WorldWideScience

Sample records for advanced ultrasonic methods

  1. Assessment of Crack Detection in Heavy-Walled Cast Stainless Steel Piping Welds Using Advanced Low-Frequency Ultrasonic Methods

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Michael T.; Crawford, Susan L.; Cumblidge, Stephen E.; Denslow, Kayte M.; Diaz, Aaron A.; Doctor, Steven R.

    2007-03-01

    Studies conducted at the Pacific Northwest National Laboratory in Richland, Washington, have focused on assessing the effectiveness and reliability of novel approaches to nondestructive examination (NDE) for inspecting coarse-grained, cast stainless steel reactor components. The primary objective of this work is to provide information to the U.S. Nuclear Regulatory Commission on the effectiveness and reliability of advanced NDE methods as related to the inservice inspection of safety-related components in pressurized water reactors (PWRs). This report provides progress, recent developments, and results from an assessment of low frequency ultrasonic testing (UT) for detection of inside surface-breaking cracks in cast stainless steel reactor piping weldments as applied from the outside surface of the components. Vintage centrifugally cast stainless steel piping segments were examined to assess the capability of low-frequency UT to adequately penetrate challenging microstructures and determine acoustic propagation limitations or conditions that may interfere with reliable flaw detection. In addition, welded specimens containing mechanical and thermal fatigue cracks were examined. The specimens were fabricated using vintage centrifugally cast and statically cast stainless steel materials, which are typical of configurations installed in PWR primary coolant circuits. Ultrasonic studies on the vintage centrifugally cast stainless steel piping segments were conducted with a 400-kHz synthetic aperture focusing technique and phased array technology applied at 500 kHz, 750 kHz, and 1.0 MHz. Flaw detection and characterization on the welded specimens was performed with the phased array method operating at the frequencies stated above. This report documents the methodologies used and provides results from laboratory studies to assess baseline material noise, crack detection, and length-sizing capability for low-frequency UT in cast stainless steel piping.

  2. Pulsed ultrasonic stir welding method

    Science.gov (United States)

    Ding, R. Jeffrey (Inventor)

    2013-01-01

    A method of performing ultrasonic stir welding uses a welding head assembly to include a plate and a rod passing through the plate. The rod is rotatable about a longitudinal axis thereof. In the method, the rod is rotated about its longitudinal axis during a welding operation. During the welding operation, a series of on-off ultrasonic pulses are applied to the rod such that they propagate parallel to the rod's longitudinal axis. At least a pulse rate associated with the on-off ultrasonic pulses is controlled.

  3. Design of advanced ultrasonic transducers for welding devices.

    Science.gov (United States)

    Parrini, L

    2001-11-01

    A new high frequency ultrasonic transducer has been conceived, designed, prototyped, and tested. In the design phase, an advanced approach was used and established. The method is based on an initial design estimate obtained with finite element method (FEM) simulations. The simulated ultrasonic transducers and resonators are then built and characterized experimentally through laser interferometry and electrical resonance spectra. The comparison of simulation results with experimental data allows the parameters of FEM models to be adjusted and optimized. The achieved FEM simulations exhibit a remarkably high predictive potential and allow full control of the vibration behavior of the transducer. The new transducer is mounted on a wire bonder with a flange whose special geometry was calculated by means of FEM simulations. This flange allows the transducer to be attached on the wire bonder, not only in longitudinal nodes, but also in radial nodes of the ultrasonic field excited in the horn. This leads to a total decoupling of the transducer to the wire bonder, which has not been achieved so far. The new approach to mount ultrasonic transducers on a welding device is of major importance, not only for wire bonding, but also for all high power ultrasound applications and has been patented.

  4. Flow measurement by ultrasonic method

    International Nuclear Information System (INIS)

    An Ultrasonic Flow Meter (USFM) wasdeveloped to measure flow velocity of high temperature fluid in a pipe. To protect ultrasonic transducers from high temperature, guide rods were used. From the study on mechanical structure and acoustic property, the guide rod and the electronic circuit were improved to have capabilities of temperature compensation, quick response, high accuracy and not to be easily disturbed by bubbles contained in the fluid flow. Using a water flow loop, the test results proved the accuracy of +-1.0 percent and response time of 10 m sec

  5. Ultrasonic methods in solid state physics

    CERN Document Server

    Truell, John; Elbaum, Charles

    1969-01-01

    Ultrasonic Methods in Solid State Physics is devoted to studies of energy loss and velocity of ultrasonic waves which have a bearing on present-day problems in solid-state physics. The discussion is particularly concerned with the type of investigation that can be carried out in the megacycle range of frequencies from a few megacycles to kilomegacycles; it deals almost entirely with short-duration pulse methods rather than with standing-wave methods. The book opens with a chapter on a classical treatment of wave propagation in solids. This is followed by separate chapters on methods and techni

  6. Advanced ultrasonic testing of complex shaped composite structures

    Science.gov (United States)

    Dolmatov, D.; Zhvyrblya, V.; Filippov, G.; Salchak, Y.; Sedanova, E.

    2016-06-01

    Due to the wide application of composite materials it is necessary to develop unconventional quality control techniques. One of the methods that can be used for this purpose is ultrasonic tomography. In this article an application of a robotic ultrasonic system is considered. Precise positioning of the robotic scanner and path generating are defined as ones of the most important aspects. This study proposes a non-contact calibration method of a robotic ultrasonic system. Path of the scanner requires a 3D model of controlled objects which are created in accordance with the proposed algorithm. The suggested techniques are based on implementation of structured light method.

  7. Characterization methods for ultrasonic test systems

    Energy Technology Data Exchange (ETDEWEB)

    Busse, L.J.; Becker, F.L.; Bowey, R.E.; Doctor, S.R.; Gribble, R.P.; Posakony, G.J.

    1982-07-01

    Methods for the characterization of ultrasonic transducers (search units) and instruments are presented. The instrument system is considered as three separate components consisting of a transducer, a receiver-display, and a pulser. The operation of each component is assessed independently. The methods presented were chosen because they provide the greatest amount of information about component operation and were not chosen based upon such conditions as cost, ease of operation, field implementation, etc. The results of evaluating a number of commercially available ultrasonic test instruments are presented.

  8. A comparison of conventional and advanced ultrasonic inspection techniques in the characterization of TMC materials

    Science.gov (United States)

    Holland, Mark R.; Handley, Scott M.; Miller, James G.; Reighard, Mark K.

    1992-01-01

    Results obtained with a conventional ultrasonic inspection technique as well as those obtained with more advanced ultrasonic NDE methods in the characterization of an 8-ply quasi-isotropic titanium matrix composite (TMC) specimen are presented. Images obtained from a conventional ultrasonic inspection of TMC material are compared with those obtained using more sophisticated ultrasonic inspection methods. It is suggested that the latter techniques are able to provide quantitative images of TMC material. They are able to reveal the same potential defect indications while simultaneously providing more quantitative information concerning the material's inherent properties. Band-limited signal loss and slope-of-attenuation images provide quantitative data on the inherent material characteristics and defects in TMC.

  9. 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

  10. Equipment for flow measurements according to the ultrasonic Doppler method

    International Nuclear Information System (INIS)

    An instrument for flow measurements according to the ultrasonic Doppler method is described. It consists of an applicator with an ultrasonic oscillator and, connected to it, a Doppler instrument for the Doppler flow record. The angle of incidence of the ultrasonic beam may be taken into account, flow measurement independent of the angle thus becoming possible. (RW)

  11. Training methods in non-destructive examination with ultrasonic testing

    International Nuclear Information System (INIS)

    German concept for inspection of LWR, leak before break, basic safety; General inspection methods; Ultrasonic inspection - basic principle, generation of ultrasound, bulk and surface waves, piezo electric and electromagnetic transducers, energy balance, scattering and adsorption, divergence; Ultra techniques in compliance with KTA-rules - pulse-echo, tandem, throughtransmission; Valuation of ultrasonic indications; Pre- and in-service inspection; Practical part - ultrasonic equipment, ultrasonic piezo electric transducers, wall thickness measurement, crack depth measurement with potential drop technique. (orig.)

  12. New technology for the design of advanced ultrasonic transducers for high-power applications.

    Science.gov (United States)

    Parrini, Lorenzo

    2003-06-01

    A new high-frequency ultrasonic transducer for wire bonding has been conceived, designed, prototyped and tested. In the design phase an advanced approach was used and established. The method is based on the two basic principles of modularity and iteration. The transducer is decomposed to its elementary components. For each component an initial design is obtained with finite elements method (FEM) simulations. The simulated ultrasonic modules are then built and characterized experimentally through laser-interferometry measurements and electrical resonance spectra. The comparison of simulation results with experimental data allows the parameters of FEM models to be iteratively adjusted and optimized. The achieved FEM simulations exhibit a remarkably high-predictive potential and allow full control on the vibration behavior of the ultrasonic modules and of the whole transducer. The new transducer is fixed on the wire bonder with a flange whose special geometry was calculated by means of FEM simulations. This flange allows the converter to be attached on the wire bonder not only in longitudinal nodes but also in radial nodes of the ultrasonic field excited in the horn. This leads to a nearly complete decoupling of the transducer to the wire bonder, which has not been previously obtained. The new approach to mount ultrasonic transducers on a welding-device is of major importance not only for wire bonding but also for all high-power ultrasound applications and has been patented.

  13. Advanced welding for closed structure. Pt. 2 The ultrasonic approach

    Energy Technology Data Exchange (ETDEWEB)

    Sacripanti, A.; Paoloni, M.; Sagratella, G. [ENEA Centro Ricerche Casaccia, Rome (Italy). Dipt. Innovazione

    1999-07-01

    This report describes the activities developed for the European Contract BRITE AWCS III to study the use of ultrasonic sensing techniques to obtain an accurate detection of the internal reinforcement of the closed steel structures employed in the shipbuilding industry. After a description of the methods, techniques and problems for the ultrasonic testing of materials in the conventional approach, a new method of the multiple reflection-absorption is introduced with their experimental tests and results. The obtained conclusion shows that the ultrasonic non destructive testing techniques in the new approach should be useful to assemble a complete sensing system with two receivers, one thermal and one ultrasonic. [Italian] Questo rapporto descrive le attivita' sperimentali sviluppate nell'ambito del contratto europeo BRITE AWCS III, in cui si sono utilizzate tecniche ultrasoniche per ottenere un preciso rilevamento dei rinforzi interni di strutture metalliche chiuse utilizzate nell'industria delle costruzioni navali. Dopo la descrizione dei metodi, delle tecniche e dei problemi riguardanti il testing ultrasonico dei materiali, e' stato introdotto un approccio innovativo basato sul metodo dell'assorbimento delle riflessioni multiple con i risultati sperimentali. Le conclusioni ottenute mostrano che nel nuovo approccio, il testing ultrasonico non distruttivo dovrebbe essere utile per assemblare un sistema sensoriale con due sensori, uno di tipo termico, uno di tipo ultrasonico.

  14. Method and device for ultrasonic testing

    International Nuclear Information System (INIS)

    Ultrasonic inspection of the rotor of a gas turbine engine is carried out through a borehole inspection opening, the rotor remaining mounted is the engine. Then the rotor is not accessible for a direct ultrasonic oscillation signal. Therefore a reference signal as well as a reflected signal are picked up by the rotor and compared with one another. The reflected signal is represented visually. (RW) 891 RW/RW 892 GR

  15. Development of an ultrasonic cleaning method for fuel assemblies

    International Nuclear Information System (INIS)

    Almost all radiation buildup in light water reactors is the result of the deposition of activated corrosion and wear products in out-of-core areas. After operation, a significant quantity of corrosion and wear products is deposited on the fuel rods as crud. At refueling shutdowns, these activation products are available for removal. If they can be quickly and easily removed, buildup of radioactivity on out-of-core surfaces and individual exposure dose can be greatly reduced. After studying various physical cleaning methods (e.g., water jet and ultrasonic), the ultrasonic cleaning method was selected as the most effective for fuel assembly cleaning. The ultrasonic cleaning method is especially able to efficiently clean the fuel without removing the channel box. The removed crud in the channel box would be swept out to the filtration unit. Parameter survey tests were carried out to evaluate the optimum conditions for ultrasonic cleaning using a mock-up of a short section of fuel assembly with the channel box. The ultrasonic device used was a 600-W ultrasonic transducer operating at 26-kHz ultrasonic frequency

  16. Development of an ultrasonic cleaning method for fuel assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Heki, H.; Komura, S.; Kato, H.; Sakai, H. (Toshiba Corp., Kawasaki City (Japan)); Hattori, T. (Tokyo Electric Power Co., Kashiwazaki-shi (Japan))

    1991-01-01

    Almost all radiation buildup in light water reactors is the result of the deposition of activated corrosion and wear products in out-of-core areas. After operation, a significant quantity of corrosion and wear products is deposited on the fuel rods as crud. At refueling shutdowns, these activation products are available for removal. If they can be quickly and easily removed, buildup of radioactivity on out-of-core surfaces and individual exposure dose can be greatly reduced. After studying various physical cleaning methods (e.g., water jet and ultrasonic), the ultrasonic cleaning method was selected as the most effective for fuel assembly cleaning. The ultrasonic cleaning method is especially able to efficiently clean the fuel without removing the channel box. The removed crud in the channel box would be swept out to the filtration unit. Parameter survey tests were carried out to evaluate the optimum conditions for ultrasonic cleaning using a mock-up of a short section of fuel assembly with the channel box. The ultrasonic device used was a 600-W ultrasonic transducer operating at 26-kHz ultrasonic frequency.

  17. Development and preliminary study on the ultrasonic assisted GMAW method

    Institute of Scientific and Technical Information of China (English)

    Fan Yangyang; Fan Chenglei; Yang Chunli; Liu Wenge; Lin Sanbao

    2010-01-01

    The ultrasonic assisted GMAW (U-GMAW)method is proposed to achieve a more stable welding process and better weld quality. The U-GMA W system is developed, which consists of power supplies, ultrasonic vibration system and specially de-signed welding torch. The U-GMAW process and conventional GMA W process are compared through bend-on-plate welding.The weld beads are continuous and well protected, while the weld surface appearances by GMA W and U-GMA W are apparently different. The metal transfer mode changes from globular transfer to short-circuiting transfer after ultrasonic wave is applied onto the arc.

  18. Effect of diffraction on the ultrasonic velocity measured by the pulse interference method in VHF range

    Institute of Scientific and Technical Information of China (English)

    WEI Tingcun

    2002-01-01

    The effect of diffraction on the ultrasonic velocity measured by the pulse interference method has been investigated in VHF range theoretically and experimentally. Two silicate glasses are taken as the specimens, their frequency dependences of longitudinal velocities are measured in the frequency range of 50-350 MHz, and the phase advances of ultrasonic signals caused by diffraction effect are calculated using A. O. Williams' theoretical expression. For the velocity error due to diffraction effect, the experimental results are in good agreement with the theoretical prediction. It has been shown that the velocity error due to diffraction effect is directly proportional to d θ21 (f)/df, where θ21 (f) is the phase advances difference between the two partial reflection signals used in velocity measurement and f is the ultrasonic frequency.

  19. Research into Thermal Sprayed Coatings with Ultrasonic Methods

    Directory of Open Access Journals (Sweden)

    Justinas Gargasas

    2012-01-01

    Full Text Available Research on thermal sprayed coatings with ultrasonic methods is the main object of this thesis. Metal surface coating was applied to modify its mechanical and physical-chemical properties and resistance to external impact and improve aesthetics. Spraying was carried out by scanning the rotating sample of 30 cm/s speed. Surface microstructure, ultrasonic thickness, porosity, micro hardness and surface modulus tests performed. Conclusions were formulated.Article in Lithuanian

  20. Research into Thermal Sprayed Coatings with Ultrasonic Methods

    OpenAIRE

    Justinas Gargasas; Irmantas Gedzevičius; Saulius Nagurnas

    2012-01-01

    Research on thermal sprayed coatings with ultrasonic methods is the main object of this thesis. Metal surface coating was applied to modify its mechanical and physical-chemical properties and resistance to external impact and improve aesthetics. Spraying was carried out by scanning the rotating sample of 30 cm/s speed. Surface microstructure, ultrasonic thickness, porosity, micro hardness and surface modulus tests performed. Conclusions were formulated.Article in Lithuanian

  1. Advances in Numerical Methods

    CERN Document Server

    Mastorakis, Nikos E

    2009-01-01

    Features contributions that are focused on significant aspects of current numerical methods and computational mathematics. This book carries chapters that advanced methods and various variations on known techniques that can solve difficult scientific problems efficiently.

  2. Ultrasonic methods for locating hold-up

    International Nuclear Information System (INIS)

    Hold-up remains one of the major contributing factors to unaccounted for materials and can be a costly problem in decontamination and decommissioning activities. Ultrasonic techniques are being developed to noninvasively monitor hold-up in process equipment where the inner surface of such equipment may be in contact with the hold-up material. These techniques may be useful in improving hold-up measurements as well as optimizing decontamination techniques

  3. Advance ultrasonic instrumentation and sensor for tubing industries

    International Nuclear Information System (INIS)

    For thin wall tubing specially in nuclear industry, there are number of institutes/industries provides dimension and flaw detection ultrasonic units. However, full dimension information, for example average ID, OD, wall thickness, true ID, OD, wall thickness, ovality and eccentricity etc. is not available. The paper discusses the state-of-the-art Ultrasonic System and Sensor and its application in tubing industries

  4. Method of manufacturing ultrasonic search units

    International Nuclear Information System (INIS)

    The transducer combs for ultrasonic arrays or compound scanners are fabricated simultaneously from a transducer ground molding, placed on a carrier element, by means of a separating gate with cutting beams of ultrasound or laser radiation. Cutting is performed e.g. on a circular transducer plate in parallel or trapezoidal steps, in rod or mosaic shape. The step intervals in cutting are smaller than 2/4. The contacts between adjoining transducer elements, consisting of e.g. Pb-zirconate-titanate, are soldered to the carrier element of epoxy resin. (DG)

  5. Advanced defect detection algorithm using clustering in ultrasonic NDE

    Science.gov (United States)

    Gongzhang, Rui; Gachagan, Anthony

    2016-02-01

    A range of materials used in industry exhibit scattering properties which limits ultrasonic NDE. Many algorithms have been proposed to enhance defect detection ability, such as the well-known Split Spectrum Processing (SSP) technique. Scattering noise usually cannot be fully removed and the remaining noise can be easily confused with real feature signals, hence becoming artefacts during the image interpretation stage. This paper presents an advanced algorithm to further reduce the influence of artefacts remaining in A-scan data after processing using a conventional defect detection algorithm. The raw A-scan data can be acquired from either traditional single transducer or phased array configurations. The proposed algorithm uses the concept of unsupervised machine learning to cluster segmental defect signals from pre-processed A-scans into different classes. The distinction and similarity between each class and the ensemble of randomly selected noise segments can be observed by applying a classification algorithm. Each class will then be labelled as `legitimate reflector' or `artefacts' based on this observation and the expected probability of defection (PoD) and probability of false alarm (PFA) determined. To facilitate data collection and validate the proposed algorithm, a 5MHz linear array transducer is used to collect A-scans from both austenitic steel and Inconel samples. Each pulse-echo A-scan is pre-processed using SSP and the subsequent application of the proposed clustering algorithm has provided an additional reduction to PFA while maintaining PoD for both samples compared with SSP results alone.

  6. Thickness-Independent Ultrasonic Imaging Applied to Abrasive Cut-Off Wheels: An Advanced Aerospace Materials Characterization Method for the Abrasives Industry. A NASA Lewis Research Center Technology Transfer Case History

    Science.gov (United States)

    Roth, Don J.; Farmer, Donald A.

    1998-01-01

    Abrasive cut-off wheels are at times unintentionally manufactured with nonuniformity that is difficult to identify and sufficiently characterize without time-consuming, destructive examination. One particular nonuniformity is a density variation condition occurring around the wheel circumference or along the radius, or both. This density variation, depending on its severity, can cause wheel warpage and wheel vibration resulting in unacceptable performance and perhaps premature failure of the wheel. Conventional nondestructive evaluation methods such as ultrasonic c-scan imaging and film radiography are inaccurate in their attempts at characterizing the density variation because a superimposing thickness variation exists as well in the wheel. In this article, the single transducer thickness-independent ultrasonic imaging method, developed specifically to allow more accurate characterization of aerospace components, is shown to precisely characterize the extent of the density variation in a cut-off wheel having a superimposing thickness variation. The method thereby has potential as an effective quality control tool in the abrasives industry for the wheel manufacturer.

  7. Advanced differential quadrature methods

    CERN Document Server

    Zong, Zhi

    2009-01-01

    Modern Tools to Perform Numerical DifferentiationThe original direct differential quadrature (DQ) method has been known to fail for problems with strong nonlinearity and material discontinuity as well as for problems involving singularity, irregularity, and multiple scales. But now researchers in applied mathematics, computational mechanics, and engineering have developed a range of innovative DQ-based methods to overcome these shortcomings. Advanced Differential Quadrature Methods explores new DQ methods and uses these methods to solve problems beyond the capabilities of the direct DQ method.After a basic introduction to the direct DQ method, the book presents a number of DQ methods, including complex DQ, triangular DQ, multi-scale DQ, variable order DQ, multi-domain DQ, and localized DQ. It also provides a mathematical compendium that summarizes Gauss elimination, the Runge-Kutta method, complex analysis, and more. The final chapter contains three codes written in the FORTRAN language, enabling readers to q...

  8. Bruce Thompson: Adventures and advances in ultrasonic backscatter

    Science.gov (United States)

    Margetan, Frank J.

    2012-05-01

    Over the course of his professional career Dr. R. Bruce Thompson published several hundred articles on non-destructive evaluation, the majority dealing with topics in ultrasonics. One longtime research interest of Dr. Thompson, with applications both to microstructure characterization and defect detection, was backscattered grain noise in metals. Over a 20 year period he led a revolving team of staff members and graduate students investigating various aspects of ultrasonic backscatter. As a member of that team I had the privilege of working along side Dr. Thompson for many years, serving as a sort of Dr. Watson to Bruce's Sherlock Holmes. This article discusses Dr. Thompson's general approaches to modeling backscatter, the research topics he chose to explore to systematically elucidate a better understanding of the phenomena, and the many contributions to the field achieved under his leadership. The backscatter work began in earnest around 1990, motivated by a need to improve inspections of aircraft engine components. At that time Dr. Thompson launched two research efforts. The first led to the heuristic Independent Scatterer Model which could be used to estimate the average grain noise level that would be seen in any given ultrasonic inspection. There the contribution from the microstructure was contained in a measureable parameter known as the Figure-of-Merit or FOM. The second research effort, spearheaded by Dr. Jim Rose, led to a formal relationship between FOM and details of the metal microstructure. The combination of the Independent Scattering Model and Rose's formalism provided a powerful tool for investigating backscatter in metals. In this article model developments are briefly reviewed and several illustrative applications are discussed. These include: the determination of grain size and shape from ultrasonic backscatter; grain noise variability in engine-titanium billets and forgings; and the design of ultrasonic inspection systems to improve defect

  9. Ultrasonic defect detection method for socket welding joint

    International Nuclear Information System (INIS)

    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.)

  10. The treatment of radioactive wastewater by ultrasonic standing wave method

    Energy Technology Data Exchange (ETDEWEB)

    Su-xia, Hou, E-mail: hsxljj@sina.com; Ji-jun, Luo; Bin, He; Ru-song, Li; Tao, Shen

    2014-06-01

    Highlights: • USWM can be considered as the green cleaning separation techniques. • A physical model of suspended radioactive particle is established. • A computer program is developed to achieve numerical calculation and analysis. • The experimental device for low-level radioactive wastes treatment is designed. • Lots of experimental data are used to analysis the influence of the parameters. - Abstract: The radiation hazards of radionuclide arising from the storage of nuclear weapons cannot be ignored to the operators. Ultrasonic standing wave methods can be considered as the green cleaning separation techniques with high efficiency. The application of ultrasonic standing wave methods for liquid radioactive wastes treatment requires solving many problems connected with the proper selection of the frequency and power of ultrasonic transducers, and the processing time, etc. Based on the model of one single suspended radioactive particle subjected to in the field of ultrasonic standing wave, the principle of the treatment of low-level radioactive wastewater by ultrasound was analyzed. The theoretical and simulation results show that under the action of ultrasonic standing wave, the particle will move toward the wave node plane, and the time of particle reaching the plane become shorter when the radius of particle and the frequency and power of ultrasound was enlarged. The experimental results show that the radioactive concentration of wastewater could be reduced from 400 Bq L{sup −1} to 9.3 Bq L{sup −1} and the decontamination efficiency was 97.68%. The decontamination efficiency could not be obviously improved by further increasing the treating time.

  11. The treatment of radioactive wastewater by ultrasonic standing wave method

    International Nuclear Information System (INIS)

    Highlights: • USWM can be considered as the green cleaning separation techniques. • A physical model of suspended radioactive particle is established. • A computer program is developed to achieve numerical calculation and analysis. • The experimental device for low-level radioactive wastes treatment is designed. • Lots of experimental data are used to analysis the influence of the parameters. - Abstract: The radiation hazards of radionuclide arising from the storage of nuclear weapons cannot be ignored to the operators. Ultrasonic standing wave methods can be considered as the green cleaning separation techniques with high efficiency. The application of ultrasonic standing wave methods for liquid radioactive wastes treatment requires solving many problems connected with the proper selection of the frequency and power of ultrasonic transducers, and the processing time, etc. Based on the model of one single suspended radioactive particle subjected to in the field of ultrasonic standing wave, the principle of the treatment of low-level radioactive wastewater by ultrasound was analyzed. The theoretical and simulation results show that under the action of ultrasonic standing wave, the particle will move toward the wave node plane, and the time of particle reaching the plane become shorter when the radius of particle and the frequency and power of ultrasound was enlarged. The experimental results show that the radioactive concentration of wastewater could be reduced from 400 Bq L−1 to 9.3 Bq L−1 and the decontamination efficiency was 97.68%. The decontamination efficiency could not be obviously improved by further increasing the treating time

  12. An effective segmentation method of ultrasonic thyroid nodules

    Science.gov (United States)

    Du, Wenpeng; Sang, Nong

    2015-12-01

    Segmentation of ultrasound image is an important port of ultrasound medical computer-aided system. However, due to the speckle noise, intensity heterogeneity, and low contrast, the ultrasonic segmentation is much difficult. In this paper, we introduce an effective method which integrates edge phase information and an effective active contour model to make the segmentation better. First, we use the speckle reducing anisotropic diffusion method to suppress the noise in ultrasound images. Then, we utilize the local phase information from monogenic signal to form a novel edge indicator and we use the indicator to replace the traditional intensity-based speed stopping term in distance regularized level set evolution. Another contribution of this paper is that we extend the proposed method to the field of ultrasonic thyroid nodules segmentation, qualitative and quantitative comparative results demonstrate the outperformance of our approach.

  13. Non-destructive evaluation method employing dielectric electrostatic ultrasonic transducers

    Science.gov (United States)

    Yost, William T. (Inventor); Cantrell, Jr., John H. (Inventor)

    2003-01-01

    An acoustic nonlinearity parameter (.beta.) measurement method and system for Non-Destructive Evaluation (NDE) of materials and structural members novelly employs a loosely mounted dielectric electrostatic ultrasonic transducer (DEUT) to receive and convert ultrasonic energy into an electrical signal which can be analyzed to determine the .beta. of the test material. The dielectric material is ferroelectric with a high dielectric constant .di-elect cons.. A computer-controlled measurement system coupled to the DEUT contains an excitation signal generator section and a measurement and analysis section. As a result, the DEUT measures the absolute particle displacement amplitudes in test material, leading to derivation of the nonlinearity parameter (.beta.) without the costly, low field reliability methods of the prior art.

  14. Ultrasonic measurement method of calandria tube sagging in CANDU reactor

    International Nuclear Information System (INIS)

    Calandria tube wrapping each pressure tube is one of the key structural components of CANDU reactor (calandria) which is consisted of many pressure tubes containing nuclear fuel assemblies. As the calandria tube (made of zirconium alloy) is sagging due to its thermal and irradiation creep during the plant operation, it possibly contacts with liquid injection nozzle crossing beneath the calandria tube, which subsequently results in difficulties on the safe operation. It is therefore necessary to check the gap for the confirmation of no contacts between the two tubes, calandria tube and liquid inject ion tube, with a proper measure during the life of plant. In this study, an ultrasonic measurement method was selected among several methods investigated. The ultrasonic device being developed for the measurement of the gap was introduced and its preliminary performance test results were presented here

  15. Multi-wave ultrasonic Doppler method for measuring high flow-rates using staggered pulse intervals

    Science.gov (United States)

    Muramatsu, Ei; Murakawa, Hideki; Sugimoto, Katsumi; Asano, Hitoshi; Takenaka, Nobuyuki; Furuichi, Noriyuki

    2016-02-01

    The ultrasonic pulsed Doppler method (UDM) can obtain a velocity profile along the path of an ultrasonic beam. However, the UDM measurement volume is relatively large and it is known that the measurement volume affects the measurement accuracy. In this study, the effect of the measurement volume on velocity and flow rate measurements is analytically and experimentally evaluated. The velocities measured using UDM are considered to be ensemble-averaged values over the measurement volume in order to analyze the velocity error due to the measurement volume, while the flow rates are calculated from the integration of the velocity profile across the pipe. The analytical results show that the channel width, i.e. the spatial resolution along the ultrasonic beam axis, rather than the ultrasonic beam diameter, strongly influences the flow rate measurement. To improve the accuracy of the flow rate, a novel method using a multi-wave ultrasonic transducer consisting of two piezo-electric elements with different basic frequencies is proposed to minimize the size of the measurement volume in the near-wall region of a pipe flow. The velocity profiles in the near-wall region are measured using an 8 MHz sensor with a small diameter, while those far from the transducer are measured using a hollow 2 MHz sensor in the multi-wave transducer. The applicability of the multi-wave transducer was experimentally investigated using the water flow-rate calibration facility at the National Institute of Advanced Industrial Science and Technology (AIST). As a result, the errors in the flow rate were found to be below  -1%, while the multi-wave method is shown to be particularly effective for measuring higher flow rates in a large-diameter pipe.

  16. Multi-wave ultrasonic Doppler method for measuring high flow-rates using staggered pulse intervals

    International Nuclear Information System (INIS)

    The ultrasonic pulsed Doppler method (UDM) can obtain a velocity profile along the path of an ultrasonic beam. However, the UDM measurement volume is relatively large and it is known that the measurement volume affects the measurement accuracy. In this study, the effect of the measurement volume on velocity and flow rate measurements is analytically and experimentally evaluated. The velocities measured using UDM are considered to be ensemble-averaged values over the measurement volume in order to analyze the velocity error due to the measurement volume, while the flow rates are calculated from the integration of the velocity profile across the pipe. The analytical results show that the channel width, i.e. the spatial resolution along the ultrasonic beam axis, rather than the ultrasonic beam diameter, strongly influences the flow rate measurement. To improve the accuracy of the flow rate, a novel method using a multi-wave ultrasonic transducer consisting of two piezo-electric elements with different basic frequencies is proposed to minimize the size of the measurement volume in the near-wall region of a pipe flow. The velocity profiles in the near-wall region are measured using an 8 MHz sensor with a small diameter, while those far from the transducer are measured using a hollow 2 MHz sensor in the multi-wave transducer. The applicability of the multi-wave transducer was experimentally investigated using the water flow-rate calibration facility at the National Institute of Advanced Industrial Science and Technology (AIST). As a result, the errors in the flow rate were found to be below  −1%, while the multi-wave method is shown to be particularly effective for measuring higher flow rates in a large-diameter pipe. (paper)

  17. Fatigue Crack Measurement in Composite Materials by Ultrasonic Methods

    Science.gov (United States)

    Walker, James L.; Russell, Samuel S.; Suits, Michael W.; Workman, Gary L.; Watson, Jason M.; Thom, Robert (Technical Monitor)

    2002-01-01

    The nondestructive detection of intra-ply microcracking in unlined pressure vessels fabricated from composite materials is critical to ensuring mission success. Microcracking in composite structures due to combined fatigue and cryogenic thermal loading can be very troublesome to detect in-service and when it begins to link through the thickness can cause leakage and failure of the structure. These leaks may lead to loss of pressure/propellant, increased risk of explosion and possible cryo-pumping. The work presented herein develops a method and an instrument to locate and measure intraply fatigue cracking through the thickness of laminated composite material by means of correlation with ultrasonic resonance. Resonant ultrasound spectroscopy provides measurements which are, sensitive to both the microscopic and macroscopic properties of an object. Elastic moduli, acoustic attenuation, and geometry can all be probed. The approach is based on the premise of half-wavelength resonance. The method injects a broadband ultrasonic wave into the test structure using a swept frequency technique. This method provides dramatically increased energy input into the test article, as compared to conventional spike pulsed ultrasonics. This relative energy increase improves the ability to measure finer details in the materials character, such as micro-cracking and porosity. As the micro-crack density increases, more interactions occur with the higher frequency (small wavelength) components of the signal train causing the spectrum to shift toward lower frequencies. Preliminary experiments have verified a measurable effect on the resonance spectrum of the ultrasonic data to detect microcracking. Methods involving self organizing neural networks and other clustering algorithms show that the resonance ultrasound signatures from composites vary with the degree of microcracking and can be separated and identified.

  18. A new ultrasonic signal amplification method for detection of bacteria

    International Nuclear Information System (INIS)

    A new method is presented that increases the sensitivity of ultrasound-based techniques for detection of bacteria. The technique was developed for the detection of catalase-positive microorganisms. It uses a bubble trapping medium containing hydrogen peroxide that is mixed with the sample for microbiological evaluation. The enzyme catalase is present in catalase-positive bacteria, which induces a rapid hydrolysis of hydrogen peroxide, forming bubbles which remain in the medium. This reaction results in the amplification of the mechanical changes that the microorganisms produce in the medium. The effect can be detected by means of ultrasonic wave amplitude continuous measurement since the bubbles increase the ultrasonic attenuation significantly. It is shown that microorganism concentrations of the order of 105 cells ml−1 can be detected using this method. This allows an improvement of three orders of magnitude in the ultrasonic detection threshold of microorganisms in conventional culture media, and is competitive with modern rapid microbiological methods. It can also be used for the characterization of the enzymatic activity. (paper)

  19. Materials characterization by resonant ultrasonic spectroscopy method

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Yong Moo; Jung, H.K.; Joo, Y.S.; Sim, C.M

    2001-01-01

    A high temperature resonant ultrasound spectroscopy(RUS) was developed. The dynamic elastic constant of RPV weld, which has various different microstructure was determined by RUS. It was confirmed the RUS method is very sensitive to the microstructures of the material. RUS can be used to monitor the degradation of nuclear materials including neutron irradiation embrittlement through the measurement of dynamic elastic constants, elastic anisotropy, high temperature elastic constant and Q-factor.

  20. Materials characterization by resonant ultrasonic spectroscopy method

    International Nuclear Information System (INIS)

    A high temperature resonant ultrasound spectroscopy(RUS) was developed. The dynamic elastic constant of RPV weld, which has various different microstructure was determined by RUS. It was confirmed the RUS method is very sensitive to the microstructures of the material. RUS can be used to monitor the degradation of nuclear materials including neutron irradiation embrittlement through the measurement of dynamic elastic constants, elastic anisotropy, high temperature elastic constant and Q-factor

  1. Ultrasonic inspection methods for small-bore applications

    International Nuclear Information System (INIS)

    The nondestructive inspection of tubing and tube-to-tubesheet weldments in heat exchangers for reactor systems is necessary to ensure the high integrity essential for safe, reliable, continuously operating units. An ultrasonic inspection system has been developed for small-bore applications. The current system can be used to inspect tubing or weldments with bores as small as 10.1 mm (0.4 in.) for transversely or longitudinally oriented discontinuities; however, similar inspections are possible within even smaller bores. Since the probe head is rotated to provide inspection along a helical path, special ultrasonic signal connectors are employed. The miniature probe heads employed are designed for rapid exchange in the mechanical scanner. These probes use commercially available transducers and are capable of performing various ultrasonic inspections with both single and dual examination techniques. The inspection methods and equipment are discussed, along with results of calibration, recording, and correlation studies performed on laboratory-type specimens. Reference notches with depths representing 2 percent of the wall thickness were detected and recorded from the bore of 15.88 mm OD x 2.77 mm wall (0.625 x 0.109 in.) tubing

  2. Advanced instrumentation for acousto-ultrasonic based structural health monitoring

    Science.gov (United States)

    Smithard, Joel; Galea, Steve; van der Velden, Stephen; Powlesland, Ian; Jung, George; Rajic, Nik

    2016-04-01

    Structural health monitoring (SHM) systems using structurally-integrated sensors potentially allow the ability to inspect for damage in aircraft structures on-demand and could provide a basis for the development of condition-based maintenance approaches for airframes. These systems potentially offer both substantial cost savings and performance improvements over conventional nondestructive inspection (NDI). Acousto-ultrasonics (AU), using structurallyintegrated piezoelectric transducers, offers a promising basis for broad-field damage detection in aircraft structures. For these systems to be successfully applied in the field the hardware for AU excitation and interrogation needs to be easy to use, compact, portable, light and, electrically and mechanically robust. Highly flexible and inexpensive instrumentation for basic background laboratory investigations is also required to allow researchers to tackle the numerous scientific and engineering issues associated with AU based SHM. The Australian Defence Science and Technology Group (DST Group) has developed the Acousto Ultrasonic Structural health monitoring Array Module (AUSAM+), a compact device for AU excitation and interrogation. The module, which has the footprint of a typical current generation smart phone, provides autonomous control of four send and receive piezoelectric elements, which can operate in pitch-catch or pulse-echo modes and can undertake electro-mechanical impedance measurements for transducer and structural diagnostics. Modules are designed to operate synchronously with other units, via an optical link, to accommodate larger transducer arrays. The module also caters for fibre optic sensing of acoustic waves with four intensity-based optical inputs. Temperature and electrical resistance strain gauge inputs as well as external triggering functionality are also provided. The development of a Matlab hardware object allows users to easily access the full hardware functionality of the device and

  3. Ultrasonic NDE Classifications with the Gradient Descent Method and Synthetic Aperture Focusing Technique

    International Nuclear Information System (INIS)

    Ultrasonic inspection methods are widely used for detecting flaws in materials. One of the more popular methods involves the extraction of an appropriate set of features followed by the use of a neural network for the classification of the signals in the feature space. This paper describes an approach which uses LMS method to determine the coordinates of the ultrasonic probe followed by the use of SAFT to estimate the location of the ultrasonic reflector. The method is employed for classifying NDE signals from the steam generator tubes in a nuclear power plant. The classification results using this scheme for the ultrasonic signals from cracks and deposits within steam generator tubes are presented

  4. Welding apparatus and methods for using ultrasonic sensing

    Science.gov (United States)

    McJunkin, Timothy R.; Johnson, John A.; Larsen, Eric D.; Smartt, Herschel B.

    2006-08-22

    A welding apparatus using ultrasonic sensing is described and which includes a movable welder having a selectively adjustable welding head for forming a partially completed weld in a weld seam defined between adjoining metal substrates; an ultrasonic assembly borne by the moveable welder and which is operable to generate an ultrasonic signal which is directed toward the partially completed weld, and is further reflected from same; and a controller electrically coupled with the ultrasonic assembly and controllably coupled with the welding head, and wherein the controller receives information regarding the ultrasonic signal and in response to the information optimally positions the welding head relative to the weld seam.

  5. Monitoring of concrete structures using the ultrasonic pulse velocity method

    Science.gov (United States)

    Karaiskos, G.; Deraemaeker, A.; Aggelis, D. G.; Van Hemelrijck, D.

    2015-11-01

    Concrete is the material most produced by humanity. Its popularity is mainly based on its low production cost and great structural design flexibility. Its operational and ambient loadings including environmental effects have a great impact in the performance and overall cost of concrete structures. Thus, the quality control, the structural assessment, the maintenance and the reliable prolongation of the operational service life of the existing concrete structures have become a major issue. In the recent years, non-destructive testing (NDT) is becoming increasingly essential for reliable and affordable quality control and integrity assessment not only during the construction of new concrete structures, but also for the existing ones. Choosing the right inspection technique is always followed by a compromise between its performance and cost. In the present paper, the ultrasonic pulse velocity (UPV) method, which is the most well known and widely accepted ultrasonic concrete NDT method, is thoroughly reviewed and compared with other well-established NDT approaches. Their principles, inherent limitations and reliability are reviewed. In addition, while the majority of the current UPV techniques are based on the use of piezoelectric transducers held on the surface of the concrete, special attention is paid to a very promising technique using low-cost and aggregate-size piezoelectric transducers embedded in the material. That technique has been evaluated based on a series of parameters, such as the ease of use, cost, reliability and performance.

  6. Advanced non-destructive methods for an efficient service performance

    International Nuclear Information System (INIS)

    Due to the power generation industry's desire to decrease outage time and extend inspection intervals for highly stressed turbine parts, advanced and reliable Non-destructive methods were developed by Siemens Non-destructive laboratory. Effective outage performance requires the optimized planning of all outage activities as well as modern Non-destructive examination methods, in order to examine the highly stressed components (turbine rotor, casings, valves, generator rotor) reliably and in short periods of access. This paper describes the experience of Siemens Energy with an ultrasonic Phased Array inspection technique for the inspection of radial entry pinned turbine blade roots. The developed inspection technique allows the ultrasonic inspection of steam turbine blades without blade removal. Furthermore advanced Non-destructive examination methods for joint bolts will be described, which offer a significant reduction of outage duration in comparison to conventional inspection techniques. (authors)

  7. Thermal dispersion method for an ultrasonic phased-array transducer

    Science.gov (United States)

    Choi, Euna; Lee, Wonseok; Roh, Yongrae

    2016-07-01

    When the driving voltage of an ultrasonic transducer is increased to improve the quality of ultrasound images, heat is generated inside the transducer, which can burn the patient’s skin and degrade transducer performance. In this study, the method to disperse the heat inside an ultrasonic phased-array transducer has been examined. The mechanism of temperature rise due to heat generation inside the transducer was investigated by numerical analysis and the effects of the thermal properties of the components of the transducer such as specific heat and thermal conductivity on the temperature rise were analyzed. On the basis of the results, a heat-dispersive structure was devised to reduce the temperature at the surface of the acoustic lens of the transducer. Prototype transducers were fabricated to check the efficacy of the heat-dispersive structure. By experiments, we have confirmed that the new heat-dispersive structure can reduce the internal temperature by as much as 50% in comparison with the conventional structure, which confirms the validity of the thermal dispersion mechanism developed in this work.

  8. The Elastic Constants Measurement of Metal Alloy by Using Ultrasonic Nondestructive Method at Different Temperature

    Directory of Open Access Journals (Sweden)

    Eryi Hu

    2016-01-01

    Full Text Available The ultrasonic nondestructive method is introduced into the elastic constants measurement of metal material. The extraction principle of Poisson’s ratio, elastic modulus, and shear modulus is deduced from the ultrasonic propagating equations with two kinds of vibration model of the elastic medium named ultrasonic longitudinal wave and transverse wave, respectively. The ultrasonic propagating velocity is measured by using the digital correlation technique between the ultrasonic original signal and the echo signal from the bottom surface, and then the elastic constants of the metal material are calculated. The feasibility of the correlation algorithm is verified by a simulation procedure. Finally, in order to obtain the stability of the elastic properties of different metal materials in a variable engineering application environment, the elastic constants of two kinds of metal materials in different temperature environment are measured by the proposed ultrasonic method.

  9. Characteristic Evaluation on Bolt Stress by Ultrasonic Nondestructive Methods

    Directory of Open Access Journals (Sweden)

    Qinxue Pan

    2015-01-01

    Full Text Available Based on the acoustoelasticity theory, a certain relationship exists between ultrasonic velocity and stress. By combining shear and longitudinal waves, this paper provides a nondestructive method of evaluating axial stress in a tightened bolt. For measuring the bolt axial stress in different situations, such as under low or high loads, this paper provides guidelines for calculating the stress for a given load factor. Experimental and calculated results were compared for three bolt test samples: an austenitic stainless steel bolt (A2-70 and low-carbon steel 4.8 and 8.8 bolts. On average, the experimental results were in good agreement with those obtained through calculations, thus providing a nondestructive method for bolt stress measurements.

  10. Ultrasonic materials characterization

    Science.gov (United States)

    Smith, R. L.

    1987-02-01

    The National NDT Center at Harwell has been developing methods for the characterization of materials using ultrasonics. This paper reviews the progress made in applying ultrasonic attenuation measurements to the determination of such quantities as grain size and dislocation content. A method, ultrasonic attenuation spectral analysis, has been developed, which enables the contributions of scattering and absorption to the total attenuation to be separated. The theoretical advances that have been made are also described. Some of the practical applications of the technique are illustrated and future development discussed.

  11. Measuring mass density and ultrasonic wave velocity: A wavelet-based method applied in ultrasonic reflection mode.

    Science.gov (United States)

    Metwally, Khaled; Lefevre, Emmanuelle; Baron, Cécile; Zheng, Rui; Pithioux, Martine; Lasaygues, Philippe

    2016-02-01

    When assessing ultrasonic measurements of material parameters, the signal processing is an important part of the inverse problem. Measurements of thickness, ultrasonic wave velocity and mass density are required for such assessments. This study investigates the feasibility and the robustness of a wavelet-based processing (WBP) method based on a Jaffard-Meyer algorithm for calculating these parameters simultaneously and independently, using one single ultrasonic signal in the reflection mode. The appropriate transmitted incident wave, correlated with the mathematical properties of the wavelet decomposition, was determined using a adapted identification procedure to build a mathematically equivalent model for the electro-acoustic system. The method was tested on three groups of samples (polyurethane resin, bone and wood) using one 1-MHz transducer. For thickness and velocity measurements, the WBP method gave a relative error lower than 1.5%. The relative errors in the mass density measurements ranged between 0.70% and 2.59%. Despite discrepancies between manufactured and biological samples, the results obtained on the three groups of samples using the WBP method in the reflection mode were remarkably consistent, indicating that it is a reliable and efficient means of simultaneously assessing the thickness and the velocity of the ultrasonic wave propagating in the medium, and the apparent mass density of material. PMID:26403278

  12. Method and system having ultrasonic sensor movable by translation device for ultrasonic profiling of weld samples

    Science.gov (United States)

    Panyard, James; Potter, Timothy; Charron, William; Hopkins, Deborah; Reverdy, Frederic

    2010-04-06

    A system for ultrasonic profiling of a weld sample includes a carriage movable in opposite first and second directions. An ultrasonic sensor is coupled to the carriage to move over the sample as the carriage moves. An encoder determines the position of the carriage to determine the position of the sensor. A spring is connected at one end of the carriage. Upon the carriage being moved in the first direction toward the spring such that the carriage and the sensor are at a beginning position and the spring is compressed the spring decompresses to push the carriage back along the second direction to move the carriage and the sensor from the beginning position to an ending position. The encoder triggers the sensor to take the ultrasonic measurements of the sample when the sensor is at predetermined positions while the sensor moves over the sample between the beginning and positions.

  13. Electronic device for specimens testing by ultrasonic resonance method

    International Nuclear Information System (INIS)

    A device for processing of electric signals, which permits to measure a number of characteristics of ultrasonic oscillations, is described. The electron device developed in combination with standard apparatus can be used for out-of-reactor and in-reactor ultrasonic investigations of material and articles, in particular, for the control of defects in nuclear fuel pellets

  14. Ultrasonic defect-sizing using decibel drop methods. I

    International Nuclear Information System (INIS)

    Results are reported of a study performed to investigate the accuracy and repeatability of various ultrasonic decibel (dB) drop sizing methods in determining the length, vertical extent and orientation of artificial and real weld flaws in thin steel sections. Seven artificial flaws and nine real weld flaws were examined; over 200 data plots were produced. The general findings are: a) length and vertical extent are assessed most accurately when using a 14 dB drop from the maximum indication amplitude; b) decibel drops less that 14 dB generally undersize flaws while decibel drops greater than 14 dB generally oversize flaws; c) flaws which are smaller than the width of the sound beam cannot be assessed accurately using dB drop methods; d) large flaws are assessed most accurately when the sound beam strikes the flaws at near normal incidence; e) the vertical extent and orientation of large flaws are plotted most accurately using the beam centre line method as opposed to the beam profile method; and, f) the limitations of dB-drop-sizing methods have considerable ramifications for CAN3-N285.4-M83 and ASME XI evaluation criteria

  15. Toxicity of coke wastewater treated with advanced oxidation by Fenton process supported by ultrasonic field

    OpenAIRE

    Kwarciak-Kozłowska Anna; Krzywicka Aleksandra

    2016-01-01

    The aim of the presented study was to determine the toxicity of wastewater from the production of coke. The wastewater was treated with advanced oxidation involving ultrasonic field with Fenton’s reagent (the amplitude was 61.5 μm and sonication time 8 min). Two doses of iron and four doses of hydrogen peroxide were used. The amount of hydrogen peroxide was proportional to the value of the chemical oxygen demand of raw wastewater, ranging from COD/H2O2 ratio of 1:2.5 to 1:20. Two tests were u...

