariant model is used to relate system shear force and electric current inputs to the system outputs of welder velocity and voltage. Frequency response measurements are combined with in-situ operating measurements of the welder to identify model parameters and to verify model assumptions. The proposed LTI model can enhance process consistency, performance, and guide the development of improved quality monitoring and control strategies.

  1. Advanced Output Coupling for High Power Gyrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Read, Michael [Calabazas Creek Research, Inc., San Mateo, CA (United States); Ives, Robert Lawrence [Calabazas Creek Research, Inc., San Mateo, CA (United States); Marsden, David [Calabazas Creek Research, Inc., San Mateo, CA (United States); Collins, George [Calabazas Creek Research, Inc., San Mateo, CA (United States); Temkin, Richard [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Guss, William [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Lohr, John [General Atomics, La Jolla, CA (United States); Neilson, Jeffrey [Lexam Research, Redwood City, CA (United States); Bui, Thuc [Calabazas Creek Research, Inc., San Mateo, CA (United States)

    2016-11-28

    The Phase II program developed an internal RF coupler that transforms the whispering gallery RF mode produced in gyrotron cavities to an HE11 waveguide mode propagating in corrugated waveguide. This power is extracted from the vacuum using a broadband, chemical vapor deposited (CVD) diamond, Brewster angle window capable of transmitting more than 1.5 MW CW of RF power over a broad range of frequencies. This coupling system eliminates the Mirror Optical Units now required to externally couple Gaussian output power into corrugated waveguide, significantly reducing system cost and increasing efficiency. The program simulated the performance using a broad range of advanced computer codes to optimize the design. Both a direct coupler and Brewster angle window were built and tested at low and high power. Test results confirmed the performance of both devices and demonstrated they are capable of achieving the required performance for scientific, defense, industrial, and medical applications.

  2. The interdependence of Ca2+ activation, sarcomere length, and power output in the heart.

    Science.gov (United States)

    McDonald, Kerry S

    2011-07-01

    Myocardium generates power to perform external work on the circulation; yet, many questions regarding intermolecular mechanisms regulating power output remain unresolved. Power output equals force × shortening velocity, and some interesting new observations regarding control of these two factors have arisen. While it is well established that sarcomere length tightly controls myocyte force, sarcomere length-tension relationships also appear to be markedly modulated by PKA-mediated phosphorylation of myofibrillar proteins. Concerning loaded shortening, historical models predict independent cross-bridge mechanics; however, it seems that the mechanical state of one population of cross-bridges affects the activity of other cross-bridges by, for example, recruitment of cross-bridges from the non-cycling pool to the cycling force-generating pool during submaximal Ca(2+) activation. This is supported by the findings that Ca(2+) activation levels, myofilament phosphorylation, and sarcomere length are all modulators of loaded shortening and power output independent of their effects on force. This fine tuning of power output probably helps optimize myocardial energetics and to match ventricular supply with peripheral demand; yet, the discernment of the chemo-mechanical signals that modulate loaded shortening needs further clarification since power output may be a key convergent point and feedback regulator of cytoskeleton and cellular signals that control myocyte growth and survival.

  3. Reactor Coolant Temperature Measurement using Ultrasonic Technology

    Energy Technology Data Exchange (ETDEWEB)

    Jung, JaeCheon [KEPCO International Nuclear graduate School, Ulsan (Korea, Republic of); Seo, YongSun; Bechue, Nicholas [Krohne Messtechnik GmbH, Duisburg (Germany)

    2016-10-15

    In NPP, the primary piping temperature is detected by four redundant RTDs (Resistance Temperature Detectors) installed 90 degrees apart on the RCS (Reactor Coolant System) piping circumferentially. Such outputs however, if applied to I and C systems would not give balanced results. The discrepancy can be explained by either thermal stratification or improper arrangement of thermo-wells and RTDs. This phenomenon has become more pronounced in the hot-leg piping than in the cold-leg. Normally, the temperature difference among channels is in the range of 1°F in Korean nuclear power Plants. Consequently, a more accurate pipe average temperate measurement technique is required. Ultrasonic methods can be used to measure average temperatures with relatively higher accuracy than RTDs because the sound wave propagation in the RCS pipe is proportional to the average temperature around pipe area. The inaccuracy of RCS temperature measurement worsens the safety margin for both DNBR and LPD. The possibility of this discrepancy has been reported with thermal stratification effect. Proposed RCS temperature measurement system based on ultrasonic technology offers a countermeasure to cope with thermal stratification effect on hot-leg piping that has been an unresolved issue in NPPs. By introducing ultrasonic technology, the average internal piping temperature can be measured with high accuracy. The inaccuracy can be decreased less than ±1℉ by this method.

  4. Influence of Intra-cell Traffic on the Output Power of Base Station in GSM

    Directory of Open Access Journals (Sweden)

    M. Mileusnic

    2014-06-01

    Full Text Available In this paper we analyze the influence of intracell traffic in a GSM cell on the base station output power. It is proved that intracell traffic increases this power. If offered traffic is small, the increase of output power is equal to the part of intracell traffic. When the offered traffic and, as the result, call loss increase, the increase of output power becomes less. The results of calculation are verified by the computer simulation of traffic process in the GSM cell. The calculation and the simulation consider the uniform distribution of mobile users in the cell, but the conclusions are of a general nature.

  5. Influence of a high vacuum on the precise positioning using an ultrasonic linear motor.

    Science.gov (United States)

    Kim, Wan-Soo; Lee, Dong-Jin; Lee, Sun-Kyu

    2011-01-01

    This paper presents an investigation of the ultrasonic linear motor stage for use in a high vacuum environment. The slider table is driven by the hybrid bolt-clamped Langevin-type ultrasonic linear motor, which is excited with its different modes of natural frequencies in both lateral and longitudinal directions. In general, the friction behavior in a vacuum environment becomes different from that in an environment of atmospheric pressure and this difference significantly affects the performance of the ultrasonic linear motor. In this paper, to consistently provide stable and high power of output in a high vacuum, frequency matching was conducted. Moreover, to achieve the fine control performance in the vacuum environment, a modified nominal characteristic trajectory following control method was adopted. Finally, the stage was operated under high vacuum condition, and the operating performances were investigated compared with that of a conventional PI compensator. As a result, robustness of positioning was accomplished in a high vacuum condition with nanometer-level accuracy.

  6. Influence of a high vacuum on the precise positioning using an ultrasonic linear motor

    International Nuclear Information System (INIS)

    Kim, Wan-Soo; Lee, Dong-Jin; Lee, Sun-Kyu

    2011-01-01

    This paper presents an investigation of the ultrasonic linear motor stage for use in a high vacuum environment. The slider table is driven by the hybrid bolt-clamped Langevin-type ultrasonic linear motor, which is excited with its different modes of natural frequencies in both lateral and longitudinal directions. In general, the friction behavior in a vacuum environment becomes different from that in an environment of atmospheric pressure and this difference significantly affects the performance of the ultrasonic linear motor. In this paper, to consistently provide stable and high power of output in a high vacuum, frequency matching was conducted. Moreover, to achieve the fine control performance in the vacuum environment, a modified nominal characteristic trajectory following control method was adopted. Finally, the stage was operated under high vacuum condition, and the operating performances were investigated compared with that of a conventional PI compensator. As a result, robustness of positioning was accomplished in a high vacuum condition with nanometer-level accuracy.

  7. A piezoelectric ultrasonic linear micromotor using a slotted stator.

    Science.gov (United States)

    Yun, Cheol-Ho; Watson, Brett; Friend, James; Yeo, Leslie

    2010-08-01

    A novel ultrasonic micro linear motor that uses 1st longitudinal and 2nd bending modes, derived from a bartype stator with a rectangular slot cut through the stator length, has been proposed and designed for end-effect devices of microrobotics and bio-medical applications. The slot structure plays an important role in the motor design, and can be used not only to tune the resonance frequency of the two vibration modes but also to reduce the undesirable longitudinal coupling displacement caused by bending vibration at the end of the stator. By using finite element analysis, the optimal slot dimension to improve the driving tip motion was determined, resulting in the improvement of the motor performance. The trial linear motor, with a weight of 1.6 g, gave a maximum driving velocity of 1.12 m/s and a maximum driving force of 3.4 N. A maximum mechanical output power of 1.1 W was obtained at force of 1.63 N and velocity of 0.68 m/s. The output mechanical power per unit weight was 688 W/kg.

  8. Comparison of cardiac output measurement techniques

    DEFF Research Database (Denmark)

    Espersen, K; Jensen, E W; Rosenborg, D

    1995-01-01

    Simultaneously measured cardiac output obtained by thermodilution (TD), transcutaneous suprasternal ultrasonic Doppler (DOP), CO2-rebreathing (CR) and the direct Fick method (FI) were compared in eleven healthy subjects in a supine position (SU), a sitting position (SI), and during sitting exercise...

  9. Effect of material constants on power output in piezoelectric vibration-based generators.

    Science.gov (United States)

    Takeda, Hiroaki; Mihara, Kensuke; Yoshimura, Tomohiro; Hoshina, Takuya; Tsurumi, Takaaki

    2011-09-01

    A possible power output estimation based on material constants in piezoelectric vibration-based generators is proposed. A modified equivalent circuit model of the generator was built and was validated by the measurement results in the generator fabricated using potassium sodium niobate-based and lead zirconate titanate (PZT) ceramics. Subsequently, generators with the same structure using other PZT-based and bismuth-layered structure ferroelectrics ceramics were fabricated and tested. The power outputs of these generators were expressed as a linear functions of the term composed of electromechanical coupling coefficients k(sys)(2) and mechanical quality factors Q*(m) of the generator. The relationship between device constants (k(sys)(2) and Q*(m)) and material constants (k(31)(2) and Q(m)) was clarified. Estimation of the power output using material constants is demonstrated and the appropriate piezoelectric material for the generator is suggested.

  10. Output power characteristics of the neutral xenon long laser

    Energy Technology Data Exchange (ETDEWEB)

    Linford, G.J. [TRW Space and Electronics Group, Redondo Beach, CA (United States). Space and Technology Div.

    1994-12-31

    Lasers which oscillate within inhomogeneously broadened gain media exhibit spectral hole burning and concomitant reduction in output power compared with equivalent homogeneously-broadened laser gain media. By increasing the cavity length, it may be possible to demonstrate at least a partial transition from an inhomogeneous laser cavity mode spectrum to a homogeneous spectrum. There are a number of high gain laser lines which are inhomogeneously-broadened transitions in electric discharges of neutral xenon. In neutral xenon lasers, as in the cases of many other gas lasers, the inhomogeneous spectral broadening mechanism arises from Doppler shifts, {Delta}{nu}{sub D}, of individual atoms in thermal motion within the electric discharge comprising the laser gain medium. Optical transitions corresponding to these noble gas atoms have natural linewidths, {Delta}{nu}{sub n}{lt}{Delta}{nu}{sub D}. Simulations of the output power characteristics of the xenon laser were carried out as a function of laser cavity parameters, including the cavity length, L. These calculations showed that when the intracavity mode spacing frequency, c/2L{lt}{Delta}{nu}{sub n}, the inhomogeneously broadened xenon mode spectrum converted to a homogeneously broadened oscillation spectrum with an increase in output power. These simulations are compared with experimental results obtained for the long laser oscillation characteristics of the (5d[5/2]{degree}{sub 2}{r_arrow}6p[3/2]{sub 1}) transition corresponding to the strong, high-gain 3.508 {mu} line in xenon.

  11. Maximizing power output from continuous-wave single-frequency fiber amplifiers.

    Science.gov (United States)

    Ward, Benjamin G

    2015-02-15

    This Letter reports on a method of maximizing the power output from highly saturated cladding-pumped continuous-wave single-frequency fiber amplifiers simultaneously, taking into account the stimulated Brillouin scattering and transverse modal instability thresholds. This results in a design figure of merit depending on the fundamental mode overlap with the doping profile, the peak Brillouin gain coefficient, and the peak mode coupling gain coefficient. This figure of merit is then numerically analyzed for three candidate fiber designs including standard, segmented acoustically tailored, and micro-segmented acoustically tailored photonic-crystal fibers. It is found that each of the latter two fibers should enable a 50% higher output power than standard photonic crystal fiber.

  12. A Free-Piston Linear Generator Control Strategy for Improving Output Power

    Directory of Open Access Journals (Sweden)

    Chi Zhang

    2018-01-01

    Full Text Available This paper presents a control strategy to improve the output power for a single-cylinder two-stroke free-piston linear generator (FPLG. The comprehensive simulation model of this FPLG is established and the operation principle is introduced. The factors that affect the output power are analyzed theoretically. The characteristics of the piston motion are studied. Considering the different features of the piston motion respectively in acceleration and deceleration phases, a ladder-like electromagnetic force control strategy is proposed. According to the status of the linear electric machine, the reference profile of the electromagnetic force is divided into four ladder-like stages during one motion cycle. The piston motions, especially the dead center errors, are controlled by regulating the profile of the electromagnetic force. The feasibility and advantage of the proposed control strategy are verified through comparison analyses with two conventional control strategies via MatLab/Simulink. The results state that the proposed control strategy can improve the output power by around 7–10% with the same fuel cycle mass.

  13. Uncertainty estimation of ultrasonic thickness measurement

    International Nuclear Information System (INIS)

    Yassir Yassen, Abdul Razak Daud; Mohammad Pauzi Ismail; Abdul Aziz Jemain

    2009-01-01

    The most important factor that should be taken into consideration when selecting ultrasonic thickness measurement technique is its reliability. Only when the uncertainty of a measurement results is known, it may be judged if the result is adequate for intended purpose. The objective of this study is to model the ultrasonic thickness measurement function, to identify the most contributing input uncertainty components, and to estimate the uncertainty of the ultrasonic thickness measurement results. We assumed that there are five error sources significantly contribute to the final error, these sources are calibration velocity, transit time, zero offset, measurement repeatability and resolution, by applying the propagation of uncertainty law to the model function, a combined uncertainty of the ultrasonic thickness measurement was obtained. In this study the modeling function of ultrasonic thickness measurement was derived. By using this model the estimation of the uncertainty of the final output result was found to be reliable. It was also found that the most contributing input uncertainty components are calibration velocity, transit time linearity and zero offset. (author)

  14. Integrating wind output with bulk power operations and wholesale electricity markets

    International Nuclear Information System (INIS)

    Hirst, E.

    2002-01-01

    Wind farms have three characteristics that complicate their widespread application as an electricity resource: limited control, unpredictability and variability. Therefore the integration of wind output into bulk power electric systems is qualitatively different from that of other types of generators. The electric system operator must move other generators up or down to offset the time-varying wind fluctuations. Such movements raise the costs of fuel and maintenance for these other generators. Not only is wind power different, it is new. The operators of bulk power systems have limited experience in integrating wind output into the larger system. As a consequence, market rules that treat wind fairly - neither subsidizing nor penalizing its operation - have not yet been developed. The lack of data and analytical methods encourages wind advocates and sceptics to rely primarily on their biases and beliefs in suggesting how wind should be integrated into bulk power systems. This project helps fill this data and analysis gap. Specifically, it develops and applies a quantitative method for the integration of a wind resource into a large electric system. The method permits wind to bid its output into a short-term forward market (specifically, an hour-ahead energy market) or to appear in real time and accept only intrahour and hourly imbalance payments for the unscheduled energy it delivers to the system. Finally, the method analyses the short-term (minute-to-minute) variation in wind output to determine the regulation requirement the wind resource imposes on the electrical system. (author)

  15. The effects of training with loads that maximise power output and individualised repetitions vs. traditional power training.

    Directory of Open Access Journals (Sweden)

    J M Sarabia

    Full Text Available It has been suggested that strength training effects (i.e. neural or structural vary, depending on the total repetitions performed and velocity loss in each training set.The aim of this study is to compare the effects of two training programmes (i.e. one with loads that maximise power output and individualised repetitions, and the other following traditional power training.Twenty-five males were divided into three groups (optimum power [OP = 10], traditional training [TT = 9] and control group [CG = 6]. The training load used for OP was individualised using loads that maximised power output (41.7% ± 5.8 of one repetition maximum [1RM] and repetitions at maximum power (4 to 9 repetitions, or 'reps'. Volume (sets x repetitions was the same for both experimental groups, while intensity for TT was that needed to perform only 50% of the maximum number of possible repetitions (i.e. 61.1%-66.6% of 1RM. The training programme ran over 11 weeks (2 sessions per week; 4-5 sets per session; 3-minute rests between sets, with pre-, intermediate and post-tests which included: anthropometry, 1RM, peak power output (PPO with 30%, 40% and 50% of 1RM in the bench press throw, and salivary testosterone (ST and cortisol (SC concentrations. Rate of perceived exertion (RPE and power output were recorded in all sessions.Following the intermediate test, PPO was increased in the OP group for each load (10.9%-13.2%. Following the post-test, both experimental groups had increased 1RM (11.8%-13.8% and PPO for each load (14.1%-19.6%. Significant decreases in PPO were found for the TT group during all sets (4.9%-15.4%, along with significantly higher RPE (37%.OP appears to be a more efficient method of training, with less neuromuscular fatigue and lower RPE.

  16. An Improved Mathematical Model for Computing Power Output of Solar Photovoltaic Modules

    Directory of Open Access Journals (Sweden)

    Abdul Qayoom Jakhrani

    2014-01-01

    Full Text Available It is difficult to determine the input parameters values for equivalent circuit models of photovoltaic modules through analytical methods. Thus, the previous researchers preferred to use numerical methods. Since, the numerical methods are time consuming and need long term time series data which is not available in most developing countries, an improved mathematical model was formulated by combination of analytical and numerical methods to overcome the limitations of existing methods. The values of required model input parameters were computed analytically. The expression for output current of photovoltaic module was determined explicitly by Lambert W function and voltage was determined numerically by Newton-Raphson method. Moreover, the algebraic equations were derived for the shape factor which involves the ideality factor and the series resistance of a single diode photovoltaic module power output model. The formulated model results were validated with rated power output of a photovoltaic module provided by manufacturers using local meteorological data, which gave ±2% error. It was found that the proposed model is more practical in terms of precise estimations of photovoltaic module power output for any required location and number of variables used.

  17. High-power direct diode laser output by spectral beam combining

    Science.gov (United States)

    Tan, Hao; Meng, Huicheng; Ruan, Xu; Du, Weichuan; Wang, Zhao

    2018-03-01

    We demonstrate a spectral beam combining scheme based on multiple mini-bar stacks, which have more diode laser combining elements, to increase the combined diode laser power and realize equal beam quality in both the fast and slow axes. A spectral beam combining diode laser output of 1130 W is achieved with an operating current of 75 A. When a 9.6 X de-magnifying telescope is introduced between the output mirror and the diffraction grating, to restrain cross-talk among diode laser emitters, a 710 W spectral beam combining diode laser output is achieved at the operating current of 70 A, and the beam quality on the fast and slow axes of the combined beam is about 7.5 mm mrad and 7.3 mm mrad respectively. The power reduction is caused by the existence of a couple resonator between the rear facet of the diode laser and the fast axis collimation lens, and it should be eliminated by using diode laser chips with higher front facet transmission efficiency and a fast axis collimation lens with lower residual reflectivity.

  18. Call-related factors influencing output power from mobile phones.

    Science.gov (United States)

    Hillert, Lena; Ahlbom, Anders; Neasham, David; Feychting, Maria; Järup, Lars; Navin, Roshan; Elliott, Paul

    2006-11-01

    Mobile phone use is increasing but there is also concern for adverse health effects. Well-designed prospective studies to assess several health outcomes are required. In designing a study of mobile phone use, it is important to assess which factors need to be considered in classifying the exposure to radiofrequency fields (RF). A pilot study was performed in Sweden and in the UK 2002 to 2003 to test the feasibility of recruiting a cohort of mobile phone users from a random population sample and from mobile phone subscription lists for a prospective study. As one part of this pilot study, different factors were evaluated regarding possible influence on the output power of the phones. By local switch logging, information on calls made from predefined subscriptions or dedicated handsets were obtained and the output power of phones during calls made indoors and outdoors, in moving and stationary mode, and in rural as well in urban areas were compared. In this experiment, calls were either 1, 1.5 or 5 min long. The results showed that high mobile phone output power is more frequent in rural areas whereas the other factors (length of call, moving/stationary, indoor/outdoor) were of less importance. Urban and rural area should be considered in an exposure index for classification of the exposure to RF from mobile phones and may be assessed by first base station during mobile phone calls or, if this information is not available, possibly by using home address as a proxy.

  19. Current status of automated ultrasonic pipe inspection systems - ISI of stainless steel piping systems in BWR power plants

    International Nuclear Information System (INIS)

    Jeong, P.

    1985-01-01

    The field of ultrasonics nondestructive testing is constantly expanding its ability of acquiring data and its speed by implementing a computer into the testing system. The computer made it possible to store massive test data into a compact magnetic hard disk for permanent records. The data outputs are displayed on the color CRT screen, and varieties of image display methods, such as A-scan, B-scan, C-scan, P-scan, or many other 3 dimensional isometric views and the modified display techniques are available to an operator. Various hardcopy machines are now a part of the testing system so that the displayed data outputs can be easily copied and filed for permanent documentation. The faster and more accurate mechanized scanners are gradually being substituted for the conventional manual scanning method which has been a major time consuming part of the testing operation. When all such improvements are combined into an integral unit, a reliable, fully automated ultrasonic testing system can by made. The fully automated ultrasonic testing system is needed not only for fast data acquisition, processing, and reliable data display, but also, even more importantly, for considerable reduction of human intervention, which could be a critical factor under the severely limited field environment. Obviously, in the past several years, tremendous accomplishments have been made in automating the test system, and many such systems are being used in the field. However, most of the existing automated systems are still bulky in size and the displayed data is often difficult to interpret to the field operators. Major effect should, therefore, be directed to size reduction of the system as well as improvement on the system reliability

  20. 915 MHz microwave ablation with high output power in in vivo porcine spleens

    International Nuclear Information System (INIS)

    Gao Yongyan; Wang Yang; Duan Yaqi; Li Chunling; Sun Yuanyuan; Zhang Dakun; Lu Tong; Liang Ping

    2010-01-01

    Objective: The purpose of this study was to evaluate the efficacy of 915 MHz microwave (MW) ablation with high output power in in vivo porcine spleens. Materials and methods: MW ablations were performed in 9 porcine spleens with an internally cooled 915 MHz antenna. Thermocouples were placed at 5, 10, 15, 20 mm away from the antenna to measure temperatures in real-time during MW emission. The energy was applied for 10 min at high output power of 60 W, 70 W or 80 W. Gross specimens were sectioned and measured to determine ablation size. Representative areas were examined by light microscopy and electron microscopy. Coagulation sizes and temperatures were compared among the three power groups. Results: Hematoxylin-eosin staining showed irreversible necrosis in the splenic coagulation area after MW ablation. As the power was increased, long-axis diameter enlarged significantly (p .05). The coagulation size of long-axis and short-axis diameter with 80 W in vivo spleen ablation was 6.43 ± 0.52 and 4.95 ± 0.30 cm, respectively. With the increase of output power, maximum temperatures at 5, 10, 15, 20 mm from the antenna were increased accordingly (p o C respectively. Conclusion: With internally cooled antenna and high output power, 915 MHz MW ablation in the spleen could produce irreversible tissue necrosis of clinical significance. MW ablation may be used as a promising minimally invasive method for the treatment of splenic diseases.

  1. S-Band AlGaN/GaN power amplifier MMIC with over 20 Watt output power

    NARCIS (Netherlands)

    van Heijningen, M; Visser, G.C.; Wurfl, J.; van Vliet, Frank Edward

    2008-01-01

    Abstract This paper presents the design of an S-band HPA MMIC in AlGaN/GaN CPW technology for radar TR-module application. The trade-offs of using an MMIC solution versus discrete power devices are discussed. The MMIC shows a maximum output power of 38 Watt at 37% Power Added Efficiency at 3.1 GHz.

  2. Improving the Output Power Stability of a High Concentration Photovoltaic System with Supercapacitors: A Preliminary Evaluation

    Directory of Open Access Journals (Sweden)

    Yu-Pei Huang

    2015-01-01

    Full Text Available The output power of a high concentration photovoltaic (HCPV system is very sensitive to fluctuating tracking errors and weather patterns. To help compensate this shortcoming, supercapacitors have been successfully incorporated into photovoltaic systems to improve their output power stability. This study examined the output power stability improvement of an HCPV module with a supercapacitor integrated into its circuit. Furthermore, the equivalent model of the experimental circuit is presented and analyzed. Experimental results suggest that integrating a supercapacitor into an HCPV module could improve its output power stability and further extend its acceptance angle. This paper provides preliminary data of the improvement and its evaluation method, which could be utilized for further improvements to an HCPV system.

  3. Maximizing Output Power of a Solar Panel via Combination of Sun Tracking and Maximum Power Point Tracking by Fuzzy Controllers

    Directory of Open Access Journals (Sweden)

    Mohsen Taherbaneh

    2010-01-01

    Full Text Available In applications with low-energy conversion efficiency, maximizing the output power improves the efficiency. The maximum output power of a solar panel depends on the environmental conditions and load profile. In this paper, a method based on simultaneous use of two fuzzy controllers is developed in order to maximize the generated output power of a solar panel in a photovoltaic system: fuzzy-based sun tracking and maximum power point tracking. The sun tracking is performed by changing the solar panel orientation in horizontal and vertical directions by two DC motors properly designed. A DC-DC converter is employed to track the solar panel maximum power point. In addition, the proposed system has the capability of the extraction of solar panel I-V curves. Experimental results present that the proposed fuzzy techniques result in increasing of power delivery from the solar panel, causing a reduction in size, weight, and cost of solar panels in photovoltaic systems.

  4. [Effects of ultrasonic pretreatment on drying characteristics of sewage sludge].

    Science.gov (United States)

    Li, Run-Dong; Yang, Yu-Ting; Li, Yan-Long; Niu, Hui-Chang; Wei, Li-Hong; Sun, Yang; Ke, Xin

    2009-11-01

    The high water content of sewage sludge has engendered many inconveniences to its treatment and disposal. While ultrasonic takes on unique advantages on the sludge drying because of its high ultrasonic power, mighty penetrating capability and the ability of causing cavitations. Thus this research studies the characteristics influences of ultrasonic bring to the sludge drying and effects of the exposure time, ultrasonic generator power, temperatures of ultrasonic and drying temperature on the drying characteristics of dewatered sludge. Results indicate that ultrasonic pretreatment could speed up evaporation of the free water in sludge surface and help to end the drying stage with constant speed. In addition, ultrasonic treatment can effectively improve the sludge drying efficiency which could be more evident with the rise of the ultrasonic power (100-250 W), ultrasonic temperature and drying temperature. If dried under low temperature such as 105 degrees C, sludge will have premium drying characteristics when radiated under ultrasound for a shorter time such as 3 min. In the end, the ultrasonic treatment is expected to be an effective way to the low-cost sludge drying and also be an important reference to the optimization of the sludge drying process because of its effects on the increase of sludge drying efficiency.

  5. Solar Power Station Output Inverter Control Design

    Directory of Open Access Journals (Sweden)

    J. Bauer

    2011-04-01

    Full Text Available The photovoltaic applications spreads in these days fast, therefore they also undergo great development. Because the amount of the energy obtained from the panel depends on the surrounding conditions, as intensity of the sun exposure or the temperature of the solar array, the converter must be connected to the panel output. The Solar system equipped with inverter can supply small loads like notebooks, mobile chargers etc. in the places where the supplying network is not present. Or the system can be used as a generator and it shall deliver energy to the supply network. Each type of the application has different requirements on the converter and its control algorithm. But for all of them the one thing is common – the maximal efficiency. The paper focuses on design and simulation of the low power inverter that acts as output part of the whole converter. In the paper the design of the control algorithm of the inverter for both types of inverter application – for islanding mode and for operation on the supply grid – is discussed. Attention is also paid to the design of the output filter that should reduce negative side effects of the converter on the supply network.

  6. Measuring power output intermittency and unsteady loading in a micro wind farm model

    OpenAIRE

    Bossuyt, Juliaan; Howland, Michael; Meneveau, Charles; Meyers, Johan

    2016-01-01

    In this study porous disc models are used as a turbine model for a wind-tunnel wind farm experiment, allowing the measurement of the power output, thrust force and spatially averaged incoming velocity for every turbine. The model's capabilities for studying the unsteady turbine loading, wind farm power output intermittency and spatio temporal correlations between wind turbines are demonstrated on an aligned wind farm, consisting of 100 wind turbine models.

  7. Transient analysis of the output short-circuit fault of high power and high voltage DC power supply

    International Nuclear Information System (INIS)

    Yang Zhigang; Zhang Jian; Huang Yiyun; Hao Xu; Sun Haozhang; Guo Fei

    2014-01-01

    The transient conditions of output short-circuit fault of high voltage DC power supply was introduced, and the energy of power supply injecting into klystron during the protection process of three-electrode gas switch were analyzed and calculated in detail when klystron load happening electrode arc faults. The results of calculation and simulation are consistent with the results of the experiment. When the output short-circuit fault of high voltage power supply occurs, switch can be shut off in the microsecond, and the short circuit current can be controlled in 200 A. It has verified the rapidity and reliability of the three-electrode gas switch protection, and it has engineering application value. (authors)

  8. Methodological concerns for determining power output in the jump squat.

    Science.gov (United States)

    Cormie, Prue; Deane, Russell; McBride, Jeffrey M

    2007-05-01

    The purpose of this study was to investigate the validity of power measurement techniques during the jump squat (JS) utilizing various combinations of a force plate and linear position transducer (LPT) devices. Nine men with at least 6 months of prior resistance training experience participated in this acute investigation. One repetition maximums (1RM) in the squat were determined, followed by JS testing under 2 loading conditions (30% of 1RM [JS30] and 90% of 1RM [JS90]). Three different techniques were used simultaneously in data collection: (a) 1 linear position transducer (1-LPT); (b) 1 linear position transducer and a force plate (1-LPT + FP); and (c) 2 linear position transducers and a force place (2-LPT + FP). Vertical velocity-, force-, and power-time curves were calculated for each lift using these methodologies and were compared. Peak force and peak power were overestimated by 1-LPT in both JS30 and JS90 compared with 2-LPT + FP and 1-LPT + FP (p squat varies according to the measurement technique utilized. The 1-LPT methodology is not a valid means of determining power output in the jump squat. Furthermore, the 1-LPT + FP method may not accurately represent power output in free weight movements that involve a significant amount of horizontal motion.

  9. Stochastic Short-term High-resolution Prediction of Solar Irradiance and Photovoltaic Power Output

    Energy Technology Data Exchange (ETDEWEB)

    Melin, Alexander M. [ORNL; Olama, Mohammed M. [ORNL; Dong, Jin [ORNL; Djouadi, Seddik M. [ORNL; Zhang, Yichen [University of Tennessee, Knoxville (UTK), Department of Electrical Engineering and Computer Science

    2017-09-01

    The increased penetration of solar photovoltaic (PV) energy sources into electric grids has increased the need for accurate modeling and prediction of solar irradiance and power production. Existing modeling and prediction techniques focus on long-term low-resolution prediction over minutes to years. This paper examines the stochastic modeling and short-term high-resolution prediction of solar irradiance and PV power output. We propose a stochastic state-space model to characterize the behaviors of solar irradiance and PV power output. This prediction model is suitable for the development of optimal power controllers for PV sources. A filter-based expectation-maximization and Kalman filtering mechanism is employed to estimate the parameters and states in the state-space model. The mechanism results in a finite dimensional filter which only uses the first and second order statistics. The structure of the scheme contributes to a direct prediction of the solar irradiance and PV power output without any linearization process or simplifying assumptions of the signal’s model. This enables the system to accurately predict small as well as large fluctuations of the solar signals. The mechanism is recursive allowing the solar irradiance and PV power to be predicted online from measurements. The mechanism is tested using solar irradiance and PV power measurement data collected locally in our lab.

  10. Somatotype variables related to strength and power output in male basketball players.

    Science.gov (United States)

    Buśko, Krzysztof; Pastuszak, Anna; Lipińska, Monika; Lipińska, Marta; Gryko, Karol

    2017-01-01

    The purpose of this study was to investigate the relationship between somatotype, muscular strength, power output measured in maximal cycle ergometer exercise bouts, and maximal power output and height of rise of the body mass centre (jump height) measured in akimbo counter movement jump (ACMJ), counter movement jump (CMJ) and spike jump (SPJ), in male basketball players. Thirteen male basketball players (second division, age 19.4 ± 0.8 years, body height 192.9 ± 5.6 cm, body mass 88.8 ± 8.6 kg, training experience 9.3 ± 0.8 years) participated in the study. Somatotype was determined using the Heath-Carter method. Maximal joint torques were measured under static conditions. Power output was measured in 2 maximal cycle ergometer exercise bouts, 10 seconds each, with increasing external loads equal to 7.5 and 10.0% of the body weight (BW). All jump trials (ACMJ, CMJ and SPJ) were performed on a force plate. The mean somatotype of basketball players amounted to: 2.8-4.2-3.2. The sum of the joint torques for left and right lower extremities (0.613), trunk (0.631) and all six measured muscle groups (0.647) were significantly correlated (p jump during ACMJ, CMJ and SPJ trials. The power output measured in maximal cycle ergometer exercise bouts with increasing external loads was significantly correlated (p basketball players' anthropometric characteristics can influence their level of performance but it is not a decisive factor.

  11. Operational measurements of stack flow rates in a nuclear power plant with ultrasonic anemometer

    International Nuclear Information System (INIS)

    Voelz, E.; Kirtzel, H.-J.; Ebenhoech, E.

    2003-01-01

    The calculation of the impact of radio nuclides within the surroundings of nuclear power stations requires quantitative measurements of the stack emission. As a standard method, propeller anemometers have been installed inside the stack, but due to the wear and tear of the moving parts in such conventional sensors the servicing and maintenance are costly and may cause restrictions in the operation of the stack. As an alternative to propeller anemometers ultrasonic sensors have been applied which employ no moving parts and are almost free of maintenance. Furthermore, any shifts in internal calibration parameters can be identified by the sensor electronics with on-line plausibility checks. The tests have proven that ultrasonic systems are able to measure adequately and reliably the flow inside the stack. (orig.)

  12. Modulating wind power plant output using different frequency modulation components for damping grid oscillations

    DEFF Research Database (Denmark)

    2017-01-01

    A method, controller, wind power plant, and computer program product are disclosed for operating a wind power plant comprising a plurality of wind turbines, the wind power plant producing a plant power output. The method comprises receiving a modulation request signal indicating a requested...... modulation of the plant power output, the requested modulation specifying a modulation frequency. The method further comprises generating a respective power reference signal for each of at least two wind turbines of the plurality of wind turbines selected to fulfill the requested modulation, Each generated...... power reference signal includes a respective modulation component corresponding to a portion of the requested modulation and having a frequency different than the modulation frequency....

  13. Development of phased-array ultrasonic testing probe

    International Nuclear Information System (INIS)

    Kawanami, Seiichi; Kurokawa, Masaaki; Taniguchi, Masaru; Tada, Yoshihisa

    2001-01-01

    Phased-array ultrasonic testing was developed for nondestructive evaluation of power plants. Phased-array UT scans and focuses an ultrasonic beam to inspect areas difficult to inspect by conventional UT. We developed a highly sensitive piezoelectric composite, and designed optimized phased-array UT probes. We are applying our phased-array UT to different areas of power plants. (author)

  14. The effects of training with loads that maximise power output and individualised repetitions vs. traditional power training

    Science.gov (United States)

    Moya-Ramón, M.; Hernández-Davó, J. L.; Fernandez-Fernandez, J.; Sabido, R.

    2017-01-01

    Background It has been suggested that strength training effects (i.e. neural or structural) vary, depending on the total repetitions performed and velocity loss in each training set. Purpose The aim of this study is to compare the effects of two training programmes (i.e. one with loads that maximise power output and individualised repetitions, and the other following traditional power training). Methods Twenty-five males were divided into three groups (optimum power [OP = 10], traditional training [TT = 9] and control group [CG = 6]). The training load used for OP was individualised using loads that maximised power output (41.7% ± 5.8 of one repetition maximum [1RM]) and repetitions at maximum power (4 to 9 repetitions, or ‘reps’). Volume (sets x repetitions) was the same for both experimental groups, while intensity for TT was that needed to perform only 50% of the maximum number of possible repetitions (i.e. 61.1%–66.6% of 1RM). The training programme ran over 11 weeks (2 sessions per week; 4–5 sets per session; 3-minute rests between sets), with pre-, intermediate and post-tests which included: anthropometry, 1RM, peak power output (PPO) with 30%, 40% and 50% of 1RM in the bench press throw, and salivary testosterone (ST) and cortisol (SC) concentrations. Rate of perceived exertion (RPE) and power output were recorded in all sessions. Results Following the intermediate test, PPO was increased in the OP group for each load (10.9%–13.2%). Following the post-test, both experimental groups had increased 1RM (11.8%–13.8%) and PPO for each load (14.1%–19.6%). Significant decreases in PPO were found for the TT group during all sets (4.9%–15.4%), along with significantly higher RPE (37%). Conclusion OP appears to be a more efficient method of training, with less neuromuscular fatigue and lower RPE. PMID:29053725

  15. A combined compensation method for the output voltage of an insulated core transformer power supply

    Energy Technology Data Exchange (ETDEWEB)

    Yang, L.; Yang, J., E-mail: jyang@mail.hust.edu.cn; Liu, K. F.; Qin, B.; Chen, D. Z. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-06-15

    An insulated core transformer (ICT) power supply is an ideal high-voltage generator for irradiation accelerators with energy lower than 3 MeV. However, there is a significant problem that the structure of the segmented cores leads to an increase in the leakage flux and voltage differences between rectifier disks. A high level of consistency in the output of the disks helps to achieve a compact structure by improving the utilization of both the rectifier components and the insulation distances, and consequently increase the output voltage of the power supply. The output voltages of the disks which are far away from the primary coils need to be improved to reduce their inhomogeneity. In this study, by investigating and comparing the existing compensation methods, a new combined compensation method is proposed, which increases the turns on the secondary coils and employs parallel capacitors to improve the consistency of the disks, while covering the entire operating range of the power supply. This method turns out to be both feasible and effective during the development of an ICT power supply. The non-uniformity of the output voltages of the disks is less than 3.5% from no-load to full-load, and the power supply reaches an output specification of 350 kV/60 mA.

  16. A computational modeling approach of the jet-like acoustic streaming and heat generation induced by low frequency high power ultrasonic horn reactors.

    Science.gov (United States)

    Trujillo, Francisco Javier; Knoerzer, Kai

    2011-11-01

    High power ultrasound reactors have gained a lot of interest in the food industry given the effects that can arise from ultrasonic-induced cavitation in liquid foods. However, most of the new food processing developments have been based on empirical approaches. Thus, there is a need for mathematical models which help to understand, optimize, and scale up ultrasonic reactors. In this work, a computational fluid dynamics (CFD) model was developed to predict the acoustic streaming and induced heat generated by an ultrasonic horn reactor. In the model it is assumed that the horn tip is a fluid inlet, where a turbulent jet flow is injected into the vessel. The hydrodynamic momentum rate of the incoming jet is assumed to be equal to the total acoustic momentum rate emitted by the acoustic power source. CFD velocity predictions show excellent agreement with the experimental data for power densities higher than W(0)/V ≥ 25kWm(-3). This model successfully describes hydrodynamic fields (streaming) generated by low-frequency-high-power ultrasound. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  17. The effects of ultrasonic solidification on aluminum

    OpenAIRE

    Đorđević Slavko 1

    2003-01-01

    The effect of ultrasound on characteristics of solidified aluminum was shown. An ultrasonic head and ultrasonic system for modification was designed and applied to the crystallizing aluminum melt. The ultrasonic generator allows power of 50-500 W, amplitude of oscillations 10-100 um.m and the operating frequency of 25 kHz. Ultrasonic modification was done by ultrasound introduced from above into the melt. Microstructure photographs show decreasing of the grain size more than five times.

  18. The effects of ultrasonic solidification on aluminum

    Directory of Open Access Journals (Sweden)

    Đorđević Slavko 1

    2003-01-01

    Full Text Available The effect of ultrasound on characteristics of solidified aluminum was shown. An ultrasonic head and ultrasonic system for modification was designed and applied to the crystallizing aluminum melt. The ultrasonic generator allows power of 50-500 W, amplitude of oscillations 10-100 um.m and the operating frequency of 25 kHz. Ultrasonic modification was done by ultrasound introduced from above into the melt. Microstructure photographs show decreasing of the grain size more than five times.

  19. Wind Farm Active Power Dispatch for Output Power Maximizing Based on a Wind Turbine Control Strategy for Load Minimizing

    DEFF Research Database (Denmark)

    Zhang, Baohua; Hu, Weihao; Hou, Peng

    2015-01-01

    Inclusion of the wake effect in the wind farm control design (WF) can increase the total captured power by wind turbines (WTs), which is usually implemented by derating upwind WTs. However, derating the WT without a proper control strategy will increase the structural loads, caused by operation...... in stall mode. Therefore, the WT control strategy for derating operation should be considered in the attempt at maximizing the total captured power while reducing structural loads. Moreover, electrical power loss on the transmission system inside a WF is also not negligible for maximizing the total output...... power of the WF. In this paper, an optimal active power dispatch strategy based on a WT derating strategy and considering the transmission loss is proposed for maximizing the total output power. The active power reference of each WT is chosen as the optimization variable. A partial swarm optimizing...

  20. High quantum yield ZnO quantum dots synthesizing via an ultrasonication microreactor method.

    Science.gov (United States)

    Yang, Weimin; Yang, Huafang; Ding, Wenhao; Zhang, Bing; Zhang, Le; Wang, Lixi; Yu, Mingxun; Zhang, Qitu

    2016-11-01

    Green emission ZnO quantum dots were synthesized by an ultrasonic microreactor. Ultrasonic radiation brought bubbles through ultrasonic cavitation. These bubbles built microreactor inside the microreactor. The photoluminescence properties of ZnO quantum dots synthesized with different flow rate, ultrasonic power and temperature were discussed. Flow rate, ultrasonic power and temperature would influence the type and quantity of defects in ZnO quantum dots. The sizes of ZnO quantum dots would be controlled by those conditions as well. Flow rate affected the reaction time. With the increasing of flow rate, the sizes of ZnO quantum dots decreased and the quantum yields first increased then decreased. Ultrasonic power changed the ultrasonic cavitation intensity, which affected the reaction energy and the separation of the solution. With the increasing of ultrasonic power, sizes of ZnO quantum dots first decreased then increased, while the quantum yields kept increasing. The effect of ultrasonic temperature on the photoluminescence properties of ZnO quantum dots was influenced by the flow rate. Different flow rate related to opposite changing trend. Moreover, the quantum yields of ZnO QDs synthesized by ultrasonic microreactor could reach 64.7%, which is higher than those synthesized only under ultrasonic radiation or only by microreactor. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Linearised model for PV panel power output variation with changes ...

    Indian Academy of Sciences (India)

    PALLAVI BHARADWAJ

    2017-10-26

    Oct 26, 2017 ... change in system input, namely: irradiance and temperature, with its output, namely: array current and power. ... of a solar cell as shown in figure 1, with appropriate scaling according to ... measurement-based methods [8–13].

  2. Recent advances in automated ultrasonic inspection of Magnox power stations

    International Nuclear Information System (INIS)

    Wooldridge, A.B.

    2006-01-01

    Magnox Electric operates a number of Magnox nuclear power stations, some of which have presented difficult inspection challenges. This paper will describe recent advances in automated ultrasonic techniques which have enabled additional, fully effective and qualified inspections to be introduced. The examples chosen involve phased array inspection of fillet welds and the introduction of 3D data display and analysis using NDT Workbench. Ultrasonic phased arrays have been optimised for inspection of fillet welded structures where physical access for the operator is very awkward and the surfaces available for probe scanning are very restricted. In addition to controlling the beam direction and focus depth, the systems have also optimised the depth of field by varying the number of phased array elements fired at a given time. These phased array inspections are substantially superior in quality, reliability and speed compared with that achievable by conventional manual inspection. Analysis of automated ultrasonic data can be very time-consuming if defects are complex. NDT Workbench significantly improves data analysis for complex geometries and defects primarily because of the 3D data displays of multiple beams and automated logging of measurements. This system has been used in 2005 for data analysis of complex defects where sizing accuracy was particularly important. Both these inspection procedures have been formally qualified using the ENIQ (European Network for Inspection Qualification) Methodology. Such qualification was achieved more easily because of the rigorous in house training programmes established in each case and because the Technical Justifications referred to evidence from previous related qualifications whenever appropriate. The timely achievement of inspection qualification demonstrates that the new systems have reached sufficient maturity to be used with confidence for high quality inspections. (orig.)

  3. Ultrasonic inspection of steam generator tubes in Superphenix F.B.R. Power plant

    International Nuclear Information System (INIS)

    Gondard, C.

    1991-01-01

    An ultrasonic method has been developed to test of the S.G's tubes of SPX fast breeder reactor. A new type of rotating probes for cracks and wall thickness measurements have been built up and successfully tested. The data acquisition and processing system SPARTACUS was used; it allows high frequency digitalization and powerful signal processings using frequency representations. The actual performances were tested on natural defects under representative operating conditions

  4. Development of ultrasonic testing technique to inspect containment liners embedded in concrete on nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, H.; Kurozumi, Y. [Inst. of Nuclear Safety System, Incorporated, Mihama, Fukui (Japan); Kaneshima, Y. [The Kansai Electric Power Company, Inc., Mihama, Fukui (Japan)

    2004-07-01

    The purpose of this study is development of ultrasonic testing technique to inspect containment liners embedded in concrete on nuclear power plants. Integrity of containment liners on nuclear power plants can be secured by suitable present operation and maintenance. Furthermore, non-destructive testing technique to inspect embedded liners will ensure the integrity of the containment further. In order to develop the non-destructive testing technique, ultrasonic transducers were made newly and ultrasonic testing data acquisition and evaluation were carried out by using a mock-up. We adopted the surface shear horizontal (SH) wave, low frequency (0.3-0.5MHz), to be able to detect an echo from a defect against attenuation of ultrasonic waves due to long propagation in the liners and dispersion into concrete. We made transducers with three large active elements (40mm x 40mm) in a line which were equivalent to a 120mm width active element. Artificial hollows, {phi}200mm - 19mm depth (1/2thickness) and {phi}200mm - 9.5mm depth (1/4thickness), were made on a surface of a mock-up: carbon steel plate, 38mm thickness, 2,000mm length, 1000mm width. The surfaces of the plate were covered with concrete in order to simulate liners embedded in concrete. As a result of the examinations, the surface SH transducers could detect clearly the echo from the hollows at a distance of 1500mm. We evaluate that the newly made surface SH transducers with three elements have ability of detection of defects such as corrosion on the liners embedded in concrete. (author)

  5. Ultra-Fast Tracking Power Supply with 4th order Output Filter and Fixed-Frequency Hysteretic Control

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

    2008-01-01

    A practical solution is presented for the design of a non-isolated DC/DC power converter with very low output ripple voltage and very fast output voltage step response. The converter is intended for use as an envelope tracking power supply for an RFPA (Radio Frequency Power Amplifier) in a Tetra2...

  6. Automated ultrasonic inspection system for nuclear power stations

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    The automated system of ultrasonic inspection which was used to conduct weld inspections of the complex primary system of the Borselle PWR station is described. It relies upon mechanically traversing purpose designed multi-crystal ultrasonic probes along the welds. A number of probes are switched sequentially to provide a continuous scan. A typical scan rate of 120 scan/sec is achieved by a multiplexer capable of switching transmitter and receiver individually. The system has wide applications in other industries. (U.K.)

  7. Smoothing of Grid-connected Wind-Diesel Power Output Using Energy Capacitor System

    Directory of Open Access Journals (Sweden)

    Adel A. Elbaset

    2014-06-01

    Full Text Available This paper presents a small hybrid power system consists of two types of power generation; wind turbine and diesel generation, DG connected to power distribution system. The fluctuations like random nature of wind power, turbulent wind, and sudden changes in load demand create imbalances in power distribution that can affect the frequency and the voltage in the power system. So, addition of Energy capacitor System, ECS is useful for compensation of fluctuating power, since it is capable of controlling both active and reactive power simultaneously and can smooth the output power flow. Hence, this paper proposes herein a dynamic model and simulation of a grid connected wind/DG based-ECS with power flow controllers between load and generation. Moreover, the paper presents a study to analyze the leveling of output fluctuation of wind power with the installation of ECS. To control the power exchanged between the ECS system and the AC grid, a load Following Control, LFC based supervisor is proposed with the aim to minimize variations of the power generated by the diesel generator. The interesting performance of the proposed supervisor is shown with the help of simulations. The computer simulation program is confirmed on a realistic circuit model which implemented in the Simulink environment of Matlab and works as if on line.

  8. Output Power Smoothing Control for a Wind Farm Based on the Allocation of Wind Turbines

    Directory of Open Access Journals (Sweden)

    Ying Zhu

    2018-06-01

    Full Text Available This paper presents a new output power smoothing control strategy for a wind farm based on the allocation of wind turbines. The wind turbines in the wind farm are divided into control wind turbines (CWT and power wind turbines (PWT, separately. The PWTs are expected to output as much power as possible and a maximum power point tracking (MPPT control strategy combining the rotor inertia based power smoothing method is adopted. The CWTs are in charge of the output power smoothing for the whole wind farm by giving the calculated appropriate power. The battery energy storage system (BESS with small capacity is installed to be the support and its charge and discharge times are greatly reduced comparing with the traditional ESSs based power smoothing strategies. The simulation model of the permanent magnet synchronous generators (PMSG based wind farm by considering the wake effect is built in Matlab/Simulink to test the proposed power smoothing method. Three different working modes of the wind farm are given in the simulation and the simulation results verify the effectiveness of the proposed power smoothing control strategy.

  9. Probabilistic Physics-Based Risk Tools Used to Analyze the International Space Station Electrical Power System Output

    Science.gov (United States)

    Patel, Bhogila M.; Hoge, Peter A.; Nagpal, Vinod K.; Hojnicki, Jeffrey S.; Rusick, Jeffrey J.

    2004-01-01

    This paper describes the methods employed to apply probabilistic modeling techniques to the International Space Station (ISS) power system. These techniques were used to quantify the probabilistic variation in the power output, also called the response variable, due to variations (uncertainties) associated with knowledge of the influencing factors called the random variables. These uncertainties can be due to unknown environmental conditions, variation in the performance of electrical power system components or sensor tolerances. Uncertainties in these variables, cause corresponding variations in the power output, but the magnitude of that effect varies with the ISS operating conditions, e.g. whether or not the solar panels are actively tracking the sun. Therefore, it is important to quantify the influence of these uncertainties on the power output for optimizing the power available for experiments.

  10. Ultrasonic hot powder compaction of Ti-6Al-4V.

    Science.gov (United States)

    Abedini, Rezvan; Abdullah, Amir; Alizadeh, Yunes

    2017-07-01

    Power ultrasonic has been recently employed in a wide variety of manufacturing processes among which ultrasonic assisted powder compaction is a promising powder materials processing technique with significant industrial applications. The products manufactured by the powder metallurgy commonly consist of residual porosities, material impurities, structural non-homogeneities and residual stress. In this paper, it is aimed to apply power ultrasonic to the hot consolidation process of Ti-6Al-4V titanium alloy powder in order to improve mechanical properties. To do this, the effects of ultrasonic power and process temperature and pressure were considered and then deeply studied through a series of experiments. It was shown that the addition of ultrasonic vibration leads to a significant improvement in the consolidation performance and the mechanical strength of the fabricated specimens. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Model output statistics applied to wind power prediction

    Energy Technology Data Exchange (ETDEWEB)

    Joensen, A; Giebel, G; Landberg, L [Risoe National Lab., Roskilde (Denmark); Madsen, H; Nielsen, H A [The Technical Univ. of Denmark, Dept. of Mathematical Modelling, Lyngby (Denmark)

    1999-03-01

    Being able to predict the output of a wind farm online for a day or two in advance has significant advantages for utilities, such as better possibility to schedule fossil fuelled power plants and a better position on electricity spot markets. In this paper prediction methods based on Numerical Weather Prediction (NWP) models are considered. The spatial resolution used in NWP models implies that these predictions are not valid locally at a specific wind farm. Furthermore, due to the non-stationary nature and complexity of the processes in the atmosphere, and occasional changes of NWP models, the deviation between the predicted and the measured wind will be time dependent. If observational data is available, and if the deviation between the predictions and the observations exhibits systematic behavior, this should be corrected for; if statistical methods are used, this approaches is usually referred to as MOS (Model Output Statistics). The influence of atmospheric turbulence intensity, topography, prediction horizon length and auto-correlation of wind speed and power is considered, and to take the time-variations into account, adaptive estimation methods are applied. Three estimation techniques are considered and compared, Extended Kalman Filtering, recursive least squares and a new modified recursive least squares algorithm. (au) EU-JOULE-3. 11 refs.

  12. Case-based classification of ultrasonic b-scans: case-base organisation and case retrieval

    NARCIS (Netherlands)

    Jarmulak, J.

    1998-01-01

    Dutch Railways use a special train for the ultrasonic inspection of rails. The output of the ultrasonic scanning system installed on the train consists of echo images - so-called B-scans. The B-scans are classified according to the images of rail constructions, noise artefacts, and/or defects that

  13. Possible factors determining the non-linearity in the VO2-power output relationship in humans: theoretical studies.

    Science.gov (United States)

    Korzeniewski, Bernard; Zoladz, Jerzy A

    2003-08-01

    At low power output exercise (below lactate threshold), the oxygen uptake increases linearly with power output, but at high power output exercise (above lactate threshold) some additional oxygen consumption causes a non-linearity in the overall VO(2) (oxygen uptake rate)-power output relationship. The functional significance of this phenomenon for human exercise tolerance is very important, but the mechanisms underlying it remain unknown. In the present work, a computer model of oxidative phosphorylation in intact skeletal muscle developed previously is used to examine the background of this relationship in different modes of exercise. Our simulations demonstrate that the non-linearity in the VO(2)-power output relationship and the difference in the magnitude of this non-linearity between incremental exercise mode and square-wave exercise mode (constant power output exercise) can be generated by introducing into the model some hypothetical factor F (group of associated factors) that accumulate(s) in time during exercise. The performed computer simulations, based on this assumption, give proper time courses of changes in VO(2) and [PCr] after an onset of work of different intensities, including the slow component in VO(2), well matching the experimental results. Moreover, if it is assumed that the exercise terminates because of fatigue when the amount/intensity of F exceed some threshold value, the model allows the generation of a proper shape of the well-known power-duration curve. This fact suggests that the phenomenon of the non-linearity of the VO(2)-power output relationship and the magnitude of this non-linearity in different modes of exercise is determined by some factor(s) responsible for muscle fatigue.

  14. Automatic ultrasonic pre-service, and in-service inspection of pressurized components of the primary circuit of nuclear power stations

    International Nuclear Information System (INIS)

    Muller, G.P.; Hallermeier, L.; Heinrich, D.; Grabendorfer, W.; Rebrmann, M.

    1985-01-01

    Ultrasonic pre-service and especially in-service inspection activities on the primary circuit of nuclear power stations form an essential part of the maintenance work that must be performed throughout the lifetime to ensure plant integrity. Consequently, the equipment required to carry out these inspections must be continuously improved in respect of reliability, safety, accuracy and ease of handling in order to minimize disturbances and repairs and reduce radiation exposure of the personnel. The authors' discussion of technique, equipment and performance of automated ultrasonic inspection is based on 15 years of experience in the testing of components of the primary circuit in nuclear power stations. To cover all inspection areas of the RPV of a PWR, four different manipulators are required, two for the closure head, one for the studs and one for the cylindrical shell and bottom closure. The use of the newly developed equipment, which naturally meets all the recommendations of the licensing authorities, allows for the automatic inspection of the components of primary circuit of nuclear power stations and the thus helps to substantially decrease the radiation exposure of the personnel. All the manipulators and their control consoles were designed and manufactured by M.A.N., Nuremberg while the ultrasonic electronic system was developed by Krautkramer, Cologne

  15. Forecasting the daily power output of a grid-connected photovoltaic system based on multivariate adaptive regression splines

    International Nuclear Information System (INIS)

    Li, Yanting; He, Yong; Su, Yan; Shu, Lianjie

    2016-01-01

    Highlights: • Suggests a nonparametric model based on MARS for output power prediction. • Compare the MARS model with a wide variety of prediction models. • Show that the MARS model is able to provide an overall good performance in both the training and testing stages. - Abstract: Both linear and nonlinear models have been proposed for forecasting the power output of photovoltaic systems. Linear models are simple to implement but less flexible. Due to the stochastic nature of the power output of PV systems, nonlinear models tend to provide better forecast than linear models. Motivated by this, this paper suggests a fairly simple nonlinear regression model known as multivariate adaptive regression splines (MARS), as an alternative to forecasting of solar power output. The MARS model is a data-driven modeling approach without any assumption about the relationship between the power output and predictors. It maintains simplicity of the classical multiple linear regression (MLR) model while possessing the capability of handling nonlinearity. It is simpler in format than other nonlinear models such as ANN, k-nearest neighbors (KNN), classification and regression tree (CART), and support vector machine (SVM). The MARS model was applied on the daily output of a grid-connected 2.1 kW PV system to provide the 1-day-ahead mean daily forecast of the power output. The comparisons with a wide variety of forecast models show that the MARS model is able to provide reliable forecast performance.

  16. Ultrasonic in-service testing of pressure vessel bodies of nuclear power reactors

    International Nuclear Information System (INIS)

    Obraz, J.

    1978-01-01

    In-service ultrasonic testing of reactor pressure vessels is described using a system of probes for simultaneous testing of material or weld joint thicknesses. The signal is transmitted from a common output via a 30 m long cable to electronic evaluation equipment. The methods are described of ultrasonic detection of fatigue cracks. The static calculation of the dependence of echo amplitudes on crack orientation and the dynamic calculation of the crack orientation effect are described for the indirect reflection technique. In testing, angular probes with gap-type acoustic coupling operating at a frequency of 2 MHz were preferably used. For detecting planar defects of more than 10 mm in size inclined by more than +-10deg probes operating at a frequency of 1 MHz were more advantageous. The direct reflection technique is suitable for detecting defects near the surface (10 to 20 mm) and for cases when the indirect reflection technique cannot be used. For this technique a focusing probe operating at a frequency of 2 MHz is suitable. The strong dependence of the echo amplitude on the crack depth is a disadvantage of the technique. Defects near the surface, i.e., immediately under cladding are best detected by means of a double probe transmitting transversal waves at an angle of 60deg. Experimental measurements were carried out on materials with artificial defects of the type of bores with flat bottom. (J.P.)

  17. Automatic ultrasonic testing and the LOFT in-service inspection program

    International Nuclear Information System (INIS)

    Hunter, J.A.

    1980-01-01

    An automatic ultrasonic testing system has been developed which significantly improves the flaw indication detection and characterization capability over the capability of conventional volumetric examination techniques. The system utilizes an accurately located ultrasonic sensor to generate the examination data. A small computer performs and integrates control and data input/output functions. Computer software has been developed to provide a rigorous method for data analysis and ultrasonic image interpretation. The system has been used as part of an in-service inspection program to examine welds in thich austenitic stainless steel pipes in a small experimental nuclear reactor

  18. Ultrasound propagation in steel piping at electric power plant using clamp-on ultrasonic pulse doppler velocity-profile flowmeter

    International Nuclear Information System (INIS)

    Tezuka, Kenichi; Mori, Michitsugu; Wada, Sanehiro; Aritomi, Masanori; Kikura, Hiroshige

    2008-01-01

    Venturi nozzles are widely used to measure the flow rates of reactor feedwater. This flow rate of nuclear reactor feedwater is an important factor in the operation of nuclear power reactors. Some other types of flowmeters have been proposed to improve measurement accuracy. The ultrasonic pulse Doppler velocity-profile flowmeter is expected to be a candidate method because it can measure the flow profiles across the pipe cross sections. For the accurate estimation of the flow velocity, the incidence angle of ultrasonic entering the fluid should be carefully estimated by the theoretical approach. However, the evaluation of the ultrasound propagation is not straightforward for the several reasons such as temperature gradient in the wedge or mode conversion at the interface between the wedge and pipe. In recent years, the simulation code for ultrasound propagation has come into use in the nuclear field for nondestructive testing. This article analyzes and discusses ultrasound propagation in steel piping and water, using the 3D-FEM simulation code and the Kirchhoff method, as it relates to the flow profile measurements in power plants with the ultrasonic pulse Doppler velocity-profile flowmeter. (author)

  19. Balancing Europe's wind power output through spatial deployment informed by weather regimes.

    Science.gov (United States)

    Grams, Christian M; Beerli, Remo; Pfenninger, Stefan; Staffell, Iain; Wernli, Heini

    2017-08-01

    As wind and solar power provide a growing share of Europe's electricity1, understanding and accommodating their variability on multiple timescales remains a critical problem. On weekly timescales, variability is related to long-lasting weather conditions, called weather regimes2-5, which can cause lulls with a loss of wind power across neighbouring countries6. Here we show that weather regimes provide a meteorological explanation for multi-day fluctuations in Europe's wind power and can help guide new deployment pathways which minimise this variability. Mean generation during different regimes currently ranges from 22 GW to 44 GW and is expected to triple by 2030 with current planning strategies. However, balancing future wind capacity across regions with contrasting inter-regime behaviour - specifically deploying in the Balkans instead of the North Sea - would almost eliminate these output variations, maintain mean generation, and increase fleet-wide minimum output. Solar photovoltaics could balance low-wind regimes locally, but only by expanding current capacity tenfold. New deployment strategies based on an understanding of continent-scale wind patterns and pan-European collaboration could enable a high share of wind energy whilst minimising the negative impacts of output variability.

  20. Estimation of PV output power in moving and rocking hybrid energy marine ships

    International Nuclear Information System (INIS)

    Liu, Hongda; Zhang, Qing; Qi, Xiaoxia; Han, Yang; Lu, Fang

    2017-01-01

    Highlights: •A mathematical model for characterizing the ship PV output power is developed. •The impacts of the sea condition and ship type on the PV output power are analyzed. •The hybrid energy storage system is used to stabilize the PV fluctuation powers. •A SC configuration method based on maximum half period is applied. -- Abstract: In recent years, the application of solar energy and energy storage to ship power systems has shown promise as a method for both reducing annual carbon and nitrogen oxide emissions and improving ship energy efficiency in the maritime shipping industry. When a ship navigates at sea, it encounters a constant rocking motion that is affected by both the surrounding sea conditions and the ship’s navigation parameters. This motion increases the uncertainty involved in using solar energy and accelerates the aging of the ship’s energy storage battery to some extent. In this study, a universal mathematical model is established for the power generation by photovoltaic (PV) modules in which both the sea conditions and the ship’s integrated motion, including its basic movement along with the motion caused by rocking, are taken into account. Based on this model, the fluctuation characteristics of a ship’s PV output power are studied and determined using three different simulation scenarios. A binary energy storage scheme based on a decoupled PV output power is proposed in order to both stabilize the small-period PV power fluctuations and slow the aging of the actual battery caused by rocking. In addition, a super-capacitor (SC) configuration is constructed based on a maximum half cycle. Finally, the optimal energy storage capacities for this green ship are compared under both rocking and moving motion. In the case of rocking motion, the SCs are able to achieve an approximately 24.8–35.0% reduction in battery replacement. A shipping route between Shanghai, China and Sydney, Australia is considered to validate the practicality

  1. Tuning range and output power optimization of an external-cavity GaN diode laser at 455 nm

    DEFF Research Database (Denmark)

    Chi, Mingjun; Jensen, Ole Bjarlin; Petersen, Paul Michael

    2016-01-01

    In this paper we discuss how different feedback gratings affect the tuning range and the output power of external feedback diode laser systems. A tunable high-power narrow-spectrum external-cavity diode laser system around 455 nm is investigated. The laser system is based on a high-power GaN diode...... laser in a Littrow external-cavity. Both a holographic diffraction grating and a ruled diffraction grating are used as feedback elements in the external cavity. The output power, spectral bandwidth, and tunable range of the external cavity diode laser system are measured and compared with the two...... gratings at different injected currents. When the holographic grating is used, the laser system can be tuned over a range of 1.4 nm with an output power around 530 mW. When the ruled grating is used, the laser system can be tuned over a range of 6.0 nm with an output power around 80 mW. The results can...

  2. A diode-pumped continuous-wave Nd:YAG laser with an average output power of 1 kW

    International Nuclear Information System (INIS)

    Lee, Sung Man; Cha, Byung Heon; Kim, Cheol Jung

    2004-01-01

    A diode-pumped Nd:YAG laser with an average output power of 1 kW is developed for industrial applications, such as metal cutting, precision welding, etc. To develop such a diode-pumped high power solid-state laser, a series of laser modules have been used in general with and without thermal birefringence compensation. For example, Akiyama et al. used three laser modules to obtain a output power of 5.4 kW CW.1 In the side-pumped Nd:YAG laser, which is a commonly used pump scheme to obtain high output power, the crystal rod has a short thermal focal length at a high input pump power, and the short thermal focal length in turn leads to beam distortion within a laser resonator. Therefore, to achieve a high output power with good stability, isotropic beam profile, and high optical efficiency, the detailed analysis of the resonator stability condition depending on both mirror distances and a crystal separation is essential

  3. Maximal power output during incremental exercise by resistance and endurance trained athletes.

    Science.gov (United States)

    Sakthivelavan, D S; Sumathilatha, S

    2010-01-01

    This study was aimed at comparing the maximal power output by resistance trained and endurance trained athletes during incremental exercise. Thirty male athletes who received resistance training (Group I) and thirty male athletes of similar age group who received endurance training (Group II) for a period of more than 1 year were chosen for the study. Physical parameters were measured and exercise stress testing was done on a cycle ergometer with a portable gas analyzing system. The maximal progressive incremental cycle ergometer power output at peak exercise and carbon dioxide production at VO2max were measured. Highly significant (P biofeedback and perk up the athlete's performance.

  4. Non-linear relationship between O2 uptake and power output at high intensities of exercise in humans.

    Science.gov (United States)

    Zoladz, J A; Rademaker, A C; Sargeant, A J

    1995-01-01

    1. A slow component to pulmonary oxygen uptake (VO2) is reported during prolonged high power exercise performed at constant power output at, or above, approximately 60% of the maximal oxygen uptake. The magnitude of the slow component is reported to be associated with the intensity of exercise and to be largely accounted for by an increased VO2 across the exercising legs. 2. On the assumption that the control mechanism responsible for the increased VO2 is intensity dependent we hypothesized that it should also be apparent in multi-stage incremental exercise tests with the result that the VO2-power output relationship would be curvilinear. 3. We further hypothesized that the change in the VO2-power output relationship could be related to the hierarchical recruitment of different muscle fibre types with a lower mechanical efficiency. 4. Six subjects each performed five incremental exercise tests, at pedalling rates of 40, 60, 80, 100 and 120 rev min-1, over which range we expected to vary the proportional contribution of different fibre types to the power output. Pulmonary VO2 was determined continuously and arterialized capillary blood was sampled and analysed for blood lactate concentration ([lactate]b). 5. Below the level at which a sustained increase in [lactate]b was observed pulmonary VO2 showed a linear relationship with power output; at high power outputs, however, there was an additional increase in VO2 above that expected from the extrapolation of that linear relationship, leading to a positive curvilinear VO2-power output relationship. 6. No systematic effect on the magnitude or onset of the 'extra' VO2 was found in relation to pedalling rate, which suggests that it is not related to the pattern of motor unit recruitment in any simple way. PMID:8568657

  5. Mechanized ultrasonic examination of piping systems in nuclear power plants

    International Nuclear Information System (INIS)

    Edelmann, X.; Pfister, O.; Allidi, F.

    1988-01-01

    The success of mechanized ultrasonic examination applied on welds in piping systems in nuclear power plants is highly dependent on its careful preparation. From the development of an adequate examination technique to its implementation on site, many problems are to be solved. This is especially the case when dealing with austenitic welds or dissimilar metal welds. In addition to the specific needs for examination technique based on material properties and requirements for minimum flaw size detection, accessibility and radiation aspects have to be considered. A crew of skilled and highly trained examination personnel is required. Experience in various nuclear power plants, - BWR's and PWR's of different designs - has shown, that even difficult examination problems can be successfully solved, provided that there is a good preparation. The necessary step by step proceeding is illustrated by examples concerning mechanized examination. Preservice inspections and in-service inspections with specific requirements, due to the types of flaws to be found or the type of material concerned, are discussed

  6. High repetition ration solid state switched CO2 TEA laser employed in industrial ultrasonic testing of aircraft parts

    Science.gov (United States)

    von Bergmann, Hubertus; Morkel, Francois; Stehmann, Timo

    2015-02-01

    Laser Ultrasonic Testing (UT) is an important technique for the non-destructive inspection of composite parts in the aerospace industry. In laser UT a high power, short pulse probe laser is scanned across the material surface, generating ultrasound waves which can be detected by a second low power laser system and are used to draw a defect map of the part. We report on the design and testing of a transversely excited atmospheric pressure (TEA) CO2 laser system specifically optimised for laser UT. The laser is excited by a novel solid-state switched pulsing system and utilises either spark or corona preionisation. It provides short output pulses of less than 100 ns at repetition rates of up to 1 kHz, optimised for efficient ultrasonic wave generation. The system has been designed for highly reliable operation under industrial conditions and a long term test with total pulse counts in excess of 5 billion laser pulses is reported.

  7. Detailed simulation of ultrasonic inspections

    International Nuclear Information System (INIS)

    Chaplin, K.R.; Douglas, S.R.; Dunford, D.

    1997-01-01

    Simulation of ultrasonic inspection of engineering components have been performed at the Chalk River Laboratories of AECL for over 10 years. The computer model, called EWE for Elastic Wave Equations, solves the Elastic Wave Equations using a novel finite difference scheme. It simulates the propagation of an ultrasonic wave from the transducer to a flaw, the scatter of waves from the flaw, and measurement of signals at a receive transducer. Regions of different materials, water and steel for example, can be simulated. In addition, regions with slightly different material properties from the parent material can be investigated. The two major types of output are displays of the ultrasonic waves inside the component and the corresponding A-scans. EPRI and other organizations have used ultrasonic models for: defining acceptable ultrasonic inspection procedures, designing and evaluating inspection techniques, and for quantifying inspection reliability. The EWE model has been applied to the inspection of large pipes in a nuclear plant, gas pipeline welds and steam generator tubes. Most recent work has dealt with the ultrasonic inspection of pressure tubes in CANDU reactors. Pressure tube inspections can reliably detect and size defects; however, there are improvements that can be made. For example, knowing the sharpness of a flaw-tip is crucial for fitness for service assessments. Computer modelling of the ultrasonic inspection of flaws with different root radius has suggested inspection techniques that provide flaw tip radius information. A preliminary investigation of these methods has been made in the laboratory. The basis for the model will be reviewed at the presentation. Then the results of computer simulations will be displayed on a PC using an interactive program that analyzes simulated A-scans. This software tool gives inspection staff direct access to the results of computer simulations. (author)

  8. Predicting Power Output of Upper Body using the OMNI-RES Scale

    Directory of Open Access Journals (Sweden)

    Bautista Iker J.

    2014-12-01

    Full Text Available The main aim of this study was to determine the optimal training zone for maximum power output. This was to be achieved through estimating mean bar velocity of the concentric phase of a bench press using a prediction equation. The values for the prediction equation would be obtained using OMNI-RES scale values of different loads of the bench press exercise. Sixty males ( voluntarily participated in the study and were tested using an incremental protocol on a Smith machine to determine one repetition maximum (1RM in the bench press exercise. A linear regression analysis produced a strong correlation (r = -0.94 between rating of perceived exertion (RPE and mean bar velocity (Velmean. The Pearson correlation analysis between real power output (PotReal and estimated power (PotEst showed a strong correlation coefficient of r = 0.77, significant at a level of p = 0.01. Therefore, the OMNI-RES scale can be used to predict Velmean in the bench press exercise to control the intensity of the exercise. The positive relationship between PotReal and PotEst allowed for the identification of a maximum power-training zone.

  9. Investigation of geometric design in piezoelectric microelectromechanical systems diaphragms for ultrasonic energy harvesting

    Science.gov (United States)

    Shi, Qiongfeng; Wang, Tao; Kobayashi, Takeshi; Lee, Chengkuo

    2016-05-01

    Acoustic energy transfer (AET) has been widely used for contactless energy delivery to implantable devices. However, most of the energy harvesters (ultrasonic receivers) for AET are macro-scale transducers with large volume and limited operation bandwidth. Here, we propose and investigate two microelectromechanical systems diaphragm based piezoelectric ultrasonic energy harvesters (PUEHs) as an alternative for AET. The proposed PUEHs consist of micro-scale diaphragm array with different geometric parameter design. Diaphragms in PUEH-1 have large length to width ratio to achieve broadband property, while its energy harvesting performance is compromised. Diaphragms in PUEH-2 have smaller length to width ratio and thinner thickness to achieve both broadband property and good energy harvesting performance. Both PUEHs have miniaturized size and wide operation bandwidth that are ideally suitable to be integrated as power source for implantable biomedical devices. PUEH-1 has a merged -6 dB bandwidth of 74.5% with a central frequency of 350 kHz. PUEH-2 has two separate -6 dB bandwidth of 73.7%/30.8% with central frequencies of 285 kHz/650 kHz. They can adapt to various ultrasonic sources with different working frequency spectrum. Maximum output power is 34.3 nW and 84.3 nW for PUEH-1 and PUEH-2 at 1 mW/cm2 ultrasound intensity input, respectively. The associated power density is 0.734 μW/cm2 and 4.1 μW/cm2, respectively. Better energy harvesting performance is achieved for PUEH-2 because of the optimized length to width ratio and thickness design. Both PUEHs offer more alignment flexibility with more than 40% power when they are in the range of the ultrasound transmitter.

  10. Research on Power Output Characteristics of Magnetic Core in Energy Harvesting Devices

    Directory of Open Access Journals (Sweden)

    Rong-Ping GUO

    2014-07-01

    Full Text Available Magnetic core is the dominant factor in the performance of current transformer energy harvesting devices. The power output model of the magnetic core is established and verified through experiments. According to the actual application requirements, the concept of power density is proposed. The relationships of power density to air gap, material and dimension of the magnetic core are analyzed and verified through experiments.

  11. Calculation of the output power in self-amplified spontaneous radiation using scaling of power with number of simulation particles

    International Nuclear Information System (INIS)

    Yu, L.H.

    1998-01-01

    Recent advances in self-amplified spontaneous emission (SASE) experiments stimulate interest in quantitative comparison of measurements with theory. In this paper we show that the widely used simulation code TDA3D, developed by Tran and Wurtele [Comput. Phys. Commun. 54, 263 (1989)] even though a single frequency code, can be used to determine the output power in the SASE process with excellent approximation in the exponential growth regime. The method applies when the gain is not very high, which is a special advantage, because when the gain is not very high, the analytical calculation is particularly difficult since the exponential growing term does not dominate. The analysis utilizes a scaling relation between the output power and the number of simulation particles in the code TDA3D: left-angle P right-angle=N λ ' /N λ left-angle P ' right-angle, where left-angle P right-angle is the output power and N λ is the line density of the electrons, while left-angle P ' right-angle is the calculated output power using a line density N λ ' of the number of simulation particles in the code TDA3D. Because of the scaling property, the number of simulation particles can be taken to be many orders of magnitude less than the actual experiment. Comparison of our results with experiment yields new insight into the SASE process. copyright 1998 The American Physical Society

  12. Empirical investigation on using wind speed volatility to estimate the operation probability and power output of wind turbines

    International Nuclear Information System (INIS)

    Liu, Heping; Shi, Jing; Qu, Xiuli

    2013-01-01

    Highlights: ► Ten-minute wind speed and power generation data of an offshore wind turbine are used. ► An ARMA–GARCH-M model is built to simultaneously forecast wind speed mean and volatility. ► The operation probability and expected power output of the wind turbine are predicted. ► The integrated approach produces more accurate wind power forecasting than other conventional methods. - Abstract: In this paper, we introduce a quantitative methodology that performs the interval estimation of wind speed, calculates the operation probability of wind turbine, and forecasts the wind power output. The technological advantage of this methodology stems from the empowered capability of mean and volatility forecasting of wind speed. Based on the real wind speed and corresponding wind power output data from an offshore wind turbine, this methodology is applied to build an ARMA–GARCH-M model for wind speed forecasting, and then to compute the operation probability and the expected power output of the wind turbine. The results show that the developed methodology is effective, the obtained interval estimation of wind speed is reliable, and the forecasted operation probability and expected wind power output of the wind turbine are accurate

  13. Estimation of monthly wind power outputs of WECS with limited record period using artificial neural networks

    International Nuclear Information System (INIS)

    Tu, Yi-Long; Chang, Tsang-Jung; Chen, Cheng-Lung; Chang, Yu-Jung

    2012-01-01

    Highlights: ► ANN with short record training data is used to estimate power outputs in an existing station. ► The suitable numbers/parameters of input neurons for ANN are presented. ► Current wind speeds and previous power outputs are the most important input neurons. ► Choosing suitable input parameters is more important than choosing multiple parameters. - Abstract: For the brand new wind power industry, online recordings of wind power data are always in a relatively limited period. The aim of the study is to investigate the suitable numbers/parameters of input neurons for artificial neural networks under a short record of measured data. Measured wind speeds, wind directions (yaw angles) and power outputs with 10-min resolution at an existing wind power station, located at Jhongtun, Taiwan, are integrated to form three types of input neuron numbers and sixteen cases of input neurons. The first-10 days of each month in 2006 are used for data training to simulate the following 20-day power generation of the same month. The performance of various input neuron cases is evaluated. The simulated results show that using the first 10-day training data with adequate input neurons can estimate energy outputs well except the weak wind regime (May, June, and July). Among the input neuron parameters used, current wind speeds V(t) and previous power outputs P(t − 1) are the most important. Individually using one of them into input neurons can only provide satisfactory estimation. However, simultaneously using these two parameters into input neurons can give the best estimation. Thus, choosing suitable input parameters is more important than choosing multiple parameters.

  14. Smoothing Control of Wind Farm Output by Using Kinetic Energy of Variable Speed Wind Power Generators

    Science.gov (United States)

    Sato, Daiki; Saitoh, Hiroumi

    This paper proposes a new control method for reducing fluctuation of power system frequency through smoothing active power output of wind farm. The proposal is based on the modulation of rotaional kinetic energy of variable speed wind power generators through power converters between permanent magnet synchronous generators (PMSG) and transmission lines. In this paper, the proposed control is called Fluctuation Absorption by Flywheel Characteristics control (FAFC). The FAFC can be easily implemented by adding wind farm output signal to Maximum Power Point Tracking control signal through a feedback control loop. In order to verify the effectiveness of the FAFC control, a simulation study was carried out. In the study, it was assumed that the wind farm consisting of PMSG type wind power generator and induction machine type wind power generaotors is connected with a power sysem. The results of the study show that the FAFC control is a useful method for reducing the impacts of wind farm output fluctuation on system frequency without additional devices such as secondary battery.

  15. A study for soundness of turbine blade root using ultrasonic and phased array

    International Nuclear Information System (INIS)

    Gil, Doo Song; Park, Sang Ki; Cho, Yong Sang; Lee, Sang Gug; Huh, Kuang Bum

    2003-01-01

    Power plant is consisted of many component parts for the generation of the electricity and occasionally, turbine equipment may be caused in break-down because of the damage of the blade root. Phased array ultrasonic testing system has become available for power industry. This research describes the characteristics of phased array ultrasonic testing signal for various type of blade roots in thermal power plant turbines. This application of Phased array ultrasonic testing system has been promoted mainly to save inspection time and labor cost of turbine inspection. The characteristic of phased array ultrasonic testing signal for power plant component in very simple to understand but to difficult for perform the inspection. This paper is focused on the safety of the turbine equipment by the ultrasonic measurement and phased array analysis. As a result of the test through ultrasonic and phased array method, we have concluded that the main damage in these turbine blade roots parts could be generated by the concentrated stress and centrifugal force.

  16. Blue 450nm high power semiconductor continuous wave laser bars exceeding rollover output power of 80W

    Science.gov (United States)

    König, H.; Lell, A.; Stojetz, B.; Ali, M.; Eichler, C.; Peter, M.; Löffler, A.; Strauss, U.; Baumann, M.; Balck, A.; Malchus, J.; Krause, V.

    2018-02-01

    Industrial material processing like cutting or welding of metals is rather energy efficient using direct diode or diode pumped solid state lasers. However, many applications cannot be addressed by established infrared laser technology due to fundamental material properties of the workpiece: For example materials like copper or gold have too low absorption in the near infrared wavelength range to be processed efficiently by use of existing high power laser systems. The huge interest to enable high power kW systems with more suitable wavelengths in the blue spectral range triggered the German funded research project 'BLAULAS': Therein the feasibility and capability of CW operating high power laser bars based on the GaN material system was investigated by Osram and Laserline. High performance bars were enabled by defeating fundamental challenges like material quality as well as the chip processes, both of which differ significantly from well-known IR laser bars. The research samples were assembled on actively cooled heat sinks with hard solder technology. For the first time an output power of 98W per bar at 60A drive current was achieved. Conversion efficiency as high as 46% at 50W output power was demonstrated.

  17. Theoretical and experimental investigations of the limits to the maximum output power of laser diodes

    International Nuclear Information System (INIS)

    Wenzel, H; Crump, P; Pietrzak, A; Wang, X; Erbert, G; Traenkle, G

    2010-01-01

    The factors that limit both the continuous wave (CW) and the pulsed output power of broad-area laser diodes driven at very high currents are investigated theoretically and experimentally. The decrease in the gain due to self-heating under CW operation and spectral holeburning under pulsed operation, as well as heterobarrier carrier leakage and longitudinal spatial holeburning, are the dominant mechanisms limiting the maximum achievable output power.

  18. Increasing the solar cell power output by coating with transition metal-oxide nanorods

    International Nuclear Information System (INIS)

    Kuznetsov, I.A.; Greenfield, M.J.; Mehta, Y.U.; Merchan-Merchan, W.; Salkar, G.; Saveliev, A.V.

    2011-01-01

    Highlights: → Nanoparticles enhance solar cell efficiency. → Solar cell power increase by nanorod coating. → Metal-oxide nanorods are prepared in flames. → Molybdenum oxide nanorods effectively scatter light on solar cell surface. → Scattering efficiency depends on coating density. -- Abstract: Photovoltaic cells produce electric current through interactions among photons from an ambient light source and electrons in the semiconductor layer of the cell. However, much of the light incident on the panel is reflected or absorbed without inducing the photovoltaic effect. Transition metal-oxide nanoparticles, an inexpensive product of a process called flame synthesis, can cause scattering of light. Scattering can redirect photon flux, increasing the fraction of light absorbed in the thin active layer of silicon solar cells. This research aims to demonstrate that the application of transition metal-oxide nanorods to the surface of silicon solar panels can enhance the power output of the panels. Several solar panels were coated with a nanoparticle-methanol suspension, and the power outputs of the panels before and after the treatment were compared. The results demonstrate an increase in power output of up to 5% after the treatment. The presence of metal-oxide nanorods on the surface of the coated solar cells is confirmed by electron microscopy.

  19. High output power reluctance electric motors with bulk high-temperature superconductor elements

    Energy Technology Data Exchange (ETDEWEB)

    Kovalev, L.K. [Moscow State Aviation Institute (Technical University) (MAI), Moscow (Russian Federation)]. E-mail: kovalev@mail.sitek.net; Ilushin, K.V.; Penkin, V.T. [Moscow State Aviation Institute (Technical University) (MAI), Moscow (RU)] [and others

    2002-05-01

    We present new types of electric machines with the rotors containing bulk high-temperature superconductor (HTS)-YBCO and Bi-Ag-elements. We discuss different schematics of hysteresis, reluctance, 'trapped field' and composed synchronous HTS machines. The two-dimensional mathematical models describing the processes in such types of HTS machines were developed on the basis of the theoretical analysis of the electrodynamic and hysteresis processes in the single-domain and polycrystal YBCO ceramic samples and plate shape Bi-Ag elements. We give the test results of the series of hysteresis, reluctance, 'trapped field' and composed with permanent magnets HTS motors with an output power rating of 0.1-18 kW and current frequencies 50 Hz and 400 Hz. These results show that in the media of liquid nitrogen the specific output power per one unit weight of the HTS motor is four to seven times better than for conventional electric machines. A comparison of the theoretical and experimental characteristics of the developed HTS motors show that they are in good agreement. We discuss the test results for a liquid nitrogen cryogenic pump system with a hysteresis 500 W HTS motor. We describe several designs of new HTS motors operating in the media of liquid nitrogen with an output power 125 kW (and more) and a power factor of more than 0.8. We discuss future applications of new types of HTS motors for aerospace technology, on-land industry and transport systems. (author)

  20. Ultrasonic Stir Welding

    Science.gov (United States)

    Nabors, Sammy

    2015-01-01

    NASA Marshall Space Flight Center (MSFC) developed Ultrasonic Stir Welding (USW) to join large pieces of very high-strength metals such as titanium and Inconel. USW, a solid-state weld process, improves current thermal stir welding processes by adding high-power ultrasonic (HPU) energy at 20 kHz frequency. The addition of ultrasonic energy significantly reduces axial, frictional, and shear forces; increases travel rates; and reduces wear on the stir rod, which results in extended stir rod life. The USW process decouples the heating, stirring, and forging elements found in the friction stir welding process allowing for independent control of each process element and, ultimately, greater process control and repeatability. Because of the independent control of USW process elements, closed-loop temperature control can be integrated into the system so that a constant weld nugget temperature can be maintained during welding.

  1. Feasibility Study of Power Uprate Using Ultrasonic Flow Meters in NPPs

    International Nuclear Information System (INIS)

    Kim, Tae Mi; Heo, Gyun Young

    2010-01-01

    Feedwater flowrate is an important input parameter in establishing the plant's operating power level. In Korean nuclear power plants, venturi flow meters have been used for measuring the feedwater flow of the secondary side. However, as time goes on, the fouling in venture meters could cause measurement uncertainties to grow and that could lead to operation at less than about 2% of the licensed thermal power limit. In order to resolve the problem, nuclear power plants in other countries use Ultrasonic Flow Meters (UFMs) which have relatively lower measurement uncertainty (about 0.5%) instead of venturi flow meters and have reduced the errors from the fouling in venturi-type flow meters. USA amended 10 CFR 50 Appendix K so that US nuclear power plants can use real value of Core Operating Limit Supervisory System (COLSS) uncertainty, which is currently fixed as 2%, by adopting the UFM. Korea also has been amended the law in order to get benefits from the technology. In this study, we are going to present the fundamental principles of UFMs and the advantages and disadvantages of its installation. Also, we inquire into the conventional uses of UFMs in the overseas sites and then check what is needed to consider for its domestic application

  2. Variable gas spring for matching power output from FPSE to load of refrigerant compressor

    Science.gov (United States)

    Chen, Gong; Beale, William T.

    1990-01-01

    The power output of a free piston Stirling engine is matched to a gas compressor which it drives and its stroke amplitude is made relatively constant as a function of power by connecting a gas spring to the drive linkage from the engine to the compressor. The gas spring is connected to the compressor through a passageway in which a valve is interposed. The valve is linked to the drive linkage so it is opened when the stroke amplitude exceeds a selected limit. This allows compressed gas to enter the spring, increase its spring constant, thus opposing stroke increase and reducing the phase lead of the displacer ahead of the piston to reduce power output and match it to a reduced load power demand.

  3. Influence of power density and primer application on polymerization of dual-cured resin cements monitored by ultrasonic measurement.

    Science.gov (United States)

    Takubo, Chikako; Yasuda, Genta; Murayama, Ryosuke; Ogura, Yukari; Tonegawa, Motoka; Kurokawa, Hiroyasu; Miyazaki, Masashi

    2010-08-01

    We used ultrasonic measurements to monitor the influence of power density and primer application on the polymerization reaction of dual-cured resin cements. The ultrasonic equipment comprised a pulser-receiver, transducers, and an oscilloscope. Resin cements were mixed and inserted into a transparent mould, and specimens were placed on the sample stage, onto which the primer, if used, was also applied. Power densities of 0 (no irradiation), 200, or 600 mW cm(-2) were used for curing. The transit time through the cement disk was divided by the specimen thickness to obtain the longitudinal sound velocity. When resin cements were light-irradiated, each curve displayed an initial plateau of approximately 1,500 m s(-1), which rapidly increased to a second plateau of 2,300-2,900 m s(-1). The rate of sound velocity increase was retarded when the cements were light-irradiated at lower power densities, and increased when the primer was applied. The polymerization behaviour of dual-cured resin cements was therefore shown to be affected by the power density of the curing unit and the application of self-etching primer. (c) 2010 The Authors. Journal compilation (c) 2010 Eur J Oral Sci.

  4. Detecting, categorizing and forecasting large romps in wind farm power output using meteorological observations and WPPT

    DEFF Research Database (Denmark)

    Cutler, N.; Kay, M.; Jacka, K.

    2007-01-01

    The Wind Power Prediction Tool (WPPT) has been installed in Australia for the first time, to forecast the power output from the 65MW Roaring 40s Renewable Energy P/L Woolnorth Bluff Point wind form. This article analyses the general performance of WPPT as well as its performance during large romps...... (swings) in power output. In addition to this, detected large ramps are studied in detail and categorized. WPPT combines wind speed and direction forecasts from the Australian Bureau of Meteorology regional numerical weather prediction model, MesoLAPS, with real-time wind power observations to make hourly...... forecasts of the wind farm power output. The general performances of MesoLAPS and WPPTore evaluated over I year using the root mean square error (RMSE). The errors are significantly lower than for basic benchmark forecasts but higher than for many other WPPT installations, where the site conditions...

  5. Ultrasonic Linear Motor with Two Independent Vibrations

    Science.gov (United States)

    Muneishi, Takeshi; Tomikawa, Yoshiro

    2004-09-01

    We propose a new structure of an ultrasonic linear motor in order to solve the problems of high-power ultrasonic linear motors that drive the XY-stage for electron beam equipment and to expand the application fields of the motor. We pay special attention to the following three points: (1) the vibration in two directions of the ultrasonic linear motor should not influence mutually each other, (2) the vibration in two directions should be divided into the stage traveling direction and the pressing direction of the ultrasonic linear motor, and (3) the rigidity of the stage traveling direction of the ultrasonic linear motor should be increased. As a result, the supporting method of ultrasonic linear motors is simplified. The efficiency of the motor is improved and temperature rise is reduced. The stage position drift is also improved.

  6. Enhancing the power output of the VA-955 UHF-TV klystron

    International Nuclear Information System (INIS)

    Bowen, O.N.; Lawson, J.Q.

    1977-01-01

    The Varian VA-955 UHF-TV klystron is rated at 50 kW CW, and four of these klystrons were used to provide 200 kW of RF power for lower hybrid heating experiments on the ATC machine at 800 MHz. These proven, production-type tubes were wanted to generate more power for larger type machines, such as the PDX. Varian was asked whether the tubes were capable of higher-power operation in pulsed applications. They replied that they had no experimental data but felt that the tubes were capable of greatly enhanced performance under pulsed conditions. By using cathode modulation instead of modulating anode control of the klystron, and thus limiting the time that high voltage is applied to the cathode, it was shown that the tube is capable of an output power of 200 kW for tens of milliseconds compared to its normal CW rating of 50 kW. A description is given of the experimental results, the required modifications to the klystron and output transmission circuit, the details of operation of the regulating modulator used to perform the experiment. Upgrade kits are now being fabricated to allow 200 kW operation of the two 50 kW units which were lent to General Atomic for Doublet II experiments

  7. Predicting Power Output of Upper Body using the OMNI-RES Scale.

    Science.gov (United States)

    Bautista, Iker J; Chirosa, Ignacio J; Tamayo, Ignacio Martín; González, Andrés; Robinson, Joseph E; Chirosa, Luis J; Robertson, Robert J

    2014-12-09

    The main aim of this study was to determine the optimal training zone for maximum power output. This was to be achieved through estimating mean bar velocity of the concentric phase of a bench press using a prediction equation. The values for the prediction equation would be obtained using OMNI-RES scale values of different loads of the bench press exercise. Sixty males (age 23.61 2.81 year; body height 176.29 6.73 cm; body mass 73.28 4.75 kg) voluntarily participated in the study and were tested using an incremental protocol on a Smith machine to determine one repetition maximum (1RM) in the bench press exercise. A linear regression analysis produced a strong correlation (r = -0.94) between rating of perceived exertion (RPE) and mean bar velocity (Velmean). The Pearson correlation analysis between real power output (PotReal) and estimated power (PotEst) showed a strong correlation coefficient of r = 0.77, significant at a level of p = 0.01. Therefore, the OMNI-RES scale can be used to predict Velmean in the bench press exercise to control the intensity of the exercise. The positive relationship between PotReal and PotEst allowed for the identification of a maximum power-training zone.

  8. Remediation of Diesel Fuel Contaminated Sandy Soil using Ultrasonic Waves

    Directory of Open Access Journals (Sweden)

    Wulandari P.S.

    2010-01-01

    Full Text Available Ultrasonic cleaning has been used in industry for some time, but the application of ultrasonic cleaning in contaminated soil is just recently received considerable attention, it is a very new technique, especially in Indonesia. An ultrasonic cleaner works mostly by energy released from the collapse of millions of microscopic cavitations near the dirty surface. This paper investigates the use of ultrasonic wave to enhance remediation of diesel fuel contaminated sandy soil considering the ultrasonic power, soil particle size, soil density, water flow rate, and duration of ultrasonic waves application.

  9. Multiple regression approach to predict turbine-generator output for Chinshan nuclear power plant

    International Nuclear Information System (INIS)

    Chan, Yea-Kuang; Tsai, Yu-Ching

    2017-01-01

    The objective of this study is to develop a turbine cycle model using the multiple regression approach to estimate the turbine-generator output for the Chinshan Nuclear Power Plant (NPP). The plant operating data was verified using a linear regression model with a corresponding 95% confidence interval for the operating data. In this study, the key parameters were selected as inputs for the multiple regression based turbine cycle model. The proposed model was used to estimate the turbine-generator output. The effectiveness of the proposed turbine cycle model was demonstrated by using plant operating data obtained from the Chinshan NPP Unit 2. The results show that this multiple regression based turbine cycle model can be used to accurately estimate the turbine-generator output. In addition, this study also provides an alternative approach with simple and easy features to evaluate the thermal performance for nuclear power plants.

  10. Multiple regression approach to predict turbine-generator output for Chinshan nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Yea-Kuang; Tsai, Yu-Ching [Institute of Nuclear Energy Research, Taoyuan City, Taiwan (China). Nuclear Engineering Division

    2017-03-15

    The objective of this study is to develop a turbine cycle model using the multiple regression approach to estimate the turbine-generator output for the Chinshan Nuclear Power Plant (NPP). The plant operating data was verified using a linear regression model with a corresponding 95% confidence interval for the operating data. In this study, the key parameters were selected as inputs for the multiple regression based turbine cycle model. The proposed model was used to estimate the turbine-generator output. The effectiveness of the proposed turbine cycle model was demonstrated by using plant operating data obtained from the Chinshan NPP Unit 2. The results show that this multiple regression based turbine cycle model can be used to accurately estimate the turbine-generator output. In addition, this study also provides an alternative approach with simple and easy features to evaluate the thermal performance for nuclear power plants.

  11. 16 W output power by high-efficient spectral beam combining of DBR-tapered diode lasers

    DEFF Research Database (Denmark)

    Müller, André; Vijayakumar, Deepak; Jensen, Ole Bjarlin

    2011-01-01

    output power achieved by spectral beam combining of two single element tapered diode lasers. Since spectral beam combining does not affect beam propagation parameters, M2-values of 1.8 (fast axis) and 3.3 (slow axis) match the M2- values of the laser with lowest spatial coherence. The principle......Up to 16 W output power has been obtained using spectral beam combining of two 1063 nm DBR-tapered diode lasers. Using a reflecting volume Bragg grating, a combining efficiency as high as 93.7% is achieved, resulting in a single beam with high spatial coherence. The result represents the highest...... of spectral beam combining used in our experiments can be expanded to combine more than two tapered diode lasers and hence it is expected that the output power may be increased even further in the future....

  12. 16 W output power by high-efficient spectral beam combining of DBR-tapered diode lasers.

    Science.gov (United States)

    Müller, André; Vijayakumar, Deepak; Jensen, Ole Bjarlin; Hasler, Karl-Heinz; Sumpf, Bernd; Erbert, Götz; Andersen, Peter E; Petersen, Paul Michael

    2011-01-17

    Up to 16 W output power has been obtained using spectral beam combining of two 1063 nm DBR-tapered diode lasers. Using a reflecting volume Bragg grating, a combining efficiency as high as 93.7% is achieved, resulting in a single beam with high spatial coherence. The result represents the highest output power achieved by spectral beam combining of two single element tapered diode lasers. Since spectral beam combining does not affect beam propagation parameters, M2-values of 1.8 (fast axis) and 3.3 (slow axis) match the M2-values of the laser with lowest spatial coherence. The principle of spectral beam combining used in our experiments can be expanded to combine more than two tapered diode lasers and hence it is expected that the output power may be increased even further in the future.

  13. Output Control Technologies for a Large-scale PV System Considering Impacts on a Power Grid

    Science.gov (United States)

    Kuwayama, Akira

    The mega-solar demonstration project named “Verification of Grid Stabilization with Large-scale PV Power Generation systems” had been completed in March 2011 at Wakkanai, the northernmost city of Japan. The major objectives of this project were to evaluate adverse impacts of large-scale PV power generation systems connected to the power grid and develop output control technologies with integrated battery storage system. This paper describes the outline and results of this project. These results show the effectiveness of battery storage system and also proposed output control methods for a large-scale PV system to ensure stable operation of power grids. NEDO, New Energy and Industrial Technology Development Organization of Japan conducted this project and HEPCO, Hokkaido Electric Power Co., Inc managed the overall project.

  14. ULTRASONIC ASSEMBLY [REVIEW

    Directory of Open Access Journals (Sweden)

    PORAV Viorica

    2015-05-01

    Full Text Available The paper exposes the possibility of machine producesers to optimize the costs of clothes assembling. Ultrasonic systems being frequently utilized have many advantages on semi products of synthetic textile and technical textile. First of all, sewing – cutting process can be accomplished under high speeds and rate of losses can be minimized. Cutting seal applications are frequently used for underwear and sportswear. Slicing and unit cutting machines, as well as portable sealing machines are available for labeling sector. Products such as bag, pocket and cover can be sewed in a seamless manner for promotion purposes. All objects in terms of accessories are obtained in same standard. Our quilting machines are preferred in worldwide due to its threadless, high quality sealing. An alternative to the classic sewing assembly, with thread and needles is ultrasonic seaming. In ultrasonic welding, there are no connective bolts, nails, soldering materials, or adhesives necessary to bind the materials together. Ultrasonic is defined as acoustic frequencies above the range audible to the human ear. Ultrasonic frequencies are administered to the fabric from the sonotrode of bonding machine. The high frequency and powerful energy produced, when is release in one special environment, the ultrasound heating this environment. The ability to ultrasonic weld textiles and films depend on their thermoplastic contents and the desired end results. The paper defines the weld ability of more common textiles and films. The welding refers to all types of bonding and sealing, as in point bonding of fabric, or continuous sealing of film.

  15. Long-term WWER-440 dynamics in cyclic power output changes

    International Nuclear Information System (INIS)

    Petruzela, I.

    1989-01-01

    Xenon poisoning is one of the main factors limiting the operation of a nuclear power plant with a WWER-440 reactor in the variable load mode, when long-term dynamics applies to cyclic power output changes. An analysis of the xenon poisoning linearized transfer shows that a phase shift of 180deg takes place between the summed-up reactivity change due to a power change and the reactivity change due to xenon poisoning, this for a sine-wave power change with a period of 24 hours. Thus, the requirements are minimized for the change in reactivity of the control elements, and the maximum value can be achieved of released reactivity that can be utilized before the end of the campaign. (B.S.). 6 figs., 4 tabs., 9 refs

  16. A study for soundness of turbine blade root using ultrasonic and phased array

    International Nuclear Information System (INIS)

    Gil, Doo Song; Park, Sang Ki; Cho, Yong Sang; Lee, Sang Gug; Huh, Kuang Bum

    2003-01-01

    Power plant is consisted of many component parts for the generation of the electricity, and occasionally, turbine equipment may be caused in break-down because of the damage of the blade root. Phased array ultrasonic testing system has become available for practical application in complicated geometry such as turbine blade root, tenon, disc in power industry. This research describes the characteristics of phased array ultrasonic testing signal for various type of blade roots in thermal Power Plant turbines. This application of Phased array ultrasonic testing system has been promoted mainly to save inspection time and labor cost of turbine inspection. The characteristic of phased array ultrasonic testing signal for power plant component in very simple to understand but to difficult for perform the inspection. This paper is focused on the safety of the turbine equipment by the ultrasonic measurement and phased array analysis. As a result of the test through ultrasonic and phased array method, we have concluded that the main damage in these turbine blade root parts could be generated by the concentrated stress and centrifugal force.

  17. Loss of power output and laser fibre degradation during 120 watt lithium-triborate HPS laser vaporisation of the prostate

    Science.gov (United States)

    Hermanns, Thomas; Sulser, Tullio; Hefermehl, Lukas J.; Strebel, Daniel; Michel, Maurice-Stephan; Müntener, Michael; Meier, Alexander H.; Seifert, Hans-Helge

    2009-02-01

    It has recently been shown that laser fibre deterioration leads to a significant decrease of power output during 80 W potassium titanyl phosphate (KTP) laser vaporisation (LV) of the prostate. This decrease results in inefficient vaporisation especially towards the end of the procedure. For the new 120 W lithium-triborate (LBO) High Performance System (HPS) laser not only higher power but also changes in beam characteristics and improved fibre quality have been advertised. However, high laser power has been identified as a risk factor for laser fibre degradation. Between July and September 2008 25 laser fibres were investigated during routine 120 W LBO-LV in 20 consecutive patients. Laser beam power was measured at baseline and after the application of every 25 kJ during the LV procedure. Postoperatively, the surgeon subjectively rated the performance of the respective fibre on a scale from 1 to 4 (1 indicating perfect and 4 insufficient performance). Additionally, microscopic examination of the fibre tip was performed. Median energy applied was 212 kJ. Changes of power output were similar for all fibres. Typically, a steep decrease of power output within the first 50 kJ was followed by a continuous mild decrease until the end of the procedure. After the application of 50 kJ the median power output was 63% (58-73% interquartile range) of the baseline value. The median power output at the end of the 275 kJ-lifespan of the fibres was 42% (40-47%). The median surgeons' rating of the overall performance of the laser fibres was 2 and the median estimated final decrease of power output 60%. Some degree of degradation at the emission window was microscopically detectable in all cases after the procedure. However, even after the application of 275 kJ, these structural changes were only moderate. Minor degradation of the laser fibre was associated with a significant decrease of power output during 120 W LBO-LV. However, following an early, steep decrease, power output

  18. Ultrasonic Low-Friction Containment Plate for Thermal and Ultrasonic Stir Weld Processes

    Science.gov (United States)

    Graff, Karl; Short, Matt

    2013-01-01

    The thermal stir welding (TSW) process is finding applications in fabrication of space vehicles. In this process, workpieces to be joined by TSW are drawn, by heavy forces, between "containment plates," past the TSW tool that then causes joining of the separate plates. It is believed that the TSW process would be significantly improved by reducing the draw force, and that this could be achieved by reducing the friction forces between the workpieces and containment plates. Based on use of high-power ultrasonics in metal forming processes, where friction reduction in drawing dies has been achieved, it is believed that ultrasonic vibrations of the containment plates could achieve similar friction reduction in the TSW process. By applying ultrasonic vibrations to the containment plates in a longitudinal vibration mode, as well as by mounting and holding the containment plates in a specific manner such as to permit the plates to acoustically float, friction between the metal parts and the containment plates is greatly reduced, and so is the drawing force. The concept was to bring in the ultrasonics from the sides of the plates, permitting the ultrasonic hardware to be placed to the side, away from the equipment that contains the thermal stir tooling and that applies clamping forces to the plates. Tests demonstrated that one of the major objectives of applying ultrasonics to the thermal stir system, that of reducing draw force friction, should be achievable on a scaled-up system.