  16. Advances in energy harvesting methods

    CERN Document Server

    Elvin, Niell

    2012-01-01

    Advances in Energy Harvesting Methods presents a state-of-the-art understanding of diverse aspects of energy harvesting with a focus on: broadband energy conversion, new concepts in electronic circuits, and novel materials. This book covers recent advances in energy harvesting using different transduction mechanisms; these include methods of performance enhancement using nonlinear effects, non-harmonic forms of excitation and non-resonant energy harvesting, fluidic energy harvesting, and advances in both low-power electronics as well as  material science. The contributors include a brief liter

  17. Enhancing the adhesion strength of micro electroforming layer by ultrasonic agitation method and the application.

    Science.gov (United States)

    Zhao, Zhong; Du, Liqun; Tao, Yousheng; Li, Qingfeng; Luo, Lei

    2016-11-01

    Micro electroforming is widely used for fabricating micro metal devices in Micro Electro Mechanism System (MEMS). However, there is the problem of poor adhesion strength between micro electroforming layer and substrate. This dramatically influences the dimensional accuracy of the device. To solve this problem, ultrasonic agitation method is applied during the micro electroforming process. To explore the effect of the ultrasonic agitation on the adhesion strength, micro electroforming experiments were carried out under different ultrasonic power (0W, 100W, 150W, 200W, 250W) and different ultrasonic frequencies (0kHz, 40kHz, 80kHz, 120kHz, 200kHz). The effects of the ultrasonic power and the ultrasonic frequency on the micro electroforming process were investigated by polarization method and alternating current (a.c.) impedance method. The adhesion strength between the electroforming layer and the substrate was measured by scratch test. The compressive stress of the electroforming layer was measured by X-ray Diffraction (XRD) method. The crystallite size of the electroforming layer was measured by Transmission Electron Microscopy (TEM) method. The internal contact surface area of the electroforming layer was measured by cyclic voltammetry (CV) method. The experimental results indicate that the ultrasonic agitation can decrease the polarization overpotential and increase the charge transfer process. Generally, the internal contact surface area is increased and the compressive stress is reduced. And then the adhesion strength is enhanced. Due to the different depolarization effects of the ultrasonic power and the ultrasonic frequency, the effects on strengthening the adhesion strength are different. When the ultrasonic agitation is 200W and 40kHz, the effect on strengthening the adhesion strength is the best. In order to prove the effect which the ultrasonic agitation can improve the adhesion strength of the micro devices, micro pillar arrays were fabricated under

  18. TECHNOLOGY OF QUANTITATIVE ANALYSIS ON VIBRATORY STRESS RELIEF BASED ON ULTRASONIC TIME-OF-ARRIVAL METHOD

    Institute of Scientific and Technical Information of China (English)

    He Wen; Ma Zhenyu; Wang Xingli

    2005-01-01

    The effect of vibratory stress relief (VSR) is usually evaluated with the indirect method of observing the change of amplitude frequency response characteristics of structures. A new kind of evaluating method of VSR based on the ultrasonic time-of-arrival method (UTM), which can obtain the residual stress directly through measuring the propagation time of ultrasonic wave in the material, is presented. At first, the principle of the measuring method of residual stress based on UTM is analyzed. Then the measuring system of the method is described, which is in virtue of ultrasonic flaw detector and high-sampling-rate digital oscillograph. And a set of calibration system that contains a piece of standard specimen is also introduced. Experimental results prove the relation between the residual stress and the propagation time of ultrasonic in workpieces. Finally, the measuring and calibration systems are applied in evaluating the effect of VSR. The final test results show that the method is effective.

  19. Ultrasonically controlled particle size distribution of explosives: a safe method.

    Science.gov (United States)

    Patil, Mohan Narayan; Gore, G M; Pandit, Aniruddha B

    2008-03-01

    Size reduction of the high energy materials (HEM's) by conventional methods (mechanical means) is not safe as they are very sensitive to friction and impact. Modified crystallization techniques can be used for the same purpose. The solute is dissolved in the solvent and crystallized via cooling or is precipitated out using an antisolvent. The various crystallization parameters such as temperature, antisolvent addition rate and agitation are adjusted to get the required final crystal size and morphology. The solvent-antisolvent ratio, time of crystallization and yield of the product are the key factors for controlling antisolvent based precipitation process. The advantages of cavitationally induced nucleation can be coupled with the conventional crystallization process. This study includes the effect of the ultrasonically generated acoustic cavitation phenomenon on the solvent antisolvent based precipitation process. CL20, a high-energy explosive compound, is a polyazapolycyclic caged polynitramine. CL-20 has greater energy output than existing (in-use) energetic ingredients while having an acceptable level of insensitivity to shock and other external stimuli. The size control and size distribution manipulation of the high energy material (CL20) has been successfully carried out safely and quickly along with an increase in the final mass yield, compared to the conventional antisolvent based precipitation process. PMID:17532248

  20. Dyeing of Organic Cotton Fabric using Conventional and Ultrasonic Exhaust Dyeing Method

    Directory of Open Access Journals (Sweden)

    Uzma Syed

    2013-04-01

    Full Text Available In this research dyeing behavior of organic cotton woven fabric using ultrasonic technique and conventional dyeing method has been compared. The fabric samples were dyed with reactive dyes Drimarene Red Cl-5B and Drimarene Blue Cl-BR (0.5% owf using exhaust dyeing method. The samples were ultrasonically dyed at varied temperature (60, 50 and 40oC for 60, 50, 40 and 30 minutes and for conventional method at varied temperature but at recommended time, 60 minutes. For optimizing the dyeing behavior, the samples were causticized by pad-batch method and then dyed with ultrasonic technique at varied temperature and time. It has been observed organic cotton fabric dyed using ultrasonic exhaust method at 60oC for 50 minutes gives highest (K/S?max value, excellent fastness property, deeper dye diffusion and less surface deterioration compared to the conventional dyeing method. Moreover, causticized and dyed sample with ultrasonic technique at 60oC for 30 minutes gives colour strength value almost equal to the conventional recommended dyeing method. Hence, dyeing of organic material using ultrasonic exhaust method saves energy and time

  1. Application of nonlinear ultrasonic method for monitoring of stress state in concrete

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Gyu Jin; Kwak, Hyo Gyoung [Dept. of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Park, Sun Jong [Dept. of Structural System and Site Safety Evaluation, Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2016-04-15

    As the lifespan of concrete structures increases, their load carrying capacity decreases owing to cyclic loads and long-term effects such as creep and shrinkage. For these reasons, there is a necessity for stress state monitoring of concrete members. Particularly, it is necessary to evaluate the concrete structures for behavioral changes by using a technique that can overcome the measuring limitations of usual ultrasonic nondestructive evaluation methods. This paper proposes the use of a nonlinear ultrasonic method, namely, nonlinear resonant ultrasonic spectroscopy (NRUS) for the measurement of nonlinearity parameters for stress monitoring. An experiment compared the use of NRUS method and a linear ultrasonic method, namely, ultrasonic pulse velocity (UPV) to study the effects of continuously increasing loads and cyclic loads on the nonlinearity parameter. Both NRUS and UPV methods found a similar direct relationship between load level and that parameter. The NRUS method showed a higher sensitivity to micro-structural changes of concrete than UPV method. Thus, the experiment confirms the possibility of using the nonlinear ultrasonic method for stress state monitoring of concrete members.

  2. Single Transducer Ultrasonic Imaging Method that Eliminates the Effect of Plate Thickness Variation in the Image

    Science.gov (United States)

    Roth, Don J.

    1996-01-01

    This article describes a single transducer ultrasonic imaging method that eliminates the effect of plate thickness variation in the image. The method thus isolates ultrasonic variations due to material microstructure. The use of this method can result in significant cost savings because the ultrasonic image can be interpreted correctly without the need for machining to achieve precise thickness uniformity during nondestructive evaluations of material development. The method is based on measurement of ultrasonic velocity. Images obtained using the thickness-independent methodology are compared with conventional velocity and c-scan echo peak amplitude images for monolithic ceramic (silicon nitride), metal matrix composite and polymer matrix composite materials. It was found that the thickness-independent ultrasonic images reveal and quantify correctly areas of global microstructural (pore and fiber volume fraction) variation due to the elimination of thickness effects. The thickness-independent ultrasonic imaging method described in this article is currently being commercialized under a cooperative agreement between NASA Lewis Research Center and Sonix, Inc.

  3. Specific ultrasonic inspection methods for steam generator tubes

    International Nuclear Information System (INIS)

    Framatome has developed a computerized equipment for inspecting PWR steam generator tubes using a rotating ultrasonic probe. Firstly devoted to the examination of the roll transition zone at the tube sheet secondary side level, the testing system can also operate now for inspections at the tube support plate levels. It is used independently for specific tube inspection, or it can be integrated into a broader-purpose system for sleeve weld testing, etc. The testing results are displayed in real time by means of two eight-level coded colored maps. Some applications, ranging from mockup testing to on-site inspection, are presented in this paper. In conclusion: An automated ultrasonic real-time imaging system for tube-wall thickness measurement, internal profilometry, and flaw detection, has been developed. This system has been successfully applied for on-site specific inspections within an industrial environment. In all cases the ultrasonic acquisition time was less than two minutes per tube. It should be pointed out that analysis of this new set of ultrasonic inspection results should also improve understanding of the in-service behaviour of these materials and components

  4. A new measurement method for ultrasonic surface roughness measurements

    DEFF Research Database (Denmark)

    Forouzbakhsh, Farshid; Rezanejad Gatabi, Javad; Rezanejad Gatabi, Iman

    2008-01-01

    an ultrasonic transmitter emits sound pulses that travel across to the under-test surface. The reflected wave is separated into many weak sounds, a few of which are received by the receiver. The Doppler effect caused the frequency of the received wave to be shifted with respect to the surface roughness...

  5. Production of Biodiesel from Lipid of Phytoplankton Chaetoceros calcitrans through Ultrasonic Method

    OpenAIRE

    Raymond Kwangdinata; Indah Raya; Muhammad Zakir

    2014-01-01

    A research on production of biodiesel from lipid of phytoplankton Chaetoceros calcitrans through ultrasonic method has been done. In this research, we carried out a series of phytoplankton cultures to determine the optimum time of growth and biodiesel synthesis process from phytoplankton lipids. Process of biodiesel synthesis consists of two steps, that is, isolation of phytoplankton lipids and biodiesel synthesis from those lipids. Oil isolation process was carried out by ultrasonic extracti...

  6. A Wavelet-Based Processing method for simultaneously determining ultrasonic velocity and material thickness

    OpenAIRE

    Loosvelt, Matthieu; Lasaygues, Philippe

    2011-01-01

    Methods of measuring ultrasonic wave velocity in an elastic sample require data on the thickness of the sample and/or the distances between the transducers and the sample. The uncertainty of the ultrasonic wave velocity measurements generally depends on that of the data available. Conversely, to determine the thickness of a material, it is necessary to have a priori information about the wave velocity. This problem is particularly hard to solve when measuring the parameters of biological spec...

  7. Toxicity of coke wastewater treated with advanced oxidation by Fenton process supported by ultrasonic field

    Directory of Open Access Journals (Sweden)

    Kwarciak-Kozłowska Anna

    2016-03-01

    Full Text Available The aim of the presented study was to determine the toxicity of wastewater from the production of coke. The wastewater was treated with advanced oxidation involving ultrasonic field with Fenton’s reagent (the amplitude was 61.5 μm and sonication time 8 min. Two doses of iron and four doses of hydrogen peroxide were used. The amount of hydrogen peroxide was proportional to the value of the chemical oxygen demand of raw wastewater, ranging from COD/H2O2 ratio of 1:2.5 to 1:20. Two tests were used to determine the toxicity (algae growth inhibition test and Lepidium test. It was found that more toxic to algae was wastewater treated by Fenton’s reagent containing a higher dose of iron. A similar inhibitory effect was observed on the germination of cress seeds.

  8. Application of laser ultrasonic method for on-line monitoring of friction stir spot welding process.

    Science.gov (United States)

    Zhang, Kuanshuang; Zhou, Zhenggan; Zhou, Jianghua

    2015-09-01

    Application of a laser ultrasonic method is developed for on-line monitoring of the friction stir spot welding (FSSW) process. Based on the technology of FSSW, laser-generated ultrasonic waves in a good weld and nonweld area are simulated by a finite element method. The reflected and transmitted waves are analyzed to disclose the properties of the welded interface. The noncontact-laser ultrasonic-inspection system was established to verify the numerical results. The reflected waves in the good-weld and nonweld area can be distinguished by time-of-flight. The transmitted waves evidently attenuate in the nonweld area in contrast to signal amplitude in the good weld area because of interfacial impedance difference. Laser ultrasonic C-scan images can sufficiently evaluate the intrinsic character of the weld area in comparison with traditional water-immersion ultrasonic testing results. The research results confirm that laser ultrasonics would be an effective method to realize the characterization of FSSW defects. PMID:26368866

  9. Application of laser ultrasonic method for on-line monitoring of friction stir spot welding process.

    Science.gov (United States)

    Zhang, Kuanshuang; Zhou, Zhenggan; Zhou, Jianghua

    2015-09-01

    Application of a laser ultrasonic method is developed for on-line monitoring of the friction stir spot welding (FSSW) process. Based on the technology of FSSW, laser-generated ultrasonic waves in a good weld and nonweld area are simulated by a finite element method. The reflected and transmitted waves are analyzed to disclose the properties of the welded interface. The noncontact-laser ultrasonic-inspection system was established to verify the numerical results. The reflected waves in the good-weld and nonweld area can be distinguished by time-of-flight. The transmitted waves evidently attenuate in the nonweld area in contrast to signal amplitude in the good weld area because of interfacial impedance difference. Laser ultrasonic C-scan images can sufficiently evaluate the intrinsic character of the weld area in comparison with traditional water-immersion ultrasonic testing results. The research results confirm that laser ultrasonics would be an effective method to realize the characterization of FSSW defects.

  10. Critical review of advanced decontamination methods and their application and selection of methods suitable for disposal decontamination

    International Nuclear Information System (INIS)

    The report is structured as follows: (i) Critical review of advanced decontamination methods (chemical methods; electrochemical methods; mechanical methods - high-pressure water jet, abrasive methods, ultrasonic methods); (ii) Effective management of the entire decontamination process; (iii) Proposal for advanced decontamination methods suitable for disposal decontamination; and (iv) Effect of decontamination on waste management. It is concluded that (i) No single universal method exists for efficient decontamination of different materials, so a combination of methods must be used; (ii) The decontamination process should be optimised so that its cost should not exceed the cost of contaminated material handling without decontamination. The following methods were selected for additional examination: dry abrasive blasting, chemical decontamination, and ultrasonic decontamination. (P.A.)

  11. Characterisation of CFRP Through Enhanced Ultrasonic Testing Methods

    Science.gov (United States)

    Helfen, T. B.; Venkat, R. Sridaran; Rabe, U.; Hirsekorn, S.; Boller, C.

    2012-12-01

    Carbon fibre reinforced composite materials enjoy an increasing field of application in the aeronautical environment and are due to expand into the automotive and leisure sectors in due course. Those materials need to be qualified at reasonable cost and with considerable experience, where ultrasonic testing has become the procedure of primary choice for nondestructive testing (NDT) so far. However, the two-phase anisotropic structure of a composite material implies a variety of challenges such as scattering, beam skewing, and sound field distortion complicating the localization, sizing, and characterization of defects. Besides qualification during the manufacturing stage, additional tasks emerge once the composite material ages, maybe by mechanical fatigue, chemical ageing, or irradiation. Again characterisation of the material based on ultrasonics would allow comparisons to be made along a material's life cycle. The knowledge generated could be used for in-situ monitoring procedures such as considered in the context of structural health monitoring (SHM).

  12. Self-calibration method for rotating laser positioning system using interscanning technology and ultrasonic ranging.

    Science.gov (United States)

    Wu, Jun; Yu, Zhijing; Zhuge, Jingchang

    2016-04-01

    A rotating laser positioning system (RLPS) is an efficient measurement method for large-scale metrology. Due to multiple transmitter stations, which consist of a measurement network, the position relationship of these stations must be first calibrated. However, with such auxiliary devices such as a laser tracker, scale bar, and complex calibration process, the traditional calibration methods greatly reduce the measurement efficiency. This paper proposes a self-calibration method for RLPS, which can automatically obtain the position relationship. The method is implemented through interscanning technology by using a calibration bar mounted on the transmitter station. Each bar is composed of three RLPS receivers and one ultrasonic sensor whose coordinates are known in advance. The calibration algorithm is mainly based on multiplane and distance constraints and is introduced in detail through a two-station mathematical model. The repeated experiments demonstrate that the coordinate measurement uncertainty of spatial points by using this method is about 0.1 mm, and the accuracy experiments show that the average coordinate measurement deviation is about 0.3 mm compared with a laser tracker. The accuracy can meet the requirements of most applications, while the calibration efficiency is significantly improved. PMID:27140762

  13. Recent advances in ultrasonic downcomer flow-measurement techniques for recirculating steam generators

    International Nuclear Information System (INIS)

    Non-intrusive ultrasonic measurements of downcomer flow velocity have been successfully used in the past to determine recirculation ratios and water inventory in CANDU steam generators. Knowledge of these process conditions allows operators to assess the effectiveness of maintenance programs, monitor the effects of tube fouling, and observe flow conditions following component modifications. It also provides designers with a means to verify or improve code predictions. Ultrasonic measurement systems have recently been installed on sixteen steam generators at the Bruce B Nuclear Generating Station, as part of an investigation into the possible effects of long-term boiler degradation. The most recent version of AECL's downcomer-flow technology was used, which features high-temperature transducers that are attached magnetically and then welded to the steam-generator outer shell. This method eliminates the complications of precision surface preparation, high-temperature couplants and awkward mechanical attachments. The paper will outline the method and summarize flow velocities measured during normal operation, over extended periods of time. It will also describe how the information might be used, e.g., to assess thermalhydraulic conditions, verify design calculations and support the case for reactor uprating. Further improvements that may allow the reliable measurement of flow in steam generators with steam carry-under are suggested, and preliminary results are presented from a dual-purpose single- and two-phase flow-measurement system. (author)

  14. New Generation of High Resolution Ultrasonic Imaging Technique for Advanced Material Characterization: Review

    Science.gov (United States)

    Maev, R. Gr.

    The role of non-destructive material characterization and NDT is changing at a rapid rate, continuing to evolve alongside the dramatic development of novel techniques based on the principles of high-resolution imaging. The modern use of advanced optical, thermal, ultrasonic, laser-ultrasound, acoustic emission, vibration, electro-magnetic, and X-ray techniques, etc., as well as refined measurement and signal/data processing devices, allows for continuous generation of on-line information. As a result real-time process monitoring can be achieved, leading to the more effective and efficient control of numerous processes, greatly improving manufacturing as a whole. Indeed, concurrent quality inspection has become an attainable reality. With the advent of new materials for use in various structures, joints, and parts, however, innovative applications of modern NDT imaging techniques are necessary to monitor as many stages of manufacturing as possible. Simply put, intelligent advance manufacturing is impossible without actively integrating modern non-destructive evaluation into the production system.

  15. The Testing Strength Curves of Lightweight Aggregate Concrete by Rebound Method and Ultrasonic-rebound Combined Method

    Institute of Scientific and Technical Information of China (English)

    RONG Hui; QIAN Chunxiang; GAO Lixiong; HAN Jiande; WANG Caihui

    2011-01-01

    The strength curves of lightweight aggregate concrete (LWAC) were tested based on detecting LWAC with density of 1 400-1 900 kg/m3 and LWAC with strength grade of LCI5-LC50 by rebound method and ultrasonic-rebound combined method.The results show that the common measured strength curves tested by above two methods can not satisfy the required accuracy of LWAC strength test.In addition,specified compressive strength curves of testing LWAC by rebound method and ultrasonic-rebound combined method are obtained,respectively.

  16. Quantitative evaluation of ultrasonic wave propagation in inhomogeneous anisotropic austenitic welds using 3D ray tracing method. Numerical and experimental validation

    International Nuclear Information System (INIS)

    Austenitic welds and dissimilar welds are extensively used in primary circuit pipes and pressure vessels in nuclear power plants, chemical industries and fossil fuelled power plants because of their high fracture toughness, resistance to corrosion and creep at elevated temperatures. However, cracks may initiate in these weld materials during fabrication process or stress operations in service. Thus, it is very important to evaluate the structural integrity of these materials using highly reliable non-destructive testing (NDT) methods. Ultrasonic non-destructive inspection of austenitic welds and dissimilar weld components is complicated because of anisotropic columnar grain structure leading to beam splitting and beam deflection. Simulation tools play an important role in developing advanced reliable ultrasonic testing (UT) techniques and optimizing experimental parameters for inspection of austenitic welds and dissimilar weld components. The main aim of the thesis is to develop a 3D ray tracing model for quantitative evaluation of ultrasonic wave propagation in an inhomogeneous anisotropic austenitic weld material. Inhomogenity in the anisotropic weld material is represented by discretizing into several homogeneous layers. According to ray tracing model, ultrasonic ray paths are traced during its energy propagation through various discretized layers of the material and at each interface the problem of reflection and transmission is solved. The influence of anisotropy on ultrasonic reflection and transmission behaviour in an anisotropic austenitic weld material are quantitatively analyzed in three dimensions. The ultrasonic beam directivity in columnar grained austenitic steel material is determined three dimensionally using Lamb's reciprocity theorem. The developed ray tracing model evaluates the transducer excited ultrasonic fields accurately by taking into account the directivity of the transducer, divergence of the ray bundle, density of rays and phase

  17. Detection of defect in concrete specimen using ultrasonic wave overlap method

    International Nuclear Information System (INIS)

    The detection of defects in concrete specimens using ultrasonic wave overlap method is studied. Experimental studies are performed to understand the interaction between crack depth, inclusion, and steel bar. In this study, the specimens with surface-opening crack and inclusion were made and tested. The scope of measurement is evaluated through the extension of probing distance. The relationship between crack depth and probing distance estimates that it is effect in case of probing distance less than crack depth. With the results from this study, it is found that the technique using the ultrasonic wave overlap is one of very useful method to evaluate the concrete defect.

  18. Detection of defect in concrete specimen using ultrasonic wave overlap method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yeon Su; Rhim, Hong Chul [Yonsei University, Seoul (Korea, Republic of); Woo, Sang Kyun; Song, Young Chul [Korea Electric Power ResearchInstitue, Daejeon (Korea, Republic of)

    2001-11-15

    The detection of defects in concrete specimens using ultrasonic wave overlap method is studied. Experimental studies are performed to understand the interaction between crack depth, inclusion, and steel bar. In this study, the specimens with surface-opening crack and inclusion were made and tested. The scope of measurement is evaluated through the extension of probing distance. The relationship between crack depth and probing distance estimates that it is effect in case of probing distance less than crack depth. With the results from this study, it is found that the technique using the ultrasonic wave overlap is one of very useful method to evaluate the concrete defect.

  19. Damage analysis for particle reinforced metal matrix composite by ultrasonic method

    Institute of Scientific and Technical Information of China (English)

    YANG Zhi-guo; LONG Shi-guo

    2006-01-01

    The damage characteristic of particle reinforced metal matrix composite (PMMC) was studied by ultrasonic non-destructive evaluation method. After the sample was damaged induced by tensile load,the ultrasonic wave that propagated in the sample were collected. The damage parameter was defined by ultrasonic parameter and the wave signals were analyzed by correlation method. The results show that with the increase of tensile load,the damage parameter increases and the correlation coefficient decreases. The fracture section morphologies of PMMC under tensile load were observed by SEM. It is found that there are many concaves in the metal matrix. Therefore the damage evolution can be concluded. The initial damage is induced by void nucleation,growth and subsequent coalescence in the matrix or interface separation.

  20. A Study on Advanced Ultrasonic Technique for Thermal Fatigue Crack Detection of Thermal Stratification Pipeline in NPPs

    International Nuclear Information System (INIS)

    Ultrasonic inspection techniques are widely used to ensure the reliable operation and lifetime extension of nuclear power plants. Thermal stratification typically occurs in the surge line or the main feed water lines in nuclear power plants. Thermal stratification is a flow condition in which hotter fluid flows over a colder region of fluid in pipeline. Since a change in temperature causes a change in the density of the pipe wall, these thermal conditions might lead to increased overall bending stresses in pipelines. In addition, cyclic changes in stratification height cause thermal stress. This cycling can lead to thermal fatigue crack initiation and crack growth. If thermal fatigue crack grows continuously, the leakage of water or steam will occur and this may cause serious problems on reactor cooling system. Therefore, these cracks must be detected before the crack growth reaches for leakage. In this study, an ultrasonic technique was employed for evaluation of thermal fatigue cracks due to thermal stratification in pipelines of nuclear power plants. The angle beam ultrasonic techniques(time-of-flight diffraction(TOFD) and shadow effect method) were used to detect thermal fatigue cracks which grow from the inner surface of the pipeline. The angle beam ultrasonic technique is usually used for the detection of cracks on the inside of the structures. When ultrasonic waves generated from the angle probe encounters a crack, ultrasonic waves of the shear modes are reflect or transmit from the crack wall. Also ultrasonic waves generated from the angle probe shear modes are diffracted from the tip of the crack, and the shear wave is reflected from the corner of the crack

  1. Grain size evaluation of structural materials in nuclear power plant using a thickness independent ultrasonic method

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiongbing, E-mail: lixb_ex@163.com [CAD/CAM Institute, Central South University, Changsha 410075 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); Song, Yongfeng [CAD/CAM Institute, Central South University, Changsha 410075 (China); Ni, Peijun [The Ningbo Branch of Ordnance Science Institute of China, Ningbo 315103 (China); Wang, Zi; Liu, Feng [State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); Du, Hualong [Mechanical and Aerospace Engineering Department, North Carolina State University, Raleigh, NC 27606 (United States)

    2015-05-15

    Highlights: •We derive a coefficient of ultrasonic attenuation rate related to the grain size. •The mean grain size of the pipe can be evaluated without measuring its thickness. •Experiments show this method is better suited to square pipe than other methods. -- Abstract: It is important to accurately and nondestructively evaluate the grain size of structural materials used in nuclear power plants. The current ultrasonic non-destructive methods are so dependent on the thickness measurement of a square pipe that it reduces their practicality and reliability. In this paper, a novel method using the coefficient of ultrasonic attenuation rate is developed by using the transmission and reflection coefficients. As a result, the mean grain size of the pipe can be nondestructively evaluated without measuring its thickness. Moreover, the signal preprocessing is studied to improve the stability and accuracy of evaluation results. The experimental results show that the dependence of the attenuation rate on grain sizes is much higher than that of the ultrasonic velocity. The relative error of the attenuation rate method is lower than that of the backscatter method if the thickness of the sample is less than 5 mm. When evaluating a TP304 stainless steel square pipe whose thickness is not convenient to measure, the mean grain sizes are measured 103.5 ± 2.6 μm, 96.9 ± 3.5 μm and 94.0 ± 1.7 μm by the attenuation method, the attenuation rate method and the electron backscattering diffraction method, respectively. The result verifies that the presented method works better than the attenuation method due to the fact that the error of the thickness measurement has no effect on the ultrasonic attenuation rate.

  2. Grain size evaluation of structural materials in nuclear power plant using a thickness independent ultrasonic method

    International Nuclear Information System (INIS)

    Highlights: •We derive a coefficient of ultrasonic attenuation rate related to the grain size. •The mean grain size of the pipe can be evaluated without measuring its thickness. •Experiments show this method is better suited to square pipe than other methods. -- Abstract: It is important to accurately and nondestructively evaluate the grain size of structural materials used in nuclear power plants. The current ultrasonic non-destructive methods are so dependent on the thickness measurement of a square pipe that it reduces their practicality and reliability. In this paper, a novel method using the coefficient of ultrasonic attenuation rate is developed by using the transmission and reflection coefficients. As a result, the mean grain size of the pipe can be nondestructively evaluated without measuring its thickness. Moreover, the signal preprocessing is studied to improve the stability and accuracy of evaluation results. The experimental results show that the dependence of the attenuation rate on grain sizes is much higher than that of the ultrasonic velocity. The relative error of the attenuation rate method is lower than that of the backscatter method if the thickness of the sample is less than 5 mm. When evaluating a TP304 stainless steel square pipe whose thickness is not convenient to measure, the mean grain sizes are measured 103.5 ± 2.6 μm, 96.9 ± 3.5 μm and 94.0 ± 1.7 μm by the attenuation method, the attenuation rate method and the electron backscattering diffraction method, respectively. The result verifies that the presented method works better than the attenuation method due to the fact that the error of the thickness measurement has no effect on the ultrasonic attenuation rate

  3. Ultrasonic tests. Pt. 2

    International Nuclear Information System (INIS)

    After a basic treatment of ultrasonic wave propagation, of the state-of-the-art methods and the technical background in the preceeding part, advanced ultrasonic NDT techniques are presented here. The discussion of new development includes - manipulation systems, - automation of ultrasonic testing methods, documentation and evaluation. In the middle of this part the main problem areas will be discussed: - detection of defects (e.g. in coarse grained structures and welds), - classification of defects (e.g. discrimination between crack-like and volumetric faults), - sizing of defects. Research in the field of acoustical holography, development of probes and phased arrays, electromagnetic acoustic transducers and signal enhancement are the main contributing parts to the report. (orig./RW)

  4. A novel actuator phasing method for ultrasonic de-icing of aircraft structures

    Science.gov (United States)

    Borigo, Cody J.

    to facilitate actuator phasing and to advance the state-of-the-art in ultrasonic de-icing technology. These contributions include the development of improved frequency optimization, reduction in the size of the system hardware, and improvements in actuator bonding techniques. It was demonstrated that a dynamic frequency selection method is critical to effectively implementing the actuator phasing method. A miniaturized relay system was also designed and implemented to facilitate actuator phasing in conjunction with a phase splitter circuit and a single amplifier. An improved frequency tuning method was adopted and implemented in the de-icing system to eliminate the need for an impedance analyzer and to provide more accurate frequency selection by directly measuring the forward and reflected power between the amplifier and the de-icing actuators. Overall, it was demonstrated that this novel method can greatly improve the efficiency and effectiveness of the ultrasonic de-icing system by effectively redistributing the shear stress fields at the ice-structure interface, and that this method can be practically implemented in the de-icing system with an overall reduction in size and weight compared to previous versions of the technology.

  5. A method for ultrasonic quality evaluation of glass/polyester composites

    Directory of Open Access Journals (Sweden)

    S. Pawlak

    2007-12-01

    Full Text Available attenuation coefficient and the local fiber content in glass/polyester composites.Design/methodology/approach: Experimental data have been obtained using ultrasonic wave velocity and attenuation measurements. To determine the actual fiber content in the composites, needed to build proper relationships between considered factors, the standard destructive analysis was applied. For ultrasonic non-destructive testing, through-transmission technique was used.Findings: Experimental results have shown that the longitudinal wave velocity increases almost linearly with an increase of the fiber content in the investigated specimens. The second considered parameter of an ultrasonic wave, namely attenuation coefficient was not correlated with the glass content.Research limitations/implications: The propagation velocity of the ultrasonic waves can be affected, apart from fiber content, by interfacial stresses and changes of elastic modulus in polymer matrix during long-lasting service time. These factors overlap and which of the two can affect the ultrasonic wave to a higher degree is yet to established. Further work is needed in this area.Practical implications: The described method can be applied to the post-production quality control of a finished composite product, but in the case of composites made of different constituent materials it is necessary to determine distinct relationships for each composite.Originality/value: The results obtained would be of considerable importance in the industrial applications to achieve a first estimate of fiber content variations in polymer composite materials.

  6. Calibration and validation of ultrasonic reflection methods for thin-film measurement in tribology

    International Nuclear Information System (INIS)

    Interfacial thin liquid films between solid bodies have been measured using ultrasonic reflective techniques in a range of tribological applications such as those present in hydrodynamic bearings, piston rings and mechanical seals (Dwyer-Joyce et al (2004) Tribol. Lett. 17 337–48, Dwyer-Joyce et al (2006) Proc. Instn Mech. Eng. A 220 619–28, Reddyhoff et al (2006) Tribol. Trans. 51 140–49, Harper et al (2005) Tribol. Interface Eng. Ser. 48 305–12). There are two main ultrasonic methods used, the spring model and film resonance techniques. For very thin films (<20 µm) a simple quasi-static spring model has been used to show that the proportion of the wave reflected by the liquid layer depends on the stiffness of the layer. This stiffness can be related to the layer thickness and its material properties. In the film resonance technique the incident ultrasonic wave is used to resonate the liquid layer. The frequency of resonance can then be related to the layer thickness. This paper collates four experiments where oil film thickness is measured by both ultrasonic reflection and an independent method. In the first three experiments the film thickness is measured ultrasonically and this measurement is compared to the thickness inferred from the geometry of the surfaces constraining the liquid film. In the final experiment the ultrasonic results are compared to measurements taken using capacitive and verified laser interferometer techniques. Excellent correlation was observed between the measurement methods in all of the experiments. In particular the film resonance technique showed repeatable and consistent results across a wide range of film thicknesses. The spring model showed a degree of agreement for films above a few microns but this relationship diverged as the film thickness approached the magnitude of the surface roughness. (paper)

  7. Processing surface sizing starch using oxidation, enzymatic hydrolysis and ultrasonic treatment methods--Preparation and application.

    Science.gov (United States)

    Brenner, Tobias; Kiessler, Birgit; Radosta, Sylvia; Arndt, Tiemo

    2016-03-15

    The surface application of starch is a well-established method for increasing paper strength. In surface sizing, a solution of degraded starch is applied to the paper. Two procedures have proved valuable for starch degradation in the paper mill: enzymatic and thermo-oxidative degradation. The objective of this study was to determine achievable efficiencies of cavitation in preparing degraded starch for surface application on paper. It was found that ultrasonic-assisted starch degradation can provide a starch solution that is suitable for surface sizing. The molecular composition of starch solutions prepared by ultrasonic treatment differed from that of starch solutions degraded by enzymes or by thermo-oxidation. Compared to commercial degradation processes, this resulted in intensified film formation and in greater penetration during surface sizing and ultimately in a higher starch content of the paper. Paper sized with ultrasonically treated starch solutions show the same strength properties compared to commercially sized paper.

  8. Analysis of ultrasound propagation in a steel pipe using ultrasonic pulse doppler method

    International Nuclear Information System (INIS)

    Thermal powers of nuclear reactors are calculated by the enthalpy difference between reactor feed water and main steam. Improvement of the measurement accuracy in the flow rate measurements of reactor feed water enables us to uprate reactor thermal power, called MUR (Measurement Uncertainly Recapture) uprate. The ultrasonic pulse Doppler system is expected to be a suitable method featuring the capability of measuring the flow profile directly in a pipe. For the optimum measurements, ultrasonic path from ultrasonic transducer into the fluid through steel pipe wall should be carefully predicted in high temperature water. This paper presents analytical results of ultrasound propagation using FEM simulation code and experimental results of pipe flow rate at high temperature thermal conditions. (author)

  9. The two coupling fluids method for ultrasonic velocity measurement. Application to biological tissues

    International Nuclear Information System (INIS)

    Measuring the ultrasonic velocity in soft materials, especially in biological tissues, is never easy. One of the main issues is that the thickness of the sample under test is badly defined. From the time-of-flight measurement method, uncertainties in the thickness induce important uncertainties in experimental results. This implies that the ultrasonic velocity is often a poor criterion when it could be a good one. This paper introduces a new method to measure the ultrasonic velocity in soft materials without knowing the sample thickness The main idea of this method is to use two different coupling media to make two relative time-of-flight measurements. The comparison of these two measurements gives the ultrasonic velocity in the sample under test. Furthermore, this comparison can give the local thickness of the sample. The uncertainty calculations show that the effect on the thickness is drastically reduced by using this new ultrasound method. This method is validated on a reference sample (silicone). Before conclusion, some experimental results obtained with mouse skin samples are presented

  10. Liquid film thickness measurement in small square pipe using ultrasonic pulse-echo method

    International Nuclear Information System (INIS)

    The ultrasonic pulse-echo method is applied to measure thickness in a liquid film. To prevent a piezoelectric element cracking under high temperature conditions, the maximum frequency of sound is limited. On the other hand, the required thickness resolution is about 0.05mm to detect whether or not dryout has occurred. An ultrasonic transducer frequency of 5MHz is selected to satisfy both frequency and resolution requirements for air-water experiments. The changing liquid film thickness on a stainless steel plate is simultaneously measured with the ultrasonic transducer and a laser displacement sensor. The two types of results show good agreement within the range from 0.06 to 0.22mm. Next, the air-water annular flow in the small vertical square pipe is measured using the pulse-echo method. A liquid film sensor based on the electrical conductance method is also used for results comparison. The most frequently observed thickness measured by the two methods is almost the same based on comparison of the measurement histograms. To estimate the resolution of the pulse-echo method, the pulse intensities of multiple reflections in the liquid film are simulated. The results show that a liquid film thickness of 0.03mm can be measured even if the ultrasonic frequency is less than 5MHz. (author)

  11. Advanced methods of fatigue assessment

    CERN Document Server

    Radaj, Dieter

    2013-01-01

    The book in hand presents advanced methods of brittle fracture and fatigue assessment. The Neuber concept of fictitious notch rounding is enhanced with regard to theory and application. The stress intensity factor concept for cracks is extended to pointed and rounded corner notches as well as to locally elastic-plastic material behaviour. The averaged strain energy density within a circular sector volume around the notch tip is shown to be suitable for strength-assessments. Finally, the various implications of cyclic plasticity on fatigue crack growth are explained with emphasis being laid on the DJ-integral approach.   This book continues the expositions of the authors’ well known reference work in German language ‘Ermüdungsfestigkeit – Grundlagen für Ingenieure’ (Fatigue strength – fundamentals for engineers).

  12. New junction method of plastic by ultrasonic wave; Choonpa ni yoru plastic no shinsetsugoho

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, S. [Shibaura Institute of Technology, Tokyo (Japan). Faculty of Engineering

    1996-05-01

    This paper describes three types of new junction methods for plastic in which ultrasonic energy is used. The node junction method by longitudinal vibration is based on the feature that the heat generation by ultrasonic energy is high in the node of amplitude distribution by vibration of a joined object. An impedance matching section is set among the tool, joined object, and jig, and the junction place is set in the node position of amplitude by longitudinal vibration to improve the efficiency. For the junction of a vessel cover, the power and operation efficiencies were improved. The junction method by torsional vibration uses torsional vibration instead of longitudinal vibration. The manufactured device has the characteristics that the sound output is 40 W when the vibration rate of a torsional vibrator is 1.61 m/s. In this case, the electric sound exchange efficiency is 92% at maximum. The junction of a tetrafluoroethylene sheet that is difficult in a longitudinal vibration system was tried as a preliminary experiment. As a result, the information on junction was obtained. In the junction method by a focusing ultrasonic wave, ultrasonic energy of several megahertzs is focused for junction. A PZT electrostrictive spherical vibrator is used. Junction is carried out in the focal area. The junction strength increases. 1 ref., 5 figs.

  13. A Novel Ultrasonic Method for Characterizing Microstructural Gradients in Tubular Structures

    Science.gov (United States)

    Roth, Don J.; Carney, Dorothy V.; Baaklini, George Y.; Bodis, James R.; Rauser, Richard W.

    1998-01-01

    Ultrasonic velocity and time-of-flight (TOF) imaging that uses back surface reflections to gage volumetric material quality is highly suited for quantitative characterization of microstructural gradients including those due to pore fraction, density, fiber fraction, and chemical composition variations. However, a weakness of conventional pulse echo ultrasonic velocity and TOF imaging is that the image shows the effects of thickness as well as microstructural variations, unless the part is uniformly thick. This limits this imaging method's usefulness in practical applications. Prior studies have described a pulse echo TOF based ultrasonic imaging method that requires using a single transducer in combination with a reflector plate placed behind samples which, eliminates the effect of thickness variation in the image. In those studies, this method was successful at isolating ultrasonic variations due to material in plate like samples of silicon nitride, metal matrix composite, and polymer matrix composite. In this study, the method is engineered for inspection of more complex shaped structures- those having (hollow) tubular or curved geometry. The experimental inspection technique and results are described as applied to a polymer matrix composite "proof of concept" tube that contains machined patches of various depths and an as manufactured monolithic silicon nitride ceramic tube that might be used in "real world" applications.

  14. Application of wavelet filtering and Barker-coded pulse compression hybrid method to air-coupled ultrasonic testing

    Science.gov (United States)

    Zhou, Zhenggan; Ma, Baoquan; Jiang, Jingtao; Yu, Guang; Liu, Kui; Zhang, Dongmei; Liu, Weiping

    2014-10-01

    Air-coupled ultrasonic testing (ACUT) technique has been viewed as a viable solution in defect detection of advanced composites used in aerospace and aviation industries. However, the giant mismatch of acoustic impedance in air-solid interface makes the transmission efficiency of ultrasound low, and leads to poor signal-to-noise (SNR) ratio of received signal. The utilisation of signal-processing techniques in non-destructive testing is highly appreciated. This paper presents a wavelet filtering and phase-coded pulse compression hybrid method to improve the SNR and output power of received signal. The wavelet transform is utilised to filter insignificant components from noisy ultrasonic signal, and pulse compression process is used to improve the power of correlated signal based on cross-correction algorithm. For the purpose of reasonable parameter selection, different families of wavelets (Daubechies, Symlet and Coiflet) and decomposition level in discrete wavelet transform are analysed, different Barker codes (5-13 bits) are also analysed to acquire higher main-to-side lobe ratio. The performance of the hybrid method was verified in a honeycomb composite sample. Experimental results demonstrated that the proposed method is very efficient in improving the SNR and signal strength. The applicability of the proposed method seems to be a very promising tool to evaluate the integrity of high ultrasound attenuation composite materials using the ACUT.

  15. Modern ultrasonic flowmeters

    Science.gov (United States)

    Gurevich, V. M.; Truman, S. G.

    1986-01-01

    The current status of ultrasonic flowmeters were reviewed on the basis of materials published in the Soviet Union and elsewhere. The following advantages of ultrasonic flowmeters over earlier instruments are cited. A comparative analysis is made of the design methods employed in ultrasonic flowmeters. The evolution of ultrasonic flowmetering is traced from the first generation and trends in their development are analyzed.

  16. [Measurement method of arterial shear stress of rats model based on ultrasonic particle imaging velocimetry].

    Science.gov (United States)

    Xhu, Yiheng; Qian, Ming; Niu, Lili; Zheng, Hairong; Lu, Guangwen

    2014-12-01

    The development and progression of atherosclerosis and thrombosis are closely related to changes of hemodynamics parameters. Ultrasonic pulse wave Doppler technique is normally used for noninvasively blood flow imaging. However, this technique only provides one-dimensional velocity and depends on the angle between the ultrasound beam and the local velocity vector. In this study, ultrasonic particle image velocimetry method was used to assess whole field hemodynamic changes in normal blood vessels. By using the polynomial fitting method, we investigated the velocity gradient and assessed the shear in different blood flow velocity of 10 healthy rats. It was found that using four polynomial fitting could result in optimal measurement results. The results obtained by ultrasonic particle image velocimetry accorded with the results obtained using Doppler technique. The statistical average of cyclical vessel wall shear stress was positively related to the locational mean velocity. It is proven that ultrasonic particle image velocimetry method could be used to assess directly the real-time whole field hemodynamic changes in blood vessels and was non-invasively, and should be a good prosperous technique for monitoring complex blood flow in stenotic ar- teries.

  17. Characterization of Olive Oil by Ultrasonic and Physico-chemical Methods

    Science.gov (United States)

    Alouache, B.; Khechena, F. K.; Lecheb, F.; Boutkedjirt, T.

    Olive oil excels by its nutritional and medicinal benefits. It can be consumed without any treatment. However, its quality can be altered by inadequate storage conditions or if it is mixed with other kinds of oils. The objective of this work is to demonstrate the ability of ultrasonic methods to characterize and control olive oil quality. By using of a transducer of 2.25 MHz nominal frequency, in pulse echo mode, ultrasonic parameters, such as propagation velocity and attenuation,have been measured for pure olive oil and for its mixtures with sunflower oil at different proportions. Mechanical properties, such as density and viscosity, have also been determined. The results of ultrasonic measurements are consistent with those obtained by physico-chemical methods, such as rancidity degree, acid index, UV specific extinction coefficient and viscosity. They show that the ultrasonic method allows to distinguish between mixtures at different proportions. The study allows concluding that ultrasound techniques can be considered as a useful complement to existing physico-chemical analysis techniques.

  18. Study of a method for the defect detection by ultrasonic's technic: Prony's method, theory and practice

    International Nuclear Information System (INIS)

    The goal of PRONY's method is to identify a sampling of N signal's values with a finite linear development of p complex exponentials. This work has been done to use this method for the identification of a signal obtained by ''insonification'' (i.e. by interacting with an ultrasonic impulsion) of a target. The identified complex exponentials give the constitutive amplitudes, dampings, frequencies and phases of the signal, these values characterize geometry and size of unknown targets. Mathematics involve that the solution of 3D-elastodynamic equations is given asymptotically in time by an infinite summation of complex exponentials. The signal obtained by ''insonification'' is characteristic of this solution: it means that PRONY's method can be well suited for this identification. For that it was necessary to understand this method in all its aspects. Consequently in paragraph 1 we expose its principle and algorithm. We prove, it is one of its advantage, that PRONY's is an interpolation method if N = 2p. If N > 2p the method is working like a least square method. We study, at the paragraph 2, how the two essentials parameters N and p of the method interact one with the other. The influence of the noise is observed, knowing that a complete study of it will need some developments out of this presentation. And then we approach, in the paragraph 3, the practice of the method, in order to verify its quality for identified tests problems. Successively we analyze a damping signal, an electric signal with damping, a pure periodic signal. The behaviour of PRONY's is excellent with a few precautions that we specify. Finally we are interested with a ''realistic'' seismic signal. The ultrasonic wave iteration with defect is then observed in paragraph 4. Physical and experimental device are briefly described. The identification's problem of a target, in practice the identification of a defect, is still widely opened if we use PRONY. Is it necessary to give up. Certainly not, the

  19. Advanced Recording and Preprocessing of Physiological Signals. [data processing equipment for flow measurement of blood flow by ultrasonics

    Science.gov (United States)

    Bentley, P. B.

    1975-01-01

    The measurement of the volume flow-rate of blood in an artery or vein requires both an estimate of the flow velocity and its spatial distribution and the corresponding cross-sectional area. Transcutaneous measurements of these parameters can be performed using ultrasonic techniques that are analogous to the measurement of moving objects by use of a radar. Modern digital data recording and preprocessing methods were applied to the measurement of blood-flow velocity by means of the CW Doppler ultrasonic technique. Only the average flow velocity was measured and no distribution or size information was obtained. Evaluations of current flowmeter design and performance, ultrasonic transducer fabrication methods, and other related items are given. The main thrust was the development of effective data-handling and processing methods by application of modern digital techniques. The evaluation resulted in useful improvements in both the flowmeter instrumentation and the ultrasonic transducers. Effective digital processing algorithms that provided enhanced blood-flow measurement accuracy and sensitivity were developed. Block diagrams illustrative of the equipment setup are included.

  20. A new deconvolution method applied to ultrasonic images; Etude d'une methode de deconvolution adaptee aux images ultrasonores

    Energy Technology Data Exchange (ETDEWEB)

    Sallard, J

    1999-07-01

    This dissertation presents the development of a new method for restoration of ultrasonic signals. Our goal is to remove the perturbations induced by the ultrasonic probe and to help to characterize the defects due to a strong local discontinuity of the acoustic impedance. The point of view adopted consists in taking into account the physical properties in the signal processing to develop an algorithm which gives good results even on experimental data. The received ultrasonic signal is modeled as a convolution between a function that represents the waveform emitted by the transducer and a function that is abusively called the 'defect impulse response'. It is established that, in numerous cases, the ultrasonic signal can be expressed as a sum of weighted, phase-shifted replicas of a reference signal. Deconvolution is an ill-posed problem. A priori information must be taken into account to solve the problem. The a priori information translates the physical properties of the ultrasonic signals. The defect impulse response is modeled as a Double-Bernoulli-Gaussian sequence. Deconvolution becomes the problem of detection of the optimal Bernoulli sequence and estimation of the associated complex amplitudes. Optimal parameters of the sequence are those which maximize a likelihood function. We develop a new estimation procedure based on an optimization process. An adapted initialization procedure and an iterative algorithm enables to quickly process a huge number of data. Many experimental ultrasonic data that reflect usual control configurations have been processed and the results demonstrate the robustness of the method. Our algorithm enables not only to remove the waveform emitted by the transducer but also to estimate the phase. This parameter is useful for defect characterization. At last the algorithm makes easier data interpretation by concentrating information. So automatic characterization should be possible in the future. (author)

  1. Analytical Method for Reduction of Residual Stress Using Low Frequency and Ultrasonic Vibrations

    Science.gov (United States)

    Aoki, Shigeru; Kurita, Katsumi; Koshimizu, Shigeomi; Nishimura, Tadashi; Hiroi, Tetsumaro; Hirai, Seiji

    Welding is widely used for construction of many structures. It is well known that residual stress is generated near the bead because of locally given heat. Tensile residual stress on the surface degrades fatigue strength. On the other hand, welding is used for repair of mold and die. In this case, reduction of residual stress is required because of protection from crack of welded part in mold and die. In this paper, a new method for reduction of residual stress of welded joint is proposed for repair welding of mold and die. In this method, low frequency and ultrasonic vibrations are used during welding. Thick plates are used as specimens of mold and die. Residual stresses are reduced when low frequency and ultrasonic vibrations are used during welding. Experimental results are examined by simulation method using an analytical model. One mass model considering plastic deformation is used as an analytical model. Experimental results are demonstrated by simulation method.

  2. Advanced median method for timing jitter compensation

    Institute of Scientific and Technical Information of China (English)

    Wang Chen; Zhu Jiangmiao; Jan Verspecht; Liu Mingliang; Li Yang

    2008-01-01

    Timing jitter is one of the main factors that influence on the accuracy of time domain precision measurement. Timing jitter compensation is one of the problems people concern. Because of the flaws of median method, PDF deconvolution method and synthetic method, we put forward a new method for timing jitter compensation, which is called advanced median method. The theory of the advanced median method based on probability and statistics is analyzed, and the process of the advanced median method is summarized in this paper. Simulation and experiment show that compared with other methods, the new method could compensate timing jitter effectively.