  19. Super short term forecasting of photovoltaic power generation output in micro grid

    Science.gov (United States)

    Gong, Cheng; Ma, Longfei; Chi, Zhongjun; Zhang, Baoqun; Jiao, Ran; Yang, Bing; Chen, Jianshu; Zeng, Shuang

    2017-01-01

    The prediction model combining data mining and support vector machine (SVM) was built. Which provide information of photovoltaic (PV) power generation output for economic operation and optimal control of micro gird, and which reduce influence of power system from PV fluctuation. Because of the characteristic which output of PV rely on radiation intensity, ambient temperature, cloudiness, etc., so data mining was brought in. This technology can deal with large amounts of historical data and eliminate superfluous data, by using fuzzy classifier of daily type and grey related degree. The model of SVM was built, which can dock with information from data mining. Based on measured data from a small PV station, the prediction model was tested. The numerical example shows that the prediction model is fast and accurate.

  20. Output power maximization of low-power wind energy conversion systems revisited: Possible control solutions

    Energy Technology Data Exchange (ETDEWEB)

    Vlad, Ciprian; Munteanu, Iulian; Bratcu, Antoneta Iuliana; Ceanga, Emil [' ' Dunarea de Jos' ' University of Galati, 47, Domneasca, 800008-Galati (Romania)

    2010-02-15

    This paper discusses the problem of output power maximization for low-power wind energy conversion systems operated in partial load. These systems are generally based on multi-polar permanent-magnet synchronous generators, who exhibit significant efficiency variations over the operating range. Unlike the high-power systems, whose mechanical-to-electrical conversion efficiency is high and practically does not modify the global optimum, the low-power systems global conversion efficiency is affected by the generator behavior and the electrical power optimization is no longer equivalent with the mechanical power optimization. The system efficiency has been analyzed by using both the maxima locus of the mechanical power versus the rotational speed characteristics, and the maxima locus of the electrical power delivered versus the rotational speed characteristics. The experimental investigation has been carried out by using a torque-controlled generator taken from a real-world wind turbine coupled to a physically simulated wind turbine rotor. The experimental results indeed show that the steady-state performance of the conversion system is strongly determined by the generator behavior. Some control solutions aiming at maximizing the energy efficiency are envisaged and thoroughly compared through experimental results. (author)

  1. Output power maximization of low-power wind energy conversion systems revisited: Possible control solutions

    International Nuclear Information System (INIS)

    Vlad, Ciprian; Munteanu, Iulian; Bratcu, Antoneta Iuliana; Ceanga, Emil

    2010-01-01

    This paper discusses the problem of output power maximization for low-power wind energy conversion systems operated in partial load. These systems are generally based on multi-polar permanent-magnet synchronous generators, who exhibit significant efficiency variations over the operating range. Unlike the high-power systems, whose mechanical-to-electrical conversion efficiency is high and practically does not modify the global optimum, the low-power systems global conversion efficiency is affected by the generator behavior and the electrical power optimization is no longer equivalent with the mechanical power optimization. The system efficiency has been analyzed by using both the maxima locus of the mechanical power versus the rotational speed characteristics, and the maxima locus of the electrical power delivered versus the rotational speed characteristics. The experimental investigation has been carried out by using a torque-controlled generator taken from a real-world wind turbine coupled to a physically simulated wind turbine rotor. The experimental results indeed show that the steady-state performance of the conversion system is strongly determined by the generator behavior. Some control solutions aiming at maximizing the energy efficiency are envisaged and thoroughly compared through experimental results.

  2. A study on Computer-controlled Ultrasonic Scanning Device

    International Nuclear Information System (INIS)

    Huh, H.; Park, C. S.; Hong, S. S.; Park, J. H.

    1989-01-01

    Since the nuclear power plants in Korea have been operated in 1979, the nondestructive testing (NDT) of pressure vessels and/or piping welds plays an important role for maintaining the safety and integrity of the plants. Ultrasonic method is superior to the other NDT method in the viewpoint of the detectability of small flaw and accuracy to determine the locations, sizes, orientations, and shapes. As the service time of the nuclear power plants is increased, the radiation level from the components is getting higher. In order to get more quantitative and reliable results and secure the inspector from the exposure to high radiation level, automation of the ultrasonic equipment has been one of the important research and development(R and D) subject. In this research, it was attempted to visualize the shape of flaws presented inside the specimen using a Modified C-Scan technique. In order to develop Modified C-Scan technique, an automatic ultrasonic scanner and a module to control the scanner were designed and fabricated. IBM-PC/XT was interfaced to the module to control the scanner. Analog signals from the SONIC MARK II were digitized by Analog-Digital Converter(ADC 0800) for Modified C-Scan display. A computer program has been developed and has capability of automatic data acquisition and processing from the digital data, which consist of maximum amplitudes in each gate range and locations. The data from Modified C-Scan results was compared with shape from artificial defects using the developed system. Focal length of focused transducer was measured. The automatic ultrasonic equipment developed through this study is essential for more accurate, reliable, and repeatable ultrasonic experiments. If the scanner are modified to meet to appropriate purposes, it can be applied to automation of ultrasonic examination of nuclear power plants and helpful to the research on ultrasonic characterization of the materials

  3. Ultrasonically enhanced disintegration. Polymers, sludge, and contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Groenroos, A.

    2010-05-15

    There are a great variety of potential applications of high-intensity ultrasonic energy. Of these, cleaning, plastic pounding, and at present also sludge disintegration and the remediation of contaminated soil are probably the best known and offer the most general market for high-intensity ultrasonics. All developments within the area of ultrasound applications lead to the creation of environmentally friendly processes and compounds, emphasizing the role of ultrasound in 'green chemistry'. Ultrasound technology is considered not easy to use in industrial processes, since devices providing high sonic energy are not easy to construct. This thesis investigates on a semi-pilot scale if it is possible to enhance the disintegration of three quite different samples: polymers, sludge, and contaminated soil by using ultrasound. The results indicate that it is possible to enhance the disintegration of polymers by means of ultrasonic power only when the cavitation threshold is exceeded. Above the cavitation threshold, the most extensive degradation took place at the lowest ultrasonic frequency used. The biggest decrease (from 115,000 g/mol to 30,000 g/mol) in relative molecular mass (RMM) was observed when the concentration of polyvinyl alcohol (PVA) was the lowest (1.0%). However, in the case of carboxymethylcellulose (CMC) it was observed that when viscosity was not adjusted there is an optimum polymer concentration (1.5-2.0%) where degradation is most efficient. The thesis shows that the extent of ultrasonic depolymerization decreases with decreasing molecular mass of the CMC polymer. The study also reveals that ultrasonic irradiation causes narrowing of the molecular mass distribution. The degradation of CMC polymer proceeded linearly and the rate of ultrasonic depolymerization decreased with decreasing molecular mass. In cases where the initial dynamic viscosities of polymer solutions were not the same, the sonolytic degradation of CMC polymer mainly depended

  4. Method for Prediction of the Power Output from Photovoltaic Power Plant under Actual Operating Conditions

    Science.gov (United States)

    Obukhov, S. G.; Plotnikov, I. A.; Surzhikova, O. A.; Savkin, K. D.

    2017-04-01

    Solar photovoltaic technology is one of the most rapidly growing renewable sources of electricity that has practical application in various fields of human activity due to its high availability, huge potential and environmental compatibility. The original simulation model of the photovoltaic power plant has been developed to simulate and investigate the plant operating modes under actual operating conditions. The proposed model considers the impact of the external climatic factors on the solar panel energy characteristics that improves accuracy in the power output prediction. The data obtained through the photovoltaic power plant operation simulation enable a well-reasoned choice of the required capacity for storage devices and determination of the rational algorithms to control the energy complex.

  5. Ultrasonic assisted hot metal powder compaction.

    Science.gov (United States)

    Abedini, Rezvan; Abdullah, Amir; Alizadeh, Yunes

    2017-09-01

    Hot pressing of metal powders is used in production of parts with similar properties to wrought materials. During hot pressing processes, particle rearrangement, plastic deformation, creep, and diffusion are of the most effective powder densification mechanisms. Applying ultrasonic vibration is thought to result in great rates of densification and therefore higher efficiency of the process is expected. This paper deals with the effects of power ultrasonic on the densification of AA1100 aluminum powder under constant applied stress. The effects of particle size and process temperature on the densification behavior are discussed. The results show that applying ultrasonic vibration leads to an improved homogeneity and a higher relative density. Also, it is found that the effect of ultrasonic vibration is greater for finer particles. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Improving power output of inertial energy harvesters by employing principal component analysis of input acceleration

    Science.gov (United States)

    Smilek, Jan; Hadas, Zdenek

    2017-02-01

    In this paper we propose the use of principal component analysis to process the measured acceleration data in order to determine the direction of acceleration with the highest variance on given frequency of interest. This method can be used for improving the power generated by inertial energy harvesters. Their power output is highly dependent on the excitation acceleration magnitude and frequency, but the axes of acceleration measurements might not always be perfectly aligned with the directions of movement, and therefore the generated power output might be severely underestimated in simulations, possibly leading to false conclusions about the feasibility of using the inertial energy harvester for the examined application.

  7. Utilizing Maximum Power Point Trackers in Parallel to Maximize the Power Output of a Solar (Photovoltaic) Array

    Science.gov (United States)

    2012-12-01

    completing the academic workload at NPS. Taking care of two toddlers all day, every day, is not an easy task. You make xxviii it seem effortless and...for the development of numerous thin-cell applications that meet the military’s requirements for ruggedness and power output. For example, the...2012, September 5). PV microinverters and power optimizers set for significant growth [PV Magazine Online]. Available: http://www.pv- magazine.com

  8. Control Strategies for Smoothing of Output Power of Wind Energy Conversion Systems

    Science.gov (United States)

    Pratap, Alok; Urasaki, Naomitsu; Senju, Tomonobu

    2013-10-01

    This article presents a control method for output power smoothing of a wind energy conversion system (WECS) with a permanent magnet synchronous generator (PMSG) using the inertia of wind turbine and the pitch control. The WECS used in this article adopts an AC-DC-AC converter system. The generator-side converter controls the torque of the PMSG, while the grid-side inverter controls the DC-link and grid voltages. For the generator-side converter, the torque command is determined by using the fuzzy logic. The inputs of the fuzzy logic are the operating point of the rotational speed of the PMSG and the difference between the wind turbine torque and the generator torque. By means of the proposed method, the generator torque is smoothed, and the kinetic energy stored by the inertia of the wind turbine can be utilized to smooth the output power fluctuations of the PMSG. In addition, the wind turbines shaft stress is mitigated compared to a conventional maximum power point tracking control. Effectiveness of the proposed method is verified by the numerical simulations.

  9. High power CW output from low confinement asymmetric structure diode laser

    NARCIS (Netherlands)

    Iordache, G.; Buda, M.; Acket, G.A.; Roer, van de T.G.; Kaufmann, L.M.F.; Karouta, F.; Jagadish, C.; Tan, H.H.

    1999-01-01

    High power continuous wave output from diode lasers using low loss, low confinement, asymmetric structures is demonstrated. An asymmetric structure with an optical trap layer was grown by metal organic vapour phase epitaxy. Gain guided 50 µm wide stripe 1-3 mm long diode lasers were studied. 1.8 W

  10. Ultrasonic nondestructive materials characterization

    Science.gov (United States)

    Green, R. E., Jr.

    1986-01-01

    A brief review of ultrasonic wave propagation in solid materials is presented with consideration of the altered behavior in anisotropic and nonlinear elastic materials in comparison with isotropic and linear elastic materials. Some experimental results are described in which ultrasonic velocity and attenuation measurements give insight into materials microstructure and associated mechanical properties. Recent developments with laser beam non-contact generation and detection of ultrasound are presented. The results of several years of experimental measurements using high-power ultrasound are discussed, which provide substantial evidence of the inability of presently accepted theories to fully explain the interaction of ultrasound with solid materials. Finally, a special synchrotron X-ray topographic system is described which affords the possibility of observing direct interaction of ultrasonic waves with the microstructural features of real crystalline solid materials for the first time.

  11. Improvement of Output Power of ECF Micromotor

    Science.gov (United States)

    Yokota, Shinichi; Kawamura, Kiyomi; Takemura, Kenjiro; Edamura, Kazuya

    Electro-conjugate fluid (ECF) is a kind of dielectric fluids, which produces jet-flow (ECF jet) when subjected to a high DC voltage. By using the ECF jet, a new type of micromotor with simple structure and lightweight can be realized. Up to now, we developed a disk-plate type ECF micromotor with inner diameter of 9 mm. In this study, we develope novel ECF micromotors with inner diameter of 5 mm in order to improve the output power density. First, we designed and produced the ECF micromotors with 4-layered and 8-layered disk plate rotors. Then, the performances of the motors are measured. The experimental results confirm the motor developed has a higher performance than the previous ones.

  12. Ultrasonic Bat Deterrent Technology

    Energy Technology Data Exchange (ETDEWEB)

    Kinzie, Kevin; Rominger, Kathryn M.

    2017-12-14

    The project objective was to advance the development and testing of an Near commercial bat-deterrent system with a goal to increase the current GE deterrent system effectiveness to over 50% with broad species applicability. Additionally, the research supported by this program has provided insights into bat behavior and ultrasonic deterrent design that had not previously been explored. Prior research and development had demonstrated the effectiveness of a commercial-grade, air-powered, ultrasonic bat deterrent to be between 30-50% depending upon the species of bat. However, the previous research provided limited insight into the behavioral responses of bats in the presence of ultrasonic deterrent sound fields that could be utilized to improve effectiveness. A unique bat flight room was utilized to observe the behavioral characteristics of bats in the presence of ultrasonic sound fields. Behavioral testing in the bat flight facility demonstrated that ultrasonic sounds similar to those produced by the GE deterrent influenced the activities and behaviors, primarily those associated with foraging, of the species exposed. The study also indicated that continuous and pulsing ultrasonic signals had a similar effect on the bats, and confirmed that as ultrasonic sounds attenuate, their influence on the bats’ activities and behavior decreases. Ground testing at Wolf Ridge Wind, LLC and Shawnee National Forest assessed both continuous and pulsing deterrent signals emitted from the GE deterrent system and further enhanced the behavioral understanding of bats in the presence of the deterrent. With these data and observations, the existing 4-nozzle continuous, or steady, emission ultrasonic system was redesigned to a 6-nozzle system that could emit a pulsing signal covering a larger air space around a turbine. Twelve GE 1.6-100 turbines were outfitted with the deterrent system and a formal three-month field study was performed using daily carcass searches beneath the 12

  13. Simulation of the output power of copper bromide lasers by the MARS method

    International Nuclear Information System (INIS)

    Iliev, I P; Voynikova, D S; Gocheva-Ilieva, S G

    2012-01-01

    The dependence of the output power of CuBr lasers (operating at wavelengths of 510.6 and 578.2 nm) on ten input physical parameters has been statistically analysed based on a large amount of experimental data accumulated for these lasers. Regression models have been built using the flexible nonparametric method of multivariate adaptive regression splines (MARS) to describe both linear and nonlinear local dependences. These models cover more than 97% initial data with an error comparable with the experimental error; they are applied to estimate and predict the output powers of both existing and future lasers. The advantage of the models constructed for estimating laser parameters over the standard parametric methods of multivariate factor and regression analysis is demonstrated.

  14. Aerobic capacity and peak power output of elite quadriplegic games players

    Science.gov (United States)

    Goosey‐Tolfrey, V; Castle, P; Webborn, N

    2006-01-01

    Background Participation in wheelchair sports such as tennis and rugby enables people with quadriplegia to compete both individually and as a team at the highest level. Both sports are dominated by frequent, intermittent, short term power demands superimposed on a background of aerobic activity. Objective To gain physiological profiles of highly trained British quadriplegic athletes, and to examine the relation between aerobic and sprint capacity. Methods Eight male quadriplegic athletes performed an arm crank exercise using an ergometer fitted with a Schoberer Rad Messtechnik (SRM) powermeter. The sprint test consisted of three maximum‐effort sprints of five seconds duration against a resistance of 2%, 3%, and 4% of body mass. The highest power output obtained was recorded (PPO). Peak oxygen consumption (V̇o2peak), peak heart rate (HRpeak), and maximal power output (POaer) were determined. Results Mean POaer was 67.7 (16.2) W, mean V̇o2peak was 0.96 (0.17) litres/min, and HRpeak was 134 (19) beats/min for the group. There was high variability among subjects. Peak power over the five second sprint for the group was 220 (62) W. There was a significant correlation between V̇o2peak (litres/min) and POaer (W) (r  =  0.74, p<0.05). Conclusions These British quadriplegic athletes have relatively high aerobic fitness when compared with the available literature. Moreover, the anaerobic capacity of these athletes appeared to be relatively high compared with paraplegic participants. PMID:16611721

  15. Comparison of Solar and Wind Power Output and Correlation with Real-Time Pricing

    Science.gov (United States)

    Hoepfl, Kathryn E.; Compaan, Alvin D.; Solocha, Andrew

    2011-03-01

    This study presents a method that can be used to determine the least volatile power output of a wind and solar hybrid energy system in which wind and solar systems have the same peak power. Hourly data for wind and PV systems in Northwest Ohio are used to show that a combination of both types of sustainable energy sources produces a more stable power output and would be more valuable to the grid than either individually. This method could be used to determine the ideal ratio in any part of the country and should help convince electric utility companies to bring more renewable generation online. This study also looks at real-time market pricing and how each system (solar, wind, and hybrid) correlates with 2009 hourly pricing from the Midwest Interconnect. KEH acknowledges support from the NSF-REU grant PHY-1004649 to the Univ. of Toledo and Garland Energy Systems/Ohio Department of Development.

  16. Ultrasonic Testing

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyeong Jun; Kuk, Jeong Han

    2002-02-15

    This book introduces ultrasonic testing, which tells of outline of ultrasonic testing, principle of ultrasonic testing, prosperities of ultrasonic waves, radiographic test and ultrasonic test, basic theory on ultrasonic testing, mode conversion, transmission and diffraction, ultrasonic flaw detection and probe, standard test piece and reference test piece, like KS(JIS) ASME and ASTM, classification and properties of ultrasonic testing, straight beam method, angle beam method, ASME SEC.V.Art.5 ASTMA 388 and KS B 0817 Korean industrial standard.

  17. Optimal Output of Distributed Generation Based On Complex Power Increment

    Science.gov (United States)

    Wu, D.; Bao, H.

    2017-12-01

    In order to meet the growing demand for electricity and improve the cleanliness of power generation, new energy generation, represented by wind power generation, photovoltaic power generation, etc has been widely used. The new energy power generation access to distribution network in the form of distributed generation, consumed by local load. However, with the increase of the scale of distribution generation access to the network, the optimization of its power output is becoming more and more prominent, which needs further study. Classical optimization methods often use extended sensitivity method to obtain the relationship between different power generators, but ignore the coupling parameter between nodes makes the results are not accurate; heuristic algorithm also has defects such as slow calculation speed, uncertain outcomes. This article proposes a method called complex power increment, the essence of this method is the analysis of the power grid under steady power flow. After analyzing the results we can obtain the complex scaling function equation between the power supplies, the coefficient of the equation is based on the impedance parameter of the network, so the description of the relation of variables to the coefficients is more precise Thus, the method can accurately describe the power increment relationship, and can obtain the power optimization scheme more accurately and quickly than the extended sensitivity method and heuristic method.

  18. Ultrasonic enhancement of lipase-catalysed transesterification for biodiesel synthesis.

    Science.gov (United States)

    Bhangu, Sukhvir Kaur; Gupta, Shweta; Ashokkumar, Muthupandian

    2017-01-01

    The production of biodiesel was carried out from canola oil and methanol catalysed by lipase from Candida rugosa under different ultrasonic experimental conditions using horn (20kHz) and plate (22, 44, 98 and 300kHz) transducers. The effects of experimental conditions such as horn tip diameter, ultrasonic power, ultrasonic frequency and enzyme concentrations on biodiesel yield were investigated. The results showed that the application of ultrasound decreased the reaction time from 22-24h to 1.5h with the use of 3.5cm ultrasonic horn, an applied power of 40W, methanol to oil molar ratio of 5:1 and enzyme concentration of 0.23wt/wt% of oil. Low intensity ultrasound is efficient and a promising tool for the enzyme catalysed biodiesel synthesis as higher intensities tend to inactivate the enzyme and reduce its efficiency. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Ultrasonic testing of materials at level 2

    International Nuclear Information System (INIS)

    1988-06-01

    Ultrasonic inspection is a nondestructive method in which high frequency sound waves are introduced into the material being inspected. Ultrasonic testing has a superior penetrating power to radiography and can detect flaws deep in the test specimen (say up to about 6 to 7 meters of steel). It is quite sensitive to small flaws and allows the precise determination of the location and size of the flaws. Basic ultrasonic test methods such as the through transmission method and the resonance method, sensors and testing techniques are described. Pulse echo type flaw detectors and their applications for inspection of welds are surveyed. Ultrasonic standards, calibration of the equipment and evaluation methods are presented. Examples of practical applications in welding, casting and forging processes are given. Figs and tabs

  20. Development of transfer standard devices for ensuring the accurate calibration of ultrasonic physical therapy machines in clinical use

    International Nuclear Information System (INIS)

    Hekkenberg, R T; Richards, A; Beissner, K; Zeqiri, B; Prout, G; Cantrall, Ch; Bezemer, R A; Koch, Ch; Hodnett, M

    2004-01-01

    Physical therapy ultrasound is widely applied to patients. However, many devices do not comply with the relevant standard stating that the actual power output shall be within ±20% of the device indication. Extreme cases have been reported: from delivering effectively no ultrasound or operating at maximum power at all powers indicated. This can potentially lead to patient injury as well as mistreatment. The present European (EC) project is an ongoing attempt to improve the quality of the treatment of patients being treated with ultrasonic physical-therapy. A Portable ultrasound Power Standard (PPS) is being developed and accurately calibrated. The PPS includes: Ultrasound transducers (including one exhibiting an unusual output) and a driver for the ultrasound transducers that has calibration and proficiency test functions. Also included with the PPS is a Cavitation Detector to determine the onset of cavitation occurring within the propagation medium. The PPS will be suitable for conducting in-the-field accreditation (proficiency testing and calibration). In order to be accredited it will be important to be able to show traceability of the calibration, the calibration process and qualification of testing staff. The clinical user will benefit from traceability because treatments will be performed more reliably

  1. Power dissipated measurement of an ultrasonic generator in a viscous medium by flowmetric method.

    Science.gov (United States)

    Mancier, Valérie; Leclercq, Didier

    2008-09-01

    A new flowmetric method of the power dissipated by an ultrasound generator in an aqueous medium has been developed in previous works and described in a preceding paper [V. Mancier, D. Leclercq, Ultrasonics Sonochemistry 14 (2007) 99-106]. The works presented here are an enlargement of this method to a high viscosity liquid (glycerol) for which the classical calorimetric measurements are rather difficult. As expected, it is shown that the dissipated power increases with the medium viscosity. It was also found that this flowmetric method gives good results for various quantities of liquid and positioning of the sonotrode in the tank. Moreover, the important variation of viscosity due to the heating of the liquid during experiments does not disturb flow measurements.

  2. Coordinated Power Dispatch of a PMSG based Wind Farm for Output Power Maximizing Considering the Wake Effect and Losses

    DEFF Research Database (Denmark)

    Zhang, Baohua; Hu, Weihao; Hou, Peng

    2016-01-01

    The energy loss in a wind farm (WF) caused by wake interaction between wind turbines (WTs) is quite high, which can be reduced by proper active power dispatch. The electrical loss inside a WF by improper active power and reactive power dispatch is also considerable. In this paper, a coordinated...... active power and reactive power dispatch strategy is proposed for a Permanent magnet synchronous generator (PMSG) based WF, in order to maximize the total output power by reducing the wake effect and losses inside the devices of the WF, including the copper loss and iron loss of PMSGs, losses inside...

  3. A Laser-based Ultrasonic Inspection System to Detect Micro Fatigue Cracks

    International Nuclear Information System (INIS)

    Park, Seung Kyu; Baik, Sung Hoon; Park, Moon Cheol; Lim, Chang Hwan; Cha, Hyung Ki

    2005-01-01

    Laser-based ultrasonic techniques have been established as a viable non-contact alternative to piezoelectric transducers for generating and receiving ultrasound. Laser-based ultrasonic inspection system provides a number of advantages over the conventional generation by piezoelectric transducers, especially a non-contact generation and detection of ultrasonic waves, high spatial scanning resolution, controllable narrow-band and wide-band spectrum, absolute measurements of the moving distance, use of fiber optics, and an ability to operate on curved and rough surfaces and at hard-to-access locations like a nuclear power plant. Ochiai and Miura used the laser-based ultrasound to detect micro fatigue cracks for the inspection of a material degradation in nuclear power plants. This widely applicable laser-based ultrasonic inspection system is comparatively expensive and provides low signal-to-noise ratio to measure ultrasound by using the laser interferometer. Many studies have been carried out to improve the measuring efficiency of the laser interferometer. One of the widely used laser interferometer types to measure the ultrasound is the Confocal Fabry-Perot Interferometer(CFPI). The measurement gain of the CFPI is slightly and continually varied according to the small change of the cavity length and the fluctuations of the measuring laser beam frequency with time. If we continually adjust the voltage of a PZT which is fixed to one of the interferometer mirrors, the optimum working point of the CFPI can be fixed. Though a static stabilizer can fix the gain of the CFPI where the CW laser beam is targeted at one position, it can not be used when the CW laser beam is scanned like a scanning laser source(SLS) technique. A dynamic stabilizer can be used for the scanning ultrasonic inspection system. A robust dynamic stabilizer is needed for an application to the industrial inspection fields. Kromine showed that the SLS technique is effective to detect small fatigue cracks

  4. Study of ultrasonic melt treatment on the quality of horizontal continuously cast Al-1%Si alloy.

    Science.gov (United States)

    Li, Xin-Tao; Li, Ting-Ju; Li, Xi-Meng; Jin, Jun-Ze

    2006-02-01

    The fluctuation of the melt temperature in a tundish was measured during casting and experiments were conducted to investigate the effects of ultrasonic melt treatment on the surface quality and solidification structures of Al-1%Si ingots. The results show that the uniformity of melt temperature was enhanced with the application of ultrasonic melt treatment. When the ultrasonic power is 1,000W, the surface quality was evidently improved and grains of cast ingots were refined. Moreover, EPMA analysis was adopted to study the relationship between the ultrasonic power and boundary segregation of Si element. The result shows that boundary segregation is suppressed with the increase of ultrasonic power and the phenomenon was theoretically interpreted.

  5. Low Power Very High Frequency Switch-Mode Power Supply with 50 V Input and 5 V Output

    DEFF Research Database (Denmark)

    Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.

    2014-01-01

    This paper presents the design of a resonant converter with a switching frequency in the very high frequencyrange (30-300 MHz), a large step down ratio (10 times) and low output power (1 W). Several different invertersand rectifiers are analyzed and compared. The class E inverter and rectifier...... are selected based on complexity andefficiency estimates. Three different power stages are implemented; one with a large input inductor, one with a switch with small capacitances and one with a switch with low on resistance. The power stages are designed with the same specifications and efficiencies from 60...

  6. Pre and post garter spring repositioning ultrasonic inspection of pressure tubes

    International Nuclear Information System (INIS)

    Desimone, C.; Katchadjian, P.; Tacchia, Mauricio

    1997-01-01

    This paper present a description of the ultrasonic cracked hydride blister detections system used for pre and post inspection of pressure tubes during garter spring repositioning in CNE (Embalse Nuclear Power Station). Ultrasonic system setup configuration, transducers characteristics, blister detection head, calibration of parameters, operating procedure, records of ultrasonic inspections and evaluation. (author) [es

  7. A coupled piezoelectric–electromagnetic energy harvesting technique for achieving increased power output through damping matching

    International Nuclear Information System (INIS)

    Challa, Vinod R; Prasad, M G; Fisher, Frank T

    2009-01-01

    Vibration energy harvesting is being pursued as a means to power wireless sensors and ultra-low power autonomous devices. From a design standpoint, matching the electrical damping induced by the energy harvesting mechanism to the mechanical damping in the system is necessary for maximum efficiency. In this work two independent energy harvesting techniques are coupled to provide higher electrical damping within the system. Here the coupled energy harvesting device consists of a primary piezoelectric energy harvesting device to which an electromagnetic component is added to better match the total electrical damping to the mechanical damping in the system. The first coupled device has a resonance frequency of 21.6 Hz and generates a peak power output of ∼332 µW, compared to 257 and 244 µW obtained from the optimized, stand-alone piezoelectric and electromagnetic energy harvesting devices, respectively, resulting in a 30% increase in power output. A theoretical model has been developed which closely agrees with the experimental results. A second coupled device, which utilizes the d 33 piezoelectric mode, shows a 65% increase in power output in comparison to the corresponding stand-alone, single harvesting mode devices. This work illustrates the design considerations and limitations that one must consider to enhance device performance through the coupling of multiple harvesting mechanisms within a single energy harvesting device

  8. Development of ultrasonic instrument 'UT1000 Series'

    International Nuclear Information System (INIS)

    Ogura, Yukio; Ikeda, Toshimichi

    1984-01-01

    The ultrasonic flaw detectors with 'A-scope indication' have been frequently used as the means for confirming the soundness of structures and equipments, but there are problems in their operational, quantifying and recording capabilities. Recently, the digital ultrasonic measuring instrument of touch panel type ''UT 1000 Series'' has been developed, which resolves these problems by a single effort. This measuring instrument is that of portable type, which gives the digital output of measured results in real time only by lightly touching the peak point of an echo on the Brown tube. This instrument contains the rich software for measurement, and can measure the positions and dimensions of defects and the pressure on contact surfaces with high accuracy. 'A-scope indication' is the indication with an oscilloscope taking the intensity of echo and the propagation time of ultrasonic waves on the ordinate and abscissa, respectively. There are three types of the instrument, that is, for detecting defects, for measuring contact surface pressure and for both purposes. The size of the instrument is 240 mm width, 350 mm length and 175 mm height, and the weight is 8.5 kgf. The specification, function and features of the ultrasonic flaw detector, touch panel, gain setter, key board, microcomputer and others are reported. (Kako, I.)

  9. Reproducibility problems of in-service ultrasonic testing results

    International Nuclear Information System (INIS)

    Honcu, E.

    1974-01-01

    The reproducibility of the results of ultrasonic testing is the basic precondition for its successful application in in-service inspection of changes in the quality of components of nuclear power installations. The results of periodic ultrasonic inspections are not satisfactory from the point of view of reproducibility. Regardless, the ultrasonic pulse-type method is suitable for evaluating the quality of most components of nuclear installations and often the sole method which may be recommended for inspection with regard to its technical and economic aspects. (J.B.)

  10. A molecular low power CO/sub 2/ laser with a stabilized output frequency

    Energy Technology Data Exchange (ETDEWEB)

    Plinski, E.F.; Abramski, K.M.; Nowicki, R.; Pienkowski, J.; Rzepka, J.

    1983-01-01

    This laser has a resonator consisting of a spherical mirror with a slope radius of 10 meters and a reflecting diffraction grating (120 lines per millimeter). The use of this grating makes it possible to isolate one of the lines in the 10.4 or 9.4 micrometer bands. A mirror with a central hole 2.5 millimeters in diameter is mounted on a piezoceramic holder designed for tuning the resonator. Frequency stabilization is based on synchronous detection. An auxillary modulating signal injected to a specific section of the piezoceramic holder modulates the level of the laser. The change in the output power may be detected using an uncooled detector (Cd, Hg) Te. The error signal, injected to the holder, tunes the resonator so that it operates in the center of the output power curve.

  11. Optimal Velocity to Achieve Maximum Power Output – Bench Press for Trained Footballers

    OpenAIRE

    Richard Billich; Jakub Štvrtňa; Karel Jelen

    2015-01-01

    Optimal Velocity to Achieve Maximum Power Output – Bench Press for Trained Footballers In today’s world of strength training there are many myths surrounding effective exercising with the least possible negative effect on one’s health. In this experiment we focus on the finding of a relationship between maximum output, used load and the velocity with which the exercise is performed. The main objective is to find the optimal speed of the exercise motion which would allow us to reach the ma...

  12. Determining the Frequency for Load-Independent Output Current in Three-Coil Wireless Power Transfer System

    Directory of Open Access Journals (Sweden)

    Longzhao Sun

    2015-09-01

    Full Text Available Conditions for load-independent output voltage or current in two-coil wireless power transfer (WPT systems have been studied. However, analysis of load-independent output current in three-coil WPT system is still lacking in previous studies. This paper investigates the output current characteristics of a three-coil WPT system against load variations, and determines the operating frequency to achieve a constant output current. First, a three-coil WPT system is modeled by circuit theory, and the analytical expression of the root-mean-square of the output current is derived. By substituting the coupling coefficients, the quality factor, and the resonant frequency of each coil, we propose a method of calculating the frequency for load-independent output current in a three-coil WPT system, which indicates that there are two frequencies that can achieve load-independent output current. Experiments are conducted to validate these analytical results.

  13. Ultrasonic meters in the feedwater flow to recover thermal power in the reactor of nuclear power plant of Laguna Verde U1 and U2; Medidores ultrasonicos en el flujo de agua de alimentacion para recuperar potencia termica en el reactor de la Central Nuclear Laguna Verde U1 and U2

    Energy Technology Data Exchange (ETDEWEB)

    Tijerina S, F. [CFE, Central Laguna Verde, Km. 42.5 Carretera Cardel-Nautla, Veracruz (Mexico)]. e-mail: francisco.tijerina@cfe.gob.mx

    2008-07-01

    The engineers in nuclear power plants BWRs and PWRs based on the development of the ultrasonic technology for the measurement of the mass, volumetric flow, density and temperature in fluids, have applied this technology in two primary targets approved by the NRC: the use for the recovery of thermal power in the reactor and/or to be able to realize an increase of thermal power licensed in a 2% (MUR) by 1OCFR50 Appendix K. The present article mentions the current problem in the measurement of the feedwater flow with Venturi meters, which affects that the thermal balance of reactor BWRs or PWRs this underestimated. One in broad strokes describes the application of the ultrasonic technology for the ultrasonic measurement in the flow of the feedwater system of the reactor and power to recover thermal power of the reactor. One is to the methodology developed in CFE for a calibration of the temperature transmitters of RTD's and the methodology for a calibration of the venturi flow transmitters using ultrasonic measurement. Are show the measurements in the feedwater of reactor of the temperature with RTD's and ultrasonic measurement, as well as the flow with the venturi and the ultrasonic measurement operating the reactor to the 100% of nominal thermal power, before and after the calibration of the temperature transmitters and flow. Finally, is a plan to be able to realize a recovery of thermal power of the reactor, showing as carrying out their estimations. As a result of the application of ultrasonic technology in the feedwater of reactor BWR-5 in Laguna Verde, in the Unit 1 cycle 13 it was recover an equivalent energy to a thermal power of 25 MWt in the reactor and an exit electrical power of 6 M We in the turbogenerator. Also in the Unit 2 cycle 10 it was recover an equivalent energy to a thermal power of 40 MWt in the reactor and an exit electrical power of 16 M We in the turbogenerator. (Author)

  14. Dynamic Takagi-Sugeno Model for the Control of Ultrasonic Motor

    Directory of Open Access Journals (Sweden)

    Shi Jingzhuo

    2011-01-01

    Full Text Available Model of ultrasonic motor is the foundation of the design of ultrasonic motor's speed and position controller. A two-input and one-output dynamic Takagi-Sugeno model of ultrasonic motor driving system is worked out using fuzzy reasoning modeling method in this paper. Many fuzzy reasoning modeling methods are sensitive to the initial values and easy to fall into local minimum, and have a large amount of calculation. In order to overcome these defects, equalized universe method is used in this paper to get clusters centers and obtain fuzzy clustering membership functions, and then, the unknown parameters of the conclusions of fuzzy rules are identified using least-square method. Different experimental data that are tested with different operational conditions are used to examine the validity of the fuzzy model. Comparison between experimental data and calculated data of the model indicates that the model can well describe the nonlinear characteristics among the frequency, amplitude of driving voltage and rotating speed. The proposed fuzzy model can be used to analyze the performance of ultrasonic motor driving system, and also can be used to design the speed and position controller of ultrasonic motor.

  15. Influence of ultrasonic frequency on the regeneration of silica gel by applying high-intensity ultrasound

    International Nuclear Information System (INIS)

    Zhang Weijiang; Yao Ye; Wang Rongshun

    2010-01-01

    Ultrasonic frequency is the key parameter considered in ultrasonic applications. In order to provide a basic knowledge about the influence of ultrasonic frequency on the regeneration of silica gel assisted by power ultrasound, the experiments about silica gel regeneration under the radiation of constant-power (60 W) ultrasound with different frequencies (i.e., 23, 27, and 38 kHz) and that without ultrasound were carried out at different regeneration temperatures (i.e., 35, 45, 55, and 65 deg. C). The experimental results showed that the lower frequency was beneficial for the application of power ultrasound in the regeneration of silica gel. The fact was theoretically explained by the ultrasonic power attenuation model which indicates that the ultrasound of lower frequency will lead to more uniform energy distribution and hence achieve higher efficiency of utilization. Meanwhile, the effect of ultrasonic frequency on silica gel regeneration would be influenced by the regeneration temperature and the moisture ratio in silica gel. As investigated in this study, the effect of ultrasonic frequency on the regeneration would be more significant at the lower regeneration temperature or at the higher moisture ratio in silica gel. In addition, the mean regeneration speed model of silica gel dependent of the regeneration temperature and the ultrasonic frequency was established according to the experimental data.

  16. The left ventricle as a mechanical engine: from Leonardo da Vinci to the echocardiographic assessment of peak power output-to-left ventricular mass.

    Science.gov (United States)

    Dini, Frank L; Guarini, Giacinta; Ballo, Piercarlo; Carluccio, Erberto; Maiello, Maria; Capozza, Paola; Innelli, Pasquale; Rosa, Gian M; Palmiero, Pasquale; Galderisi, Maurizio; Razzolini, Renato; Nodari, Savina

    2013-03-01

    The interpretation of the heart as a mechanical engine dates back to the teachings of Leonardo da Vinci, who was the first to apply the laws of mechanics to the function of the heart. Similar to any mechanical engine, whose performance is proportional to the power generated with respect to weight, the left ventricle can be viewed as a power generator whose performance can be related to left ventricular mass. Stress echocardiography may provide valuable information on the relationship between cardiac performance and recruited left ventricular mass that may be used in distinguishing between adaptive and maladaptive left ventricular remodeling. Peak power output-to-mass, obtained during exercise or pharmacological stress echocardiography, is a measure that reflects the number of watts that are developed by 100 g of left ventricular mass under maximal stimulation. Power output-to-mass may be calculated as left ventricular power output per 100 g of left ventricular mass: 100× left ventricular power output divided by left ventricular mass (W/100 g). A simplified formula to calculate power output-to-mass is as follows: 0.222 × cardiac output (l/min) × mean blood pressure (mmHg)/left ventricular mass (g). When the integrity of myocardial structure is compromised, a mismatch becomes apparent between maximal cardiac power output and left ventricular mass; when this occurs, a reduction of the peak power output-to-mass index is observed.

  17. Leg joint power output during progressive resistance FES-LCE cycling in SCI subjects: developing an index of fatigue

    Directory of Open Access Journals (Sweden)

    Faghri Pouran D

    2008-04-01

    Full Text Available Abstract Background The purpose of this study was to investigate the biomechanics of the hip, knee and ankle during a progressive resistance cycling protocol in an effort to detect and measure the presence of muscle fatigue. It was hypothesized that knee power output can be used as an indicator of fatigue in order to assess the cycling performance of SCI subjects. Methods Six spinal cord injured subjects (2 incomplete, 4 complete between the ages of twenty and fifty years old and possessing either a complete or incomplete spinal cord injury at or below the fourth cervical vertebra participated in this study. Kinematic data and pedal forces were recorded during cycling at increasing levels of resistance. Ankle, knee and hip power outputs and resultant pedal force were calculated. Ergometer cadence and muscle stimulation intensity were also recorded. Results The main findings of this study were: (a ankle and knee power outputs decreased, whereas hip power output increased with increasing resistance, (b cadence, stimulation intensity and resultant pedal force in that combined order were significant predictors of knee power output and (c knowing the value of these combined predictors at 10 rpm, an index of fatigue can be developed, quantitatively expressing the power capacity of the knee joint with respect to a baseline power level defined as fatigue. Conclusion An index of fatigue was successfully developed, proportionalizing knee power capacity during cycling to a predetermined value of fatigue. The fatigue index value at 0/8th kp, measured 90 seconds into active, unassisted pedaling was 1.6. This indicates initial power capacity at the knee to be 1.6 times greater than fatigue. The fatigue index decreased to 1.1 at 2/8th kp, representing approximately a 30% decrease in the knee's power capacity within a 4 minute timespan. These findings suggest that the present cycling protocol is not sufficient for a rider to gain the benefits of FES and thus

  18. Leg joint power output during progressive resistance FES-LCE cycling in SCI subjects: developing an index of fatigue.

    Science.gov (United States)

    Haapala, Stephenie A; Faghri, Pouran D; Adams, Douglas J

    2008-04-26

    The purpose of this study was to investigate the biomechanics of the hip, knee and ankle during a progressive resistance cycling protocol in an effort to detect and measure the presence of muscle fatigue. It was hypothesized that knee power output can be used as an indicator of fatigue in order to assess the cycling performance of SCI subjects. Six spinal cord injured subjects (2 incomplete, 4 complete) between the ages of twenty and fifty years old and possessing either a complete or incomplete spinal cord injury at or below the fourth cervical vertebra participated in this study. Kinematic data and pedal forces were recorded during cycling at increasing levels of resistance. Ankle, knee and hip power outputs and resultant pedal force were calculated. Ergometer cadence and muscle stimulation intensity were also recorded. The main findings of this study were: (a) ankle and knee power outputs decreased, whereas hip power output increased with increasing resistance, (b) cadence, stimulation intensity and resultant pedal force in that combined order were significant predictors of knee power output and (c) knowing the value of these combined predictors at 10 rpm, an index of fatigue can be developed, quantitatively expressing the power capacity of the knee joint with respect to a baseline power level defined as fatigue. An index of fatigue was successfully developed, proportionalizing knee power capacity during cycling to a predetermined value of fatigue. The fatigue index value at 0/8th kp, measured 90 seconds into active, unassisted pedaling was 1.6. This indicates initial power capacity at the knee to be 1.6 times greater than fatigue. The fatigue index decreased to 1.1 at 2/8th kp, representing approximately a 30% decrease in the knee's power capacity within a 4 minute timespan. These findings suggest that the present cycling protocol is not sufficient for a rider to gain the benefits of FES and thus raises speculation as to whether or not progressive resistance

  19. Change in power output across a high-repetition set of bench throws and jump squats in highly trained athletes.

    Science.gov (United States)

    Baker, Daniel G; Newton, Robert U

    2007-11-01

    Athletes experienced in maximal-power and power-endurance training performed 1 set of 2 common power training exercises in an effort to determine the effects of moderately high repetitions upon power output levels throughout the set. Twenty-four and 15 athletes, respectively, performed a set of 10 repetitions in both the bench throw (BT P60) and jump squat exercise (JS P60) with a resistance of 60 kg. For both exercises, power output was highest on either the second (JS P60) or the third repetition (BT P60) and was then maintained until the fifth repetition. Significant declines in power output occurred from the sixth repetition onwards until the 10th repetition (11.2% for BT P60 and 5% for JS P60 by the 10th repetition). These findings suggest that athletes attempting to increase maximal power limit their repetitions to 2 to 5 when using resistances of 35 to 45% 1RM in these exercises.

  20. Effect of decision making on ultrasonic examination performance

    International Nuclear Information System (INIS)

    Harris, D.H.

    1992-05-01

    A decision aid was developed to overcome examiner limitations in information processing and decision making during ultrasonic examinations. The aid provided a means of noting signal characteristics as they were observed during the examination, and of presenting them simultaneously for decision making. The aid also served as a way of providing detailed feedback on examination performance during training. The aid was incorporated into worksheets used for the conduct of practice examinations during ultrasonic examination training. To support the introduction and use of the decision aid, one hour of supplementary training was inserted in an existing 64-hour training course on ultrasonic detection of defects. This study represented a modest step in improving the performance of ultrasonic examinations in nuclear power plants. Findings indicated that aided decision making supported by limited training can significantly improve ultrasonic detection performance

  1. Ultrasonic flow-meter test in sodium

    International Nuclear Information System (INIS)

    Ishii, Y.; Uno, O.; Kamei, M.

    1978-01-01

    As a part of the R and D programme for the prototype fast breeder reactor MONJU, an ultrasonic flow-meter (USFM) test is being carried out in sodium in the O-Arai Engineering Center of PNC. Prior to the present test, an in-water test was done at the manufacturer's as a preliminary investigation. The results reported here are the results up to the present. Calibration tests using the actual fluid were conducted on a 12-inch ultrasonic flow-meter with guide rods fabricated for sodium flow measurement. The test conditions in sodium were a temperature of 200 approximately 400 0 C and flow-rates of 0 approximately 6m/s. The main results are: (1) The linearity of output signal was good and accuracy was within 1%; (2) The alternating type of the USFM was much better than the fixed type in temperature change; (3) 2MHz of transducer frequency was better than 3MHz in sodium; (4) The S/N ratio of the ultrasonic signal and the length/diameter effect in a wide range in sodium surpassed the in-water test. (author)

  2. Output power fluctuations due to different weights of macro particles used in particle-in-cell simulations of Cerenkov devices

    International Nuclear Information System (INIS)

    Bao, Rong; Li, Yongdong; Liu, Chunliang; Wang, Hongguang

    2016-01-01

    The output power fluctuations caused by weights of macro particles used in particle-in-cell (PIC) simulations of a backward wave oscillator and a travelling wave tube are statistically analyzed. It is found that the velocities of electrons passed a specific slow-wave structure form a specific electron velocity distribution. The electron velocity distribution obtained in PIC simulation with a relative small weight of macro particles is considered as an initial distribution. By analyzing this initial distribution with a statistical method, the estimations of the output power fluctuations caused by different weights of macro particles are obtained. The statistical method is verified by comparing the estimations with the simulation results. The fluctuations become stronger with increasing weight of macro particles, which can also be determined reversely from estimations of the output power fluctuations. With the weights of macro particles optimized by the statistical method, the output power fluctuations in PIC simulations are relatively small and acceptable.

  3. Input-output model of regional environmental and economic impacts of nuclear power plants

    International Nuclear Information System (INIS)

    Johnson, M.H.; Bennett, J.T.

    1979-01-01

    The costs of delayed licensing of nuclear power plants calls for a more-comprehensive method of quantifying the economic and environmental impacts on a region. A traditional input-output (I-O) analysis approach is extended to assess the effects of changes in output, income, employment, pollution, water consumption, and the costs and revenues of local government disaggregated among 23 industry sectors during the construction and operating phases. Unlike earlier studies, this model uses nonlinear environmental interactions and specifies environmental feedbacks to the economic sector. 20 references

  4. Effect of low dose, short-term creatine supplementation on muscle power output in elite youth soccer players.

    Science.gov (United States)

    Yáñez-Silva, Aquiles; Buzzachera, Cosme F; Piçarro, Ivan Da C; Januario, Renata S B; Ferreira, Luis H B; McAnulty, Steven R; Utter, Alan C; Souza-Junior, Tacito P

    2017-01-01

    To determine the effects of a low dose, short-term Creatine monohydrate (Cr) supplementation (0.03 g.kg.d -1 during 14 d) on muscle power output in elite youth soccer players. Using a two-group matched, double blind, placebo-controlled design, nineteen male soccer players (mean age = 17.0 ± 0.5 years) were randomly assigned to either Cr ( N  = 9) or placebo ( N  = 10) group. Before and after supplementation, participants performed a 30s Wingate Anaerobic Test (WAnT) to assess peak power output (PPO), mean power output (MPO), fatigue index (FI), and total work. There were significant increases in both PPO and MPO after the Cr supplementation period ( P  ≤ 0.05) but not the placebo period. There were also significant increases in total work, but not FI, after the Cr supplementation and placebo periods ( P  ≤ 0.05). Notably, there were differences in total work between the Cr and placebo groups after ( P  ≤ 0.05) but not before the 14 d supplementation period. There is substantial evidence to indicate that a low-dose, short-term oral Cr supplementation beneficially affected muscle power output in elite youth soccer players.

  5. Evaluation of Effect by Internal Flow on Ultrasonic Testing Flaw Sizing in Piping

    International Nuclear Information System (INIS)

    Lee, Jeong Seok; Yoon, Byung Sik; Kim, Yong Sik

    2013-01-01

    In this study, the ultrasonic amplitude difference between air filled and water filled piping in nuclear power plant is compared by modeling approach. In this study, ultrasonic amplitude differences between air and water filled pipe are evaluated by modeling approach. Consequently, we propose the following results. The ultrasonic amplitude difference between air and water filled condition is measured by lower than 1 dB in modeling calculation. The flaw length sizing error between air and water filled condition shows same results based on 12 dB drop method even thought the amplitude difference is 1 dB. Most of the piping welds in nuclear power plants are inspected periodically using ultrasonic techniques to detect service-induced flaws such as IGSCC cracking. The inspection results provide information such as location, maximum amplitude response, ultrasonic length, height and finally the nature or flaw pattern. The founded flaw in ultrasonic inspection is accepted or rejected based on these information. Specially, the amplitude of flaw response is very important to estimate the flaw size. Currently the ultrasonic inspections in nuclear power plant components are performed by specific inspection procedure which describing inspection technique include inspection system, calibration methodology and flaw characterizing methodology. To perform ultrasonic inspection during in-service inspection, reference gain should be established before starting ultrasonic inspection by requirement of ASME code. This reference gain used as basic criteria to evaluate flaw sizing. Sometimes, a little difference in establishing reference gain between calibration and field condition can lead to deviation in flaw sizing. Due to this difference, the inspection result may cause flaw sizing error

  6. STADUS - Ultrasonic data acquisition and processing system

    International Nuclear Information System (INIS)

    Saglio, Robert; Birac, A.M.; Frappier, J.C.

    1982-05-01

    The CEA (Commissariat a l'Energie Atomique) has developed a system for the acquisition and analysis of data recorded during ultrasonic testing. Initially this system was designed and built for the needs of in-service inspection of PWR type power reactors. It is in far wider use today for miscellaneous automatic ultrasonic inspection procedures. This system records, in digital form, the ultrasonic data supplied by the transducers (maximum 16 simultaneous channels), and the geometric coordinates defining the position of the inspection tool. Based on these data, which are recorded on floppy disk, this system helps to display data in the form of A SCAN, B SCAN and C SCAN images. In addition, processing programs of data transfer from the STADUS floppy disks have been developed and inserted on computers more powerful than the one used in the STADUS system. These programs serve to obtain different fault charts on an adjustable scale, as well as listings concerning the defect positions and dimensions [fr

  7. Control of molecular weight distribution in synthesis of poly(2-hydroxyethyl methacrylate) using ultrasonic irradiation.

    Science.gov (United States)

    Kubo, Masaki; Kondo, Takayuki; Matsui, Hideki; Shibasaki-Kitakawa, Naomi; Yonemoto, Toshikuni

    2018-01-01

    Poly(2-hydroxyethyl methacrylate) (PHEMA) was synthesized using ultrasonic irradiation without any chemical initiator. The effect of the ultrasonic power intensity on the time course of the conversion to polymer, the number average molecular weight, and the polydispersity were investigated in order to synthesize a polymer with a low molecular weight distribution (i.e., low polydispersity). The conversion to polymer increased with time. A higher ultrasonic power intensity resulted in a faster reaction rate. The number average molecular weight increased during the early stage of the reaction and then gradually decreased with time. A higher ultrasonic intensity resulted in a faster degradation rate of the polymer. The polydispersity decreased with time. This was because the degradation rate of a polymer with a higher molecular weight was faster than that of a polymer with a lower molecular weight. A polydispersity below 1.3 was obtained under ultrasonic irradiation. By changing the ultrasonic power intensity during the reaction, the number average molecular weight can be controlled while maintaining low polydispersity. When the ultrasonic irradiation was halted, the reactions stopped and the number average molecular weight and polydispersity did not change. On the basis of the experimental results, a kinetic model for synthesis of PHEMA under ultrasonic irradiation was constructed considering both polymerization and polymer degradation. The kinetic model was in good agreement with the experimental results for the time courses of the conversion to polymer, the number average molecular weight, and the polydispersity for various ultrasonic power intensities. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Ultrasonic hyperactivation of cellulase immobilized on magnetic nanoparticles.

    Science.gov (United States)

    Ladole, Mayur Ramrao; Mevada, Jayesh Sevantilal; Pandit, Aniruddha Bhalchandra

    2017-09-01

    In the present work, effect of low power, low frequency ultrasound on cellulase immobilized magnetic nanoparticles (cellulase@MNPs) was studied. To gain maximum activity recovery in cellulase@MNPs various parameters viz. ratio of MNPs:cellulase, concentration of glutaraldehyde and cross-linking time were optimized. The influence of ultrasonic power on cellulase@MNPs was studied. Under ultrasonic conditions at 24kHz, 6W power, and 6min of incubation time there was almost 3.6 fold increased in the catalytic activity of immobilized cellulase over the control. Results also indicated that there was improvement in pH and temperature stability of cellulase@MNPs. Furthermore, thermal deactivation energy required was more in cellulase@MNPs than that of the free cellulase. Secondary structural analysis revealed that there were conformational changes in free cellulase and cellulase@MNPs before and after sonication which might be responsible for enhanced activity after ultrasonication. Finally, the influence of ultrasound and cellulase@MNPs for biomass hydrolysis was studied. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. SOLAR PHOTOVOLTAIC OUTPUT POWER FORECASTING USING BACK PROPAGATION NEURAL NETWORK

    Directory of Open Access Journals (Sweden)

    B. Jency Paulin

    2016-01-01

    Full Text Available Solar Energy is an important renewable and unlimited source of energy. Solar photovoltaic power forecasting, is an estimation of the expected power production, that help the grid operators to better manage the electric balance between power demand and supply. Neural network is a computational model that can predict new outcomes from past trends. The artificial neural network is used for photovoltaic plant energy forecasting. The output power for solar photovoltaic cell is predicted on hourly basis. In historical dataset collection process, two dataset was collected and used for analysis. The dataset was provided with three independent attributes and one dependent attributes. The implementation of Artificial Neural Network structure is done by Multilayer Perceptron (MLP and training procedure for neural network is done by error Back Propagation (BP. In order to train and test the neural network, the datasets are divided in the ratio 70:30. The accuracy of prediction can be done by using various error measurement criteria and the performance of neural network is to be noted.

  10. Human power output during repeated sprint cycle exercise: the influence of thermal stress

    NARCIS (Netherlands)

    Ball, D.; Burrows, C.; Sargeant, A.J.

    1999-01-01

    Thermal stress is known to impair endurance capacity during moderate prolonged exercise. However, there is relatively little available information concerning the effects of thermal stress on the performance of high-intensity short-duration exercise. The present experiment examined human power output

  11. 270 nm Pseudomorphic Ultraviolet Light-Emitting Diodes with Over 60 mW Continuous Wave Output Power

    Science.gov (United States)

    Grandusky, James R.; Chen, Jianfeng; Gibb, Shawn R.; Mendrick, Mark C.; Moe, Craig G.; Rodak, Lee; Garrett, Gregory A.; Wraback, Michael; Schowalter, Leo J.

    2013-03-01

    In this letter, the achievement of over 60 mW output power from pseudomorphic ultraviolet light-emitting diodes in continuous wave operation is reported. Die thinning and encapsulation improved the photon extraction efficiency to over 15%. Improved thermal management and a high characteristic temperature resulted in a low thermal rolloff up to 300 mA injection current with an output power of 67 mW, an external quantum efficiency (EQE) of 4.9%, and a wall plug efficiency (WPE) of 2.5% for a single-chip device emitting at 271 nm in continuous wave operation.

  12. Enhanced Output Power of PZT Nanogenerator by Controlling Surface Morphology of Electrode.

    Science.gov (United States)

    Jung, Woo-Suk; Lee, Won-Hee; Ju, Byeong-Kwon; Yoon, Seok-Jin; Kang, Chong-Yun

    2015-11-01

    Piezoelectric power generation using Pb(Zr,Ti)O3(PZT) nanowires grown on Nb-doped SrTiO3(nb:STO) substrate has been demonstrated. The epitaxial PZT nanowires prepared by a hydrothermal method, with a diameter and length of approximately 300 nm and 7 μm, respecively, were vertically aligned on the substrate. An embossed Au top electrode was applied to maximize the effective power generation area for non-uniform PZT nanowires. The PZT nanogenerator produced output power density of 0.56 μW/cm2 with a voltage of 0.9 V and current of 75 nA. This research suggests that the morphology control of top electrode can be useful to improve the efficiency of piezoelectric power generation.

  13. Output Power Limitations and Improvements in Passively Mode Locked GaAs/AlGaAs Quantum Well Lasers.

    Science.gov (United States)

    Tandoi, Giuseppe; Ironside, Charles N; Marsh, John H; Bryce, A Catrina

    2012-03-01

    We report a novel approach for increasing the output power in passively mode locked semiconductor lasers. Our approach uses epitaxial structures with an optical trap in the bottom cladding that enlarges the vertical mode size to scale the pulse saturation energy. With this approach we demonstrate a very high peak power of 9.8 W per facet, at a repetition rate of 6.8 GHz and with pulse duration of 0.71 ps. In particular, we compare two GaAs/AlGaAs epilayer designs, a double quantum well design operating at 830 nm and a single quantum well design operating at 795 nm, with vertical mode sizes of 0.5 and 0.75 μm, respectively. We show that a larger mode size not only shifts the mode locking regime of operation towards higher powers, but also produces other improvements in respect of two main failure mechanisms that limit the output power: the catastrophic optical mirror damage and the catastrophic optical saturable absorber damage. For the 830 nm material structure, we also investigate the effect of non-absorbing mirrors on output power and mode locked operation of colliding pulse mode locked lasers.

  14. Development of an ultrasonic process for soil remediation

    International Nuclear Information System (INIS)

    Wu, J.M.; Huang, H.S.; Livengood, C.D.

    1995-01-01

    An ultrasonic process for the detoxification of carbon tetrachloride- (CCl 4 - ) contaminated soil was investigated in the laboratory by using a batch irradiation reactor equipped with a 600-W ultrasonic power supply operated at a frequency of 20 kHz. Key parameters studied included soil characteristics, irradiation time, CCl 4 concentration, steady-state operating temperature, applied ultrasonic-wave energy, and the ratio of soil to water in the system. The results of the experiments showed that (1) residual CCl 4 concentrations could be decreased with longer irradiation periods and (2) detoxification efficiency was proportional to steady-state operating temperature and applied ultrasonic-wave energy. The characteristics of the contaminated soil were found to be an important factor in the design of an ultrasonic detoxification system. A soil-phase CCl 4 concentration below 1 ppm (initial concentration of 56 ppm) was achieved through this process, indicating that the application of ultrasonic irradiation is feasible and effective in the detoxification of soil contaminated by organic compounds. On the basis of the experimental results, a schematic of a full-scale ultrasonic soil-detoxification system was developed. Improvements to this novel process are discussed

  15. Output Power Control of Wind Turbine Generator by Pitch Angle Control using Minimum Variance Control

    Science.gov (United States)

    Senjyu, Tomonobu; Sakamoto, Ryosei; Urasaki, Naomitsu; Higa, Hiroki; Uezato, Katsumi; Funabashi, Toshihisa

    In recent years, there have been problems such as exhaustion of fossil fuels, e. g., coal and oil, and environmental pollution resulting from consumption. Effective utilization of renewable energies such as wind energy is expected instead of the fossil fuel. Wind energy is not constant and windmill output is proportional to the cube of wind speed, which cause the generated power of wind turbine generators (WTGs) to fluctuate. In order to reduce fluctuating components, there is a method to control pitch angle of blades of the windmill. In this paper, output power leveling of wind turbine generator by pitch angle control using an adaptive control is proposed. A self-tuning regulator is used in adaptive control. The control input is determined by the minimum variance control. It is possible to compensate control input to alleviate generating power fluctuation with using proposed controller. The simulation results with using actual detailed model for wind power system show effectiveness of the proposed controller.

  16. An advanced system for automated ultrasonic testing

    International Nuclear Information System (INIS)

    Dressler, K.

    1989-01-01

    As the main component of the AUP system, an ALOK ultrasonic unit has been chosen as it allows for testing of large component areas both search for defects and description of defect geometries. All data required for fault analysis can be obtained by one measuring run. For inspection of primary circuit components in nuclear power stations, the manipulator control and the ultrasonic probe are installed behind the first sufficient shielding. (orig./HP) [de

  17. Modeling of ultrasonic processes utilizing a generic software framework

    Science.gov (United States)

    Bruns, P.; Twiefel, J.; Wallaschek, J.

    2017-06-01

    Modeling of ultrasonic processes is typically characterized by a high degree of complexity. Different domains and size scales must be regarded, so that it is rather difficult to build up a single detailed overall model. Developing partial models is a common approach to overcome this difficulty. In this paper a generic but simple software framework is presented which allows to coupe arbitrary partial models by slave modules with well-defined interfaces and a master module for coordination. Two examples are given to present the developed framework. The first one is the parameterization of a load model for ultrasonically-induced cavitation. The piezoelectric oscillator, its mounting, and the process load are described individually by partial models. These partial models then are coupled using the framework. The load model is composed of spring-damper-elements which are parameterized by experimental results. In the second example, the ideal mounting position for an oscillator utilized in ultrasonic assisted machining of stone is determined. Partial models for the ultrasonic oscillator, its mounting, the simplified contact process, and the workpiece’s material characteristics are presented. For both applications input and output variables are defined to meet the requirements of the framework’s interface.

  18. Minimization of the hole overcut and cylindricity errors during rotary ultrasonic drilling of Ti-6Al-4V

    Science.gov (United States)

    Nasr, M.; Anwar, S.; El-Tamimi, A.; Pervaiz, S.

    2018-04-01

    Titanium and its alloys e.g. Ti6Al4V have widespread applications in aerospace, automotive and medical industry. At the same time titanium and its alloys are regarded as difficult to machine materials due to their high strength and low thermal conductivity. Significant efforts have been dispensed to improve the accuracy of the machining processes for Ti6Al4V. The current study present the use of the rotary ultrasonic drilling (RUD) process for machining high quality holes in Ti6Al4V. The study takes into account the effects of the main RUD input parameters including spindle speed, ultrasonic power, feed rate and tool diameter on the key output responses related to the accuracy of the drilled holes including cylindricity and overcut errors. Analysis of variance (ANOVA) was employed to study the influence of the input parameters on cylindricity and overcut error. Later, regression models were developed to find the optimal set of input parameters to minimize the cylindricity and overcut errors.

  19. PI and Fuzzy Control Strategies for High Voltage Output DC-DC Boost Power Converter - Hardware Implementation and Analysis

    DEFF Research Database (Denmark)

    Padmanaban, Sanjeevi Kumar; Blaabjerg, Frede; Siano, Pierluigi

    2016-01-01

    This paper presents the control strategies by Proportional-Integral (P-I) and Fuzzy Logic (FL) for a DC-DC boost power converter for high output voltage configuration. Standard DC-DC converters are traditionally used for high voltage direct current (HVDC) power transmission systems. But, lack its...... converter with inbuilt voltage-lift technique and overcome the aforementioned deficiencies. Further, the control strategy is adapted based on proportional-integral (P-I) and fuzzy logic, closed-loop controller to regulate the outputs and ensure the performances. Complete hardware prototype of EHV converter...... performances in terms of efficiency, reduced transfer gain and increased cost with sensor units. Moreover, the internal self-parasitic components reduce the output voltage and efficiency of classical high voltage converters (HVC). This investigation focused on extra high-voltage (EHV) DC-DC boost power...

  20. Dispersion compensated mid-infrared quantum cascade laser frequency comb with high power output

    Directory of Open Access Journals (Sweden)

    Q. Y. Lu

    2017-04-01

    Full Text Available Chromatic dispersion control plays an underlying role in optoelectronics and spectroscopy owing to its enhancement to nonlinear interactions by reducing the phase mismatching. This is particularly important to optical frequency combs based on quantum cascade lasers which require negligible dispersions for efficient mode locking of the dispersed modes into equally spaced comb modes. Here, we demonstrated a dispersion compensated mid-IR quantum cascade laser frequency comb with high power output at room temperature. A low-loss dispersive mirror has been engineered to compensate the device’s dispersion residue for frequency comb generation. Narrow intermode beating linewidths of 40 Hz in the comb-working currents were identified with a high power output of 460 mW and a broad spectral coverage of 80 cm-1. This dispersion compensation technique will enable fast spectroscopy and high-resolution metrology based on QCL combs with controlled dispersion and suppressed noise.

  1. Residual gravimetric method to measure nebulizer output.

    Science.gov (United States)

    Vecellio None, Laurent; Grimbert, Daniel; Bordenave, Joelle; Benoit, Guy; Furet, Yves; Fauroux, Brigitte; Boissinot, Eric; De Monte, Michele; Lemarié, Etienne; Diot, Patrice

    2004-01-01

    The aim of this study was to assess a residual gravimetric method based on weighing dry filters to measure the aerosol output of nebulizers. This residual gravimetric method was compared to assay methods based on spectrophotometric measurement of terbutaline (Bricanyl, Astra Zeneca, France), high-performance liquid chromatography (HPLC) measurement of tobramycin (Tobi, Chiron, U.S.A.), and electrochemical measurements of NaF (as defined by the European standard). Two breath-enhanced jet nebulizers, one standard jet nebulizer, and one ultrasonic nebulizer were tested. Output produced by the residual gravimetric method was calculated by weighing the filters both before and after aerosol collection and by filter drying corrected by the proportion of drug contained in total solute mass. Output produced by the electrochemical, spectrophotometric, and HPLC methods was determined after assaying the drug extraction filter. The results demonstrated a strong correlation between the residual gravimetric method (x axis) and assay methods (y axis) in terms of drug mass output (y = 1.00 x -0.02, r(2) = 0.99, n = 27). We conclude that a residual gravimetric method based on dry filters, when validated for a particular agent, is an accurate way of measuring aerosol output.

  2. Maximum power output and load matching of a phosphoric acid fuel cell-thermoelectric generator hybrid system

    Science.gov (United States)

    Chen, Xiaohang; Wang, Yuan; Cai, Ling; Zhou, Yinghui

    2015-10-01

    Based on the current models of phosphoric acid fuel cells (PAFCs) and thermoelectric generators (TGs), a new hybrid system is proposed, in which the effects of multi-irreversibilities resulting from the activation, concentration, and ohmic overpotentials in the PAFC, Joule heat and heat leak in the TG, finite-rate heat transfer between the TG and the heat reservoirs, and heat leak from the PAFC to the environment are taken into account. Expressions for the power output and efficiency of the PAFC, TG, and hybrid system are analytically derived and directly used to discuss the performance characteristics of the hybrid system. The optimal relationship between the electric currents in the PAFC and TG is obtained. The maximum power output is numerically calculated. It is found that the maximum power output density of the hybrid system will increase about 150 Wm-2, compared with that of a single PAFC. The problem how to optimally match the load resistances of two subsystems is discussed. Some significant results for practical hybrid systems are obtained.

  3. Inverter communications using output signal

    Science.gov (United States)

    Chapman, Patrick L.

    2017-02-07

    Technologies for communicating information from an inverter configured for the conversion of direct current (DC) power generated from an alternative source to alternating current (AC) power are disclosed. The technologies include determining information to be transmitted from the inverter over a power line cable connected to the inverter and controlling the operation of an output converter of the inverter as a function of the information to be transmitted to cause the output converter to generate an output waveform having the information modulated thereon.

  4. Degradation of acephate using combined ultrasonic and ozonation method

    Directory of Open Access Journals (Sweden)

    Bin Wang

    2015-07-01

    Full Text Available The degradation of acephate in aqueous solutions was investigated with the ultrasonic and ozonation methods, as well as a combination of both. An experimental facility was designed and operation parameters such as the ultrasonic power, temperature, and gas flow rate were strictly controlled at constant levels. The frequency of the ultrasonic wave was 160 kHz. The ultraviolet-visible (UV-Vis spectroscopic and Raman spectroscopic techniques were used in the experiment. The UV-Vis spectroscopic results show that ultrasonication and ozonation have a synergistic effect in the combined system. The degradation efficiency of acephate increases from 60.6% to 87.6% after the solution is irradiated by a 160 kHz ultrasonic wave for 60 min in the ozonation process, and it is higher with the combined method than the sum of the separated ultrasonic and ozonation methods. Raman spectra studies show that degradation via the combined ultrasonic/ozonation method is more thorough than photocatalysis. The oxidability of nitrogen atoms is promoted under ultrasonic waves. Changes of the inorganic ions and degradation pathway during the degradation process were investigated in this study. Most final products are innocuous to the environment.

  5. Evaluation of Manual Ultrasonic Examinations Applied to Detect Flaws in Primary System Dissimilar Metal Welds at North Anna Power Station

    International Nuclear Information System (INIS)

    Anderson, Michael T.; Diaz, Aaron A.; Doctor, Steven R.

    2012-01-01

    During a recent inservice inspection (ISI) of a dissimilar metal weld (DMW) in an inlet (hot leg) steam generator nozzle at North Anna Power Station Unit 1, several axially oriented flaws went undetected by the licensee's manual ultrasonic testing (UT) technique. The flaws were subsequently detected as a result of outside diameter (OD) surface machining in preparation for a full structural weld overlay. The machining operation uncovered the existence of two through-wall flaws, based on the observance of primary water leaking from the DMW. Further ultrasonic tests were then performed, and a total of five axially oriented flaws, classified as primary water stress corrosion cracking (PWSCC), were detected in varied locations around the weld circumference.

  6. The effect of pole's height on the output performance of solar power ...

    African Journals Online (AJOL)

    Solar energy is a renewable (non-conventional) source of energy supply that has been used as a reliable energy source in view of its economic importance and its wide range of applications. In this study the effect of pole's height on the output performance of solar power system has been investigated. A solar panel of 45 ...

  7. Arrival-Time Detection and Ultrasonic Flow-Meter Applications

    International Nuclear Information System (INIS)

    Willatzen, Morten; Soendergaard, Peter; Latino, Carl; Voss, Frands; Andersen, Niels Lervad; Brokate, Martin; Bounaim, Aicha

    2006-01-01

    The Danfoss problem on ultrasonic flow measurement has been separated into three parts each handled by a subgroup of the authors listed above. The first subgroup deals with a presentation of modelling equations describing the physics of ultrasonic flow meters employing reciprocal ultrasonic transducer systems. The mathematical model presented allows the electrical output signal to be determined corresponding to any time-dependent electrical input signal. The transducers modelled consist of a piezoceramic material layer and a passive acoustic matching layer. The second subgroup analyzes the possibility of coding the input signal so as to simplify arrival-time detection by re.nding the coded input sequence in the received signal. The narrow-band nature of the transducers makes this problem non-trivial but suggestions for improvement are proposed. The analysis given is based on traditional autoand cross-correlation techniques. The third subgroup attempts to improve existing correlation methods in determining arrival-time detection of signals. A mathematical formulation of the problem is given and the application to a set of real signals provided by Danfoss A/S is performed with good results

  8. Relationships among peak power output, peak bar velocity, and mechanomyographic amplitude during the free-weight bench press exercise.

    Science.gov (United States)

    Stock, Matt S; Beck, Travis W; Defreitas, Jason M; Dillon, Michael A

    2010-10-01

    The purpose of this study was to examine the relationships among mechanomyographic (MMG) amplitude, power output, and bar velocity during the free-weight bench press exercise. Twenty-one resistance-trained men [one-repetition maximum (1-RM) bench press = 125.4+18.4 kg] performed bench press muscle actions as explosively as possible from 10% to 90% of the 1-RM while peak power output and peak bar velocity were assessed with a TENDO Weightlifting Analyzer. During each muscle action, surface MMG signals were detected from the right and left pectoralis major and triceps brachii, and the concentric portion of the range of motion was selected for analysis. Results indicated that power output increased from 10% to 50% 1-RM, followed by decreases from 50% to 90% 1-RM, but MMG amplitude for each of the muscles increased from 10 to 80% 1-RM. The results of this study indicate that during the free-weight bench press exercise, MMG amplitude was not related to power output, but was inversely related to bar velocity and directly related to the external load being lifted. In future research, coaches and sport scientists may be able to estimate force/torque production from individual muscles during multi-joint, dynamic constant external resistance muscle actions.

  9. Bi-directional ultrasonic wave coupling to FBGs in continuously bonded optical fiber sensing.

    Science.gov (United States)

    Wee, Junghyun; Hackney, Drew; Bradford, Philip; Peters, Kara

    2017-09-01

    Fiber Bragg grating (FBG) sensors are typically spot-bonded onto the surface of a structure to detect ultrasonic waves in laboratory demonstrations. However, to protect the rest of the optical fiber from any environmental damage during real applications, bonding the entire length of fiber, called continuous bonding, is commonly done. In this paper, we investigate the impact of continuously bonding FBGs on the measured Lamb wave signal. In theory, the ultrasonic wave signal can bi-directionally transfer between the optical fiber and the plate at any adhered location, which could potentially produce output signal distortion for the continuous bonding case. Therefore, an experiment is performed to investigate the plate-to-fiber and fiber-to-plate signal transfer, from which the signal coupling coefficient of each case is theoretically estimated based on the experimental data. We demonstrate that the two coupling coefficients are comparable, with the plate-to-fiber case approximately 19% larger than the fiber-to-plate case. Finally, the signal waveform and arrival time of the output FBG responses are compared between the continuous and spot bonding cases. The results indicate that the resulting Lamb wave signal output is only that directly detected at the FBG location; however, a slight difference in signal waveform is observed between the two bonding configurations. This paper demonstrates the practicality of using continuously bonded FBGs for ultrasonic wave detection in structural health monitoring (SHM) applications.

  10. W5″ Test: A simple method for measuring mean power output in the bench press exercise.

    Science.gov (United States)

    Tous-Fajardo, Julio; Moras, Gerard; Rodríguez-Jiménez, Sergio; Gonzalo-Skok, Oliver; Busquets, Albert; Mujika, Iñigo

    2016-11-01

    The aims of the present study were to assess the validity and reliability of a novel simple test [Five Seconds Power Test (W5″ Test)] for estimating the mean power output during the bench press exercise at different loads, and its sensitivity to detect training-induced changes. Thirty trained young men completed as many repetitions as possible in a time of ≈5 s at 25%, 45%, 65% and 85% of one-repetition maximum (1RM) in two test sessions separated by four days. The number of repetitions, linear displacement of the bar and time needed to complete the test were recorded by two independent testers, and a linear encoder was used as the criterion measure. For each load, the mean power output was calculated in the W5″ Test as mechanical work per time unit and compared with that obtained from the linear encoder. Subsequently, 20 additional subjects (10 training group vs. 10 control group) were assessed before and after completing a seven-week training programme designed to improve maximal power. Results showed that both assessment methods correlated highly in estimating mean power output at different loads (r range: 0.86-0.94; p bench press exercise in subjects who have previous resistance training experience.

  11. Ultrasonic process for detoxification of groundwater

    International Nuclear Information System (INIS)

    Wu, Jiann M.; Huang, H.S.; Livengood, C.D.

    1991-01-01

    In this paper, we present the results of an investigation of the ultrasonic irradiation of carbon tetrachloride at various pH values, temperatures, and power intensities. Kinetic data and selected chemical mechanism are discussed and proposed. To study oxidant efficiency, chemical oxidants, such as hydrogen peroxide, are also considered. This work is part of a project entitled ''Ultrasonic Process for Detoxification of Groundwater and Soil,'' sponsored by the US Department of Energy, Office of Technology Development, to develop an innovative process for the effective destruction of chlorinated organics in soil and groundwater

  12. Application of ultrasonic inspection data in strength calculations for nuclear power plant equipment

    International Nuclear Information System (INIS)

    Ovchinnikov, A.V.; Rivkin, E.Yu.; Vasilchenko, G.S.; Zvezdin, Yu.I.

    1991-01-01

    Several kinds of test specimens were produced with three types of defects of defined sizes and positions in the particular localities of weld joints. Such specimens have been used for defect parameter characterization by ultrasonic testing. The principles for schematization of such defects and the formulae for the stress intensity factor calculations for elliptical and semielliptical cracks have been worked out. Methods for defining the sizes of defect which are acceptable have been designed for use for use on operational nuclear power plant equipment and take account of the mutual effects of the force, thermal and residual stresses. The method can be used in the brittle, transitional and tough material state. (author)

  13. Modeling and Design of Capacitive Micromachined Ultrasonic Transducers Based-on Database Optimization

    International Nuclear Information System (INIS)

    Chang, M W; Gwo, T J; Deng, T M; Chang, H C

    2006-01-01

    A Capacitive Micromachined Ultrasonic Transducers simulation database, based on electromechanical coupling theory, has been fully developed for versatile capacitive microtransducer design and analysis. Both arithmetic and graphic configurations are used to find optimal parameters based on serial coupling simulations. The key modeling parameters identified can improve microtransducer's character and reliability effectively. This method could be used to reduce design time and fabrication cost, eliminating trial-and-error procedures. Various microtransducers, with optimized characteristics, can be developed economically using the developed database. A simulation to design an ultrasonic microtransducer is completed as an executed example. The dependent relationship between membrane geometry, vibration displacement and output response is demonstrated. The electromechanical coupling effects, mechanical impedance and frequency response are also taken into consideration for optimal microstructures. The microdevice parameters with the best output signal response are predicted, and microfabrication processing constraints and realities are also taken into consideration

  14. FUSION OF VENTURI AND ULTRASONIC FLOW METER FOR ENHANCED FLOW METER CHARACTERISTICS USING FUZZY LOGIC

    Directory of Open Access Journals (Sweden)

    K.V. Santhosh

    2015-04-01

    Full Text Available This paper proposes a technique for measurement of liquid flow using venturi and ultrasonic flow meter(UFM to have following objectives a to design a multi-sensor data fusion (MSDF architecture for using both the sensors, b improve sensitivity and linearity of venturi and ultrasonic flow meter, and c detect and diagnosis of faults in sensor if any. Fuzzy logic algorithm is used to fuse outputs of both the sensor and train the fuzzy block to produces output which has an improved characteristics in terms of both sensitivity and linearity. For identification of sensor faults a comparative test algorithm is designed. Once trained proposed technique is tested in real life, results show successful implementation of proposed objectives.

  15. Output regularization of SVM seizure predictors: Kalman Filter versus the "Firing Power" method.

    Science.gov (United States)

    Teixeira, Cesar; Direito, Bruno; Bandarabadi, Mojtaba; Dourado, António

    2012-01-01

    Two methods for output regularization of support vector machines (SVMs) classifiers were applied for seizure prediction in 10 patients with long-term annotated data. The output of the classifiers were regularized by two methods: one based on the Kalman Filter (KF) and other based on a measure called the "Firing Power" (FP). The FP is a quantification of the rate of the classification in the preictal class in a past time window. In order to enable the application of the KF, the classification problem was subdivided in a two two-class problem, and the real-valued output of SVMs was considered. The results point that the FP method raise less false alarms than the KF approach. However, the KF approach presents an higher sensitivity, but the high number of false alarms turns their applicability negligible in some situations.

  16. Warm-up Practices in Elite Boxing Athletes: Impact on Power Output.

    Science.gov (United States)

    Cunniffe, Brian; Ellison, Mark; Loosemore, Mike; Cardinale, Marco

    2017-01-01

    Cunniffe, B, Ellison, M, Loosemore, M, and Cardinale, M. Warm-up practices in elite boxing athletes: Iimpact on power output. J Strength Cond Res 31(1): 95-105, 2017-This study evaluated the performance impact of routine warm-up strategies in elite Olympic amateur boxing athletes and physiological implications of the time gap (GAP) between warm-up and boxing activity. Six male boxers were assessed while performing standardized prefight warm-up routines. Core and skin temperature measurements (Tcore and Tskin), heart rate, and upper- and lower-body power output (PO) were assessed before and after warm-up, during a 25-minutes GAP and after 3 × 2 minutes rounds of sparring. Reflected temperature (Tc) was also determined using high-resolution thermal images at fixed time-points to explore avenues for heat loss. Despite individual differences in warm-up duration (range 7.4-18.5 minutes), increases in Tcore and Tskin occurred (p ≤ 0.05). Corresponding increases (4.8%; p ≤ 0.05) in countermovement jump (CMJ) height and upward-rightward shifts in upper-body force-velocity and power-velocity curves were observed. Athletes remained inactive during the 25-minutes GAP with a gradual and significant increase in Tc occurring by the end of GAP suggesting the likelihood of heat loss. Decreases in CMJ height and upper-body PO were observed after 15 minutes and 25 minutes GAP (p ≤ 0.05). By the end of GAP period, all performance variables had returned to pre-warm-up values. Results suggest routine warm-ups undertaken by elite boxers have acute effects on power-generating capacity. Gradual decreases in performance variables are evident with inactivity and seem related to alterations in body temperature. Considering the constraints of major competitions and time spent in air conditioned holding areas before fights, practitioners should be aware of the potential of nullifying the warm-up effects.

  17. High Output Piezo/Triboelectric Hybrid Generator

    Science.gov (United States)

    Jung, Woo-Suk; Kang, Min-Gyu; Moon, Hi Gyu; Baek, Seung-Hyub; Yoon, Seok-Jin; Wang, Zhong-Lin; Kim, Sang-Woo; Kang, Chong-Yun

    2015-03-01

    Recently, piezoelectric and triboelectric energy harvesting devices have been developed to convert mechanical energy into electrical energy. Especially, it is well known that triboelectric nanogenerators have a simple structure and a high output voltage. However, whereas nanostructures improve the output of triboelectric generators, its fabrication process is still complicated and unfavorable in term of the large scale and long-time durability of the device. Here, we demonstrate a hybrid generator which does not use nanostructure but generates much higher output power by a small mechanical force and integrates piezoelectric generator into triboelectric generator, derived from the simultaneous use of piezoelectric and triboelectric mechanisms in one press-and-release cycle. This hybrid generator combines high piezoelectric output current and triboelectric output voltage, which produces peak output voltage of ~370 V, current density of ~12 μA.cm-2, and average power density of ~4.44 mW.cm-2. The output power successfully lit up 600 LED bulbs by the application of a 0.2 N mechanical force and it charged a 10 μF capacitor to 10 V in 25 s. Beyond energy harvesting, this work will provide new opportunities for developing a small, built-in power source in self-powered electronics such as mobile electronics.

  18. High Output Piezo/Triboelectric Hybrid Generator

    Science.gov (United States)

    Jung, Woo-Suk; Kang, Min-Gyu; Moon, Hi Gyu; Baek, Seung-Hyub; Yoon, Seok-Jin; Wang, Zhong-Lin; Kim, Sang-Woo; Kang, Chong-Yun

    2015-01-01

    Recently, piezoelectric and triboelectric energy harvesting devices have been developed to convert mechanical energy into electrical energy. Especially, it is well known that triboelectric nanogenerators have a simple structure and a high output voltage. However, whereas nanostructures improve the output of triboelectric generators, its fabrication process is still complicated and unfavorable in term of the large scale and long-time durability of the device. Here, we demonstrate a hybrid generator which does not use nanostructure but generates much higher output power by a small mechanical force and integrates piezoelectric generator into triboelectric generator, derived from the simultaneous use of piezoelectric and triboelectric mechanisms in one press-and-release cycle. This hybrid generator combines high piezoelectric output current and triboelectric output voltage, which produces peak output voltage of ~370 V, current density of ~12 μA·cm−2, and average power density of ~4.44 mW·cm−2. The output power successfully lit up 600 LED bulbs by the application of a 0.2 N mechanical force and it charged a 10 μF capacitor to 10 V in 25 s. Beyond energy harvesting, this work will provide new opportunities for developing a small, built-in power source in self-powered electronics such as mobile electronics. PMID:25791299

  19. Development of an innovative device for ultrasonic elliptical vibration cutting.

    Science.gov (United States)

    Zhou, Ming; Hu, Linhua

    2015-07-01

    An innovative ultrasonic elliptical vibration cutting (UEVC) device with 1st resonant mode of longitudinal vibration and 3rd resonant mode of bending vibration was proposed in this paper, which can deliver higher output power compared to previous UEVC devices. Using finite element method (FEM), resonance frequencies of the longitudinal and bending vibrations were tuned to be as close as possible in order to excite these two vibrations using two-phase driving voltages at a single frequency, while wave nodes of the longitudinal and bending vibrations were also adjusted to be as coincident as possible for mounting the device at a single fixed point. Based on the simulation analysis results a prototype device was fabricated, then its vibration characteristics were evaluated by an impedance analyzer and a laser displacement sensor. With two-phase sinusoidal driving voltages both of 480 V(p-p) at an ultrasonic frequency of 20.1 kHz, the developed prototype device achieved an elliptical vibration with a longitudinal amplitude of 8.9 μm and a bending amplitude of 11.3 μm. The performance of the developed UEVC device is assessed by the cutting tests of hardened steel using single crystal diamond tools. Experimental results indicate that compared to ordinary cutting process, the tool wear is reduced significantly by using the proposed device. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Implementation of a Model Output Statistics based on meteorological variable screening for short‐term wind power forecast

    DEFF Research Database (Denmark)

    Ranaboldo, Matteo; Giebel, Gregor; Codina, Bernat

    2013-01-01

    A combination of physical and statistical treatments to post‐process numerical weather predictions (NWP) outputs is needed for successful short‐term wind power forecasts. One of the most promising and effective approaches for statistical treatment is the Model Output Statistics (MOS) technique....... The proposed MOS performed well in both wind farms, and its forecasts compare positively with an actual operative model in use at Risø DTU and other MOS types, showing minimum BIAS and improving NWP power forecast of around 15% in terms of root mean square error. Further improvements could be obtained...

  1. 1018 nm Yb-doped high-power fiber laser pumped by broadband pump sources around 915 nm with output power above 100 W

    DEFF Research Database (Denmark)

    Midilli, Yakup; Efunbajo, Oyewole Benjamin; Şimşek, Bartu

    2017-01-01

    laser were also addressed in this study. Finally, we have tested this system for high power experimentation and obtained 67% maximum optical-to-optical efficiency at an approximately 110 W output power level. To the best of our knowledge, this is the first 1018 nm ytterbium-doped all-fiber laser pumped...

  2. High-power ultrasonic treatment of contaminated soils and sediments

    International Nuclear Information System (INIS)

    Collings, A.F.; Gwan, P.B.; Sosa Pintos, A.P.

    2004-01-01

    Full text: The propagation of high-power ultrasound through a liquid can initiate the phenomenon of cavitation. This occurs with the collapse of gas bubbles formed during the rarefaction phase of the ultrasonic wave either from the dissolution of air or vaporisation of the liquid. Bubble collapse can generate localised temperatures up to 5,000 K and pressures up to 1,000 atmospheres. Solid particles in slurry have been shown to act as foci for the nucleation and collapse of bubbles. Theory and experiment have confirmed that the rupture of a bubble on a solid surface generates a high speed jet directed towards the surface. In this case, the extreme conditions generated by the non-linear shock wave produced by bubble collapse are localised on the solid surface. Since Persistent Organic Pollutants (POPs) are hydrophobic and are also readily absorbed on the surface of soil particles, the energy released by cavitation in a soil or sediment slurry is selectively directed towards them. The temperatures are sufficient to decompose these molecules. However, the extreme conditions are highly localised and the bulk solution temperature is essentially unaffected. Any decomposition products are immediately quenched and recombination reactions are avoided. Recent advances in ultrasound technology have produced commercial equipment capable of high power which has enabled us to remediate soils and sediments containing Organochlorine Pesticides (OCPs), Polyaromatic Hydrocarbons (PAHs) and Polychlorinated Biphenyls (PCBs). With reductions greater than 80% within minutes, this technique shows great promise with advantages of on-site treatment and reduced operating and capital costs compared with conventional methods

  3. An ultra-low power output capacitor-less low-dropout regulator with slew-rate-enhanced circuit

    Science.gov (United States)

    Cheng, Xin; Zhang, Yu; Xie, Guangjun; Yang, Yizhong; Zhang, Zhang

    2018-03-01

    An ultra-low power output-capacitorless low-dropout (LDO) regulator with a slew-rate-enhanced (SRE) circuit is introduced. The increased slew rate is achieved by sensing the transient output voltage of the LDO and then charging (or discharging) the gate capacitor quickly. In addition, a buffer with ultra-low output impedance is presented to improve line and load regulations. This design is fabricated by SMIC 0.18 μm CMOS technology. Experimental results show that, the proposed LDO regulator only consumes an ultra-low quiescent current of 1.2 μA. The output current range is from 10 μA to 200 mA and the corresponding variation of output voltage is less than 40 mV. Moreover, the measured line regulation and load regulation are 15.38 mV/V and 0.4 mV/mA respectively. Project supported by the National Natural Science Foundation of China (Nos. 61401137, 61404043, 61674049).

  4. Ultrasonic testing

    Energy Technology Data Exchange (ETDEWEB)

    Song, Sung Jin [Sungkwunkwan Univ., Seoul (Korea, Republic of); Jeong, Hyun Jo [Wonkwang Univ., Iksan (Korea, Republic of)

    2004-02-15

    For the proper performance of ultrasonic testing of steel welded joints, and anisotropic material it is necessary to have sound understanding on the underlying physics. To provide such an understanding, it is beneficial to have simulation tools for ultrasonic testing. In order to address such a need, we develop effective approaches to simulate angle beam ultrasonic testing with a personal computer. The simulation is performed using ultrasonic measurement models based on the computationally efficient multi-Gaussian beams. This reach will describe the developed ultrasonic testing models together with the experimental verification of their accuracy.

  5. Ultrasonic sectional imaging for crack identification. Part 1. Confirmation test of essential factors for ultrasonic imaging

    International Nuclear Information System (INIS)

    Sasahara, Toshihiko

    2008-01-01

    Since the first reports of inter-granular stress corrosion crack (IGSCC) in boiling water reactor (BWR) pipe in the 1970s, nuclear power industry has focused considerable attention on service induced crack detection and sizing using ultrasonic examination. In recent years, phased array systems, those reconstruct high quality flaw images at real time are getting to apply for crack detection and sizing. But because the price of phased array systems are expensive for inspection vendors, field application of phased array systems are limited and reliable ultrasonic imaging systems with reasonable price are expected. This paper will discuss cost effective ultrasonic equipment with sectional image (B-scan) presentation as the simplified imaging system for assisting ultrasonic examination personnel. To develop the simplified B-scan imaging system, the frequency characteristics of IGSCC echoes and neighboring geometry echoes such as base-metal to weld interface and inner surface of a pipe are studied. The experimental study confirmed the reflectors have different frequency characteristics and 2MHz is suitable to visualize IGSCC and 5MHz and higher frequency are suitable to reconstruct geometry images. The other study is the amplifier selection for the imaging system. To reconstruct images of IGSCC and geometry echoes, the ultrasonic imaging instrument with linear amplifier has to adjust gain setting to the target. On the other hand, the ultrasonic imaging instrument with logarithmic amplifier can collect and display wider dynamic range on a screen and this wider dynamic range are effective to visualize IGSCC and geometry echoes on a B-scan presentation at a time. (author)

  6. Generalized design of high performance shunt active power filter with output LCL filter

    DEFF Research Database (Denmark)

    Tang, Yi; Loh, Poh Chiang; Wang, Peng

    2012-01-01

    parameters, interactions between resonance damping and harmonic compensation, bandwidth design of the closed-loop system, and active damping implementation with fewer current sensors. These described design concerns, together with their generalized design procedure, are applied to an analytical example......This paper concentrates on the design, control, and implementation of an LCL-filter-based shunt active power filter (SAPF), which can effectively compensate for harmonic currents produced by nonlinear loads in a three-phase three-wire power system. With an LCL filter added at its output...

  7. The Effect of Deflector Angle in Savonius Water Turbine with Horizontal Axis on the Power Output of Water Flow in Pipe

    Science.gov (United States)

    Prasetyo, Ari; Kristiawan, Budi; Danardono, Dominicus; Hadi, Syamsul

    2018-03-01

    Savonius turbine is one type of turbines with simple design and low manufacture. However, this turbine has a relatively low efficiency. This condition can be solved by installing fluid deflectors in the system’s circuit. The deflector is used to direct the focus of the water flow, thus increasing the torque working moment. In this study, a single stage horizontal axis Savonius water turbine was installed on a 3 inch diameter pipeline. This experiment aims to obtain optimal deflector angle design on each water discharge level. The deflector performance is analyzed through power output, TSR, and power coefficient generated by the turbine. The deflector angles tested are without deflector, 20°, 30°, 40°, and 50° with a deflector ratio of 50%. The experimental results at 10.67x10-3m3/s discharge show that turbine equipped with 30° deflector has the most optimal performance of 18.04 Watt power output, TSR of 1.12 and power coefficient 0.127. While with the same discharge, turbine without deflector produces only 9.77 Watt power output, TSR of 0.93, and power coefficient of 0.09. Thus, it can be concluded that the deflector increases power output equal to 85%.

  8. The cavitation erosion of ultrasonic sonotrode during large-scale metallic casting: Experiment and simulation.

    Science.gov (United States)

    Tian, Yang; Liu, Zhilin; Li, Xiaoqian; Zhang, Lihua; Li, Ruiqing; Jiang, Ripeng; Dong, Fang

    2018-05-01

    Ultrasonic sonotrodes play an essential role in transmitting power ultrasound into the large-scale metallic casting. However, cavitation erosion considerably impairs the in-service performance of ultrasonic sonotrodes, leading to marginal microstructural refinement. In this work, the cavitation erosion behaviour of ultrasonic sonotrodes in large-scale castings was explored using the industry-level experiments of Al alloy cylindrical ingots (i.e. 630 mm in diameter and 6000 mm in length). When introducing power ultrasound, severe cavitation erosion was found to reproducibly occur at some specific positions on ultrasonic sonotrodes. However, there is no cavitation erosion present on the ultrasonic sonotrodes that were not driven by electric generator. Vibratory examination showed cavitation erosion depended on the vibration state of ultrasonic sonotrodes. Moreover, a finite element (FE) model was developed to simulate the evolution and distribution of acoustic pressure in 3-D solidification volume. FE simulation results confirmed that significant dynamic interaction between sonotrodes and melts only happened at some specific positions corresponding to severe cavitation erosion. This work will allow for developing more advanced ultrasonic sonotrodes with better cavitation erosion-resistance, in particular for large-scale castings, from the perspectives of ultrasonic physics and mechanical design. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Estimation of international output-energy relation. Effects of alternative output measures

    International Nuclear Information System (INIS)

    Shrestha, R.M.

    2000-01-01

    This paper analyzes the output-energy relationship with alternative measures of output and energy. Our analysis rejects the hypothesis of non-diminishing returns to energy consumption when GDP at purchasing power parities is used as the output measure unlike the case with GNP at market exchange rates. This finding also holds when energy input includes the usage of both commercial and traditional fuels. 13 refs

  10. Design of a 300-Watt Isolated Power Supply with Minimized Circuit Input-to-Output Parasitic Capacitance

    DEFF Research Database (Denmark)

    Nguyen-Duy, Khiem; Petersen, Lars Press; Knott, Arnold

    2014-01-01

    This paper presents the design of a 300-Watt isolated power supply for MOS gate driver circuit in medium and high voltage applications. The key feature of the developed power supply is having a very low circuit input-to-output parasitic capacitance, thus maximizing its noise immunity. This makes...

  11. Intra-Minute Cloud Passing Forecasting Based on a Low Cost IoT Sensor—A Solution for Smoothing the Output Power of PV Power Plants

    Science.gov (United States)

    Sukič, Primož; Štumberger, Gorazd

    2017-01-01

    Clouds moving at a high speed in front of the Sun can cause step changes in the output power of photovoltaic (PV) power plants, which can lead to voltage fluctuations and stability problems in the connected electricity networks. These effects can be reduced effectively by proper short-term cloud passing forecasting and suitable PV power plant output power control. This paper proposes a low-cost Internet of Things (IoT)-based solution for intra-minute cloud passing forecasting. The hardware consists of a Raspberry PI Model B 3 with a WiFi connection and an OmniVision OV5647 sensor with a mounted wide-angle lens, a circular polarizing (CPL) filter and a natural density (ND) filter. The completely new algorithm for cloud passing forecasting uses the green and blue colors in the photo to determine the position of the Sun, to recognize the clouds, and to predict their movement. The image processing is performed in several stages, considering selectively only a small part of the photo relevant to the movement of the clouds in the vicinity of the Sun in the next minute. The proposed algorithm is compact, fast and suitable for implementation on low cost processors with low computation power. The speed of the cloud parts closest to the Sun is used to predict when the clouds will cover the Sun. WiFi communication is used to transmit this data to the PV power plant control system in order to decrease the output power slowly and smoothly. PMID:28505078

  12. The Influence of Serial Carbohydrate Mouth Rinsing on Power Output during a Cycle Sprint.

    Science.gov (United States)

    Phillips, Shaun M; Findlay, Scott; Kavaliauskas, Mykolas; Grant, Marie Clare

    2014-05-01

    The objective of the study was to investigate the influence of serial administration of a carbohydrate (CHO) mouth rinse on performance, metabolic and perceptual responses during a cycle sprint. Twelve physically active males (mean (± SD) age: 23.1 (3.0) years, height: 1.83 (0.07) m, body mass (BM): 86.3 (13.5) kg) completed the following mouth rinse trials in a randomized, counterbalanced, double-blind fashion; 1. 8 x 5 second rinses with a 25 ml CHO (6% w/v maltodextrin) solution, 2. 8 x 5 second rinses with a 25 ml placebo (PLA) solution. Following mouth rinse administration, participants completed a 30 second sprint on a cycle ergometer against a 0.075 g·kg(-1) BM resistance. Eight participants achieved a greater peak power output (PPO) in the CHO trial, resulting in a significantly greater PPO compared with PLA (13.51 ± 2.19 vs. 13.20 ± 2.14 W·kg(-1), p 0.05). No significant between-trials difference was reported for fatigue index, perceived exertion, arousal and nausea levels, or blood lactate and glucose concentrations. Serial administration of a CHO mouth rinse may significantly improve PPO during a cycle sprint. This improvement appears confined to the first 5 seconds of the sprint, and may come at a greater relative cost for the remainder of the sprint. Key pointsThe paper demonstrates that repeated administration of a carbohydrate mouth rinse can significantly improve peak power output during a single 30 second cycle sprint.The ergogenic effect of the carbohydrate mouth rinse may relate to the duration of exposure of the oral cavity to the mouth rinse, and associated greater stimulation of oral carbohydrate receptors.The significant increase in peak power output with the carbohydrate mouth rinse may come at a relative cost for the remainder of the sprint, evidenced by non-significantly lower mean power output and a greater fatigue index in the carbohydrate vs. placebo trial.Serial administration of a carbohydrate mouth rinse may be beneficial for

  13. Wind tunnel study of the power output spectrum in a micro wind farm

    International Nuclear Information System (INIS)

    Bossuyt, Juliaan; Meyers, Johan; Howland, Michael F.; Meneveau, Charles

    2016-01-01

    Instrumented small-scale porous disk models are used to study the spectrum of a surrogate for the power output in a micro wind farm with 100 models of wind turbines. The power spectra of individual porous disk models in the first row of the wind farm show the expected -5/3 power law at higher frequencies. Downstream models measure an increased variance due to wake effects. Conversely, the power spectrum of the sum of the power over the entire wind farm shows a peak at the turbine-to-turbine travel frequency between the model turbines, and a near -5/3 power law region at a much wider range of lower frequencies, confirming previous LES results. Comparison with the spectrum that would result when assuming that the signals are uncorrelated, highlights the strong effects of correlations and anti-correlations in the fluctuations at various frequencies. (paper)

  14. Correlation of COD and BOD of domestic wastewater with the power output of bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Khan, A M; Ataullah,; Shaheen, A; Ahmad, I; Malik, F; Shahid, H A [Federal Urdu University of Arts, Science and Technology, Gulshan-e-Iqbal Campus, University Road, Karachi-75300 (Pakistan). Research Laboratory of Bioenergy, Department of Chemistry

    2011-04-15

    This research article deals with the studies on the development of the correlation of COD, BOD, and BOD/sub 5/ of domestic wastewater (DWW), and fermented domestic wastewater (FDWW) with the power output of the microbial fuel cell (MFC). The fermentation of DWW was carried out with yeast (Saccharomyces cerevisiae), and yogurt bacteria (Streptococcus lactis) to produce biohydrogen which was converted to the electrical energy through the development of microbial fuel cell (MFC). The values of COD, BOD, and BOD/sub 5/ for yogurt fermented domestic wastewater (Yogurt-FDWW) were found to be greater than the values of yeast fermented domestic wastewater (Yeast-FDWW). The power output of DWW and FDWW was increased with the increase in COD, BOD and BOD/sub 5/ values. The main objective of this article is to develop the renewable alternative of fossil fuels which are the major cause of global warming and global pollution. (author)

  15. Correlation of COD and BOD of domestic wastewater with the power output of bioreactor

    International Nuclear Information System (INIS)

    Khan, A.M.; Ataullah; Shaheen, A.; Ahmad, I.; Malik, F.; Shahid, H.A.

    2011-01-01

    This research article deals with the studies on the development of the correlation of COD, BOD, and BOD/sub 5/ of domestic wastewater (DWW), and fermented domestic wastewater (FDWW) with the power output of the microbial fuel cell (MFC). The fermentation of DWW was carried out with yeast (Saccharomyces cerevisiae), and yogurt bacteria (Streptococcus lactis) to produce biohydrogen which was converted to the electrical energy through the development of microbial fuel cell (MFC). The values of COD, BOD, and BOD/sub 5/ for yogurt fermented domestic wastewater (Yogurt-FDWW) were found to be greater than the values of yeast fermented domestic wastewater (Yeast-FDWW). The power output of DWW and FDWW was increased with the increase in COD, BOD and BOD/sub 5/ values. The main objective of this article is to develop the renewable alternative of fossil fuels which are the major cause of global warming and global pollution. (author)

  16. The Role of Visual Feedback on Power Output During Intermittent Wingate Testing in Ice Hockey Players

    Directory of Open Access Journals (Sweden)

    Petr Stastny

    2018-04-01

    Full Text Available Background: Visual feedback may help elicit peak performance during different types of strength and power testing, but its effect during the anaerobic Wingate test is unexplored. Therefore, the purpose of this study was to determine the effect of visual feedback on power output during a hockey-specific intermittent Wingate test (AnWT6x6 consisting of 6 stages of 6 s intervals with a 1:1 work-to-rest ratio. Methods: Thirty elite college-aged hockey players performed the AnWT6x6 with either constant (n = 15 visual feedback during all 6 stages (CVF or restricted (n = 15 visual feedback (RVF where feedback was shown only during the 2nd through 5th stages. Results: In the first stage, there were moderate-to-large effect sizes for absolute peak power (PP output and PP relative to body mass and PP relative to fat-free mass. However, the remaining stages (2–6 displayed small or negligible effects. Conclusions: These data indicate that visual feedback may play a role in optimizing power output in a non-fatigued state (1st stage, but likely does not play a role in the presence of extreme neuromuscular fatigue (6th stage during Wingate testing. To achieve the highest peak power, coaches and researchers could provide visual feedback during Wingate testing, as it may positively influence performance in the early stages of testing, but does not result in residual fatigue or negatively affect performance during subsequent stages.