  3. Compressive strength evaluation of structural lightweight concrete by non-destructive ultrasonic pulse velocity method.

    Science.gov (United States)

    Bogas, J Alexandre; Gomes, M Glória; Gomes, Augusto

    2013-07-01

    In this paper the compressive strength of a wide range of structural lightweight aggregate concrete mixes is evaluated by the non-destructive ultrasonic pulse velocity method. This study involves about 84 different compositions tested between 3 and 180 days for compressive strengths ranging from about 30 to 80 MPa. The influence of several factors on the relation between the ultrasonic pulse velocity and compressive strength is examined. These factors include the cement type and content, amount of water, type of admixture, initial wetting conditions, type and volume of aggregate and the partial replacement of normal weight coarse and fine aggregates by lightweight aggregates. It is found that lightweight and normal weight concretes are affected differently by mix design parameters. In addition, the prediction of the concrete's compressive strength by means of the non-destructive ultrasonic pulse velocity test is studied. Based on the dependence of the ultrasonic pulse velocity on the density and elasticity of concrete, a simplified expression is proposed to estimate the compressive strength, regardless the type of concrete and its composition. More than 200 results for different types of aggregates and concrete compositions were analyzed and high correlation coefficients were obtained. PMID:23351273

  4. A Curve-fitting Calibration Method applied for Ultrasonic Flow-meter

    OpenAIRE

    Yong Luo; Rangding Wang; Ling Yao

    2013-01-01

    As the influence of fluid distribution in the internal pipe, the measurement characteristics of theory and practice exist significant differences in Ultrasonic Flow-meter(USF). Through analysis of fluid state, the method of curve-fitting is applied for the calibration of USF. Experimental results show that the USF can achieve level-1 accuracy with just a correction of 5 flow points, and this method performs a low computational complexity and strong practicality.  

  5. A Curve-fitting Calibration Method applied for Ultrasonic Flow-meter

    Directory of Open Access Journals (Sweden)

    Yong Luo

    2013-10-01

    Full Text Available As the influence of fluid distribution in the internal pipe, the measurement characteristics of theory and practice exist significant differences in Ultrasonic Flow-meter(USF. Through analysis of fluid state, the method of curve-fitting is applied for the calibration of USF. Experimental results show that the USF can achieve level-1 accuracy with just a correction of 5 flow points, and this method performs a low computational complexity and strong practicality.  

  6. Use of ultrasonic array method for positioning multiple partial discharge sources in transformer oil.

    Science.gov (United States)

    Xie, Qing; Tao, Junhan; Wang, Yongqiang; Geng, Jianghai; Cheng, Shuyi; Lü, Fangcheng

    2014-08-01

    Fast and accurate positioning of partial discharge (PD) sources in transformer oil is very important for the safe, stable operation of power systems because it allows timely elimination of insulation faults. There is usually more than one PD source once an insulation fault occurs in the transformer oil. This study, which has both theoretical and practical significance, proposes a method of identifying multiple PD sources in the transformer oil. The method combines the two-sided correlation transformation algorithm in the broadband signal focusing and the modified Gerschgorin disk estimator. The method of classification of multiple signals is used to determine the directions of arrival of signals from multiple PD sources. The ultrasonic array positioning method is based on the multi-platform direction finding and the global optimization searching. Both the 4 × 4 square planar ultrasonic sensor array and the ultrasonic array detection platform are built to test the method of identifying and positioning multiple PD sources. The obtained results verify the validity and the engineering practicability of this method.

  7. High pressure changes of the castor oil viscosity by ultrasonic method

    Science.gov (United States)

    Rostocki, A. J.; Siegoczyński, R. M.; Kielczyński, P.; Szalewski, M.

    2008-07-01

    The pressure change of viscosity of castor oil have been measured by ultrasonic method within the range of pressure up to 0.9 GPa. For the measurement, the authors have applied a new ultrasonic method based on Bleustein-Gulyaev (B-G) waves. For the lower pressures (up to 0.3 GPa) the results have been compared with earlier results obtained by falling body method, whereas for the higher pressure range results were compared with those obtained by the flow type viscometer. The measurements have shown: 1. Exponential rise of viscosity with pressure up to 0.4 GPa according to the Barus formula. 2. Extraordinary increment of viscosity at constant pressure during phase transition. 3. The decomposition of the high pressure phase during the decompression process have shown very large hysteresis of viscosity on pressure. 4. After the decompression process the viscosity lasts higher then a initial value for several hours.

  8. Chromium containing silica: effect of ultrasonic and purification methods on color products

    International Nuclear Information System (INIS)

    Chromium containing silica has numerous applications, such as: fiber-optics, luminescent materials, catalysts and pigments. In paint and ceramic pigments, chromate and dichromate ions, and silica are largely used. In this paper, it has been investigated the effect of pH, heating methods, and ultrasonic stirring on chromium oxidation states coprecipitated with silica. The material has been obtained from the coprecipitation of an aqueous diluted sodium silicate solution and acid chromium nitrate solution, purified by extractions and dialysis, and dried with microwave oven. Products have been characterized by X-ray powder diffraction, infrared vibrational spectroscopy and nitrogem adsorption isotherm (BET). Coprecipitates are non cristalline and the specific surface area value for sample obtained by conventional heating is smaller than the one for sample obtained by ultrasonic method. It is possible to obtain silica with different colors from blue due to the Cr(III), to yellow due to the Cr (VI), depending on the precipitation, purification and drying methods. (author)

  9. Nondestructive Testing and Characterization of Residual Stress Field Using an Ultrasonic Method

    Institute of Scientific and Technical Information of China (English)

    SONG Wentao; XU Chunguang; PAN Qinxue; SONG Jianfeng

    2016-01-01

    To address the difficulty in testing and calibrating the stress gradient in the depth direction of mechanical components, a new technology of nondestructive testing and characterization of the residual stress gradient field by ultrasonic method is proposed based on acoustoelasticity theory. By carrying out theoretical analysis, the sensitivity coefficients of different types of ultrasonic are obtained by taking the low carbon steel(12%C) as a research object. By fixing the interval distance between sending and receiving transducers, the mathematical expressions of the change of stress and the variation of time are established. To design one sending-one receiving and oblique incidence ultrasonic detection probes, according to Snell law, the critically refracted longitudinal wave (LCR wave) is excited at a certain depth of the fixed distance of the tested components. Then, the relationship between the depth of LCR wave detection and the center frequency of the probe in Q235 steel is obtained through experimental study. To detect the stress gradient in the depth direction, a stress gradient LCR wave detection model is established, through which the stress gradient formula is derived by the relationship between center frequency and detecting depth. A C-shaped stress specimen of Q235 steel is designedto conduct stress loading tests, and the stress is measured with the five group probes at different center frequencies. The accuracy of ultrasonic testing is verified by X-ray stress analyzer. The stress value of each specific depth is calculated using the stress gradient formula. Accordingly, the ultrasonic characterization of residual stress field is realized. Characterization results show that the stress gradient distribution is consistent with the simulation in ANSYS. The new technology can be widely applied in the detection of the residual stress gradient field caused by mechanical processing, such as welding and shot peening.

  10. Nondestructive testing and characterization of residual stress field using an ultrasonic method

    Science.gov (United States)

    Song, Wentao; Xu, Chunguang; Pan, Qinxue; Song, Jianfeng

    2016-03-01

    To address the difficulty in testing and calibrating the stress gradient in the depth direction of mechanical components, a new technology of nondestructive testing and characterization of the residual stress gradient field by ultrasonic method is proposed based on acoustoelasticity theory. By carrying out theoretical analysis, the sensitivity coefficients of different types of ultrasonic are obtained by taking the low carbon steel(12%C) as a research object. By fixing the interval distance between sending and receiving transducers, the mathematical expressions of the change of stress and the variation of time are established. To design one sending-one receiving and oblique incidence ultrasonic detection probes, according to Snell law, the critically refracted longitudinal wave (LCR wave) is excited at a certain depth of the fixed distance of the tested components. Then, the relationship between the depth of LCR wave detection and the center frequency of the probe in Q235 steel is obtained through experimental study. To detect the stress gradient in the depth direction, a stress gradient LCR wave detection model is established, through which the stress gradient formula is derived by the relationship between center frequency and detecting depth. A C-shaped stress specimen of Q235 steel is designed to conduct stress loading tests, and the stress is measured with the five group probes at different center frequencies. The accuracy of ultrasonic testing is verified by X-ray stress analyzer. The stress value of each specific depth is calculated using the stress gradient formula. Accordingly, the ultrasonic characterization of residual stress field is realized. Characterization results show that the stress gradient distribution is consistent with the simulation in ANSYS. The new technology can be widely applied in the detection of the residual stress gradient field caused by mechanical processing, such as welding and shot peening.

  11. Effect of low-frequency ultrasound on flow rate measurements using the ultrasonic velocity profile method

    International Nuclear Information System (INIS)

    This study presents a low-frequency ultrasonic propagation analysis using the finite-element method (FEM). Experimental results of flow rate measurements using the ultrasonic velocity profile (UVP) method are also presented. The ultrasound frequency, pipe diameter, and pipe wall thickness are 0.274 MHz, 590.6 mm, and 9.5 mm, respectively. Six waves are generated per ultrasound pulse. To analyze the entire pipe region, the FEM is combined with the Kirchhoff method. The experiments of flow rate measurements are conducted using the high Reynolds number calibration facility at the National Metrology Institute of Japan. The range of the Reynolds number is from 4.4×106 to 1.7×107. Wide spreading of the ultrasonic beam in the axial direction of the pipe is observed because of multiple reflections in the pipe wall. This wide beam affects the measured velocity profile, particularly in the region near the pipe wall. In addition, the flow rate errors are approximately 10% (deviating by 1.1%) across the investigated range of Reynolds number. This result suggests that the experimental flow rate errors might be used as correction factors of flow rate measurements using the UVP method. (author)

  12. Characterization and comparison of defects detection limits of three ultrasonic non destructive methods

    Directory of Open Access Journals (Sweden)

    Welemane H.

    2010-06-01

    Full Text Available This work deals with the Liquid Resin Infusion (LRI process developed within the research program “FUSelage COMPosite” of DAHER SOCATA. This manufacturing process enables the realization of complex composite structures or fuselage elements in a single phase (mono-material, which considerably reduce connections and relative difficulties. The concern here is the investigation of non destructive testing (NDT methods that can be applied to LRI-structures in order to define their capacities for defect detection, and especially their associated critical defect size. In aviation industry, the AITM standards require the ultrasonic testing as NDT for composite materials. Therefore the aim of this work is to characterize and compare three different and complementary ultrasonic techniques on composite specimens. Such analysis allows to define the NDT application field of each method in term of defect detection.

  13. Ultrasonic imaging methods for quality evaluation of the CANDU fuel bundle welds

    International Nuclear Information System (INIS)

    For more than 20 years, the quality control of the end-cap/end-plates welds and of the brazed appendage joints is made by destructive methods (metallographic examinations or mechanical tests) on specimens sampled from production. Having a very limited statistics, these destructive methods are useful only to indicate 'trends' of the production quality, not for detecting infrequent single defect events. It is recognized that nondestructive examination techniques are required to achieve sufficient 'visibility' of the production quality, at a statistically significant sampling rate. For this reason, the INR-Ultra-acoustics R and D has developed the MICROSCAN equipment family for high resolution ultrasonic imaging, with performances close to the Acoustic Microscopy domain. The paper makes a presentation of the performances of the MICROSCAN 02/03 equipment for B and C-scan high-frequency ultrasonic imaging. Experimental results are presented and comparisons are make with metallographic examinations. (Author) 8 Figs., 4 Refs

  14. An automated data processing method dedicated to 3D ultrasonic non destructive testing of composite pieces

    International Nuclear Information System (INIS)

    State-of the art Non Destructive Testing using ultrasound is based on evaluation of C-scan images, which is done mainly visually. The development of the new Sampling Phased Array technique SPA by IZFP Fraunhofer provides a fast three-dimensional reconstruction of inner object structures. This new inspection technique is to be complemented with fully or semi-automated evaluation of ultrasonic data, providing maximum support to the operator. We present in this contribution a processing method for SPA ultrasonic data, where the main focus of this paper will be on speckle noise reduction. The evaluation method is applied on carbon fibre composite where it demonstrates robust and successful performance in recognition of defects.

  15. RAPID AND NONDESTRUCTIVE MEASUREMENT SYSTEM FOR WELDING RESDIUAL STRESS BY ULTRASONIC METHOD

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Traditional methods of residual stress measurement are generally destructive or semi-destructive, as well as expensive, time-consuming and complex to implement. With the new development of welded structure, traditional methods can not satisfy the need of full life task management. So the acoustical theory is introduced, since the ultrasonic technique provides a useful nondestructive tool in the evaluation of stresses. In this study an ultrasonic stress measurement experimental installation is established, which consists of a special transducer, a signal emission unit and a signal recipient processing unit. Longitudinal critically refracted wave is selected as the measurement wave mode. The supporting software is programmed by Labview software. The longitudinal residual stress and transverse residual stress of twin wire welded plate are measured by this installment, in which the measuring process is real-time, quick and nondestructive. The experiment results indicate that the system can satisfy the need of life evaluation for welded structure. The system is light and portable.

  16. Production of biodiesel from lipid of phytoplankton Chaetoceros calcitrans through ultrasonic method.

    Science.gov (United States)

    Kwangdinata, Raymond; Raya, Indah; Zakir, Muhammad

    2014-01-01

    A research on production of biodiesel from lipid of phytoplankton Chaetoceros calcitrans through ultrasonic method has been done. In this research, we carried out a series of phytoplankton cultures to determine the optimum time of growth and biodiesel synthesis process from phytoplankton lipids. Process of biodiesel synthesis consists of two steps, that is, isolation of phytoplankton lipids and biodiesel synthesis from those lipids. Oil isolation process was carried out by ultrasonic extraction method using ethanol 96%, while biodiesel synthesis was carried out by transesterification reaction using methanol and KOH catalyst under sonication. Weight of biodiesel yield per biomass Chaetoceros calcitrans is 35.35%. Characterization of biodiesel was well carried out in terms of physical properties which are density and viscosity and chemical properties which are FFA content, saponification value, and iodine value. These values meet the American Society for Testing and Materials (ASTM D6751) standard levels, except for the viscosity value which was 1.14 g · cm(-3).

  17. Advanced ultrasonic inspection system for the ID-inspection of reactor pressure vessels of BWRs

    International Nuclear Information System (INIS)

    A newly-developed, modular ultrasonic examination system has been developed by Siemens for the ID inspection of BWR RPV'S. It is based on the phased-array technique with hybrid probes using the latest in manipulator and control equipment technology to allow the often hard-to-access weld areas of older reactor pressure vessels in US BWR plants to be examined within a very short time and with minimal radiation exposure of the examination personnel. New NRC stipulations requiring almost complete ultrasonic examination of all RPV welds can be fully satisfied using this system for the ID inspection of all longitudinal and circumferential welds above the jet pump baffle plate

  18. Ultrasonic mammography

    International Nuclear Information System (INIS)

    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)

  19. Structural health monitoring of a railway truss bridge using vibration-based and ultrasonic methods

    International Nuclear Information System (INIS)

    This paper presents results of in situ investigation of a railway truss bridge in the context of structural health monitoring (SHM). Three experimental methods are examined. Dynamic responses of the bridge recorded by strain gauges are confronted with alternative ways of acquisition using piezoelectric patch sensors and ultrasonic probeheads. All types of sensors produce similar output. Also the corresponding responses of the numerical model of the bridge match experimental data

  20. Preparation of Al/Si functionally graded materials using ultrasonic separation method

    OpenAIRE

    Zhang Zhongtao; Li Tingju; Yue Hongyun

    2008-01-01

    Functionally graded materials (FGM) have been widely used in many industries such as aerospace, energy and electronics. In this experimental study of fabricating FGM, an approach was developed to prepare Al/Si FGM using power ultrasonic separation method. Material sample with continuously changing composition and performance/properties was successfully produced. Results showed that the microstructure of the FGM sample transited, from its top to bottom, from the hypereutectic structure with a ...

  1. A new ultrasonic method to detect chemical additives in branded milk

    Indian Academy of Sciences (India)

    S Mohanan; P G Thomas Panicker; Lilly Iype; M Laila; I Domini; R G Bindu

    2002-09-01

    A new ultrasonic method – thermoacoustic analysis – is reported for the detection of the added chemical preservatives in branded milk. The nature of variation and shift in the thermal response of the acoustic parameters specific acoustic impedance, adiabatic compressibility and Rao’s specific sound velocity for different samples of branded milk as compared to the chemical added pure milk are explained as due to the presence of chemicals in these branded samples.

  2. A Digital Method for the Detection of Blood Flow Direction in Ultrasonic Doppler Systems

    OpenAIRE

    P. Acevedo–Contla.; M. Barragán–Ocampo.; E. Moreno–Hernández.; F. García–Nocetti.; M. Fuentes–Cruz.; A. Sotomayor–Ortega

    2010-01-01

    Doppler ultrasound systems are widely used to study blood flow and diagnosis of vascular diseases. An important characteristic of these systems is the ability to detect the direction of the blood flow. Most Doppler ultrasound systems apply a quadrature demodulation technique on the ultrasonic transducer output signal. Therefore additional treatment is necessary to separate forward and reverse flow signals. This work presents a digital method to convert signals in quadrature into directional s...

  3. A method for the measurement of hydrodynamic oil films using ultrasonic reflection

    OpenAIRE

    Dwyer-Joyce, R.S.; Harper, P; Drinkwater, B. W.

    2004-01-01

    The measurement of the thickness of an oil film in a lubricated component is essential information for performance monitoring and control. In this work, a new method for oil film thickness measurement, based on the reflection of ultrasound, is evaluated for use in fluid film journal bearing applications. An ultrasonic wave will be partially reflected when it strikes a thin layer between two solid media. The proportion of the wave reflected depends on the thickness of the layer and its acousti...

  4. Ultrasonic Guided Wave Method For Crack Detection In Buried Plastic Pipe

    Directory of Open Access Journals (Sweden)

    Wan Hamat Wan Sofian

    2016-01-01

    Full Text Available Plastic pipe are widely used in many fields for the fluid or gaseous product conveyance but basic components of a plastic material made it very sensitive to damage, which requires techniques for detecting damage reliable and efficient. Ultrasonic guided wave is a sensitive method based on propagation of low-frequency excitation in solid structures for damage detection. Ultrasonic guided wave method are performed to investigate the effect of crack to the frequency signal using Fast Fourier Transform (FFT analysis. This paper researched to determine performance of ultrasonic guided wave method in order to detect crack in buried pipeline. It was found that for an uncrack pipe, FFT analysis shows one peak which is the operating frequency by the piezoelectric actuator itself while the FFT analysis for single cracked pipe shows two peak which is the operating frequency by the piezoelectric actuator itself and the resultant frequency from the crack. For multi cracked pipe, the frequency signal shows more than two peak depend the number of crack. The results presented here may facilitate improvements in the accuracy and precision of pipeline crack detection.

  5. Analysis of ultrasonically rotating droplet using moving particle semi-implicit and distributed point source methods

    Science.gov (United States)

    Wada, Yuji; Yuge, Kohei; Tanaka, Hiroki; Nakamura, Kentaro

    2016-07-01

    Numerical analysis of the rotation of an ultrasonically levitated droplet with a free surface boundary is discussed. The ultrasonically levitated droplet is often reported to rotate owing to the surface tangential component of acoustic radiation force. To observe the torque from an acoustic wave and clarify the mechanism underlying the phenomena, it is effective to take advantage of numerical simulation using the distributed point source method (DPSM) and moving particle semi-implicit (MPS) method, both of which do not require a calculation grid or mesh. In this paper, the numerical treatment of the viscoacoustic torque, which emerges from the viscous boundary layer and governs the acoustical droplet rotation, is discussed. The Reynolds stress traction force is calculated from the DPSM result using the idea of effective normal particle velocity through the boundary layer and input to the MPS surface particles. A droplet levitated in an acoustic chamber is simulated using the proposed calculation method. The droplet is vertically supported by a plane standing wave from an ultrasonic driver and subjected to a rotating sound field excited by two acoustic sources on the side wall with different phases. The rotation of the droplet is successfully reproduced numerically and its acceleration is discussed and compared with those in the literature.

  6. System and method for the mitigation of paraffin wax deposition from crude oil by using ultrasonic waves

    Science.gov (United States)

    Towler, Brian F.

    2007-09-04

    A method for mitigating the deposition of wax on production tubing walls. The method comprises positioning at least one ultrasonic frequency generating device adjacent the production tubing walls and producing at least one ultrasonic frequency thereby disintegrating the wax and inhibiting the wax from attaching to the production tubing walls. A system for mitigating the deposition of wax on production tubing walls is also provided.

  7. Fabrication and characterization of hydroxyapatite microspheres obtained by ultrasonic atomization method

    Institute of Scientific and Technical Information of China (English)

    WANG Aijuan; LU Yupeng; CHEN Chuanzhong; SUN Ruixue

    2007-01-01

    Two kinds of hydroxyapatite microspheres were prepared using an ultrasonic atomization method. The surface morphology, phase composition, size distribution and spe-cific surface area were determined by field emission scanning electron microscopy, transmission electron microscopy,X-ray diffractometry and laser diffraction particle size analy-sis, respectively. The results indicate that the hydroxyapatite microspheres are composed of nanosized crystals and have porous surface morphology. The specific surface areas are different before sintering, and have a slight difference after sintering. The size distribution of the microspheres added with Lopon 885 is narrow and the average size is smaller than those fabricated without the addition of Lopon 885. Besides,the impurity phase, tetracalcium phosphate, appeared during ultrasonic atomizing procedure, and can be completely removed after sintering at 650℃ for 1 h.

  8. Analysis of ultrasound propagation in a steel pipe using ultrasonic pulse doppler method

    International Nuclear Information System (INIS)

    Thermal powers of nuclear reactors are calculated by the enthalpy difference between reactor feed water and main steam. Improvement of the measurement accuracy in the flow rate measurements of reactor feed water enables us to uprate reactor thermal power, called MUR (Measurement Uncertainly Recapture) uprate. The ultrasonic pulse Doppler system is expected to be a suitable method featuring the capability o measuring the flow profile directly in a pipe. For the optimum measurements, ultrasound path from ultrasonic transducer into the fluid through steel pipe wall should be carefully predicted in high temperature water. This paper presents analytical results of ultrasound propagation using FEM simulation code and experimental results of pipe flow rate at high temperature thermal conditions. (author)

  9. Ultrasonic method for measurement of D2O concentration

    International Nuclear Information System (INIS)

    A correlation of the velocity of sound with mole percent of heavy water in D2O-H2O mixtures has been measured using a modified commercially available instrument. This is being developed as a practical method for the analysis of heavy water stored in 210 l drums. The drums need not be opened, and measurements can be made under field conditions. The application of this method would permit quick, in-field verification of drum contents in production or user facilities without having to violate drum seals

  10. An ultrasonic method for dynamic monitoring of fatigue crack initiation and growth.

    Science.gov (United States)

    Mi, Bao; Michaels, Jennifer E; Michaels, Thomas E

    2006-01-01

    Attached ultrasonic sensors can detect changes caused by crack initiation and growth if the wave path is directed through the area of critical crack formation. Dynamics of cracks opening and closing under load cause nonlinear modulation of received ultrasonic signals, enabling small cracks to be detected by stationary sensors. A methodology is presented based upon the behavior of ultrasonic signals versus applied load to detect and monitor formation and growth of cracks originating from fastener holes. Shear wave angle beam transducers operating in through transmission mode are mounted on either side of the hole such that the transmitted wave travels through the area of expected cracking. Time shift is linear with respect to load, and is well explained by path changes due to strain combined with wave speed changes due to acoustoelasticity. During subsequent in situ monitoring with unknown loads, the measured time of flight is used to estimate the load, and behavior of the received energy as a function of load is the basis for crack detection. Results are presented from low cycle fatigue tests of several aluminum specimens and illustrate the efficacy of the method in both determining the applied load and monitoring crack initiation and growth. PMID:16454266

  11. Development of pulse ultrasonic doppler method for flow rate measurement in power plant. Multilines flow rate measurement on metal pipe

    International Nuclear Information System (INIS)

    Ultrasonic Doppler method for a flow metering system has been developed. The method has the capability to obtain instantaneous velocity profiles along the ultrasonic beam. Our purpose is to apply the ultrasonic Doppler method to a flow rate measurement of feed- or recirculation- water in power plants. The principle of the flow measurement method is based on the integration of an instantaneous velocity profile over a pipe diameter. Hence, it is expected to eliminate installation problems such as entry length, also to follow transient flow rate precisely by increasing ultrasonic trans-ducers. In this paper, we report that the errors are less than 1% just below a bend and sudden expansion pipe employing three measuring lines. And then, for constructing a basic system of a flow rate measurement in power plants, a transmission of ultrasound through a metallic wall is investigated, at first. Afterward, since there is no ultrasonic reflectors in the feedwater in power plants, cavitation bubbles are induced as ultrasonic reflectors and the results are appeared that cavitation bubbles are effective when the pipe material is metallic. (author)

  12. Single-Transducer, Ultrasonic Imaging Method for High-Temperature Structural Materials Eliminates the Effect of Thickness Variation in the Image

    Science.gov (United States)

    Roth, Don J.

    1998-01-01

    NASA Lewis Research Center's Life Prediction Branch, in partnership with Sonix, Inc., and Cleveland State University, recently advanced the development of, refined, and commercialized an advanced nondestructive evaluation (NDE) inspection method entitled the Single Transducer Thickness-Independent Ultrasonic Imaging Method. Selected by R&D Magazine as one of the 100 most technologically significant new products of 1996, the method uses a single transducer to eliminate the superimposing effects of thickness variation in the ultrasonic images of materials. As a result, any variation seen in the image is due solely to microstructural variation. This nondestructive method precisely and accurately characterizes material gradients (pore fraction, density, or chemical) that affect the uniformity of a material's physical performance (mechanical, thermal, or electrical). Advantages of the method over conventional ultrasonic imaging include (1) elimination of machining costs (for precision thickness control) during the quality control stages of material processing and development and (2) elimination of labor costs and subjectivity involved in further image processing and image interpretation. At NASA Lewis, the method has been used primarily for accurate inspections of high temperature structural materials including monolithic ceramics, metal matrix composites, and polymer matrix composites. Data were published this year for platelike samples, and current research is focusing on applying the method to tubular components. The initial publicity regarding the development of the method generated 150 requests for further information from a wide variety of institutions and individuals including the Federal Bureau of Investigation (FBI), Lockheed Martin Corporation, Rockwell International, Hewlett Packard Company, and Procter & Gamble Company. In addition, NASA has been solicited by the 3M Company and Allison Abrasives to use this method to inspect composite materials that are

  13. A Digital Method for the Detection of Blood Flow Direction in Ultrasonic Doppler Systems

    Directory of Open Access Journals (Sweden)

    P. Acevedo–Contla.

    2010-01-01

    Full Text Available Doppler ultrasound systems are widely used to study blood flow and diagnosis of vascular diseases. An important characteristic of these systems is the ability to detect the direction of the blood flow. Most Doppler ultrasound systems apply a quadrature demodulation technique on the ultrasonic transducer output signal. Therefore additional treatment is necessary to separate forward and reverse flow signals. This work presents a digital method to convert signals in quadrature into directional signals using a Fast Fourier Transform (FFT approach. Validation of the method has been achieved using simulated Doppler ultrasound signals.

  14. Measurement of film thickness and void fraction in stratified horizontal gas-liquid flow using an advanced ultrasonic technique

    International Nuclear Information System (INIS)

    The main objective of this work is to present the development and assembling of a new ultrasonic system for the dynamic measurements of liquid film thickness, void fraction and liquid speed of air-water two-phase flow in a horizontal circular pipe test section by using an advanced time averaging ultrasonic technique. Together we present the experimental results of the system tests and its performance on different static and dynamic conditions of stratified air-water flow. In a stratified air-water flow through the horizontal circular pipe, one part of ultrasound pulse discharged from an emitter-receiver transducer, placed at bottom of tube, will be transmitted through the water and then reflected back to the same transducer from air-water or tube wall-water interfaces. These signals can be acquired by an oscilloscope over a period of time, stored on a computer and then plotted as the waveforms. The transit time of a pulse is calculated and converted to the distance between the interfaces, as the sound velocity in water is known at a given temperature. In this way it is possible to determine both water film thickness and void fraction. Other parameters could be deduced too as the wall thickness and the inner diameter of pipe. To determine the liquid speed a pair of ultrasonic transducers were placed respectively upstream and downstream outside tube wall on the same side. The difference in the transit time between the pair of the transducers can be measured and is used to calculate the water speed in the tube. (author)

  15. Advanced reliability methods - A review

    Science.gov (United States)

    Forsyth, David S.

    2016-02-01

    There are a number of challenges to the current practices for Probability of Detection (POD) assessment. Some Nondestructive Testing (NDT) methods, especially those that are image-based, may not provide a simple relationship between a scalar NDT response and a damage size. Some damage types are not easily characterized by a single scalar metric. Other sensing paradigms, such as structural health monitoring, could theoretically replace NDT but require a POD estimate. And the cost of performing large empirical studies to estimate POD can be prohibitive. The response of the research community has been to develop new methods that can be used to generate the same information, POD, in a form that can be used by engineering designers. This paper will highlight approaches to image-based data and complex defects, Model Assisted POD estimation, and Bayesian methods for combining information. This paper will also review the relationship of the POD estimate, confidence bounds, tolerance bounds, and risk assessment.

  16. Inverse method for effects characterization from ultrasonic b-scan images

    International Nuclear Information System (INIS)

    In service inspections of French nuclear pressure water reactor vessels are carried out automatically in complete immersion from the inside by means of ultrasonic focused probes working in the pulse echo mode. Concern has been expressed about the capabilities of performing non destructive evaluation of the Outer Surface Defects (OSD), i.e. defects located in the vicinity of the outer surface of the inspected components. OSD are insonified by both a direct field that passes through the inner surface (water/steel) of the component containing the defect and a secondary field reflected from the outer surface. Consequently, the Bscan images, containing the signatures of such defects, are complicated and their interpretation is a difficult task. This work deals with extraction of the maximum available information for characterizing OSD from ultrasonic Bscan images. Our main objectives are to obtain the type of OSD and their geometric parameters by means of two specific inverse methods. The first method is used for the identification of the geometrical parameters of the equivalent planar OSD from segmented Bscan images. Ultrasonic equivalent defect sizing model-based methods may be used to size a defect in a material by obtaining a best-fit simple equivalent shape that matches the ultrasonic observed data. We illustrate the application of such an equivalent sizing OSD method that is based on a simplified direct model. The major drawback of this identification method, as used to date, is that only a part of the useful information contained into original Bscan image, i.e. segmented Bscan image, is used for defect characterization. Moreover, it requires the availability of defect classification information (i.e. if the defect is volumetric or planer, e. g. a crack or a lack of fusion), which, generally, may be as difficult to obtain as the defect parameters themselves. Therefore, we propose a parameter estimation method for extracting complementary information on the defect

  17. A study on ultrasonic flaw sizing methods using crack tip diffraction wave

    International Nuclear Information System (INIS)

    Flaw sizing is one of the fundamental issues in the ultrasonic nondestructive evaluation of various materials, components and structures. Especially, for crack-like flaws accurate sizing is very crucial for the integrity evaluation. In this work, various flaw sizing methods that have been proposed up to now are investigated to characterize topical strengths. Furthermore, proposed in a new robust sizing method, the mode converted tip diffraction (MCTD) technique, which uses the mode converted shear waves diffracted from the crack tips for sizing. The characteristics and the performance of the MCTD method are addressed with the comparison to three different sizing methods of the tip-echo method, the time-of-flight diffraction method, and the modified time-of-flight diffraction method.

  18. A study on ultrasonic flaw sizing methods using crack tip diffraction wave

    Energy Technology Data Exchange (ETDEWEB)

    Song, Sung Jin; Choi, Yong Seok [Sungkyunkwan University, Seoul (Korea, Republic of)

    1999-11-15

    Flaw sizing is one of the fundamental issues in the ultrasonic nondestructive evaluation of various materials, components and structures. Especially, for crack-like flaws accurate sizing is very crucial for the integrity evaluation. In this work, various flaw sizing methods that have been proposed up to now are investigated to characterize topical strengths. Furthermore, proposed in a new robust sizing method, the mode converted tip diffraction (MCTD) technique, which uses the mode converted shear waves diffracted from the crack tips for sizing. The characteristics and the performance of the MCTD method are addressed with the comparison to three different sizing methods of the tip-echo method, the time-of-flight diffraction method, and the modified time-of-flight diffraction method.

  19. Advanced Fine Particulate Characterization Methods

    Energy Technology Data Exchange (ETDEWEB)

    Steven Benson; Lingbu Kong; Alexander Azenkeng; Jason Laumb; Robert Jensen; Edwin Olson; Jill MacKenzie; A.M. Rokanuzzaman

    2007-01-31

    The characterization and control of emissions from combustion sources are of significant importance in improving local and regional air quality. Such emissions include fine particulate matter, organic carbon compounds, and NO{sub x} and SO{sub 2} gases, along with mercury and other toxic metals. This project involved four activities including Further Development of Analytical Techniques for PM{sub 10} and PM{sub 2.5} Characterization and Source Apportionment and Management, Organic Carbonaceous Particulate and Metal Speciation for Source Apportionment Studies, Quantum Modeling, and High-Potassium Carbon Production with Biomass-Coal Blending. The key accomplishments included the development of improved automated methods to characterize the inorganic and organic components particulate matter. The methods involved the use of scanning electron microscopy and x-ray microanalysis for the inorganic fraction and a combination of extractive methods combined with near-edge x-ray absorption fine structure to characterize the organic fraction. These methods have direction application for source apportionment studies of PM because they provide detailed inorganic analysis along with total organic and elemental carbon (OC/EC) quantification. Quantum modeling using density functional theory (DFT) calculations was used to further elucidate a recently developed mechanistic model for mercury speciation in coal combustion systems and interactions on activated carbon. Reaction energies, enthalpies, free energies and binding energies of Hg species to the prototype molecules were derived from the data obtained in these calculations. Bimolecular rate constants for the various elementary steps in the mechanism have been estimated using the hard-sphere collision theory approximation, and the results seem to indicate that extremely fast kinetics could be involved in these surface reactions. Activated carbon was produced from a blend of lignite coal from the Center Mine in North Dakota and

  20. Application of ultrasonic CT method in nondestructive detection of interior defects in large scale concrete structural member of bridge

    Institute of Scientific and Technical Information of China (English)

    Xiaopei ZHANG; Jianhui QIU; Jianjun NIU; Lizhi DU; Xuege WANG

    2008-01-01

    The ultrasonic computed tomography (USCT) method is derived from the basic principles of X-ray section scanning. This method records the arriving times of ultrasonic wave between the probes and the sources to calculate the elastic wave velocity values in the section using the arrival times. Through analyzed the distribution of elastic wave velocity in aim area, the information of the strength and the homogeneity of the investigated zone could be got indirectly. The authors introduced the operational principle of USCT and a practical case of using this method to detect the interior defects in large scale concrete structural member. Compared with other exploration methods, this method is more efficient and accurate.

  1. A study on scattered fields analysis of ultrasonic SH-wave by boundary element method

    International Nuclear Information System (INIS)

    In this paper, the SH-wave scattering by multi-defects and inclusion using Boundary Element Method is studied. The effects of shape and distance of defects on transmitted and reflected fields are considered. The interaction of multi-defects in SH-wave scattering is also investigated. Numerical calculations by the BEM have been carried out to predict near field solution of scattered fields of ultrasonic SH-wave. The presented results can be used to improve the detection sensitivity and pursue quantitative nondestructive evaluation for inverse problem.

  2. Simple method for measuring vibration amplitude of high power airborne ultrasonic transducer: using thermo-couple.

    Science.gov (United States)

    Saffar, Saber; Abdullah, Amir

    2014-03-01

    Vibration amplitude of transducer's elements is the influential parameters in the performance of high power airborne ultrasonic transducers to control the optimum vibration without material yielding. The vibration amplitude of elements of provided high power airborne transducer was determined by measuring temperature of the provided high power airborne transducer transducer's elements. The results showed that simple thermocouples can be used both to measure the vibration amplitude of transducer's element and an indicator to power transmission to the air. To verify our approach, the power transmission to the air has been investigated by other common method experimentally. The experimental results displayed good agreement with presented approach. PMID:24246149

  3. The maturity characterization of orange fruit by using high frequency ultrasonic echo pulse method

    OpenAIRE

    ABOUDAOUD, Idriss; FAIZ, BOUAZZA; AASSIF, EL HOUCEIN; Moudden, Ali; IZBAIM, DRIS; EL ABASSI, DRIS; MALAININE, MOHAMED

    2012-01-01

    In this present work, our objective is to study the feasibility of the control of the maturity of orange fruit by the ultrasonic echo pulse method with immersion in water. This study relates to two varieties of orange (Navel and Mandarin) which are the most harvested particularly in the region of Souss-Massa-Drâa in Morocco. Contrary to the works already published in this field, we worked in the high frequencies by the means of a focusing transducer with 20MHz as a central frequency. By takin...

  4. A novel preparation method for drug nanocrystals and characterization by ultrasonic spray-assisted electrostatic adsorption

    Science.gov (United States)

    Gao, Bing; Wang, Jun; Wang, Dunju; Zhu, Ziqiang; Qiao, Zhiqiang; Yang, Guangcheng; Nie, Fude

    2013-01-01

    Purpose The purpose of this study was to develop a novel and continuous method for preparing a nanosized particle of drug crystals and to characterize its properties. Materials and methods A new apparatus was introduced to crystallize nanosized drug crystals of amitriptyline hydrochloride as a model drug. The samples were prepared in the pure state by ultrasonic spray, and elaborated deposition was completed via electrostatic adsorption. Scanning electron microscopy, X-ray powder diffraction, and atomic force microscopy were used to characterize the size of the particles; this was subsequently followed by differential scanning calorimetry. Results and discussion Nanoparticles of drug crystals were successfully prepared. The size of the drug crystals ranged from 20 nm to 400 nm; the particle size of amitriptyline hydrochloride was approximately 71 nm. The particles were spherical and rectangular in shape. Moreover, the melting point of the nanoparticles decreased from 198.2°C to 196.3°C when compared to raw particle crystals. Furthermore, the agglomeration effect was also attenuated as a result of electrostatic repulsion among each particle when absorbed, and depositing on the inner wall of the gathering unit occurred under the electrostatic effect. Conclusion Ultrasonic spray-assisted electrostatic adsorption is a very effective and continuous method to produce drug nanocrystals. This method can be applied to poorly water-soluble drugs, and it can also be a very effective alternative for industrial production. Once the working parameters are given, drug nanocrystals will be produced continuously. PMID:24143097

  5. Detection of moving capillary front in porous rocks using X-ray and ultrasonic methods

    Directory of Open Access Journals (Sweden)

    Christian eDavid

    2015-07-01

    Full Text Available Several methods are compared for the detection of moving capillary fronts in spontaneous imbibition experiments where water invades dry porous rocks. These methods are: (i the continuous monitoring of the mass increase during imbibition, (ii the imaging of the water front motion using X-ray CT scanning, (iii the use of ultrasonic measurements allowing the detection of velocity, amplitude and spectral content of the propagating elastic waves, and (iv the combined use of X-ray CT scanning and ultrasonic monitoring. It is shown that the properties of capillary fronts depend on the heterogeneity of the rocks, and that the information derived from each method on the dynamics of capillary motion can be significantly different. One important result from the direct comparison of the moving capillary front position and the P wave attributes is that the wave amplitude is strongly impacted before the capillary front reaches the sensors, in contrast with the velocity change which is concomitant with the fluid front arrival in the sensors plane.

  6. Ultrasonic tests. Pt. 1

    International Nuclear Information System (INIS)

    Nondestructive testing (NDT) plays an important part in the field of nuclear power plants operation. The report is concentrated to the primary loop components' ultrasonic NDT. It includes inspection techniques used during fabrication and in service. While a second part is dealing with advanced NDT methods, this first presentation introduces into the variety of ultrasonic testing procedures. After a treatment of the physical background the appropriate choice of equipment and techniques in respect of material, geometry and accessibility will be discussed. The state-of-the-art for detection, location, normalization, classification and sizing of defects will be presented. Finally, evaluation of faults and accept/reject criteria (e.g. based on fracture mechanics) together with the qualification of NDE personnel are concluding the contribution. (orig./RW)

  7. Advanced computational electromagnetic methods and applications

    CERN Document Server

    Li, Wenxing; Elsherbeni, Atef; Rahmat-Samii, Yahya

    2015-01-01

    This new resource covers the latest developments in computational electromagnetic methods, with emphasis on cutting-edge applications. This book is designed to extend existing literature to the latest development in computational electromagnetic methods, which are of interest to readers in both academic and industrial areas. The topics include advanced techniques in MoM, FEM and FDTD, spectral domain method, GPU and Phi hardware acceleration, metamaterials, frequency and time domain integral equations, and statistics methods in bio-electromagnetics.

  8. 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. PMID:27245962

  9. Improvement to defect detection by ultrasonic data processing: the DTVG method; Amelioration de detection de defaut par ultrasons: la methode DTVG

    Energy Technology Data Exchange (ETDEWEB)

    Francois, D.

    1995-10-01

    The cast elbows of the pipes of the principal primary circuit of French PWR, made of austenitic-ferritic stainless steel, pose problems to control. In order to improve the ultrasonic detection of defects in coarse-grained materials, we propose a method (called DTVG) based on the statistic study of the spatial stability of events contained in temporal signals. At the Beginning, the method was developed during a thesis (G. Corneloup, 1998) to improve the detection of cracks in thin thickness austenitic welds. Here, we propose to adapt the DTVG method and estimate its performances in detection of defects in thick materials representative of cast austenitic-ferritic elbows steels. The first objective of the study is adapting the original treatment applied to the thin thickness austenitic welds for the detection of defects in thick thickness austenitic-ferritic cast steels. The second objective consist of improving the algorithm to take in account the difference between thin and thick material and estimating the performances of the DTVG method in detection in specimen block with artificial defects. This work has led to adapt the original DTVG method to control thick cast austenitic-ferritic specimen (80 mm) under normal and oblique incidence. More, the study has allowed to make the the treatment automatic (automatic research of parameters). The results have shown that the DTVG method is fitted to detect artificial defects in thick cast austenitic-ferritic sample steel. All the defects in the specimen block have been detected without revealing false indication. (author). 4 refs., 4 figs.

  10. Determination of corrective factors for an ultrasonic flow measuring method in pipes accounting for perturbations

    International Nuclear Information System (INIS)

    By current ultrasonic flow measuring equipment (UFME) the mean velocity is measured for one or two measuring paths. This mean velocity is not equal to the velocity averaged over the flow cross-section, by means of which the flow rate is calculated. This difference will be found already for axially symmetrical, fully developed velocity profiles and, to a larger extent, for disturbed profiles varying in flow direction and for nonsteady flow. Corrective factors are defined for steady and nonsteady flows. These factors can be derived from the flow profiles within the UFME. By mathematical simulation of the entrainment effect the influence of cross and swirl flows on various ultrasonic measuring methods is studied. The applied UFME with crossed measuring paths is shown to be largely independent of cross and swirl flows. For evaluation in a computer of velocity network measurements in circular cross-sections the equations for interpolation and integration are derived. Results of the mathematical method are the isotach profile, the flow rate and, for fully developed flow, directly the corrective factor. In the experimental part corrective factors are determined in nonsteady flow in a measuring plane before and in form measuring planes behind a perturbation. (orig./RW)

  11. An alternative ultrasonic method for measuring the elastic properties of cortical bone

    CERN Document Server

    Pithioux, M; Chabrand, P; Pithioux, Martine

    2002-01-01

    We studied the elastic properties of bone to analyze its mechanical behavior. The basic principles of ultrasonic methods are now well established for varying isotropic media, particularly in the field of biomedical engineering. However, little progress has been made in its application to anisotropic materials. This is largely due to the complex nature of wave propagation in these media. In the present study, the theory of elastic waves is essential because it relates the elastic moduli of a material to the velocity of propagation of these waves along arbitrary directions in a solid. Transducers are generally placed in contact with the samples which are often cubes with parallel faces that are difficult to prepare. The ultrasonic method used here is original, a rough preparation of the bone is sufficient and the sample is in rotation. Moreover, to analyze heterogeneity of the structure we measure velocities in different points on the sample. The aim of the present study was to determine in vitro the anisotropi...

  12. A novel pyroelectric method of determining ultrasonic transducer output power: device concept, modeling, and preliminary studies.

    Science.gov (United States)

    Zeqiri, Bajram; Gélat, Pierre N; Barrie, Jill; Bickley, Catherine J

    2007-11-01

    This paper describes a new thermally based method of monitoring acoustic output power generated by ultrasonic transducers. Its novelty lies in the exploitation of the pyroelectric properties of a thin membrane of polyvinylidene fluoride (PVDF). The membrane is backed by a thick layer of polyurethane rubber that is extremely attenuating to ultrasound, with the result that the majority of the applied acoustic power is absorbed within a few millimeters of the membrane-backing interface. Through the resultant rapid increase in temperature of the membrane, a voltage is generated across its electrodes whose magnitude is proportional to the rate of change of temperature with respect to time. Changes in the pyroelectric voltage generated by switching the transducer ON and OFF are related to the acoustic power delivered by the transducer. Features of the technique are explored through the development of a simple one-dimensional model. An experimental evaluation of the potential secondary measurement technique is also presented, covering the frequency range 1 to 5 MHz, for delivered powers up to a watt. Predictions of the sensor output signals, as well as the frequency dependent sensitivity, are in good agreement with observation. The potential of the new method as a simple, rapid means of providing traceable ultrasonic power measurements is outlined. PMID:18051166

  13. Production of Biodiesel from Lipid of Phytoplankton Chaetoceros calcitrans through Ultrasonic Method

    Directory of Open Access Journals (Sweden)

    Raymond Kwangdinata

    2014-01-01

    Full Text Available A research on production of biodiesel from lipid of phytoplankton Chaetoceros calcitrans through ultrasonic method has been done. In this research, we carried out a series of phytoplankton cultures to determine the optimum time of growth and biodiesel synthesis process from phytoplankton lipids. Process of biodiesel synthesis consists of two steps, that is, isolation of phytoplankton lipids and biodiesel synthesis from those lipids. Oil isolation process was carried out by ultrasonic extraction method using ethanol 96%, while biodiesel synthesis was carried out by transesterification reaction using methanol and KOH catalyst under sonication. Weight of biodiesel yield per biomass Chaetoceros calcitrans is 35.35%. Characterization of biodiesel was well carried out in terms of physical properties which are density and viscosity and chemical properties which are FFA content, saponification value, and iodine value. These values meet the American Society for Testing and Materials (ASTM D6751 standard levels, except for the viscosity value which was 1.14 g·cm−3.

  14. Quantitative evaluation of ultrasonic wave propagation in inhomogeneous anisotropic austenitic welds using 3D ray tracing method. Numerical and experimental validation

    Energy Technology Data Exchange (ETDEWEB)

    Kolkoori, Sanjeevareddy

    2014-07-01

    Austenitic welds and dissimilar welds are extensively used in primary circuit pipes and pressure vessels in nuclear power plants, chemical industries and fossil fuelled power plants because of their high fracture toughness, resistance to corrosion and creep at elevated temperatures. However, cracks may initiate in these weld materials during fabrication process or stress operations in service. Thus, it is very important to evaluate the structural integrity of these materials using highly reliable non-destructive testing (NDT) methods. Ultrasonic non-destructive inspection of austenitic welds and dissimilar weld components is complicated because of anisotropic columnar grain structure leading to beam splitting and beam deflection. Simulation tools play an important role in developing advanced reliable ultrasonic testing (UT) techniques and optimizing experimental parameters for inspection of austenitic welds and dissimilar weld components. The main aim of the thesis is to develop a 3D ray tracing model for quantitative evaluation of ultrasonic wave propagation in an inhomogeneous anisotropic austenitic weld material. Inhomogenity in the anisotropic weld material is represented by discretizing into several homogeneous layers. According to ray tracing model, ultrasonic ray paths are traced during its energy propagation through various discretized layers of the material and at each interface the problem of reflection and transmission is solved. The influence of anisotropy on ultrasonic reflection and transmission behaviour in an anisotropic austenitic weld material are quantitatively analyzed in three dimensions. The ultrasonic beam directivity in columnar grained austenitic steel material is determined three dimensionally using Lamb's reciprocity theorem. The developed ray tracing model evaluates the transducer excited ultrasonic fields accurately by taking into account the directivity of the transducer, divergence of the ray bundle, density of rays and phase

  15. A New Method for Descaling Wool Fibres by Nano Abrasive Calcium Carbonate Particles in Ultrasonic Bath

    Directory of Open Access Journals (Sweden)

    Ali rezaghasemi

    2016-08-01

    Full Text Available Up to now, the most conventional methods for descaling of wool fibre are based on chemical degradation and resin covering of scales or a combination of them. These methods are producing wastewater and can cover physical properties of the fibres beside scales orderly. In this study, a new and clean method is developed on the basis of abrasion effect of calcium carbonate Nano particles (CCNP in an ultrasonic bath. Woolen Samples (fibre and yarn were sonicated with different levels of CCNP. Tensile properties of the yarns, directional friction effect of the fibres and scanning electron microscope images of the fibres were studied. Test results showed that sonicated Nano treatment of woolyarn reduced its tenacity, extension and work of rupture and increased its coefficient of friction. Scanning electron microscope images of fibres and measurement of fibres directional displacement confirmed descaling of Nano abrasive treated wool samples in comparison to the raw wool.

  16. A Novel Three-Head Ultrasonic System for Distance Measurements Based on the Correlation Method

    Directory of Open Access Journals (Sweden)

    Gądek Krzysztof

    2014-12-01

    Full Text Available A novel double-emitter ultrasonic system for distance measurements based on the correlation method is presented. The proposed distance measurement method may be particularly useful in difficult conditions, e.g. for media parameters undergoing fast changes or in cases when obstacles and mechanical interference produce false reflections. The system is a development of a previously studied single-head idea. The present article covers a comparison of the two systems in terms of efficiency and precision. Experimental research described in this paper indicated that adding the second head improved the measurement exactness – standard deviation decreased by 40%. The correlation method is also described in detail, also giving the criterion for the quality of the measurement signal.

  17. Flow acoustics modelling and implications for ultrasonic flow measurement based on the transit-time method.

    Science.gov (United States)

    Willatzen, M

    2004-05-01

    A comparison between three mathematical models frequently used in flow acoustics is presented and discussed with respect to ultrasonic flow-meter performance based on the transit-time method. The flow-meter spoolpiece geometry is assumed to be a cylindrical pipe. Semi-analytical calculations employing the Frobenius power series expansion method are shown for the cases of a constant-, linear-, parabolic-, and cubic-flow profiles although the Frobenius method presented can be applied to any smooth flow profile. It is shown that the so-called deviation of measurement, often used as a measure of the flow-meter accuracy, is strongly dependent on the acoustic mode excited and the flow profile. Furthermore, differences with respect to deviation of measurement results exist among the three mathematical models analyzed. PMID:15110538

  18. Advances in structure research by diffraction methods

    CERN Document Server

    Brill, R

    1970-01-01

    Advances in Structure Research by Diffraction Methods reviews advances in the use of diffraction methods in structure research. Topics covered include the dynamical theory of X-ray diffraction, with emphasis on Ewald waves in theory and experiment; dynamical theory of electron diffraction; small angle scattering; and molecular packing. This book is comprised of four chapters and begins with an overview of the dynamical theory of X-ray diffraction, especially in terms of how it explains all the absorption and propagation properties of X-rays at the Bragg setting in a perfect crystal. The next

  19. An ultrasonic-accelerated oxidation method for determining the oxidative stability of biodiesel.

    Science.gov (United States)

    Avila Orozco, Francisco D; Sousa, Antonio C; Domini, Claudia E; Ugulino Araujo, Mario Cesar; Fernández Band, Beatriz S

    2013-05-01

    Biodiesel is considered an alternative energy because it is produced from fats and vegetable oils by means of transesterification. Furthermore, it consists of fatty acid alkyl esters (FAAS) which have a great influence on biodiesel fuel properties and in the storage lifetime of biodiesel itself. The biodiesel storage stability is directly related to the oxidative stability parameter (Induction Time - IT) which is determined by means of the Rancimat® method. This method uses condutimetric monitoring and induces the degradation of FAAS by heating the sample at a constant temperature. The European Committee for Standardization established a standard (EN 14214) to determine the oxidative stability of biodiesel, which requires it to reach a minimum induction period of 6h as tested by Rancimat® method at 110°C. In this research, we aimed at developing a fast and simple alternative method to determine the induction time (IT) based on the FAAS ultrasonic-accelerated oxidation. The sonodegradation of biodiesel samples was induced by means of an ultrasonic homogenizer fitted with an immersible horn at 480Watts of power and 20 duty cycles. The UV-Vis spectrometry was used to monitor the FAAS sonodegradation by measuring the absorbance at 270nm every 2. Biodiesel samples from different feedstock were studied in this work. In all cases, IT was established as the inflection point of the absorbance versus time curve. The induction time values of all biodiesel samples determined using the proposed method was in accordance with those measured through the Rancimat® reference method by showing a R(2)=0.998.

  20. [Efficacy of surgical treatment of patients for an acute lactational mastitis using radiofrequency scalpel and ozono-ultrasonic method].

    Science.gov (United States)

    Ioffe, I V; Chernova, N V

    2013-01-01

    According to microbial investigation data, conducted preoperatively, intraoperatively, in 7 days postoperatively for an acute purulent lactational mastitis, there was noted significant reduction of the wound microbial soiling while application of radiofrequency scalpel and ozono-ultrasonic method in comparison with such while application of conventional methods of treatment.

  1. Comparison of Polyacetylene Content in Organically and Conventionally Grown Carrots Using a Fast Ultrasonic Liquid Extraction Method

    DEFF Research Database (Denmark)

    Søltoft, Malene; Eriksen, Morten Rosbjørn; Träger, Anne Wibe Brændholt;

    2010-01-01

    A rapid and sensitive analytical method for quantification of polyacetylenes in carrot roots was developed. The traditional extraction method (stirring) was compared to a new ultrasonic liquid processor (ULP)-based methodology using high-performance liquid chromatography−ultraviolet (HPLC−UV) and...

  2. Advanced analysis methods in particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, Pushpalatha C.; /Fermilab

    2010-10-01

    Each generation of high energy physics experiments is grander in scale than the previous - more powerful, more complex and more demanding in terms of data handling and analysis. The spectacular performance of the Tevatron and the beginning of operations of the Large Hadron Collider, have placed us at the threshold of a new era in particle physics. The discovery of the Higgs boson or another agent of electroweak symmetry breaking and evidence of new physics may be just around the corner. The greatest challenge in these pursuits is to extract the extremely rare signals, if any, from huge backgrounds arising from known physics processes. The use of advanced analysis techniques is crucial in achieving this goal. In this review, I discuss the concepts of optimal analysis, some important advanced analysis methods and a few examples. The judicious use of these advanced methods should enable new discoveries and produce results with better precision, robustness and clarity.

  3. Development of ultrasonic pulse-train Doppler method for velocity profile and flowrate measurement

    Science.gov (United States)

    Wada, Sanehiro; Furuichi, Noriyuki; Shimada, Takashi

    2016-11-01

    We present a novel technique for measuring the velocity profile and flowrate in a pipe. This method, named the ultrasonic pulse-train Doppler method (UPTD), has the advantages of expanding the velocity range and setting the smaller measurement volume with low calculation and instrument costs in comparison with the conventional ultrasonic pulse Doppler method. The conventional method has limited measurement of the velocity range due to the Nyquist sampling theorem. In addition, previous reports indicate that a smaller measurement volume increases the accuracy of the measurement. In consideration of the application of the conventional method to actual flow fields, such as industrial facilities and power plants, the issues of velocity range and measurement volume are important. The UPTD algorithm, which exploits two pulses of ultrasound with a short interval and envelope detection, is proposed. Velocity profiles calculated by this algorithm were examined through simulations and excellent agreement was found in all cases. The influence of the signal-to-noise ratio (SNR) on the algorithm was also estimated. The result indicates that UPTD can measure velocity profiles with high accuracy, even under a small SNR. Experimental measurements were conducted and the results were evaluated at the national standard calibration facility of water flowrate in Japan. Every detected signal forms a set of two pulses and the enveloped line can be observed clearly. The results show that UPTD can measure the velocity profiles over the pipe diameter, even if the velocities exceed the measurable velocity range. The measured flowrates were under 0.6% and the standard deviations for all flowrate conditions were within  ±0.38%, which is the uncertainty of the flowrate measurement estimated in the previous report. In conclusion, UPTD provides superior accuracy and expansion of the velocity range.

  4. A method to obtain reference images for evaluation of ultrasonic tissue characterization techniques

    DEFF Research Database (Denmark)

    Jensen, M.S.; Wilhjelm, Jens E.; Sahl, B.;

    2002-01-01

    present in the biological tissue scanned in vitro. A 30 x 10 x 2 mm(3) piece of formalin fixed porcine tissue was molded into an agar block, which on the top surface, contained a set of fiducial markers, spaced 2.5 mm. The block was submerged into 20 degreesC water and a set of parallel 7.5 MHz spatial......A general problem when evaluating ultrasonic methods for tissue characterization is that "a golden standard" is seldom known. This paper describes a manual method to obtain a reference image, with the same geometry as the ultrasound image, indicating spatial location of the different tissue types...... compound ultrasound images of tissue and fiducial markers were recorded each 0.5 mm. Guided by the fiducial markers, the agar block was subsequently cut into slices 2.5 mm thick, photographed and finally analyzed histologically identifying these tissues: collagen rich, collagen poor, micro vessels and...

  5. Subsection method of fatigue design for welded joints treated by ultrasonic peening

    Institute of Scientific and Technical Information of China (English)

    Wang Ting; Wang Dongpo; Huo Lixing; Zhang Yufeng

    2006-01-01

    Concerning the notable difference between the S-N curve slope of welded joints treated by ultrasonic peening treatment (UPT) and that of as-welded joints, the subsection method is put forward for fatigue design of welded joints treated by UPT, using the design method of nominal S-N curves. Results show that, in medium life zone, strength grade of the fatigue design curves for UPT welded joints is two grades higher than that for as-welded joints. Furthermore, in medium life zone, strength grade of the fatigue design curves for UPT welded joints is three grades lower than that in long life zone.Conclusion of the comparison is that as for different joint types in different life zones, fatigue design should be processed according to different S-N curves respectively.

  6. Ultrasonic Digital Communication System for a Steel Wall Multipath Channel: Methods and Results

    Energy Technology Data Exchange (ETDEWEB)

    TL Murphy

    2006-02-16

    As of the development of this thesis, no commercially available products have been identified for the digital communication of instrumented data across a thick ({approx} 6 n.) steel wall using ultrasound. The specific goal of the current research is to investigate the application of methods for digital communication of instrumented data (i.e., temperature, voltage, etc.) across the wall of a steel pressure vessel. The acoustic transmission of data using ultrasonic transducers prevents the need to breach the wall of such a pressure vessel which could ultimately affect its safety or lifespan, or void the homogeneity of an experiment under test. Actual digital communication paradigms are introduced and implemented for the successful dissemination of data across such a wall utilizing solely an acoustic ultrasonic link. The first, dubbed the ''single-hop'' configuration, can communicate bursts of digital data one-way across the wall using the Differential Binary Phase-Shift Keying (DBPSK) modulation technique as fast as 500 bps. The second, dubbed the ''double-hop'' configuration, transmits a carrier into the vessel, modulates it, and retransmits it externally. Using a pulsed carrier with Pulse Amplitude Modulation (PAM), this technique can communicate digital data as fast as 500 bps. Using a CW carrier, Least Mean-Squared (LMS) adaptive interference suppression, and DBPSK, this method can communicate data as fast as 5 kbps. A third technique, dubbed the ''reflected-power'' configuration, communicates digital data by modulating a pulsed carrier by varying the acoustic impedance at the internal transducer-wall interface. The paradigms of the latter two configurations are believed to be unique. All modulation methods are based on the premise that the wall cannot be breached in any way and can therefore be viably implemented with power delivered wirelessly through the acoustic channel using ultrasound. Methods

  7. Ultrastructural investigation of root canal dentine surface after application of active ultrasonic method

    OpenAIRE

    Mitić Aleksandar; Mitić Nadica; Muratovska Ilijana; Stojanovska Vera; Popovska Lidija; Mitić Vladimir

    2008-01-01

    INTRODUCTION The basic work principle of all ultrasonic techniques is the piezoelectric effect of producing high frequency ultrasounds of small length, which are transmitted over the endodontic extensions or canal instruments into the root canal. When in contact with the tissue, ultrasonic vibrations are converted into mechanical oscillations. Ultrasonic waves and the obtained oscillations along with the synergic effect of irrigation bring about the elimination of smear layer from the root ca...

  8. Catalytic activity of acid and base with different concentration on sol-gel kinetics of silica by ultrasonic method.

    Science.gov (United States)

    Das, R K; Das, M

    2015-09-01

    The effects of both acid (acetic acid) and base (ammonia) catalysts in varying on the sol-gel synthesis of SiO2 nanoparticles using tetra ethyl ortho silicate (TEOS) as a precursor was determined by ultrasonic method. The ultrasonic velocity was received by pulsar receiver. The ultrasonic velocity in the sol and the parameter ΔT (time difference between the original pulse and first back wall echo of the sol) was varied with time of gelation. The graphs of ln[ln1/ΔT] vs ln(t), indicate two region - nonlinear region and a linear region. The time corresponds to the point at which the non-linear region change to linear region is considered as gel time for the respective solutions. Gelation time is found to be dependent on the concentration and types of catalyst and is found from the graphs based on Avrami equation. The rate of condensation is found to be faster for base catalyst. The gelation process was also characterized by viscosity measurement. Normal sol-gel process was also carried out along with the ultrasonic one to compare the effectiveness of ultrasonic. The silica gel was calcined and the powdered sample was characterized with scanning electron microscopy, energy dispersive spectra, X-ray diffractogram, and FTIR spectroscopy. PMID:25600993

  9. Prediction of mechanical properties of hot rolled steel by ultrasonic method

    International Nuclear Information System (INIS)

    The ultrasonic attenuation and the velocity in hot rolled steel have been evaluated by ultrasonic contact measurement. The measured attenuation is calibrated by diffraction correction integral suggested by Lommel. The attenuation is also calculated by the model suggested by Mason. The agreement between the experimentally determined attenuation and the calculated one was good. As the results, the mechanical properties of the ferrite plus pearlite steels could be assessed by the ultrasonic attenuation. The mechanical properties of the martensite plus bainite steels could be assessed by the ultrasonic velocity.

  10. Development of ultrasonic testing technique for anchor bolts. Part 2. Development of nondestructive examination method for fatigue cracks by ultrasonic phased array technology

    International Nuclear Information System (INIS)

    Cracks may initiate in anchor bolts in nuclear power plants due to a severe earthquake. Moreover, number of fatigue cracks have been found in the anchor bolts in aged nuclear and thermal power plants. Ultrasonic phased array technology is effective to detect such cracks, and a method is proposed to determine crack depth by using refection echo at the vicinity of crack according to simulation results of wave propagation within bolts. However, detectability of crack and applicability of this method for crack sizing are not known though they are essential to evaluation of crack in bolts by ultrasonic phased array technology. In this report, we prepared M24 and M30 bolt specimens with various slits and fatigue cracks introduced. Three linear array probes with respective frequency of 2, 5 and 10 MHz are used to measure these specimens. The investigation of fracture surface is also performed after finishing all measurements. Measurement results show the following: (1) the frequency of 10 MHz is more appropriate than frequencies of 5 and 2 MHz for detecting crack in bolts; (2) it is easy to detect 1-mm-deep cracks; and (3) it is possible to determine crack depth for M30 bolts with the deviation of 2 mm from actual depth by proposed method, but difficult for M24 bolts. (author)

  11. Mathematics for natural scientists II advanced methods

    CERN Document Server

    Kantorovich, Lev

    2016-01-01

    This book covers the advanced mathematical techniques useful for physics and engineering students, presented in a form accessible to physics students, avoiding precise mathematical jargon and laborious proofs. Instead, all proofs are given in a simplified form that is clear and convincing for a physicist. Examples, where appropriate, are given from physics contexts. Both solved and unsolved problems are provided in each chapter. Mathematics for Natural Scientists II: Advanced Methods is the second of two volumes. It follows the first volume on Fundamentals and Basics.

  12. Marine rock physical flume experiment: The method of seafloor shallow sediment recognition by ultrasonic physical attributes

    Science.gov (United States)

    Wang, Qing; Wang, Yun; Hu, Xiaoya; Zhang, Jianli; Guo, Shiguang

    2015-04-01

    It's a key problem to recognize the kinds of sediments in the ocean bottom during an acoustic survey or seismic exploration. In this paper, an ultrasonic rock physics experiment was introduced in the flume, which simulated different sedimentary types of ocean bottom, such as stone, fine sand, coarse sand, silt and cement. After processing the simulated acoustic data, some physical attributes, which are sensitive to different types of sediment, was found. In which, the weighted average frequency attribute can distinguish the coarse sand, silt and stone substrate if combined with sweetness attribute. The instantaneous quality factor (Q) attribute highlights the cement restrained with the weighted average frequency attribute. Through analyzing the relationships between porosity, density and these sensitive acoustic attributes, the types of sediment in the flume can be deduced and inversed by artificial neural network method.

  13. Preparation of Al/Si functionally graded materials using ultrasonic separation method

    Directory of Open Access Journals (Sweden)

    Zhang Zhongtao

    2008-08-01

    Full Text Available Functionally graded materials (FGM have been widely used in many industries such as aerospace, energy and electronics. In this experimental study of fabricating FGM, an approach was developed to prepare Al/Si FGM using power ultrasonic separation method. Material sample with continuously changing composition and performance/properties was successfully produced. Results showed that the microstructure of the FGM sample transited, from its top to bottom, from the hypereutectic structure with a large quantity of primary Si gradually to the eutectic, and fi nally to the hypoeutectic with numerous primary Al dendrites. The distribution of primary Si and microhardness of the FGM sample also presented graded characteristics, resulting that the wear resistance of the FGM sample decreased from top to bottom. Preliminary discussion was made on the mechanism of the formation of Al/Si FGM.

  14. Preparation of Al/Si functionally graded materials using ultrasonic separation method

    Institute of Scientific and Technical Information of China (English)

    Zhang Zhongtao; LI Tingju; Yue Hongyun; Zhang Jian; Li Jie

    2008-01-01

    Functionally graded materials (FGM) have been widely used in many industries such as aerospace, energy and electronics. In this experimental study of fabricating FGM, an approach was developed to prepare Al/Si FGM using power ultrasonic separation method. Material sample with continuously changing composition and performance/properties was successfully produced. Results showed that the microstructure of the FGM sample transited, from its top to bottom, from the hypereutectic structure with a large quantity of primary Si gradually to the eutectic, and finally to the hypoeutectic with numerous primary AI dendrites. The distribution of primary Si and microhardness of the FGM sample also presented graded characteristics, resulting that the wear resistance of the FGM sample decreased from top to bottom. Preliminary discussion was made on the mechanism of the formation of Al/Si FGM.

  15. Ultrasonic Imaging in Liquid Sodium: A Differential Method for Damages Detection

    Science.gov (United States)

    Lubeigt, Emma; Mensah, Serge; Chaix, Jean-François; Rakotonarivo, Sandrine; Gobillot, Gilles; Baqué, François

    The fourth generation of nuclear reactor can use liquid sodium as the core coolant. Under-sodium imaging aims at checking the health of immersed structures and especially at detecting and characterizing potential hazardous damage. The differential approach allows detecting a perturbation by comparison with a reference measurement and by focusing back to any change in the inspected region. The imaging method relies on the adequate combination of two computed ultrasonic fields, one forward and one adjoint. The adjoint field design offers new opportunities to reconstruct either the "scattered" or "shadow" fields respectively in order to form an image of the illuminated contours of an inclusion and an image of the shadow field induced by the presence of that inclusion. Numerical simulations have been carried out to illustrate the complementarycontent of the information conveyed by each of the reconstructions.

  16. Pulse-Echo Ultrasonic Imaging Method for Eliminating Sample Thickness Variation Effects

    Science.gov (United States)

    Roth, Don J. (Inventor)

    1997-01-01

    A pulse-echo, immersion method for ultrasonic evaluation of a material which accounts for and eliminates nonlevelness in the equipment set-up and sample thickness variation effects employs a single transducer and automatic scanning and digital imaging to obtain an image of a property of the material, such as pore fraction. The nonlevelness and thickness variation effects are accounted for by pre-scan adjustments of the time window to insure that the echoes received at each scan point are gated in the center of the window. This information is input into the scan file so that, during the automatic scanning for the material evaluation, each received echo is centered in its time window. A cross-correlation function calculates the velocity at each scan point, which is then proportionalized to a color or grey scale and displayed on a video screen.

  17. Standard practice for digital imaging and communication in nondestructive evaluation (DICONDE) for ultrasonic test methods

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This practice facilitates the interoperability of ultrasonic imaging equipment by specifying image data transfer and archival storage methods in commonly accepted terms. This document is intended to be used in conjunction with Practice E 2339 on Digital Imaging and Communication in Nondestructive Evaluation (DICONDE). Practice E 2339 defines an industrial adaptation of the NEMA Standards Publication titled Digital Imaging and Communications in Medicine (DICOM, see http://medical.nema.org), an international standard for image data acquisition, review, transfer and archival storage. The goal of Practice E 2339, commonly referred to as DICONDE, is to provide a standard that facilitates the display and analysis of NDE test results on any system conforming to the DICONDE standard. Toward that end, Practice E 2339 provides a data dictionary and set of information modules that are applicable to all NDE modalities. This practice supplements Practice E 2339 by providing information object definitions, information ...

  18. An Ultrasonic-Adaptive Beamforming Method and Its Application for Trans-skull Imaging of Certain Types of Head Injuries; Part I: Transmission Mode.

    Science.gov (United States)

    Shapoori, Kiyanoosh; Sadler, Jeff; Wydra, Adrian; Malyarenko, Eugene V; Sinclair, Anthony N; Maev, Roman Gr

    2015-05-01

    A new adaptive beamforming algorithm for imaging via small-aperture 1-D ultrasonic-phased arrays through composite layered structures is reported. Such structures cause acoustic phase aberration and wave refraction at undulating interfaces and can lead to significant distortion of an ultrasonic field pattern produced by conventional beamforming techniques. This distortion takes the form of defocusing the ultrasonic field transmitted through the barrier and causes loss of resolution and overall degradation of image quality. To compensate for the phase aberration and the refractional effects, we developed and examined an adaptive beamforming algorithm for small-aperture linear-phased arrays. After accurately assessing the barrier's local geometry and sound speed, the method calculates a new timing scheme to refocus the distorted beam at its original location. As a tentative application, implementation of this method for trans-skull imaging of certain types of head injuries through human skull is discussed. Simulation and laboratory results of applying the method on skull-mimicking phantoms are presented. Correction of up to 2.5 cm focal point displacement at up to 10 cm depth under our skull phantom is demonstrated. Quantitative assessment of the method in a variety of temporal focusing scenarios is also reported. Overall temporal deviation on the order of a few nanoseconds was observed between the simulated and experimental results. The single-point adaptive focusing results demonstrate strong potential of our approach for diagnostic imaging through intact human skull. The algorithms were implemented on an ultrasound advanced open-platform controlling 64 active elements on a 128-element phased array. PMID:25423646

  19. Internal Stress Monitoring of In-Service Structural Steel Members with Ultrasonic Method

    Directory of Open Access Journals (Sweden)

    Zuohua Li

    2016-03-01

    Full Text Available Internal stress in structural steel members is an important parameter for steel structures in their design, construction, and service stages. However, it is hard to measure via traditional approaches. Among the existing non-destructive testing (NDT methods, the ultrasonic method has received the most research attention. Longitudinal critically refracted (Lcr waves, which propagate parallel to the surface of the material within an effective depth, have shown great potential as an effective stress measurement approach. This paper presents a systematic non-destructive evaluation method to determine the internal stress in in-service structural steel members using Lcr waves. Based on theory of acoustoelasticity, a stress evaluation formula is derived. Factor of stress to acoustic time difference is used to describe the relationship between stress and measurable acoustic results. A testing facility is developed and used to demonstrate the performance of the proposed method. Two steel members are measured by using the proposed method and the traditional strain gauge method for verification. Parametric studies are performed on three steel members and the aluminum plate to investigate the factors that influence the testing results. The results show that the proposed method is effective and accurate for determining stress in in-service structural steel members.

  20. Advances of evolutionary computation methods and operators

    CERN Document Server

    Cuevas, Erik; Oliva Navarro, Diego Alberto

    2016-01-01

    The goal of this book is to present advances that discuss alternative Evolutionary Computation (EC) developments and non-conventional operators which have proved to be effective in the solution of several complex problems. The book has been structured so that each chapter can be read independently from the others. The book contains nine chapters with the following themes: 1) Introduction, 2) the Social Spider Optimization (SSO), 3) the States of Matter Search (SMS), 4) the collective animal behavior (CAB) algorithm, 5) the Allostatic Optimization (AO) method, 6) the Locust Search (LS) algorithm, 7) the Adaptive Population with Reduced Evaluations (APRE) method, 8) the multimodal CAB, 9) the constrained SSO method.

  1. Research Advance on Ultrasonic Aging of Wine Products%酒类产品超声陈化技术的研究进展

    Institute of Scientific and Technical Information of China (English)

    舒杰; 刘东红; 谢广发; 邹惠君

    2011-01-01

    Conventional aging of wine products has many disadvantages,such as the long length of aging time and the large cost of wine products.However,ultrasonic aging can activate the molecule of wine and accelerate the rate of reaction,so it can shorten the aging time of wine.In this article,we analyzed the mechanism of ultrasonic aging,and then summarized the research advance of ultrasonic aging in grape wine,white wine,yellow wine and juice wine.At last,we made a conclusion of ultrasonic aging and put forward new ideas.%酒类自然陈化存在时间过长、耗资大等缺点,而超声陈化可以利用空穴效应,提高酒中分子的活化能,加快反应速度,从而减短陈化时间。本文首先介绍酒类超声陈化的作用机理,综述了葡萄酒、白酒、黄酒以及果酒的超声陈化研究进展,最后,对超声陈化的状况进行总结,提出新的研究思路。

  2. A hybrid method for damage detection and quantification in advanced X-COR composite structures

    Science.gov (United States)

    Neerukatti, Rajesh Kumar; Rajadas, Abhishek; Borkowski, Luke; Chattopadhyay, Aditi; Huff, Daniel W.

    2016-04-01

    Advanced composite structures, such as foam core carbon fiber reinforced polymer composites, are increasingly being used in applications which require high strength, high in-plane and flexural stiffness, and low weight. However, the presence of in situ damage due to manufacturing defects and/or service conditions can complicate the failure mechanisms and compromise their strength and reliability. In this paper, the capability of detecting damages such as delaminations and foam-core separations in X-COR composite structures using non-destructive evaluation (NDE) and structural health monitoring (SHM) techniques is investigated. Two NDE techniques, flash thermography and low frequency ultrasonics, were used to detect and quantify the damage size and locations. Macro fiber composites (MFCs) were used as actuators and sensors to study the interaction of Lamb waves with delaminations and foam-core separations. The results indicate that both flash thermography and low frequency ultrasonics were capable of detecting damage in X-COR sandwich structures, although low frequency ultrasonic methods were capable of detecting through thickness damages more accurately than flash thermography. It was also observed that the presence of foam-core separations significantly changes the wave behavior when compared to delamination, which complicates the use of wave based SHM techniques. Further, a wave propagation model was developed to model the wave interaction with damages at different locations on the X-COR sandwich plate.

  3. Contribution of the ultrasonic simulation to the testing methods qualification process; Contribution de la modelisation ultrasonore au processus de qualification des methodes de controle

    Energy Technology Data Exchange (ETDEWEB)

    Le Ber, L.; Calmon, P. [CEA/Saclay, STA, 91 - Gif-sur-Yvette (France); Abittan, E. [Electricite de France (EDF-GDL), 93 - Saint-Denis (France)

    2001-07-01

    The CEA and EDF have started a study concerning the simulation interest in the qualification of nuclear components control by ultrasonic methods. In this framework, the simulation tools of the CEA, as CIVA, have been tested on real control. The method and the results obtained on some examples are presented. (A.L.B.)

  4. Detection of plating defects using ultrasonic and eddy current test methods

    International Nuclear Information System (INIS)

    The validity of ultrasonic and eddy current testing of austenitic platings of reactor pressure vessels was investigated in the context of a project funded by the Federal Radiation Protection Office (Bundesamt fuer Strahlenschutz). In the first phase, test specimens with natural defects were fabricated at MPA Stuttgart; in the second phase, plating defects were introduced in a MPA large-size vessel. Measurements showed that most plating defects will be detected by standard ultrasonic testing. The highest accuracy was achieved by a combination of ultrasonic and eddy current testing. (orig.)

  5. Experimental study and finite element analysis based on equivalent load method for laser ultrasonic measurement of elastic constants.

    Science.gov (United States)

    Zhan, Yu; Liu, Changsheng; Zhang, Fengpeng; Qiu, Zhaoguo

    2016-07-01

    The laser ultrasonic generation of Rayleigh surface wave and longitudinal wave in an elastic plate is studied by experiment and finite element method. In order to eliminate the measurement error and the time delay of the experimental system, the linear fitting method of experimental data is applied. The finite element analysis software ABAQUS is used to simulate the propagation of Rayleigh surface wave and longitudinal wave caused by laser excitation on a sheet metal sample surface. The equivalent load method is proposed and applied. The pulsed laser is equivalent to the surface load in time and space domain to meet the Gaussian profile. The relationship between the physical parameters of the laser and the load is established by the correction factor. The numerical solution is in good agreement with the experimental result. The simple and effective numerical and experimental methods for laser ultrasonic measurement of the elastic constants are demonstrated. PMID:27079489

  6. A time-domain finite element boundary integration method for ultrasonic nondestructive evaluation.

    Science.gov (United States)

    Shi, Fan; Choi, Wonjae; Skelton, Elizabeth A; Lowe, Michael J S; Craster, Richard V

    2014-12-01

    A 2-D and 3-D numerical modeling approach for calculating the elastic wave scattering signals from complex stress-free defects is evaluated. In this method, efficient boundary integration across the complex boundary of the defect is coupled with a time-domain finite element (FE) solver. The model is designed to simulate time-domain ultrasonic nondestructive evaluation in bulk media. This approach makes use of the hybrid concept of linking a local numerical model to compute the near-field scattering behavior and theoretical mathematical formulas for postprocessing to calculate the received signals. It minimizes the number of monitoring signals from the FE calculation so that the computation effort in postprocessing decreases significantly. In addition, by neglecting the conventional regular monitoring box, the region for FE calculation can be made smaller. In this paper, the boundary integral method is implemented in a commercial FE code, and it is validated by comparing the scattering signals with results from corresponding full FE models. The coupled method is then implemented in real inspection scenarios in both 2-D and 3-D, and the accuracy and the efficiency are demonstrated. The limitations of the proposed model and future works are also discussed. PMID:25474780

  7. A coupled finite-element, boundary-integral method for simulating ultrasonic flowmeters.

    Science.gov (United States)

    Bezdĕk, Michal; Landes, Hermann; Rieder, Alfred; Lerch, Reinhard

    2007-03-01

    Today's most popular technology of ultrasonic flow measurement is based on the transit-time principle. In this paper, a numerical simulation technique applicable to the analysis of transit-time flowmeters is presented. A flowmeter represents a large simulation problem that also requires computation of acoustic fields in moving media. For this purpose, a novel boundary integral method, the Helmholtz integral-ray tracing method (HIRM), is derived and validated. HIRM is applicable to acoustic radiation problems in arbitrary mean flows at low Mach numbers and significantly reduces the memory demands in comparison with the finite-element method (FEM). It relies on an approximate free-space Green's function which makes use of the ray tracing technique. For simulation of practical acoustic devices, a hybrid simulation scheme consisting of FEM and HIRM is proposed. The coupling of FEM and HIRM is facilitated by means of absorbing boundaries in combination with a new, reflection-free, acoustic-source formulation. Using the coupled FEM-HIRM scheme, a full three-dimensional (3-D) simulation of a complete transit-time flowmeter is performed for the first time. The obtained simulation results are in good agreement with measurements both at zero flow and under flow conditions. PMID:17375833

  8. Production of new and conventional metallic materials and their characterization by ultrasonic and metallographic methods

    International Nuclear Information System (INIS)

    The investigations of this project were realized by proposed program. As an initial material the powder metallic particle was used and other metallic materials obtained by conventional procedure in the domicile metallic industry. The metals in powder (Ti, Ni, Cu, Fe) were got from the companies MERCK and FLUKA. According to the methods of the powder metallurgy (first mixed, after that compacted and densified) the samples for need investigations were prepared. In this case (with special procedure; homogenization, pressing and sintering) new porous materials were produced, with defined geometry and with characteristic properties, most interesting as both theoretical and applied aspects. The ultrasonic and metallographic characterization and some other examination were made on this materials. The materials, steel and aluminium, were obtained in domicile factories which produced and manufactured this conventional materials. The choice of this material is selected by defined technological procedure, needed for obtaining correlation between microstructure and macroscopic properties of the examined materials. For the examination on the influence of the different concentration of the components, as a thermal and mechanical treatment, metallographic analyze in the examined materials was made. The ultrasonic investigations in previous noted materials were made in isothermal and in some special case in nonisothermal conditions. For this purpose special equipment was constructed with possibility to program changing of the temperature. From the experimental measured values of the density and velocities of ultrasound, by relationship from theory of elasticity the modulus of elasticity (E, K and G) and Poisson's ratio are determined. In this case it is possible to obtain complete information of the elastic state on the examined materials - most important characteristic in examination of the materials with shape memory effect. Finally in this project the special attention was made

  9. 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.

  10. Development of a method to characterize high-protein dairy powders using an ultrasonic flaw detector.

    Science.gov (United States)

    Hauser, M; Amamcharla, J K

    2016-02-01

    Dissolution behavior of high-protein dairy powders plays a critical role for achieving functional and nutritional characteristics of a finished food product. Current methods for evaluating powder dissolution properties are time consuming, difficult to reproduce, and subjective. Ultrasound spectroscopy is a rapid and precise method, but requires expensive equipment and skilled technicians to carry out the tests. In the present study, an ultrasonic flaw detector (UFD) was used as an economical alternative to characterize the powder dissolution properties. The objective of study was to develop a method to characterize the dissolution behavior of milk protein concentrate (MPC) using a UFD. The experimental setup included a UFD connected to a 1-MHz immersion transducer that was kept a constant distance from a reflector plate. To validate the method, 2 batches of MPC80 from a commercial manufacturer were procured and stored at 25 and 40°C for 4 wk. Focus beam reflectance measurement and solubility index were used as reference methods. Relative ultrasound velocity and ultrasound attenuation were acquired during the dissolution of MPC samples. To characterize the MPC dissolution, 4 parameters including standard deviation of relative velocity, area under the attenuation curve, and peak attenuation were extracted from ultrasound data. As the storage temperature and time increased, the area under the attenuation curve and peak height decreased, indicating a loss of solubility. The proposed UFD-based method was able to capture the changes in dissolution of MPC during storage at 25 and 40°C. It was observed that a high-quality MPC had a low standard deviation and a larger area under the attenuation curve. As the MPC aged at 40°C, the particle dispersion rate decreased and, consequently, an increase in standard deviation and reduction in area were observed. Overall, the UFD can be a low-cost method to characterize the dissolution behavior of high-protein dairy powders. PMID

  11. A method for ultrasonic quality evaluation of glass/polyester composites

    OpenAIRE

    S. Pawlak; L. Wierzbicki; G. Wróbel

    2007-01-01

    attenuation coefficient and the local fiber content in glass/polyester composites.Design/methodology/approach: Experimental data have been obtained using ultrasonic wave velocity and attenuation measurements. To determine the actual fiber content in the composites, needed to build proper relationships between considered factors, the standard destructive analysis was applied. For ultrasonic non-destructive testing, through-transmission technique was used.Findings: Experimental results have sho...

  12. Ultrasonic Method for Concentration and Particle Size Analysis in Dense Coal-water Slurry

    Science.gov (United States)

    Xue, Minghua; Su, Mingxu; Dong, Lili; Shang, Zhitao; Cai, Xiaoshu

    2007-06-01

    The concentration and particle size distribution in particulate two-phase flow are the important parameters in a wide variety of industrial areas. For the purpose of on-line characterizing dense coal-water slurry, ultrasonic methods have many advantages, such as no-dilution, real-time and no-invasion, while light-based techniques are not capable of providing information because optical methods normally require the sample to be diluted. In this paper, the modified Urick equation including temperature modification, which can be used to determine concentration from the measurement of velocity in the coal-water slurry, is evaluated on the basis of model analysis and experiments. Combined with the optimum regulation technique inverse algorithm, the particle size distribution of the coal-water slurry is obtained according to the attenuation prediction of Coupled-phase model plus Bouguer-Lambert-Beer-Law scattering model and experimental attenuation at frequencies ranges from 3MHz to 12MHz. This technique brings the possibility of using ultrasound for on-line measurement of dense slurry.

  13. A method to measure the movement of a rough plane ultrasonically by Doppler - phase shift

    Science.gov (United States)

    Kortelainen, Juha

    The Doppler effect has been used to measure the horizontal movement of a rough plane. The operational principle is based on the measurement of the phase shift of an ultrasonic wave scattered from the surface. This method has been developed for measuring the length of logs in a forest machine. Equations for the Doppler phase shift have been derived for the situation where the moving object is a single particle. Later this 'one-particle-theory' has been expanded for the situation where the moving object is a rough plane. The theory uses some simplifications and assumptions from the reality, but the results still agree well with measurements. This method has been tested by moving logs with a velocity varying from 0 to 1 m/s. The variability of measurement with different kind of logs was about 0.3 ... 2% when the movement was about one meter. The analysis of the errors and ideas to compensate them are presented in the paper.

  14. 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.

  15. Dynamic analysis of ultrasonically levitated droplet with moving particle semi-implicit and distributed point source method

    Science.gov (United States)

    Wada, Yuji; Yuge, Kohei; Nakamura, Ryohei; Tanaka, Hiroki; Nakamura, Kentaro

    2015-07-01

    Numerical analysis of an ultrasonically levitated droplet with a free surface boundary is discussed. The droplet is known to change its shape from sphere to spheroid when it is suspended in a standing wave owing to the acoustic radiation force. However, few studies on numerical simulation have been reported in association with this phenomenon including fluid dynamics inside the droplet. In this paper, coupled analysis using the distributed point source method (DPSM) and the moving particle semi-implicit (MPS) method, both of which do not require grids or meshes to handle the moving boundary with ease, is suggested. A droplet levitated in a plane standing wave field between a piston-vibrating ultrasonic transducer and a reflector is simulated with the DPSM-MPS coupled method. The dynamic change in the spheroidal shape of the droplet is successfully reproduced numerically, and the gravitational center and the change in the spheroidal aspect ratio are discussed and compared with the previous literature.

  16. Advances in Packaging Methods, Processes and Systems

    Directory of Open Access Journals (Sweden)

    Nitaigour Premchand Mahalik

    2014-10-01

    Full Text Available The food processing and packaging industry is becoming a multi-trillion dollar global business. The reason is that the recent increase in incomes in traditionally less economically developed countries has led to a rise in standards of living that includes a significantly higher consumption of packaged foods. As a result, food safety guidelines have been more stringent than ever. At the same time, the number of research and educational institutions—that is, the number of potential researchers and stakeholders—has increased in the recent past. This paper reviews recent developments in food processing and packaging (FPP, keeping in view the aforementioned advancements and bearing in mind that FPP is an interdisciplinary area in that materials, safety, systems, regulation, and supply chains play vital roles. In particular, the review covers processing and packaging principles, standards, interfaces, techniques, methods, and state-of-the-art technologies that are currently in use or in development. Recent advances such as smart packaging, non-destructive inspection methods, printing techniques, application of robotics and machineries, automation architecture, software systems and interfaces are reviewed.

  17. Comparison between sensitivities of quality control methods using ultrasonic waves, radiography and acoustic emission for the thick welded joint testing

    International Nuclear Information System (INIS)

    The testing of the thick welded joints of the nuclear industry is carried out by radiography and ultrasonics on completion of welding. When a fault is found, its repair requires a sometimes deep cut down to the position of the fault, then filling in of the cut by hand welding with a coated electrode. This very costly operation also involves the risk of causing new defects when building up by hand. Listening to the acoustic emission during the welding has been considered in order to seek the possibility of detecting defects when they appear, or soon after. The industrial use of this method would make an instant repair of the defective areas possible at less cost and with greater reliability. The study presented concerns the comparison between the results of the various non-destructive testing methods: radiography, ultrasonics and acoustic emission, for a thick welded joint in which the defects have been brought about

  18. An Adaptive 6-DOF Tracking Method by Hybrid Sensing for Ultrasonic Endoscopes

    Directory of Open Access Journals (Sweden)

    Chengyang Du

    2014-06-01

    Full Text Available In this paper, a novel hybrid sensing method for tracking an ultrasonic endoscope within the gastrointestinal (GI track is presented, and the prototype of the tracking system is also developed. We implement 6-DOF localization by sensing integration and information fusion. On the hardware level, a tri-axis gyroscope and accelerometer, and a magnetic angular rate and gravity (MARG sensor array are attached at the end of endoscopes, and three symmetric cylindrical coils are placed around patients’ abdomens. On the algorithm level, an adaptive fast quaternion convergence (AFQC algorithm is introduced to determine the orientation by fusing inertial/magnetic measurements, in which the effects of magnetic disturbance and acceleration are estimated to gain an adaptive convergence output. A simplified electro-magnetic tracking (SEMT algorithm for dimensional position is also implemented, which can easily integrate the AFQC’s results and magnetic measurements. Subsequently, the average position error is under 0.3 cm by reasonable setting, and the average orientation error is 1° without noise. If magnetic disturbance or acceleration exists, the average orientation error can be controlled to less than 3.5°.

  19. Estimation of temperature elevation generated by ultrasonic irradiation in biological tissues using the thermal wave method

    Institute of Scientific and Technical Information of China (English)

    Liu Xiao-Zhou; Zhu Yi; Zhang Fei; Gong Xiu-Fen

    2013-01-01

    In most previous models,simulation of the temperature generation in tissue is based on the Pennes bio-heat transfer equation,which implies an instantaneous thermal energy deposition in the medium.Due to the long thermal relaxation time τ (20 s-30 s) in biological tissues,the actual temperature elevation during clinical treatments could be different from the value predicted by the Pennes bioheat equation.The thermal wave model of bio-heat transfer (TWMBT) defines a thermal relaxation time to describe the tissue heating from ultrasound exposure.In this paper,COMSOL Multiphysics 3.5a,a finite element method software package,is used to simulate the temperature response in tissues based on Pennes and TWMBT equations.We further discuss different factors in the bio-heat transfer model on the influence of the temperature rising and it is found that the temperature response in tissue under ultrasound exposure is a rising process with a declining rate.The thermal relaxation time inhibits the temperature elevation at the beginning of ultrasonic heating.Besides,thermal relaxation in TWMBT leads to lower temperature estimation than that based on Pennes equation during the same period of time.The blood flow carrying heat dominates most to the decline of temperature rising rate and the influence increases with temperature rising.On the contrary,heat diffusion,which can be described by thermal conductivity,has little effect on the temperature rising.

  20. Photocatalytic studies of Ag/ZnO nanocomposite particles produced via ultrasonic spray pyrolysis method

    Energy Technology Data Exchange (ETDEWEB)

    Dermenci, Kamil Burak [Dept. of Materials Science and Engineering, Anadolu University, Eskisehir (Turkey); Dept. of Metallurgical and Materials Engineering, Istanbul Technical University, Istanbul (Turkey); Genc, Bora [Dept. of Environmental Engineering, Istanbul Technical University, Istanbul (Turkey); Ebin, Burçak [Dept. of Metallurgical and Materials Engineering, Istanbul Technical University, Istanbul (Turkey); Olmez-Hanci, Tugba [Dept. of Environmental Engineering, Istanbul Technical University, Istanbul (Turkey); Gürmen, Sebahattin, E-mail: gurmen@itu.edu.tr [Dept. of Metallurgical and Materials Engineering, Istanbul Technical University, Istanbul (Turkey)

    2014-02-15

    Highlights: • Ag/ZnO nanocomposite catalyst with a single step route is synthesized. • Methylene Blue decolorization, degradation and first order kinetics is studied. • The highest decolorization and degradation rates are 40% and 27% respectively. • The highest degradation rate coefficient is 9 × 10{sup −3} min{sup −1}. • Crystallite sizes and atomic fraction difference are important parameters. -- Abstract: Noble metal/semiconductor oxide nanocomposites have considerable interest on degradation of pollutants from textile wastewaters. Ag/ZnO, as one of the noble metal/semiconductor oxide nanocomposite, is highly efficient catalyst in textile pollutant degradation that allows irradiation wavelength towards visible light region. Ultrasonic spray pyrolysis method was used to produce spherical, homogenously distributed and submicron Ag/ZnO nanocomposite particles in one step. A water leach solution (0.05–0.2 M, Ag{sup +}:Zn{sup 2+} = 1:1) is carried by non-cost air into the reaction furnace (T = 700 °C, 800 °C and 900 °C). UV-A illumination of Methylene Blue (MB) with the presence of Ag/ZnO nanocatalysts after 60 min results up to 40% MB decolorization, 9 × 10{sup −3} min{sup −1} decolorization rate constant.

  1. Ultrasonic tissue characterization of vulnerable carotid plaque: correlation between videodensitometric method and histological examination

    Directory of Open Access Journals (Sweden)

    Cherri Jesualdo

    2006-08-01

    Full Text Available Abstract Background To establish the correlation between quantitative analysis based on B-mode ultrasound images of vulnerable carotid plaque and histological examination of the surgically removed plaque, on the basis of a videodensitometric digital texture characterization. Methods Twenty-five patients (18 males, mean age 67 ± 6.9 years admitted for carotid endarterectomy for extracranial high-grade internal carotid artery stenosis (≥ 70% luminal narrowing underwent to quantitative ultrasonic tissue characterization of carotid plaque before surgery. A computer software (Carotid Plaque Analysis Software was developed to perform the videodensitometric analysis. The patients were divided into 2 groups according to symptomatology (group I, 15 symptomatic patients; and group II, 10 patients asymptomatic. Tissue specimens were analysed for lipid, fibromuscular tissue and calcium. Results The first order statistic parameter mean gray level was able to distinguish the groups I and II (p = 0.04. The second order parameter energy also was able to distinguish the groups (p = 0,02. A histological correlation showed a tendency of mean gray level to have progressively greater values from specimens with 75% of fibrosis. Conclusion Videodensitometric computer analysis of scan images may be used to identify vulnerable and potentially unstable lipid-rich carotid plaques, which are less echogenic in density than stable or asymptomatic, more densely fibrotic plaques.

  2. Corrosion Resistance Analysis of Sintered NdFeB Magnets Using Ultrasonic-Aided EDM Method

    Science.gov (United States)

    Li, L.; Wei, X. T.; Li, Z. Y.; Cheng, X.

    2015-01-01

    Sintered neodymium-iron-boron (NdFeB) permanent magnets are widely used in many fields because of their excellent magnetic property. However, their poor corrosion resistance has been cited as a potential problem that limits their extensive application. This paper presents an experimental investigation into the improvement of surface corrosion resistance with the ultrasonic-aided electrical discharge machining (U-EDM) method. A scanning electron microscope was used to analyze the surface morphology of recast layers formed through the EDM and U-EDM processes. The chemical structure and elements of these recast layers were characterized using x-ray diffraction and energy dispersive spectroscopy. Corrosion resistance was also studied by means of potentiodynamic polarization, electrochemical impedance spectroscopy, and immersion tests in 0.5 mol/L H2SO4 solution. Experimental results show that an amorphous structure was formed in the recast layer during the EDM and U-EDM processes and that this structure could improve the corrosion resistance of sintered NdFeB magnets. Moreover, the corrosion resistance of U-EDM-treated surface was better than that of the EDM-treated surface.

  3. Resolution enhancement for ultrasonic echographic technique in non destructive testing with an adaptive deconvolution method

    International Nuclear Information System (INIS)

    The ultrasonic echographic technique has specific advantages which makes it essential in a lot of Non Destructive Testing (NDT) investigations. However, the high acoustic power necessary to propagate through highly attenuating media can only be transmitted by resonant transducers, which induces severe limitations of the resolution on the received echograms. This resolution may be improved with deconvolution methods. But one-dimensional deconvolution methods come up against problems in non destructive testing when the investigated medium is highly anisotropic and inhomogeneous (i.e. austenitic steel). Numerous deconvolution techniques are well documented in the NDT literature. But they often come from other application fields (biomedical engineering, geophysics) and we show they do not apply well to specific NDT problems: frequency-dependent attenuation and non-minimum phase of the emitted wavelet. We therefore introduce a new time-domain approach which takes into account the wavelet features. Our method solves the deconvolution problem as an estimation one and is performed in two steps: (i) A phase correction step which takes into account the phase of the wavelet and estimates a phase-corrected echogram. The phase of the wavelet is only due to the transducer and is assumed time-invariant during the propagation. (ii) A band equalization step which restores the spectral content of the ideal reflectivity. The two steps of the method are performed using fast Kalman filters which allow a significant reduction of the computational effort. Synthetic and actual results are given to prove that this is a good approach for resolution improvement in attenuating media

  4. Development of Translational Methods in Spectral Analysis of Human Infant Crying and Rat Pup Ultrasonic Vocalizations for Early Neurobehavioral Assessment

    OpenAIRE

    Philip Sanford Zeskind; McMurray, Matthew S.; Kristin Ann Garber; Juliana Miriam Neuspiel; Elizabeth Thomas Cox; Grewen, Karen M.; Mayes, Linda C.; Johns, Josephine M.

    2011-01-01

    The purpose of this article is to describe the development of translational methods by which spectrum analysis of human infant crying and rat pup ultrasonic vocalizations (USVs) can be used to assess potentially adverse effects of various prenatal conditions on early neurobehavioral development. The study of human infant crying has resulted in a rich set of measures that has long been used to assess early neurobehavioral insult due to non-optimal prenatal environments, even among seemingly he...

  5. Photocatalytic Activities of Copper Doped Cadmium Sulfide Microspheres Prepared by a Facile Ultrasonic Spray-Pyrolysis Method

    OpenAIRE

    Jinzhan Su; Tao Zhang; Yufeng Li; Yubin Chen; Maochang Liu

    2016-01-01

    Ultrasonic spray pyrolysis is a superior method for preparing and synthesizing spherical particles of metal oxide or sulfide semiconductors. Cadmium sulfide (CdS) photocatalysts with different sizes and doped-CdS with different dopants and doping levels have been synthesized to study their properties of photocatalytic hydrogen production from water. The CdS photocatalysts were characterized with scanning electron microscopy (SEM), X-ray fluorescence-spectrometry (XRF), UV-Vis absorption spect...