  17. Output characteristics of Stirling thermoacoustic engine

    International Nuclear Information System (INIS)

    Sun Daming; Qiu Limin; Wang Bo; Xiao Yong; Zhao Liang

    2008-01-01

    A thermoacoustic engine (TE), which converts thermal energy into acoustic power by the thermoacoustic effect, shows several advantages due to the absence of moving parts, such as high reliability and long lifetime associated with reduced manufacturing costs. Power output and efficiency are important criteria of the performance of a TE. In order to increase the acoustic power output and thermal efficiency of a Stirling TE, the acoustic power distribution in the engine is studied with the variable load method. It is found that the thermal efficiency is independent of the output locations along the engine under the same acoustic power output. Furthermore, when the pressure ratio is kept constant at one location along the TE, it is beneficial to increasing the thermal efficiency by exporting more acoustic power. With nitrogen of 2.5 MPa as working gas and the pressure ratio at the compliance of 1.20 in the experiments, the acoustic power is measured at the compliance and the resonator simultaneously. The maximum power output, thermal efficiency and exergy efficiency reach 390.0 W, 11.2% and 16.0%, which are increased by 51.4%, 24.4% and 19.4%, respectively, compared to those with a single R-C load with 750 ml reservoir at the compliance. This research will be instructive for increasing the efficiency and making full use of the acoustic energy of a TE

  18. Milliwatt-level output power in the sub-terahertz range generated by photomixing in a GaAs photoconductor

    Science.gov (United States)

    Peytavit, E.; Lepilliet, S.; Hindle, F.; Coinon, C.; Akalin, T.; Ducournau, G.; Mouret, G.; Lampin, J.-F.

    2011-11-01

    It is shown from accurate on-wafer measurement that continuous wave output powers of 1.2 mW at 50 GHz and 0.35 mW at 305 GHz can be generated by photomixing in a low temperature grown GaAs photoconductor using a metallic mirror Fabry-Pérot cavity. The output power is improved by a factor of about 100 as compared to the previous works on GaAs photomixers. A satisfactory agreement between the theory and the experiment is obtained in considering both the contribution of the holes and the electrons to the total photocurrent.

  19. Conversion of a reactor to partial power output

    International Nuclear Information System (INIS)

    Iljunin, W.G.; Kusnezow, I.A.; Murogow, W.M.; Schmelew, A.N.

    1975-01-01

    The method, among other things, involves an increase in the rate of secondary fissile material production in a fast breeder reactor if the flow of the working fluid through a turbine is reduced as a function of a given amount of reduction of the electric load. This objective will be served by a circuit and circuit variants, respectively, which include a high temperature cooling circuit with, for instance, a sodium cooled HTR, a low temperature cooling circuit with, for instance, a fast or thermal breeder reactor, a working fluid circuit with the turbine, and a heat consumption circuit. In the scheme suggested for operation in the partial power production mode it is envisaged that, as the electric load of the plant decreases the flow of the working fluid upstream of the turbine is kept constant by means of a control system in the working fluid circuit. Additional control systems are used to reduce the amount of heat transmitted by the breeder reactor to the working fluid. The excess amount of heat is distributed to the load connected. This again reduces the temperatures at the inlet and the outlet of the breeder reactor, thus raising its thermal power output. However, the flow through the breeder reactor remains constant all the time. (DG/RF) [de

  20. A model to predict the power output from wind farms

    Energy Technology Data Exchange (ETDEWEB)

    Landberg, L. [Riso National Lab., Roskilde (Denmark)

    1997-12-31

    This paper will describe a model that can predict the power output from wind farms. To give examples of input the model is applied to a wind farm in Texas. The predictions are generated from forecasts from the NGM model of NCEP. These predictions are made valid at individual sites (wind farms) by applying a matrix calculated by the sub-models of WASP (Wind Atlas Application and Analysis Program). The actual wind farm production is calculated using the Riso PARK model. Because of the preliminary nature of the results, they will not be given. However, similar results from Europe will be given.

  1. Power output of microbial fuel cell emphasizing interaction of anodic binder with bacteria

    Science.gov (United States)

    Li, Hongying; Liao, Bo; Xiong, Juan; Zhou, Xingwang; Zhi, Huozhen; Liu, Xiang; Li, Xiaoping; Li, Weishan

    2018-03-01

    Electrochemically active biofilm is necessary for the electron transfer between bacteria and anodic electrode in microbial fuel cells and selecting the type of anodic electrode material that favours formation of electrochemically active biofilm is crucial for the microbial fuel cell operation. We report a new finding that the interaction of anodic binder with bacteria plays more important role than its hydrophilicity for forming an electrochemically active biofilm, which is emphasized by applying poly(bisphenol A-co-epichorohydrin) as an anodic binder of the microbial fuel cell based on carbon nanotubes as anodic electrode and Escherichia coli as bacterium. The physical characterizations and electrochemical measurements demonstrate that poly(bisphenol A-co-epichorohydrin) exhibits a strong interaction with bacteria and thus provides the microbial fuel cell with excellent power density output. The MFC using poly(bisphenol A-co-epichorohydrin) reaches a maximum power density output of 3.8 W m-2. This value is larger than that of the MFCs using polytetrafluoroethylene that has poorer hydrophilicity, or polyvinyl alcohol that has better hydrophilicity but exhibits weaker interaction with bacteria than poly(bisphenol A-co-epichorohydrin).

  2. Preliminary study on rotary ultrasonic machining of Bk-7 optical glass rod

    International Nuclear Information System (INIS)

    Hamzah, E.; Izman, S.; Khoo, C.Y.; Zainal Abidin, N.N.

    2007-01-01

    This paper presents an experimental observation on rotary ultrasonic machining (RUM) of BK7 optical glass rod. BK7 is a common technical optical glass for high quality optical components due to its high linear optical transmission in the visible range and is chemically stable. RUM is a hybrid machining process that combines the material removal mechanisms of diamond grinding and ultrasonic machining (USM) and it is non-thermal, non-chemical, creates no change in the microstructure, chemical or physical properties of the work piece. In the RUM, a controlled static load is applied to the rotating core drill with metal bonded diamond abrasive and is ultrasonically vibrated in the axial direction. A water-soluble coolant was used to cool the tool and sample during machining processes. By using DOE (Design of Experiment) approach, the effect of spindle speed and feed rate to the ultrasonic machinability had been developed. The main effects and two-factor interactions of process parameters (spindle speed) and feed rate) on output variables (MRR, surface roughness, opaqueness, chipping thickness and chipping size) are studied. (author)

  3. Mapping of an ultrasonic bath for ultrasound assisted extraction of mangiferin from Mangifera indica leaves.

    Science.gov (United States)

    Kulkarni, Vrushali M; Rathod, Virendra K

    2014-03-01

    The present work deals with the mapping of an ultrasonic bath for the maximum extraction of mangiferin from Mangifera indica leaves. I3(-) liberation experiments (chemical transformations) and extraction (physical transformations) were carried out at different locations in an ultrasonic bath and compared. The experimental findings indicated a similar trend in variation in an ultrasonic bath by both these methods. Various parameters such as position and depth of vessel in an ultrasonic bath, diameter and shape of a vessel, frequency and input power which affect the extraction yield have been studied in detail. Maximum yield of mangiferin obtained was approximately 31 mg/g at optimized parameters: distance of 2.54 cm above the bottom of the bath, 7 cm diameter of vessel, flat bottom vessel, 6.35 cm liquid height, 122 W input power and 25 kHz frequency. The present work indicates that the position and depth of vessel in an ultrasonic bath, diameter and shape of a vessel, frequency and input power have significant effect on the extraction yield. This work can be used as a base for all ultrasonic baths to obtain maximum efficiency for ultrasound assisted extraction. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Nonlinear NDT: A Route to Conventional Ultrasonic Testing

    OpenAIRE

    Igor Solodov

    2016-01-01

    The bottleneck problem of nonlinear NDT is a low efficiency of conversion from fundamental frequency to nonlinear frequency components. In this paper, it is proposed to use a combination of nonlinearity with Local Defect Resonance (LDR) to enhance substantially the input-output conversion. Since LDR is an efficient resonance “amplifier” of the local vibrations, it manifests a profound nonlinearity even at moderate ultrasonic excitation level. As the driving frequency matches the LDR-frequency...

  5. Fast Reactive Power Sharing, Circulating Current and Resonance Suppression for Parallel Inverters Using Resistive-Capacitive Output Impedance

    DEFF Research Database (Denmark)

    Chen, Yandong; Guerrero, Josep M.; Shuai, Zhikang

    2016-01-01

    In this paper, an inverter using resistivecapacitive output impedance (RC-type inverter) is proposed not only to provide fast reactive power sharing to support microgrid voltage, and but also to reduce circulating currents and damp high-frequency resonances among inverters. Introducing the RC......-frequency resonances among parallel inverters are quantitatively analyzed. The control parameters are systematically selected, and effect of virtual complex impedance on the inverter output voltage is depicted. The RC-type inverter can reduce circulating currents and damp resonances due to different equivalent output...

  6. A dual-mode operation overmoded coaxial millimeter-wave generator with high power capacity and pure transverse electric and magnetic mode output

    Science.gov (United States)

    Bai, Zhen; Zhang, Jun; Zhong, Huihuang

    2016-04-01

    An overmoded coaxial millimeter-wave generator with high power capacity and pure transverse electric and magnetic (TEM) mode output is designed and presented, by using a kind of coaxial slow wave structure (SWS) with large transversal dimension and small distance between inner and outer conductors. The generator works in dual-mode operation mechanism. The electron beam synchronously interacts with 7π/8 mode of quasi-TEM, at the meanwhile exchanges energy with 3π/8 mode of TM01. The existence of TM01 mode, which is traveling wave, not only increases the beam-wave interaction efficiency but also improves the extraction efficiency. The large transversal dimension of coaxial SWS makes its power capacity higher than that of other reported millimeter-wave devices and the small distance between inner and outer conductors allows only two azimuthally symmetric modes to coexist. The converter after the SWS guarantees the mode purity of output power. Particle-in-cell simulation shows that when the diode voltage is 400 kV and beam current is 3.8 kA, the generation of microwave at 32.26 GHz with an output power of 611 MW and a conversion efficiency of 40% is obtained. The power percentage carried by TEM mode reaches 99.7% in the output power.

  7. Universal and inductorless DC/DC converter for multi-output power supplies in sensor and actuator networks

    Science.gov (United States)

    Saponara, Sergio; Ciarpi, Gabriele

    2017-05-01

    This work proposes a universal and inductorless DC/DC converter that can be used for a wide input range, from few V to 60 V, to regulate output voltages from 5 V down to 1 V in Sensor and Actuator Network nodes. The proposed converter has been developed within the Athenis3D European project. It is composed by a cascade of multiple switching capacitor stages, with a proper skip-mode control to implement both step-down and step-up converting ratios, thus regulating all input sources to a voltage of about 6 V. These switching stages are further cascaded with linear regulators, which can provide stable output voltages down to 1 V. The multi-output regulator has been realized as a single-chip in a low-cost 0.35 μm CMOS technology. It is available as a naked die or in a ceramic package. The only needed external components are surface mount capacitors, which can be integrated on top of the naked chip die, creating a 3D structure, using trench capacitors embedded in a passive interposing layer. This way the size of the power management unit is further minimized. An advantage of the proposed converter is that it isn't optimized for a particular input voltage, therefore it can be used with no constant input power, like power harvesting systems (e.g. solar cells, wind and water turbines) and very disturbed power supplies.

  8. Muscle power output properties using the stretch-shortening cycle of the upper limb and their relationships with a one-repetition maximum bench press.

    Science.gov (United States)

    Miyaguchi, Kazuyoshi; Demura, Shinichi

    2006-05-01

    The purpose of this study was to examine the output properties of muscle power by the dominant upper limb using SSC, and the relationships between the power output by SSC and a one-repetition maximum bench press (1 RM BP) used as a strength indicator of the upper body. Sixteen male athletes (21.4+/-0.9 yr) participated in this study. They pulled a load of 40% of maximum voluntary contraction (MVC) at a stretch by elbow flexion of the dominant upper limb in the following three preliminary conditions: static relaxed muscle state (SR condition), isometric muscle contraction state (ISO condition), and using SSC (SSC condition). The velocity with a wire load via a pulley during elbow flexion was measured accurately using a power instrument with a rotary encoder, and the muscle power curve was drawn from the product of the velocity and load. Significant differences were found among all evaluation parameters of muscle power exerted from the above three conditions and the parameters regarding early power output during concentric contraction were larger in the SSC condition than the SR and ISO conditions. The parameters on initial muscle contraction velocity when only using SSC significantly correlated with 1 RM BP (r=0.60-0.62). The use of SSC before powerful elbow flexion may contribute largely to early explosive power output during concentric contraction. Bench press capacity relates to a development of the above early power output when using SSC.

  9. Measurements of output factors with different detector types and Monte Carlo calculations of stopping-power ratios for degraded electron beams

    International Nuclear Information System (INIS)

    Bjoerk, Peter; Knoeoes, Tommy; Nilsson, Per

    2004-01-01

    The aim of the present study was to investigate three different detector types (a parallel-plate ionization chamber, a p-type silicon diode and a diamond detector) with regard to output factor measurements in degraded electron beams, such as those encountered in small-electron-field radiotherapy and intraoperative radiation therapy (IORT). The Monte Carlo method was used to calculate mass collision stopping-power ratios between water and the different detector materials for these complex electron beams (nominal energies of 6, 12 and 20 MeV). The diamond detector was shown to exhibit excellent properties for output factor measurements in degraded beams and was therefore used as a reference. The diode detector was found to be well suited for practical measurements of output factors, although the water-to-silicon stopping-power ratio was shown to vary slightly with treatment set-up and irradiation depth (especially for lower electron energies). Application of ionization-chamber-based dosimetry, according to international dosimetry protocols, will introduce uncertainties smaller than 0.3% into the output factor determination for conventional IORT beams if the variation of the water-to-air stopping-power ratio is not taken into account. The IORT system at our department includes a 0.3 cm thin plastic scatterer inside the therapeutic beam, which furthermore increases the energy degradation of the electrons. By ignoring the change in the water-to-air stopping-power ratio due to this scatterer, the output factor could be underestimated by up to 1.3%. This was verified by the measurements. In small-electron-beam dosimetry, the water-to-air stopping-power ratio variation with field size could mostly be ignored. For fields with flat lateral dose profiles (>3 x 3 cm 2 ), output factors determined with the ionization chamber were found to be in close agreement with the results of the diamond detector. For smaller field sizes the lateral extension of the ionization chamber

  10. Measurements of output factors with different detector types and Monte Carlo calculations of stopping-power ratios for degraded electron beams.

    Science.gov (United States)

    Björk, Peter; Knöös, Tommy; Nilsson, Per

    2004-10-07

    The aim of the present study was to investigate three different detector types (a parallel-plate ionization chamber, a p-type silicon diode and a diamond detector) with regard to output factor measurements in degraded electron beams, such as those encountered in small-electron-field radiotherapy and intraoperative radiation therapy (IORT). The Monte Carlo method was used to calculate mass collision stopping-power ratios between water and the different detector materials for these complex electron beams (nominal energies of 6, 12 and 20 MeV). The diamond detector was shown to exhibit excellent properties for output factor measurements in degraded beams and was therefore used as a reference. The diode detector was found to be well suited for practical measurements of output factors, although the water-to-silicon stopping-power ratio was shown to vary slightly with treatment set-up and irradiation depth (especially for lower electron energies). Application of ionization-chamber-based dosimetry, according to international dosimetry protocols, will introduce uncertainties smaller than 0.3% into the output factor determination for conventional IORT beams if the variation of the water-to-air stopping-power ratio is not taken into account. The IORT system at our department includes a 0.3 cm thin plastic scatterer inside the therapeutic beam, which furthermore increases the energy degradation of the electrons. By ignoring the change in the water-to-air stopping-power ratio due to this scatterer, the output factor could be underestimated by up to 1.3%. This was verified by the measurements. In small-electron-beam dosimetry, the water-to-air stopping-power ratio variation with field size could mostly be ignored. For fields with flat lateral dose profiles (>3 x 3 cm2), output factors determined with the ionization chamber were found to be in close agreement with the results of the diamond detector. For smaller field sizes the lateral extension of the ionization chamber hampers

  11. Brief communication: On the influence of vertical wind shear on the combined power output of two model wind turbines in yaw

    Directory of Open Access Journals (Sweden)

    J. Schottler

    2017-08-01

    Full Text Available The effect of vertical wind shear on the total power output of two aligned model wind turbines as a function of yaw misalignment of the upstream turbine is studied experimentally. It is shown that asymmetries of the power output of the downstream turbine and the combined power of both with respect to the upstream turbine's yaw misalignment angle can be linked to the vertical wind shear of the inflow.

  12. Design, fabrication, and testing of an ultrasonic de-icing system for helicopter rotor blades

    Science.gov (United States)

    Palacios, Jose Luis

    A low-power, non-thermal ultrasonic de-icing system is introduced as a possible substitute for current electro-thermal systems. The system generates delaminating ultrasonic transverse shear stresses at the interface of accreted ice. A PZT-4 disk driven at 28.5 KHz (radial resonance of the disk) instantaneously de-bonds 2 mm thick freezer ice layers. The ice layers are accreted to a 0.7 mm thick, 30.4 cm x 30.4 cm steel plate at an environment temperature of -20°C. A power input of 50 Watts is applied to the actuator (50 V, 19.6 KV/m), which translates to a de-icing power of 0.07 W/cm2. A finite element model of the actuator bonded to the isotropic plate is used to guide the design of the system, and predicts the transverse shear stresses at the ice interface. Wind tunnel icing tests were conducted to demonstrate the potential use of the proposed system under impact icing conditions. Both glaze ice and rime ice were generated on steel and composite plates by changing the cloud conditions of the wind tunnel. Continuous ultrasonic vibration prevented impact ice formation around the actuator location at an input power not exceeding 0.18 W/cm 2 (1.2 W/in2). As ice thickness reached a critical thickness of approximately 1.2 mm, shedding occurred on those locations where ultrasonic transverse shear stresses exceeded the shear adhesion strength of the ice. Finite element transverse shear stress predictions correlate with observed experimental impact ice de-bonding behavior. To increase the traveling distance of propagating ultrasonic waves, ultrasonic shear horizontal wave modes are studied. Wave modes providing large modal interface transverse shear stress concentration coefficients (ISCC) between the host structure (0.7 mm thick steel plate) and accreted ice (2.5 mm thick ice layer) are identified and investigated for a potential increase in the wave propagation distance. Ultrasonic actuators able to trigger these optimum wave modes are designed and fabricated. Despite

  13. Output Pressure and Pulse-Echo Characteristics of CMUTs as Function of Plate Dimensions

    DEFF Research Database (Denmark)

    Diederichsen, Søren Elmin; Hansen, Jesper Mark Fly; Engholm, Mathias

    2017-01-01

    This paper presents an experimental study of the acoustic performance of Capacitive Micromachined Ultrasonic Transducers (CMUTs) as function of plate dimensions. The objective is to increase the output pressure without decreasingthe pulse-echo signal. The CMUTs are fabricated with a LOCOS process......-to-peak output pressure and pulse-echo signal is obtained for the 9.3μm plate, which still has a moderate pulseecho bandwidth of 60%. The 9.3μm plate results in a 1.9 times higher peak-to-peak output pressure and a 3.6 times higherpulse-echo signal compared to the 2μm plate. By adjusting the plate dimensions...

  14. Influence of ultrasonic irradiation on ozone generation in a dielectric barrier discharge

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Drews, J.; Leipold, Frank

    2012-01-01

    An atmospheric pressure dielectric barrier discharge (DBD) was generated in an N2/O2 gas mixture at room temperature with and without ultrasonic irradiation to investigate ozone production. Powerful ultrasonic irradiation with the sound pressure level of approximately 150 dB into the DBD can...

  15. A neural network based computational model to predict the output power of different types of photovoltaic cells.

    Science.gov (United States)

    Xiao, WenBo; Nazario, Gina; Wu, HuaMing; Zhang, HuaMing; Cheng, Feng

    2017-01-01

    In this article, we introduced an artificial neural network (ANN) based computational model to predict the output power of three types of photovoltaic cells, mono-crystalline (mono-), multi-crystalline (multi-), and amorphous (amor-) crystalline. The prediction results are very close to the experimental data, and were also influenced by numbers of hidden neurons. The order of the solar generation power output influenced by the external conditions from smallest to biggest is: multi-, mono-, and amor- crystalline silicon cells. In addition, the dependences of power prediction on the number of hidden neurons were studied. For multi- and amorphous crystalline cell, three or four hidden layer units resulted in the high correlation coefficient and low MSEs. For mono-crystalline cell, the best results were achieved at the hidden layer unit of 8.

  16. A neural network based computational model to predict the output power of different types of photovoltaic cells.

    Directory of Open Access Journals (Sweden)

    WenBo Xiao

    Full Text Available In this article, we introduced an artificial neural network (ANN based computational model to predict the output power of three types of photovoltaic cells, mono-crystalline (mono-, multi-crystalline (multi-, and amorphous (amor- crystalline. The prediction results are very close to the experimental data, and were also influenced by numbers of hidden neurons. The order of the solar generation power output influenced by the external conditions from smallest to biggest is: multi-, mono-, and amor- crystalline silicon cells. In addition, the dependences of power prediction on the number of hidden neurons were studied. For multi- and amorphous crystalline cell, three or four hidden layer units resulted in the high correlation coefficient and low MSEs. For mono-crystalline cell, the best results were achieved at the hidden layer unit of 8.

  17. Process Stability of Ultrasonic-Wave-Assisted Gas Metal Arc Welding

    Science.gov (United States)

    Fan, Chenglei; Xie, Weifeng; Yang, Chunli; Lin, Sanbao; Fan, Yangyang

    2017-10-01

    As a newly developed arc welding method, ultrasonic-wave-assisted arc welding successfully introduced power ultrasound into the arc and weld pool, during which the ultrasonic acts on the top of the arc in the coaxial alignment direction. The advanced process for molten metals can be realized by using an additional ultrasonic field. Compared with the conventional gas metal arc welding (GMAW), the welding arc is compressed, the droplet size is decreased, and the droplet transfer frequency is increased significantly in ultrasonic-wave-assisted GMAW (U-GMAW). However, the stability of the metal transfer has deep influence on the welding quality equally, and the ultrasonic wave effect on the stability of the metal transfer is a phenomenon that is not completely understood. In this article, the stabilities of the short-circuiting transfer process and globular transfer process are studied systematically, and the effect of ultrasonic wave on the metal transfer is analyzed further. The transfer frequency and process stability of the U-GMAW process are much higher than those of the conventional GMAW. Analytical results show that the additional ultrasonic wave is helpful for improving welding stability.

  18. Design of ultrasonic probe and evaluation of ultrasonic waves on E.coli in Sour Cherry Juice

    Directory of Open Access Journals (Sweden)

    B Hosseinzadeh Samani

    2015-09-01

    experimental methodology generates a mathematical model which describes the chemical or biochemical processes (Anjum et al., 1997, Halim et al., 2009. In order to obtain the optimum value, Eq. (1 will be used: (6\tY_i=β_0+∑▒〖β_i X_i+∑▒〖β_ij X_i X_j+〗〗 ∑▒〖β_ij X_i^2 〗+ε where, β0, βj, βij, βjj are regression coefficients for intercept, linear, interaction and quadratic coefficients, respectively, while Xi and Xj are coded independent variables and ε is the error. For this purpose, four factors of ultrasonic power (200 to 600 W, wave exposure time (5 to 15 min, probe diameter (20 to 40 mm, and probe penetration depth in sour cherry juice container (0 to 40 mm were selected. First, the probes with the desired diameters were designed using the related formulas by using CAD-CAM. Results and Discussion: Surface Method (RSM indicated that the quadratic model with 0.96 coefficient of friction, standard error of 1545.3, and coefficient of variation of 14% is the best model for estimating the number of E.coli bacteria among the different studied treatments. The results showed that with increasing probe diameter and probe depth, the destructive effects of ultrasonic wave increase. It was also revealed that as the probe diameter and penetration depth increase, the destructive effect of ultrasonic wave is initially increased and then follows by a decreasing trend. With the increasing power of ultrasonic, ultrasonic intensity increases and leads to reducing number of E.coli in sour cherry juice. The increase in time of treatment with ultrasonic causes a decrease in the number of E.coli in sour cherry juice. This is due to the fact that the increase of ultrasonic exposure time leads to the increase of sonic stream in reactor and results in higher contributions of ultrasonic waves to E.coli. Finally, the examined variables were optimized by RSM and the values of ultrasonic power, waves exposing time, probe diameter, and probe penetration depth were obtained

  19. A Low-Power High-Dynamic-Range Receiver System for In-Probe 3-D Ultrasonic Imaging.

    Science.gov (United States)

    Attarzadeh, Hourieh; Xu, Ye; Ytterdal, Trond

    2017-10-01

    In this paper, a dual-mode low-power, high dynamic-range receiver circuit is designed for the interface with a capacitive micromachined ultrasonic transducer. The proposed ultrasound receiver chip enables the development of an in-probe digital beamforming imaging system. The flexibility of having two operation modes offers a high dynamic range with minimum power sacrifice. A prototype of the chip containing one receive channel, with one variable transimpedance amplifier (TIA) and one analog to digital converter (ADC) circuit is implemented. Combining variable gain TIA functionality with ADC gain settings achieves an enhanced overall high dynamic range, while low power dissipation is maintained. The chip is designed and fabricated in a 65 nm standard CMOS process technology. The test chip occupies an area of 76[Formula: see text] 170 [Formula: see text]. A total average power range of 60-240 [Formula: see text] for a sampling frequency of 30 MHz, and a center frequency of 5 MHz is measured. An instantaneous dynamic range of 50.5 dB with an overall dynamic range of 72 dB is obtained from the receiver circuit.

  20. A methodology based on dynamic artificial neural network for short-term forecasting of the power output of a PV generator

    International Nuclear Information System (INIS)

    Almonacid, F.; Pérez-Higueras, P.J.; Fernández, Eduardo F.; Hontoria, L.

    2014-01-01

    Highlights: • The output of the majority of renewables energies depends on the variability of the weather conditions. • The short-term forecast is going to be essential for effectively integrating solar energy sources. • A new method based on artificial neural network to predict the power output of a PV generator one hour ahead is proposed. • This new method is based on dynamic artificial neural network to predict global solar irradiance and the air temperature. • The methodology developed can be used to estimate the power output of a PV generator with a satisfactory margin of error. - Abstract: One of the problems of some renewables energies is that the output of these kinds of systems is non-dispatchable depending on variability of weather conditions that cannot be predicted and controlled. From this point of view, the short-term forecast is going to be essential for effectively integrating solar energy sources, being a very useful tool for the reliability and stability of the grid ensuring that an adequate supply is present. In this paper a new methodology for forecasting the output of a PV generator one hour ahead based on dynamic artificial neural network is presented. The results of this study show that the proposed methodology could be used to forecast the power output of PV systems one hour ahead with an acceptable degree of accuracy

  1. Real-time prediction models for output power and efficiency of grid-connected solar photovoltaic systems

    International Nuclear Information System (INIS)

    Su, Yan; Chan, Lai-Cheong; Shu, Lianjie; Tsui, Kwok-Leung

    2012-01-01

    Highlights: ► We develop online prediction models for solar photovoltaic system performance. ► The proposed prediction models are simple but with reasonable accuracy. ► The maximum monthly average minutely efficiency varies 10.81–12.63%. ► The average efficiency tends to be slightly higher in winter months. - Abstract: This paper develops new real time prediction models for output power and energy efficiency of solar photovoltaic (PV) systems. These models were validated using measured data of a grid-connected solar PV system in Macau. Both time frames based on yearly average and monthly average are considered. It is shown that the prediction model for the yearly/monthly average of the minutely output power fits the measured data very well with high value of R 2 . The online prediction model for system efficiency is based on the ratio of the predicted output power to the predicted solar irradiance. This ratio model is shown to be able to fit the intermediate phase (9 am to 4 pm) very well but not accurate for the growth and decay phases where the system efficiency is near zero. However, it can still serve as a useful purpose for practitioners as most PV systems work in the most efficient manner over this period. It is shown that the maximum monthly average minutely efficiency varies over a small range of 10.81% to 12.63% in different months with slightly higher efficiency in winter months.

  2. Modeling of Combined Heat and Power Plant Based on a Multi-Stage Gasifier and Internal Combustion Engines of Various Power Outputs

    Science.gov (United States)

    Khudyakova, G. I.; Kozlov, A. N.; Svishchev, D. A.

    2017-11-01

    The paper is concerned with an integrated system of internal combustion engine and mini combined heat and power plant (ICE-CHP). The system is based on multi-stage wood biomass gasification. The use of producer gas in the system affects negatively the internal combustion engine performance and, therefore, reduces the efficiency of the ICE-CHP plant. A mathematical model of an internal combustion engine running on low-calorie producer gas was developed using an overview of Russian and foreign manufacturers of reciprocating units, that was made in the research. A thermal calculation was done for four-stroke gas engines of different rated power outputs (30, 100 and 250 kW), running on producer gas (CO2 - 10.2, CO - 45.8, N2 - 38.8%). Thermal calculation demonstrates that the engine exhaust gas temperature reaches 500 - 600°C at the rated power level and with the lower engine power, the temperature gets higher. For example, for an internal combustion engine power of 1000 kW the temperature of exhaust gases equals 400°C. A comparison of the efficiency of engine operation on natural gas and producer gas shows that with the use of producer gas the power output declines from 300 to 250 kWe. The reduction in the effective efficiency in this case makes up 2%. The measures are proposed to upgrade the internal combustion engine to enable it to run on low-calorie producer gas.

  3. W-band power amplifier MMIC with 400 mW output power in 0.1 μm AlGaN/GaN technology

    NARCIS (Netherlands)

    Heijningen,M. van; Rodenburg, M.; Vliet, F.E. van; Massler, M.; Tessmann, A.; Brückner, F.; Müller, S.; Schwantuschke, D.; Quay; Narhi, T.

    2012-01-01

    The 0.1 μm AlGaN/GaN technology and design of two W-band power amplifiers in this technology are described. The dual-stage amplifier reaches an output power of 400 mW at 90 GHz at an operation bias of 20 V. Two designs with different driver to final stage gate width ratio are discussed. More than 10

  4. Quantifying the Impact of Wind Turbine Wakes on Power Output at Offshore Wind Farms

    DEFF Research Database (Denmark)

    Barthelmie, Rebecca Jane; Pryor, Sara; Frandsen, Sten Tronæs

    2010-01-01

    There is an urgent need to develop and optimize tools for designing large wind farm arrays for deployment offshore. This research is focused on improving the understanding of, and modeling of, wind turbine wakes in order to make more accurate power output predictions for large offshore wind farms...

  5. Effect of ultrasonic pretreatment on purified water disinfection

    International Nuclear Information System (INIS)

    Simon Andreu, P.; Lardin Mifsut, C.; Vergara Romero, L.; Polo Canas, P. M.; Perez Sanchez, P.; Rancano Perez, A.

    2009-01-01

    Due to the importance of a suitable water disinfection in order to insure a pollutant effect minimization against environment, this work has been carried out to determine how can affect an ultrasonic pre-treatment upon disinfection step. It has been confirmed the ultrasonic disintegration of bacterial cells in treated water and disinfectant power of treatment by itself, which is not enough to be used as a single method in water disinfection. It has also been proved that from a technical and economical point of view the combination of UV and ultrasound improves the UV treatment performance. Finally, it has been detected that an ultrasonic pre-treatment increases chlorination effectiveness, however the high cost in this combination makes it unfeasible of industrial scale. (Author) 6 refs

  6. Surface morphology and surface energy of anode materials influence power outputs in a multi-channel mediatorless bio-photovoltaic (BPV) system.

    Science.gov (United States)

    Bombelli, Paolo; Zarrouati, Marie; Thorne, Rebecca J; Schneider, Kenneth; Rowden, Stephen J L; Ali, Akin; Yunus, Kamran; Cameron, Petra J; Fisher, Adrian C; Ian Wilson, D; Howe, Christopher J; McCormick, Alistair J

    2012-09-21

    Bio-photovoltaic cells (BPVs) are a new photo-bio-electrochemical technology for harnessing solar energy using the photosynthetic activity of autotrophic organisms. Currently power outputs from BPVs are generally low and suffer from low efficiencies. However, a better understanding of the electrochemical interactions between the microbes and conductive materials will be likely to lead to increased power yields. In the current study, the fresh-water, filamentous cyanobacterium Pseudanabaena limnetica (also known as Oscillatoria limnetica) was investigated for exoelectrogenic activity. Biofilms of P. limnetica showed a significant photo response during light-dark cycling in BPVs under mediatorless conditions. A multi-channel BPV device was developed to compare quantitatively the performance of photosynthetic biofilms of this species using a variety of different anodic conductive materials: indium tin oxide-coated polyethylene terephthalate (ITO), stainless steel (SS), glass coated with a conductive polymer (PANI), and carbon paper (CP). Although biofilm growth rates were generally comparable on all materials tested, the amplitude of the photo response and achievable maximum power outputs were significantly different. ITO and SS demonstrated the largest photo responses, whereas CP showed the lowest power outputs under both light and dark conditions. Furthermore, differences in the ratios of light : dark power outputs indicated that the electrochemical interactions between photosynthetic microbes and the anode may differ under light and dark conditions depending on the anodic material used. Comparisons between BPV performances and material characteristics revealed that surface roughness and surface energy, particularly the ratio of non-polar to polar interactions (the CQ ratio), may be more important than available surface area in determining biocompatibility and maximum power outputs in microbial electrochemical systems. Notably, CP was readily outperformed by all

  7. Ultrasonic nondestructive evaluation systems industrial application issues

    CERN Document Server

    Callegari, Sergio; Montisci, Augusto; Ricci, Marco; Versaci, Mario

    2015-01-01

    This book covers the practical implementation of ultrasonic NDT techniques in an industrial environment, discussing several issues that may emerge and proposing strategies for addressing them successfully.  It aims to bridge advanced academic research results and their application to industrial procedures. The topics covered in the text range from the basic operation of an ultrasonic NDT system to the simulation of the measurement operations; from the choice and generation of the signals energizing the system to the different ways of exploiting the probes and their output signals; and from quality assessment evaluation to the use of soft computing techniques for classification. Throughout the text, an effort is made to embrace a system view where the physical and technological aspects of sensing are addressed together with higher abstraction levels, such as signal and information processing. Consequently, the book aims at guiding the reader through the various tasks requested for developing a complete ultras...

  8. Pipe Wall Thickness Monitoring Using Dry-Coupled Ultrasonic Waveguide Technique

    International Nuclear Information System (INIS)

    Cheong, Yong Moo; Kim, Ha Nam; Kim, Hong Pyo

    2012-01-01

    In order to monitor a corrosion or FAC (Flow Accelerated Corrosion) in a pipe, there is a need to measure pipe wall thickness at high temperature. Ultrasonic thickness gauging is the most commonly used non-destructive testing technique for wall thickness measurement. However, current commonly available ultrasonic transducers cannot withstand high temperatures, such as above 200 .deg. C. It is therefore necessary to carry out manual measurements during plant shutdowns. The current method thus reveals several disadvantages: inspection have to be performed during shutdowns with the possible consequences of prolonging down time and increasing production losses, insulation has to be removed and replaced for each manual measurement, and scaffolding has to be installed to inaccessible areas, resulting in considerable cost for interventions. It has been suggested that a structural health monitoring approach with permanently installed ultrasonic thickness gauges could have substantial benefits over current practices. The main reasons why conventional piezoelectric ultrasonic transducers cannot be used at high temperatures are that the piezo-ceramic becomes depolarized at temperature above the Curie temperature and because differential thermal expansion of the substrate, couplant, and piezoelectric materials cause failure. In this paper, a shear horizontal waveguide technique for wall thickness monitoring at high temperature is investigated. Two different designs for contact to strip waveguide are shown and the quality of output signal is compared and reviewed. After a success of acquiring high quality ultrasonic signal, experiment on the wall thickness monitoring at high temperature is planned

  9. Establishment and implementation of performance demonstration system for ultrasonic examination in Korea

    International Nuclear Information System (INIS)

    Kim, Yong-sik

    2007-01-01

    Korea Electric Power Research Institute (KEPRI) and Korea Hydro and Nuclear Power Company (KHNP) developed Korean Performance Demonstration (KPD) system for ultrasonic examination applicable to pressurized light-water reactor and pressurized heavy-water reactor power plants in accordance with ASME Sec. XI App. VIII. In order to develop the KPD system following works were completed. 1) Surveying the welds on piping of all nuclear power plants in Korea, 2) Surveying the bolting configuration of all nuclear power plant in Korea, 3) Determining the number and type of test specimens, 4)Designing the test and the practice specimens, 5) Developing quality assurance procedures for the fabrication of test specimens and system management, 6) Developing generic procedures for manual ultrasonic test, 7) Fabrication and fingerprint of test specimen. After establishing the KPD system, round robin tests were conducted to evaluate the accuracy and reliability of examination results by comparing traditional ASME code and performance demonstration method. KEPRI/KHNP had successfully developed the KPD system to fulfill the performance demonstration requirements of ASME Sec. XI, Appendix VIII, and are executing the performance demonstration test for ultrasonic examination system. (author)

  10. A dual-mode operation overmoded coaxial millimeter-wave generator with high power capacity and pure transverse electric and magnetic mode output

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Zhen; Zhang, Jun, E-mail: zhangjun@nudt.edu.cn; Zhong, Huihuang [College of Optoelectric Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

    2016-04-15

    An overmoded coaxial millimeter-wave generator with high power capacity and pure transverse electric and magnetic (TEM) mode output is designed and presented, by using a kind of coaxial slow wave structure (SWS) with large transversal dimension and small distance between inner and outer conductors. The generator works in dual-mode operation mechanism. The electron beam synchronously interacts with 7π/8 mode of quasi-TEM, at the meanwhile exchanges energy with 3π/8 mode of TM{sub 01}. The existence of TM{sub 01} mode, which is traveling wave, not only increases the beam-wave interaction efficiency but also improves the extraction efficiency. The large transversal dimension of coaxial SWS makes its power capacity higher than that of other reported millimeter-wave devices and the small distance between inner and outer conductors allows only two azimuthally symmetric modes to coexist. The converter after the SWS guarantees the mode purity of output power. Particle-in-cell simulation shows that when the diode voltage is 400 kV and beam current is 3.8 kA, the generation of microwave at 32.26 GHz with an output power of 611 MW and a conversion efficiency of 40% is obtained. The power percentage carried by TEM mode reaches 99.7% in the output power.

  11. Response surface methodology for the optimization of sludge solubilization by ultrasonic pre-treatment

    Science.gov (United States)

    Zheng, Mingyue; Zhang, Xiaohui; Lu, Peng; Cao, Qiguang; Yuan, Yuan; Yue, Mingxing; Fu, Yiwei; Wu, Libin

    2018-02-01

    The present study examines the optimization of the ultrasonic pre-treatment conditions with response surface experimental design in terms of sludge disintegration efficiency (solubilisation of organic components). Ultrasonic pre-treatment for the maximum solubilization with residual sludge enhanced the SCOD release. Optimization of the ultrasonic pre-treatment was conducted through a Box-Behnken design (three variables, a total of 17 experiments) to determine the effects of three independent variables (power, residence time and TS) on COD solubilization of sludge. The optimal COD was obtained at 17349.4mg/L, when the power was 534.67W, the time was 10.77, and TS was 2%, while the SE of this condition was 28792J/kg TS.

  12. Ultrasonic signature

    International Nuclear Information System (INIS)

    Borloo, E.; Crutzen, S.

    1974-12-01

    The unique and tamperproof identification technique developed at Ispra is based on ultrasonic Non-Destructive-Techniques. Reading fingerprints with ultrasonic requires high reproducibility of standard apparatus and transducers. The present report gives an exhaustive description of the ultrasonic technique developed for identification purposes. Different applications of the method are described

  13. Saturated Adaptive Output-Feedback Power-Level Control for Modular High Temperature Gas-Cooled Reactors

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2014-11-01

    Full Text Available Small modular reactors (SMRs are those nuclear fission reactors with electrical output powers of less than 300 MWe. Due to its inherent safety features, the modular high temperature gas-cooled reactor (MHTGR has been seen as one of the best candidates for building SMR-based nuclear plants with high safety-level and economical competitive power. Power-level control is crucial in providing grid-appropriation for all types of SMRs. Usually, there exists nonlinearity, parameter uncertainty and control input saturation in the SMR-based plant dynamics. Motivated by this, a novel saturated adaptive output-feedback power-level control of the MHTGR is proposed in this paper. This newly-built control law has the virtues of having relatively neat form, of being strong adaptive to parameter uncertainty and of being able to compensate control input saturation, which are given by constructing Lyapunov functions based upon the shifted-ectropies of neutron kinetics and reactor thermal-hydraulics, giving an online tuning algorithm for the controller parameters and proposing a control input saturation compensator respectively. It is proved theoretically that input-to-state stability (ISS can be guaranteed for the corresponding closed-loop system. In order to verify the theoretical results, this new control strategy is then applied to the large-range power maneuvering control for the MHTGR of the HTR-PM plant. Numerical simulation results show not only the relationship between regulating performance and control input saturation bound but also the feasibility of applying this saturated adaptive control law practically.

  14. Studies on the preparation of Caro’s acid by ultrasonic enhanced electrochemistry

    Science.gov (United States)

    Li, Linbo; Yu, Zeli; Hong, Tao; Fang, Zhao; Peng, Jishi; Yang, Zhao

    2017-06-01

    Ultrasonic cavitation effects can generate hydroxyl radicals and high energy, which is widely applied in the field of oxidation currently. Ultrasound-enhanced electrochemical is used to prepare Caro’s acid, which improves the generate rate of Caro’s acid. In this article, the influences of ultrasonic frequency and ultrasonic power on the electrolysis voltage, electrolyte temperature, electrolyte concentration and the concentration of additive in the process of electrochemical preparation of Caro’s acid was studied. And the optimal production conditions were determined. The research results showed that ultrasonic can significantly improve the production of Caro’s acid and the product can increase by about 20 g/L under the best condition.

  15. Quantum Coherent Three-Terminal Thermoelectrics: Maximum Efficiency at Given Power Output

    Directory of Open Access Journals (Sweden)

    Robert S. Whitney

    2016-05-01

    Full Text Available This work considers the nonlinear scattering theory for three-terminal thermoelectric devices used for power generation or refrigeration. Such systems are quantum phase-coherent versions of a thermocouple, and the theory applies to systems in which interactions can be treated at a mean-field level. It considers an arbitrary three-terminal system in any external magnetic field, including systems with broken time-reversal symmetry, such as chiral thermoelectrics, as well as systems in which the magnetic field plays no role. It is shown that the upper bound on efficiency at given power output is of quantum origin and is stricter than Carnot’s bound. The bound is exactly the same as previously found for two-terminal devices and can be achieved by three-terminal systems with or without broken time-reversal symmetry, i.e., chiral and non-chiral thermoelectrics.

  16. A novel method for predicting the power outputs of wave energy converters

    Science.gov (United States)

    Wang, Yingguang

    2018-03-01

    This paper focuses on realistically predicting the power outputs of wave energy converters operating in shallow water nonlinear waves. A heaving two-body point absorber is utilized as a specific calculation example, and the generated power of the point absorber has been predicted by using a novel method (a nonlinear simulation method) that incorporates a second order random wave model into a nonlinear dynamic filter. It is demonstrated that the second order random wave model in this article can be utilized to generate irregular waves with realistic crest-trough asymmetries, and consequently, more accurate generated power can be predicted by subsequently solving the nonlinear dynamic filter equation with the nonlinearly simulated second order waves as inputs. The research findings demonstrate that the novel nonlinear simulation method in this article can be utilized as a robust tool for ocean engineers in their design, analysis and optimization of wave energy converters.

  17. Analysis of output power and capacity reduction in electrical storage facilities by peak shift control of PV system with bifacial modules

    International Nuclear Information System (INIS)

    Obara, Shin’ya; Konno, Daisuke; Utsugi, Yuta; Morel, Jorge

    2014-01-01

    Highlights: • Characteristics of a large-scale power plant using bifacial solar cell is described. • Conversion efficiency of bifacial photovoltaics obtained using 3D-CAD modeling. • Power supply of bifacial PV can be matched with demand by adjusting the orientation. - Abstract: Bifacial photovoltaics are widely investigated with the aim of reducing the amount of silicon used and increasing conversion efficiencies. The output power of bifacial photovoltaics depends on the quantity of solar radiation incident on the reverse face. Furthermore, controlling the orientation can distribute the times of peak power output in the morning and afternoon to better match the demand. In this study, the demand patterns of individual houses or the whole Hokkaido region were analyzed assuming the substitution of a conventional large-scale electric power system with one using bifacial photovoltaics. The supply–demand balances and electrical storage capacities were investigated. When comparing a large scale solar power plant (mega-solar power plant) using monofacial photovoltaics or vertical bifacial photovoltaics (in which the orientation could be adjusted), the supply–demand could be better balanced for individual houses in the latter case, thereby allowing the storage capacity to be reduced. A bifacial solar module was modeled by 3D-CAD (three dimensional computer aided design) and thermal fluid analysis. The module temperature distribution of bifacial photovoltaics was calculated with respect to the environmental conditions (wind flow, direct and diffuse solar radiation, etc.) and internal heat generation, as well as the orientation of the solar panels. Furthermore, the output power of bifacial photovoltaics can be easily obtained from the analysis result of modular temperature distribution and the relation between temperature and output power

  18. Gain compression and its dependence on output power in quantum dot lasers

    Science.gov (United States)

    Zhukov, A. E.; Maximov, M. V.; Savelyev, A. V.; Shernyakov, Yu. M.; Zubov, F. I.; Korenev, V. V.; Martinez, A.; Ramdane, A.; Provost, J.-G.; Livshits, D. A.

    2013-06-01

    The gain compression coefficient was evaluated by applying the frequency modulation/amplitude modulation technique in a distributed feedback InAs/InGaAs quantum dot laser. A strong dependence of the gain compression coefficient on the output power was found. Our analysis of the gain compression within the frame of the modified well-barrier hole burning model reveals that the gain compression coefficient decreases beyond the lasing threshold, which is in a good agreement with the experimental observations.

  19. Trends of the electricity output, power conversion efficiency, and the grid emission factor in North Korea

    Science.gov (United States)

    Yeo, M. J.; Kim, Y. P.

    2017-12-01

    Recently, concerns about the atmospheric environmental problems in North Korea (NK) have been growing. According to the World Health Organization (WHO) (2017), NK was the first ranked country in mortality rate attributed to household and ambient air pollution in 2012. Reliable energy-related data in NK were needed to understand the characteristics of air quality in NK. However, data from the North Korean government were limited. Nevertheless, we could find specific energy-related data produced by NK in the Project Design Documents (PDDs) of the Clean Development Mechanism (CDM) submitted to the United Nations Framework Convention on Climate Change (UNFCCC). There were the 6 registered CDM projects hosted by North Korea, developed as small hydropower plants. Several data of each power plant, such as the electricity output, connected to the Eastern Power Grid (EPG) or the Western Power Grid (WPG) in North Korea were provided in the CDM PDDs. We (1) figured out the trends of the electricity output, the `power conversion efficiency' which we defined the amount of generated electricity to the supplied input primary energy for power generation, and fuel mix as grid emission factor in NK as using the data produced by NK between 2005 and 2009, (2) discussed the operating status of the thermal power plants in NK, and (3) discussed the energy/environmental-related policies and the priority issues in NK in this study.

  20. Ultrasonic pretreatment for enhanced saccharification and fermentation of ethanol production from corn

    Science.gov (United States)

    Montalbo-Lomboy, Melissa T.

    The 21st Century human lifestyle has become heavily dependent on hydrocarbon inputs. Energy demand and the global warming effects due to the burning of fossil fuels have continued to increase. Rising awareness of the negative environmental and economic impacts of hydrocarbon dependence has led to a resurgence of interest in renewable energy sources such as ethanol. Fuel ethanol is known to be a cleaner and renewable source of energy relative to gasoline. Many studies have agreed that fuel ethanol has reduced greenhouse gas (GHG) emissions and has larger overall energy benefits compared to gasoline. Currently, the majority of the fuel ethanol in the United States is produced from corn using dry-grind milling process. The typical dry-grind ethanol plant incorporates jet cooking using steam to cook the corn slurry as pretreatment for saccharification; an energy intensive step. In aiming to reduce energy usage, this study evaluated the use of ultrasonics as an alternative to jet cooking. Ultrasonic batch experiments were conducted using a Branson 2000 Series bench-scale ultrasonic unit operating at a frequency of 20 kHz and a maximum output of 2.2 kW. Corn slurry was sonicated at varying amplitudes from 192 to 320 mumpeak-to-peak(p-p) for 0-40 seconds. Enzyme stability was investigated by adding enzyme (STARGEN(TM)001) before and after sonication. Scanning electron micrograph (SEM) images and particle size distribution analysis showed a nearly 20-fold size reduction by disintegration of corn particles due to ultrasonication. The results also showed a 30% improvement in sugar release of sonicated samples relative to the control group (untreated). The efficiency exceeded 100% in terms of relative energy gain from the additional sugar released due to ultrasonication compared to the ultrasonic energy applied. Interestingly, enzymatic activity was enhanced when sonicated at low and medium power. This result suggested that ultrasonic energy did not denature the enzymes

  1. Measuring cutaneous thermal nociception in group-housed pigs using laser technique - effects of laser power output

    DEFF Research Database (Denmark)

    Herskin, Mette S.; Ladevig, Jan; Arendt-Nielsen, Lars

    2009-01-01

    Nociceptive testing is a valuable tool in the development of pharmaceutical products, for basic nociceptive research, and for studying changes in pain sensitivity is investigated after inflammatory states or nerve injury. However, in pigs only very limited knowledge about nociceptive processes...... nociceptive stimulation from a computer-controlled CO2-laser beam applied to either the caudal part of the metatarsus on the hind legs or the shoulder region of gilts. In Exp. 1, effects of laser power output (0, 0.5, 1, 1.5 and 2 W) on nociceptive responses toward stimulation on the caudal aspects...... of the metatarsus were examined using 15 gilts kept in one group and tested in individual feeding stalls after feeding. Increasing the power output led to gradually decreasing latency to respond (P 

  2. Non-contact feature detection using ultrasonic Lamb waves

    Science.gov (United States)

    Sinha, Dipen N [Los Alamos, NM

    2011-06-28

    Apparatus and method for non-contact ultrasonic detection of features on or within the walls of hollow pipes are described. An air-coupled, high-power ultrasonic transducer for generating guided waves in the pipe wall, and a high-sensitivity, air-coupled transducer for detecting these waves, are disposed at a distance apart and at chosen angle with respect to the surface of the pipe, either inside of or outside of the pipe. Measurements may be made in reflection or transmission modes depending on the relative position of the transducers and the pipe. Data are taken by sweeping the frequency of the incident ultrasonic waves, using a tracking narrow-band filter to reduce detected noise, and transforming the frequency domain data into the time domain using fast Fourier transformation, if required.

  3. Further Investigations on Simultaneous Ultrasonic Coal Flotation

    Directory of Open Access Journals (Sweden)

    Safak Gokhan Ozkan

    2017-09-01

    Full Text Available This study investigates the flotation performance of a representative hard coal slime sample (d80 particle size of minus 0.2 mm obtained from the Prosper-Haniel coal preparation plant located in Bottrop, Germany. Flotation was carried out with a newly designed flotation cell refurbished from an old ultrasonic cleaning bath (2.5 L volume equipped with a single frequency (35 kHz and two different power levels (80–160 W and a sub-aeration-type flotation machine operating at a stable impeller speed (1200 rpm and air rate (2.5 L/min. The reagent combination for conventional and simultaneous ultrasonic coal flotation tests was Ekofol-440 at variable dosages (40–300 g/t with controlling water temperature (20–25 °C at natural pH (6.5–7.0. The batch coal flotation results were analyzed by comparing the combustible recovery (% and separation efficiency (% values, taking mass yield and ash concentrations of the froths and tailings into account. It was found that simultaneous ultrasonic coal flotation increased yield and recovery values of the floated products with lower ash values than the conventional flotation despite using similar reagent dosages. Furthermore, particle size distribution of the ultrasonically treated and untreated coals was measured. Finely distributed coal particles seemed to be agglomerated during the ultrasonic treatment, while ash-forming slimes were removed by hydrodynamic cavitation.