  6. Ultrasonic TOFD method application for steel components and welds of 10 mm wall thickness using ultrasonic flaw detector and ULTRA7 TOFD software

    International Nuclear Information System (INIS)

    Pressure Vessels inspection is carried out using complex of NDT techniques. A relatively recent technique ultrasonic NDJ is the Time-of-Flight Diffraction (TOFD,) method as an effective method for detection and sizing of flaws. One of the way inspection heavy duty steel elements and welds is to use manual TOFD technique with longitudinal waves at refracted angles of 45 to 70 degrees. Typically inspections using this method have been on steel elements and welds varying from 12 mm to 300 mm wall thickness. In this paper is presented examples of using the TOFD techniques for 10 mm wall thickness using USM 35X5 and ULTRA-7 TOFD software. This software provides TOFD inspection design (PCS, sound path, beam coverage, dead zones) and validation services. The calculations of the two dead zones are derived from relatively trigonometric equation, graphically displayed on a PC-screen and weld frame form. Using ULTRA-7 TOFD the user must move the gate at which the flaw is located on PC-screen to determine the depth of defect. The diffraction points graphically displayed in a weld frame form and analyzed using geometry calculations. (authors)

  7. Comparison of Ultrasonic and CO2 Laser Pretreatment Methods on Enzyme Digestibility of Corn Stover

    Directory of Open Access Journals (Sweden)

    Li-Li Zuo

    2012-03-01

    Full Text Available To decrease the cost of bioethanol production, biomass recalcitrance needs to be overcome so that the conversion of biomass to bioethanol becomes more efficient. CO2 laser irradiation can disrupt the lignocellulosic physical structure and reduce the average size of fiber. Analyses with Fourier transform infrared spectroscopy, specific surface area, and the microstructure of corn stover were used to elucidate the enhancement mechanism of the pretreatment process by CO2 laser irradiation. The present work demonstrated that the CO2 laser had potential to enhance the bioconversion efficiency of lignocellulosic waste to renewable bioethanol. The saccharification rate of the CO2 laser pretreatment was significantly higher than ultrasonic pretreatment, and reached 27.75% which was 1.34-fold of that of ultrasonic pretreatment. The results showed the impact of CO2 laser pretreatment on corn stover to be more effective than ultrasonic pretreatment.

  8. Ultrasonic flaw detecting device for welded portion of stab and flaw detecting method therefor

    International Nuclear Information System (INIS)

    In the present invention, flaws are detected efficiently only for the welded portion of a stab disposed to a lower end plate of a pressure vessel used in a nuclear power plant. Namely, the device of the present invention comprises (1) an ultrasonic probe disposed to a shaft of the stab of control rod drives (CRD), (2) a shaft for supporting the ultrasonic probe, (3) a driving mechanism for circumferentially rotating and further axially moving the shaft, and (4) a controlling device for controlling the equipments described above and processing data. The position of the supersonic probe is moved vertically in the axial direction while rotating the shaft and rotating the supersonic probe in the circumferential direction by the driving mechanism driven upon receiving signals from the controlling device. Flaws can be detected only for the welded portion of the CRD stab using the ultrasonic probe by repeating the operation. In addition, efficiency for the flaw detecting operation is improved. (I.S.)

  9. Study on the ultrasonic inspection method using the full matrix capture for the in service railway wheel

    International Nuclear Information System (INIS)

    The quality of wheel is especially important for the safety of high speed railway. In this paper, a new ultrasonic array inspection method, the Full Matrix Capture (FMC) has been studied and applied to the high speed railway wheel inspection, especially in the wheel web from the tread. Firstly, the principle of FMC and TFM algorithm is discussed, and then the new optimization is applied to the standard FMC; Secondly the fundamentals of optimization is described in detail and the performance is analyzed. Finally, the experiment has been built with a standard phased array block and railway wheel, and then the testing results are discussed and analyzed. It is demonstrated that this change for the ultrasonic data acquisition and image reconstruction has higher efficiency and lower cost comparing to the FMC's procedure

  10. Ultrasonic and eddy current testing of austenitic platings of reactor pressure vessels - qualification according the ENIQ method

    International Nuclear Information System (INIS)

    In the context of the research project SR2318, which received funds from the Federal Radiation Protection Office (Bundesamt fuer Strahlenschutz) and the BMU, the accuracy of eddy current and ultrasonic tests of austenitic platings on reactor pressure vessels was investigated. The results were evaluated with a view to qualification of combined ultrasonic and eddy current tests of platings and base materials on the one hand; on the other hand, a standard test procedure according to the ENIQ method (European Network of Inspection Qualification) is proposed which can serve as a basis for qualification of test procedures. Summarizing suggestions are made for updating the KTA 3201.4 regulation for recurrent inspections of platings. The results of research project SR 2351 are considered. (orig.)

  11. Non-destructive testing methods for detection of creep-induced defects by means of ultrasonic surface waves

    International Nuclear Information System (INIS)

    A method is presented for measuring the propagation velocity of surface waves in the ultrasonic frequency range. The creep-induced defect occurs predominantly at the topmost surface and leads to a minor deceleration of the ultrasonic waves in the material. With increasing penetration depth, the waves increasingly scan the material layers deeper down from the surface, which are increasingly less damaged. This indicates a smooth increase in the propagation velocity. Initial measurements at two damaged pipe bends, both after service times of more than 200.000 hours, exhibit the predicted behaviour. In both cases, the wave velocity increases at damaged sites with increasing penetration depth. The results obtained are in good agreement with metallographic examinations of the detected defect sites at the pipe bends. (orig./MM)

  12. Review and statistical analysis of the ultrasonic velocity method for estimating the porosity fraction in polycrystalline materials

    International Nuclear Information System (INIS)

    A review and statistical analysis of the ultrasonic velocity method for estimating the porosity fraction in polycrystalline materials is presented. Initially, a semi-empirical model is developed showing the origin of the linear relationship between ultrasonic velocity and porosity fraction. Then, from a compilation of data produced by many researchers, scatter plots of velocity versus percent porosity data are shown for Al2O3, MgO, porcelain-based ceramics, PZT, SiC, Si3N4, steel, tungsten, UO2,(U0.30Pu0.70)C, and YBa2Cu3O(7-x). Linear regression analysis produced predicted slope, intercept, correlation coefficient, level of significance, and confidence interval statistics for the data. Velocity values predicted from regression analysis for fully-dense materials are in good agreement with those calculated from elastic properties

  13. Mesh-free distributed point source method for modeling viscous fluid motion between disks vibrating at ultrasonic frequency.

    Science.gov (United States)

    Wada, Yuji; Kundu, Tribikram; Nakamura, Kentaro

    2014-08-01

    The distributed point source method (DPSM) is extended to model wave propagation in viscous fluids. Appropriate estimation on attenuation and boundary layer formation due to fluid viscosity is necessary for the ultrasonic devices used for acoustic streaming or ultrasonic levitation. The equations for DPSM modeling in viscous fluids are derived in this paper by decomposing the linearized viscous fluid equations into two components-dilatational and rotational components. By considering complex P- and S-wave numbers, the acoustic fields in viscous fluids can be calculated following similar calculation steps that are used for wave propagation modeling in solids. From the calculations reported the precision of DPSM is found comparable to that of the finite element method (FEM) for a fundamental ultrasonic field problem. The particle velocity parallel to the two bounding surfaces of the viscous fluid layer between two rigid plates (one in motion and one stationary) is calculated. The finite element results agree well with the DPSM results that were generated faster than the transient FEM results. PMID:25096081

  14. Determination Strength of Concrete in-Situ by Seismic Ultrasonic Method in Detecting Risky Structure

    Science.gov (United States)

    Uyanik, O.; Öziçer, S.; Sabbağ, N.

    2014-12-01

    Strength of concrete is important in the analysis of structures. Strength of concrete can be determined as destructive or non destructive. In order to determine to strength of concrete as destructive, core is taken from concrete parts of the structure and uniaxial compressive strength test is applied in the laboratory. In contrast, strength of concrete can be determined as non destructive in situ by seismic ultrasonic technique. In this study, seismic ultrasonic P wave velocity measurements. Schmidt hammer test in situ and core sampling along with uniaxial compressive test are carried out in order to determine the strength of concrete in existing structures in Bornova district of İzmir. Seismic ultrasonic P wave velocity measurements in situ were also applied on the core. The concrete strength values obtained from techniques applied in study were compared and error values are determined. By seismic ultrasonic P wave velocity measurements with error value %5 strength of concrete is determined quickly without any destruction on structures studied.

  15. 7 CFR 27.92 - Method of payment; advance deposit.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Method of payment; advance deposit. 27.92 Section 27... Micronaire § 27.92 Method of payment; advance deposit. Any payment or advance deposit under this subpart...,” and may not be made in cash except in cases where the total payment or deposit does not exceed...

  16. Static modulus of elasticity of concrete measured by the ultrasonic method

    Directory of Open Access Journals (Sweden)

    Sena Rodrigues, S.

    2003-12-01

    Full Text Available Lately, a huge number of accidents caused by problems found in the durability of concrete structures due to inappropriate project design, lack of control of quality during the project s execution, inadequate maintenance practices and an aggressive environment has been reported. This finding has required from the professionals constant inspections and evaluations of the real conditions of all concrete structures. In order to perform those inspections, one should know not only the elastic modulus to analyze the concrete structural behaviour but also to investigate its performance, since the strains may yield cracks able to compromise the durability- of structures. Non-destructive testing techniques, particularly the ultrasonic testing, are performed to evaluate and determine the quality of a concrete structure or element. Currently, such essays have been widely researched and analyzed all over the world because they enable the examination of structures without damaging them. The purpose of the present study was to correlate the ultrasonic pulse velocity and the elastic modulus of several concrete specimens molded with a range of water-cement ratios, different kinds of aggregates and curing methods. All the concrete specimens were tested in different ages to determine the pulse velocity and the static modulus of elasticity standardized according to KBR 8522, through mechanical extensometers, electrical strain gauge and LVTD inductive transducer.

    Recientemente se ha registrado un gran número de accidentes causados por problemas relacionados con la durabilidad de las estructuras de hormigón y debidos a un inadecuado proyecto de diseño, ausencia de control de calidad durante la ejecución del proyecto, prácticas inadecuadas de construcción y un ambiente agresivo. Este hallazgo ha dado lugar a que los ingenieros realicen constantes inspecciones y evaluaciones de la condición real de todas las estructuras de hormigón. Para llevar a cabo

  17. Ultrasonic assisted-ECAP.

    Science.gov (United States)

    Djavanroodi, F; Ahmadian, H; Koohkan, K; Naseri, R

    2013-08-01

    Equal channel angular pressing (ECAP) is one of the most prominent procedures for achieving ultra-fine grain (UFG) structures among the various severe plastic deformation (SPD) techniques. In this study, the effect of ultrasonic vibration on deformation behavior of commercial pure aluminum in the ECAP process is analyzed successfully using three dimensional (3D) by finite element methods (FEMs). The investigation includes the effects of die geometry, billet length, friction factor, ram speed, ultrasonic amplitude and ultrasonic frequency. Conventional as well as ultrasonic ECAP has been performed on aluminium 1070 alloy and the obtained data were used for validating simulations. It is observed that a 13% reduction in the average force was achieved when ultrasonic vibration with amplitude of 2.5 μm at 20 kHz is applied. Also, further reduction in ECAP forming forces are obtained with increase of vibration amplitude, vibration frequency, friction factor, billet length and die channel angle. PMID:23523093

  18. Ultrasonic assisted-ECAP.

    Science.gov (United States)

    Djavanroodi, F; Ahmadian, H; Koohkan, K; Naseri, R

    2013-08-01

    Equal channel angular pressing (ECAP) is one of the most prominent procedures for achieving ultra-fine grain (UFG) structures among the various severe plastic deformation (SPD) techniques. In this study, the effect of ultrasonic vibration on deformation behavior of commercial pure aluminum in the ECAP process is analyzed successfully using three dimensional (3D) by finite element methods (FEMs). The investigation includes the effects of die geometry, billet length, friction factor, ram speed, ultrasonic amplitude and ultrasonic frequency. Conventional as well as ultrasonic ECAP has been performed on aluminium 1070 alloy and the obtained data were used for validating simulations. It is observed that a 13% reduction in the average force was achieved when ultrasonic vibration with amplitude of 2.5 μm at 20 kHz is applied. Also, further reduction in ECAP forming forces are obtained with increase of vibration amplitude, vibration frequency, friction factor, billet length and die channel angle.

  19. Advanced continuous cultivation methods for systems microbiology.

    Science.gov (United States)

    Adamberg, Kaarel; Valgepea, Kaspar; Vilu, Raivo

    2015-09-01

    Increasing the throughput of systems biology-based experimental characterization of in silico-designed strains has great potential for accelerating the development of cell factories. For this, analysis of metabolism in the steady state is essential as only this enables the unequivocal definition of the physiological state of cells, which is needed for the complete description and in silico reconstruction of their phenotypes. In this review, we show that for a systems microbiology approach, high-resolution characterization of metabolism in the steady state--growth space analysis (GSA)--can be achieved by using advanced continuous cultivation methods termed changestats. In changestats, an environmental parameter is continuously changed at a constant rate within one experiment whilst maintaining cells in the physiological steady state similar to chemostats. This increases the resolution and throughput of GSA compared with chemostats, and, moreover, enables following of the dynamics of metabolism and detection of metabolic switch-points and optimal growth conditions. We also describe the concept, challenge and necessary criteria of the systematic analysis of steady-state metabolism. Finally, we propose that such systematic characterization of the steady-state growth space of cells using changestats has value not only for fundamental studies of metabolism, but also for systems biology-based metabolic engineering of cell factories.

  20. Advanced continuous cultivation methods for systems microbiology.

    Science.gov (United States)

    Adamberg, Kaarel; Valgepea, Kaspar; Vilu, Raivo

    2015-09-01

    Increasing the throughput of systems biology-based experimental characterization of in silico-designed strains has great potential for accelerating the development of cell factories. For this, analysis of metabolism in the steady state is essential as only this enables the unequivocal definition of the physiological state of cells, which is needed for the complete description and in silico reconstruction of their phenotypes. In this review, we show that for a systems microbiology approach, high-resolution characterization of metabolism in the steady state--growth space analysis (GSA)--can be achieved by using advanced continuous cultivation methods termed changestats. In changestats, an environmental parameter is continuously changed at a constant rate within one experiment whilst maintaining cells in the physiological steady state similar to chemostats. This increases the resolution and throughput of GSA compared with chemostats, and, moreover, enables following of the dynamics of metabolism and detection of metabolic switch-points and optimal growth conditions. We also describe the concept, challenge and necessary criteria of the systematic analysis of steady-state metabolism. Finally, we propose that such systematic characterization of the steady-state growth space of cells using changestats has value not only for fundamental studies of metabolism, but also for systems biology-based metabolic engineering of cell factories. PMID:26220303

  1. 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.

  2. Porous material characterization--ultrasonic method for estimation of tortuosity and characteristic length using a barometric chamber.

    Science.gov (United States)

    Moussatov, A; Ayrault, C; Castagnède, B

    2001-04-01

    An ultrasonic method of acoustic parameter evaluation for porous materials saturated by air (or any other gas) is discussed. The method is based on the evolution of speed of sound and the attenuation inside the material when the static pressure of the gas saturating the material is changed. Asymptotic development of the equivalent fluid model of Johnson-Allard is used for analytical description. The method allows an estimation of three essential parameters of the model: the tortuosity, and the viscous and thermal characteristic lengths. Both characteristic lengths are estimated individually by assuming a given ratio between them. Tests are performed with industrial plastic foams and granular substances (glass beads, sea sand) over a gas pressure range from 0.2 to 6 bars at the frequencies 30-600 kHz. The present technique has a number of distinct advantages over the conventional ultrasonic approach: operation at a single frequency, improved signal-to-noise ratio, possibility of saturation the porous media by different gases. In the case when scattering phenomena occur, the present method permits a separate analysis of scattering losses and viscothermal losses. An analytical description of the method is followed by a presentation of the set-up and the measurement procedure. Experimental results and perspectives are discussed. PMID:11350000

  3. An absolute method for determination of misalignment of an immersion ultrasonic transducer.

    Science.gov (United States)

    Narayanan, M M; Singh, Narender; Kumar, Anish; Babu Rao, C; Jayakumar, T

    2014-12-01

    An absolute methodology has been developed for quantification of misalignment of an ultrasonic transducer using a corner-cube retroreflector. The amplitude based and the time of flight (TOF) based C-scans of the reflector are obtained for various misalignments of the transducer. At zero degree orientation of the transducer, the vertical positions of the maximum amplitude and the minimum TOF in the C-scan coincide. At any other orientation of the transducer with the horizontal plane, there is a vertical shift in the position of the maximum amplitude with respect to the minimum TOF. The position of the minimum (TOF) remains the same irrespective of the orientation of the transducer and hence is used as a reference for any misalignment of the transducer. With the measurement of the vertical shift and the horizontal distance between the transducer and the vertex of the reflector, the misalignment of the transducer is quantified. Based on the methodology developed in the present study, retroreflectors are placed in the Indian 500MWe Prototype Fast Breeder Reactor for assessment of the orientation of the ultrasonic transducer prior to the under-sodium ultrasonic scanning for detection of any protrusion of the subassemblies. PMID:25041979

  4. On-machine characterization of moving paper using a photo-emf laser ultrasonics method

    Science.gov (United States)

    Pouet, Bruno F.; Lafond, Emmanuel F.; Pufahl, Brian; Bacher, Gerald D.; Brodeur, Pierre H.; Klein, Marvin B.

    1999-02-01

    Stiffness properties of paper materials can readily be characterized in the laboratory using conventional ultrasonic techniques. For on-line inspection on a paper machine, due to the high translation velocity and the somewhat fragile nature of the moving paper web, contact ultrasonic techniques using piezoelectric transducers are of limited use. To overcome this limitation, non-contact laser- based ultrasonic techniques can be used. Due to the rough surface of the paper, the reflected light is composed of many speckles. For efficient detection, the receiver must be able to process as many speckles as possible. Adaptive receivers using the photorefractive or photo-emf effects are characterized by a large etendue, and thus, are well suited for detection on paper and paperboard. Moreover, the translation velocity of the moving web implies that the detection system must adapt extremely quickly to the changing speckle pattern. In this work, a photo-emf receiver was used to detect Lamb waves excited using a pulsed Nd:YAG laser in moving paper. Experiments were performed using a variable-speed web simulator at speeds much higher than 1 m.s-1. Results corresponding to various translation speeds are shown, demonstrating the feasibility of laser- based ultrasound for on-machine inspection of paper and paperboard during production.

  5. Synthesis of Vanadium Oxide Nano tubes From V2O5 Gel Via An Ultrasonic and Hydrothermal Method

    International Nuclear Information System (INIS)

    Vanadium oxide nano tubes have been prepared by using two types of amine, hexadecenylamine and hexylamine. The amines and V2O5.nH2O gel were combined via ultrasonic method for better mixing and distribution. This was followed by one- step hydrothermal treatment between 1 to 7 days. The main objective of the study is to produce good quality VOX-NTS at the fastest synthesis time. Well-developed vanadium oxide nano tubes using hexadecenylamine template were obtained with just two days of hydrothermal treatment. (author)

  6. Measuring technique of liner thickness of zirconium-lined zircaloy-2 tube-shell using ultrasonic method

    International Nuclear Information System (INIS)

    In order to control the liner thickness of a Zr-lined Zircaloy fuel cladding tube, it is very important to know accurately the liner thickness of the original tube from which it was rolled. A new technique was developed using an ultrasonic method to measure liner thickness. It measures at every point on the circumference over the 4-meter length of the original tube in only 3 minutes. The error of measurement is less than 50 microns. The technique has been in use on the production line of our Chofu-Kita Plant. (author)

  7. Structural health monitoring ultrasonic thickness measurement accuracy and reliability of various time-of-flight calculation methods

    Science.gov (United States)

    Eason, Thomas J.; Bond, Leonard J.; Lozev, Mark G.

    2016-02-01

    The accuracy, precision, and reliability of ultrasonic thickness structural health monitoring systems are discussed in-cluding the influence of systematic and environmental factors. To quantify some of these factors, a compression wave ultrasonic thickness structural health monitoring experiment is conducted on a flat calibration block at ambient temperature with forty four thin-film sol-gel transducers and various time-of-flight thickness calculation methods. As an initial calibration, the voltage response signals from each sensor are used to determine the common material velocity as well as the signal offset unique to each calculation method. Next, the measurement precision of the thickness error of each method is determined with a proposed weighted censored relative maximum likelihood analysis technique incorporating the propagation of asymmetric measurement uncertainty. The results are presented as upper and lower confidence limits analogous to the a90/95 terminology used in industry recognized Probability-of-Detection assessments. Future work is proposed to apply the statistical analysis technique to quantify measurement precision of various thickness calculation methods under different environmental conditions such as high temperature, rough back-wall surface, and system degradation with an intended application to monitor naphthenic acid corrosion in oil refineries.

  8. Advanced Aqueous Phase Catalyst Development using Combinatorial Methods Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Combinatorial methods are proposed to develop advanced Aqueous Oxidation Catalysts (AOCs) with the capability to mineralize organic contaminants present in...

  9. CoSn-graphite electrode material prepared by using the polyol method and high-intensity ultrasonication

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Jose R. [Laboratorio de Quimica Inorganica, Universidad de Cordoba, Edificio C3, Campus de Rabanales, 14071 Cordoba (Spain); Alcantara, Ricardo, E-mail: iq2alror@uco.es [Laboratorio de Quimica Inorganica, Universidad de Cordoba, Edificio C3, Campus de Rabanales, 14071 Cordoba (Spain); Nacimiento, Francisco; Tirado, Jose L. [Laboratorio de Quimica Inorganica, Universidad de Cordoba, Edificio C3, Campus de Rabanales, 14071 Cordoba (Spain)

    2011-11-30

    Highlights: > New anode materials are prepared by combined polyol and ultrasonication methods. > Highly-dispersed, amorphous nano-CoSn/ultrathin graphite composites can be obtained. > Ultrasonication under Ar-flow and LiPAA-binder leads to high Coulombic efficiency. - Abstract: Composite electrode materials containing nanoparticles of nearly amorphous CoSn and ultrathin layers of graphite are prepared here. For this purpose, Sn(II) and Co(II) ions in tetraethyleneglycol are reduced with NaBH{sub 4} in the presence of ball-milled graphite while high-intensity ultrasonication is continuously applied. The followed preparative route is a combination of the polyol and sonochemical methods. The observed capacity value for CoSn-ball milled graphite is over 400 mAh/g after 40 cycles (this is superior to graphite). The good electrochemical cycling behavior is connected to the small particle size of CoSn, the low crystallinity of CoSn and the dispersion of the CoSn particles in an optimized carbon matrix. The selected binder (polyvinylidene fluoride or lithium polyacrylate) also can contribute to improve the cycling behavior. The low electrochemical efficiency, particularly in the first cycles, may be related to the spontaneous oxidation of the metallic particles surface and irreversible electrolyte consumption. The use of inert atmosphere (Ar-flow) results in a decrease of the tin oxide content, as determined by using {sup 119}Sn Moessbauer spectroscopy, an increase of the initial electrochemical efficiency up to a maximum of 90.4%, and higher capacities (507 mAh/g after 40 cycles).

  10. Study of different ultrasonic focusing methods applied to non destructive testing; Etude de differentes methodes de focalisation ultrasonore appliquees au controle non destructif

    Energy Technology Data Exchange (ETDEWEB)

    El Amrani, M.

    1995-11-17

    The work presented in this thesis concerns the study of different ultrasonic focusing techniques applied to Nondestructive Testing (mechanical focusing and electronic focusing) and compares their capabilities. We have developed a model to predict the ultrasonic field radiated into a solid by water-coupled transducers. The model is based upon the Rayleigh integral formulation, modified to take account the refraction at the liquid-solid interface. The model has been validated by numerous experiments in various configurations. Running this model and the associated software, we have developed new methods to optimize focused transducers and studied the characteristics of the beam generated by transducers using various focusing techniques. (author). 120 refs., 95 figs., 4 appends.

  11. Ultrasonic inspection technology development and search units design examples of practical applications

    CERN Document Server

    Brook, Mark V

    2012-01-01

    "Ultrasonic testing is a relatively new branch of science and industry. The development of ultrasonic testing started in the late 1920s. At the beginning, the fundamentals of this method were borrowed from basic physics, geometrical and wave optics, acoustics and seismology. Later it became clear that some of these theories and calculation methods could not always explain the phenomena observed in many specific cases of ultrasonic testing. Without knowing the nuances of the ultrasonic wave propagation in the test object it is impossible to design effective inspection technique and search units for it realization. This book clarifies the theoretical differences of ultrasonics from the other wave propagation theories presenting both basics of physics in the wave propagation, elementary mathematic and advanced practical applications. Almost every specific technique presented in this book is proofed by actual experimental data and examples of calculations"--

  12. Why Video? How Technology Advances Method

    Science.gov (United States)

    Downing, Martin J., Jr.

    2008-01-01

    This paper reports on the use of video to enhance qualitative research. Advances in technology have improved our ability to capture lived experiences through visual means. I reflect on my previous work with individuals living with HIV/AIDS, the results of which are described in another paper, to evaluate the effectiveness of video as a medium that…

  13. Ultrasonic method for measuring water holdup of low velocity and high-water-cut oil-water two-phasefl ow

    Institute of Scientific and Technical Information of China (English)

    Zhao An; Han Yun-Feng; Ren Ying-Yu; Zhai Lu-Sheng; Jin Ning-De

    2016-01-01

    Oil reservoirs with low permeability and porosity that are in the middle and late exploitation periods in China’s onshore oilfi elds are mostly in the high-water-cut production stage. This stage is associated with severely non-uniform local-velocity flow profiles and dispersed-phase concentration (of oil droplets) in oil-water two-phase flow, which makes it diffi cult to measure water holdup in oil wells. In this study, we use an ultrasonic method based on a transmission-type sensor in oil-water two-phase flow to measure water holdup in low-velocity and high water-cut conditions. First, we optimize the excitation frequency of the ultrasonic sensor by calculating the sensitivity of the ultrasonicfi eld using thefi nite element method for multiphysics coupling. Then we calculate the change trend of sound pressure level attenuation ratio with the increase in oil holdup to verify the feasibility of the employed diameter for the ultrasonic sensor. Based on the results, we then investigate the effects of oil-droplet diameter and distribution on the ultrasonicfi eld. To further understand the measurement characteristics of the ultrasonic sensor, we perform a flow loop test on vertical upward oil-water two-phasefl ow and measure the responses of the optimized ultrasonic sensor. The results show that the ultrasonic sensor yields poor resolution for a dispersed oil slug in waterfl ow (D OS/Wfl ow), but the resolution is favorable for dispersed oil in waterfl ow (D O/Wfl ow) and veryfi ne dispersed oil in waterfl ow (VFD O/Wfl ow). This research demonstrates the potential application of a pulsed-transmission ultrasonic method for measuring the fraction of individual components in oil-water two-phasefl ow with a low mixture velocity and high water cut.

  14. 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

  15. The quality evaluation of the end-plate welds and brazed joints for CANDU nuclear fuel by an ultrasonic imaging method

    International Nuclear Information System (INIS)

    This paper describes a method for the quality evaluation of spot welds and brazed joints by analysing ultrasonic images (C-scan). A present, the quality control for these joints is made by destructive methods. The authors present the most frequent types of flaw met in their investigations. They have attempted to obtain a dependence of torsion moment, measured by a destructive method against the polar inertia moment, obtained from parameters measured on ultrasound images. The ultrasonic images were analysed off-line using a dedicated software. (author)

  16. Photocatalytic Activities of Copper Doped Cadmium Sulfide Microspheres Prepared by a Facile Ultrasonic Spray-Pyrolysis Method.

    Science.gov (United States)

    Su, Jinzhan; Zhang, Tao; Li, Yufeng; Chen, Yubin; Liu, Maochang

    2016-01-01

    Ultrasonic spray pyrolysis is a superior method for preparing and synthesizing spherical particles of metal oxide or sulfide semiconductors. Cadmium sulfide (CdS) photocatalysts with different sizes and doped-CdS with different dopants and doping levels have been synthesized to study their properties of photocatalytic hydrogen production from water. The CdS photocatalysts were characterized with scanning electron microscopy (SEM), X-ray fluorescence-spectrometry (XRF), UV-Vis absorption spectra and X-ray diffraction (XRD) to study their morphological and optical properties. The sizes of the prepared CdS particles were found to be proportional to the concentration of the metal nitrates in the solution. The CdS photocatalyst with smaller size showed a better photocatalytic activity. In addition, Cu doped CdS were also deposited and their photocatalytic activities were also investigated. Decreased bandgaps of CdS synthesized with this method were found and could be due to high density surface defects originated from Cd vacancies. Incorporating the Cu elements increased the bandgap by taking the position of Cd vacancies and reducing the surface defect states. The optimal Cu-doped level was found to be 0.5 mol % toward hydrogen evolution from aqueous media in the presence of sacrificial electron donors (Na₂S and Na₂SO₃) at a pH of 13.2. This study demonstrated that ultrasonic spray pyrolysis is a feasible approach for large-scale photocatalyst synthesis and corresponding doping modification. PMID:27314320

  17. Photocatalytic Activities of Copper Doped Cadmium Sulfide Microspheres Prepared by a Facile Ultrasonic Spray-Pyrolysis Method

    Directory of Open Access Journals (Sweden)

    Jinzhan Su

    2016-06-01

    Full Text Available Ultrasonic spray pyrolysis is a superior method for preparing and synthesizing spherical particles of metal oxide or sulfide semiconductors. Cadmium sulfide (CdS photocatalysts with different sizes and doped-CdS with different dopants and doping levels have been synthesized to study their properties of photocatalytic hydrogen production from water. The CdS photocatalysts were characterized with scanning electron microscopy (SEM, X-ray fluorescence-spectrometry (XRF, UV-Vis absorption spectra and X-ray diffraction (XRD to study their morphological and optical properties. The sizes of the prepared CdS particles were found to be proportional to the concentration of the metal nitrates in the solution. The CdS photocatalyst with smaller size showed a better photocatalytic activity. In addition, Cu doped CdS were also deposited and their photocatalytic activities were also investigated. Decreased bandgaps of CdS synthesized with this method were found and could be due to high density surface defects originated from Cd vacancies. Incorporating the Cu elements increased the bandgap by taking the position of Cd vacancies and reducing the surface defect states. The optimal Cu-doped level was found to be 0.5 mol % toward hydrogen evolution from aqueous media in the presence of sacrificial electron donors (Na2S and Na2SO3 at a pH of 13.2. This study demonstrated that ultrasonic spray pyrolysis is a feasible approach for large-scale photocatalyst synthesis and corresponding doping modification.

  18. An Ultrasonic Sensor System Based on a Two-Dimensional State Method for Highway Vehicle Violation Detection Applications

    Science.gov (United States)

    Liu, Jun; Han, Jiuqiang; Lv, Hongqiang; Li, Bing

    2015-01-01

    With the continuing growth of highway construction and vehicle use expansion all over the world, highway vehicle traffic rule violation (TRV) detection has become more and more important so as to avoid traffic accidents and injuries in intelligent transportation systems (ITS) and vehicular ad hoc networks (VANETs). Since very few works have contributed to solve the TRV detection problem by moving vehicle measurements and surveillance devices, this paper develops a novel parallel ultrasonic sensor system that can be used to identify the TRV behavior of a host vehicle in real-time. Then a two-dimensional state method is proposed, utilizing the spacial state and time sequential states from the data of two parallel ultrasonic sensors to detect and count the highway vehicle violations. Finally, the theoretical TRV identification probability is analyzed, and actual experiments are conducted on different highway segments with various driving speeds, which indicates that the identification accuracy of the proposed method can reach about 90.97%. PMID:25894940

  19. An Ultrasonic Sensor System Based on a Two-Dimensional State Method for Highway Vehicle Violation Detection Applications

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2015-04-01

    Full Text Available With the continuing growth of highway construction and vehicle use expansion all over the world, highway vehicle traffic rule violation (TRV detection has become more and more important so as to avoid traffic accidents and injuries in intelligent transportation systems (ITS and vehicular ad hoc networks (VANETs. Since very few works have contributed to solve the TRV detection problem by moving vehicle measurements and surveillance devices, this paper develops a novel parallel ultrasonic sensor system that can be used to identify the TRV behavior of a host vehicle in real-time. Then a two-dimensional state method is proposed, utilizing the spacial state and time sequential states from the data of two parallel ultrasonic sensors to detect and count the highway vehicle violations. Finally, the theoretical TRV identification probability is analyzed, and actual experiments are conducted on different highway segments with various driving speeds, which indicates that the identification accuracy of the proposed method can reach about 90.97%.

  20. An ultrasonic sensor system based on a two-dimensional state method for highway vehicle violation detection applications.

    Science.gov (United States)

    Liu, Jun; Han, Jiuqiang; Lv, Hongqiang; Li, Bing

    2015-01-01

    With the continuing growth of highway construction and vehicle use expansion all over the world, highway vehicle traffic rule violation (TRV) detection has become more and more important so as to avoid traffic accidents and injuries in intelligent transportation systems (ITS) and vehicular ad hoc networks (VANETs). Since very few works have contributed to solve the TRV detection problem by moving vehicle measurements and surveillance devices, this paper develops a novel parallel ultrasonic sensor system that can be used to identify the TRV behavior of a host vehicle in real-time. Then a two-dimensional state method is proposed, utilizing the spacial state and time sequential states from the data of two parallel ultrasonic sensors to detect and count the highway vehicle violations. Finally, the theoretical TRV identification probability is analyzed, and actual experiments are conducted on different highway segments with various driving speeds, which indicates that the identification accuracy of the proposed method can reach about 90.97%. PMID:25894940

  1. Inverse method for the determination of elastic properties of coating layers by the surface ultrasonic waves

    Institute of Scientific and Technical Information of China (English)

    CHANG Jun; YANG Zhen; XU Jin-quan

    2005-01-01

    As the coated materials are widely applied in engineering, estimation of the elastic properties of coating layers is of great practical importance. This paper presents an inversion algorithm for determining the elastic properties of coating layers from the given velocity dispersion of surface ultrasonic waves. Based on the dispersive equation of surface waves in layered half space,an objective function dependent on coating material parameters is introduced. The density and wave velocities, which make the object function minimum, are taken as the inversion results. Inverse analyses of two parameters (longitudinal and transverse velocities) and three parameters (the density, longitudinal and transverse velocities) of the coating layer were made.

  2. Study of Estimation Method for Unsteady Inflow Velocity in Two-Dimensional Ultrasonic-Measurement-Integrated Blood Flow Simulation.

    Science.gov (United States)

    Kadowaki, Hiroko; Hayase, Toshiyuki; Funamoto, Kenichi; Taniguchi, Nobuyuki

    2016-02-01

    Information on hemodynamics is essential for elucidation of mechanisms and development of novel diagnostic methods for circulatory diseases. Two-dimensional ultrasonic-measurement-integrated (2D-UMI) simulation can correctly reproduce an intravascular blood flow field and hemodynamics by feeding back an ultrasonic measurement to the numerical blood flow simulation. In this method, it is critically important to give the correct cross-sectional average inflow velocity (inflow velocity) as the boundary condition. However, systematic study has not been done on the relative validity and effectiveness of existing inflow velocity estimation methods for various target flow fields. The aim of this study was to examine the existing methods systematically and to establish a method to accurately estimate inflow velocities for various vessel geometries and flow conditions in 2D-UMI simulations. A numerical experiment was performed for 2D-UMI simulation of blood flow models in a straight vessel with inflow velocity profiles symmetric and asymmetric to the vessel axis using existing evaluation functions based on Doppler velocity error for the inflow velocity estimation. As a result, it was clarified that a significantly large estimation error occurs in the asymmetric flow due to a nonfeedback domain near the downstream end of the calculation domain. Hence, a new inflow velocity estimation method of 2D-UMI simulation is proposed in which the feedback and evaluation domains are extended to the downstream end. Further numerical experiments of 2D-UMI simulation for two realistic vessel geometries of a healthy blood vessel and a stenosed one confirmed the effectiveness of the proposed method. PMID:26241967

  3. Deconvolution algorithms applied in ultrasonics; Methodes de deconvolution en echographie ultrasonore

    Energy Technology Data Exchange (ETDEWEB)

    Perrot, P.

    1993-12-01

    In a complete system of acquisition and processing of ultrasonic signals, it is often necessary at one stage to use some processing tools to get rid of the influence of the different elements of that system. By that means, the final quality of the signals in terms of resolution is improved. There are two main characteristics of ultrasonic signals which make this task difficult. Firstly, the signals generated by transducers are very often non-minimum phase. The classical deconvolution algorithms are unable to deal with such characteristics. Secondly, depending on the medium, the shape of the propagating pulse is evolving. The spatial invariance assumption often used in classical deconvolution algorithms is rarely valid. Many classical algorithms, parametric and non-parametric, have been investigated: the Wiener-type, the adaptive predictive techniques, the Oldenburg technique in the frequency domain, the minimum variance deconvolution. All the algorithms have been firstly tested on simulated data. One specific experimental set-up has also been analysed. Simulated and real data has been produced. This set-up demonstrated the interest in applying deconvolution, in terms of the achieved resolution. (author). 32 figs., 29 refs.

  4. Influence enhancement effect of bi-frequency ultrasonic irradiation by TA fluorescence method

    Institute of Scientific and Technical Information of China (English)

    FAN Xinnan; ZHU Changping; FENG Ruo; WANG Yuming; He Shichuan

    2004-01-01

    Based on a previous research of cavitation effect under bi-frequency ultrasound irradiation, this paper studies bi-frequency irradiations with similar experimental settings. The additional irradiation sources with frequencies of 1.04MHz, 0.8MHz and 1.7MHz are individually combined with the main ultrasonic irradiation source with frequency of 28kHz to form bi-frequency ultrasonic irradiation. The intensity of 28kHz irradiation was fixed at 12.5W/cm2, while the intensity of the ultrasound at the other three frequencies is varied from1 W/cm2 to 18 W/cm2. It turns out that under the influence of the bi-frequency irradiation, the fluorescence intensity is obviously greater than the sum of those at individual frequencies. So the frequency of the additional sonication strikingly influences the fluorescence enhancement effect. For example, the fluorescence enhancement effect of 1.04MHz is stronger than that of 1.7MHz, and the enhancement effect of 0.8MHz is further stronger than that of 1.04MHz. Under the sonic intensity of 7.9W/cm2, the fluorescence intensity of 1.04MHz is approximately twice that of 1.7MHz while the fluorescence intensity of 0.8MHz is approximately 1.5 times that of 1.04MHz.

  5. Advanced Methods of Biomedical Signal Processing

    CERN Document Server

    Cerutti, Sergio

    2011-01-01

    This book grew out of the IEEE-EMBS Summer Schools on Biomedical Signal Processing, which have been held annually since 2002 to provide the participants state-of-the-art knowledge on emerging areas in biomedical engineering. Prominent experts in the areas of biomedical signal processing, biomedical data treatment, medicine, signal processing, system biology, and applied physiology introduce novel techniques and algorithms as well as their clinical or physiological applications. The book provides an overview of a compelling group of advanced biomedical signal processing techniques, such as mult

  6. 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.

  7. Advanced electromagnetic methods for aerospace vehicles

    Science.gov (United States)

    Balanis, Constantine A.; El-Sharawy, El-Budawy; Hashemi-Yeganeh, Shahrokh; Aberle, James T.; Birtcher, Craig R.

    1991-01-01

    The Advanced Helicopter Electromagnetics is centered on issues that advance technology related to helicopter electromagnetics. Progress was made on three major topics: composite materials; precipitation static corona discharge; and antenna technology. In composite materials, the research has focused on the measurements of their electrical properties, and the modeling of material discontinuities and their effect on the radiation pattern of antennas mounted on or near material surfaces. The electrical properties were used to model antenna performance when mounted on composite materials. Since helicopter platforms include several antenna systems at VHF and UHF bands, measuring techniques are being explored that can be used to measure the properties at these bands. The effort on corona discharge and precipitation static was directed toward the development of a new two dimensional Voltage Finite Difference Time Domain computer program. Results indicate the feasibility of using potentials for simulating electromagnetic problems in the cases where potentials become primary sources. In antenna technology the focus was on Polarization Diverse Conformal Microstrip Antennas, Cavity Backed Slot Antennas, and Varactor Tuned Circular Patch Antennas. Numerical codes were developed for the analysis of two probe fed rectangular and circular microstrip patch antennas fed by resistive and reactive power divider networks.

  8. Recent advances in boundary element methods

    CERN Document Server

    Manolis, GD

    2009-01-01

    Addresses the needs of the computational mechanics research community in terms of information on boundary integral equation-based methods and techniques applied to a variety of fields. This book collects both original and review articles on contemporary Boundary Element Methods (BEM) as well as on the Mesh Reduction Methods (MRM).

  9. Ultrasonic Characterization of Aerospace Composites

    Science.gov (United States)

    Leckey, Cara; Johnston, Patrick; Haldren, Harold; Perey, Daniel

    2015-01-01

    Composite materials have seen an increased use in aerospace in recent years and it is expected that this trend will continue due to the benefits of reduced weight, increased strength, and other factors. Ongoing work at NASA involves the investigation of the large-scale use of composites for spacecraft structures (SLS components, Orion Composite Crew Module, etc). NASA is also involved in work to enable the use of composites in advanced aircraft structures through the Advanced Composites Project (ACP). In both areas (space and aeronautics) there is a need for new nondestructive evaluation and materials characterization techniques that are appropriate for characterizing composite materials. This paper will present an overview of NASA's needs for characterizing aerospace composites, including a description of planned and ongoing work under ACP for the detection of composite defects such as fiber waviness, reduced bond strength, delamination damage, and microcracking. The research approaches include investigation of angle array, guided wave, and phase sensitive ultrasonic methods. The use of ultrasonic simulation tools for optimizing and developing methods will also be discussed.

  10. Catalytic Methods in Asymmetric Synthesis Advanced Materials, Techniques, and Applications

    CERN Document Server

    Gruttadauria, Michelangelo

    2011-01-01

    This book covers advances in the methods of catalytic asymmetric synthesis and their applications. Coverage moves from new materials and technologies to homogeneous metal-free catalysts and homogeneous metal catalysts. The applications of several methodologies for the synthesis of biologically active molecules are discussed. Part I addresses recent advances in new materials and technologies such as supported catalysts, supports, self-supported catalysts, chiral ionic liquids, supercritical fluids, flow reactors and microwaves related to asymmetric catalysis. Part II covers advances and milesto

  11. Mobile ultrasonic testing in pipes

    International Nuclear Information System (INIS)

    The paper deals with the development of the ultrasonic test method, in particular with the functioning of the impulse reflection method which is used for weld testing and wall thickness measurement in pipeline construction. The paper closes on a few remarks on ultrasonic testing in plastic tubes and some other special testing problems. (RW)

  12. Ultrasonic Defect Characterization in Heavy Rotor Forgings by Means of the Synthetic Aperture Focusing Technique and Optimization Methods.

    Science.gov (United States)

    Fendt, Karl T; Mooshofer, Hubert; Rupitsch, Stefan J; Ermert, Helmut

    2016-06-01

    Ultrasonic nondestructive testing of steel forgings aims at the detection and classification of material inhomogeneities to ensure the components fitness for use. Due to the high price and safety critical nature of large forgings for turbomachinery, there is great interest in the application of imaging algorithms to inspection data. However, small flaw indications that cannot be sufficiently resolved have to be characterized using amplitude-based quantification. One such method is the distance gain size method, which converts the maximum echo amplitudes into the diameters of penny-shaped equivalent size reflectors. The approach presented in this contribution combines the synthetic aperture focusing technique (SAFT) with an iterative inversion scheme to locate and quantify small flaws in a more reliable way. Ultrasonic inspection data obtained in a pulse-echo configuration are reconstructed by means of an Synthetic Focusing Technique (SAFT). From the reconstructed data, the amount and approximate location of small flaws are extracted. These predetermined positions, along with the constrained defect model of a penny-shaped crack, provide the initial parametrization for an elastodynamic simulation based on the Kirchhoff approximation. The identification of the optimal parameter set is achieved through an iteratively regularized Gauss-Newton method. By testing the characterization method on a series of flat-bottom holes under laboratory conditions, we demonstrate that the procedure is applicable over a wide range of defect sizes. To show suitability for large forging inspection, we additionally evaluate the inspection data of a large generator shaft forging of 0.6-m diameter. PMID:27116736

  13. Formation of P3KHT:PCBM bulk-heterojunction using orthogonal solvents by ultrasonic spray method

    Science.gov (United States)

    Mahajan, Mrunal S.; Lonkar, Ganesh S.; Ghosh, Sanjay S.; Patil, Mahendra B.; Dalal, Dipak S.; Sali, Jaydeep V.

    2015-07-01

    Bulk-heterojunction (BHJ) morphologies with pure domains and sharp interfaces can lead to a more pronounced photovoltaic performance in organic solar cells. In this paper we report the formation of bulk-heterojunction of P3KHT (poly [3-(sodium-6 hexanoate) thiophene-2, 5-diyl]) and PCBM (phenyl-C61-butyric acid methyl ester) using orthogonal solvents by the ultrasonic spray method, which can lead to pure phases and sharp interfaces. P3KHT and PCBM are soluble in water and chlorobenzene respectively, which are orthogonal solvents. The modelling and simulation of the ultrasonic spray method is reported, and shows the possibility of formation of interconnecting phases of the two components in P3KHT:PCBM BHJ, formed using orthogonal solvents, if specific process parameters are chosen. The modelling and simulation also presents a way to determine optimum parameter space in an intermittent spray deposition method using orthogonal solvents. P3KHT:PCBM BHJ has been prepared using three different approaches. Significant photoluminescence quenching, suggesting efficient excitons separation before recombination has been observed in BHJ prepared by the ‘emulsion of solutions’ method. The study of the optical properties of P3KHT:PCBM BHJ suggests that the BHJ may contain bilayer type structures embedded in the BHJ morphology, which is further confirmed by complementary experiments. This new approach to preparing BHJ with pure phase domains and sharp donor/acceptor interfaces may find applications in optoelectronic devices such as organic thin-film transistors, photodetectors, organic light emitting diodes and organic solar cells.

  14. Formation of P3KHT:PCBM bulk-heterojunction using orthogonal solvents by ultrasonic spray method

    International Nuclear Information System (INIS)

    Bulk-heterojunction (BHJ) morphologies with pure domains and sharp interfaces can lead to a more pronounced photovoltaic performance in organic solar cells. In this paper we report the formation of bulk-heterojunction of P3KHT (poly [3-(sodium-6 hexanoate) thiophene-2, 5-diyl]) and PCBM (phenyl-C61-butyric acid methyl ester) using orthogonal solvents by the ultrasonic spray method, which can lead to pure phases and sharp interfaces. P3KHT and PCBM are soluble in water and chlorobenzene respectively, which are orthogonal solvents. The modelling and simulation of the ultrasonic spray method is reported, and shows the possibility of formation of interconnecting phases of the two components in P3KHT:PCBM BHJ, formed using orthogonal solvents, if specific process parameters are chosen. The modelling and simulation also presents a way to determine optimum parameter space in an intermittent spray deposition method using orthogonal solvents. P3KHT:PCBM BHJ has been prepared using three different approaches. Significant photoluminescence quenching, suggesting efficient excitons separation before recombination has been observed in BHJ prepared by the ‘emulsion of solutions’ method. The study of the optical properties of P3KHT:PCBM BHJ suggests that the BHJ may contain bilayer type structures embedded in the BHJ morphology, which is further confirmed by complementary experiments. This new approach to preparing BHJ with pure phase domains and sharp donor/acceptor interfaces may find applications in optoelectronic devices such as organic thin-film transistors, photodetectors, organic light emitting diodes and organic solar cells. (paper)

  15. Advanced mathematical methods in science and engineering

    CERN Document Server

    Hayek, SI

    2010-01-01

    Ordinary Differential EquationsDEFINITIONS LINEAR DIFFERENTIAL EQUATIONS OF FIRST ORDER LINEAR INDEPENDENCE AND THE WRONSKIAN LINEAR HOMOGENEOUS DIFFERENTIAL EQUATION OF ORDER N WITH CONSTANT COEFFICIENTS EULER'S EQUATION PARTICULAR SOLUTIONS BY METHOD OF UNDETERMINED COEFFICIENTS PARTICULAR SOLUTIONS BY THE METHOD OF VARIATIONS OF PARAMETERS ABEL'S FORMULA FOR THE WRONSKIAN INITIAL VALUE PROBLEMSSeries Solutions of Ordinary Differential EquationsINTRODUCTION POWER SERIES SOLUTIONS CLASSIFICATION

  16. Advances in iterative methods for nonlinear equations

    CERN Document Server

    Busquier, Sonia

    2016-01-01

    This book focuses on the approximation of nonlinear equations using iterative methods. Nine contributions are presented on the construction and analysis of these methods, the coverage encompassing convergence, efficiency, robustness, dynamics, and applications. Many problems are stated in the form of nonlinear equations, using mathematical modeling. In particular, a wide range of problems in Applied Mathematics and in Engineering can be solved by finding the solutions to these equations. The book reveals the importance of studying convergence aspects in iterative methods and shows that selection of the most efficient and robust iterative method for a given problem is crucial to guaranteeing a good approximation. A number of sample criteria for selecting the optimal method are presented, including those regarding the order of convergence, the computational cost, and the stability, including the dynamics. This book will appeal to researchers whose field of interest is related to nonlinear problems and equations...

  17. Experimental investigation of surface quality in ultrasonic machining of WC-Co composites through Taguchi method

    Directory of Open Access Journals (Sweden)

    B. S. Pabla

    2016-08-01

    Full Text Available In manufacturing industries, the demand of WC-Co composite is flourishing because of the distinctive characteristics it offers such as: toughness (with hardness, good dimensional stability, higher mechanical strength etc. However, the difficulties in its machining restrict the application and competitiveness of this material. The current article has been targeted at evaluation of the effect of process conditions (varying power rating, cobalt content, tool material, part thickness, tool geometry, and size of abrasive particle on surface roughness in ultrasonic drilling of WC-Co composite. Results showed that abrasive grit size is most influential factor. From the microstructure analysis, the mode of material deformation has been observed and the parameters, i.e. work material properties, grit size, and power rating was revealed as the most crucial for the deformation mode.

  18. Microstructure and mechanical properties of aluminum–fly ash nano composites made by ultrasonic method

    International Nuclear Information System (INIS)

    Highlights: ► Nano structured fly ash has been produced by 30 h milling time. ► Al–fly ash nano composites were produced by ultrasonic cavitation route. ► A homogeneous distribution of nano fly ash particles was observed in the matrix. ► No additional contamination in the nano composites from the atmosphere. ► Presence of nano fly ash leads to improvement in the strength of the composites. -- Abstract: In this paper an attempt has been made to modify the micro sized fly ash into nano structured fly ash using high energy ball mill. Ball milling was carried out for the total duration of 30 h. The sample was taken out after every 5 h of milling for characterizing. The nano structured fly ash was characterized for its crystallite size and lattice strain by using X-ray diffractometer. It was found that a steady decrease in the crystallite size and increased lattice strain was observed with milling time; the crystallite size at 30 h milling time was found to be 23 nm. The fresh fly ash particles are mostly spherical in shape; whereas the shape of the 30 h milled fly ash particles is irregular and the surface morphology is rough. Al–fly ash nano composites were produced by ultrasonic cavitation route successfully. Scanning electron microscopy images of nano composites reveal a homogeneous distribution of the nano fly ash particles in the AA 2024 matrix. Energy dispersive spectroscopy analysis of nano composites reveals that the fabricated nano composite did not contain any additional contamination from the atmosphere. As the amount of nano fly ash is increasing the hardness of the composite also increasing. The nano fly ash addition leads to improvement in the compression strength of the composites.

  19. Advanced finite element method in structural engineering

    CERN Document Server

    Long, Yu-Qiu; Long, Zhi-Fei

    2009-01-01

    This book systematically introduces the research work on the Finite Element Method completed over the past 25 years. Original theoretical achievements and their applications in the fields of structural engineering and computational mechanics are discussed.

  20. Advanced spectral methods for climatic time series

    Science.gov (United States)

    Ghil, M.; Allen, M.R.; Dettinger, M.D.; Ide, K.; Kondrashov, D.; Mann, M.E.; Robertson, A.W.; Saunders, A.; Tian, Y.; Varadi, F.; Yiou, P.

    2002-01-01

    The analysis of univariate or multivariate time series provides crucial information to describe, understand, and predict climatic variability. The discovery and implementation of a number of novel methods for extracting useful information from time series has recently revitalized this classical field of study. Considerable progress has also been made in interpreting the information so obtained in terms of dynamical systems theory. In this review we describe the connections between time series analysis and nonlinear dynamics, discuss signal- to-noise enhancement, and present some of the novel methods for spectral analysis. The various steps, as well as the advantages and disadvantages of these methods, are illustrated by their application to an important climatic time series, the Southern Oscillation Index. This index captures major features of interannual climate variability and is used extensively in its prediction. Regional and global sea surface temperature data sets are used to illustrate multivariate spectral methods. Open questions and further prospects conclude the review.

  1. Method of Improving Measurement Precision of Ultrasonic Flowmeter%提高超声波流量计量精度的方法

    Institute of Scientific and Technical Information of China (English)

    王璐; 段晨旭; 高泉春; 葛祖郁; 徐丽平; 段培永

    2014-01-01

    时差法超声波流量计通过检测换能器发射和接收的超声波信号的传播时间信号,实现流量的计量。超声波换能器的谐振频率及超声波信号传播过程中相位和幅值的变化等因素,会影响对超声波信号到达时间的准确计量,从而影响流量测量的精度。准确计量超声波信号的到达时刻是提升时差法超生波流量计的计量精度的关键之一。针对换能器发射和接收超声波信号的处理和获取电路进行了设计和分析,得出了实验结果和实验数据,对实验结果给出了实验分析和结论,并通过软件算法给出了进一步提高测量精度的方法。%The ultrasonic flowmeter with transit-time difference method can realize the flow measurement by detecting the propagation time of ultrasonic signals between the transmit and receive from the transducer. The resonant frequency of ultrasonic transducer and the phase and amplitude changes in the process of ultrasonic signal propagation will affect the measurement precision of the arrival time of ultrasonic signal, and the measurement accuracy of ultrasonic flowmeter is affected finally. The precise measurement for arrival time of ultrasonic is one of the effective way to improve the measurement accuracy of ultrasonic flowmeter. The processing and acquisition circuit of the ultrasonic signal transmitted and received are designed and researched by the paper. The experimental results and experimental data are obtained and the experimental analysis and conclusionare given. The way to improve the measurement accuracy is given by software algorithm.

  2. Extension of the crosstalk cancellation method in ultrasonic transducer arrays from the harmonic regime to the transient one.

    Science.gov (United States)

    Bybi, A; Grondel, S; Assaad, J; Hladky-Hennion, A-C

    2014-02-01

    This paper describes a procedure to extend the crosstalk correction method presented in a previous paper [A. Bybi, S. Grondel, J. Assaad, A.-C. Hladky-Hennion, M. Rguiti, Reducing crosstalk in array structures by controlling the excitation voltage of individual elements: a feasibility study, Ultrasonics, 53 (6) (2013) 1135-1140] from the harmonic regime to the transient one. For this purpose a part of an ultrasonic transducer array radiating in water is modeled around the frequency 0.5 MHz using the finite element method. The study is carried out at low frequency in order to respect the same operating conditions than the previous paper. This choice facilitated the fabrication of the transducer arrays and the comparison of the numerical results with the experimental ones. The modeled array is composed of seventeen elements with the central element excited, while the others are grounded. The matching layers and the backing are not taken into account which limits the crosstalk only to the piezoelectric elements and fluid. This consideration reduces the structure density mesh and results in faster computation time (about 25 min for each configuration using a computer with a processor Intel Core i5-3210M, frequency 2.5 GHz and having 4 Go memory (RAM)). The novelty of this research work is to prove the efficiency of the crosstalk correction method in large frequency band as it is the case in medical imaging. The numerical results show the validity of the approach and demonstrate that crosstalk can be reduced by at least 13 dB in terms of displacement. Consequently, the directivity pattern of the individual element can be improved. PMID:24064509

  3. Method of adjusting depth compensation in an ultrasonic-pulse reflection apparatus with respect to uniform fault sensitivity independent of depth

    International Nuclear Information System (INIS)

    With this method, on adjusting depth compensation, there is accounted not only for the decrease of echo hight with distance, caused by the divergence of the ultrasonic beam, but simultaneously for the influence of sound absorption in the workpiece. After adjustment it can also be applied to longitudinal waves. The reflectors are smaller than the beam cross-section. Moreover, there is provided for a three-dimensional scale configuration on the screen of a cathode ray oscillograph being part of the ultrasonic pulse reflection equipment. By means of the scale configuration also the teeth resulting from weak echos are made visible. (RW)

  4. Transonic wing analysis using advanced computational methods

    Science.gov (United States)

    Henne, P. A.; Hicks, R. M.

    1978-01-01

    This paper discusses the application of three-dimensional computational transonic flow methods to several different types of transport wing designs. The purpose of these applications is to evaluate the basic accuracy and limitations associated with such numerical methods. The use of such computational methods for practical engineering problems can only be justified after favorable evaluations are completed. The paper summarizes a study of both the small-disturbance and the full potential technique for computing three-dimensional transonic flows. Computed three-dimensional results are compared to both experimental measurements and theoretical results. Comparisons are made not only of pressure distributions but also of lift and drag forces. Transonic drag rise characteristics are compared. Three-dimensional pressure distributions and aerodynamic forces, computed from the full potential solution, compare reasonably well with experimental results for a wide range of configurations and flow conditions.

  5. Recent advances in coupled-cluster methods

    CERN Document Server

    Bartlett, Rodney J

    1997-01-01

    Today, coupled-cluster (CC) theory has emerged as the most accurate, widely applicable approach for the correlation problem in molecules. Furthermore, the correct scaling of the energy and wavefunction with size (i.e. extensivity) recommends it for studies of polymers and crystals as well as molecules. CC methods have also paid dividends for nuclei, and for certain strongly correlated systems of interest in field theory.In order for CC methods to have achieved this distinction, it has been necessary to formulate new, theoretical approaches for the treatment of a variety of essential quantities

  6. Contact method or automated immersion technique: possible application and limitations of ultrasonic testing in the fusion reactor

    International Nuclear Information System (INIS)

    The tritium breeding blanket is the most important component of a thermonuclear reactor combining the protective function against plasma impact and heat exchange. The breeding blanket concept is based on the use of helium as coolant and beryllium pebbles as neutron multiplier. As structural material the low-activation ferritic-martensitic steel EUROFER (9Cr-W-V-T) is used. For quality assurance the components of the breeding blankets are tested using different non-destructive testing methods. The contact methodology applies the testing equipment VEO in combination of the 10 MHz array-wheel sensor of the ultrasonic phased array series. Immersion testing is performed using the automated facility KC 200 from GE Inspection technologies.

  7. Procedure for the creation of reproducible acoustic coupling using the ultrasonic contact method for nondestructive testing of materials

    International Nuclear Information System (INIS)

    The transducer is pressed to the specimen, a lubricating coating being applied as an intermediate layer. By means of a vibrator belonging to the transducer there are generated vibrations, the growth rate of the amplitude of the reflected signal picked up being observed. This growth rate is monotonously decreasing. If the growth rate is abruptly decreasing or if the amplitude of the measured signal remains constant the vibrator is turned off, because now good acoustic contact is established. After a short time of waiting for the residual stress of the transducer to decay, recording of the ultrasonic parameters may then be taken up. The method can be applied to thickness measurements and inhomogeneous materials with low surface quality. (RW)

  8. Ultrasonic transducer

    International Nuclear Information System (INIS)

    A description is given of an ultrasonic transducer capable of operating at high temperature and comprising a transducer crystal and a coupling piece. This coupling piece is composed of several thin plates, generally triangular in shape, in a material withstanding corrosion and high temperatures, these plates being applied one against the other by pressure. One of the edges of the coupling piece is designed so as to direct towards the junction surfaces of the various plates the ultrasonic waves reflected from the junction between the coupling piece and the piece to which the ultrasonic waves must be transmitted

  9. Advanced Aqueous Phase Catalyst Development using Combinatorial Methods Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The use of combinatorial methods is proposed to rapidly screen catalyst formulations for the advanced development of aqueous phase oxidation catalysts with greater...

  10. Advanced Bayesian Methods for Lunar Surface Navigation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The key innovation of this project is the application of advanced Bayesian methods to integrate real-time dense stereo vision and high-speed optical flow with an...

  11. Advanced Bayesian Methods for Lunar Surface Navigation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The key innovation of this project will be the application of advanced Bayesian methods to integrate real-time dense stereo vision and high-speed optical flow with...

  12. Advanced Topology Optimization Methods for Conceptual Architectural Design

    DEFF Research Database (Denmark)

    Aage, Niels; Amir, Oded; Clausen, Anders;

    2015-01-01

    This paper presents a series of new, advanced topology optimization methods, developed specifically for conceptual architectural design of structures. The proposed computational procedures are implemented as components in the framework of a Grasshopper plugin, providing novel capacities in...

  13. Ultrasonic-microwave method in preparation of polypyrrole-coated magnetic particles for vitamin D extraction in milk.

    Science.gov (United States)

    Jiao, Zhe; Zhang, Yan; Fan, Hongbo

    2016-07-29

    In this study, a nanocomposite of polypyrrole-coated magnetite nanoparticles (Fe3O4@PPy) was prepared by ultrasonic-microwave technique, and employed as magnetic solid-phase extraction (MSPE) sorbent for extraction of vitamin D from milk samples. The term of the synthesis by ultrasonic-microwave technique was dramatically shortened within 4h compared to 20h by conventional stirring-heating method. The resultant composites incorporating the π-π bonding (between PPy coating and the analytes) and magnetic separation can be applied for vitamin D analysis in complicated samples. Without saponification or protein precipitation, vitamin D2 and vitamin D3 could be captured directly from milk samples by Fe3O4@PPy, and separated by magnetic field with only 0.5mL desorption solvent. The total preparation time was completed within 15min. A method for the determination of vitamin D in milk samples by the Fe3O4@PPy extraction coupled with high performance liquid chromatography (HPLC) was developed. The LODs of vitamin D2 and vitamin D3, based on signal-to-noise ratio (S/N) of 3, were 0.02ng/mL and 0.05ng/mL respectively. The recoveries of vitamin D2 and vitamin D3 from milk samples were in the range of 71.9-90.3%, with relative standard deviations ranging between 3.6%-9.9%. The results indicated that the Fe3O4@PPy can be favorably used for the extraction of the vitamin D in milk samples. PMID:27371018

  14. Advanced methods of treatment of hypophysis adenoma

    Directory of Open Access Journals (Sweden)

    Kan Ya.A.

    2011-03-01

    Full Text Available Hypophysis adenomas are mostly spread in the chiasmatic cellular area. They account 18% of all new brain formations, the structure of pituitary adenomas includes prolactinomas in a large number of cases which are manifested by the syndrome of hyperprolactinemia and hormone inactive hypophysis tumours (35%. Somatotropins (13-15% are lower in frequency, the main clinical feature is acromegalia. One can rarely reveal corticotropins (8-10%, gonadotro-pins (7-9% and thyrotropins (1% and their mixed forms. Transsphenoidal surgical interventions are considered to be methods of choice treatment of hypophysis adenomas and other formations in the chiasmatic cellular area. Alternative methods of treatment are conservative. They can be as an addition to microsurgery (radiotherapy

  15. 小直径钢管超声波水浸法探伤分析%Discussion on Ultrasonic Water Immersion Method for Small Diameter Steel Pipe

    Institute of Scientific and Technical Information of China (English)

    徐轲; 卫栋; 杨力能; 田新新; 易晓明

    2012-01-01

    In this article, it summarized ultrasonic water immersion method from 5 aspects, covering the principle of ultrasonic water immersion method, selecting probe, selecting detection parameter, adjusting detection sensitivity and quality evaluation. Thereamong it introduced selecting detection parameters in detail, such as eccentricity, water layer thickness, focus and etc. At the same time, it analyzed the difference between ultrasonic water immersion method and contact detection method, introduced its advantages, disadvantages and range of use of ultrasonic water immersion, and pointed out problems needing attention during detection process.%主要从超声波水浸法探伤的原理、探头的选择、探测参数的选择、探伤灵敏度的调整和质量评定5方面综述了小直径钢管的超声波水浸探伤方法,其中详细介绍了探测参数,如偏心距、水层厚度、焦距等的选择.分析了超声波水浸法探伤与接触法探伤的区别,介绍了超声波水浸法的优缺点和使用范围,指出了水浸法探伤过程中应注意的问题.

  16. Scaling up the Single Transducer Thickness-Independent Ultrasonic Imaging Method for Accurate Characterization of Microstructural Gradients in Monolithic and Composite Tubular Structures

    Science.gov (United States)

    Roth, Don J.; Carney, Dorothy V.; Baaklini, George Y.; Bodis, James R.; Rauser, Richard W.

    1998-01-01

    Ultrasonic velocity/time-of-flight imaging that uses back surface reflections to gauge volumetric material quality is highly suited for quantitative characterization of microstructural gradients including those due to pore fraction, density, fiber fraction, and chemical composition variations. However, a weakness of conventional pulse-echo ultrasonic velocity/time-of-flight imaging is that the image shows the effects of thickness as well as microstructural variations unless the part is uniformly thick. This limits this imaging method's usefulness in practical applications. Prior studies have described a pulse-echo time-of-flight-based ultrasonic imaging method that requires using a single transducer in combination with a reflector plate placed behind samples that eliminates the effect of thickness variation in the image. In those studies, this method was successful at isolating ultrasonic variations due to material microstructure in plate-like samples of silicon nitride, metal matrix composite, and polymer matrix composite. In this study, the method is engineered for inspection of more complex-shaped structures-those having (hollow) tubular/curved geometry. The experimental inspection technique and results are described as applied to (1) monolithic mullite ceramic and polymer matrix composite 'proof-of-concept' tubular structures that contain machined patches of various depths and (2) as-manufactured monolithic silicon nitride ceramic and silicon carbide/silicon carbide composite tubular structures that might be used in 'real world' applications.

  17. An advanced method of heterogeneous reactor theory

    International Nuclear Information System (INIS)

    Recent approaches to heterogeneous reactor theory for numerical applications were presented in the course of 8 lectures given in JAERI. The limitations of initial theory known after the First Conference on Peacefull Uses of Atomic Energy held in Geneva in 1955 as Galanine-Feinberg heterogeneous theory:-matrix from of equations, -lack of consistent theory for heterogeneous parameters for reactor cell, -were overcome by a transformation of heterogeneous reactor equations to a difference form and by a development of a consistent theory for the characteristics of a reactor cell based on detailed space-energy calculations. General few group (G-number of groups) heterogeneous reactor equations in dipole approximation are formulated with the extension of two-dimensional problem to three-dimensions by finite Furie expansion of axial dependence of neutron fluxes. A transformation of initial matrix reactor equations to a difference form is presented. The methods for calculation of heterogeneous reactor cell characteristics giving the relation between vector-flux and vector-current on a cell boundary are based on a set of detailed space-energy neutron flux distribution calculations with zero current across cell boundary and G calculations with linearly independent currents across the cell boundary. The equations for reaction rate matrices are formulated. Specific methods were developed for description of neutron migration in axial and radial directions. The methods for resonance level's approach for numerous high-energy resonances. On the basis of these approaches the theory, methods and computer codes were developed for 3D space-time react or problems including simulation of slow processes with fuel burn-up, control rod movements, Xe poisoning and fast transients depending on prompt and delayed neutrons. As a result reactors with several thousands of channels having non-uniform axial structure can be feasibly treated. (author)

  18. Advanced diagnostic methods for human brucellosis

    OpenAIRE

    Taleski, Vaso; Kunguloski, Dzoko

    2011-01-01

    Brucellosis is a typical zoonotic disease caused by organisms of genus brucella. Humans become infected by ingestion of animal food products, direct contact with infected animals or inhalation of infectious aerosols. Variable symptoms, sub-clinical and atypical infections make diagnosis of human brucellosis difficult. Objective of this paper is to evaluate specificity and sensitivity of different diagnostic methods, on large number of samples, in patients at different stages of...

  19. Advanced Topology Optimization Methods for Conceptual Architectural Design

    DEFF Research Database (Denmark)

    Aage, Niels; Amir, Oded; Clausen, Anders;

    2014-01-01

    This paper presents a series of new, advanced topology optimization methods, developed specifically for conceptual architectural design of structures. The proposed computational procedures are implemented as components in the framework of a Grasshopper plugin, providing novel capacities in topolo......This paper presents a series of new, advanced topology optimization methods, developed specifically for conceptual architectural design of structures. The proposed computational procedures are implemented as components in the framework of a Grasshopper plugin, providing novel capacities...

  20. Development and improvement of synthetic imaging methods for non-destructive ultrasonic testing of complex industrial components

    International Nuclear Information System (INIS)

    The goal of this thesis was, initially, to evaluate phased array methods for ultrasonic Non Destructive Testing (NDT) in order to propose optimizations, or to develop new alternative methods. In particular, this works deals with the detection of defects in complex geometries and/or materials parts. The TFM (Total Focusing Method) algorithm provides high resolution images and several representations of a same defect thanks to different reconstruction modes. These properties have been exploited judiciously in order to propose an adaptive imaging method in immersion configuration. We showed that TFM imaging can be used to characterize more precisely the defects. However, this method presents two major drawbacks: the large amount of data to be processed and a low signal-to-noise ratio (SNR), especially in noisy materials. We developed solutions to these two problems. To overcome the limitation caused by the large number of signals to be processed, we propose an algorithm that defines the sparse array to activate. As for the low SNR, it can be now improved by use of virtual sources and a new filtering method based on the DORT method (Decomposition of the Time Reversal Operator). (author)

  1. Advances in organometallic synthesis with mechanochemical methods.

    Science.gov (United States)

    Rightmire, Nicholas R; Hanusa, Timothy P

    2016-02-14

    Solvent-based syntheses have long been normative in all areas of chemistry, although mechanochemical methods (specifically grinding and milling) have been used to good effect for decades in organic, and to a lesser but growing extent, inorganic coordination chemistry. Organometallic synthesis, in contrast, represents a relatively underdeveloped area for mechanochemical research, and the potential benefits are considerable. From access to new classes of unsolvated complexes, to control over stoichiometries that have not been observed in solution routes, mechanochemical (or 'M-chem') approaches have much to offer the synthetic chemist. It has already become clear that removing the solvent from an organometallic reaction can change reaction pathways considerably, so that prediction of the outcome is not always straightforward. This Perspective reviews recent developments in the field, and describes equipment that can be used in organometallic synthesis. Synthetic chemists are encouraged to add mechanochemical methods to their repertoire in the search for new and highly reactive metal complexes and novel types of organometallic transformations. PMID:26763151

  2. Advancements in Research Synthesis Methods: From a Methodologically Inclusive Perspective

    Science.gov (United States)

    Suri, Harsh; Clarke, David

    2009-01-01

    The dominant literature on research synthesis methods has positivist and neo-positivist origins. In recent years, the landscape of research synthesis methods has changed rapidly to become inclusive. This article highlights methodologically inclusive advancements in research synthesis methods. Attention is drawn to insights from interpretive,…

  3. Advanced Methods and Applications in Computational Intelligence

    CERN Document Server

    Nikodem, Jan; Jacak, Witold; Chaczko, Zenon; ACASE 2012

    2014-01-01

    This book offers an excellent presentation of intelligent engineering and informatics foundations for researchers in this field as well as many examples with industrial application. It contains extended versions of selected papers presented at the inaugural ACASE 2012 Conference dedicated to the Applications of Systems Engineering. This conference was held from the 6th to the 8th of February 2012, at the University of Technology, Sydney, Australia, organized by the University of Technology, Sydney (Australia), Wroclaw University of Technology (Poland) and the University of Applied Sciences in Hagenberg (Austria). The  book is organized into three main parts. Part I contains papers devoted to the heuristic approaches that are applicable in situations where the problem cannot be solved by exact methods, due to various characteristics or  dimensionality problems. Part II covers essential issues of the network management, presents intelligent models of the next generation of networks and distributed systems ...

  4. Current methods and advances in bone densitometry

    Energy Technology Data Exchange (ETDEWEB)

    Guglielmi, G. [Dept. of Radiology, Scientific Inst. ``CSS``, San Giovanni Rotondo (Italy); Glueer, C.C. [Dept. of Radiology, Musculoskeletal Section and Osteoporosis Research Group, Univ. of California, San Francisco, CA (United States); Majumdar, S. [Dept. of Radiology, Musculoskeletal Section and Osteoporosis Research Group, Univ. of California, San Francisco, CA (United States); Blunt, B.A. [Dept. of Radiology, Musculoskeletal Section and Osteoporosis Research Group, Univ. of California, San Francisco, CA (United States); Genant, H.K. [Dept. of Radiology, Musculoskeletal Section and Osteoporosis Research Group, Univ. of California, San Francisco, CA (United States)

    1995-08-01

    Bone mass is the primary, although not the only, determinant of fracture. Over the past few years a number of noninvasive techniques have been developed to more sensitively quantitate bone mass. These include single and dual photon absorptiometry (SPA and DPA), single and dual X-ray absorptiometry (SXA and DXA) and quantitative computed tomography (QCT). While differing in anatomic sites measured and in their estimates of precision, accuracy, and fracture discrimination, all of these methods provide clinically useful measurements of skeletal status. It is the intent of this review to discuss the pros and cons of these techniques and to present the new applications of ultrasound (US) and magnetic resonance (MRI) in the detection and management of osteoporosis. (orig.)

  5. Current methods and advances in bone densitometry

    Science.gov (United States)

    Guglielmi, G.; Gluer, C. C.; Majumdar, S.; Blunt, B. A.; Genant, H. K.

    1995-01-01

    Bone mass is the primary, although not the only, determinant of fracture. Over the past few years a number of noninvasive techniques have been developed to more sensitively quantitate bone mass. These include single and dual photon absorptiometry (SPA and DPA), single and dual X-ray absorptiometry (SXA and DXA) and quantitative computed tomography (QCT). While differing in anatomic sites measured and in their estimates of precision, accuracy, and fracture discrimination, all of these methods provide clinically useful measurements of skeletal status. It is the intent of this review to discuss the pros and cons of these techniques and to present the new applications of ultrasound (US) and magnetic resonance (MRI) in the detection and management of osteoporosis.

  6. Ultrasonic Direction Measurement Method Using Sensitivity Compensated Transmitting Signal and Pulse Compression

    Science.gov (United States)

    Chimura, Dai; Toh, Ryo; Motooka, Seiichi

    We have studied high resolution pulse compression technique for ultrasonic pulse-echo measurement. To acquire broader and flatter spectrum, a Sensitivity Compensate Transmitting (SCT) signal was proposed. The SCT signal is calculated from inversed filtering of received signal. Here, two types SCT signal are proposed. As a Sensitivity Compensated AM (SCAM) signal, an amplitude modulated chirp wave is proposed. Furthermore, for higher Signal to Noise Ratio (SNR), a non-linear FM signal is proposed as a Sensitivity Compensate FM (SCFM) signal. In this paper, effectiveness of the SCT signal on 2-D direction measurement is discussed. By using the SCT signal, the time resolution of compressed pulse is improved, and accuracies of direction measurement using the SCT signal are improved than that of using the chirp wave. Furthermore, by using the SCFM signal, accuracy of direction measurement is improved than that of using the SCAM signal when the target is located at the position where the SNR of received signal is lower.

  7. Micro-molding with ultrasonic vibration energy: new method to disperse nanoclays in polymer matrices.

    Science.gov (United States)

    Planellas, Marc; Sacristán, Matías; Rey, Lorena; Olmo, Cristian; Aymamí, Joan; Casas, María T; del Valle, Luis J; Franco, Lourdes; Puiggalí, Jordi

    2014-07-01

    Ultrasound technology was proved as an efficient processing technique to obtain micro-molded specimens of polylactide (PLA) and polybutylene succinate (PBS), which were selected as examples of biodegradable polyesters widely employed in commodity and specialty applications. Operational parameters such as amplitude, molding force and processing time were successfully optimized to prepare samples with a decrease in the number average molecular weight lower than 6%. Ultrasonic waves also seemed an ideal energy source to provide effective disaggregation of clay silicate layers, and therefore exfoliated nanocomposites. X-ray diffraction patterns of nanocomposites prepared by direct micro-molding of PLA or PBS powder mixtures with natural montmorillonite or different organo-modified clays showed the disappearance of the 001 silicate reflection for specimens having up to 6 wt.% clay content. All electron micrographs revealed relatively homogeneous dispersion and sheet nanostructures oriented in the direction of the melt flow. Incorporation of clay particles during processing had practically no influence on PLA characteristics but enhanced PBS degradation when an organo-modifier was employed. This was in agreement with thermal stability data deduced from thermogravimetric analysis. Cold crystallization experiments directly performed on micro-molded PLA specimens pointed to a complex influence of clay particles reflected by the increase or decrease of the overall non-isothermal crystallization rate when compared to the neat polymer. In all cases, the addition of clay led to a clear decrease in the Avrami exponent. PMID:24457002

  8. Low frequency ultrasonic multi-mode Lamb wave method for characterizing the ultra-thin transversely isotropic laminate composite: Theory and experiment

    Institute of Scientific and Technical Information of China (English)

    ZHANG Rui; WAN Mingxi; CHEN Xiao; CAO Wenwu

    2001-01-01

    A low-frequency multi-mode ultrasonic Lamb wave method suitable for characterizing the thickness, the density and the elastic constants of the ultra-thin transversely isotropic laminate composite is presented, The "ultra-thin" here means that the thickness of the plate is much less than the wavelength of the ultrasonic wave so that the echoes from the front and back faces of the plate can't be separated in the time domain. The dispersion equations for the low frequency ultrasonic Lamb waves with the propagation directions parallel and vertical to the fiber direction are derived. In conjunction with the least square algorithm method, the secant algorithm is used to estimate the parameters of the ultra-thin fiber-reinforced composite layer. The evaluation errors and the sensitivity of the method to different parameters of the thin composite are analyzed. The technique has been used to characterize the ultra-thin grass fiber reinforced PES composite with thickness down to ten percents of the ultrasonic wavelength. It is observed that the agreement between the nominal and the estimation values is reasonably good.

  9. A Verification Method of Wide Range in Ultrasonic Flowmeter%一种超声流量计检定方法

    Institute of Scientific and Technical Information of China (English)

    李浩; 王让定; 姚灵

    2012-01-01

    In order to ensure the performance of ultrasonic flowmeter measurement stability, ultrasonic flowmeter must be strictly taken a verification before being put into produetization. A verification method which is reliable is proposed in this paper. This method which is based on national verification regulation adjusts the flow point of verification according analyzing the accuracy influence of ultrasonic flowmeter caused by the fluid state. According to the experiment, the method can reflect the real quality of ultrasonic flowmeter truly and reliably, and can be operated and spreaded easily.%为了保证超声流量计计量性能的稳定性,超声流量计在产品化前必须先进行严格的检定,本文提出一种可靠的检定方法.该方法在国家检定规程的基础上,分析了流体状态对超声流量计精度影响,调整和增加超声流量计检定规程规定的检定流量点.实验表明,该检定方法能真实可靠反映被检定流量计的真实情况,且操作实际可行,可推广性强.

  10. Advanced intelligent systems

    CERN Document Server

    Ryoo, Young; Jang, Moon-soo; Bae, Young-Chul

    2014-01-01

    Intelligent systems have been initiated with the attempt to imitate the human brain. People wish to let machines perform intelligent works. Many techniques of intelligent systems are based on artificial intelligence. According to changing and novel requirements, the advanced intelligent systems cover a wide spectrum: big data processing, intelligent control, advanced robotics, artificial intelligence and machine learning. This book focuses on coordinating intelligent systems with highly integrated and foundationally functional components. The book consists of 19 contributions that features social network-based recommender systems, application of fuzzy enforcement, energy visualization, ultrasonic muscular thickness measurement, regional analysis and predictive modeling, analysis of 3D polygon data, blood pressure estimation system, fuzzy human model, fuzzy ultrasonic imaging method, ultrasonic mobile smart technology, pseudo-normal image synthesis, subspace classifier, mobile object tracking, standing-up moti...

  11. Ultrasonic stir welding process and apparatus

    Science.gov (United States)

    Ding, R. Jeffrey (Inventor)

    2009-01-01

    An ultrasonic stir welding device provides a method and apparatus for elevating the temperature of a work piece utilizing at least one ultrasonic heater. Instead of relying on a rotating shoulder to provide heat to a workpiece an ultrasonic heater is utilized to provide ultrasonic energy to the workpiece. A rotating pin driven by a motor assembly performs the weld on the workpiece. A handheld version can be constructed as well as a fixedly mounted embodiment.

  12. Study of an ultrasonic method of estimating local temperatures of liquid sodium at the output of the core of SFRs

    International Nuclear Information System (INIS)

    In the frame of research on Sodium cooled Fast nuclear Reactor (SFR), CEA aims to develop an innovative instrumentation, specific to these reactors. The present work relates to the measurement of the sodium temperature at the outlet of the assemblies of the reactor's core by an ultrasonic method. This instrumentation involves the propagation of ultrasonic waves in liquid sodium, thermally inhomogeneous and turbulent. Environment causes deviations of the acoustic beam that must be understood to predict and quantify to consider ultrasound as a measure means in a core of SFR reactor. To determine the magnitude of these influences, a code named AcRaLiS (Acoustic Ray in Liquid Sodium) has been implemented. In a first step, a thermal-hydraulic study specific to the medium, was conducted to provide an adequate description of the environment and choose a suitable acoustic propagation model. Then an implementation has been performed to allow rapid simulations of the wave propagation at several megahertz in this particular environment. This code provides ultrasounds deviations and changes in beam intensity.Two experiments were designed and conducted to verify the code. The first, named UPSilon innovates by replacing sodium by silicone oil in order to have a stable thermal inhomogeneity during the experiment. It allows to determine the validity of the code AcRaLiS with thermal inhomogeneities. The second, called IKHAR allows to study the influence of water turbulence on the propagation of waves, using the Kelvin-Helmholtz instabilities. Conclusions and perspectives are presented, including perspectives for other application domains. (author)

  13. Method and ethics in advancing jury research.

    Science.gov (United States)

    Robertshaw, P

    1998-10-01

    In this article the contemporary problems of the jury and jury research are considered. This is timely, in view of the current Home Office Consultation Paper on the future of, and alternatives to, the jury in serious fraud trials, to which the author has submitted representations on its jury aspects. The research position is dominated by the prohibitions in the Contempt of Court Act 1981. The types of indirect research on jury deliberation which have been achieved within this stricture are outlined. In the USA, direct research of the jury is possible but, for historical reasons, it has been in television documentaries that direct observation of the deliberation process has been achieved. The first issue is discussed and the problems of inauthenticity, 'the observer effect', and of existential invalidity in 'mock' or 'shadow' juries are noted. Finally, the kinds of issues that could be addressed if licensed jury deliberation research was legalized, are proposed. It is also suggested that there are methods available to transcend the problems associated with American direct research. PMID:9808945

  14. Ultrasonic speech translator and communications system

    Science.gov (United States)

    Akerman, M. Alfred; Ayers, Curtis W.; Haynes, Howard D.

    1996-01-01

    A wireless communication system undetectable by radio frequency methods for converting audio signals, including human voice, to electronic signals in the ultrasonic frequency range, transmitting the ultrasonic signal by way of acoustical pressure waves across a carrier medium, including gases, liquids, or solids, and reconverting the ultrasonic acoustical pressure waves back to the original audio signal. The ultrasonic speech translator and communication system (20) includes an ultrasonic transmitting device (100) and an ultrasonic receiving device (200). The ultrasonic transmitting device (100) accepts as input (115) an audio signal such as human voice input from a microphone (114) or tape deck. The ultrasonic transmitting device (100) frequency modulates an ultrasonic carrier signal with the audio signal producing a frequency modulated ultrasonic carrier signal, which is transmitted via acoustical pressure waves across a carrier medium such as gases, liquids or solids. The ultrasonic receiving device (200) converts the frequency modulated ultrasonic acoustical pressure waves to a frequency modulated electronic signal, demodulates the audio signal from the ultrasonic carrier signal, and conditions the demodulated audio signal to reproduce the original audio signal at its output (250).

  15. Comparison of X-Ray, Millimeter Wave, Shearography and Through-Transmission Ultrasonic Methods for Inspection of Honeycomb Composites

    Science.gov (United States)

    Abou-Khousa, M. A.; Ryley, A.; Kharkovsky, S.; Zoughi, R.; Daniels, D.; Kreitinger, N.; Steffes, G.

    2007-03-01

    Honeycomb composites are increasingly finding utility in a variety of environments and applications, such as aircraft structural components, flight control components, radomes, etc. In-service and environmental stresses can produce unwanted flaws that adversely affect the structural integrity and functionality of these composites. These flaws may be in the forms of disbonds, delaminations, impact damage, crushed honeycomb, moisture intrusion, internal cracks, etc. There are several nondestructive testing (NDT) methods that may be used to inspect these composites for the presence and evaluation of these flaws. Such NDT methods include X-ray computed tomography, near-field millimeter wave, shearography, and ultrasonic testing. To assess the capabilities of these methods for honeycomb composite inspection, two honeycomb composites panels were produced with several embedded flaws and missing material primarily representing planar disbonds at various levels within the thickness of the panels and with different shapes. Subsequently, the aforementioned NDT methods were used to produce images of the two panels. This paper presents the results of these investigations and a comparison among the capabilities of these methods.

  16. A dealiasing method for use with ultrasonic pulsed Doppler in measuring velocity profiles and flow rates in pipes

    International Nuclear Information System (INIS)

    The ultrasonic pulsed Doppler method (UDM) is a powerful tool for measuring velocity profiles in a pipe. However, the maximum detectable velocity is limited by the Nyquist sampling theorem. Furthermore, the maximum detectable velocity (also called Nyquist velocity), vmax, and the maximum measurable length are related and cannot be increased at the same time. If the velocity is greater than vmax, velocity aliasing occurs. Hence, the higher velocity that occurs with a larger pipe diameter, i.e. under higher flow rate conditions, cannot be measured with the conventional UDM. To overcome these limitations, dual-pulse repetition frequency (dual PRF) and feedback methods were employed in this study to measure velocity profiles in a pipe. The velocity distributions obtained with the feedback method were found to be more accurate than those obtained with the dual PRF method. However, misdetection of the Nyquist folding number using the feedback method was found to increase with the flow velocity. A feedback method with a moving average is proposed to improve the measurement accuracy. The method can accurately measure the velocity distributions at a velocity five times greater than the maximum velocity that can be measured with the conventional UDM. The measurement volume was found to be among the important parameters that must be considered in assessing the traceability of the reflector during the pulse emission interval. Hence, a larger measurement volume is required to measure higher velocities using the dual PRF method. Integrating velocity distributions measured using the feedback method with a moving average makes it possible to accurately determine flow rates six times greater than those that can be determined using the conventional pulsed Doppler method. (paper)

  17. Advanced methods of solid oxide fuel cell modeling

    CERN Document Server

    Milewski, Jaroslaw; Santarelli, Massimo; Leone, Pierluigi

    2011-01-01

    Fuel cells are widely regarded as the future of the power and transportation industries. Intensive research in this area now requires new methods of fuel cell operation modeling and cell design. Typical mathematical models are based on the physical process description of fuel cells and require a detailed knowledge of the microscopic properties that govern both chemical and electrochemical reactions. ""Advanced Methods of Solid Oxide Fuel Cell Modeling"" proposes the alternative methodology of generalized artificial neural networks (ANN) solid oxide fuel cell (SOFC) modeling. ""Advanced Methods

  18. Strategy to Promote Active Learning of an Advanced Research Method

    Science.gov (United States)

    McDermott, Hilary J.; Dovey, Terence M.

    2013-01-01

    Research methods courses aim to equip students with the knowledge and skills required for research yet seldom include practical aspects of assessment. This reflective practitioner report describes and evaluates an innovative approach to teaching and assessing advanced qualitative research methods to final-year psychology undergraduate students. An…

  19. 超声波-酶法提取牛跟腱胶原蛋白%Extraction of Collagen from Bovine Tendon by Ultrasonic - Enzymatic Method

    Institute of Scientific and Technical Information of China (English)

    张云凤

    2015-01-01

    分别采用胃蛋白酶法与超声波-酶法提取牛跟腱胶原蛋白,比较了两种方法胶原蛋白的产率,并对胶原蛋白进行光谱测试.实验证明,超声波酶法的产率明显较高.%This study compared the collagen yield which extracted from bovine tendon by stomach protein enzymatic method and ultrasonic-enzymatic method. The collagen was tested by infrared spectrum and ultraviolet spectrum. Experiments showed that the yield of ultrasonic-enzymatic method was significantly higher than stomach protein enzymatic method.

  20. Development on ultrasonic testing technique for weldment of small diameter pipe branch. A case of trouble at a nuclear power station and development of ultrasonic testing technique (V-detection method)

    International Nuclear Information System (INIS)

    The weldment between a mother tube and a nozzle stub of small diameter pipings at a nuclear power station (austenitic stainless steel) has conventionally been inspected by the liquid penetrant testing (PT). However, on December, 1998, a leak trouble caused by inner flaw at welded portion formed, and then to confirm soundness of the weldment, necessity of not surface inspection (containing PT, and so on) but volume inspection was required. For the volume inspection, there were considered on radiographic testing (RT) and ultrasonic testing (UT). However, RT has a limitation such as detection of radiation in site and so on, so application of UT has been desired. To solve a problem with conventional method, a flaw detection arrangement to input ultrasonic wave directly to a flaw was considered. Because of V-letter arrangement of a detection feeler for transmission and receiving to a branch pipe, this method is called V-detection method. As a result of an experiment on nozzle stub weldment at an actual machine by using this method, it was found that all of flaws in the nozzle stub detected by RT could also be detected by using UT. (G.K.)

  1. Time difference based measurement of ultrasonic cavitations in wastewater treatment

    Institute of Scientific and Technical Information of China (English)

    朱昌平

    2016-01-01

    Intensity of cavitation is significant in ultrasonic wastewater treatment, but is complicated to measure.A time difference based method of ultrasonic cavitation measurement is proposed.The time differences at different powers of 495kHz ultrasonic are measured in experiment in comparison with conductimetric method.Simulation results show that time difference and electrical conductivity are both approximately positive proportional to the ultrasonic power.The degradation of PNP solution verifies the availability in wastewater treatment by using ultrasonic.

  2. Application of ultrasonic phased array technique for inspection of stud bolts in nuclear reactor vessel

    International Nuclear Information System (INIS)

    The stud bolt is one of crucial parts for safety of reactor vessels in nuclear power plants. Cracks initiation and propagation were reported in stud bolts using closure of reactor vessel and head. Stud bolts are inspected by ultrasonic technique during overhaul periodically for the prevention of stud bolt failure and radioactive leakage from nuclear reactor. In conventional ultrasonic testing for inspection of stud bolts, crack was detected by using shadow effect. It take too much time to inspect stud bolt by using conventional ultrasonic technique. In addition, there were numerous spurious signal reflected from every thread. In this study, the advanced ultrasonic phased array technique was introduced for inspect stud bolts. The phased array technique provide fast inspection and high detectability of defects. There are sector scanning and linear scanning method in phased array technique, and these scanning methods were applied to inspect stud bolt and detectability was investigated.

  3. Ultrasonic magnetic abrasive finishing

    Institute of Scientific and Technical Information of China (English)

    LU Ya-ping; MA Ji; ZHANG Jun-qiang; WANG Long-shan

    2006-01-01

    Put forward a new kind of polishing method, ultrasonic magnetic abrasive finishing (UMAF), and studied its mechanism of improving polishing efficiency. By analyzing all kind of forces acting on single abrasive particle in the polishing process and calculating the size of the composition of forces, get the conclusion that UMAF will enhance the efficiency of the normal magnetic abrasive finishing(MAF) due to the ultrasonic vibration increases the cutting force and depth. At last the idea of designing the UMAF system based on numerical control milling machine is put forward which is convenient to setup and will accelerate the practical application of MAF.

  4. Technical Letter Report Assessment of Ultrasonic Phased Array Inspection Method for Welds in Cast Austenitic Stainless Steel Pressurizer Surge Line Piping JCN N6398, Task 1B

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, Aaron A.; Cinson, Anthony D.; Crawford, Susan L.; Mathews, Royce; Moran, Traci L.; Anderson, Michael T.

    2009-07-28

    Research is being conducted for the U.S. Nuclear Regulatory Commission (NRC) at the Pacific Northwest National Laboratory (PNNL) to assess the effectiveness and reliability of advanced nondestructive examination (NDE) methods for the inspection of light water reactor components. The scope of this research encompasses primary system pressure boundary materials including cast austenitic stainless steels (CASS); dissimilar metal welds; piping with corrosion-resistant cladding; weld overlays, inlays and onlays; and far-side examinations of austenitic piping welds. A primary objective of this work is to evaluate various NDE methods to assess their ability to detect, localize, and size cracks in coarse-grained steel components. In this effort, PNNL supports cooperation with Commissariat à l’Energie Atomique (CEA) to assess reliable inspection of CASS materials. The NRC Project Manager has established a cooperative effort with the Institut de Radioprotection et de Surete Nucleaire (IRSN). CEA, under funding from IRSN, are supporting collaborative efforts with the NRC and PNNL. Regarding its work on the NDE of materials, CEA is providing its modeling software (CIVA) in exchange for PNNL offering expertise and data related to phased-array detection and sizing, acoustic attenuation, and back scattering on CASS materials. This collaboration benefits the NRC because CEA performs research and development on CASS for Électricité de France (EdF). This technical letter report provides a summary of a technical evaluation aimed at assessing the capabilities of phased-array (PA) ultrasonic testing (UT) methods as applied to the inspection of welds in CASS pressurizer (PZR) surge line nuclear reactor piping. A set of thermal fatigue cracks (TFCs) was implanted into three CASS PZR surge-line specimens (pipe-to-elbow welds) that were fabricated using vintage CASS materials formed in the 1970s, and flaw responses from these cracks were used to evaluate detection and sizing

  5. Ultrasonic neuromodulation

    Science.gov (United States)

    Naor, Omer; Krupa, Steve; Shoham, Shy

    2016-06-01

    Ultrasonic waves can be non-invasively steered and focused into mm-scale regions across the human body and brain, and their application in generating controlled artificial modulation of neuronal activity could therefore potentially have profound implications for neural science and engineering. Ultrasonic neuro-modulation phenomena were experimentally observed and studied for nearly a century, with recent discoveries on direct neural excitation and suppression sparking a new wave of investigations in models ranging from rodents to humans. In this paper we review the physics, engineering and scientific aspects of ultrasonic fields, their control in both space and time, and their effect on neuronal activity, including a survey of both the field’s foundational history and of recent findings. We describe key constraints encountered in this field, as well as key engineering systems developed to surmount them. In closing, the state of the art is discussed, with an emphasis on emerging research and clinical directions.

  6. Flaw acceptance criteria taking into consideration the NDT: radiographic and ultrasonic testing. Analysis through the fracture mechanics methods

    International Nuclear Information System (INIS)

    The present study compares and evaluates the flaw acceptance criteria of the non-destructive inspections meeting European Community standards, through the application of the fracture mechanics methods that were determined and verified by the previous activity. Some choices were made; these, however, do not change the general validity of the conclusions. Shaved full-penetration butt welds of Class 1 components making up the primary circuit were considered and the following parameters varied: standards: French, German, Italian (ASME III) and UK; material: AISI 316 and low alloy steel A 533; base material and weld metal; temperature: RT, 370 deg C for the austenitic and 260 deg C for the ferritic steel; ultrasonic and radiographic methods; defect position: surface and internal; stress condition: situations with different primary and secondary stresses. From a preliminary examination of this study it is evident that the large quantity of results available and the abundance of information contained therein make a simple and exhaustive synthesis difficult. In fact, different analyses are possible and we have, therefore, limited the research to activities to perform a comparison and a general evaluation of the acceptance criteria of the non-destructive testing. (authors). 57 refs., 25 figs., 11 tabs

  7. Some properties of horn equation model of ultrasonic system vibration and of transfer matrix and equivalent circuit methods of its solution.

    Science.gov (United States)

    Hornišová, K; Billik, P

    2014-01-01

    Traditional technique of horn equation solved by transfer matrices as a model of vibration of ultrasonic systems consisting of sectional transducer, horn and load is discussed. Expression of vibration modes as a ratio of solutions of two Schrödinger equations gives better insight to the structure of a transfer matrix and properties of amplitudes of displacement and strain, and enables more systematic search for analytic solutions. Incorrectness of impedance matrix method and of equivalent circuit method on one hand and correctness and advantages of transfer matrix method in avoiding numerical artifacts and revealing the real features of the model on the other hand are demonstrated on examples. Discontinuous dependence of the nth resonant value on parameters of ultrasonic system, recently described in Sturm-Liouville theory, and consequently, a jump from half-wave to full-wave mode, is observed in a transducer model.

  8. Irradiation Testing of Ultrasonic Transducers

    International Nuclear Information System (INIS)

    Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of numerous parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of single, small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other efforts include an ultrasonic technique to detect morphology changes (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of existing knowledge of ultrasonic transducer material survivability under irradiation conditions. To address this need, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate promising magnetostrictive and piezoelectric transducer performance in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2 (E> 0.1 MeV). This test will be an instrumented lead test; and real-time transducer performance data will be collected along with temperature and neutron and gamma flux data. By characterizing magnetostrictive and piezoelectric transducer survivability during irradiation, test results will enable the development of novel radiation tolerant ultrasonic sensors for use in Material and Test Reactors (MTRs). The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers. (authors)

  9. Irradiation Testing of Ultrasonic Transducers

    Energy Technology Data Exchange (ETDEWEB)

    Daw, Joshua; Tittmann, Bernhard; Reinhardt, Brian; Kohse, Gordon E.; Ramuhalli, Pradeep; Montgomery, Robert O.; Chien, Hual-Te; Villard, Jean-Francois; Palmer, Joe; Rempe, Joy

    2014-07-30

    Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of single, small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other efforts include an ultrasonic technique to detect morphology changes (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of existing knowledge of ultrasonic transducer material survivability under irradiation conditions. For this reason, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate promising magnetostrictive and piezoelectric transducer performance in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2 (E> 0.1 MeV). The goal of this research is to characterize magnetostrictive and piezoelectric transducer survivability during irradiation, enabling the development of novel radiation tolerant ultrasonic sensors for use in Material and Test Reactors (MTRs). As such, this test will be an instrumented lead test and real-time transducer performance data will be collected along with temperature and neutron and gamma flux data. The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers.

  10. METHODS ADVANCEMENT FOR MILK ANALYSIS: THE MAMA STUDY

    Science.gov (United States)

    The Methods Advancement for Milk Analysis (MAMA) study was designed by US EPA and CDC investigators to provide data to support the technological and study design needs of the proposed National Children=s Study (NCS). The NCS is a multi-Agency-sponsored study, authorized under the...