  4. Influence of the level of fit of a density probability function to wind-speed data on the WECS mean power output estimation

    International Nuclear Information System (INIS)

    Carta, Jose A.; Ramirez, Penelope; Velazquez, Sergio

    2008-01-01

    Static methods which are based on statistical techniques to estimate the mean power output of a WECS (wind energy conversion system) have been widely employed in the scientific literature related to wind energy. In the static method which we use in this paper, for a given wind regime probability distribution function and a known WECS power curve, the mean power output of a WECS is obtained by resolving the integral, usually using numerical evaluation techniques, of the product of these two functions. In this paper an analysis is made of the influence of the level of fit between an empirical probability density function of a sample of wind speeds and the probability density function of the adjusted theoretical model on the relative error ε made in the estimation of the mean annual power output of a WECS. The mean power output calculated through the use of a quasi-dynamic or chronological method, that is to say using time-series of wind speed data and the power versus wind speed characteristic of the wind turbine, serves as the reference. The suitability of the distributions is judged from the adjusted R 2 statistic (R a 2 ). Hourly mean wind speeds recorded at 16 weather stations located in the Canarian Archipelago, an extensive catalogue of wind-speed probability models and two wind turbines of 330 and 800 kW rated power are used in this paper. Among the general conclusions obtained, the following can be pointed out: (a) that the R a 2 statistic might be useful as an initial gross indicator of the relative error made in the mean annual power output estimation of a WECS when a probabilistic method is employed; (b) the relative errors tend to decrease, in accordance with a trend line defined by a second-order polynomial, as R a 2 increases

  5. Piston cylinder cell for high pressure ultrasonic pulse echo measurements

    Energy Technology Data Exchange (ETDEWEB)

    Kepa, M. W., E-mail: mkepa@staffmail.ed.ac.uk; Huxley, A. D. [SUPA, Centre for Science at Extreme Conditions and School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3JZ (United Kingdom); Ridley, C. J.; Kamenev, K. V. [Centre for Science at Extreme Conditions and School of Engineering, University of Edinburgh, Edinburgh EH9 3FD (United Kingdom)

    2016-08-15

    Ultrasonic techniques such as pulse echo, vibrating reed, or resonant ultrasound spectroscopy are powerful probes not only for studying elasticity but also for investigating electronic and magnetic properties. Here, we report on the design of a high pressure ultrasonic pulse echo apparatus, based on a piston cylinder cell, with a simplified electronic setup that operates with a single coaxial cable and requires sample lengths of mm only. The design allows simultaneous measurements of ultrasonic velocities and attenuation coefficients up to a pressure of 1.5 GPa. We illustrate the performance of the cell by probing the phase diagram of a single crystal of the ferromagnetic superconductor UGe{sub 2}.

  6. Ultrasonic and radiographic evaluation of advanced aerospace materials: Ceramic composites

    Science.gov (United States)

    Generazio, Edward R.

    1990-01-01

    Two conventional nondestructive evaluation techniques were used to evaluate advanced ceramic composite materials. It was shown that neither ultrasonic C-scan nor radiographic imaging can individually provide sufficient data for an accurate nondestructive evaluation. Both ultrasonic C-scan and conventional radiographic imaging are required for preliminary evaluation of these complex systems. The material variations that were identified by these two techniques are porosity, delaminations, bond quality between laminae, fiber alignment, fiber registration, fiber parallelism, and processing density flaws. The degree of bonding between fiber and matrix cannot be determined by either of these methods. An alternative ultrasonic technique, angular power spectrum scanning (APSS) is recommended for quantification of this interfacial bond.

  7. Ultrasonic horn design for ultrasonic machining technologies

    Directory of Open Access Journals (Sweden)

    Naď M.

    2010-07-01

    Full Text Available Many of industrial applications and production technologies are based on the application of ultrasound. In many cases, the phenomenon of ultrasound is also applied in technological processes of the machining of materials. The main element of equipments that use the effects of ultrasound for machining technology is the ultrasonic horn – so called sonotrode. The performance of ultrasonic equipment, respectively ultrasonic machining technologies depends on properly designed of sonotrode shape. The dynamical properties of different geometrical shapes of ultrasonic horns are presented in this paper. Dependence of fundamental modal properties (natural frequencies, mode shapes of various sonotrode shapes for various geometrical parameters is analyzed. Modal analyses of the models are determined by the numerical simulation using finite element method (FEM design procedures. The mutual comparisons of the comparable parameters of the various sonotrode shapes are presented.

  8. Maximizing Power Output in Homogeneous Charge Compression Ignition (HCCI) Engines and Enabling Effective Control of Combustion Timing

    Science.gov (United States)

    Saxena, Samveg

    Homogeneous Charge Compression Ignition (HCCI) engines are one of the most promising engine technologies for the future of energy conversion from clean, efficient combustion. HCCI engines allow high efficiency and lower CO2 emission through the use of high compression ratios and the removal of intake throttle valves (like Diesel), and allow very low levels of urban pollutants like nitric oxide and soot (like Otto). These engines, however, are not without their challenges, such as low power density compared with other engine technologies, and a difficulty in controlling combustion timing. This dissertation first addresses the power output limits. The particular strategies for enabling high power output investigated in this dissertation focus on avoiding five critical limits that either damage an engine, drastically reduce efficiency, or drastically increase emissions: (1) ringing limits, (2) peak in-cylinder pressure limits, (3) misfire limits, (4) low intake temperature limits, and (5) excessive emissions limits. The research shows that the key factors that enable high power output, sufficient for passenger vehicles, while simultaneously avoiding the five limits defined above are the use of: (1) high intake air pressures allowing improved power output, (2) highly delayed combustion timing to avoid ringing limits, and (3) using the highest possible equivalence ratio before encountering ringing limits. These results are revealed by conducting extensive experiments spanning a wide range of operating conditions on a multi-cylinder HCCI engine. Second, this dissertation discusses strategies for effectively sensing combustion characteristics on a HCCI engine. For effective feedback control of HCCI combustion timing, a sensor is required to quantify when combustion occurs. Many laboratory engines use in-cylinder pressure sensors but these sensors are currently prohibitively expensive for wide-scale commercialization. Instead, ion sensors made from inexpensive sparkplugs

  9. Review of piezoelectric micromachined ultrasonic transducers and their applications

    International Nuclear Information System (INIS)

    Jung, Joontaek; Lee, Wonjun; Kang, Woojin; Shin, Eunjung; Choi, Hongsoo; Ryu, Jungho

    2017-01-01

    In recent decades, micromachined ultrasonic transducers (MUTs) have been investigated as an alternative to conventional piezocomposite ultrasonic transducers, primarily due to the advantages that microelectromechanical systems provide. Miniaturized ultrasonic systems require ultrasonic transducers integrated with complementary metal-oxide-semiconductor circuits. Hence, piezoelectric MUTs (pMUTs) and capacitive MUTs (cMUTs) have been developed as the most favorable solutions. This paper reviews the basic equations to understand the characteristics of thin-film-based piezoelectric devices and presents recent research on pMUTs, including current approaches and limitations. Methods to improve the coupling coefficient of pMUTs are also investigated, such as device structure, materials, and fabrication techniques. The device structure improvements include multielectrode pMUTs, partially clamped boundary conditions, and 3D pMUTs (curved and domed types), where the latter can provide an electromechanical coupling coefficient of up to 45%. The piezoelectric coefficient ( e 31 ) can be increased by controlling the crystal texture (seed layer of γ -Al 2 O 3 ), using single-crystal (PMN-PT) materials, or control of residual stresses (using SiO 2 layer). Arrays of pMUTs can be implemented for various applications including intravascular ultrasound, fingerprint sensors, rangefinders in air, and wireless power supply systems. pMUTs are expected to be an ideal solution for applications such as mobile biometric security (fingerprint sensors) and rangefinders due to their superior power efficiency and compact size. (topical review)

  10. Review of piezoelectric micromachined ultrasonic transducers and their applications

    Science.gov (United States)

    Jung, Joontaek; Lee, Wonjun; Kang, Woojin; Shin, Eunjung; Ryu, Jungho; Choi, Hongsoo

    2017-11-01

    In recent decades, micromachined ultrasonic transducers (MUTs) have been investigated as an alternative to conventional piezocomposite ultrasonic transducers, primarily due to the advantages that microelectromechanical systems provide. Miniaturized ultrasonic systems require ultrasonic transducers integrated with complementary metal-oxide-semiconductor circuits. Hence, piezoelectric MUTs (pMUTs) and capacitive MUTs (cMUTs) have been developed as the most favorable solutions. This paper reviews the basic equations to understand the characteristics of thin-film-based piezoelectric devices and presents recent research on pMUTs, including current approaches and limitations. Methods to improve the coupling coefficient of pMUTs are also investigated, such as device structure, materials, and fabrication techniques. The device structure improvements include multielectrode pMUTs, partially clamped boundary conditions, and 3D pMUTs (curved and domed types), where the latter can provide an electromechanical coupling coefficient of up to 45%. The piezoelectric coefficient (e 31) can be increased by controlling the crystal texture (seed layer of γ-Al2O3), using single-crystal (PMN-PT) materials, or control of residual stresses (using SiO2 layer). Arrays of pMUTs can be implemented for various applications including intravascular ultrasound, fingerprint sensors, rangefinders in air, and wireless power supply systems. pMUTs are expected to be an ideal solution for applications such as mobile biometric security (fingerprint sensors) and rangefinders due to their superior power efficiency and compact size.

  11. An implementation of signal processing algorithms for ultrasonic NDE

    International Nuclear Information System (INIS)

    Ericsson, L.; Stepinski, T.

    1994-01-01

    Probability of detection flaws during ultrasonic pulse-echo inspection is often limited by the presence of backscattered echoes from the material structure. A digital signal processing technique for removal of this material noise, referred to as split spectrum processing (SSP), has been developed and verified using laboratory experiments during the last decade. The authors have performed recently a limited scale evaluation of various SSP techniques for ultrasonic signals acquired during the inspection of welds in austenitic steel. They have obtained very encouraging results that indicate promising capabilities of the SSP for inspection of nuclear power plants. Thus, a more extensive investigation of the technique using large amounts of ultrasonic data is motivated. This analysis should employ different combinations of materials, flaws and transducers. Due to the considerable number of ultrasonic signals required to verify the technique for future practical use, a custom-made computer software is necessary. At the request of the Swedish nuclear power industry the authors have developed such a program package. The program provides a user-friendly graphical interface and is intended for processing of B-scan data in a flexible way. Assembled in the program are a number of signal processing algorithms including traditional Split Spectrum Processing and the more recent Cut Spectrum Processing algorithm developed by them. The program and some results obtained using the various algorithms are presented in the paper

  12. A new approach involving a multi transducer ultrasonic system for cleaning turbine engines' oil filters under practical conditions.

    Science.gov (United States)

    Nguyen, Dinh Duc; Ngo, Huu Hao; Yoon, Yong Soo; Chang, Soon Woong; Bui, Hong Ha

    2016-09-01

    The purpose of this paper is to provide a green technology that can clean turbine engine oil filters effectively in ships using ultrasound, with ultrasonic devices having a frequency of 25kHz and different powers of 300W and 600W, respectively. The effects of temperature, ultrasonic cleaning times, pressure losses through the oil filter, solvent washing, and ultrasonic power devices were investigated. In addition, the cleaning efficiency of three modes (hand washing, preliminary washing and ultrasonic washing) were compared to assess their relative effectiveness. Experimental results revealed that the necessary ultrasonic time varied significantly depending on which solvent was used for washing. For instance, the optimum ultrasonic cleaning time was 50-60min when the oil filter was cleaned in a solvent of kerosene oil (KO) and over 80min when in a solvent of diesel oil (DO) using the same ultrasonic generator device (25kHz, 600W) and experimental conditions. Furthermore, microscopic examination did not reveal any damage or breakdown on or within the structure of the filter after ultrasonic cleaning, even in the filter's surfaces at a constantly low frequency of 25kHz and power specific capacity (100W/gal). Overall, it may be concluded that ultrasound-assisted oil filter washing is effective, requiring a significantly shorter time than manual washing. This ultrasonic method also shows promise as a green technology for washing oil filters in turbine engines in general and Vietnamese navy ships in particular, because of its high cleaning efficiency, operational simplicity and savings. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Parameter analysis on the ultrasonic TSV-filling process and electrochemical characters

    Science.gov (United States)

    Wang, Fuliang; Ren, Xinyu; Wang, Yan; Zeng, Peng; Zhou, Zhaohua; Xiao, Hongbin; Zhu, Wenhui

    2017-10-01

    As one of the key technologies in 3D packaging, through silicon via (TSV) interconnection technology has become a focus recently. In this paper, an electrodeposition method for TSV filling with the assistance of ultrasound and additives are introduced. Two important parameters i.e. current density and ultrasonic power are studied for TSV filling process and electrochemical properties. It is found that ultrasound can improve the quality of TSV-filling and change the TSV-filling mode. The experimental results also indicate that the filling rate enhances more significantly with decreasing current density under ultrasonic conditions than under silent conditions. In addition, according to the voltammetry curve, the increase of ultrasonic power can significantly increase the current density of cupric reduction, and decrease the thickness of diffusion layer. So that the reduction speed of copper ions is accelerated, resulting in a higher TSV-filling rate.

  14. Bulk ultrasonic NDE of metallic components at high temperature using magnetostrictive transducers

    Science.gov (United States)

    Ashish, Antony Jacob; Rajagopal, Prabhu; Balasubramaniam, Krishnan; Kumar, Anish; Rao, B. Purnachandra; Jayakumar, Tammana

    2017-02-01

    Online ultrasonic NDE at high-temperature is of much interest to the power, process and automotive industries in view of possible savings in downtime. This paper describes a novel approach to developing ultrasonic transducers capable of high-temperature in-situ operation using the principle of magnetostriction. Preliminary design from previous research by the authors [1] is extended for operation at 1 MHz, and at elevated temperatures by amorphous metallic strips as the magnetostrictive core. Ultrasonic signals in pulse-echo mode are experimentally obtained from the ultrasonic transducer thus developed, in a simulated high-temperature environment of 350 °C for 10 hours. Advantages and challenges for practical deployment of this approach are discussed.

  15. Effect of ultrasonic, sonic and rotating-oscillating powered toothbrushing systems on surface roughness and wear of white spot lesions and sound enamel: An in vitro study.

    Science.gov (United States)

    Hernandé-Gatón, Patrícia; Palma-Dibb, Regina Guenka; Silva, Léa Assed Bezerra da; Faraoni, Juliana Jendiroba; de Queiroz, Alexandra Mussolino; Lucisano, Marília Pacífico; Silva, Raquel Assed Bezerra da; Nelson Filho, Paulo

    2018-04-01

    To evaluate the effect of ultrasonic, sonic and rotating-oscillating powered toothbrushing systems on surface roughness and wear of white spot lesions and sound enamel. 40 tooth segments obtained from third molar crowns had the enamel surface divided into thirds, one of which was not subjected to toothbrushing. In the other two thirds, sound enamel and enamel with artificially induced white spot lesions were randomly assigned to four groups (n=10) : UT: ultrasonic toothbrush (Emmi-dental); ST1: sonic toothbrush (Colgate ProClinical Omron); ST2: sonic toothbrush (Sonicare Philips); and ROT: rotating-oscillating toothbrush (control) (Oral-B Professional Care Triumph 5000 with SmartGuide). The specimens were analyzed by confocal laser microscopy for surface roughness and wear. Data were analyzed statistically by paired t-tests, Kruskal-Wallis, two-way ANOVA and Tukey's post-test (α= 0.05). The different powered toothbrushing systems did not cause a significant increase in the surface roughness of sound enamel (P> 0.05). In the ROT group, the roughness of white spot lesion surface increased significantly after toothbrushing and differed from the UT group (Pspot lesion compared with sound enamel, and this group differed significantly from the ST1 group (Pspot lesion increased surface roughness and wear. None of the powered toothbrushing systems (ultrasonic, sonic and rotating-oscillating) tested caused significant alterations on sound dental enamel. However, conventional rotating-oscillating toothbrushing on enamel with white spot lesion increased surface roughness and wear. Copyright©American Journal of Dentistry.

  16. A capacitive ultrasonic transducer based on parametric resonance

    Science.gov (United States)

    Surappa, Sushruta; Satir, Sarp; Levent Degertekin, F.

    2017-07-01

    A capacitive ultrasonic transducer based on a parametric resonator structure is described and experimentally demonstrated. The transducer structure, which we call capacitive parametric ultrasonic transducer (CPUT), uses a parallel plate capacitor with a movable membrane as part of a degenerate parametric series RLC resonator circuit with a resonance frequency of fo. When the capacitor plate is driven with an incident harmonic ultrasonic wave at the pump frequency of 2fo with sufficient amplitude, the RLC circuit becomes unstable and ultrasonic energy can be efficiently converted to an electrical signal at fo frequency in the RLC circuit. An important characteristic of the CPUT is that unlike other electrostatic transducers, it does not require DC bias or permanent charging to be used as a receiver. We describe the operation of the CPUT using an analytical model and numerical simulations, which shows drive amplitude dependent operation regimes including parametric resonance when a certain threshold is exceeded. We verify these predictions by experiments with a micromachined membrane based capacitor structure in immersion where ultrasonic waves incident at 4.28 MHz parametrically drive a signal with significant amplitude in the 2.14 MHz RLC circuit. With its unique features, the CPUT can be particularly advantageous for applications such as wireless power transfer for biomedical implants and acoustic sensing.

  17. Ultrasonic imaging of material flaws exploiting multipath information

    Science.gov (United States)

    Shen, Xizhong; Zhang, Yimin D.; Demirli, Ramazan; Amin, Moeness G.

    2011-05-01

    In this paper, we consider ultrasonic imaging for the visualization of flaws in a material. Ultrasonic imaging is a powerful nondestructive testing (NDT) tool which assesses material conditions via the detection, localization, and classification of flaws inside a structure. Multipath exploitations provide extended virtual array apertures and, in turn, enhance imaging capability beyond the limitation of traditional multisensor approaches. We utilize reflections of ultrasonic signals which occur when encountering different media and interior discontinuities. The waveforms observed at the physical as well as virtual sensors yield additional measurements corresponding to different aspect angles. Exploitation of multipath information addresses unique issues observed in ultrasonic imaging. (1) Utilization of physical and virtual sensors significantly extends the array aperture for image enhancement. (2) Multipath signals extend the angle of view of the narrow beamwidth of the ultrasound transducers, allowing improved visibility and array design flexibility. (3) Ultrasonic signals experience difficulty in penetrating a flaw, thus the aspect angle of the observation is limited unless access to other sides is available. The significant extension of the aperture makes it possible to yield flaw observation from multiple aspect angles. We show that data fusion of physical and virtual sensor data significantly improves the detection and localization performance. The effectiveness of the proposed multipath exploitation approach is demonstrated through experimental studies.

  18. Prediction of ultrasonic pulse velocity for enhanced peat bricks using adaptive neuro-fuzzy methodology.

    Science.gov (United States)

    Motamedi, Shervin; Roy, Chandrabhushan; Shamshirband, Shahaboddin; Hashim, Roslan; Petković, Dalibor; Song, Ki-Il

    2015-08-01

    Ultrasonic pulse velocity is affected by defects in material structure. This study applied soft computing techniques to predict the ultrasonic pulse velocity for various peats and cement content mixtures for several curing periods. First, this investigation constructed a process to simulate the ultrasonic pulse velocity with adaptive neuro-fuzzy inference system. Then, an ANFIS network with neurons was developed. The input and output layers consisted of four and one neurons, respectively. The four inputs were cement, peat, sand content (%) and curing period (days). The simulation results showed efficient performance of the proposed system. The ANFIS and experimental results were compared through the coefficient of determination and root-mean-square error. In conclusion, use of ANFIS network enhances prediction and generation of strength. The simulation results confirmed the effectiveness of the suggested strategies. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Evolution of the Ultrasonic Inspection of Heavy Rotor Forgings Over the Last Decades

    Science.gov (United States)

    Zimmer, A.; Vrana, J.; Meiser, J.; Maximini, W.; Blaes, N.

    2010-02-01

    All types of heavy forgings that are used in energy machine industry, rotor shafts as well as discs, retaining rings or tie bolts are subject to extensive nondestructive inspections before they are delivered to the customer. Due to the availability of the parts in simple shapes, these forgings are very well suited for full volmetric inspections using ultrasound. In the beginning, these inspections were carried out manually, using straight beam probes and analogue equipment. Higher requirements in reliability, efficiency, safety and power output in the machines have lead to higher requirements for the ultrasonic inspection in the form of more scanning directions, higher sensitivity demands and improved documentation means. This and the increasing use of high alloy materials for ever growing parts, increase the need for more and more sophisticated methods for testing the forgings. Angle scans and sizing technologies like DGS have been implemented, and for more than 15 years now, mechanized and automated inspections have gained importance since they allow better documentation as well as easier evaluation of the recorded data using different views (B- C- or D-Scans), projections or tomography views. The latest major development has been the availability of phased array probes to increase the flexibility of the inspection systems. Many results of the ongoing research in ultrasonic's have not been implemented yet. Today's availability of fast computers, large and fast data storages allows saving RF inspection data and applying sophisticated signal processing methods. For example linear diffraction tomography methods like SAFT offer tools for 3D reconstruction of inspection data, simplifying sizing and locating of defects as well as for improving signal to noise ratios. While such methods are already applied in medical ultrasonic's, they are still to be implemented in the steel industry. This paper describes the development of the ultrasonic inspection of heavy forgings

  20. Flexible, transparent and exceptionally high power output nanogenerators based on ultrathin ZnO nanoflakes

    Science.gov (United States)

    van Ngoc, Huynh; Kang, Dae Joon

    2016-02-01

    Novel nanogenerator structures composed of ZnO nanoflakes of less than 10 nm thickness were fabricated using a novel method involving a facile synthetic route and a rational design. The fabricated nanogenerators exhibited a short-circuit current density of 67 μA cm-2, a peak-to-peak open-circuit voltage of 110 V, and an overall output power density exceeding 1.2 mW cm-2, and to the best of our knowledge, these are the best values that have been reported so far in the literature on ZnO-based nanogenerators. We demonstrated that our nanogenerator design could instantaneously power 20 commercial green light-emitting diodes without any additional energy storage processes. Both the facile synthetic route for the ZnO nanoflakes and the straightforward device fabrication process present great scaling potential in order to power mobile and personal electronics that can be used in smart wearable systems, transparent and flexible devices, implantable telemetric energy receivers, electronic emergency equipment, and other self-powered nano/micro devices.Novel nanogenerator structures composed of ZnO nanoflakes of less than 10 nm thickness were fabricated using a novel method involving a facile synthetic route and a rational design. The fabricated nanogenerators exhibited a short-circuit current density of 67 μA cm-2, a peak-to-peak open-circuit voltage of 110 V, and an overall output power density exceeding 1.2 mW cm-2, and to the best of our knowledge, these are the best values that have been reported so far in the literature on ZnO-based nanogenerators. We demonstrated that our nanogenerator design could instantaneously power 20 commercial green light-emitting diodes without any additional energy storage processes. Both the facile synthetic route for the ZnO nanoflakes and the straightforward device fabrication process present great scaling potential in order to power mobile and personal electronics that can be used in smart wearable systems, transparent and flexible

  1. Receive-Noise Analysis of Capacitive Micromachined Ultrasonic Transducers.

    Science.gov (United States)

    Bozkurt, Ayhan; Yaralioglu, G Goksenin

    2016-11-01

    This paper presents an analysis of thermal (Johnson) noise received from the radiation medium by otherwise noiseless capacitive micromachined ultrasonic transducer (CMUT) membranes operating in their fundamental resonance mode. Determination of thermal noise received by multiple numbers of transducers or a transducer array requires the assessment of cross-coupling through the radiation medium, as well as the self-radiation impedance of the individual transducer. We show that the total thermal noise received by the cells of a CMUT has insignificant correlation, and is independent of the radiation impedance, but is only determined by the mass of each membrane and the electromechanical transformer ratio. The proof is based on the analytical derivations for a simple transducer with two cells, and extended to transducers with numerous cells using circuit simulators. We used a first-order model, which incorporates the fundamental resonance of the CMUT. Noise power is calculated by integrating over the entire spectrum; hence, the presented figures are an upper bound for the noise. The presented analyses are valid for a transimpedance amplifier in the receive path. We use the analysis results to calculate the minimum detectable pressure of a CMUT. We also provide an analysis based on the experimental data to show that output noise power is limited by and comparable to the theoretical upper limit.

  2. Ultrasonic evaluation of the physical and mechanical properties of granites.

    Science.gov (United States)

    Vasconcelos, G; Lourenço, P B; Alves, C A S; Pamplona, J

    2008-09-01

    Masonry is the oldest building material that survived until today, being used all over the world and being present in the most impressive historical structures as an evidence of spirit of enterprise of ancient cultures. Conservation, rehabilitation and strengthening of the built heritage and protection of human lives are clear demands of modern societies. In this process, the use of nondestructive methods has become much common in the diagnosis of structural integrity of masonry elements. With respect to the evaluation of the stone condition, the ultrasonic pulse velocity is a simple and economical tool. Thus, the central issue of the present paper concerns the evaluation of the suitability of the ultrasonic pulse velocity method for describing the mechanical and physical properties of granites (range size between 0.1-4.0 mm and 0.3-16.5 mm) and for the assessment of its weathering state. The mechanical properties encompass the compressive and tensile strength and modulus of elasticity, and the physical properties include the density and porosity. For this purpose, measurements of the longitudinal ultrasonic pulse velocity with distinct natural frequency of the transducers were carried out on specimens with different size and shape. A discussion of the factors that induce variations on the ultrasonic velocity is also provided. Additionally, statistical correlations between ultrasonic pulse velocity and mechanical and physical properties of granites are presented and discussed. The major output of the work is the confirmation that ultrasonic pulse velocity can be effectively used as a simple and economical nondestructive method for a preliminary prediction of mechanical and physical properties, as well as a tool for the assessment of the weathering changes of granites that occur during the serviceable life. This is of much interest due to the usual difficulties in removing specimens for mechanical characterization.

  3. The Analysis of the Field Application Methodology of Electromagnetic Ultrasonic Testing for Piping in Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chi Seung; Joo, Keum Jong; Choi, Jung Kweun; Um, Byung Kook; Park, Jea Suk [Korea Advanced Ispection Technology Co., Daejeon (Korea, Republic of)

    2008-08-15

    Nuclear plant piping is classified as the safety class and non-safety class piping in usual. Safety class piping has been examined in accordance with ASME Section XI and V during PSI/ISI using RT, UT, PT, ECT, etc and evaluated periodically for integrity. But failures in piping had reported at non-welded parts and non-safety class pipings as well as the safety class pipings. The existing NDT methods are suitable for the specific parts for instance weldments to inspect but difficult to examine all parts (total coverage) of pipe line and very expensive in cost and consume the time. And also inspection using those methods is difficult and limited for the parts which are complex configuration, embedded under ground and installed at high radiation area in nuclear power plants. In order to inspect all parts of long range piping systems and reduce the inspection time and cost, the electromagnetic ultrasonic inspection technology is suitable and effective. The electromagnetic ultrasonic method can cover more than 50 m apart from sensor at one time without moving the sensor and examined the parts which are in difficulties for accessibility, for example, high radiation area, insulated components and embedded under ground.

  4. Chemical coloring on stainless steel by ultrasonic irradiation.

    Science.gov (United States)

    Cheng, Zuohui; Xue, Yongqiang; Ju, Hongbin

    2018-01-01

    To solve the problems of high temperature and non-uniformity of coloring on stainless steel, a new chemical coloring process, applying ultrasonic irradiation to the traditional chemical coloring process, was developed in this paper. The effects of ultrasonic frequency and power density (sound intensity) on chemical coloring on stainless steel were studied. The uniformity of morphology and colors was observed with the help of polarizing microscope and scanning electron microscopy (SEM), and the surface compositions were characterized by X-ray photoelectric spectroscopy (XPS), meanwhile, the wear resistance and the corrosion resistance were investigated, and the effect mechanism of ultrasonic irradiation on chemical coloring was discussed. These results show that in the process of chemical coloring on stainless steel by ultrasonic irradiation, the film composition is the same as the traditional chemical coloring, and this method can significantly enhance the uniformity, the wear and corrosion resistances of the color film and accelerate the coloring rate which makes the coloring temperature reduced to 40°C. The effects of ultrasonic irradiation on the chemical coloring can be attributed to the coloring rate accelerated and the coloring temperature reduced by thermal-effect, the uniformity of coloring film improved by dispersion-effect, and the wear and corrosion resistances of coloring film enhanced by cavitation-effect. Ultrasonic irradiation not only has an extensive application prospect for chemical coloring on stainless steel but also provides an valuable reference for other chemical coloring. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Variable self-powered light detection CMOS chip with real-time adaptive tracking digital output based on a novel on-chip sensor.

    Science.gov (United States)

    Wang, HongYi; Fan, Youyou; Lu, Zhijian; Luo, Tao; Fu, Houqiang; Song, Hongjiang; Zhao, Yuji; Christen, Jennifer Blain

    2017-10-02

    This paper provides a solution for a self-powered light direction detection with digitized output. Light direction sensors, energy harvesting photodiodes, real-time adaptive tracking digital output unit and other necessary circuits are integrated on a single chip based on a standard 0.18 µm CMOS process. Light direction sensors proposed have an accuracy of 1.8 degree over a 120 degree range. In order to improve the accuracy, a compensation circuit is presented for photodiodes' forward currents. The actual measurement precision of output is approximately 7 ENOB. Besides that, an adaptive under voltage protection circuit is designed for variable supply power which may undulate with temperature and process.

  6. Effects of ultrasonic disintegration on sludge microbial activity and dewaterability

    International Nuclear Information System (INIS)

    Li Huan; Jin Yiying; Mahar, Rasool Bux; Wang Zhiyu; Nie Yongfeng

    2009-01-01

    Ultrasonic treatment can disintegrate sludge, enhance microbial activity and improve sludge dewaterability at different energy inputs. To find their relationship, the three phenomena during ultrasonic treatment were investigated synchronously, and an experimental model was established to describe the process of ultrasonic sludge disintegration. Analysis results showed that the changes of sludge microbial activity and dewaterability were dependent on sludge disintegration degree during ultrasonic treatment. When sludge disintegration degree was lower than 20%, sludge flocs were disintegrated into micro-floc aggregates and the microbial activity increased over 20%. When sludge disintegration degree was over 40%, most cells were destroyed at different degree, and sludge activity decreased drastically. Only when sludge disintegration degree was 2-5%, sludge dewaterability was improved with the conditioning of FeCl 3 . It was also found that the sonication with low density and long duration was more efficient than sonication with high density and short duration at the same energy input for sludge disintegration, and a transmutative power function model can be used to describe the process of ultrasonic disintegration

  7. Effects of ultrasonic disintegration on sludge microbial activity and dewaterability.

    Science.gov (United States)

    Huan, Li; Yiying, Jin; Mahar, Rasool Bux; Zhiyu, Wang; Yongfeng, Nie

    2009-01-30

    Ultrasonic treatment can disintegrate sludge, enhance microbial activity and improve sludge dewaterability at different energy inputs. To find their relationship, the three phenomena during ultrasonic treatment were investigated synchronously, and an experimental model was established to describe the process of ultrasonic sludge disintegration. Analysis results showed that the changes of sludge microbial activity and dewaterability were dependent on sludge disintegration degree during ultrasonic treatment. When sludge disintegration degree was lower than 20%, sludge flocs were disintegrated into micro-floc aggregates and the microbial activity increased over 20%. When sludge disintegration degree was over 40%, most cells were destroyed at different degree, and sludge activity decreased drastically. Only when sludge disintegration degree was 2-5%, sludge dewaterability was improved with the conditioning of FeCl(3). It was also found that the sonication with low density and long duration was more efficient than sonication with high density and short duration at the same energy input for sludge disintegration, and a transmutative power function model can be used to describe the process of ultrasonic disintegration.

  8. Outputs of shock-loaded small piezoceramic disks

    International Nuclear Information System (INIS)

    Charest, Jacques A.; Mace, Jonathan Lee

    2002-01-01

    Thin small-diameter polycrystalline Lead-Zirconate-Titanate piezoceramic disks were shock loaded in the D33 orientation over a stress range of 0.1-30 GPa. Their electrical outputs were discharged into 50 Ω viewing resistors, producing typically 0.15 μs quasi-triangular impulses ranging from 50-700 V. The gas gun flat plate impact approach and the high explosives (HE) plane wave lens approach were used to load piezoceramic elements. These piezoceramic elements consisted of 0.25 mm thick and 1.32 mm diameter disks that were ultrasonically machined from 25 mm piezocrystal disks of type APC 850, commercially produced by American Piezo Ceramic Inc. To facilitate our experiments, the piezoceramic elements were coaxially mounted at the tip of a 2.35 mm diameter brass tube, an arrangement that is commercialized by Dynasen, Inc. under the name Piezopin of model CA-1136. Simple calculations on the electrical outputs produced by these piezoceramic disks reveal electrical outputs in excess of 3000 W. Such short bursts of electrical energy have the potential for numerous applications where critical timing is needed to observe fast transient events

  9. Evaluation of computer-based ultrasonic inservice inspection systems

    International Nuclear Information System (INIS)

    Harris, R.V. Jr.; Angel, L.J.; Doctor, S.R.; Park, W.R.; Schuster, G.J.; Taylor, T.T.

    1994-03-01

    This report presents the principles, practices, terminology, and technology of computer-based ultrasonic testing for inservice inspection (UT/ISI) of nuclear power plants, with extensive use of drawings, diagrams, and LTT images. The presentation is technical but assumes limited specific knowledge of ultrasonics or computers. The report is divided into 9 sections covering conventional LTT, computer-based LTT, and evaluation methodology. Conventional LTT topics include coordinate axes, scanning, instrument operation, RF and video signals, and A-, B-, and C-scans. Computer-based topics include sampling, digitization, signal analysis, image presentation, SAFI, ultrasonic holography, transducer arrays, and data interpretation. An evaluation methodology for computer-based LTT/ISI systems is presented, including questions, detailed procedures, and test block designs. Brief evaluations of several computer-based LTT/ISI systems are given; supplementary volumes will provide detailed evaluations of selected systems

  10. Switching power supplies with multiple isolated output and unitary power factor with an only switch; Fonte chaveada com multiplas saidas isoladas e fator de potencia unitario com um unico interruptor

    Energy Technology Data Exchange (ETDEWEB)

    Canesin, Carlos Alberto

    1990-09-01

    The analysis and implementation of switching power supplies with multiple output, through the use of the D C/D C Single Ended Primary Inductance Converter - SEPIC is presented. The structure has a single switch mode processing stage, improved input power factor, with the use of the variable current hysteresis control, or, constant on time control. The analysis of the D C/D C SEPIC, output characteristics and computer simulation is presented. A switching power supply practical design and experimental results are presented to demonstrate the validity of the theoretical analysis. (author)

  11. Ultrasonic inspection

    International Nuclear Information System (INIS)

    Satittada, Gannaga

    1984-01-01

    Ultrasonic inspection is one of the most widely used methods for nondestructive inspection. The beam of high-frequency sound wave, ultrasonic wave, is introduced into the material. It travels through the material with some attendant loss of energy and can be reflected at interfaces. The reflected beam is detected and analyzed. Ultrasonic inspection is used to detect flaws in metal parts as well as in welded, brazed and bonded joints during research work and developing production and service. It is also used to detect and locate porosity, pipe, and flakes. In addition, it can be used for the measurement of metal thickness. Ultrasonic inspection is therefore used for quality control and material inspection in all major industries

  12. Inter-laboratory comparison of HITU power measurement methods and capabilities

    International Nuclear Information System (INIS)

    Jenderka, K V; Durando, G; Karaboece, B; Rajagopal, S; Shaw, A

    2011-01-01

    High Intensity Therapeutic Ultrasound (HITU) is gaining in importance among the spectrum of therapeutic options to combat cancer. HITU has already been approved and is in clinical use for the treatment of organs like the prostate, the liver and the uterus. Nevertheless, the metrology of the applied high power ultrasound fields, and in consequence, reliable treatment planning and monitoring, is still a challenge. As part of a European Metrology Research Programme project, the four National Metrology Institutes from the UK, Germany, Italy and Turkey conducted an inter-laboratory comparison of their power measurement capabilities at power levels of 5, 25, 75 and 150 W each at frequencies of 1.1, 1.5 and 3.3 MHz. The task was to measure the total, time-averaged ultrasonic output power, emitted by the circulated transducers under specified electrical excitation conditions into an anechoic water load, and the actual rms transducer input voltage. The output value to be reported was the electro-acoustic radiation conductance including the associated standard and expanded uncertainties. Several different measurement techniques were applied to gain further insight into HITU power measurement. The deviations from the calculated comparison reference value found for the different techniques are discussed and conclusions for the further improvement of measuring procedures are drawn.

  13. Inter-laboratory comparison of HITU power measurement methods and capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Jenderka, K V [Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig (Germany); Durando, G [Istituto Nazionale di Ricerca Metrologica (INRIM), Strada delle Cacce 91, 10135 Torino (Italy); Karaboece, B [Tuebitak Ulusal Metroloji Enstituesue (UME), P.K. 54 41470 Gebze-Kocaeli (Turkey); Rajagopal, S; Shaw, A, E-mail: kvjend@ieee.org [National Physical Laboratory (NPL), Hampton Road, Teddington, TW11 0LW (United Kingdom)

    2011-02-01

    High Intensity Therapeutic Ultrasound (HITU) is gaining in importance among the spectrum of therapeutic options to combat cancer. HITU has already been approved and is in clinical use for the treatment of organs like the prostate, the liver and the uterus. Nevertheless, the metrology of the applied high power ultrasound fields, and in consequence, reliable treatment planning and monitoring, is still a challenge. As part of a European Metrology Research Programme project, the four National Metrology Institutes from the UK, Germany, Italy and Turkey conducted an inter-laboratory comparison of their power measurement capabilities at power levels of 5, 25, 75 and 150 W each at frequencies of 1.1, 1.5 and 3.3 MHz. The task was to measure the total, time-averaged ultrasonic output power, emitted by the circulated transducers under specified electrical excitation conditions into an anechoic water load, and the actual rms transducer input voltage. The output value to be reported was the electro-acoustic radiation conductance including the associated standard and expanded uncertainties. Several different measurement techniques were applied to gain further insight into HITU power measurement. The deviations from the calculated comparison reference value found for the different techniques are discussed and conclusions for the further improvement of measuring procedures are drawn.

  14. Integrity and life estimation of turbine runner cover in a hydro power plant

    Directory of Open Access Journals (Sweden)

    A. Sedmak

    2016-03-01

    Full Text Available This paper presents integrity and life estimation of turbine runner cover in a vertical pipe turbines, Kaplan 200 MW nominal output power, produced in Russia, and built in six hydro-generation units of hydroelectric power plant „Đerdap 1” in Serbia. Fatigue and corrosion-fatigue interaction have been taken into account using experimentally obtained material properties, as well as analytical and numerical calculations of stress state, to estimate appropriate safety factors. Fatigue crack growth rate, da/dN, was also calculated, indicated that internal defects of circular or elliptical shape, found out by ultrasonic testing, do not affect reliable operation of runner cover.

  15. A study of the effectiveness and energy efficiency of ultrasonic emulsification.

    Science.gov (United States)

    Li, Wu; Leong, Thomas S H; Ashokkumar, Muthupandian; Martin, Gregory J O

    2017-12-20

    Three essential experimental parameters in the ultrasonic emulsification process, namely sonication time, acoustic amplitude and processing volume, were individually investigated, theoretically and experimentally, and correlated to the emulsion droplet sizes produced. The results showed that with a decrease in droplet size, two kinetic regions can be separately correlated prior to reaching a steady state droplet size: a fast size reduction region and a steady state transition region. In the fast size reduction region, the power input and sonication time could be correlated to the volume-mean diameter by a power-law relationship, with separate power-law indices of -1.4 and -1.1, respectively. A proportional relationship was found between droplet size and processing volume. The effectiveness and energy efficiency of droplet size reduction was compared between ultrasound and high-pressure homogenisation (HPH) based on both the effective power delivered to the emulsion and the total electric power consumed. Sonication could produce emulsions across a broad range of sizes, while high-pressure homogenisation was able to produce emulsions at the smaller end of the range. For ultrasonication, the energy efficiency was higher at increased power inputs due to more effective droplet breakage at high ultrasound intensities. For HPH the consumed energy efficiency was improved by operating at higher pressures for fewer passes. At the laboratory scale, the ultrasound system required less electrical power than HPH to produce an emulsion of comparable droplet size. The energy efficiency of HPH is greatly improved at large scale, which may also be true for larger scale ultrasonic reactors.

  16. Some observations on stray magnetic fields and power outputs from short-wave diathermy equipment

    Energy Technology Data Exchange (ETDEWEB)

    Lau, R.W.M.; Dunscombe, P.B.

    1984-04-01

    Recent years have seen increasing interest in the possible hazards arising from the use of nonionizing electromagnetic radiation. Relatively large and potentially hazardous fields are to be found in the vicinity of short-wave and microwave equipment used in physiotherapy departments to produce therapeutic temperature rises. This note reports the results of measurements of the stray magnetic field and power output of a conventional short-wave diathermy unit when applied to tissue-equivalent phantoms. The dependence of these quantities on the variables, i.e. power setting of the unit, capacitor plate size, phantom size and phantom-capacitor plate separation, are discussed.

  17. Synthesis of strontium substituted barium titanate nanoparticles by mechanical alloying and high power ultrasonication destruction

    Energy Technology Data Exchange (ETDEWEB)

    Yustanti, Erlina, E-mail: erlina.yustanti@ui.ac.id [Graduate Program of Material Science, Faculty of Mathematics and Natural Sciences University of Indonesia Jl. Salemba Raya No. 04 Jakarta 10430 (Indonesia); Department of Metallurgy, Faculty of Engineering University of Sultan AgengTirtayasa Jl. Jenderal Sudirman KM 03 Cilegon-Banten 65134 (Indonesia); Hafizah, Mas Ayu Elita, E-mail: kemasayu@yahoo.com; Manaf, Azwar, E-mail: azwar@ui.ac.id [Graduate Program of Material Science, Faculty of Mathematics and Natural Sciences University of Indonesia Jl. Salemba Raya No. 04 Jakarta 10430 (Indonesia)

    2016-04-19

    This paper reports the particle and crystallite size characterizations of mechanically alloyed Ba{sub (1-x)}Sr{sub x}TiO{sub 3} (BST) with x = 0.3 and 0.7 prepared with the assistance of a high-power sonicator. Analytical grade BaCO{sub 3}, TiO{sub 2} and SrCO{sub 3} precursors with a purity of greater than 99 wt.% were mixed and milled using a planetary ball mill to a powder weight ratio of 10:1. Powders obtained after 20 hours of milling time were then sintered at 1200°C for 4 hours to form crystalline powders.These powders were further treated ultrasonically under a fixed 6.7 gr/l particle concentration in demineralized water for 1, 3, 5, 7 hours and a fixed ultrasonic irradiation time of 1 hour to the dispersion of 6.7; 20; 33.3 gr/l concentrations. As to the results of crystallite size characterization, it is demonstrated that the mean crystallite size of BST with x = 0.3 and 0.7 undergo a slight change after the first 1 hour irradiation time and then remain almost unchanged. This was in contrary to the particle size in which the mean particle size of BST with x = 0.3 increased from 765 nm to 1405 nm after 7 hours irradiation time, while that of x = 0.7 increased from 505 nm to 1298 nm after 3 hours and then reduced back to the initial size after 7 hours ultra sonication time. The increase in particle size was due to large of cohesive forces among fine particles. It is also demonstrated that the concentration of particles in a dispersion with anionic surfactant do not effective to reduce the particle sizes ultrasonically. Nanoparticles with the mean size respectively 40 and 10 times larger than their respective crystallite size were successfully obtained respectively in x = 0.3 and x = 0.7.

  18. Synthesis of strontium substituted barium titanate nanoparticles by mechanical alloying and high power ultrasonication destruction

    International Nuclear Information System (INIS)

    Yustanti, Erlina; Hafizah, Mas Ayu Elita; Manaf, Azwar

    2016-01-01

    This paper reports the particle and crystallite size characterizations of mechanically alloyed Ba (1-x) Sr x TiO 3 (BST) with x = 0.3 and 0.7 prepared with the assistance of a high-power sonicator. Analytical grade BaCO 3 , TiO 2 and SrCO 3 precursors with a purity of greater than 99 wt.% were mixed and milled using a planetary ball mill to a powder weight ratio of 10:1. Powders obtained after 20 hours of milling time were then sintered at 1200°C for 4 hours to form crystalline powders.These powders were further treated ultrasonically under a fixed 6.7 gr/l particle concentration in demineralized water for 1, 3, 5, 7 hours and a fixed ultrasonic irradiation time of 1 hour to the dispersion of 6.7; 20; 33.3 gr/l concentrations. As to the results of crystallite size characterization, it is demonstrated that the mean crystallite size of BST with x = 0.3 and 0.7 undergo a slight change after the first 1 hour irradiation time and then remain almost unchanged. This was in contrary to the particle size in which the mean particle size of BST with x = 0.3 increased from 765 nm to 1405 nm after 7 hours irradiation time, while that of x = 0.7 increased from 505 nm to 1298 nm after 3 hours and then reduced back to the initial size after 7 hours ultra sonication time. The increase in particle size was due to large of cohesive forces among fine particles. It is also demonstrated that the concentration of particles in a dispersion with anionic surfactant do not effective to reduce the particle sizes ultrasonically. Nanoparticles with the mean size respectively 40 and 10 times larger than their respective crystallite size were successfully obtained respectively in x = 0.3 and x = 0.7.

  19. Influence of ultrasonic irradiation on ozone generation in a dielectric barrier discharge

    International Nuclear Information System (INIS)

    Kusano, Y; Drews, J; Leipold, F; Fateev, A; Bardenshtein, A; Krebs, N

    2012-01-01

    An atmospheric pressure dielectric barrier discharge (DBD) was generated in an N 2 /O 2 gas mixture at room temperature with and without ultrasonic irradiation to investigate ozone production. Powerful ultrasonic irradiation with the sound pressure level of approximately 150 dB into the DBD can enhance ozone production especially when the DBD was driven at a frequency of 15 kHz.

  20. The Acute Effect of Upper-Body Complex Training on Power Output of Martial Art Athletes as Measured by the Bench Press Throw Exercise

    Science.gov (United States)

    Liossis, Loudovikos Dimitrios; Forsyth, Jacky; Liossis, Ceorge; Tsolakis, Charilaos

    2013-01-01

    The purpose of this study was to examine the acute effect of upper body complex training on power output, as well as to determine the requisite preload intensity and intra-complex recovery interval needed to induce power output increases. Nine amateur-level combat/martial art athletes completed four distinct experimental protocols, which consisted of 5 bench press repetitions at either: 65% of one-repetition maximum (1RM) with a 4 min rest interval; 65% of 1RM with an 8 min rest; 85% of 1RM with a 4 min rest; or 85% of 1RM with an 8 min rest interval, performed on different days. Before (pre-conditioning) and after (post-conditioning) each experimental protocol, three bench press throws at 30% of 1RM were performed. Significant differences in power output pre-post conditioning were observed across all experimental protocols (F=26.489, partial eta2=0.768, p=0.001). Mean power output significantly increased when the preload stimulus of 65% 1RM was matched with 4 min of rest (p=0.001), and when the 85% 1RM preload stimulus was matched with 8 min of rest (p=0.001). Moreover, a statistically significant difference in power output was observed between the four conditioning protocols (F= 21.101, partial eta2=0.913, p=0.001). It was concluded that, in complex training, matching a heavy preload stimulus with a longer rest interval, and a lighter preload stimulus with a shorter rest interval is important for athletes wishing to increase their power production before training or competition. PMID:24511352

  1. Design of signal reception and processing system of embedded ultrasonic endoscope

    Science.gov (United States)

    Li, Ming; Yu, Feng; Zhang, Ruiqiang; Li, Yan; Chen, Xiaodong; Yu, Daoyin

    2009-11-01

    Embedded Ultrasonic Endoscope, based on embedded microprocessor and embedded real-time operating system, sends a micro ultrasonic probe into coelom through the biopsy channel of the Electronic Endoscope to get the fault histology features of digestive organs by rotary scanning, and acquires the pictures of the alimentary canal mucosal surface. At the same time, ultrasonic signals are processed by signal reception and processing system, forming images of the full histology of the digestive organs. Signal Reception and Processing System is an important component of Embedded Ultrasonic Endoscope. However, the traditional design, using multi-level amplifiers and special digital processing circuits to implement signal reception and processing, is no longer satisfying the standards of high-performance, miniaturization and low power requirements that embedded system requires, and as a result of the high noise that multi-level amplifier brought, the extraction of small signal becomes hard. Therefore, this paper presents a method of signal reception and processing based on double variable gain amplifier and FPGA, increasing the flexibility and dynamic range of the Signal Reception and Processing System, improving system noise level, and reducing power consumption. Finally, we set up the embedded experiment system, using a transducer with the center frequency of 8MHz to scan membrane samples, and display the image of ultrasonic echo reflected by each layer of membrane, with a frame rate of 5Hz, verifying the correctness of the system.

  2. Three-dimensional analyses of ultrasonic scaler oscillations.

    Science.gov (United States)

    Lea, Simon C; Felver, Bernhard; Landini, Gabriel; Walmsley, A Damien

    2009-01-01

    It is stated that the oscillation patterns of dental ultrasonic scalers are dependent upon whether the instrument is of a magnetostrictive or piezoelectric design. These patterns are then linked to differences in root surface debridement in vitro. Piezoelectric (A, P) and magnetostrictive (Slimline, TFI-3) ultrasonic scalers (three of each) were evaluated, loaded (100 g/200 g) and unloaded with a 3D laser vibrometer. Loads were applied to the probe tips via teeth mounted in a load-measuring device. Elliptical motion was demonstrated for all probes under loaded and unloaded conditions. Loading flattened the elliptical motion along the length of the probe. Unloaded, Slimline tip 1 was significantly different to tips 2 and 3 (p0.207). All TFI-3 tips were different to each other (p0.867). Generator power increased all Slimline and P tip vibrations (pultrasound production mechanism and are dependent upon probe shape and generator power. Loaded probes oscillated with an elliptical pattern.

  3. Applications of ultrasonic phased array technique during fabrication of nuclear tubing and other components for the Indian nuclear power program

    International Nuclear Information System (INIS)

    Kapoor, K.

    2015-01-01

    Ultrasonic phased array technique has been applied in fabrication of nuclear fuel and structural at NFC. The integrity of the nuclear fuel and structural components is most crucial as they are exposed to severe environment during operation leading to rapid degradation of its properties during its lifecycle. Nuclear Fuel Complex has mandate for the fabrication of the nuclear fuel and core structurals for Indian PHWRs/BWR, sub-assemblies for the PFBR and steam generator tubing for PFBR and PHWRs which are the most critical materials for the Indian Nuclear Power program. NDE during fabrication of these materials is thus most crucial as it provides the confidence to the designer for safe operation during its lifetime. Many of these techniques have to be developed in-house to meet unique requirements of high sensitivity, resolution and shape of the components. Some of the advancements in the NDE during the fabrication include use of ultrasonic phased array which is detailed in this paper

  4. Coupling/Tradeoff Analysis and Novel Containment Control for Reactive Power, Output Voltage in Islanded Micro-Grid

    DEFF Research Database (Denmark)

    Han, Renke; Meng, Lexuan; Guerrero, Josep M.

    2016-01-01

    Based on the hierarchical control structure in islanded Micro-Grid (MG) systems, the coupling/tradeoff effects in different control levels are analyzed in details. In the primary level, analyses of the coupling effects among droop control gains, line impedance differences, output reactive power...