  11. Method and Tools for Development of Advanced Instructional Systems

    NARCIS (Netherlands)

    Arend, J. van der; Riemersma, J.B.J.

    1994-01-01

    The application of advanced instructional systems (AISs), like computer-based training systems, intelligent tutoring systems and training simulators, is widely spread within the Royal Netherlands Army. As a consequence there is a growing interest in methods and tools to develop effective and efficie

  12. Structural and Morphological Properties of Nanostructured ZnO Particles Grown by Ultrasonic Spray Pyrolysis Method with Horizontal Furnace

    Directory of Open Access Journals (Sweden)

    G. Flores-Carrasco

    2014-01-01

    Full Text Available ZnO nanoparticles were synthesized in a horizontal furnace at 500°C using different zinc nitrate hexahydrate concentrations (0.01 and 0.1 M as reactive solution by ultrasonic spray pyrolysis method. The physical-chemical properties of synthesized ZnO nanoparticles have been characterized by thermogravimetric analysis (TGA, X-ray diffraction (XRD, scanning electron microscopy (SEM, energy dispersive spectroscopy (EDS, and high resolution transmission electron microscopy (HRTEM. With the TGA is has optimized the temperature at which the initial reactive (Zn(NO32·6H2O, is decomposed completely to give way to its corresponding oxide, ZnO. SEM revealed secondary particles with a quasispherical shape that do not change significantly with the increasing of precursor solution concentration as well as some content of the broken spheres. Increasing the precursor solution concentration leads to the increase in the average size of ZnO secondary particles from 248±73 to 470±160 nm; XRD reveals the similar tendency for the crystallite size which changes from 23±4 to 45±4 nm. HRTEM implies that the secondary particles are with hierarchical structure composed of primary nanosized subunits. These results showed that the precursor concentration plays an important role in the evolution on the size, stoichiometry, and morphology of ZnO nanoparticles.

  13. A Model for Measured Traveling Waves at End-Diastole in Human Heart Wall by Ultrasonic Imaging Method

    Science.gov (United States)

    Bekki, Naoaki; Shintani, Seine A.; Ishiwata, Shin'ichi; Kanai, Hiroshi

    2016-04-01

    We observe traveling waves, measured by the ultrasonic noninvasive imaging method, in a longitudinal beam direction from the apex to the base side on the interventricular septum (IVS) during the period from the end-diastole to the beginning of systole for a healthy human heart wall. We present a possible phenomenological model to explain part of one-dimensional cardiac behaviors for the observed traveling waves around the time of R-wave of echocardiography (ECG) in the human heart. Although the observed two-dimensional patterns of traveling waves are extremely complex and no one knows yet the exact solutions for the traveling homoclinic plane wave in the one-dimensional complex Ginzburg-Landau equation (CGLE), we numerically find that part of the one-dimensional homoclinic dynamics of the phase and amplitude patterns in the observed traveling waves is similar to that of the numerical homoclinic plane-wave solutions in the CGLE with periodic boundary condition in a certain parameter space. It is suggested that part of the cardiac dynamics of the traveling waves on the IVS can be qualitatively described by the CGLE model as a paradigm for understanding biophysical nonlinear phenomena.

  14. Optimization of Ultrasonic-Assisted Extraction of Flavonoid Compounds and Antioxidants from Alfalfa Using Response Surface Method

    Directory of Open Access Journals (Sweden)

    Chang-Liang Jing

    2015-08-01

    Full Text Available Ultrasonic-assisted extraction (UAE was used to extract flavonoid-enriched antioxidants from alfalfa aerial part. Response surface methodology (RSM, based on a four-factor, five-level central composite design (CCD, was employed to obtain the optimal extraction parameters, in which the flavonoid content was maximum and the antioxidant activity of the extracts was strongest. Radical scavenging capacity of the extracts, which represents the amounts of antioxidants in alfalfa, was determined by using 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonicacid (ABTS and 2,2′-diphenyl-1-picrylhydrazyl (DPPH methods. The results showed good fit with the proposed models for the total flavonoid extraction (R2 = 0.9849, for the antioxidant extraction assayed by ABTS method (R2 = 0.9764, and by DPPH method (R2 = 0.9806. Optimized extraction conditions for total flavonoids was a ratio of liquid to solid of 57.16 mL/g, 62.33 °C, 57.08 min, and 52.14% ethanol. The optimal extraction parameters of extracts for the highest antioxidant activity by DPPH method was a ratio of liquid to solid 60.3 mL/g, 54.56 °C, 45.59 min, and 46.67% ethanol, and by ABTS assay was a ratio of liquid to solid 47.29 mL/g, 63.73 °C, 51.62 min, and 60% ethanol concentration. Our work offers optimal extraction conditions for total flavonoids and antioxidants from alfalfa.

  15. Ultrasonic transducer

    International Nuclear Information System (INIS)

    An ultrasonic transducer suitable for use up to a temperature of about 6000C comprises a stainless steel casing containing a lithium niobate piezoelectric element and a backing material of a powder which provides a partial pressure of oxygen and thereby prevents deterioration of the element by oxygen loss or contamination. The powder might be of lithium niobate or magnesia. (author)

  16. Advanced Measuring (Instrumentation Methods for Nuclear Installations: A Review

    Directory of Open Access Journals (Sweden)

    Wang Qiu-kuan

    2012-01-01

    Full Text Available The nuclear technology has been widely used in the world. The research of measurement in nuclear installations involves many aspects, such as nuclear reactors, nuclear fuel cycle, safety and security, nuclear accident, after action, analysis, and environmental applications. In last decades, many advanced measuring devices and techniques have been widely applied in nuclear installations. This paper mainly introduces the development of the measuring (instrumentation methods for nuclear installations and the applications of these instruments and methods.

  17. Research on model testing of a new ultrasonic multi-wave detecting method

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ The traditional crack exploring method with echo (reflected wave) in metals is called the "single-wave detecting method" that uses a probe of single weight. This method is not able to detect directly the size and shape of the crack and the result can only be obtained by relative comparison, that is to compare the echo amplitudes of the unknown quantity (crack) with the known quantity (regular artificial crack) to determine the equivalent size and shape of a certain crack. In this way, the site of a crack can be basically determined, but it is not the size, scale and site of the actual crack. So the traditional method is incapable to satisfy the demands in real applications, and there was not any big improvement in the past several decades. Therefore, we introduce a new method called the "multi-wave detecting method" in the paper, which is capable to detect directly the size, scale and site of a crack.

  18. Higher geometry an introduction to advanced methods in analytic geometry

    CERN Document Server

    Woods, Frederick S

    2005-01-01

    For students of mathematics with a sound background in analytic geometry and some knowledge of determinants, this volume has long been among the best available expositions of advanced work on projective and algebraic geometry. Developed from Professor Woods' lectures at the Massachusetts Institute of Technology, it bridges the gap between intermediate studies in the field and highly specialized works.With exceptional thoroughness, it presents the most important general concepts and methods of advanced algebraic geometry (as distinguished from differential geometry). It offers a thorough study

  19. Effect of Particle Addition on Degradation Rate of Methylene Blue in an Ultrasonic Field

    Science.gov (United States)

    Honma, Chiemi; Kobayashi, Daisuke; Matsumoto, Hideyuki; Takahashi, Tomoki; Kuroda, Chiaki; Otake, Katsuto; Shono, Atsushi

    2013-07-01

    Ultrasound has been found to be an attractive advanced technology for the degradation of hazardous organic compounds in water. In addition, the sonochemical reaction is enhanced by particle addition. However, the enhancement mechanism of particle addition has not been investigated well, because ultrasound enhances not only chemical reactions but also mass transfer. In this study, the ultrasonic degradation of methylene blue was carried out, and the effects of the ultrasonic irradiation condition on the degradation rate were investigated. The effect of ultrasonic frequency on the improvement of degradation by particle addition was also investigated. The order of degradation rate with frequency was the same as the tendency of sonochemical efficiency value obtained using KI oxidation dosimetry method (SEKI). The degradation process of methylene blue was intensified by particle addition, and the degradation rate increased with increasing amount of particle addition. The enhancement of degradation rate by particle addition was influenced by both ultrasonic frequency and type or diameter of particles.

  20. Acousto-ultrasonic nondestructive evaluation of materials using laser beam generation and detection

    Science.gov (United States)

    Huber, Robert D.; Green, Robert E., Jr.; Vary, Alex; Kautz, Harold

    1990-01-01

    Presented in viewgraph format, the possibility of using laser generation and detection of ultrasound to replace piezoelectric transducers for the acousto-ultrasonic technique is advanced. The advantages and disadvantages of laser acousto-ultrasonics are outlined. Laser acousto-ultrasonics complements standard piezoelectric acousto-ultrasonics and offers non-contact nondestructive evaluation.

  1. Comparative study of nonlinear ultrasonic methods applied to experimental models of prostheses osseointegration

    OpenAIRE

    RIVIERE, Jacques; Haupert, Sylvain; Johnson, Paul; Laugier, Pascal

    2012-01-01

    International audience This study is part of the long-term perspective to implement in vivo some new noninvasive methods to monitor the bone prostheses sealing or osseointegration (dental implants, hip prostheses). Although the most widely used clinically, X-ray radiography suffers from low sensitivity, limiting for instance its ability to detect early loosening of a prosthesis. The potential of methods developed over the past twenty years and based on elasticity measurements has been show...

  2. IMPROVEMENT OF METHODS AND MEANS OF ULTRASONIC CONTROL OF METAL GOODS WITH MODIFIED SURFACE LAYER

    Directory of Open Access Journals (Sweden)

    A. R. Baev

    2011-01-01

    Full Text Available In the report perspective methods of diagnostics of surface layers state of products after various technological processes (a face hardening by means of induction or after cementation, coating are viewed. The testing is carried out to geometrical attributes (thickness of a layer and presence of flaws. The offered methods of measuring allow making the test in a work cycle of products manufacture.

  3. Optimisation of Ultrasonic Conditions as an Advanced Extraction Technique for Recovery of Phenolic Compounds and Antioxidant Activity from Macadamia (Macadamia tetraphylla) Skin Waste

    OpenAIRE

    Adriana Dailey; Quan V. Vuong

    2015-01-01

    Thousands of tons of macadamia skin waste are generated annually with very limited utilisation of this extensive by-product. The aim of this study was to develop optimal ultrasonic extraction conditions for maximized recovery of phenolic compounds and antioxidant properties from macadamia skin using Response Surface Methodology (RSM). Three ultrasonic parameters, including temperature (30–50 °C), time (10–50 min) and power (150–250 W), were tested for their impact on the extraction of total p...

  4. A Study on the Ultrasonic Sensor and Accelerometer Installation and Signal Acquisition Method for Engine Condition Diagnosis on EDG in Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Guk; Choi, Kwang Hee; Choi, You Sung [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2012-05-15

    As a plan for the improvement of the EDG (Emergency Diesel Generator) maintenance program, the research project is being done by changing from time to condition based maintenance. First of all, the condition of EDG was analyzed and CBM(Condition Based Maintenance) was applied. The diagnoses for EDG are mainly composed of combustion in cylinders, vibration and ultrasonic signal analysis. The combustion analysis provides information of the combustion performance on each cylinder of EDG. Vibration and ultrasonic analysis provide timing signal on each event and information on mechanical condition. These signals can be collected without trouble causing on the operation of EDG. In this paper, the optimum sensor installation and the signal acquisition method are described for monitoring and diagnosis of EDG

  5. Properties of ultrasonic testing systems

    International Nuclear Information System (INIS)

    For a long time, ultrasonic testing of reactor components and plants whose safety had to meet high demands, lacked definitions of the required properties of the ultrasonic testing system. The standard draft DIN 25 450 states demands on the ultrasonic testing unit and the test heads and recommends measuring methods to determine their properties. With test units and test heads meeting the demands of the draft a better reproducibility of the test is obtained than before; the improved test statement results in an increased safety during production and operation of components and plants. (orig./HP)

  6. Recent advances in radial basis function collocation methods

    CERN Document Server

    Chen, Wen; Chen, C S

    2014-01-01

    This book surveys the latest advances in radial basis function (RBF) meshless collocation methods which emphasis on recent novel kernel RBFs and new numerical schemes for solving partial differential equations. The RBF collocation methods are inherently free of integration and mesh, and avoid tedious mesh generation involved in standard finite element and boundary element methods. This book focuses primarily on the numerical algorithms, engineering applications, and highlights a large class of novel boundary-type RBF meshless collocation methods. These methods have shown a clear edge over the traditional numerical techniques especially for problems involving infinite domain, moving boundary, thin-walled structures, and inverse problems. Due to the rapid development in RBF meshless collocation methods, there is a need to summarize all these new materials so that they are available to scientists, engineers, and graduate students who are interest to apply these newly developed methods for solving real world’s ...

  7. S55Cr大型模块超声探伤方法探究%Study on Ultrasonic Inspection Method for S55Cr Large Modules

    Institute of Scientific and Technical Information of China (English)

    吴国秋

    2015-01-01

    The ultrasonic inspection for ultra thick and ultra thin material is still a difficult problem. Because of large cross section of ultra thick material, it’s difficult to be forged for the material and deformed for the heart part of the material, so the poor forgeability of the material will form uneven microstructure which will cause the serious scat⁃tering and acoustic attenuation during the ultrasonic inspection. Lack of fine grain composition in S55Cr steel, uneven grain or coarse grain will easily cause the adverse effect of ultrasonic inspection. During the ultrasonic inspection there often exists the UT unqualified phenomenon not meeting the specified requirements of the standard due to insufficient margin bottom echo. The flexible use of various ultrasonic detection methods and equipments solved the problem exist⁃ed during the ultrasonic inspection of S55Cr steel large modules with the lowest cost and the fastest way.%对超声波检测而言,超厚和超薄材料检测一直是难题。由于超厚材料断面超大,锻造难度大,心部变形困难,锻透性差,易发生组织不均匀,造成散射严重、声波衰减大。S55Cr缺乏细化晶粒成分,极易因晶粒不均匀或粗大,给超声波探伤带来不利影响,常常出现因底面回波余量不足造成达不到标准规定的现象导致超探不合格。本文灵活运用多种超声检测方法及设备手段,用最低的成本、最快的办法解决了S55Cr大型模块超声波探伤中出现的这一问题。

  8. Evaluation of an ultrasonic method for measurement of oil film thickness in a hydraulic motor piston ring

    OpenAIRE

    Harper, P; Dwyer-Joyce, R.S.; Sjodin, U.; Olofsson, U.

    2005-01-01

    The efficiency of a hydraulic motor depends on the lubrication performance of the piston ring. If the film is too thin then wear occurs quickly, if it is too thick then oil is lost into the cylinder and efficiency is reduced. In this paper a technique for oil film measurement based on ultrasonic reflection is investigated. This has the potential to be used non-invasively on real components. An ultrasonic pulse will reflect from a thin film interposed between two solids. The proportion of the ...

  9. Advanced symbolic analysis for VLSI systems methods and applications

    CERN Document Server

    Shi, Guoyong; Tlelo Cuautle, Esteban

    2014-01-01

    This book provides comprehensive coverage of the recent advances in symbolic analysis techniques for design automation of nanometer VLSI systems. The presentation is organized in parts of fundamentals, basic implementation methods and applications for VLSI design. Topics emphasized include  statistical timing and crosstalk analysis, statistical and parallel analysis, performance bound analysis and behavioral modeling for analog integrated circuits . Among the recent advances, the Binary Decision Diagram (BDD) based approaches are studied in depth. The BDD-based hierarchical symbolic analysis approaches, have essentially broken the analog circuit size barrier. In particular, this book   • Provides an overview of classical symbolic analysis methods and a comprehensive presentation on the modern  BDD-based symbolic analysis techniques; • Describes detailed implementation strategies for BDD-based algorithms, including the principles of zero-suppression, variable ordering and canonical reduction; • Int...

  10. NATO Advanced Study Institute on Methods in Computational Molecular Physics

    CERN Document Server

    Diercksen, Geerd

    1992-01-01

    This volume records the lectures given at a NATO Advanced Study Institute on Methods in Computational Molecular Physics held in Bad Windsheim, Germany, from 22nd July until 2nd. August, 1991. This NATO Advanced Study Institute sought to bridge the quite considerable gap which exist between the presentation of molecular electronic structure theory found in contemporary monographs such as, for example, McWeeny's Methods 0/ Molecular Quantum Mechanics (Academic Press, London, 1989) or Wilson's Electron correlation in moleeules (Clarendon Press, Oxford, 1984) and the realization of the sophisticated computational algorithms required for their practical application. It sought to underline the relation between the electronic structure problem and the study of nuc1ear motion. Software for performing molecular electronic structure calculations is now being applied in an increasingly wide range of fields in both the academic and the commercial sectors. Numerous applications are reported in areas as diverse as catalysi...

  11. Current advances in diagnostic methods of Acanthamoeba keratitis

    Institute of Scientific and Technical Information of China (English)

    Wang Yuehua; Feng Xianmin; Jiang Linzhe

    2014-01-01

    Objective The objective of this article was to review the current advances in diagnostic methods for Acanthamoeba keratitis (AK).Data sources Data used in this review were retrieved from PubMed (1970-2013).The terms "Acanthamoeba keratitis" and "diagnosis" were used for the literature search.Study selection Data from published articles regarding AK and diagnosis in clinical trials were identified and reviewed.Results The diagnostic methods for the eight species implicated in AK were reviewed.Among all diagnostic procedures,corneal scraping and smear examination was an essential diagnostic method.Polymerase chain reaction was the most sensitive and accurate detection method.Culturing of Acanthamoeba was a reliable method for final diagnosis of AK.Confocal microscopy to detect Acanthamoeba was also effective,without any invasive procedure,and was helpful in the early diagnosis of AK.Conclusion Clinically,conjunction of various diagnostic methods to diagnose AK was necessary.

  12. Characterization and comparison of defects detection limits of three ultrasonic non destructive methods

    OpenAIRE

    Welemane H.; Eyma F.; Pescay C.; Péronnet E.

    2010-01-01

    This work deals with the Liquid Resin Infusion (LRI) process developed within the research program “FUSelage COMPosite” of DAHER SOCATA. This manufacturing process enables the realization of complex composite structures or fuselage elements in a single phase (mono-material), which considerably reduce connections and relative difficulties. The concern here is the investigation of non destructive testing (NDT) methods that can be applied to LRI-structures in order to define their capaciti...

  13. Simultaneous assessment of bone thickness and velocity for ultrasonic computed tomography using transmission-echo method

    OpenAIRE

    Zheng, Rui; Lasaygues, Philippe

    2013-01-01

    The robustness and accuracy of the transmissionecho (TE) method is investigated on simultaneous thickness and velocity estimation of double-layered thin bone samples. Twentytwo pairs of bovine cortical samples were assembled and measured by two pairs of immersion transducers with nominal frequencies of 1MHz and 2.25MHz. For each measurement, the TOF of six pulses contained by one transmission and two echo signals were detected and then used for the calculation. The mean relative errors of eff...

  14. Advanced Regression Methods in Finance and Economics: Three Essays

    OpenAIRE

    Hofmarcher, Paul

    2012-01-01

    In this thesis advanced regression methods are applied to discuss and investigate highly relevant research questions in the areas of finance and economics. In the field of credit risk the thesis investigates a hierarchical model which allows to obtain a consensus score, if several ratings are available for each firm. Autoregressive processes and random effects are used to model both a correlation structure between and within the obligors in the sample. The model also allows to validate ...

  15. Ultrasonic Microtransport

    Science.gov (United States)

    Moroney, Richard Morgan, III

    We have observed numerous kinetic effects using ultrasonic flexural plate waves (FPWs) in 4mu -thick composite plates of low-stress silicon nitride, piezoelectric zinc oxide and aluminum. The wavelength is typically 100 mum, and the area 3 x 8 mm^2. A successful new surface micromachining fabrication process is presented here for the first time. FPWs have been used to move liquids and gasses with motion typically indicated by polysilicon blocks in air and polystyrene spheres in water; the velocity in air is 4.5 mm/s (with a zero-to-peak input of 3 V), and in water it is 100 mum/s (with an input of 7.8 V). Other observations include pumping of a liquid dye, and mixing near the FPW surface. All quantitative observations demonstrate that the kinetic effects of FPWs are proportional to the square of the wave amplitude. The amplitude for a typical device is 250 A at 9 V input; the power in a typical FPW is about 2 mW. The amplitude can be accurately measured using a laser diffraction technique. Experimental error is about +/-10%, and many of the results agree well with a simple theory to predict the FPW amplitude; extensions of the theory model the fluid loading of FPW devices, but experiment and theory disagree by about 15%. Pumping by flexural plate waves is an example of the phenomenon known as acoustic streaming. A common solution approach is the method of successive approximations, where the nonlinear equations are first linearized and solved. This "first-order" solution is then used to determine the inhomogeneous source terms in the linearized, "second -order" equations of motion. Theoretical predictions of streaming theory are in excellent agreement with experiment in the case where the FPW device contacts a half-space of fluid; predictions for flow in small channels encourage the development of integrated micropumps. Applications for microflow include thermal redistribution in integrated circuits and liquid movement in analytical instruments--particularly where

  16. Accurate measurement of ultrasonic velocity by eliminating the diffraction effect

    Institute of Scientific and Technical Information of China (English)

    WEI Tingcun

    2003-01-01

    The accurate measurement method of ultrasonic velocity by the pulse interferencemethod with eliminating the diffraction effect has been investigated in VHF range experimen-tally. Two silicate glasses were taken as the specimens, their frequency dependences of longitu-dinal velocities were measured in the frequency range 50-350 MHz, and the phase advances ofultrasonic signals caused by diffraction effect were calculated using A. O. Williams' theoreticalexpression. For the frequency dependences of longitudinal velocities, the measurement resultswere in good agreement with the simulation ones in which the phase advances were included.It has been shown that the velocity error due to diffraction effect can be corrected very well bythis method.

  17. Ultrasonic Evaluation of Well Integrity

    OpenAIRE

    Hoel, Kristian

    2014-01-01

    This thesis presents the acoustic theory behind current ultrasonic cement evaluation tools. The UltraSonic Imager tool's pulse echo technique and the new Isolation Scanner tool's pitch-catch leaky lamb wave measuring technique is explained. A laboratory experiment is conducted on a steel casing set-up (BeCaLoS) designed by SINTEF Petroleum Research to test, and highlight weaknesses of these measuring techniques. Both evaluation methods are successfully performed under four differen...

  18. Advanced applications of boundary-integral equation methods

    International Nuclear Information System (INIS)

    Numerical analysis has become the basic tool for both design and research problems in solid mechanics. The need for accuracy and detail, plus the availablity of the high speed computer has led to the development of many new modeling methods ranging from general purpose structural analysis finite element programs to special purpose research programs. The boundary-integral equation (BIE) method is based on classical mathematical techniques but is finding new life as a basic stress analysis tool for engineering applications. The paper summarizes some advanced elastic applications of fracture mechanics and three-dimensional stress analysis, while referencing some of the much broader developmental effort. Future emphasis is needed to exploit the BIE method in conjunction with other techniques such as the finite element method through the creation of hybrid stress analysis methods. (Auth.)

  19. Digital spectral analysis parametric, non-parametric and advanced methods

    CERN Document Server

    Castanié, Francis

    2013-01-01

    Digital Spectral Analysis provides a single source that offers complete coverage of the spectral analysis domain. This self-contained work includes details on advanced topics that are usually presented in scattered sources throughout the literature.The theoretical principles necessary for the understanding of spectral analysis are discussed in the first four chapters: fundamentals, digital signal processing, estimation in spectral analysis, and time-series models.An entire chapter is devoted to the non-parametric methods most widely used in industry.High resolution methods a

  20. Advanced thermal hydraulic method using 3x3 pin modeling

    International Nuclear Information System (INIS)

    Advanced thermal hydraulic methods are being developed as part of the US DOE sponsored Nuclear Hub program called CASL (Consortium for Advanced Simulation of LWRs). One of the key objectives of the Hub program is to develop a multi-physics tool which evaluates neutronic, thermal hydraulic, structural mechanics and nuclear fuel rod performance in rod bundles to support power uprates, increased burnup/cycle length and life extension for US nuclear plants. Current design analysis tools are separate and applied in series using simplistic models and conservatisms in the analysis. In order to achieve key Nuclear Hub objectives a higher fidelity, multi-physics tool is needed to address the challenge problems that limit current reactor performance. This paper summarizes the preliminary development of a multi-physics tool by performing 3x3 pin modeling and making comparisons to available data. (author)

  1. 超声刀清洗方法的对比研究%COMPARISON STUDY OF DIFFERENT ULTRASONIC SCALPELS CLEANING METHOD

    Institute of Scientific and Technical Information of China (English)

    陈延茹; 陈静; 倪乐丹; 陈洁; 徐海丽

    2011-01-01

    Objective To observe cleaning effect of used ultrasonic scalpels by three different cleaning methods. Methods Ocular estimation and occult blood test were used to evaluate the cleaning effect of ultrasonic scalpels by 3 different cleaning methods. Results By the methods of ocular estimation and occult blood test, the highest cleaning quality rate was group C, which reaches to 98.68%. The cleaning methodes of multi - enzyme detergent immersion or hydrogen peroxide immersion respectively could not clean thoroughly. Conclusion The used ultrasonic scalpels dipping in multi -enzyme detergent for 5 minutes after prewashing with H2O2 of 30 g/L for 5 min, can reach satisfactory cleaning effect.%目的 观察3种不同的方法对超声刀清洗效果.方法 通过目测法和隐血试验法,对3种清洗方法清洗后超声刀进行了评价.结果 目测法与隐血试验法检测清洗后超声刀洁净质量以c组方法清洗质量合格率最高,均达到98.68%.使用后带血的超声刀单独用多酶洗剂浸泡或过氧化氢浸泡都不足以达到彻底清洗干净.结论 使用后的超声刀经过预清洗,用浓度为30g/L过氧化氢溶液浸泡5 min,再用碱性复合酶稀释液浸泡5 min,进行手工清洗可以获得满意的清洗效果.

  2. 超声波流量测量中流速计算方法的对比%Comparison of flow rate calculation method for ultrasonic flow measurement

    Institute of Scientific and Technical Information of China (English)

    于洋; 宗光华; 丁凤林

    2013-01-01

    超声波流量计(UFM,Ultrasonic Flow Meter)通过测量管路中顺流和逆流方向的超声波传播时间变化计算流速,因此超声波传播时间的准确测量对流量计的精度影响至关重要.对超声波流量计的测量方法进行研究,从环境温度的变化、时间测量的准确性、不确定度的计算3个方面,对比超声波传播时间差法和频率差法对流量测量精度的影响.通过超声波流量测量实验,验证了在流量计未校准的情况下,与频率差法相比,时间差法的测量精度更高,且其校准系数曲线的线性度更好,校准后可在全流量范围内获得更高的测量精度.%Ultrasonic flow meter ( UFM ) calculates the flow rate, by measuring the difference of ultrasound transit time between the upstream direction and downstream direction. For the purpose of accurate flow measurement, transit time difference method and frequency difference method were compared from three aspects; change of environment temperature, accuracy of time measurement, and uncertainty calculation. Ultrasonic flow measurement experiment shows, when the flow meter is not calibrated, compared with frequency difference method, transit time difference method can achieve better accuracy. The calibrated factor for the transit time difference method is more linear, so better accuracy is achieved for full flow range measurement.

  3. NATO Advanced Research Workshop on Vectorization of Advanced Methods for Molecular Electronic Structure

    CERN Document Server

    1984-01-01

    That there have been remarkable advances in the field of molecular electronic structure during the last decade is clear not only to those working in the field but also to anyone else who has used quantum chemical results to guide their own investiga­ tions. The progress in calculating the electronic structures of molecules has occurred through the truly ingenious theoretical and methodological developments that have made computationally tractable the underlying physics of electron distributions around a collection of nuclei. At the same time there has been consider­ able benefit from the great advances in computer technology. The growing sophistication, declining costs and increasing accessibi­ lity of computers have let theorists apply their methods to prob­ lems in virtually all areas of molecular science. Consequently, each year witnesses calculations on larger molecules than in the year before and calculations with greater accuracy and more com­ plete information on molecular properties. We can surel...

  4. Methods and advances in the study of aeroelasticity with uncertainties

    Institute of Scientific and Technical Information of China (English)

    Dai Yuting; Yang Chao

    2014-01-01

    Uncertainties denote the operators which describe data error, numerical error and model error in the mathematical methods. The study of aeroelasticity with uncertainty embedded in the subsystems, such as the uncertainty in the modeling of structures and aerodynamics, has been a hot topic in the last decades. In this paper, advances of the analysis and design in aeroelasticity with uncertainty are summarized in detail. According to the non-probabilistic or probabilistic uncer-tainty, the developments of theories, methods and experiments with application to both robust and probabilistic aeroelasticity analysis are presented, respectively. In addition, the advances in aeroelastic design considering either probabilistic or non-probabilistic uncertainties are introduced along with aeroelastic analysis. This review focuses on the robust aeroelasticity study based on the structured singular value method, namely the l method. It covers the numerical calculation algo-rithm of the structured singular value, uncertainty model construction, robust aeroelastic stability analysis algorithms, uncertainty level verification, and robust flutter boundary prediction in the flight test, etc. The key results and conclusions are explored. Finally, several promising problems on aeroelasticity with uncertainty are proposed for future investigation.

  5. Measurement of elastic modulus and ultrasonic wave velocity by piezoelectric resonator

    Science.gov (United States)

    Erhart, Jiří

    2015-01-01

    A piezoelectric ceramic resonator is used for the ‘electrical’ measurement of elastic properties, i.e. Young’s modulus and ultrasonic wave velocity in metallic materials. Piezoelectric response is precisely calculated for the piezoelectric ceramic ring fixed at the end of a metallic rod. The piezoelectric ring serves as both an actuator as well as a sensor. The experimental setup and method of measurement using higher overtones is explained in detail and practically demonstrated for a set of different metallic materials. Young’s moduli and ultrasonic wave velocities are measured within 3% relative error. The presented method is suitable for an advanced engineering class or physics laboratory training.

  6. Development of advanced nodal diffusion methods for modern computer architectures

    International Nuclear Information System (INIS)

    A family of highly efficient multidimensional multigroup advanced neutron-diffusion nodal methods, ILLICO, were implemented on sequential, vector, and vector-concurrent computers. Three-dimensional realistic benchmark problems can be solved in vectorized mode in less than 0.73 s (33.86 Mflops) on a Cray X-MP/48. Vector-concurrent implementations yield speedups as high as 9.19 on an Alliant FX/8. These results show that the ILLICO method preserves essentially all of its speed advantage over finite-difference methods. A self-consistent higher-order nodal diffusion method was developed and implemented. Nodal methods for global nuclear reactor multigroup diffusion calculations which account explicitly for heterogeneities in the assembly nuclear properties were developed and evaluated. A systematic analysis of the zero-order variable cross section nodal method was conducted. Analyzing the KWU PWR depletion benchmark problem, it is shown that when burnup heterogeneities arise, ordinary nodal methods, which do not explicitly treat the heterogeneities, suffer a significant systematic error that accumulates. A nodal method that treats explicitly the space dependence of diffusion coefficients was developed and implemented. A consistent burnup-correction method for nodal microscopic depletion analysis was developed

  7. Advanced applications of boundary-integral equation methods

    International Nuclear Information System (INIS)

    The BIE (boundary integral equation) method is based on the numerical solution of a set of integral constraint equations which couple boundary tractions (stresses) to boundary displacements. Thus the dimensionality of the problem is reduced by one; only boundary geometry and data are discretized. Stresses at any set of selected interior points are computed following the boundary solution without any further numerical approximations. Thus, the BIE method has inherently greater resolution capability for stress gradients than does the finite element method. Conversely, the BIE method is not efficient for problems involving significant inhomogeneity such as in multi-thin-layered materials, or in elastoplasticity. Some progress in applyiing the BIE method to the latter problem has been made but much more work remains. Further, the BIE method is only optional for problems with significant stress risers, and only when boundary stresses are most important. Interior stress calculations are expensive, per point, and can drive the solution costs up rapidly. The current report summarizes some of the advanced elastic applications of fracture mechanics and three-dimensional stress analysis, while referencing some of the much broader developmental effort. Future emphasis is needed to exploit the BIE method in conjunction with other techniques such as the finite element method through the creation of hybrid stress analysis methods

  8. Intravascular Ultrasonic Imaging

    OpenAIRE

    Tobis, JM; Mahon, D.; Moriuchi, M; Mallery, JA; Lehmann, K; Griffith, J.; Gessert, J; Zalesky, P; McRae, M; Dwyer, ML; Henry, WL

    1990-01-01

    Because conventional imaging methods are inadequate for evaluating human coronary arteries in vivo, an intravascular ultrasonic imaging catheter was developed that allows the arterial wall to be studied in cross-section from within the artery. The catheter incorporates a mechanically rotating 20-MHz transducer, which is designed so that the ringdown occurs within the catheter and imaging is permitted up to the catheter's surface. The device rotates at 1800-rpm within a plastic sleeve and prov...

  9. Ultrasonic ash/pyrite liberation

    Energy Technology Data Exchange (ETDEWEB)

    Yungman, B.A.; Buban, K.S.; Stotts, W.F.

    1990-06-01

    The objective of this project was to develop a coal preparation concept which employed ultrasonics to precondition coal prior to conventional or advanced physical beneficiation processes such that ash and pyrite separation were enhanced with improved combustible recovery. Research activities involved a series of experiments that subjected three different test coals, Illinois No. 6, Pittsburgh No. 8, and Upper Freeport, ground to three different size fractions (28 mesh [times] 0, 200 mesh [times] 0, and 325 mesh [times] 0), to a fixed (20 kHz) frequency ultrasonic signal prior to processing by conventional and microbubble flotation. The samples were also processed by conventional and microbubble flotation without ultrasonic pretreatment to establish baseline conditions. Product ash, sulfur and combustible recovery data were determined for both beneficiation processes.

  10. Lamb Wave Helical Ultrasonic Tomography

    Science.gov (United States)

    Leonard, K. R.; Hinders, M. K.

    2004-02-01

    Ultrasonic guided waves have been used for a wide variety of ultrasonic inspection techniques. We describe here a new variation called helical ultrasound tomography (HUT). This new technique, among other things, has direct application to advanced pipe inspection. HUT uses guided ultrasonic waves along with an adaptation of the tomographic reconstruction algorithms developed by seismologists for what they call "cross borehole" tomography. In HUT, the Lamb-like guided waves travel in various helical crisscross paths between two parallel circumferential transducer arrays instead of the planar crisscross seismic paths between two boreholes. Although the measurement itself is fairly complicated, the output of the tomographic reconstruction is a readily interpretable map of a quantity of interest such as pipe wall thickness. We demonstrate the feasibility of the HUT technique via laboratory scans on steel pipe segments into which controlled thinnings have been introduced.

  11. Finite element analysis simulations for ultrasonic array NDE inspections

    Science.gov (United States)

    Dobson, Jeff; Tweedie, Andrew; Harvey, Gerald; O'Leary, Richard; Mulholland, Anthony; Tant, Katherine; Gachagan, Anthony

    2016-02-01

    Advances in manufacturing techniques and materials have led to an increase in the demand for reliable and robust inspection techniques to maintain safety critical features. The application of modelling methods to develop and evaluate inspections is becoming an essential tool for the NDE community. Current analytical methods are inadequate for simulation of arbitrary components and heterogeneous materials, such as anisotropic welds or composite structures. Finite element analysis software (FEA), such as PZFlex, can provide the ability to simulate the inspection of these arrangements, providing the ability to economically prototype and evaluate improved NDE methods. FEA is often seen as computationally expensive for ultrasound problems however, advances in computing power have made it a more viable tool. This paper aims to illustrate the capability of appropriate FEA to produce accurate simulations of ultrasonic array inspections - minimizing the requirement for expensive test-piece fabrication. Validation is afforded via corroboration of the FE derived and experimentally generated data sets for a test-block comprising 1D and 2D defects. The modelling approach is extended to consider the more troublesome aspects of heterogeneous materials where defect dimensions can be of the same length scale as the grain structure. The model is used to facilitate the implementation of new ultrasonic array inspection methods for such materials. This is exemplified by considering the simulation of ultrasonic NDE in a weld structure in order to assess new approaches to imaging such structures.

  12. Fine analysis on advanced detection of transient electromagnetic method

    Institute of Scientific and Technical Information of China (English)

    Wang Bo; Liu Shengdong; Yang Zhen; Wang Zhijun; Huang Lanying

    2012-01-01

    Fault fracture zones and water-bearing bodies in front of the driving head are the main disasters in mine laneways,thus it is important to perform their advanced detection and prediction in advance in order to provide reliable technical support for the excavation.Based on the electromagnetic induction theory,we analyzed the characteristics of primary and secondary fields with a positive and negative wave form of current,proposed the fine processing of the advanced detection with variation rate of apparent resistivity and introduced in detail the computational formulae and procedures.The result of physical simulation experiments illustrate that the tectonic interface of modules can be judged by first-order rate of apparent resistivity with a boundary error of 5%,and the position of water body determined by the fine analysis method agrees well with the result of borehole drilling.This shows that in terms of distinguishing structure and aqueous anomalies,the first-order rate of apparent resistivity is more sensitive than the secondorder rate of apparent resistivity.However,some remaining problems are suggested for future solutions.

  13. Advances on methods for mapping QTL in plant

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yuan-Ming

    2006-01-01

    Advances on methods for mapping quantitative trait loci (QTL) are firstly summarized.Then, some new methods, including mapping multiple QTL, fine mapping of QTL, and mapping QTL for dynamic traits, are mainly described. Finally, some future prospects are proposed, including how to dig novel genes in the germplasm resource, map expression QTL (eQTL) by the use of all markers,phenotypes and micro-array data, identify QTL using genetic mating designs and detect viability loci. The purpose is to direct plant geneticists to choose a suitable method in the inheritance analysis of quantitative trait and in search of novel genes in germplasm resource so that more potential genetic information can be uncovered.

  14. Advances in product family and product platform design methods & applications

    CERN Document Server

    Jiao, Jianxin; Siddique, Zahed; Hölttä-Otto, Katja

    2014-01-01

    Advances in Product Family and Product Platform Design: Methods & Applications highlights recent advances that have been made to support product family and product platform design and successful applications in industry. This book provides not only motivation for product family and product platform design—the “why” and “when” of platforming—but also methods and tools to support the design and development of families of products based on shared platforms—the “what”, “how”, and “where” of platforming. It begins with an overview of recent product family design research to introduce readers to the breadth of the topic and progresses to more detailed topics and design theory to help designers, engineers, and project managers plan, architect, and implement platform-based product development strategies in their companies. This book also: Presents state-of-the-art methods and tools for product family and product platform design Adopts an integrated, systems view on product family and pro...

  15. Advanced reactor physics methods for heterogeneous reactor cores

    Science.gov (United States)

    Thompson, Steven A.

    To maintain the economic viability of nuclear power the industry has begun to emphasize maximizing the efficiency and output of existing nuclear power plants by using longer fuel cycles, stretch power uprates, shorter outage lengths, mixed-oxide (MOX) fuel and more aggressive operating strategies. In order to accommodate these changes, while still satisfying the peaking factor and power envelope requirements necessary to maintain safe operation, more complexity in commercial core designs have been implemented, such as an increase in the number of sub-batches and an increase in the use of both discrete and integral burnable poisons. A consequence of the increased complexity of core designs, as well as the use of MOX fuel, is an increase in the neutronic heterogeneity of the core. Such heterogeneous cores introduce challenges for the current methods that are used for reactor analysis. New methods must be developed to address these deficiencies while still maintaining the computational efficiency of existing reactor analysis methods. In this thesis, advanced core design methodologies are developed to be able to adequately analyze the highly heterogeneous core designs which are currently in use in commercial power reactors. These methodological improvements are being pursued with the goal of not sacrificing the computational efficiency which core designers require. More specifically, the PSU nodal code NEM is being updated to include an SP3 solution option, an advanced transverse leakage option, and a semi-analytical NEM solution option.

  16. Ultrasonic echo signal fetures of dissimilar material bonding joints

    Institute of Scientific and Technical Information of China (English)

    GANG Tie(刚铁); Yasuo TAKAHASHI

    2004-01-01

    An ultrasonic evaluation method of echo feature of diffusion bond joint between two dissimilar materials is presented. The echo signal was acquired by an automatic ultrasonic C-scan test system. It is found that the intensity of echo and its phase can be used to evaluate the joint quality, and interface products of dissimilar materials bonding can be evaluated by ultrasonic method.

  17. Advanced Methods in Black-Hole Perturbation Theory

    CERN Document Server

    Pani, Paolo

    2013-01-01

    Black-hole perturbation theory is a useful tool to investigate issues in astrophysics, high-energy physics, and fundamental problems in gravity. It is often complementary to fully-fledged nonlinear evolutions and instrumental to interpret some results of numerical simulations. Several modern applications require advanced tools to investigate the linear dynamics of generic small perturbations around stationary black holes. Here, we present an overview of these applications and introduce extensions of the standard semianalytical methods to construct and solve the linearized field equations in curved spacetime. Current state-of-the-art techniques are pedagogically explained and exciting open problems are presented.

  18. Ultrasonic evaluation of end cap weld joints of fuel elements of pressurized heavy water reactors using signal analysis methods

    International Nuclear Information System (INIS)

    This paper describes the application of ultrasonic digital signal analysis for the detection of fine defects of the order of 10% or lower of wall thickness (WT) of 370 microns in the resistance welded end cap-cladding tube joints of fuel elements used in Pressurised Heavy Water Reactors (PHWR s). The results obtained for the detection of such defects, have confirmed the sensitivity and reliability of this approach, and were further validated by destructive metallography. (author)

  19. Optimization of Ultrasonic-Assisted Extraction of Flavonoid Compounds and Antioxidants from Alfalfa Using Response Surface Method

    OpenAIRE

    Chang-Liang Jing; Xiao-Fang Dong; Jian-Ming Tong

    2015-01-01

    Ultrasonic-assisted extraction (UAE) was used to extract flavonoid-enriched antioxidants from alfalfa aerial part. Response surface methodology (RSM), based on a four-factor, five-level central composite design (CCD), was employed to obtain the optimal extraction parameters, in which the flavonoid content was maximum and the antioxidant activity of the extracts was strongest. Radical scavenging capacity of the extracts, which represents the amounts of antioxidants in alfalfa, was determined b...

  20. Detection of plating defects using ultrasonic and eddy current test methods; Nachweis von Plattierungsfehlern mit Ultraschall- und Wirbelstromverfahren

    Energy Technology Data Exchange (ETDEWEB)

    Waidele, H.; Knoch, P. [MPA, Univ. Stuttgart (Germany); Gersinska, R. [BfS Salzgitter (Germany); Brenner, W.; Seidenkranz, T. [TUeV Sued (Germany); Csapo, G.; Just, T. [TUeV Nord (Germany); Weiss, R. [IzfP Saarbruecken (Germany); Rathgeb, W. [IntelligeNDT, Erlangen (Germany)

    2004-07-01

    The validity of ultrasonic and eddy current testing of austenitic platings of reactor pressure vessels was investigated in the context of a project funded by the Federal Radiation Protection Office (Bundesamt fuer Strahlenschutz). In the first phase, test specimens with natural defects were fabricated at MPA Stuttgart; in the second phase, plating defects were introduced in a MPA large-size vessel. Measurements showed that most plating defects will be detected by standard ultrasonic testing. The highest accuracy was achieved by a combination of ultrasonic and eddy current testing. (orig.) [German] Im Rahmen eines vom Bundesamt fuer Strahlenschutz gefoerderten Vorhabens wurde die Aussagefaehigkeit von Ultraschall- und Wirbelstrompruefungen an austenitischen Plattierungen von Reaktordruckbehaeltern untersucht. In der ersten Phase des Vorhabens wurden an der MPA Stuttgart Testkoerper mit natuerlichen Fehlern im Plattierungsbereich gefertigt, in einer zweiten Phase wurden Plattierungsfehler in den MPA-Grossbehaelter eingebracht. Die Messungen haben gezeigt, dass die meisten Plattierungsfehler mit Ultraschall-Standardprueftechniken nachweisbar sind, wobei die groesste Aussagekraft bei einer Kombination von Ultraschall- und Wirbelstrompruefung gegeben ist. (orig.)

  1. Advanced applications of boundary-integral equation methods

    International Nuclear Information System (INIS)

    Numerical analysis has become the basic tool for both design and research problems in solid mechanics. The boundary-integral equation (BIE) method is based on classical mathematical techniques but is finding new life as a basic stress analysis tool for engineering applications. The BIE method is based on the numerical solution of a set of integral constraint equations which couple boundary tractions (stresses) to boundary displacements. Thus the dimensionality of the problem is reduced by one; only boundary geometry and data are discretized. Stresses at any set of selected interior points are computed following the boundary solution without any further numerical approximations. Thus, the BIE method has inherently greater resolution capability for stress gradients than does the finite element method. Conversely, the BIE method is not efficient for problems involving significant inhomogeneity such as in multi-thin-layered materials, or in elastoplasticity. Some progress in applying the BIE method to the latter problem has been made but much more work remains. Further, the BIE method is only optional for problems with significant stress risers, and only when boundary stresses are more important. Interior stress calculations are expensive, per point, and can drive the solution costs up rapidly. The current report summarizes some of the advanced elastic applications of fracture mechanics and three-dimensional stress analysis, while referring some of the much broader developmental effort. (Auth.)

  2. Computer-controlled Sophisticated Ultrasonic Cleaner

    Directory of Open Access Journals (Sweden)

    H. Muthurajan

    2007-01-01

    Full Text Available The significant advantage of ultrasonic cleaning technique is the abilities to clean the delicateand complex shape materials without damaging their surfaces quickly. Ultrasonic cleaners havefound increasing applications in a variety of industries because these offer an environmentallygood alternative to ozone-depleting compounds and hazardous solvents. Also, ultrasonicvibration is one of the methods for chemical synthesis (chemical reaction and of yieldenhancement of chemical engineering process. Consequently, there is a need to developmultipurpose ultrasonic cleaner/vibrator using computer control, which can be used to set thevarious performance parameter of ultrasonic vibrator such as frequency, duty cycle, continuous/pulsed mode, duration of operation, and thermal profile of tank during the process. An ultrasoniccleaner was developed using an oscillator circuit and the duration of oscillator circuit functioningcan be set through the computer. Computerised ultrasonic cleaner using indigenously madepiezoceramic transducers and their advantages over the conventional ultrasonic cleaners are discussed.

  3. Advanced methods for fabrication of PHWR and LMFBR fuels

    International Nuclear Information System (INIS)

    For self-reliance in nuclear power, the Department of Atomic Energy (DAE), India is pursuing two specific reactor systems, namely the pressurised heavy water reactors (PHWR) and the liquid metal cooled fast breeder reactors (LMFBR). The reference fuel for PHWR is zircaloy-4 clad high density (≤ 96 per cent T.D.) natural UO2 pellet-pins. The advanced PHWR fuels are UO2-PuO2 (≤ 2 per cent), ThO2-PuO2 (≤ 4 per cent) and ThO2-U233O2 (≤ 2 per cent). Similarly, low density (≤ 85 per cent T.D.) (UPu)O2 pellets clad in SS 316 or D9 is the reference fuel for the first generation of prototype and commercial LMFBRs all over the world. However, (UPu)C and (UPu)N are considered as advanced fuels for LMFBRs mainly because of their shorter doubling time. The conventional method of fabrication of both high and low density oxide, carbide and nitride fuel pellets starting from UO2, PuO2 and ThO2 powders is 'powder metallurgy (P/M)'. The P/M route has, however, the disadvantage of generation and handling of fine powder particles of the fuel and the associated problem of 'radiotoxic dust hazard'. The present paper summarises the state-of-the-art of advanced methods of fabrication of oxide, carbide and nitride fuels and highlights the author's experience on sol-gel-microsphere-pelletisation (SGMP) route for preparation of these materials. The SGMP process uses sol gel derived, dust-free and free-flowing microspheres of oxides, carbide or nitride for direct pelletisation and sintering. Fuel pellets of both low and high density, excellent microhomogeneity and controlled 'open' or 'closed' porosity could be fabricated via the SGMP route. (author). 5 tables, 14 figs., 15 refs

  4. Advanced Burnup Method using Inductively Coupled Plasma Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Hilton, Bruce A. [Idaho Natonal Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-6188 (United States); Glagolenko, Irina; Giglio, Jeffrey J.; Cummings, Daniel G

    2009-06-15

    Nuclear fuel burnup is a key parameter used to assess irradiated fuel performance, to characterize the dependence of property changes due to irradiation, and to perform nuclear materials accountability. For advanced transmutation fuels and high burnup LWR fuels that have multiple fission sources, the existing Nd-148 ASTM burnup determination practice requires input of calculated fission fractions (identifying the specific fission source isotope and neutron energy that yielded fission, e.g., U-235 from thermal neutron, U-238 from fast neutron) from computational neutronics analysis in addition to the measured concentration of a single fission product isotope. We report a novel methodology of nuclear fuel burnup determination, which is completely independent of model predictions and reactor types. The proposed method leverages the capability of Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to quantify multiple fission products and actinides and uses these data to develop a system of burnup equations whose solution is the fission fractions. The fission fractions are substituted back in the equations to determine burnup. This technique requires high fidelity fission yield data, which is not uniformly available for all fission products. We discuss different means that can potentially assist in indirect determination, verification and improvement (refinement) of the ambiguously known fission yields. A variety of irradiated fuel samples are characterized by ICP-MS and the results used to test the advanced burnup method. The samples include metallic alloy fuel irradiated in fast spectrum reactor (EBRII) and metallic alloy in a tailored spectrum and dispersion fuel in the thermal spectrum of the Advanced Test Reactor (ATR). The derived fission fractions and measured burnups are compared with calculated values predicted by neutronics models. (authors)

  5. Ultrasonic thermometer isolation standoffs

    International Nuclear Information System (INIS)

    A method is provided for minimizing sticking of the transmission line to the protective sheath and preventing noise echoes from interfering with signal echoes in an improved high temperature ultrasonic thermometer which includes an ultrasonic transmission line surrounded by a protective sheath. Small isolation standoffs are mounted on the transmission line to minimize points of contact between the transmission line and the protective sheath, the isolation standoffs serving as discontinuities mounted on the transmission line at locations where a signal echo is desired or where an echo can be tolerated. Consequently any noise echo generated by the sticking of the standoff to the protective sheath only adds to the amplitude of the echo generated at the standoff and does not interfere with the other signal echoes. 6 claims, 3 figures

  6. Methods and Systems for Advanced Spaceport Information Management

    Science.gov (United States)

    Fussell, Ronald M. (Inventor); Ely, Donald W. (Inventor); Meier, Gary M. (Inventor); Halpin, Paul C. (Inventor); Meade, Phillip T. (Inventor); Jacobson, Craig A. (Inventor); Blackwell-Thompson, Charlie (Inventor)

    2007-01-01

    Advanced spaceport information management methods and systems are disclosed. In one embodiment, a method includes coupling a test system to the payload and transmitting one or more test signals that emulate an anticipated condition from the test system to the payload. One or more responsive signals are received from the payload into the test system and are analyzed to determine whether one or more of the responsive signals comprises an anomalous signal. At least one of the steps of transmitting, receiving, analyzing and determining includes transmitting at least one of the test signals and the responsive signals via a communications link from a payload processing facility to a remotely located facility. In one particular embodiment, the communications link is an Internet link from a payload processing facility to a remotely located facility (e.g. a launch facility, university, etc.).