  5. Energetic balance in an ultrasonic reactor using focused or flat high frequency transducers.

    Science.gov (United States)

    Hallez, L; Touyeras, F; Hihn, J Y; Klima, J

    2007-09-01

    In order to undertake irradiation of polymer blocks or films by ultrasound, this paper deals with the measurements of ultrasonic power and its distribution within the cell by several methods. The electric power measured at the transducer input is compared to the ultrasonic power input to the cell evaluated by calorimetry and radiation force measurement for different generator settings. Results obtained in the specific case of new transducer types (composites and focused composites i.e., HIFU: high intensity focused ultrasound) provide an opportunity to conduct a discussion about measurement methods. It has thus been confirmed that these measurement techniques can be applied to HIFU transducers. For all cases, results underlined the fact that measurement of radiation pressure for power evaluation is more adapted to low powers (generator-transducer-liquid and sample.

  6. Influence of the level of fit of a density probability function to wind-speed data on the WECS mean power output estimation

    Energy Technology Data Exchange (ETDEWEB)

    Carta, Jose A. [Department of Mechanical Engineering, University of Las Palmas de Gran Canaria, Campus de Tafira s/n, 35017 Las Palmas de Gran Canaria, Canary Islands (Spain); Ramirez, Penelope; Velazquez, Sergio [Department of Renewable Energies, Technological Institute of the Canary Islands, Pozo Izquierdo Beach s/n, 35119 Santa Lucia, Gran Canaria, Canary Islands (Spain)

    2008-10-15

    Static methods which are based on statistical techniques to estimate the mean power output of a WECS (wind energy conversion system) have been widely employed in the scientific literature related to wind energy. In the static method which we use in this paper, for a given wind regime probability distribution function and a known WECS power curve, the mean power output of a WECS is obtained by resolving the integral, usually using numerical evaluation techniques, of the product of these two functions. In this paper an analysis is made of the influence of the level of fit between an empirical probability density function of a sample of wind speeds and the probability density function of the adjusted theoretical model on the relative error {epsilon} made in the estimation of the mean annual power output of a WECS. The mean power output calculated through the use of a quasi-dynamic or chronological method, that is to say using time-series of wind speed data and the power versus wind speed characteristic of the wind turbine, serves as the reference. The suitability of the distributions is judged from the adjusted R{sup 2} statistic (R{sub a}{sup 2}). Hourly mean wind speeds recorded at 16 weather stations located in the Canarian Archipelago, an extensive catalogue of wind-speed probability models and two wind turbines of 330 and 800 kW rated power are used in this paper. Among the general conclusions obtained, the following can be pointed out: (a) that the R{sub a}{sup 2} statistic might be useful as an initial gross indicator of the relative error made in the mean annual power output estimation of a WECS when a probabilistic method is employed; (b) the relative errors tend to decrease, in accordance with a trend line defined by a second-order polynomial, as R{sub a}{sup 2} increases. (author)

  7. Performance demonstration experience for reactor pressure vessel shell ultrasonic testing

    International Nuclear Information System (INIS)

    Zado, V.

    1998-01-01

    The most ultrasonic testing techniques used by many vendors for pressurized water reactor (PWR) examinations were based on American Society of Mechanical Engineers 'Boiler and Pressurized Vessel Code' (ASME B and PV Code) Sections XI and V. The Addenda of ASME B and PV Code Section XI, Edition 1989 introduced Appendix VIII - 'Performance Demonstration for Ultrasonic Examination Systems'. In an effort to increase confidence in performance of ultrasonic testing of the operating nuclear power plants in United States, the ultrasonic testing performance demonstration examination of reactor vessel welds is performed in accordance with Performance Demonstration Initiative (PDI) program which is based on ASME Code Section XI, Appendix VIII requirements. This article provides information regarding extensive qualification preparation works performed prior EPRI guided performance demonstration exam of reactor vessel shell welds accomplished in January 1997 for the scope of Appendix VIII, Supplements IV and VI. Additionally, an overview of the procedures based on requirements of ASME Code Section XI and V in comparison to procedure prepared for Appendix VIII examination is given and discussed. The samples of ultrasonic signals obtained from artificial flaws implanted in vessel material are presented and results of ultrasonic testing are compared to actual flaw sizes. (author)

  8. OPTIMATION OF 48 KHZ ULTRASONIC WAVE DOSE FOR THE INACTIVATION OF SALMONELLA TYPHI

    Directory of Open Access Journals (Sweden)

    Dwi May Lestari

    2015-01-01

    Full Text Available This study was aimed to determine the effect of ultrasonic dose exposure which could decrease the viability of Salmonella typhi by using the variation of exposure time (15, 20, 25, and 30 minutes and volume of bacterial suspension (2, 4, 6, and 8 ml at constant power. The sample used was Salmonella typhi. Ultrasonic wave transmitter was a piezoelectric tweeter with 0,191 watts of power and 48 kHz frequency generated by the signal generator. Piezoelectric tweeter was a kind of transducer which converted electrical energy into ultrasonic energy. This research was an experimental laboratory with a completely randomized design. The decrease of bacterial percentage was calculated by using TPC (Total Plate Count. Data were analyzed by using One Way Anova. The results showed that the variation of exposure time and volume of bacterial suspension gave significant effect on the percentage of Salmonella typhi kill. The most optimal of ultrasonic dose exposure to kill Salmonella typhi was 281.87 J/ml with 100% bacterial kill.

  9. Effects of ultrasonic assisted cooking on the chemical profiles of taste and flavor of spiced beef.

    Science.gov (United States)

    Zou, Yunhe; Kang, Dacheng; Liu, Rui; Qi, Jun; Zhou, Guanghong; Zhang, Wangang

    2018-09-01

    The objective of this study was to assess the effects of ultrasonic assisted cooking on the chemical profiles of spiced beef taste and flavor. Ultrasound power with 0 W, 400 W, 600 W, 800 W and 1000 W (frequency of 20 kHz) were used for cooking 120 min. The sodium chloride, sugar, free amino acids (FAAs), 5'-ribonucleotides, lipid oxidation, volatile flavor substance contents and electronic nose of spiced beef were determined. Results showed that ultrasonic treatment could significantly increase the content of sodium chloride in beef sample (P  0.05). With the ultrasonic treatment, the types and relative content of volatile flavor substances were significantly increased (P alcohols and ketones. However, there was no significant variation among the different ultrasound power groups (P > 0.05). This result was consistent with the measurement of electronic nose. Data points of control samples were away from ultrasonic treatment groups, while data points of different ultrasonic treatment groups were flock together. The results indicate that the application of ultrasound during cooking has a positive effect on chemical profiles of spiced beef taste and flavor, particularly for the power of 800 W. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. A study on the repeatability of ultrasonic testing data

    International Nuclear Information System (INIS)

    Yoshimura, Seiichi; Fukumoto, Hiroshi

    1980-01-01

    Reliability improvement of ultrasonic testing data is strongly desired in ultrasonic testing working of nuclear power plants. This paper deals with the problems of the testing by the manual and the remote control apparatus, and with the factors which influence the repeatability of ultrasonic testing data. Following results are found in it. (1) In the testing by the manual, working time and posture influence the repeatability of testing data. (2) Glycerin in suitable for the couplant in the respect of the repeatability of testing data. In the case of using machine oil, the pressure to the probe necessitates to be over 0.2 kg/cm 2 . (3) In the testing by the remote control apparatus, working time, working environment and defect position does not influence the repeatability of testing data. (author)

  11. Modeling the ultrasonic testing echoes by a combination of particle swarm optimization and Levenberg–Marquardt algorithms

    International Nuclear Information System (INIS)

    Gholami, Ali; Honarvar, Farhang; Moghaddam, Hamid Abrishami

    2017-01-01

    This paper presents an accurate and easy-to-implement algorithm for estimating the parameters of the asymmetric Gaussian chirplet model (AGCM) used for modeling echoes measured in ultrasonic nondestructive testing (NDT) of materials. The proposed algorithm is a combination of particle swarm optimization (PSO) and Levenberg–Marquardt (LM) algorithms. PSO does not need an accurate initial guess and quickly converges to a reasonable output while LM needs a good initial guess in order to provide an accurate output. In the combined algorithm, PSO is run first to provide a rough estimate of the output and this result is consequently inputted to the LM algorithm for more accurate estimation of parameters. To apply the algorithm to signals with multiple echoes, the space alternating generalized expectation maximization (SAGE) is used. The proposed combined algorithm is robust and accurate. To examine the performance of the proposed algorithm, it is applied to a number of simulated echoes having various signal to noise ratios. The combined algorithm is also applied to a number of experimental ultrasonic signals. The results corroborate the accuracy and reliability of the proposed combined algorithm. (paper)

  12. Endurance training decreases the non-linearity in the oxygen uptake-power output relationship in humans.

    Science.gov (United States)

    Majerczak, Joanna; Korostynski, Michal; Nieckarz, Zenon; Szkutnik, Zbigniew; Duda, Krzysztof; Zoladz, Jerzy A

    2012-03-01

    In this study, we hypothesized that 5 weeks of cycling endurance training can decrease the magnitude of the non-proportional increase in oxygen uptake (V(O(2))) to power output relationship (V(O(2)) 'excess') at exercise intensities exceeding the lactate threshold (LT). Ten untrained, physically active men performed a bout of incremental cycling exercise until exhaustion before and after training. The mitochondrial DNA copy number, myosin heavy chain composition and content of uncoupling protein 3 and sarcoplasmic reticulum Ca(2+)-ATPases (SERCAs) were analysed in muscle biopsies taken from vastus lateralis before and after training. The training resulted in an enhancement of the power-generating capabilities at maximal oxygen uptake (V(O(2)max)) by ∼7% (P = 0.002) despite there being no changes in V(O(2)max) (P = 0.49). This effect was due to a considerable reduction in the magnitude of the V(O(2)) 'excess' (P 0.05) were found after training. We conclude that the training-induced increase in power-generating capabilities at V(O(2)max) was due to attenuation of the V(O(2)) 'excess' above the LT. This adaptive response seems to be related to the improvement of muscle metabolic stability, as judged by a lowering of plasma ammonia concentration. The enhancement of muscle metabolic stability after training could be caused by a decrease in ATP usage at a given power output owing to downregulation of SERCA2 pumps.

  13. A capacitive ultrasonic transducer based on parametric resonance.

    Science.gov (United States)

    Surappa, Sushruta; Satir, Sarp; Levent Degertekin, F

    2017-07-24

    A capacitive ultrasonic transducer based on a parametric resonator structure is described and experimentally demonstrated. The transducer structure, which we call capacitive parametric ultrasonic transducer (CPUT), uses a parallel plate capacitor with a movable membrane as part of a degenerate parametric series RLC resonator circuit with a resonance frequency of f o . When the capacitor plate is driven with an incident harmonic ultrasonic wave at the pump frequency of 2f o with sufficient amplitude, the RLC circuit becomes unstable and ultrasonic energy can be efficiently converted to an electrical signal at f o frequency in the RLC circuit. An important characteristic of the CPUT is that unlike other electrostatic transducers, it does not require DC bias or permanent charging to be used as a receiver. We describe the operation of the CPUT using an analytical model and numerical simulations, which shows drive amplitude dependent operation regimes including parametric resonance when a certain threshold is exceeded. We verify these predictions by experiments with a micromachined membrane based capacitor structure in immersion where ultrasonic waves incident at 4.28 MHz parametrically drive a signal with significant amplitude in the 2.14 MHz RLC circuit. With its unique features, the CPUT can be particularly advantageous for applications such as wireless power transfer for biomedical implants and acoustic sensing.

  14. Ultrasonic treatment of Viscozyme Cassava C preparation for improving cellulase activity

    Science.gov (United States)

    Tra, Tran Thi Thu; Vu, Huynh Minh; Man, Le Van Viet

    2017-09-01

    In this study, the effects of ultrasonic treatment on the cellulolytic activity of Viscozyme Cassava C preparation were investigated. The biocatalyst was treated with ultrasound at different enzyme concentrations (from 0.02 to 19.50 mg protein/mL), ultrasonic powers (from 0 to 12 W/mL) and times (from 0 to 120 seconds). The highest cellulase activity was achieved when the enzyme preparation was ultrasonicated at 7.3 W/mL for 40 sec, under which the cellulase activity increased by 18.1% over the control. The optimal pH and temperature of the sonicated and unsonicated biocatalysts were statistically similar. However, the half-life value of the sonicated preparation at 4 °C was 24.5% higher than that of the unsonicated preparation. This result indicated that ultrasonic treatment of the enzyme preparation could reduce its amount used in biocatalysis.

  15. Ultrasonic process for destruction of chlorinated organic compounds in aqueous solution

    International Nuclear Information System (INIS)

    Wu, Jiann M.; Huang, Hann S.

    1993-01-01

    Laboratory investigations of the ultrasonic process for destruction of low concentrations of carbon tetrachloride (CCl 4 ) into nonhazardous end products were carried out in a bench-scale batch reactor, equipped with a 600-W ultrasonic power supply. Process parameters studied included irradiation time, concentration, steady-state operating temperature, pH, and the intensity of applied ultrasonic-wave energy. High destruction efficiencies of greater than 99% were achieved through this process, and the irradiation time and the intensity of applied energy were identified to be the most important process parameters. The irradiation time required for a given degree of destruction decreased with increasing intensity of the applied ultrasonic energy. In addition, a detailed chemical reaction mechanism for the destruction of CCl 4 in water was formulated. The agreement between the model and experimental results is generally good

  16. Cutting efficiency of apical preparation using ultrasonic tips with microprojections: confocal laser scanning microscopy study.

    Science.gov (United States)

    Kwak, Sang-Won; Moon, Young-Mi; Yoo, Yeon-Jee; Baek, Seung-Ho; Lee, WooCheol; Kim, Hyeon-Cheol

    2014-11-01

    The purpose of this study was to compare the cutting efficiency of a newly developed microprojection tip and a diamond-coated tip under two different engine powers. The apical 3-mm of each root was resected, and root-end preparation was performed with upward and downward pressure using one of the ultrasonic tips, KIS-1D (Obtura Spartan) or JT-5B (B&L Biotech Ltd.). The ultrasonic engine was set to power-1 or -4. Forty teeth were randomly divided into four groups: K1 (KIS-1D / Power-1), J1 (JT-5B / Power-1), K4 (KIS-1D / Power-4), and J4 (JT-5B / Power-4). The total time required for root-end preparation was recorded. All teeth were resected and the apical parts were evaluated for the number and length of cracks using a confocal scanning micrscope. The size of the root-end cavity and the width of the remaining dentin were recorded. The data were statistically analyzed using two-way analysis of variance and a Mann-Whitney test. There was no significant difference in the time required between the instrument groups, but the power-4 groups showed reduced preparation time for both instrument groups (p < 0.05). The K4 and J4 groups with a power-4 showed a significantly higher crack formation and a longer crack irrespective of the instruments. There was no significant difference in the remaining dentin thickness or any of the parameters after preparation. Ultrasonic tips with microprojections would be an option to substitute for the conventional ultrasonic tips with a diamond coating with the same clinical efficiency.

  17. Ultrasonic mammography

    International Nuclear Information System (INIS)

    Hueneke, B.

    1982-01-01

    608 women are examined by means of ultrasonic mammography during the period of 1 year. 432 patients were examined with the compound method with the U.I. Octoson, a water tank scanner, and 176 patients with the real time method with a directly connected linear-array-scanner. The following results were obtained at the end of the examination period: In the ultrasonic and also in the X-ray mammogram tumour diameters can be determined with an error rate of +- 30%. In the diagnosing of carcinomas, a significant dependence of the exactness on the sice of the tumour is found for the combination of the five methods tested (clinical examination, X-ray mammography, ultrasonic mammography, thermography, cytology). Classifying the individual methods with regard to their exactness, X-ray mammography ranks in front of ultrasonic mammography. Mastopathic changes in the breast can be screened by means of ultrasonic mammography. The structure of the changes can be determined more exactly than with an X-ray picture which is due to the possibility of differentiating solid and cystic structures. In diagnosing fibro-adenomas and establishing diagnoses on young women with dense gland bodies, ultrasonic mammography is superior to radiology both in the ability of screening a finding of a fibro-adenoma (US=88%, X-ray=75%) and in the possibility of classifying it as ''more benign than malignant''. (orig./MG) [de

  18. Grain structure, texture and mechanical property evolution of automotive aluminium sheet during high power ultrasonic welding

    International Nuclear Information System (INIS)

    Haddadi, Farid; Tsivoulas, Dimitrios

    2016-01-01

    High power ultrasonic spot welding (HPUSW) is a joining technique which is performed within less than a second and provides a more energy-efficient alternative to friction stir spot welding (FSSW), which is considered a longer cycle manufacturing process for joining automotive alloys. To date, only a few reports exist on the deformation mechanisms that take place during high power ultrasonic spot welding. In this work, dynamic recrystallization and grain growth were examined using electron backscatter diffraction (EBSD). HPUSW causes extensive deformation within the weld zone where the temperature increases to 440 °C. An ultra-fine grain structure was observed in a thin band of flat weld interface within a short welding time of 0.10 s. With increasing welding time the interface was displaced and ‘folds’ or ‘crests’ appeared together with shear bands. The weld interface progressively changed from flat to sinusoidal and eventually to a convoluted wave-like pattern when the tool fully penetrated the workpiece, having a wavelength of ~ 1 mm after 0.40 s. Finally, the microstructure and texture varied significantly depending on the location within the weld. Although the texture near the weld interface was relatively weak, a shift was observed with increasing welding time from an initially Cube-dominated texture to one where the typical β-fibre Brass component prevailed. - Highlights: •Lap shear strength of ~2.9 kN was achieved in 0.30 sec welding time. •Temperature approached 440 °C along the weld centreline for the highest welding time. •The texture near the teeth was dominated by Brass, P and S components at optimum condition. •The weld interface showed typical β-fibre deformation texture at optimum condition.

  19. Grain structure, texture and mechanical property evolution of automotive aluminium sheet during high power ultrasonic welding

    Energy Technology Data Exchange (ETDEWEB)

    Haddadi, Farid, E-mail: farid.haddadi@gmail.com [Clemson University–International Center for Automotive Research (CU-ICAR), #347, 4 Research Drive, Greenville, SC 29607 (United States); School of Materials, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Tsivoulas, Dimitrios, E-mail: dim.tsivoulas@gmail.com [School of Materials, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Clean Energy/Nuclear Services, Amec Foster Wheeler, 601 Faraday Street, Birchwood Park, Warrington WA3 6GN (United Kingdom)

    2016-08-15

    High power ultrasonic spot welding (HPUSW) is a joining technique which is performed within less than a second and provides a more energy-efficient alternative to friction stir spot welding (FSSW), which is considered a longer cycle manufacturing process for joining automotive alloys. To date, only a few reports exist on the deformation mechanisms that take place during high power ultrasonic spot welding. In this work, dynamic recrystallization and grain growth were examined using electron backscatter diffraction (EBSD). HPUSW causes extensive deformation within the weld zone where the temperature increases to 440 °C. An ultra-fine grain structure was observed in a thin band of flat weld interface within a short welding time of 0.10 s. With increasing welding time the interface was displaced and ‘folds’ or ‘crests’ appeared together with shear bands. The weld interface progressively changed from flat to sinusoidal and eventually to a convoluted wave-like pattern when the tool fully penetrated the workpiece, having a wavelength of ~ 1 mm after 0.40 s. Finally, the microstructure and texture varied significantly depending on the location within the weld. Although the texture near the weld interface was relatively weak, a shift was observed with increasing welding time from an initially Cube-dominated texture to one where the typical β-fibre Brass component prevailed. - Highlights: •Lap shear strength of ~2.9 kN was achieved in 0.30 sec welding time. •Temperature approached 440 °C along the weld centreline for the highest welding time. •The texture near the teeth was dominated by Brass, P and S components at optimum condition. •The weld interface showed typical β-fibre deformation texture at optimum condition.

  20. Piezoelectric ultrasonic micromotor with 1.5 mm diameter.

    Science.gov (United States)

    Dong, Shuxiang; Lim, Siak P; Lee, Kwork H; Zhang, Jingdong; Lim, Leong C; Uchino, Kenji

    2003-04-01

    A piezoelectric ultrasonic micromotor has been developed using a lead zirconate titanate (PZT) ceramic/metal composite tube stator that was 1.5 mm in diameter and 7 mm in length. The micromotor was operated in its first bending vibration mode (approximately 70 kHz), producing speeds from hundreds to over 2000 rpm in both rotational directions. The maximum torque-output was 45 microN-m, which is far superior to previous PZT thin film-based micromotors. This micromotor showed good reliability and stability for more than 300 hours of continued operation.

  1. Ultrasonic physics

    CERN Document Server

    Richardson, E G

    1962-01-01

    Ultrasonic Physics, Second Edition, provides an introduction to the fundamental principles of ultrasonic physics. The book opens with a discussion of the sources of ultrasound. This is followed by separate chapters on the properties and detection of ultrasonic radiation; measurement of propagation constants, i.e., the velocity and absorption, of ultrasound; ultrasound propagation in gases, liquids, and solids; and ultrasound propagation in aerosols, suspensions, and emulsions. The final chapter covers miscellaneous physical and physico-chemical actions, including dispersion and coagulation of

  2. Ultrasonic defect detection method for socket welding joint

    International Nuclear Information System (INIS)

    Tominaga, Masaaki; Matsuo, Toshiyuki; Ueno, Akihiro; Watanabe, Kunimichi; Kawamata, Kunio.

    1995-01-01

    The present invention provides a method of detecting defects over a wide range of a socket weld portion of various kinds of pipelines used, for example, in a nuclear power plant. Namely, an inclined probe is disposed to a jig for detecting defects by ultrasonic waves. This is rotated at least by one turn along the peripheral surface of the material to be detected such as weld tube joints. Defects of weld portion of the material can be detected automatically by using ultrasonic waves during the rotation. The inclined probe for detecting defects by ultrasonic waves comprises a transmission portion having a planar transmittance oscillator disposed to a wedge on the transmission side and a receiving portion comprising a planar receiving oscillator disposed to a wedge on the receiving side. With such a constitution, ultrasonic waves are emitted from the transmission portion to the defect detection portion in the welded portion. If a defect is present, defective echo is reflected to the receiving portion disposed ahead of the probe. Since the defective echo changes depending on the height of the detective portion, the estimation of the height of the defect can be facilitated. (I.S.)

  3. Contactless ultrasonic energy transfer for wireless systems: acoustic-piezoelectric structure interaction modeling and performance enhancement

    International Nuclear Information System (INIS)

    Shahab, S; Erturk, A

    2014-01-01

    There are several applications of wireless electronic components with little or no ambient energy available to harvest, yet wireless battery charging for such systems is still of great interest. Example applications range from biomedical implants to sensors located in hazardous environments. Energy transfer based on the propagation of acoustic waves at ultrasonic frequencies is a recently explored alternative that offers increased transmitter-receiver distance, reduced loss and the elimination of electromagnetic fields. As this research area receives growing attention, there is an increased need for fully coupled model development to quantify the energy transfer characteristics, with a focus on the transmitter, receiver, medium, geometric and material parameters. We present multiphysics modeling and case studies of the contactless ultrasonic energy transfer for wireless electronic components submerged in fluid. The source is a pulsating sphere, and the receiver is a piezoelectric bar operating in the 33-mode of piezoelectricity with a fundamental resonance frequency above the audible frequency range. The goal is to quantify the electrical power delivered to the load (connected to the receiver) in terms of the source strength. Both the analytical and finite element models have been developed for the resulting acoustic-piezoelectric structure interaction problem. Resistive and resistive–inductive electrical loading cases are presented, and optimality conditions are discussed. Broadband power transfer is achieved by optimal resistive-reactive load tuning for performance enhancement and frequency-wise robustness. Significant enhancement of the power output is reported due to the use of a hard piezoelectric receiver (PZT-8) instead of a soft counterpart (PZT-5H) as a result of reduced material damping. The analytical multiphysics modeling approach given in this work can be used to predict and optimize the coupled system dynamics with very good accuracy and

  4. [Research on ultrasonic permeability of low intensity pulsed ultrasound through PTFE membrane and Bio-Gide collagen membrane].

    Science.gov (United States)

    Chai, Zhaowu; Zhao, Chunliang; Song, Jinlin; Deng, Feng; Yang, Ji; Gao, Xiang; Liu, Minyi

    2013-12-01

    The aim of the present study was to detect the transmission rate of ultrasonic low intensity pulsed ultrasound (LIPUS) through polytetrafluoroethylene (PTFE) membrane (Thickness: 0.01 mm) and Bio-Gide collagen membrane, and to provide the basis for the barrier membrane selection on the study of LIPUS combined with guided tissue regeneration (GTR). The ultrasonic (LIPUS, frequency 1.5 MHz, pulse width 200 micros, repetition rate 1.0 kHz) transmission coefficient of the two kinds of barrier membrane were detected respectively through setting ten groups from 10 to 100mW/cm2 every other 10 mW/cm2. We found in the study that the ultrasonic transmission coefficient through 0.01 mm PTFE membrane was 78.1% to 92.%, and the ultrasonic transmission coefficient through Bio-Gide collagen membrane was 43.9% to 55.8%. The ultrasonic transmission coefficient through PTFE membrane was obviously higher than that through Bio-Gide collagen membrane. The transmission coefficient of the same barrier membrane of the ultrasonic ion was statistically different under different powers (P PTFE membrane and Bio-Gide collagen membrane were relatively high. We should select barrier membranes based on different experimental needs, and exercise ultrasonic transmission coefficient experiments to ensure effective power.

  5. Stirling converters for space dynamic power concepts with 2 to 130 We output

    International Nuclear Information System (INIS)

    Ross, B.A.

    1995-01-01

    Three innovative Stirling converter concepts are described. Two concepts are based on Pluto Fast Flyby (PFF) mission requirements, where two General Purpose Heat Source (GPHS) modules provide the thermal input. The first concept (PFF2) considers a power system with two opposed Stirling converters; the second concept (PFF4) considers four opposed Stirling converters. For both concepts the Stirling converters are designed to vary their power production capability to compensate for the failure of one Stirling converter. While the net thermal efficiency of PFF4 is a few percentage points lower than PFF2, the total Stirling converter mass of PFF4 is half that for PFF2. The third concept (ITTI) is designed to supply 2 watts of power for weather stations on the Martian surface. The predicted thermal performance of the ITTI is low compared to PFF2 and PFF4, yet the ITTI concept offers significant advantages compared to currently available power systems at the 2-watt power level. All three concepts are based on long-life technology demonstrated by an 11-watt output Stirling generator that as of March 1995 has accumulated over 15,000 operating hours without maintenance

  6. Embedded fiber optic ultrasonic sensors and generators

    Science.gov (United States)

    Dorighi, John F.; Krishnaswamy, Sridhar; Achenbach, Jan D.

    1995-04-01

    Ultrasonic sensors and generators based on fiber-optic systems are described. It is shown that intrinsic fiber optic Fabry-Perot ultrasound sensors that are embedded in a structure can be stabilized by actively tuning the laser frequency. The need for this method of stabilization is demonstrated by detecting piezoelectric transducer-generated ultrasonic pulses in the presence of low frequency dynamic strains that are intentionally induced to cause sensor drift. The actively stabilized embedded fiber optic Fabry-Perot sensor is also shown to have sufficient sensitivity to detect ultrasound that is generated in the interior of a structure by means of a high-power optical fiber that pipes energy from a pulsed laser to an embedded generator of ultrasound.

  7. The Effect of the Number of Sets on Power Output for Different Loads

    Science.gov (United States)

    Morales-Artacho, Antonio J.; Padial, Paulino; García-Ramos, Amador; Feriche, Belén

    2015-01-01

    There is much debate concerning the optimal load (OL) for power training. The purpose of this study was to investigate the effect of the number of sets performed for a given load on mean power output (Pmean). Fourteen physically active men performed 3 sets of 3 bench-press repetitions with 30, 40 and 50 kg. The highest mean power value (Pmax) across all loads and Pmean were compared when data were taken from the first set at each absolute load vs. from the best of three sets performed. Pmean increased from the first to the third set (from 5.99 ± 0.81 to 6.16 ± 0.96 W·kg−1, p = 0.017), resulting in a main effect of the set number (p 0.05). Pmax and velocity were significantly affected by the method employed to determine Pmean at each load (p < 0.05). These results show a positive effect of the number of sets per load on Pmean, affecting Pmax, OL and potentially power training prescription. PMID:26240658

  8. The Effect of the Number of Sets on Power Output for Different Loads

    Directory of Open Access Journals (Sweden)

    Morales-Artacho Antonio J.

    2015-06-01

    Full Text Available There is much debate concerning the optimal load (OL for power training. The purpose of this study was to investigate the effect of the number of sets performed for a given load on mean power output (Pmean. Fourteen physically active men performed 3 sets of 3 bench-press repetitions with 30, 40 and 50 kg. The highest mean power value (Pmax across all loads and Pmean were compared when data were taken from the first set at each absolute load vs. from the best of three sets performed. Pmean increased from the first to the third set (from 5.99 ± 0.81 to 6.16 ± 0.96 W·kg−1, p = 0.017, resulting in a main effect of the set number (p 0.05. Pmax and velocity were significantly affected by the method employed to determine Pmean at each load (p < 0.05. These results show a positive effect of the number of sets per load on Pmean, affecting Pmax, OL and potentially power training prescription.

  9. Ultrasonic downcomer flow measurements for recirculating steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Janzen, Victor, E-mail: Victor.Janzen@cnl.ca [Canadian Nuclear Laboratories, Chalk River, ON, Canada K0 J 1J0 (Canada); Luloff, Brian [Canadian Nuclear Laboratories, Chalk River, ON, Canada K0 J 1J0 (Canada); Sedman, Ken [Nuclear Safety Analysis & Support Department, Bruce Power, Toronto, ON, Canada M5G 1X6 (Canada)

    2015-08-15

    Highlights: • Measuring recirculating flow in nuclear steam generators provides useful information. • Flow measurements shed light on component performance and degradation mechanisms. • Commonly used ultrasonic technology and application methods are described. • Results of measurements at several power reactors are summarized. • Potential improvements in reliability and flexibility of application are suggested. - Abstract: Measurements of downcomer flow in nuclear steam generators can provide unique fitness for service and performance indicators related to overall thermalhydraulic performance, safety related secondary-side setpoints and certain forms of degradation. This paper reviews the benefits of downcomer-flow measurements to nuclear power–plant operators, and describes methods that are commonly used. It summarizes the history and state-of-the-art of the most widely used technology, non-intrusive ultrasonic systems, including field applications at several nuclear power plants. It also describes the technical challenges that remain, and summarizes recent technical developments and future improvements.

  10. A Study on a Crack Evaluation Technique for Turbine Blade Root Using Phased Array Ultrasonics

    International Nuclear Information System (INIS)

    Cho, Yong Sang; Jung, Gye Jo; Park, Sang Ki; Kim, Jae Hoon

    2004-01-01

    Ultrasonic testing is a kind of nondestructive test to detect a crack or discontinuity in materials or on material surfaces by sending ultrasound to it. This conventional ultrasonic technique has some limitations in reliably detecting crack or accurately assessing materials in the case of complex-shaped power plant components such as a turbine blade root. An alternative method for such a difficult inspection is highly needed. In this study, application of a phased array ultrasonic testing (UT) system to a turbine blade, one of the critical power plant components, has been considered, and the particular incident angle has been determined so that the greatest track detectability and the most accurate crack length evaluation nay be achieved. The response of ultrasonic phased array was also analyzed to establish a special method to determine the track length without moving the transducer. The result showed that the developed method for crack length assessment is a more accurate and effective method, compared with the conventional method

  11. Mode Identification of Guided Ultrasonic Wave using Time- Frequency Algorithm

    International Nuclear Information System (INIS)

    Yoon, Byung Sik; Yang, Seung Han; Cho, Yong Sang; Kim, Yong Sik; Lee, Hee Jong

    2007-01-01

    The ultrasonic guided waves are waves whose propagation characteristics depend on structural thickness and shape such as those in plates, tubes, rods, and embedded layers. If the angle of incidence or the frequency of sound is adjusted properly, the reflected and refracted energy within the structure will constructively interfere, thereby launching the guided wave. Because these waves penetrate the entire thickness of the tube and propagate parallel to the surface, a large portion of the material can be examined from a single transducer location. The guided ultrasonic wave has various merits like above. But various kind of modes are propagating through the entire thickness, so we don't know the which mode is received. Most of applications are limited from mode selection and mode identification. So the mode identification is very important process for guided ultrasonic inspection application. In this study, various time-frequency analysis methodologies are developed and compared for mode identification tool of guided ultrasonic signal. For this study, a high power tone-burst ultrasonic system set up for the generation and receive of guided waves. And artificial notches were fabricated on the Aluminum plate for the experiment on the mode identification

  12. Study on the sandwich piezoelectric ceramic ultrasonic transducer in thickness vibration

    International Nuclear Information System (INIS)

    Lin Shuyu; Tian Hua

    2008-01-01

    A sandwich piezoelectric ceramic ultrasonic transducer in thickness vibration is studied. The transducer consists of front and back metal masses, and coaxially segmented, thickness polarized piezoelectric ceramic thin rings. For this kind of sandwich piezoelectric transducers in thickness vibration, it is required that the lateral dimension of the transducer is sufficiently large compared with its longitudinal dimension so that no lateral displacements in the transducer can occur (laterally clamped). In this paper, the thickness vibration of the piezoelectric ceramic stack consisting of a number of identical piezoelectric ceramic thin rings is analysed and its electro-mechanical equivalent circuit is obtained. The resonance frequency equation for the sandwich piezoelectric ceramic ultrasonic transducer in thickness vibration is derived. Based on the frequency equation, two sandwich piezoelectric ceramic ultrasonic transducers are designed and manufactured, and their resonance frequencies are measured. It is shown that the measured resonance frequencies are in good agreement with the theoretical results. This kind of sandwich piezoelectric ultrasonic transducer is expected to be used in megasonic ultrasonic cleaning and sonochemistry where high power and high frequency ultrasound is needed

  13. Output characteristics of 40 kW photovoltaic power generation system in ICT; Ibaraki kosen ni okeru 40 kW taiyoko hatsuden shisutemu no shutsuryoku tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Sekiguchi, N. [Ibaraki National College of Tech., Ibaraki (Japan); Tani, T. [Science University of Tokyo, Tokyo (Japan)

    1999-11-25

    The photovoltaic power generation system consists of photovoltaic array and power conditioner of the utility connected system. The photovoltaic array parallelly constitutes 18 serial 30 of the modules of 540 sheets, and there is the generating capacity of largest 40 kW. The power conditioner uses 10 kW four units, and it is tracking with function of the maximum output point. This report examined the unconformable rate of photovoltaic array maximum output operating voltage, current and power in simulation and power conditioner input. (author)

  14. A neural network approach to local downscaling of GCM output for assessing wind power implications of climate change

    International Nuclear Information System (INIS)

    Sailor, D.J.; Hu, T.; Li, X.; Rosen, J.N.

    2000-01-01

    A methodology is presented for downscaling General Circulation Model (GCM) output to predict surface wind speeds at scales of interest in the wind power industry under expected future climatic conditions. The approach involves a combination of Neural Network tools and traditional weather forecasting techniques. A Neural Network transfer function is developed to relate local wind speed observations to large scale GCM predictions of atmospheric properties under current climatic conditions. By assuming the invariability of this transfer function under conditions of doubled atmospheric carbon dioxide, the resulting transfer function is then applied to GCM output for a transient run of the National Center for Atmospheric Research coupled ocean-atmosphere GCM. This methodology is applied to three test sites in regions relevant to the wind power industry - one in Texas and two in California. Changes in daily mean wind speeds at each location are presented and discussed with respect to potential implications for wind power generation. (author)

  15. Fatigue fracture of steel after mechanical and ultrasonic strengthening

    International Nuclear Information System (INIS)

    Stotskij, I.M.

    1978-01-01

    Fatigue fracture surfaces of samples after mechanical and ultrasonic strengthening have been studied metallographically and by electron fractography. Studied was the 40Kh steel hardened from 850 deg and then tempered at 180 deg or at 550 deg C. The ultrasound power was 25 kWt, the frequency was 20 kHz, the sample rotation velocity was 39.5 m/min. Mechanical and ultrasonic treatment was found to cause structural changes (formation of a white layer) and deformation of the material under the layer. The fatigue cracks were extending beyond the white layer; their propagation involved generation and coalescence of microcracks on account of segregation of carbides. It is concluded that mechanical and ultrasonic treatment should be used for increasing the fatigue strength of low and average strength materials rather than hardened or low-tempered ones

  16. Performance investigation on the ultrasonic atomization liquid desiccant regeneration system

    International Nuclear Information System (INIS)

    Yang, Zili; Zhang, Kaisheng; Hwang, Yunho; Lian, Zhiwei

    2016-01-01

    Highlights: • We applied ultrasonic atomization technology to boost liquid desiccant regeneration. • We established a novel UARS and made a thorough study on its performance. • We developed a performance prediction model for UARS and validated its accuracy. • The necessary regeneration temperature dropped significantly (4.4 °C) in UARS. • Energy consumption for regenerating desiccant was reduced greatly (60.4%) in UARS. - Abstract: Liquid desiccant dehumidification systems have accumulated considerable research interest in recent years for their great energy saving potential in buildings. Within the system, the regenerator recovering liquid desiccant plays a major role in its performance. When the ultrasonic atomization technology is applied to atomize the desiccant solution into numerous tiny droplets with diameters around 50 μm, the regeneration process could be greatly enhanced. To validate this approach, a novel ultrasonic atomization liquid desiccant regeneration system (UARS) was studied in this work. An Ideal Regeneration Model (IRM) was developed to predict the regeneration performance of the UARS. Additionally, thorough experiments were carried out to validate the model under different operating conditions of the desiccant solution and air stream. The model predicted values and the experimental results coincided, with the average deviation less than 7.9%. The performance of UARS was compared with other regeneration systems from the open literature, while a case study was conducted for the power consumption and energy saving potential of UARS. It was found that the ultrasonic atomization technology enabled utilization of lower-grade energy for desiccant regeneration with the regeneration temperature lowered as much as 4.4 °C. In addition, a considerable energy saving potential of up to 23.4% could be achieved by the UARS for regenerating per unit mass flow of desiccant solution, while the power consumption of the ultrasonic atomization system

  17. Ultrasonic-assisted extraction and in vitro antioxidant activity of polysaccharides from Agaricus bisporus.

    Science.gov (United States)

    Qiao, De-Liang; Zhao, Feng; Huang, Hai-Zhong; Fan, Chun-Chun; Han, Lei

    2012-08-01

    To optimize ultrasonic-assisted extraction parameters of polysaccharides from Agaricus bisporus and evaluate antioxidant activities of A. bisporus polysaccharides. Polysaccharides from A. bisporus was extracted by using methods of ultrasonic-assisted hot water lixiviation, ethanol precipitation, Sevag's deproteination and ethanol precipitation again. Extraction temperature, extraction time, ratio of water to raw material and ultrasonic power were selected in single-factor tests. Based on the single-factor tests, parameters combination for the ultrasonic-assisted extraction of A. bisporus polysaccharides was optimized by using four-factor-three-level orthogonal test. Antioxidant activities (reductive potential, superoxide anion scavenging activity and H2O2 scavenging activity) of A. bisporus polysaccharides were evaluated in vitro. Optimum conditions for the extracting of A. bisporus polysaccharides were extracting temperature 65 degrees C, extracting time 40 min, ratio of water to raw material 30 mL/g and ultrasonic power 170 w. Practicing this optimal condition, extraction yield of polysaccharides from A. bisporus was 5.6 014%. In crude polysaccharides of A. bisporus, carbohydrates content, determined by applying the phenol-sulfuric acid method, was 75.48%. Polysaccharides of A. bisporus could reduce ferric ion, scavenge superoxide anion and hydrogen peroxide in a dose-dependent manner. Utrasonic-assisted extraction could be used in the extracting of A. bisporus polysaccharides. Polysaccharides of A. bisporus, had direct and potent antioxidant activities, might be developed and utilized as natural antioxidant.

  18. Capacitor current feedback for output filter damping in switched-mode magnet power supplies

    International Nuclear Information System (INIS)

    Paven Kumar, M.R.; Kim, J.M.S.

    1994-01-01

    In magnet power supplies for a particle accelerator system, a second-order low-pass filter is used to reduce the output current ripple content within specifications. The output filter must be properly damped in order to avoid any large amplification at the resonant frequency and large transient responses of voltages and currents at the step change of the line voltage. Conventionally, a series combination of resistance and capacitance is added in parallel with the filter capacitor to provide the required damping. This approach, however, requires a large dc-blocking capacitor which has to be several times larger than the filter capacitor. In this paper, a filter damping technique using capacitor current feedback is presented. The basic concept of the capacitor current feedback is established using a linear model of the converter involved, and then a sampled-data model of the converter is used to analyze the filter damping technique. The filter damping effect of the capacitor current feedback is verified experimentally

  19. Effect of Ultrasonic Frequency on Lactic Acid Fermentation Promotion by Ultrasonic Irradiation

    Science.gov (United States)

    Shimada, Tadayuki; Ohdaira, Etsuzo; Masuzawa, Nobuyoshi

    2004-05-01

    The authors have been researching the promotion of lactic acid fermentation by ultrasonic irradiation. In the past research, it was proven that ultrasonic irradiation is effective in the process of fermentation, and the production of yoghurt and kefir was promoted. In this study, the effect of the ultrasonic frequency in this fermentation process was examined. In the frequency range of this study, it was found that the action of fermentation promotion was exponentially proportionate to the irradiated ultrasonic frequency.

  20. Cutting efficiency of apical preparation using ultrasonic tips with microprojections: confocal laser scanning microscopy study

    Directory of Open Access Journals (Sweden)

    Sang-Won Kwak

    2014-11-01

    Full Text Available Objectives The purpose of this study was to compare the cutting efficiency of a newly developed microprojection tip and a diamond-coated tip under two different engine powers. Materials and Methods The apical 3-mm of each root was resected, and root-end preparation was performed with upward and downward pressure using one of the ultrasonic tips, KIS-1D (Obtura Spartan or JT-5B (B&L Biotech Ltd.. The ultrasonic engine was set to power-1 or -4. Forty teeth were randomly divided into four groups: K1 (KIS-1D / Power-1, J1 (JT-5B / Power-1, K4 (KIS-1D / Power-4, and J4 (JT-5B / Power-4. The total time required for root-end preparation was recorded. All teeth were resected and the apical parts were evaluated for the number and length of cracks using a confocal scanning micrscope. The size of the root-end cavity and the width of the remaining dentin were recorded. The data were statistically analyzed using two-way analysis of variance and a Mann-Whitney test. Results There was no significant difference in the time required between the instrument groups, but the power-4 groups showed reduced preparation time for both instrument groups (p < 0.05. The K4 and J4 groups with a power-4 showed a significantly higher crack formation and a longer crack irrespective of the instruments. There was no significant difference in the remaining dentin thickness or any of the parameters after preparation. Conclusions Ultrasonic tips with microprojections would be an option to substitute for the conventional ultrasonic tips with a diamond coating with the same clinical efficiency.

  1. Electromagnetic ultrasonic guided waves

    CERN Document Server

    Huang, Songling; Li, Weibin; Wang, Qing

    2016-01-01

    This book introduces the fundamental theory of electromagnetic ultrasonic guided waves, together with its applications. It includes the dispersion characteristics and matching theory of guided waves; the mechanism of production and theoretical model of electromagnetic ultrasonic guided waves; the effect mechanism between guided waves and defects; the simulation method for the entire process of electromagnetic ultrasonic guided wave propagation; electromagnetic ultrasonic thickness measurement; pipeline axial guided wave defect detection; and electromagnetic ultrasonic guided wave detection of gas pipeline cracks. This theory and findings on applications draw on the author’s intensive research over the past eight years. The book can be used for nondestructive testing technology and as an engineering reference work. The specific implementation of the electromagnetic ultrasonic guided wave system presented here will also be of value for other nondestructive test developers.

  2. Local and regional effects of large scale atmospheric circulation patterns on winter wind power output in Western Europe

    Science.gov (United States)

    Zubiate, Laura; McDermott, Frank; Sweeney, Conor; O'Malley, Mark

    2014-05-01

    Recent studies (Brayshaw, 2009, Garcia-Bustamante, 2010, Garcia-Bustamante, 2013) have drawn attention to the sensitivity of wind speed distributions and likely wind energy power output in Western Europe to changes in low-frequency, large scale atmospheric circulation patterns such as the North Atlantic Oscillation (NAO). Wind speed variations and directional shifts as a function of the NAO state can be larger or smaller depending on the North Atlantic region that is considered. Wind speeds in Ireland and the UK for example are approximately 20 % higher during NAO + phases, and up to 30 % lower during NAO - phases relative to the long-term (30 year) climatological means. By contrast, in southern Europe, wind speeds are 15 % lower than average during NAO + phases and 15 % higher than average during NAO - phases. Crucially however, some regions such as Brittany in N.W. France have been identified in which there is negligible variability in wind speeds as a function of the NAO phase, as observed in the ERA-Interim 0.5 degree gridded reanalysis database. However, the magnitude of these effects on wind conditions is temporally and spatially non-stationary. As described by Comas-Bru and McDermott (2013) for temperature and precipitation, such non-stationarity is caused by the influence of two other patterns, the East Atlantic pattern, (EA), and the Scandinavian pattern, (SCA), which modulate the position of the NAO dipole. This phenomenon has also implications for wind speeds and directions, which has been assessed using the ERA-Interim reanalysis dataset and the indices obtained from the PC analysis of sea level pressure over the Atlantic region. In order to study the implications for power production, the interaction of the NAO and the other teleconnection patterns with local topography was also analysed, as well as how these interactions ultimately translate into wind power output. The objective is to have a better defined relationship between wind speed and power

  3. Hydrogen preheating through waste heat recovery of an open-cathode PEM fuel cell leading to power output improvement

    International Nuclear Information System (INIS)

    Mohamed, W.A.N.W.; Kamikl, M. Haziq M.

    2016-01-01

    Highlights: • A study on the effect of hydrogen preheating using waste heat for low temperature PEM fuel cells. • Theoretical, experimental and analytical framework was established. • The maximum electrical power output increases by 8–10% under specific operating conditions. • Open loop hydrogen supply gives a better performance than closed loop. • The waste heat utilization is less than 10% due to heat capacity limitations. - Abstract: The electrochemical reaction kinetics in a Polymer Electrolyte Membrane (PEM) fuel cell is highly influenced by the reactants supply pressures and electrode temperatures. For an open cathode PEM fuel cell stack, the power output is constrained due to the use of air simultaneously as reactant and coolant. Optimal stack operation temperatures are not achieved especially at low to medium power outputs. Based on the ideal gas law, higher reactant temperatures would lead to higher pressures and subsequently improve the reaction kinetics. The hydrogen supply temperature and its pressure can be increased by preheating; thus, slightly offsetting the limitation of low operating stack temperatures. The exit air stream offers an internal source of waste heat for the hydrogen preheating purpose. In this study, a PEM open-cathode fuel cell was used to experimentally evaluate the performance of hydrogen preheating based on two waste heat recovery approaches: (1) open-loop and (2) closed loop hydrogen flow. The stack waste heat was channelled into a heat exchanger to preheat the hydrogen line before it is being supplied (open loop) or resupplied (closed loop) into the stack. At a constant 0.3 bar hydrogen supply pressure, the preheating increases the hydrogen temperature in the range of 2–13 °C which was dependant on the stack power output and cathode air flow rates. The achievable maximum stack power was increased by 8% for the closed loop and 10% for the open loop. Due to the small hydrogen flow rates, the waste heat utilization

  4. Measurement and visualization of file-to-wall contact during ultrasonically activated irrigation in simulated canals

    NARCIS (Netherlands)

    Boutsioukis, C.; Verhaagen, B.; Walmsley, A.D.; Versluis, Michel; van der Sluis, L.W.M.

    2013-01-01

    Aim (i) To quantify in a simulated root canal model the file-to-wall contact during ultrasonic activation of an irrigant and to evaluate the effect of root canal size, file insertion depth, ultrasonic power, root canal level and previous training, (ii) To investigate the effect of file-to-wall

  5. Measurement and visualization of file-to-wall contact during ultrasonically activated irrigation in simulated canals

    NARCIS (Netherlands)

    Boutsioukis, C.; Verhaagen, B.; Walmsley, A. D.; Versluis, M.; van der Sluis, L. W. M.

    2013-01-01

    Aim(i) To quantify in a simulated root canal model the file-to-wall contact during ultrasonic activation of an irrigant and to evaluate the effect of root canal size, file insertion depth, ultrasonic power, root canal level and previous training, (ii) To investigate the effect of file-to-wall

  6. Long-Range Piping Inspection by Ultrasonic Guided Waves

    International Nuclear Information System (INIS)

    Joo, Young Sang; Lim, Sa Hoe; Eom, Heung Seop; Kim, Jae Hee

    2005-01-01

    The ultrasonic guided waves are very promising for the long-range inspection of large structures because they can propagate a long distance along the structures such as plates, shells and pipes. The guided wave inspection could be utilized for an on-line monitoring technique when the transmitting and receiving transducers are positioned at a remote point on the structure. The received signal has the information about the integrity of the monitoring area between the transmitting and receiving transducers. On-line monitoring of a pipe line using an ultrasonic guided wave can detect flaws such as corrosion, erosion and fatigue cracking at an early stage and collect useful information on the flaws. However the guided wave inspection is complicated by the dispersive characteristics for guided waves. The phase and group velocities are a function of the frequency-thickness product. Therefore, the different frequency components of the guided waves will travel at different speeds and the shape of the received signal will changed as it propagates along the pipe. In this study, we analyze the propagation characteristics of guided wave modes in a small diameter pipe of nuclear power plant and select the suitable mode for a long-range inspection. And experiments will be carried out for the practical application of a long-range inspection in a 26m long pipe by using a high-power ultrasonic inspection system

  7. Ultrasonic viewing device

    International Nuclear Information System (INIS)

    Ito, Juro.

    1979-01-01

    Purpose: To improve the safety of reactor operation by enabling to detect the states and positions of fuel assemblies over a wide range with a set of ultrasonic viewing device comprising a rotatable ultrasonic transmitter-receiver and a reflector mounted with an adjustable angle. Constitution: A driving portion for a ultrasonic viewing device is provided to a rotary plug closing the opening of a reactor vessel and a guide pipe suspending below the coolant level is provided to the driving portion. An ultrasonic transmitter-receiver is provided at the end of the holder tube in the guide pipe. A reflector is provided at the upper position of the reactor core so as to correspond to the ultrasonic transmitter-receiver. The ultrasonic transmitter-receiver, positioned by the driving portion, performs horizontal movement for scanning the entire surface of the top of the reactor core, as well as vertical movement covering the gap between the upper mechanism on the reactor and the reactor core, whereby the confirmation for the separation of the control rod and the detection for the states of the reactor core can be conducted by the reflection waves from the reflector. (Moriyama, K.)

  8. Looking Below the Surface with Ultrasonic Phased Array

    International Nuclear Information System (INIS)

    Cinson, Anthony D.; Crawford, Susan L.

    2010-01-01

    This article is a brief tutorial on the benefits of volumetric ultrasonic phased array line scanning. The article describes the need, the approach, and the methods/practices used to analyze the data for flaw detection and characterization in the nuclear power plant component arena. If you are inspecting the integrity of nuclear power plant components during a scheduled outage, time is likely against you. Time is a luxury that most inspectors do not possess in their daily jobs. They are required to quickly and efficiently perform nondestructive testing (NDT) on various components within the nuclear power plant facility. In addition to the obvious financial impacts ($1M+ per day) of prolonging planned outages, time constraints also are put in place for the safety and health of the inspectors. For instance, while working in highly radioactive or contaminated environments of the plant, inspectors have a limited window of time to volumetrically inspect components for flaws, such as cracks, defects or other anomalies that might lead to leakage or failure during operation. In the interest of simplicity, flaws are limited to cracks for our purposes. Ultrasonic phased array volumetric line scanning is emerging as a powerful tool that allows for quick inspections of components that had been very time-consuming using earlier technologies.

  9. Automated ultrasonic shop inspection of reactor pressure vessel forgings

    International Nuclear Information System (INIS)

    Farley, J.M.; Dikstra, B.J.; Hanstock, D.J.; Pople, C.H.

    1986-01-01

    Automated ultrasonic shop inspection utilizing a computer-controlled system is being applied to each of the forgings for the reactor pressure vessel of the proposed Sizewell B PWR power station. Procedures which utilize a combination of high sensitivity shear wave pulse echo, 0 degrees and 70 degrees angled longitudinal waves, tandem and through-thickness arrays have been developed to provide comprehensive coverage and an overall reliability of inspection comparable to the best achieved in UKAEA defect detection trials and in PISC II. This paper describes the ultrasonic techniques, the automated system (its design, commissioning and testing), validation and the progress of the inspections

  10. Mode control in a high gain relativistic klystron amplifier with 3 GW output power

    Science.gov (United States)

    Wu, Yang; Xie, Hong-Quan; Xu, Zhou

    2014-01-01

    Higher mode excitation is very serious in the relativistic klystron amplifier, especially for the high gain relativistic amplifier working at tens of kilo-amperes. The mechanism of higher mode excitation is explored in the PIC simulation and it is shown that insufficient separation of adjacent cavities is the main cause of higher mode excitation. So RF lossy material mounted on the drift tube wall is adopted to suppress higher mode excitation. A high gain S-band relativistic klystron amplifier is designed for the beam current of 13 kA and the voltage of 1 MV. PIC simulation shows that the output power is 3.2 GW when the input power is only 2.8 kW.

  11. Instantaneous input electrical power measurements of HITU transducer

    International Nuclear Information System (INIS)

    Karaboece, B; Guelmez, Y; Rajagapol, S; Shaw, A

    2011-01-01

    HITU (High Intensity Theraupetic Ultrasound) transducers are widely used in therapeutic ultrasound in medicine. The output ultrasonic power of HITU transducer can be measured in number of methods described in IEC 61161 standard [1]. New IEC standards specifically for measurement of HITU equipment are under development. The ultrasound power radiated from a transducer is dependent on applied input electrical voltage and current and consequently power. But, up to now, no standardised method has been developed and adopted for the input electrical power measurements. Hence, a workpackage was carried out for the establishment of such method in the frequency range of 1 to 3 MHz as a part of EURAMET EMRP Era-net plus 'External Beam Cancer Therapy' project. Several current shunts were developed and evaluated. Current measurements were also realized with Philips current probe and preamplifier at NPL and Agilent current probe at UME. In this paper, a method for the measurement of instantaneous electrical power delivered to a reactive ultrasound transducer in the required frequency range is explored.

  12. Instantaneous input electrical power measurements of HITU transducer

    Energy Technology Data Exchange (ETDEWEB)

    Karaboece, B; Guelmez, Y [Tuebitak Ulusal Metroloji Enstituesue (UME), P.K. 54 41470 Gebze-Kocaeli (Turkey); Rajagapol, S; Shaw, A, E-mail: baki.karaboce@ume.tubitak.gov.t [National Physical Laboratory (NPL), Hampton Road, Teddington TW11 0LW (United Kingdom)

    2011-02-01

    HITU (High Intensity Theraupetic Ultrasound) transducers are widely used in therapeutic ultrasound in medicine. The output ultrasonic power of HITU transducer can be measured in number of methods described in IEC 61161 standard [1]. New IEC standards specifically for measurement of HITU equipment are under development. The ultrasound power radiated from a transducer is dependent on applied input electrical voltage and current and consequently power. But, up to now, no standardised method has been developed and adopted for the input electrical power measurements. Hence, a workpackage was carried out for the establishment of such method in the frequency range of 1 to 3 MHz as a part of EURAMET EMRP Era-net plus 'External Beam Cancer Therapy' project. Several current shunts were developed and evaluated. Current measurements were also realized with Philips current probe and preamplifier at NPL and Agilent current probe at UME. In this paper, a method for the measurement of instantaneous electrical power delivered to a reactive ultrasound transducer in the required frequency range is explored.

  13. Single-transverse-mode near-IR superluminescent diodes with cw output power up to 100 mW

    Energy Technology Data Exchange (ETDEWEB)

    Andreeva, E V; Il' chenko, S N; Kostin, Yu O [Superlum Diodes Ltd., Moscow (Russian Federation); Yakubovich, S D [Moscow State Institute of Radio-Engineering, Electronics and Automation (Technical University), Moscow (Russian Federation)

    2014-10-29

    A series of light-emitting modules based on single-mode quantum-well superluminescent diodes with centre emission wavelengths of about 790, 840, 960 and 1060 nm and a cw output power up to 100 mW in free space is developed. A sufficiently long service life of these devices is demonstrated. (lasers)

  14. Single-transverse-mode near-IR superluminescent diodes with cw output power up to 100 mW

    International Nuclear Information System (INIS)

    Andreeva, E V; Il'chenko, S N; Kostin, Yu O; Yakubovich, S D

    2014-01-01

    A series of light-emitting modules based on single-mode quantum-well superluminescent diodes with centre emission wavelengths of about 790, 840, 960 and 1060 nm and a cw output power up to 100 mW in free space is developed. A sufficiently long service life of these devices is demonstrated. (lasers)

  15. Radial vibration and ultrasonic field of a long tubular ultrasonic radiator.

    Science.gov (United States)

    Shuyu, Lin; Zhiqiang, Fu; Xiaoli, Zhang; Yong, Wang; Jing, Hu

    2013-09-01

    The radial vibration of a metal long circular tube is studied analytically and its electro-mechanical equivalent circuit is obtained. Based on the equivalent circuit, the radial resonance frequency equation is derived. The theoretical relationship between the radial resonance frequency and the geometrical dimensions is studied. Finite element method is used to simulate the radial vibration and the radiated ultrasonic field and the results are compared with those from the analytical method. It is concluded that the radial resonance frequency for a solid metal rod is larger than that for a metal tube with the same outer radius. The radial resonance frequencies from the analytical method are in good agreement with those from the numerical method. Based on the acoustic field analysis, it is concluded that the long metal tube with small wall thickness is superior to that with large wall thickness in producing radial vibration and ultrasonic radiation. Therefore, it is expected to be used as an effective radial ultrasonic radiator in ultrasonic sewage treatment, ultrasonic antiscale and descaling and other ultrasonic liquid handling applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Measurement and visualization of file-to-wall contact during ultrasonically activated irrigation in simulated canals.

    Science.gov (United States)

    Boutsioukis, C; Verhaagen, B; Walmsley, A D; Versluis, M; van der Sluis, L W M

    2013-11-01

    (i) To quantify in a simulated root canal model the file-to-wall contact during ultrasonic activation of an irrigant and to evaluate the effect of root canal size, file insertion depth, ultrasonic power, root canal level and previous training, (ii) To investigate the effect of file-to-wall contact on file oscillation. File-to-wall contact was measured during ultrasonic activation of the irrigant performed by 15 trained and 15 untrained participants in two metal root canal models. Results were analyzed by two 5-way mixed-design anovas. The level of significance was set at P root canal (P root canal (P irrigant activation. Therefore, the term 'Passive Ultrasonic Irrigation' should be amended to 'Ultrasonically Activated Irrigation'. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  17. Preparation of biodiesel with the help of ultrasonic and hydrodynamic cavitation.

    Science.gov (United States)

    Ji, Jianbing; Wang, Jianli; Li, Yongchao; Yu, Yunliang; Xu, Zhichao

    2006-12-22

    An alkali-catalyzed biodiesel production method with power ultrasonic (19.7 kHz) has been developed that allows a short reaction time and high yield because of emulsification and cavitation of the liquid-liquid immiscible system. Orthogonality experiments were employed to evaluate the effects of synthesis parameters. Furthermore, hydrodynamic cavitation was used for biodiesel production in comparison to ultrasonic method. Both methods were proved to be efficient, and time and energy saving for the preparation of biodiesel by transesterification of soybean oil.

  18. Estimation of Scatterer Diameter by Normalized Power Spectrum of High-Frequency Ultrasonic RF Echo for Assessment of Red Blood Cell Aggregation

    Science.gov (United States)

    Fukushima, Taku; Hasegawa, Hideyuki; Kanai, Hiroshi

    2011-07-01

    Red blood cell (RBC) aggregation, as one of the determinants of blood viscosity, plays an important role in blood rheology, including the condition of blood. RBC aggregation is induced by the adhesion of RBCs when the electrostatic repulsion between RBCs weakens owing to increases in protein and saturated fatty acid levels in blood, excessive RBC aggregation leads to various circulatory diseases. This study was conducted to establish a noninvasive quantitative method for assessment of RBC aggregation. The power spectrum of ultrasonic RF echoes from nonaggregating RBCs, which shows the frequency property of scattering, exhibits Rayleigh behavior. On the other hand, ultrasonic RF echoes from aggregating RBCs contain the components of reflection, which have no frequency dependence. By dividing the measured power spectrum of echoes from RBCs in the lumen by that of echoes from a posterior wall of the vein in the dorsum manus, the attenuation property of the propagating medium and the frequency responses of transmitting and receiving transducers are removed from the former spectrum. RBC aggregation was assessed by the diameter of a scatterer, which was estimated by minimizing the square difference between the measured normalized power spectrum and the theoretical power spectrum. In this study, spherical scatterers with diameters of 5, 11, 15, and 30 µm were measured in basic experiments. The estimated scatterer diameters were close to the actual diameters. Furthermore, the transient change of the scatterer diameters were measured in an in vivo experiment with respect to a 24-year-old healthy male during the avascularization using a cuff. The estimated diameters (12-22 µm) of RBCs during avascularization were larger than the diameters (4-8 µm) at rest and after recirculation. These results show the possibility of the use of the proposed method for noninvasive assessment of RBC aggregation.

  19. Ultrasonic testing device

    International Nuclear Information System (INIS)

    Lawrie, W.E.

    1978-01-01

    The ultrasonic transmitter made of polarized ferroelectric ceramic material (lead zirconate titanate) is arranged in a strip carrier which allows it to be introduced between the fuel elements of a fuel subassembly in a water cooled nuclear reactor. The ultrasonic transmitter is insulated relative to the carrier. The echo of the ra dal ultrasonic pulse is recorded which changes as faulty water filled fuel elements are detected. (RW) [de

  20. Thin disk laser with unstable resonator and reduced output coupler

    Science.gov (United States)

    Gavili, Anwar; Shayganmanesh, Mahdi

    2018-05-01

    In this paper, feasibility of using unstable resonator with reduced output coupling in a thin disk laser is studied theoretically. Unstable resonator is modeled by wave-optics using Collins integral and iterative method. An Yb:YAG crystal with 250 micron thickness is considered as a quasi-three level active medium and modeled by solving rate equations of energy levels populations. The amplification of laser beam in the active medium is calculated based on the Beer-Lambert law and Rigrod method. Using generalized beam parameters method, laser beam parameters like, width, divergence, M2 factor, output power as well as near and far-field beam profiles are calculated for unstable resonator. It is demonstrated that for thin disk laser (with single disk) in spite of the low thickness of the disk which leads to low gain factor, it is possible to use unstable resonator (with reduced output coupling) and achieve good output power with appropriate beam quality. Also, the behavior of output power and beam quality versus equivalent Fresnel number is investigated and optimized value of output coupling for maximum output power is achieved.

  1. A computer-controlled electronic system for the ultrasonic NDT of components for nuclear power stations

    International Nuclear Information System (INIS)

    Rehrmann, M.; Harbecke, D.

    1987-01-01

    The paper describes an automatic ultrasonic testing system combined with a computer-controlled electronics system, called IMPULS I, for the non-destructive testing of components of nuclear reactors. The system can be used for both in-service inspection and for inspection during the manufacturing process. IMPUL I has more functions and less components than conventional ultrasonic systems, and the system gives good reproducible test results and is easy to operate. (U.K.)

  2. Time reversal for ultrasonic transcranial surgery and echographic imaging

    Science.gov (United States)

    Tanter, Mickael; Aubry, Jean-Francois; Vignon, Francois; Fink, Mathias

    2005-09-01

    High-intensity focused ultrasound (HIFU) is able to induce non-invasively controlled and selective destruction of tissues by focusing ultrasonic beams within organs, analogous to a magnifying glass that concentrates enough sunlight to burn a hole in paper. The brain is an attractive organ in which to perform ultrasonic tissue ablation, but such an application has been hampered by the strong defocusing effect of the skull bone. Our group has been involved in this topic for several years, providing proofs of concept and proposing technological solutions to this problem. Thanks to a high-power time-reversal mirror, presented here are in vivo thermal lesions induced through the skull of 12 sheep. Thermal lesions were confirmed by T2-weighted magnetic resonance post-treatment images and histological examination. These results provide striking evidence that noninvasive ultrasound brain surgery is feasible. A recent approach for high-resolution brain ultrasonic imaging will also be discussed with a skull aberration correction technique based on twin arrays technology. The correction of transcranial ultrasonic images is implemented on a new generation of time-reversal mirrors relying on a fully programmable transmit and receive beamformer.

  3. Monitoring Low-Cycle Fatigue Material-Degradation by Ultrasonic Methods

    Directory of Open Access Journals (Sweden)

    R. Himawan

    2010-08-01

    Full Text Available Any system consisting of structural material often undergoes fatigue, which is caused by dynamic load cycle. As a structural system, nuclear power plant is very likely to have low-cycle fatigue at many of its components. Taking into account the importance of monitoring low-cycle fatigue on structural components to prevent them from getting failure, the authors have conducted a work to monitor material degradation caused by low-cycle fatigue by using ultrasonic method. An alloy of Cu-40Zn was used as a test specimen. Ultrasonic water immersion procedure was employed in this ultrasonic test. The probe used is a focusing type and has frequency as high as 15 MHz. The specimen area tested is in the middle part divided into 14 points × 23 points. The results, which were frequency spectrums, were analyzed using two parameters: frequency spectrum peak intensity and attenuation function gradient. The analysis indicates that peak intensity increases at the beginning of load cycle and then decreases. Meanwhile, gradient of attenuation function is lower at the beginning of fatigue process, and then consistently gets higher. It concludes that low-fatigue material degradation can be monitored by using ultrasonic method.

  4. The reliability of ultrasonic inspection and the critical defect size

    International Nuclear Information System (INIS)

    Vasilchenko, G.S.; Bely, V.E.; Ovchinnikov, A.V.; Rivkin, E.Yu.

    1991-01-01

    The ability to detect fabrication and service-induced defects in the welded joints of components and pipelines in nuclear power stations by ultrasonic inspection when this is conducted by using standard instruments and procedures appears to be insufficient. This fact was confirmed by the research carried out in PISC program and other studies. In order to increase the accuracy of measurement and to obtain the additional information on the character of any defect in ultrasonic testing as well as the validity of applying nondestructive testing data to strength calculation, scientific researches have been promoted and carried out in the USSR in a program under the guidance of NPO CNIITMASH. The reliability of the ultrasonic control of welded joints and the ways and means for its improvement are discussed. The presentation of the parameters realized by the ultrasonic inspection of defects in the form of schema for the use in strength calculation is explained. The calculation of stress intensity factor, the estimation of critical defect size, and the estimation of acceptable defect size are reported. (K.I.)

  5. Ultrasonic fingerprint sensor using a piezoelectric micromachined ultrasonic transducer array integrated with complementary metal oxide semiconductor electronics

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Y.; Fung, S.; Wang, Q.; Horsley, D. A. [Berkeley Sensor and Actuator Center, University of California, Davis, 1 Shields Avenue, Davis, California 95616 (United States); Tang, H.; Boser, B. E. [Berkeley Sensor and Actuator Center, University of California, Berkeley, California 94720 (United States); Tsai, J. M.; Daneman, M. [InvenSense, Inc., 1745 Technology Drive, San Jose, California 95110 (United States)

    2015-06-29

    This paper presents an ultrasonic fingerprint sensor based on a 24 × 8 array of 22 MHz piezoelectric micromachined ultrasonic transducers (PMUTs) with 100 μm pitch, fully integrated with 180 nm complementary metal oxide semiconductor (CMOS) circuitry through eutectic wafer bonding. Each PMUT is directly bonded to a dedicated CMOS receive amplifier, minimizing electrical parasitics and eliminating the need for through-silicon vias. The array frequency response and vibration mode-shape were characterized using laser Doppler vibrometry and verified via finite element method simulation. The array's acoustic output was measured using a hydrophone to be ∼14 kPa with a 28 V input, in reasonable agreement with predication from analytical calculation. Pulse-echo imaging of a 1D steel grating is demonstrated using electronic scanning of a 20 × 8 sub-array, resulting in 300 mV maximum received amplitude and 5:1 contrast ratio. Because the small size of this array limits the maximum image size, mechanical scanning was used to image a 2D polydimethylsiloxane fingerprint phantom (10 mm × 8 mm) at a 1.2 mm distance from the array.

  6. Towards an Ultrasonic Guided Wave Procedure for Health Monitoring of Composite Vessels: Application to Hydrogen-Powered Aircraft.

    Science.gov (United States)

    Yaacoubi, Slah; McKeon, Peter; Ke, Weina; Declercq, Nico F; Dahmene, Fethi

    2017-09-19

    This paper presents an overview and description of the approach to be used to investigate the behavior and the defect sensitivity of various ultrasonic guided wave (UGW) modes propagating specifically in composite cylindrical vessels in the framework of the safety of hydrogen energy transportation such as hydrogen-powered aircrafts. These structures which consist of thick and multi-layer composites are envisioned for housing hydrogen gas at high pressures. Due to safety concerns associated with a weakened structure, structural health monitoring techniques are needed. A procedure for optimizing damage detection in these structural types is presented. It is shown that a finite element method can help identify useful experimental parameters including frequency range, excitation type, and receiver placement.

  7. A look-up-table digital predistortion technique for high-voltage power amplifiers in ultrasonic applications.

    Science.gov (United States)

    Gao, Zheng; Gui, Ping

    2012-07-01

    In this paper, we present a digital predistortion technique to improve the linearity and power efficiency of a high-voltage class-AB power amplifier (PA) for ultrasound transmitters. The system is composed of a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), and a field-programmable gate array (FPGA) in which the digital predistortion (DPD) algorithm is implemented. The DPD algorithm updates the error, which is the difference between the ideal signal and the attenuated distorted output signal, in the look-up table (LUT) memory during each cycle of a sinusoidal signal using the least-mean-square (LMS) algorithm. On the next signal cycle, the error data are used to equalize the signal with negative harmonic components to cancel the amplifier's nonlinear response. The algorithm also includes a linear interpolation method applied to the windowed sinusoidal signals for the B-mode and Doppler modes. The measurement test bench uses an arbitrary function generator as the DAC to generate the input signal, an oscilloscope as the ADC to capture the output waveform, and software to implement the DPD algorithm. The measurement results show that the proposed system is able to reduce the second-order harmonic distortion (HD2) by 20 dB and the third-order harmonic distortion (HD3) by 14.5 dB, while at the same time improving the power efficiency by 18%.

  8. Measurement of a 3D Ultrasonic Wavefield Using Pulsed Laser Holographic Microscopy for Ultrasonic Nondestructive Evaluation

    Directory of Open Access Journals (Sweden)

    Xing Wang

    2018-02-01

    Full Text Available In ultrasonic array imaging, 3D ultrasonic wavefields are normally recorded by an ultrasonic piezo array transducer. Its performance is limited by the configuration and size of the array transducer. In this paper, a method based on digital holographic interferometry is proposed to record the 3D ultrasonic wavefields instead of the array transducer, and the measurement system consisting of a pulsed laser, ultrasonic excitation, and synchronization and control circuit is designed. A consecutive sequence of holograms of ultrasonic wavefields are recorded by the system. The interferograms are calculated from the recorded holograms at different time sequence. The amplitudes and phases of the transient ultrasonic wavefields are recovered from the interferograms by phase unwrapping. The consecutive sequence of transient ultrasonic wavefields are stacked together to generate 3D ultrasonic wavefields. Simulation and experiments are carried out to verify the proposed technique, and preliminary results are presented.

  9. Laser-Ultrasonic Testing and its Applications to Nuclear Reactor Internals

    Science.gov (United States)

    Ochiai, M.; Miura, T.; Yamamoto, S.

    2008-02-01

    A new nondestructive testing technique for surface-breaking microcracks in nuclear reactor components based on laser-ultrasonics is developed. Surface acoustic wave generated by Q-switched Nd:YAG laser and detected by frequency-stabilized long pulse laser coupled with confocal Fabry-Perot interferometer is used to detect and size the cracks. A frequency-domain signal processing is developed to realize accurate sizing capability. The laser-ultrasonic testing allows the detection of surface-breaking microcrack having a depth of less than 0.1 mm, and the measurement of their depth with an accuracy of 0.2 mm when the depth exceeds 0.5 mm including stress corrosion cracking. The laser-ultrasonic testing system combined with laser peening system, which is another laser-based maintenance technology to improve surface stress, for inner surface of small diameter tube is developed. The generation laser in the laser-ultrasonic testing system can be identical to the laser source of the laser peening. As an example operation of the system, the system firstly works as the laser-ultrasonic testing mode and tests the inner surface of the tube. If no cracks are detected, the system then changes its work mode to the laser peening and improves surface stress to prevent crack initiation. The first nuclear industrial application of the laser-ultrasonic testing system combined with the laser peening was completed in Japanese nuclear power plant in December 2004.

  10. A 25 W 70% Efficiency Doherty Power Amplifier at 6 dB Output Back-Off for 2.4 GHz Applications with VGS, PEAK

    Directory of Open Access Journals (Sweden)

    Jorge Moreno Rubio

    2015-01-01

    Full Text Available This paper shows the design and simulation results of a hybrid Doherty power amplifier. The amplifier has been designed at 2,4 GHz, obtaining power-added efficiency above 70 % for 6 dB output power back-off, together with a small signal gain of 17 dB. Design and analysis equations are presented considering class AB bias conditions for the main amplifier and class C for the peak one in back-off larger than 6 dB, and FET device assumption. An additional control on the bias point of the peak device has been carried out, in order to increase the gain on the Doherty region and ease the design of the peak branch. A Cree’s GaN-HEMT CGH40010F device has been used with a nonlinear model guarantied up to 6 GHz and with an expected output power of 10 W. The obtained output power is higher than 25-W. The simulation has been carried out using Agilent ADS CAD tools. The present design could present the state of the art in terms of continuous-wave (CW characterization

  11. A detector for monitoring the onset of cavitation during therapy-level measurements of ultrasonic power

    Energy Technology Data Exchange (ETDEWEB)

    Hodnett, M; Zeqiri, B [National Physical Laboratory, Queens Road, Teddington, Middlesex, TW11 0LW (United Kingdom)

    2004-01-01

    Acoustic cavitation occurring in the water path between a transducer and the target of a radiation force balance can provide a significant source of error during measurements of ultrasonic power. These problems can be particularly acute at physiotherapy levels (>1 W), and low frequencies ({<=} 1 MHz). The cavitating bubbles can absorb and scatter incident ultrasound, leading to an underestimate in the measured power. For these reasons, International Specification standards demand the use of degassed water. This imposes requirements that may actually be difficult to meet, for example, in the case of hospitals. Also, initially degassed water will rapidly re-gas, increasing the likelihood of cavitation occurring. For these reasons, NPL has developed a device that monitors acoustic emissions generated by bubble activity, for detecting the onset of cavitation during power measurements. A commercially available needle hydrophone is used to detect these emissions. The acoustic signals are then monitored using a Cavitation Detector (CD) unit, comprising an analogue electrical filter that may be tuned to detect frequency components generated by cavitating bubbles, and which provides an indication of when the measured level exceeds a pre-defined threshold. This paper describes studies to establish a suitable detection scheme, the principles of operation of the CD unit, and the performance tests carried out with a range of propagation media.

  12. A detector for monitoring the onset of cavitation during therapy-level measurements of ultrasonic power

    International Nuclear Information System (INIS)

    Hodnett, M; Zeqiri, B

    2004-01-01

    Acoustic cavitation occurring in the water path between a transducer and the target of a radiation force balance can provide a significant source of error during measurements of ultrasonic power. These problems can be particularly acute at physiotherapy levels (>1 W), and low frequencies (≤ 1 MHz). The cavitating bubbles can absorb and scatter incident ultrasound, leading to an underestimate in the measured power. For these reasons, International Specification standards demand the use of degassed water. This imposes requirements that may actually be difficult to meet, for example, in the case of hospitals. Also, initially degassed water will rapidly re-gas, increasing the likelihood of cavitation occurring. For these reasons, NPL has developed a device that monitors acoustic emissions generated by bubble activity, for detecting the onset of cavitation during power measurements. A commercially available needle hydrophone is used to detect these emissions. The acoustic signals are then monitored using a Cavitation Detector (CD) unit, comprising an analogue electrical filter that may be tuned to detect frequency components generated by cavitating bubbles, and which provides an indication of when the measured level exceeds a pre-defined threshold. This paper describes studies to establish a suitable detection scheme, the principles of operation of the CD unit, and the performance tests carried out with a range of propagation media

  13. Ultrasonic Transducer Design for the Axial Flaw Detection of Dissimilar Metal Weld

    International Nuclear Information System (INIS)

    Yoon, Byung Sik; Kim, Yong Sik; Yang, Seung Han

    2011-01-01

    Dissimilar metal welds in nuclear power plant are known as very susceptible to PWSCC flaws, and periodically inspected by the qualified inspector and qualified procedure during in-service inspection period. According to field survey data, the majority of their DMWs are located on tapered nozzle or adjacent to a tapered component. These types of configurations restrict examination access and also limit examination volume coverage. Additionally, circumferential scan for axially oriented flaw is very difficult to detect located on tapered surface because the transducer can't receive flaw response from reflector for miss-orientation. To overcome this miss-orientation, it is necessary adapt skewed ultrasonic transducer accommodate tapered surface. The skewed refracted longitudinal ultrasonic transducer designed by modeling and manufactured from the modelling result for axial flaw detection. Experimental results showed that the skewed refracted longitudinal ultrasonic transducer get higher flaw response than non-skewed refracted longitudinal ultrasonic transducer

  14. Market power and output-based refunding of environmental policy revenues

    International Nuclear Information System (INIS)

    Fischer, Carolyn

    2011-01-01

    Output-based refunding of environmental policy revenues combines a tax on emissions with a production subsidy, typically in a revenue-neutral fashion. With imperfect competition, subsidies can alleviate output underprovision. However, when market shares are significant, endogenous refunding reduces abatement incentives and the marginal net tax or subsidy. If market shares differ, marginal abatement costs will not be equalized, and production is shifted among participants. In an asymmetric Cournot duopoly, endogenous refunding leads to higher output, emissions, and overall costs compared with a fixed rebate program targeting the same emissions intensity. These results hold whether emissions rates are determined simultaneously with output or strategically in a two-stage model. (author)

  15. Electrical output of bryophyte microbial fuel cell systems is sufficient to power a radio or an environmental sensor.

    Science.gov (United States)

    Bombelli, Paolo; Dennis, Ross J; Felder, Fabienne; Cooper, Matt B; Madras Rajaraman Iyer, Durgaprasad; Royles, Jessica; Harrison, Susan T L; Smith, Alison G; Harrison, C Jill; Howe, Christopher J

    2016-10-01

    Plant microbial fuel cells are a recently developed technology that exploits photosynthesis in vascular plants by harnessing solar energy and generating electrical power. In this study, the model moss species Physcomitrella patens , and other environmental samples of mosses, have been used to develop a non-vascular bryophyte microbial fuel cell (bryoMFC). A novel three-dimensional anodic matrix was successfully created and characterized and was further tested in a bryoMFC to determine the capacity of mosses to generate electrical power. The importance of anodophilic microorganisms in the bryoMFC was also determined. It was found that the non-sterile bryoMFCs operated with P. patens delivered over an order of magnitude higher peak power output (2.6 ± 0.6 µW m -2 ) than bryoMFCs kept in near-sterile conditions (0.2 ± 0.1 µW m -2 ). These results confirm the importance of the microbial populations for delivering electrons to the anode in a bryoMFC. When the bryoMFCs were operated with environmental samples of moss (non-sterile) the peak power output reached 6.7 ± 0.6 mW m -2 . The bryoMFCs operated with environmental samples of moss were able to power a commercial radio receiver or an environmental sensor (LCD desktop weather station).

  16. The Effect of Electrical Impedance Matching on the Electromechanical Characteristics of Sandwiched Piezoelectric Ultrasonic Transducers

    Directory of Open Access Journals (Sweden)

    Yuan Yang

    2017-12-01

    Full Text Available For achieving the power maximum transmission, the electrical impedance matching (EIM for piezoelectric ultrasonic transducers is highly required. In this paper, the effect of EIM networks on the electromechanical characteristics of sandwiched piezoelectric ultrasonic transducers is investigated in time and frequency domains, based on the PSpice model of single sandwiched piezoelectric ultrasonic transducer. The above-mentioned EIM networks include, series capacitance and parallel inductance (I type and series inductance and parallel capacitance (II type. It is shown that when I and II type EIM networks are used, the resonance and anti-resonance frequencies and the received signal tailing are decreased; II type makes the electro-acoustic power ratio and the signal tailing smaller whereas it makes the electro-acoustic gain ratio larger at resonance frequency. In addition, I type makes the effective electromechanical coupling coefficient increase and II type makes it decrease; II type make the power spectral density at resonance frequency more dramatically increased. Specially, the electro-acoustic power ratio has maximum value near anti-resonance frequency, while the electro-acoustic gain ratio has maximum value near resonance frequency. It can be found that the theoretically analyzed results have good consistency with the measured ones.

  17. Ultrasonic unit for line-by-line ultrasonic scanning of bodies

    International Nuclear Information System (INIS)

    Soldner, R.

    1978-01-01

    The ultrasonic unit for medical diagnostics operates by the sectorial scanning principle, which avoids direct coupling of the transducer head to the surface of the body. For this purpose, several transmitter/receiver units (approx. 100) are arranged on a partial ring of a circular arc and the ultrasonic beams, which can be triggered sequentially in time, are directed at a common intersection behind the ultrasonic window of the unit, i.e., outside the unit. A mechanical system is employed to set and adjust the partial ring carrying the transmitter/receiver units. (DG) [de

  18. CFD Study on Aerodynamic Power Output Changes with Inter-Turbine Spacing Variation for a 6 MW Offshore Wind Farm

    Directory of Open Access Journals (Sweden)

    Nak Joon Choi

    2014-11-01

    Full Text Available This study examined the aerodynamic power output change of wind turbines with inter-turbine spacing variation for a 6 MW wind farm composed of three sets of 2 MW wind turbines using computational fluid dynamics (CFD. The wind farm layout design is becoming increasingly important as the use of wind energy is steadily increasing. Among the many wind farm layout design parameters, the inter-turbine spacing is a key factor in the initial investment cost, annual energy production and maintenance cost. The inter-turbine spacing should be determined to maximize the annual energy production and minimize the wake effect, turbulence effect and fatigue load during the service lifetime of wind turbines. Therefore, some compromise between the aerodynamic power output of wind turbines and the inter-turbine spacing is needed. An actuator disc model with the addition of a momentum source was not used, and instead, a full 3-dimensional model with a tower and nacelle was used for CFD analysis because of its great technical significance. The CFD analysis results, such as the aerodynamic power output, axial direction wind speed change, pressure drop across the rotor of wind turbine, and wind speed deficit due to the wake effect with inter-turbine spacing variation, were studied. The results of this study can be applied effectively to wind farm layout design and evaluation.

  19. Optimization of ultrasonic-assisted extraction of pomegranate (Punica granatum L.) seed oil.

    Science.gov (United States)

    Tian, Yuting; Xu, Zhenbo; Zheng, Baodong; Martin Lo, Y

    2013-01-01

    The effectiveness of ultrasonic-assisted extraction (UAE) of pomegranate seed oil (PSO) was evaluated using a variety of solvents. Petroleum ether was the most effective for oil extraction, followed by n-hexane, ethyl acetate, diethyl ether, acetone, and isopropanol. Several variables, such as ultrasonic power, extraction temperature, extraction time, and the ratio of solvent volume and seed weight (S/S ratio) were studied for optimization using response surface methodology (RSM). The highest oil yield, 25.11% (w/w), was obtained using petroleum ether under optimal conditions for ultrasonic power, extraction temperature, extraction time, and S/S ratio at 140 W, 40 °C, 36 min, and 10 ml/g, respectively. The PSO yield extracted by UAE was significantly higher than by using Soxhlet extraction (SE; 20.50%) and supercriti cal fluid extraction (SFE; 15.72%). The fatty acid compositions were significantly different among the PSO extracted by Soxhlet extraction, SFE, and UAE, with punicic acid (>65%) being the most dominant using UAE. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Ultrasonication and food technology: A review

    OpenAIRE

    Ishrat Majid; Gulzar Ahmad Nayik; Vikas Nanda

    2015-01-01

    With increasing consumers demand and tightening of food and environmental regulations, traditional food-processing techniques have lost their optimum performance which gave rise to new and powerful technologies. Ultrasonic is a one of the fast, versatile, emerging, and promising non-destructive green technology used in the food industry from last few years. The ultrasound is being carried out in various areas of food technology namely crystallization, freezing, bleaching, degassing, extractio...

  1. Preparation and characterization of CNTs/UHMWPE nanocomposites via a novel mixer under synergy of ultrasonic wave and extensional deformation.

    Science.gov (United States)

    Yin, Xiaochun; Li, Sai; He, Guangjian; Feng, Yanhong; Wen, Jingsong

    2018-05-01

    In this work, design and development of a new melt mixing method and corresponding mixer for polymer materials were reported. Effects of ultrasonic power and sonication time on the carbon nanotubes (CNTs) filled ultra high molecular weight polyethylene (UHMWPE) nanocomposites were experimentally studied. Transmission Electron Microscopy images showed that homogeneous dispersion of CNTs in intractable UHMWPE matrix is successfully realized due to the synergetic effect of ultrasonic wave and extensional deformation without any aid of other additives or solvents. Differential scanning calorimetry results revealed an increase in crystallinity and crystallization rate due to the finer dispersion of the CNTs in the matrix which act as nucleating point. Composites' complex viscosity and storage modulus decreased sharply at first and then leveled off with the increase of sonication time or the ultrasonic power. The thermal stability and the tensile strength of the CNTs/UHMWPE nanocomposites improved by using this novel mixing method. This is the first method that combined the ultrasonic wave and the extensional deformation in which the elongation rate, sonication time and ultrasonic power can be adjusted simultaneously during mixing. The novel mixer offers several advantages such as environment-friendly, high mixing efficiency, self-cleaning and wide adaptability to materials. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Ultrasonic boiler inspection and economic analysis guidelines

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Boiler tube failures cause approximately 6% availability loss of large fossil-fired power generating plants. This loss can be reduced by systematic approaches using ultrasonic examination and root cause failure analysis methods. Two projects sponsored by EPRI have provided utility engineers with guidelines for performing ultrasonic examinations and with details on 22 types of tube failure mechanisms. A manual has been published that provides descriptions of typical locations, superficial appearances, damage mechanisms, metallurgy, microstructural changes, likely root causes, and potential corrective actions. Application of the principles in the manual is being demonstrated in an EPRI-funded project at 10 electric utilities over the next two years. Guidelines have been published that prescribe the activities necessary for ultrasonic examinations of boiler tubes. Eight essential elements of a boiler examination should be performed to assure that possible economic benefits are obtained. Work was supported by EPRI under RP 1890 and RP 1865. A software package has been developed for effectively planning inspections for wall thinning in fossil-fired boiler tubing. The software assists in minimizing costs associated with maintenance, such as inspection and repair, while the life of the boiler is maximized

  3. Thickness measurement by using cepstrum ultrasonic signal processing

    International Nuclear Information System (INIS)

    Choi, Young Chul; Yoon, Chan Hoon; Choi, Heui Joo; Park, Jong Sun

    2014-01-01

    Ultrasonic thickness measurement is a non-destructive method to measure the local thickness of a solid element, based on the time taken for an ultrasound wave to return to the surface. When an element is very thin, it is difficult to measure thickness with the conventional ultrasonic thickness method. This is because the method measures the time delay by using the peak of a pulse, and the pulses overlap. To solve this problem, we propose a method for measuring thickness by using the power cepstrum and the minimum variance cepstrum. Because the cepstrums processing can divides the ultrasound into an impulse train and transfer function, where the period of the impulse train is the traversal time, the thickness can be measured exactly. To verify the proposed method, we performed experiments with steel and, acrylic plates of variable thickness. The conventional method is not able to estimate the thickness, because of the overlapping pulses. However, the cepstrum ultrasonic signal processing that divides a pulse into an impulse and a transfer function can measure the thickness exactly.

  4. SNR in ultrasonic pluse compression using Golay codes

    International Nuclear Information System (INIS)

    Kim, Young Hwan; Kim, Young Gil; Jeong, Peter

    1994-01-01

    The conventional ultrasonic flaw detection system uses a large amplitude narrow pulse to excite a transducer, however, these systems are limited in average transmit power. An excessively large amplitude causes a dielectric breakage of the transducer, and an excessively long pulse cuases decrease of the resolution. Using the pulse compression, a long pulse of psudorandom signal can be used without sacrificing resolution by signal correlation. In the present work, the pulse compression technique was utilized to the ultrasonic system. Golay code was used as a psudorandom signal in this system, since pair sum of auto-correlations has not sidelobe. The equivalent input pulse of the Golay code was proposed to analyze the pulse compression system. In experiment, the material type, material thickness and code length were considered. As results, pulse compression system considerably reduced system's white noise, and approximately 30 dB improvement in SNR was obtained over the conventional ultrasonic system. The technique seems to perform particularly well with highly energy-absorbent materials such as polymers, plastics and rubbers.

  5. Generation and detection technique of laser-ultrasonic

    International Nuclear Information System (INIS)

    Dho, Sang Whoe; Lee, Seung Seok

    1999-01-01

    A number of physical processes may take place when a solid surface is illuminated by a pulse laser. At lower power region these include heating, the generation of thermal waves, elastic waves (ultrasound). At higher powers, material may be ablated from the surface and a plasma formed, while in the sample there may be melting, plastic deformation and even the formation of cracks. In this letter we consider the generation techniques of laser-ultrasonic il all possible state. And we consider the measurement technique of laser-generated ultrasound based on the optical method.

  6. Reproduction of mouse-pup ultrasonic vocalizations by nanocrystalline silicon thermoacoustic emitter

    Science.gov (United States)

    Kihara, Takashi; Harada, Toshihiro; Kato, Masahiro; Nakano, Kiyoshi; Murakami, Osamu; Kikusui, Takefumi; Koshida, Nobuyoshi

    2006-01-01

    As one of the functional properties of ultrasound generator based on efficient thermal transfer at the nanocrystalline silicon (nc-Si) layer surface, its potential as an ultrasonic simulator of vocalization signals is demonstrated by using the acoustic data of mouse-pup calls. The device composed of a surface-heating thin-film electrode, an nc-Si layer, and a single-crystalline silicon (c-Si) wafer, exhibits an almost completely flat frequency response over a wide range without any mechanical surface vibration systems. It is shown that the fabricated emitter can reproduce digitally recorded ultrasonic mouse-pups vocalizations very accurately in terms of the call duration, frequency dispersion, and sound pressure level. The thermoacoustic nc-Si device provides a powerful physical means for the understanding of ultrasonic communication mechanisms in various living animals.

  7. Phased array ultrasonic testing of dissimilar metal pipe weld joints

    International Nuclear Information System (INIS)

    Rajeev, J.; Sankaranarayanan, R.; Sharma, Govind K; Joseph, A.; Purnachandra Rao, B.

    2015-01-01

    Dissimilar metal weld (DMW) joints made of stainless steel and ferritic steel is used in nuclear industries as well as oil and gas industries. These joints are prone to frequent failures which makes the non-destructive testing of dissimilar metal weld joints utmost important for reliable and safe operation of nuclear power plants and oil and gas industries. Ultrasonic inspection of dissimilar metal weld joints is still challenging due to the inherent anisotropic and highly scattering nature. Phased array ultrasonic testing (PAUT) is an advanced technique and its capability has not been fully explored for the inspection of dissimilar metal welds

  8. A comprehensive analysis and hardware implementation of control strategies for high output voltage DC-DC boost power converter

    OpenAIRE

    Padmanaban, Sanjeevikumar; Grandi, Gabriele; Blaabjerg, Frede; Wheeler, Patrick; Siano, Pierluigi; Hammami, Manel

    2017-01-01

    Classical DC-DC converters used in high voltage direct current (HVDC) power transmission systems, lack in terms of efficiency, reduced transfer gain and increased cost with sensor (voltage/current) numbers. Besides, the internal self-parasitic behavior of the power components reduces the output voltage and efficiency of classical HV converters. This paper deals with extra high-voltage (EHV) dc-dc boost converter by the application of voltage-lift technique to overcome the aforementioned defic...

  9. Design and analysis of optimised class E power amplifier using shunt capacitance in the output structure

    Science.gov (United States)

    Hayati, Mohsen; Roshani, Sobhan; Zirak, Ali Reza

    2017-05-01

    In this paper, a class E power amplifier (PA) with operating frequency of 1 MHz is presented. MOSFET non-linear drain-to-source parasitic capacitance, linear external capacitance at drain-to-source port and linear shunt capacitance in the output structure are considered in design theory. One degree of freedom is added to the design of class E PA, by assuming the shunt capacitance in the output structure in the analysis. With this added design degree of freedom it is possible to achieve desired values for several parameters, such as output voltage, load resistance and operating frequency, while both zero voltage and zero derivative switching (ZVS and ZDS) conditions are satisfied. In the conventional class E PA, high value of peak switch voltage results in limitations for the design of amplifier, while in the presented structure desired specifications could be achieved with the safe margin of peak switch voltage. The results show that higher operating frequency and output voltage can also be achieved, compared to the conventional structure. PSpice software is used in order to simulate the designed circuit. The presented class E PA is designed, fabricated and measured. The measured results are in good agreement with simulation and theory results.

  10. Role of ultrasonic irradiation on transesterification of palm oil using calcium oxide as a solid base catalyst

    International Nuclear Information System (INIS)

    Poosumas, Jutipong; Ngaosuwan, Kanokwan; Quitain, Armando T.; Assabumrungrat, Suttichai

    2016-01-01

    Highlights: • Transesterification of palm oil using a circulated continuous flow ultrasonic reactor. • Heterogeneous system using CaO as catalyst. • Effects of ultrasonic frequency and power, and catalyst reusability were considered. • A single high frequency and high intensity irradiation is favorable for heterogeneous system. - Abstract: Biodiesel production from transesterification of palm oil using a circulated continuous flow ultrasonic reactor was investigated. Transesterification was carried out at 60 °C, 1 atm and a methanol-to-oil molar ratio of 9:1. The highest reaction rate was achieved at the catalyst loading of 2 wt%, and biodiesel yield constantly increased until transesterification equilibrium (about 80%) was reached. A higher ultrasonic frequency (50 kHz) promoted the heterogeneously catalyzed transesterification of refined palm oil, because the three-phase system (packed solid catalyst, methanol and oil) required more spatial distribution by ultrasonic irradiation. Moreover, the highest ultrasonic power also provided highest transesterification rate and biodiesel yield due to cavitation activity enhancement. Reusability of calcium oxide catalysts was also investigated, and results showed that this can be reused to provide high biodiesel yield for at least three operations with slight decrease in the rate of reaction due to counter balance effect of organic compounds deposition on the catalyst surface. The results from this study can be a basis for scaling up of the process to industrial scale.

  11. Mechanisation of ultrasonic testing in nuclear power plants

    International Nuclear Information System (INIS)

    Seifert, W.

    1979-01-01

    Mechanical ultrasonic testing devices should meet the following requirements: Remote-controlled or automatic guidance of the US test systems at the test site according to given test parameters; exact positioning of the test system at the test site; high start-up accuracy and reproducibility; access to test regions that are hardly accessible or inaccessible for manual inspection; reduction of the radiation exposure of the operating personnel, and short assembling and testing time. The manipulators developed according to these requirements permit meandering test courses of the US test system on the pressure vessel surface or circular or semicircular courses around the nozzles or pipes in order to test welds and pipe joints. Every movement of the test system is taken up by a transmitting apparatus. (orig./HP) [de

  12. Compact and air-transportable ultrasonic turbine disc bore inspection system

    International Nuclear Information System (INIS)

    Larsen, R.E.; Leon-Salamanca, T.

    1990-01-01

    A compact, lightweight, air-transportable ultrasonic inspection system for bore and keyway regions of shrunk-on turbine discs has been developed. The system utilizes a proprietary ultrasound liquid coupling technique in conjunction with a single pair of gimballed search units to achieve rapid and thorough coverage of bores and keyways in both heavy nuclear and standard fossil discs of nearly any size and having any conceivable web surface contour. Search unit positioning and angulation parameter settings are established in near real-time through a computation algorithm based on a compact vector ray tracing protocol. Modular construction and the use of lightweight, stiff materials throughout facilitates air shipment of the system and its rapid deployment at continental and overseas field sites. Mechanical and ultrasonic features of the system are described. Development and application of the computation algorithm to the ultrasonic inspection of heavy discs at an overseas power station is discussed

  13. Towards an Ultrasonic Guided Wave Procedure for Health Monitoring of Composite Vessels: Application to Hydrogen-Powered Aircraft

    Directory of Open Access Journals (Sweden)

    Slah Yaacoubi

    2017-09-01

    Full Text Available This paper presents an overview and description of the approach to be used to investigate the behavior and the defect sensitivity of various ultrasonic guided wave (UGW modes propagating specifically in composite cylindrical vessels in the framework of the safety of hydrogen energy transportation such as hydrogen-powered aircrafts. These structures which consist of thick and multi-layer composites are envisioned for housing hydrogen gas at high pressures. Due to safety concerns associated with a weakened structure, structural health monitoring techniques are needed. A procedure for optimizing damage detection in these structural types is presented. It is shown that a finite element method can help identify useful experimental parameters including frequency range, excitation type, and receiver placement.

  14. Zinc oxide integrated area efficient high output low power wavy channel thin film transistor

    International Nuclear Information System (INIS)

    Hanna, A. N.; Ghoneim, M. T.; Bahabry, R. R.; Hussain, A. M.; Hussain, M. M.

    2013-01-01

    We report an atomic layer deposition based zinc oxide channel material integrated thin film transistor using wavy channel architecture allowing expansion of the transistor width in the vertical direction using the fin type features. The experimental devices show area efficiency, higher normalized output current, and relatively lower power consumption compared to the planar architecture. This performance gain is attributed to the increased device width and an enhanced applied electric field due to the architecture when compared to a back gated planar device with the same process conditions

  15. Calculation of the optimum fuel distribution which maximizes the power output of a reactor

    International Nuclear Information System (INIS)

    Santos, W.N. dos.

    1979-01-01

    Using optimal control techniques, the optimum fuel distribution - which maximizes the power output of a thermal reactor - is obtained. The nuclear reactor is described by a diffusion theory model with four energy groups and by assuming plane geometry. Since the analytical solution is impracticable, by using a perturbation method, a FORTRAN program was written, in order to obtain the numerical solution. Numerical results, for a thermal reactor light water moderated, non reflected, are shown. The fissile fuel material considered is Uranium-235. (Author) [pt

  16. Zinc oxide integrated area efficient high output low power wavy channel thin film transistor

    KAUST Repository

    Hanna, Amir; Ghoneim, Mohamed T.; Bahabry, Rabab R.; Hussain, Aftab M.; Hussain, Muhammad Mustafa

    2013-01-01

    We report an atomic layer deposition based zinc oxide channel material integrated thin film transistor using wavy channel architecture allowing expansion of the transistor width in the vertical direction using the fin type features. The experimental devices show area efficiency, higher normalized output current, and relatively lower power consumption compared to the planar architecture. This performance gain is attributed to the increased device width and an enhanced applied electric field due to the architecture when compared to a back gated planar device with the same process conditions.

  17. Zinc oxide integrated area efficient high output low power wavy channel thin film transistor

    KAUST Repository

    Hanna, Amir

    2013-11-26

    We report an atomic layer deposition based zinc oxide channel material integrated thin film transistor using wavy channel architecture allowing expansion of the transistor width in the vertical direction using the fin type features. The experimental devices show area efficiency, higher normalized output current, and relatively lower power consumption compared to the planar architecture. This performance gain is attributed to the increased device width and an enhanced applied electric field due to the architecture when compared to a back gated planar device with the same process conditions.

  18. Design and Manufacture an Ultrasonic Dispersion System with Automatic Frequency Adjusting Property

    Directory of Open Access Journals (Sweden)

    Herlina ABDUL RAHIM

    2011-03-01

    Full Text Available This paper a novel ultrasonic dispersion system for the cleaning application or dispersing of particles which are mixed in liquid has been proposed. The frequency band of designed system is 30 kHz so that the frequency of ultrasonic wave sweeps from 30 kHz to 60 kHz with 100 Hz steps. One of the superiority of manufactured system in compare with the other similar systems which are available in markets is that this system can transfer the maximum and optimum energy of ultrasonic wave inside the liquid tank with the high efficiency in the whole of the usage time of the system. The used ultrasonic transducers in this system as the generator of ultrasonic wave is the type of air coupled ceramic ultrasonic piezoelectric with the nominal maximum power 50 Watt. The frequency characteristic of applied piezoelectric is that it produces the maximum amplitude of ultrasonic wave on the resonance frequency, so this system is designed to work on resonance frequency of piezoelectric, continuously. This is done by the use of control system which is consisted of two major parts, sensing part and controlling part. The manufactured ultrasonic dispersion system is consisted of 9 piezoelectrics so that it can produce 450 watt ultrasonic energy, totally. The main purpose of this project is to produce a safety system especially for fatigue car driver so as to prevent from accidents. The statistic on road fatality shows that human error constitute of 64.84 % road accidents fatality and 17.4 % due to technical factors. These systems encompassed the approach of hand pressure applied on the steering wheel. The steering will be installed with pressure sensors. At the same time these sensors can be used to measure gripping force while driving.

  19. Countermovement depth - a variable which clarifies the relationship between the maximum power output and height of a vertical jump.

    Science.gov (United States)

    Gajewski, Jan; Michalski, Radosław; Buśko, Krzysztof; Mazur-Różycka, Joanna; Staniak, Zbigniew

    2018-01-01

    The aim of this study was to identify the determinants of peak power achieved during vertical jumps in order to clarify relationship between the height of jump and the ability to exert maximum power. One hundred young (16.8±1.8 years) sportsmen participated in the study (body height 1.861 ± 0.109 m, body weight 80.3 ± 9.2 kg). Each participant performed three jump tests: countermovement jump (CMJ), akimbo countermovement jump (ACMJ), and spike jump (SPJ). A force plate was used to measure ground reaction force and to determine peak power output. The following explanatory variables were included in the model: jump height, body mass, and the lowering of the centre of mass before launch (countermovement depth). A model was created using multiple regression analysis and allometric scaling. The model was used to calculate the expected power value for each participant, which correlated strongly with real values. The value of the coefficient of determination R2 equalled 0.89, 0.90 and 0.98, respectively, for the CMJ, ACMJ, and SPJ jumps. The countermovement depth proved to be a variable strongly affecting the maximum power of jump. If the countermovement depth remains constant, the relative peak power is a simple function of jump height. The results suggest that the jump height of an individual is an exact indicator of their ability to produce maximum power. The presented model has a potential to be utilized under field condition for estimating the maximum power output of vertical jumps.

  20. Self-mode-locking operation of a diode-end-pumped Tm:YAP laser with watt-level output power

    Science.gov (United States)

    Zhang, Su; Zhang, Xinlu; Huang, Jinjer; Wang, Tianhan; Dai, Junfeng; Dong, Guangzong

    2018-03-01

    We report on a high power continuous wave (CW) self-mode-locked Tm:YAP laser pumped by a 792 nm laser diode. Without any additional mode-locking elements in the cavity, stable and self-starting mode-locking operation has been realized. The threshold pump power of the CW self-mode-locked Tm:YAP laser is only 5.4 W. The maximum average output power is as high as 1.65 W at the pump power of 12 W, with the repetition frequency of 468 MHz and the center wavelength of 1943 nm. To the best of our knowledge, this is the first CW self-mode-locked Tm:YAP laser. The experiment results show that the Tm:YAP crystal is a promising gain medium for realizing the high power self-mode-locking operation at 2 µm.