  7. The application of advanced rotor (performance) methods for design calculations

    Energy Technology Data Exchange (ETDEWEB)

    Bussel, G.J.W. van [Delft Univ. of Technology, Inst. for Wind Energy, Delft (Netherlands)

    1997-08-01

    The calculation of loads and performance of wind turbine rotors has been a topic for research over the last century. The principles for the calculation of loads on rotor blades with a given specific geometry, as well as the development of optimal shaped rotor blades have been published in the decades that significant aircraft development took place. Nowadays advanced computer codes are used for specific problems regarding modern aircraft, and application to wind turbine rotors has also been performed occasionally. The engineers designing rotor blades for wind turbines still use methods based upon global principles developed in the beginning of the century. The question what to expect in terms of the type of methods to be applied in a design environment for the near future is addressed here. (EG) 14 refs.

  8. Nondestructive strength evaluation of adhesive-bonded single-lap joints by signal processing method

    International Nuclear Information System (INIS)

    Application of bonding by adhesives can be found in many industries, particularly in advanced technological domains such as the aeronautical and space industries, automobile manufacture, and electronics. Periodic inspection with conventional ultrasonic NDE techniques is capable of indicating the presence and possible location of crack. Continuous ultrasonic attenuation monitoring has potential to supply information. This study used adhesive-bonded single-lap joints specimen to evaluate such possibility by ultrasonic signal processing method

  9. THE CALCULATION OF THE PROFILE-LINEAR AVERAGE VELOCITY IN THE TRANSITION REGION FOR ULTRASONIC HEAT METER BASED ON THE METHOD OF LES*

    Institute of Scientific and Technical Information of China (English)

    LIU Yong-hui; DU Guang-sheng; TAO Li-li; SHEN Fang

    2011-01-01

    The measurement accuracy of an ultrasonic heat meter depends on the relationship of the profile-linear average velocity.There are various methods for the calculation of the laminar and turbulence flow regions, but few methods for the transition region.At present, the traditional method to deal with the transition region is to adopt the relationship for the turbulent flow region. In this article, a simplified model of the pipe is used to study the characteristics of the transition flow with specific Reynolds number. The k-ε model and the Large Eddy Simulation (LES) model are, respectively, used to calculate the flow field of the transition region,and a comparison with the experiment results shows that the LES model is more effective than the k- ε model, it is also shown that there will be a large error if the relationship based on the turbulence flow is used to calculate the profile-linear average velocity relationship of the transition flow. The profile-linear average velocity for the Reynolds number ranging from 5 300 to 10 000 are calculated, and the relationship curve is obtained. The results of this article can be used to improve the measurement accuracy of ultrasonic heat meter and provide a theoretical basis for the research of the whole transition flow.

  10. Estimation of Postmortem Interval by Detecting Thickness of Cornea Using Ultrasonic Method%超声法测量角膜厚度推断死亡时间

    Institute of Scientific and Technical Information of China (English)

    吕国丽; 姜富学; 许心舒; 蒋拥军; 李志刚; 王欣; 石河; 余礼聪; 许传超

    2012-01-01

    目的 用超声法测量角膜厚度,探索其死后变化规律.方法 11只家兔随机分为两组,分别为角膜上皮完整组及去角膜上皮组.后者采用机械刮除法去除角膜上皮.利用超声测厚仪连续监测两组动物的死后多个时间点的角膜厚度,并对角膜厚度变化与死亡时间进行相关回归分析.结果 超声法测量角膜上皮完整组死后兔角膜厚度的变化值与死亡时间呈非线性相关,且具有较强的相关性,相关系数为0.922,而去角膜上皮组的相关系数为0.822.结论 超声法测量角膜厚度对推断早期死亡时间具有较可靠的应用前景.完整的角膜上皮对于超声测量角膜厚度具有关键作用.%Objective To explore the postmortem changes of cornea thickness measured by ultrasonic pachymetry. Methods Eleven rabbits were randomly divided into two groups: one group with intact corneal epithelium and another group without intact corneal epithelium. In the later group, the corneal epithelium of the rabbit was scraped using mechanical elimination method. The corneal thickness was monitored continuously by ultrasonic pachymetry at several postmortem interval points in rabbits of the two groups. The changes of corneal thickness and postmortem interval were explored by relative regression analysis. Results The thickness of the cornea showed a strong non-linear correlation with the postmortem interval in the group with intact corneal epithelium. The group with intact corneal epithelium showed the correlation coefficient 0.922 and the group without intact corneal epithelium showed the correlation coefficient 0.822, respectively. Conclusion The corneal thickness measured by ultrasonic pachymetry shows a potential value for estimating early postmortem interval. The intact corneal epithelium is a crucial factor for the measurement of cornea thickness by ultrasonic pachymetry.

  11. Fundamentals and Applications of Ultrasonic Waves

    CERN Document Server

    Cheeke, J David N

    2012-01-01

    Designed specifically for newcomers to the field, this fully updated second edition begins with fundamentals and quickly advances beyond general wave concepts into an in-depth treatment of ultrasonic waves in isotropic media. Focusing on the physics of acoustic waves, their propagation, technology, and applications, this accessible overview of ultrasonics includes accounts of viscoelasticity and multiple scattering. It examines new technologies, including atomic force acoustic microscopy, lasers, micro-acoustics, and nanotechnology. In addition, it highlights both direct and indirect applicati

  12. Recent advances in computational structural reliability analysis methods

    Science.gov (United States)

    Thacker, Ben H.; Wu, Y.-T.; Millwater, Harry R.; Torng, Tony Y.; Riha, David S.

    1993-01-01

    The goal of structural reliability analysis is to determine the probability that the structure will adequately perform its intended function when operating under the given environmental conditions. Thus, the notion of reliability admits the possibility of failure. Given the fact that many different modes of failure are usually possible, achievement of this goal is a formidable task, especially for large, complex structural systems. The traditional (deterministic) design methodology attempts to assure reliability by the application of safety factors and conservative assumptions. However, the safety factor approach lacks a quantitative basis in that the level of reliability is never known and usually results in overly conservative designs because of compounding conservatisms. Furthermore, problem parameters that control the reliability are not identified, nor their importance evaluated. A summary of recent advances in computational structural reliability assessment is presented. A significant level of activity in the research and development community was seen recently, much of which was directed towards the prediction of failure probabilities for single mode failures. The focus is to present some early results and demonstrations of advanced reliability methods applied to structural system problems. This includes structures that can fail as a result of multiple component failures (e.g., a redundant truss), or structural components that may fail due to multiple interacting failure modes (e.g., excessive deflection, resonate vibration, or creep rupture). From these results, some observations and recommendations are made with regard to future research needs.

  13. 超声波流量检测新方法研究%Research on New Method for Detection of Ultrasonic Flow

    Institute of Scientific and Technical Information of China (English)

    杨秋菊

    2013-01-01

      This paper analyses the time-difference detection method of ultrasonic flow and proposes a noves signal processing way based on the integral method and zero crossing detection technology, which aims to reduce the power consumption and avoids the complexity of signal processing. Inaddition, the paper also combines the timing procedure design and puts forward a effective measure to achieve low power consumption of ultrasonic flow detection.%  文章通过分析超声波流量的时差式检测方法,创新地采用了基于积分法及过零检测技术,提出了基于此方法的信号处理方式,达到了降低整机功耗的目的,规避了复杂的信号处理。此外,文章还结合了对时序工作方面的设计,提出了一种有效的措施来达到对超声波流量低功耗检测的目的。

  14. 超声有限幅度法检测混凝土孔洞缺陷%Characterization of Concrete Hole Defects by Ultrasonic Finite Amplitude Method

    Institute of Scientific and Technical Information of China (English)

    陈军; 黄灿; 王豪

    2016-01-01

    超声有限幅度法是用超声波在受损材料中传播时产生的高次谐波与材料非线性参数的关系,来检测材料损伤的方法,其在材料的微观损伤检测中已有较成熟的应用。用有限幅度法检测含有不同大小孔洞缺陷的混凝土试块,检测结果表明,非线性参数能反映出混凝土孔洞缺陷的大小。%The finite amplitude method is a nonlinear ultrasonic technique that uses the relation of higher order ultrasonic harmonics with nonlinear parameters of damaged materials and structures for the characterization of material defects,which has been more often used in material microscopic damage diagnostics.The finite amplitude method is used in detecting concrete with different sizes of holes.The results show that the nonlinear parameter can sensitively reflect the extent of the hole defect.

  15. Arrangement for the electronic ultrasonic leak testing

    International Nuclear Information System (INIS)

    The electronic equipment serves to receive ultrasonic signals, originated by a fluid (for example He) that under high pressure flows out of an opening (box cap-leak testing method). The ultrasonic signal is received by a microphone, amplified, and then led to an average signal value circuit, which together with a logic circuit locates the failed boxes. (DG)

  16. Contributions regarding chemical composition variation in ultrasonic field overlaying welding

    Science.gov (United States)

    Amza, Gh; Petrescu, V.; Niţoi, D. F.; Amza, C. Gh; Dimitrescu, A.; Apostolescu, Z.

    2016-08-01

    Paper presents a new reconditioning method based on ultrasonic field and analyses the modificated structure composition in three zone: filler material, thermal influenced zone, and base material. Also, chemical composition variation as a result of ultrasonic wave influence is studied besides the ultrasonic wave influence on dilution process.

  17. Study on the method of ultrasonic measurement for gastric emptying function%胃排空功能超声测定方法的研究

    Institute of Scientific and Technical Information of China (English)

    杨舒萍; 林丽卿; 洪理伟; 蔡晓菡; 刘彦; 沈浩霖

    2013-01-01

    Objective To search one ultrasonic method which could evaluate gastric emptying function accurately.Methods The gastric emptying time of 74 normal volunteers were measured by radioisotope scanning and different ultrasonic methods which including gastric antrum area,gastric antrum volume and whole gastric cylinder method.Results The gastric emptying time measured by whole gastric cylinder method related best with those measured by radioisotope scanning (r =0.79).The gastric emptying time was no significant difference between the cylinder method and radionuclide scanning (P >0.05).Compared with radionuclide scanning,those measured by gastric antrum area and gastric antrum volume had significant differences.Conclusions The whole gastric cylinder method can accurately reflect the gastric emptying function.%目的 探讨超声技术准确测定胃排空功能的方法.方法 分别采用胃窦面积法、胃窦体积法和全胃圆柱体法对74例正常志愿者的胃排空时间进行测定,并与核素扫描测定结果比较,准确反映胃排空功能.结果 应用全胃圆柱体法超声所测定的胃排空时间与核素扫描测定的胃排空时间相关性最好(r=0.79),差异无统计学意义(P>0.05).胃窦面积法、胃窦体积法测得的胃排空时间与核素扫描对比差异均有统计学意义(P<0.05).结论 应用超声全胃圆柱体法能够准确测定胃排空功能.

  18. Advanced methods for the study of PWR cores

    International Nuclear Information System (INIS)

    This document gathers the transparencies presented at the 6. technical session of the French nuclear energy society (SFEN) in October 2003. The transparencies of the annual meeting are presented in the introductive part: 1 - status of the French nuclear park: nuclear energy results, management of an exceptional climatic situation: the heat wave of summer 2003 and the power generation (J.C. Barral); 2 - status of the research on controlled thermonuclear fusion (J. Johner). Then follows the technical session about the advanced methods for the study of PWR reactor cores: 1 - the evolution approach of study methodologies (M. Lambert, J. Pelet); 2 - the point of view of the nuclear safety authority (D. Brenot); 3 - the improved decoupled methodology for the steam pipe rupture (S. Salvatores, J.Y. Pouliquen); 4 - the MIR method for the pellet-clad interaction (renovated IPG methodology) (E. Baud, C. Royere); 5 - the improved fuel management (IFM) studies for Koeberg (C. Cohen); 6 - principle of the methods of accident study implemented for the European pressurized reactor (EPR) (F. Foret, A. Ferrier); 7 - accident studies with the EPR, steam pipe rupture (N. Nicaise, S. Salvatores); 8 - the co-development platform, a new generation of software tools for the new methodologies (C. Chauliac). (J.S.)

  19. Ultrasonic velocity and absorption study of binary mixtures of cyclohexane with acrylonitrile by interferometric method at different frequencies

    Science.gov (United States)

    Pawar, N. R.; Chimankar, O. P.; Bhandakkar, V. D.; Padole, N. N.

    2012-12-01

    The ultrasonic velocity (u), absorption (α), density (ρ), and viscosity (η) has been measured at different frequencies (1MHz to 10MHz) in the binary mixtures of cyclohexane with acrylonitriile over the entire range of composition at temperature 303K. Vander Waal's constant (b), adiabatic compressibility (βa), acoustic impedance (Z), molar volume (V), free length (Lf), free volume, internal pressure, intermolecular radius and relative association have been also calculated. A special application for acrylonitrile is in the manufacture of carbon fibers. These are produced by paralysis of oriented poly acrylonitrile fibers and are used to reinforce composites for high-performance applications in the aircraft, defense and aerospace industries. Other applications of acrylonitrile are in the production of fatty amines, ion exchange resins and fatty amine amides used in cosmetics, adhesives, corrosion inhibitors and water-treatment resins. Cyclohexane derivatives can be used for the synthesis of pharmaceuticals, dyes, herbicides, plant growth regulator, plasticizers, rubber chemicals, nylon, cyclamens and other organic compounds. In the view of these extensive applications of acrylonitrile and cyclohexane in the engineering process, textile and pharmaceutical industries present study provides qualitative information regarding the nature and strength of interaction in the liquid mixtures through derive parameters from ultrasonic velocity and absorption measurement.

  20. Ultrasonic velocity and absorption study of binary mixtures of cyclohexane with acrylonitrile by interferometric method at different frequencies

    International Nuclear Information System (INIS)

    The ultrasonic velocity (u), absorption (α), density (ρ), and viscosity (η) has been measured at different frequencies (1MHz to 10MHz) in the binary mixtures of cyclohexane with acrylonitriile over the entire range of composition at temperature 303K. Vander Waal's constant (b), adiabatic compressibility (βa), acoustic impedance (Z), molar volume (V), free length (Lf), free volume, internal pressure, intermolecular radius and relative association have been also calculated. A special application for acrylonitrile is in the manufacture of carbon fibers. These are produced by paralysis of oriented poly acrylonitrile fibers and are used to reinforce composites for high-performance applications in the aircraft, defense and aerospace industries. Other applications of acrylonitrile are in the production of fatty amines, ion exchange resins and fatty amine amides used in cosmetics, adhesives, corrosion inhibitors and water-treatment resins. Cyclohexane derivatives can be used for the synthesis of pharmaceuticals, dyes, herbicides, plant growth regulator, plasticizers, rubber chemicals, nylon, cyclamens and other organic compounds. In the view of these extensive applications of acrylonitrile and cyclohexane in the engineering process, textile and pharmaceutical industries present study provides qualitative information regarding the nature and strength of interaction in the liquid mixtures through derive parameters from ultrasonic velocity and absorption measurement.

  1. Comparison of advanced iterative reconstruction methods for SPECT/CT

    International Nuclear Information System (INIS)

    Aim: Corrective image reconstruction methods which produce reconstructed images with improved spatial resolution and decreased noise level became recently commercially available. In this work, we tested the performance of three new software packages with reconstruction schemes recommended by the manufacturers using physical phantoms simulating realistic clinical settings. Methods: A specially designed resolution phantom containing three 99mTc lines sources and the NEMA NU-2 image quality phantom were acquired on three different SPECT/CT systems (General Electrics Infinia, Philips BrightView and Siemens Symbia T6). Measurement of both phantoms was done with the trunk filled with a 99mTc-water solution. The projection data were reconstructed using the GE's Evolution for Bone registered, Philips Astonish registered and Siemens Flash3D registered software. The reconstruction parameters employed (number of iterations and subsets, the choice of post-filtering) followed theses recommendations of each vendor. These results were compared with reference reconstructions using the ordered subset expectation maximization (OSEM) reconstruction scheme. Results: The best results (smallest value for resolution, highest percent contrast values) for all three packages were found for the scatter corrected data without applying any post-filtering. The advanced reconstruction methods improve the full width at half maximum (FWHM) of the line sources from 11.4 to 9.5 mm (GE), from 9.1 to 6.4 mm (Philips), and from 12.1 to 8.9 mm (Siemens) if no additional post filter was applied. The total image quality control index measured for a concentration ratio of 8:1 improves for GE from 147 to 189, from 179. to 325 for Philips and from 217 to 320 for Siemens using the reference method for comparison. The same trends can be observed for the 4:1 concentration ratio. The use of a post-filter reduces the background variability approximately by a factor of two, but deteriorates significantly the

  2. Enhanced Sonocatalytic Degradation of Rhodamine B by Graphene-TiO2 Composites Synthesized by an Ultrasonic-Assisted Method%Enhanced Sonocatalytic Degradation of Rhodamine B by Graphene-TiO2 Composites Synthesized by an Ultrasonic-Assisted Method

    Institute of Scientific and Technical Information of China (English)

    ZHU Lei; Trisha GHOSH; Chong-Yeon PARK; MENG Ze-Da; OH Won-Chun

    2012-01-01

    A series of graphene-TiO2 composites was fabricated from graphene oxide and titanium n-butoxide (TNB) by an ultrasonic-assisted method.The structure and composition of the nanocomposites were characterized by Raman spectroscopy,BET surface area measurements,X-ray diffraction,transmission electron microscopy,and ultraviolet-visible absorption spectroscopy.The average size of the TiO2 nanoparticles on the graphene nanosheets was controlled at around 10-15 nm without using surfactant,which is attributed to the pyrolysis and condensation of dissolved TNB into TiO2 by ultrasonic irradiation.The catalytic activity of the composites under ultrasonic irradiation was determined using a rhodamine B (RhB) solution.The graphene-TiO2 composites possessed a high specific surface area,which increased the decolorization rate for RhB solution.This is because the graphene and TiO2 nanoparticles in the composites interact strongly,which enhances the photoelectric conversion of TiO2 by reducing the recombination ofphotogenerated electron-hole pairs.

  3. Ultrasonic Evaluation and Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, Susan L.; Anderson, Michael T.; Diaz, Aaron A.; Larche, Michael R.; Prowant, Matthew S.; Cinson, Anthony D.

    2015-10-01

    Ultrasonic evaluation of materials for material characterization and flaw detection is as simple as manually moving a single-element probe across a speci-men and looking at an oscilloscope display in real time or as complex as automatically (under computer control) scanning a phased-array probe across a specimen and collecting encoded data for immediate or off-line data analyses. The reliability of the results in the second technique is greatly increased because of a higher density of measurements per scanned area and measurements that can be more precisely related to the specimen geometry. This chapter will briefly discuss applications of the collection of spatially encoded data and focus primarily on the off-line analyses in the form of data imaging. Pacific Northwest National Laboratory (PNNL) has been involved with as-sessing and advancing the reliability of inservice inspections of nuclear power plant components for over 35 years. Modern ultrasonic imaging techniques such as the synthetic aperture focusing technique (SAFT), phased-array (PA) technolo-gy and sound field mapping have undergone considerable improvements to effec-tively assess and better understand material constraints.

  4. Production and characterization of submicron hematite (α−Fe{sub 2}O{sub 3}) particles by ultrasonic spray pyrolysis method

    Energy Technology Data Exchange (ETDEWEB)

    Kırcı, Burak; Ebin, Burçak; Gürmen, Sebahattin [Department of Metallurgical and Materials Engineering, Istanbul Technical University Istanbul (Turkey)

    2013-12-16

    The ultrasonic spray pyrolysis (USP) method has been used to prepare submicron hematite (α−Fe{sub 2}O{sub 3}) particles using two different industrial pickling solutions of iron chloride (41 g/L FeCl{sub 2} and 54 g/L FeCl{sub 3}) Particles were obtained by thermal decomposition of generated aerosols from precursor solutions using 1.7 MHz ultrasonic atomizer. Reaction temperature was set up at 800 °C and aerosol droplets were carried into the heated zone by 0.7 L/min air flow rate. X-Ray Diffraction (XRD) studies were used to determine the crystal structure and crystallite size of the particles. Results indicate that patterns correspond to hematite phase with rhombohedral crystal structure (space group: R3c). The crystallite sizes of particles prepared from FeCl{sub 2} and FeCl{sub 3} solutions that were calculated from Scherrer equation are 59 and 33 nm, respectively. Scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) investigations give detailed information about particle size, morphology and composition. SEM micrographs show that hematite nanoparticles aggregate and formed spherical secondary particles in submicron range.

  5. Quantitative ultrasonic evaluation of mechanical properties of engineering materials

    Science.gov (United States)

    Vary, A.

    1978-01-01

    Current progress in the application of ultrasonic techniques to nondestructive measurement of mechanical strength properties of engineering materials is reviewed. Even where conventional NDE techniques have shown that a part is free of overt defects, advanced NDE techniques should be available to confirm the material properties assumed in the part's design. There are many instances where metallic, composite, or ceramic parts may be free of critical defects while still being susceptible to failure under design loads due to inadequate or degraded mechanical strength. This must be considered in any failure prevention scheme that relies on fracture analysis. This review will discuss the availability of ultrasonic methods that can be applied to actual parts to assess their potential susceptibility to failure under design conditions.

  6. New method based on combining ultrasonic assisted miniaturized matrix solid-phase dispersion and homogeneous liquid-liquid extraction for the determination of some organochlorinated pesticides in fish

    International Nuclear Information System (INIS)

    Highlights: → Ultrasonic assisted miniaturized matrix solid-phase dispersion combined with HLLE was developed as a new method for the extraction of OCPs in fish. → The goal of this combination was to enhance the selectivity of HLLE procedure and to extend its application in biological samples. → This method proposed the advantages of good detection limits, lower consumption of reagents, and does not need any special instrumentation. - Abstract: In this study, ultrasonic assisted miniaturized matrix solid-phase dispersion (US-MMSPD) combined with homogeneous liquid-liquid extraction (HLLE) has been developed as a new method for the extraction of organochlorinated pesticides (OCPs) in fish prior to gas chromatography with electron capture detector (GC-ECD). In the proposed method, OCPs (heptachlor, aldrin, DDE, DDD, lindane and endrin) were first extracted from fish sample into acetonitrile by US-MMSPD procedure, and the extract was then used as consolute solvent in HLLE process. Optimal condition for US-MMSPD step was as follows: volume of acetonitrile, 1.5 mL; temperature of ultrasound, 40 deg. C; time of ultrasound, 10 min. For HLLE step, optimal results were obtained at the following conditions: volume of chloroform, 35 μL; volume of aqueous phase, 1.5 mL; volume of double distilled water, 0.5 mL; time of centrifuge, 10 min. Under the optimum conditions, the enrichment factors for the studied compounds were obtained in the range of 185-240, and the overall recoveries were ranged from 39.1% to 81.5%. The limits of detection were 0.4-1.2 ng g-1 and the relative standard deviations for 20 ng g-1 of the OCPs, varied from 3.2% to 8% (n = 4). Finally, the proposed method has been successfully applied to the analysis of the OCPs in real fish sample, and satisfactory results were obtained.

  7. New method based on combining ultrasonic assisted miniaturized matrix solid-phase dispersion and homogeneous liquid-liquid extraction for the determination of some organochlorinated pesticides in fish

    Energy Technology Data Exchange (ETDEWEB)

    Rezaei, Farahnaz [Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Narmak, Tehran 16846 (Iran, Islamic Republic of); Hosseini, Mohammad-Reza Milani, E-mail: drmilani@iust.ac.ir [Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Narmak, Tehran 16846 (Iran, Islamic Republic of); Electroanalytical Chemistry Research Center, Iran University of Science and Technology, Narmak, Tehran 16846 (Iran, Islamic Republic of)

    2011-09-30

    Highlights: {yields} Ultrasonic assisted miniaturized matrix solid-phase dispersion combined with HLLE was developed as a new method for the extraction of OCPs in fish. {yields} The goal of this combination was to enhance the selectivity of HLLE procedure and to extend its application in biological samples. {yields} This method proposed the advantages of good detection limits, lower consumption of reagents, and does not need any special instrumentation. - Abstract: In this study, ultrasonic assisted miniaturized matrix solid-phase dispersion (US-MMSPD) combined with homogeneous liquid-liquid extraction (HLLE) has been developed as a new method for the extraction of organochlorinated pesticides (OCPs) in fish prior to gas chromatography with electron capture detector (GC-ECD). In the proposed method, OCPs (heptachlor, aldrin, DDE, DDD, lindane and endrin) were first extracted from fish sample into acetonitrile by US-MMSPD procedure, and the extract was then used as consolute solvent in HLLE process. Optimal condition for US-MMSPD step was as follows: volume of acetonitrile, 1.5 mL; temperature of ultrasound, 40 deg. C; time of ultrasound, 10 min. For HLLE step, optimal results were obtained at the following conditions: volume of chloroform, 35 {mu}L; volume of aqueous phase, 1.5 mL; volume of double distilled water, 0.5 mL; time of centrifuge, 10 min. Under the optimum conditions, the enrichment factors for the studied compounds were obtained in the range of 185-240, and the overall recoveries were ranged from 39.1% to 81.5%. The limits of detection were 0.4-1.2 ng g{sup -1} and the relative standard deviations for 20 ng g{sup -1} of the OCPs, varied from 3.2% to 8% (n = 4). Finally, the proposed method has been successfully applied to the analysis of the OCPs in real fish sample, and satisfactory results were obtained.

  8. A rapid and sensitive method to determine tacrolimus in rat whole blood using liquid-liquid extraction with mild temperature ultrasonication and LC-MS/MS.

    Science.gov (United States)

    Park, Jun Seo; Cho, Ha Ra; Kang, Myung Joo; Choi, Yong Seok

    2016-01-01

    Tacrolimus (TAC) is an immunosuppressant widely used in organ transplantation, but its extremely low aqueous solubility causes poor intestinal absorption. There have been efforts to develop an alternative TAC formulation with an improved dissolution rate and oral bioavailability (BA), and the development of a rapid and sensitive analytical method for its in vivo pharmacokinetic study is an essential prerequisite. Thus, here, we develop a novel method to determine TAC in rat whole blood based on liquid chromatography and tandem mass spectrometry, and liquid-liquid extraction (LLE) with mild temperature ultrasonication. For rapid and efficient separation of TAC from other hydrophobic compounds, a C8 column was chosen with isocratic mobile phase elution. With the help of the high specificity and the high sensitivity of multiple reaction monitoring in positive ion mode, the present method showed good performance including specificity, linearity (r(2) ≥ 0.996 within 1-200 ng/mL), sensitivity (the lower limit of quantitation at 1 ng/mL), intra- and inter-day accuracy (88.7-104.5 %) and precision (≤10.3 %), and recovery (94.7-102.6 %). Also, the stability of TAC and ascomycin, the internal standard, in rat whole blood was confirmed before and after the sample preparation. The validated method was satisfactorily applied to a pharmacokinetic study to determine TAC in rat whole blood following oral administration of the marketed product (Prograf(®), Astellas Pharma). In the present study, LLE with mild temperature ultrasonication was successfully expanded to the determination of a drug from whole blood or plasma for the first time. Therefore, the present method can contribute to the rapid in vivo evaluation of novel TAC formulations, and will be able to contribute to the development of TAC formulations with a higher dissolution rate and a higher BA. PMID:26589688

  9. Radiation Mitigation Methods for Advanced Readout Array Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA is interested in the development of advanced instruments and instrument components for planetary science missions. Specifically, an area of importance in...

  10. Introduction of measurement techniques in ultrasonic electronics: Basic principles and recent trends

    Science.gov (United States)

    Mizutani, Koichi; Wakatsuki, Naoto; Ebihara, Tadashi

    2016-07-01

    Measurement — the act of measuring physical properties that we perform — has the potential to contribute to the successful advancement of sciences and society. To open doors in physics and other sciences, various measurement methods and related applications have been developed, and ultrasound has remained a useful probe, power source, and interesting measurement object for the past two centuries. In this paper, we first summarize the basic principles of ultrasound from the viewpoint of measurement techniques for readers who just have started studying or are interested in the field of ultrasonic electronics. Moreover, we also introduce recent studies — ultrasonic properties of materials, measurement techniques, piezoelectric devices, nonlinear acoustics, biomedical ultrasound, and ocean acoustics — and their trends related to measurement techniques in ultrasonic electronics to provide some ideas for related applications.

  11. Enhancement of crack detection in stud bolts of nuclear reactor by ultrasonic technique

    International Nuclear Information System (INIS)

    The stud bolt is one of crucial parts for safety of reactor vessels in nuclear power plants. Crack initiation and propagation were reported in stud bolts using closure of reactor vessel and head. Stud bolts are inspected by ultrasonic technique during overhaul periodically for the prevention of stud bolt failure and radioactive leakage from nuclear reactor. In conventional ultrasonic testing for inspection of stud bolts, crack was detected by using shadow effect. It takes too much time to inspect stud bolt 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 and the advanced ultrasonic phased array technique were introduced for inspect stud bolts. The signal processing technique provides removing spurious signal reflected from every oblique surfaces of thread and enhances detectability of defects. The phased array technique provides fast inspection and can be applied for structure of complex shape. There are sector scanning and linear scanning methods in phased array technique, and these scanning methods were applied to inspect stud bolt and detectability was investigated. (author)

  12. Effect of acoustic field parameters on arc acoustic binding during ultrasonic wave-assisted arc welding.

    Science.gov (United States)

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

    2016-03-01

    As a newly developed arc welding method, power ultrasound has been successfully introduced into arc and weld pool during ultrasonic wave-assisted arc welding process. The advanced process for molten metals can be realized by utilizing additional ultrasonic field. Under the action of the acoustic wave, the plasma arc as weld heat source is regulated and its characteristics make an obvious change. Compared with the conventional arc, the ultrasonic wave-assisted arc plasma is bound significantly and becomes brighter. To reveal the dependence of the acoustic binding force on acoustic field parameters, a two-dimensional acoustic field model for ultrasonic wave-assisted arc welding device is established. The influences of the radiator height, the central pore radius, the radiator radius, and curvature radius or depth of concave radiator surface are discussed using the boundary element method. Then the authors analyze the resonant mode by this relationship curve between acoustic radiation power and radiator height. Furthermore, the best acoustic binding ability is obtained by optimizing the geometric parameters of acoustic radiator. In addition, three concave radiator surfaces including spherical cap surface, paraboloid of revolution, and rotating single curved surface are investigated systematically. Finally, both the calculation and experiment suggest that, to obtain the best acoustic binding ability, the ultrasonic wave-assisted arc welding setup should be operated under the first resonant mode using a radiator with a spherical cap surface, a small central pore, a large section radius and an appropriate curvature radius. PMID:26558995

  13. Effect of acoustic field parameters on arc acoustic binding during ultrasonic wave-assisted arc welding.

    Science.gov (United States)

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

    2016-03-01

    As a newly developed arc welding method, power ultrasound has been successfully introduced into arc and weld pool during ultrasonic wave-assisted arc welding process. The advanced process for molten metals can be realized by utilizing additional ultrasonic field. Under the action of the acoustic wave, the plasma arc as weld heat source is regulated and its characteristics make an obvious change. Compared with the conventional arc, the ultrasonic wave-assisted arc plasma is bound significantly and becomes brighter. To reveal the dependence of the acoustic binding force on acoustic field parameters, a two-dimensional acoustic field model for ultrasonic wave-assisted arc welding device is established. The influences of the radiator height, the central pore radius, the radiator radius, and curvature radius or depth of concave radiator surface are discussed using the boundary element method. Then the authors analyze the resonant mode by this relationship curve between acoustic radiation power and radiator height. Furthermore, the best acoustic binding ability is obtained by optimizing the geometric parameters of acoustic radiator. In addition, three concave radiator surfaces including spherical cap surface, paraboloid of revolution, and rotating single curved surface are investigated systematically. Finally, both the calculation and experiment suggest that, to obtain the best acoustic binding ability, the ultrasonic wave-assisted arc welding setup should be operated under the first resonant mode using a radiator with a spherical cap surface, a small central pore, a large section radius and an appropriate curvature radius.

  14. Physical Characterization of Solid-Liquid Slurries at High Weight Fractions Using Optical and Ultrasonic Methods. Final Report

    International Nuclear Information System (INIS)

    Remediation of highly radioactive waste is a major technical and programmatic challenge for the DOE. Rapid, on-line physical characterization of highly concentrated slurries is required for the safe and efficient remediation of 90 million gallons of high level radioactive waste (HLW), sodium bearing waste, and mixed waste. The research presented here, describes a collaborative effort between Pacific Northwest National Laboratory (PNNL) and the University of Washington to directly address the need for rapid on-line characterization of the physical properties of HLW slurries during all phases of the remediation process, from in-tank characterization of sediments to monitoring of the concentration, particle size, and degree of agglomeration and gelation of slurries during transport. Near-surface characterization of the slurry flow in the particle size range from nanometer to micrometer is examined using optical low coherence reflectometry. Volumetric characterization at depths in the slurry flow, up to several centimeters in the particle size range from the micrometer to millimeter, is realized by utilizing ultrasonic backscatter and diffuses fields. One of the strengths, the teaming up of significant talents in both experimental and theoretical optics (University of Washington) and in ultrasonics (Pacific Northwest National Laboratory (PNNL)) provides a synergistic approach to integrate these complimentary techniques. One of the benefits of this combined approach is the physical characterization of HLW over a concentration and particle size range that is broader than can be achieved with today's technology. This will avoid a costly increase in waste stream volume due to excess dilution, and will lessen chance of plugging pipes that could shut down expensive processing lines.

  15. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; use of a modified ultrasonic nebulizer for the analysis of low ionic-strength water by inductively coupled optical emission spectrometry

    Science.gov (United States)

    Harris, Carl M.; Litteral, Charles J.; Damrau, Donna L.

    1997-01-01

    The U.S. Geological Survey National Water Quality Laboratory has developed a method for the determination of dissolved calcium, iron, magnesium, manganese, silica, and sodium using a modified ultrasonic nebulizer sample-introduction system to an inductively coupled plasma-optical emission spectrometer. The nebulizer's spray chamber has been modified to avoid carryover and memory effects common in some conventional ultrasonic designs. The modified ultrasonic nebulizer is equipped with a high-speed rinse cycle to remove previously analyzed samples from the spray chamber without excessive flush times. This new rinse cycle decreases sample washout times by reducing carryover and memory effects from salt or analytes in previously analyzed samples by as much as 45 percent. Plasma instability has been reduced by repositioning the argon carrier gas inlet on the spray chamber and by directly pumping waste from the chamber, instead of from open drain traps, thereby maintaining constant pressure to the plasma. The ultrasonic nebulizer improves signal intensities, which are 8 to 16 times greater than for a conventional cross-flow pneumatic nebulizer, without being sensitive to clogging from salt buildup as in cross-flow nebulizers. Detection limits for the ultrasonic nebulizer are 4 to 18 times less than detection limits achievable using a cross-flow pneumatic nebulizer, with equivalent sample analysis time.

  16. Ultrasonic testing device

    International Nuclear Information System (INIS)

    The ultrasonic testing system serves to inspect welds and the adjoining heat-affected zones on reactor pressure vessels. The three-oscillator search unit has got either two external emitter crystal oscillators simultaneously loaded and an internal receiver crystal oscillator of equal width or vice versa. The inspection path is run through meanderingly. With the search unit there is succeeded to do the inspection by SEL technique, by SE technique with shear waves or by tandem technique. Loading of the oscillators is done with a time-multiplex method. (RW)

  17. Ultrasonic Determination Of Recrystallization

    Science.gov (United States)

    Generazio, Edward R.

    1988-01-01

    State of recrystallization identified. Measurement of ultrasonic attenuation shows promise as means of detecting recrystallization in metal. Technique applicable to real-time acoustic monitoring of thermomechanical treatments. Starting with work-hardened material, one ultrasonically determines effect of annealing, using correlation between ultrasonic attenuation and temperature.

  18. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H.; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue ...

  19. Application advances of microwave and ultrasonic in tungsten metallurgy%微波及超声波在钨冶金中的研究进展

    Institute of Scientific and Technical Information of China (English)

    曾青云; 张勇; 帅庚未

    2014-01-01

    The application processes with microwave and ultrasonic technology in tungsten metallurgy is introduced. The application of microwave in tungsten metallurgy includes the promotion of the ore leaching of scheelite and wolframite, as well as the synthesis of tungsten-containing compounds, the sintering of the tungsten -containing compounds and the thermal decomposition preparation of tungsten trioxide. The application of ultrasonic in metallurgy of tungsten contains the enforcement of the extraction of tungsten-containing compounds and crystallization of APT , assisted preparation of tungsten-containing compounds and industrial testing. The application of microwave and ultrasonic technology in tungsten metallurgy are becoming increasingly prevalent and far-reaching.%概述近年微波及超声波在钨冶金生产工艺中的应用研究进展,简介其应用工艺和技术。主要从微波在钨冶金中应用:促进黑、白钨矿浸出;促进含钨化合物合成;烧结含钨化合物与热分解制备三氧化钨;超声波在钨冶金中应用:强化钨矿浸出及仲钨酸铵结晶;辅助制备含钨化合物;工业探伤应用等领域进行介绍。微波及超声波技术在钨冶金中应用将越来越广泛和深入。

  20. Methods for integrating optical fibers with advanced aerospace materials

    Science.gov (United States)

    Poland, Stephen H.; May, Russell G.; Murphy, Kent A.; Claus, Richard O.; Tran, Tuan A.; Miller, Mark S.

    1993-07-01

    Optical fibers are attractive candidates for sensing applications in near-term smart materials and structures, due to their inherent immunity to electromagnetic interference and ground loops, their capability for distributed and multiplexed operation, and their high sensitivity and dynamic range. These same attributes also render optical fibers attractive for avionics busses for fly-by-light systems in advanced aircraft. The integration of such optical fibers with metal and composite aircraft and aerospace materials, however, remains a limiting factor in their successful use in such applications. This paper first details methods for the practical integration of optical fiber waveguides and cable assemblies onto and into materials and structures. Physical properties of the optical fiber and coatings which affect the survivability of the fiber are then considered. Mechanisms for the transfer of the strain from matrix to fiber for sensor and data bus fibers integrated with composite structural elements are evaluated for their influence on fiber survivability, in applications where strain or impact is imparted to the assembly.

  1. Regenerative medicine: advances in new methods and technologies.

    Science.gov (United States)

    Park, Dong-Hyuk; Eve, David J

    2009-11-01

    The articles published in the journal Cell Transplantation - The Regenerative Medicine Journal over the last two years reveal the recent and future cutting-edge research in the fields of regenerative and transplantation medicine. 437 articles were published from 2007 to 2008, a 17% increase compared to the 373 articles in 2006-2007. Neuroscience was still the most common section in both the number of articles and the percentage of all manuscripts published. The increasing interest and rapid advance in bioengineering technology is highlighted by tissue engineering and bioartificial organs being ranked second again. For a similar reason, the methods and new technologies section increased significantly compared to the last period. Articles focusing on the transplantation of stem cell lineages encompassed almost 20% of all articles published. By contrast, the non-stem cell transplantation group which is made up primarily of islet cells, followed by biomaterials and fetal neural tissue, etc. comprised less than 15%. Transplantation of cells pre-treated with medicine or gene transfection to prolong graft survival or promote differentiation into the needed phenotype, was prevalent in the transplantation articles regardless of the kind of cells used. Meanwhile, the majority of non-transplantation-based articles were related to new devices for various purposes, characterization of unknown cells, medicines, cell preparation and/or optimization for transplantation (e.g. isolation and culture), and disease pathology. PMID:19865067

  2. Advanced methods of quality control in nuclear fuel fabrication

    International Nuclear Information System (INIS)

    Under pressure of current economic and electricity market situation utilities implement more demanding fuel utilization schemes including higher burn ups and thermal rates, longer fuel cycles and usage of Mo fuel. Therefore, fuel vendors have recently initiated new R and D programmes aimed at improving fuel quality, design and materials to produce robust and reliable fuel. In the beginning of commercial fuel fabrication, emphasis was given to advancements in Quality Control/Quality Assurance related mainly to product itself. During recent years, emphasis was transferred to improvements in process control and to implementation of overall Total Quality Management (TQM) programmes. In the area of fuel quality control, statistical control methods are now widely implemented replacing 100% inspection. This evolution, some practical examples and IAEA activities are described in the paper. The paper presents major findings of the latest IAEA Technical Meetings (TMs) and training courses in the area with emphasis on information received at the TM and training course held in 1999 and other latest publications to provide an overview of new developments in process/quality control, their implementation and results obtained including new approaches to QC

  3. Delamination detection in composites by laser ultrasonics

    Science.gov (United States)

    Martarelli, M.; Chiariotti, P.; Pezzola, M.; Castellini, P.

    2014-05-01

    In this paper an application of Laser Ultrasonics (LU) is presented on laminate panels. The method exploits a high energy pulsed laser generating ultrasonic waves on the material where it impinges and laser Doppler Mach-Zehnder interferometer for measuring the ultrasonic waves propagating on the testing object. The laser-ultrasonic has been applied to a thin Carbon Fiber Reinforced Polymer (CFRP) test sample where two different depth delaminations have been created. It will be demonstrated that the measurement system is extremely sensitive to the propagation of the ultrasonic waves generated by the high energy pulsed laser source and to the multiple reflections caused by the delamination even when this latter is located in depth.

  4. Application of the Advanced Distillation Curve Method to Fuels for Advanced Combustion Engine Gasolines

    KAUST Repository

    Burger, Jessica L.

    2015-07-16

    © This article not subject to U.S. Copyright. Published 2015 by the American Chemical Society. Incremental but fundamental changes are currently being made to fuel composition and combustion strategies to diversify energy feedstocks, decrease pollution, and increase engine efficiency. The increase in parameter space (by having many variables in play simultaneously) makes it difficult at best to propose strategic changes to engine and fuel design by use of conventional build-and-test methodology. To make changes in the most time- and cost-effective manner, it is imperative that new computational tools and surrogate fuels are developed. Currently, sets of fuels are being characterized by industry groups, such as the Coordinating Research Council (CRC) and other entities, so that researchers in different laboratories have access to fuels with consistent properties. In this work, six gasolines (FACE A, C, F, G, I, and J) are characterized by the advanced distillation curve (ADC) method to determine the composition and enthalpy of combustion in various distillate volume fractions. Tracking the composition and enthalpy of distillate fractions provides valuable information for determining structure property relationships, and moreover, it provides the basis for the development of equations of state that can describe the thermodynamic properties of these complex mixtures and lead to development of surrogate fuels composed of major hydrocarbon classes found in target fuels.

  5. On measuring precision of thickness measurement with pulsed ultrasonic wave reflection method%浅谈脉冲式超声波反射法测厚的测量精度

    Institute of Scientific and Technical Information of China (English)

    蔡保山; 王俊立; 朱超阳

    2015-01-01

    本文介绍了脉冲式超声波反射法测厚原理,分析了影响测量精度的相关因素,提出了相应措施,通过试验验证,探讨了采用超声波检测仪进行测厚的应用范围及测量误差问题,为使用超声波检测仪进行高精度测厚提供了借鉴。%The principle of thickness measurement with pulsed ultrasonic wave reflection method is mainly introduced in this paper.Related factors affecting measurement precision are analyzed,and corresponding countermeasures are proposed. Application scope and measurement error problems of thickness measurement with ultrasonic detector are discussed through practical experiment.It provides reference for high-precision thickness measurement with ultrasonic detector.

  6. Electrochemical test methods for advanced battery and semiconductor technology

    Science.gov (United States)

    Hsu, Chao-Hung

    This dissertation consists of two studies. The first study was the evaluation of metallic materials for advanced lithium ion batteries and the second study was the determination of the dielectric constant k for the low-k materials. The advanced lithium ion battery is miniature for implantable medical devices and capable of being recharged from outside of the body using magnetic induction without physical connections. The stability of metallic materials employed in the lithium ion battery is one of the major safety concerns. Three types of materials---Pt-Ir alloy, Ti alloys, and stainless steels---were evaluated extensively in this study. The electrochemical characteristics of Pt-Ir alloy, Ti alloys, and stainless steels were evaluated in several types of battery electrolytes in order to determine the candidate materials for long-term use in lithium ion batteries. The dissolution behavior of these materials and the decomposition behavior of the battery electrolyte were investigated using the anodic potentiodynamic polarization (APP) technique. Lifetime prediction for metal dissolution was conducted using constant potential polarization (CPP) technique. The electrochemical impedance spectroscopy (EIS) technique was employed to investigate the metal dissolution behavior or the battery electrolyte decomposition at the open circuit potential (OCP). The scanning electron microscope (SEM) was used to observe the morphology changes after these tests. The effects of experimental factors on the corrosion behaviors of the metallic materials and stabilities of the battery electrolytes were also investigated using the 23 factorial design approach. Integration of materials having low dielectric constant k as interlayer dielectrics and/or low-resistivity conductors will partially solve the RC delay problem for the limiting performance of high-speed logic chips. The samples of JSR LKD 5109 material capped by several materials were evaluated by using EIS. The feasibility of using

  7. Development and Applications of Advanced Electronic Structure Methods

    Science.gov (United States)

    Bell, Franziska

    This dissertation contributes to three different areas in electronic structure theory. The first part of this thesis advances the fundamentals of orbital active spaces. Orbital active spaces are not only essential in multi-reference approaches, but have also become of interest in single-reference methods as they allow otherwise intractably large systems to be studied. However, despite their great importance, the optimal choice and, more importantly, their physical significance are still not fully understood. In order to address this problem, we studied the higher-order singular value decomposition (HOSVD) in the context of electronic structure methods. We were able to gain a physical understanding of the resulting orbitals and proved a connection to unrelaxed natural orbitals in the case of Moller-Plesset perturbation theory to second order (MP2). In the quest to find the optimal choice of the active space, we proposed a HOSVD for energy-weighted integrals, which yielded the fastest convergence in MP2 correlation energy for small- to medium-sized active spaces to date, and is also potentially transferable to coupled-cluster theory. In the second part, we studied monomeric and dimeric glycerol radical cations and their photo-induced dissociation in collaboration with Prof. Leone and his group. Understanding the mechanistic details involved in these processes are essential for further studies on the combustion of glycerol and carbohydrates. To our surprise, we found that in most cases, the experimentally observed appearance energies arise from the separation of product fragments from one another rather than rearrangement to products. The final chapters of this work focus on the development, assessment, and application of the spin-flip method, which is a single-reference approach, but capable of describing multi-reference problems. Systems exhibiting multi-reference character, which arises from the (near-) degeneracy of orbital energies, are amongst the most

  8. Comparative research on flavonoids extraction from Portulaca oleracea L.by ultrasonic method and microwave method%超声波法和微波法提取马齿苋中总黄酮的比较研究

    Institute of Scientific and Technical Information of China (English)

    翟硕莉

    2012-01-01

    采用超声波法和微波法分别对马齿苋中总黄酮的提取工艺进行了研究和对比分析.结果表明,超声波辅助萃取马齿苋黄酮的最佳工艺为料液比为1∶30,乙醇浓度为80%vol,作用温度为70℃,时间为30min,总黄酮萃取率为6.58%.微波辅助萃取马齿苋黄酮的最佳工艺为乙醇浓度为70%vol,微波功率为600W,作用时间为20min,料液比为1∶30,总黄酮萃取率7.65%.综合分析,在提取马齿苋中总黄酮的试验中,微波法萃取优于超声波法.%The extraction technology of flavonoids from Portulaca oleracea L. by ultrasonic method and microwave method were studied and comparatively analysed. The results showed that the optimum ultrasonic extraction conditions were the ratio of material to alcohol solvent (80%vol) 1:30, extraction temperature 70℃ and extraction time 30min and yield of flavonoids was 6.58% under the optimum conditions; and for microwave method, the optimum conditions were the microwave power 600W, extraction time 30min and the ratios of material to alcohol solvent (70%vol) 1:30, and the yield of flavonoids was 7.65%. The results indicated that microwave method was better than ultrasonic method.

  9. Optimization of Process Conditions of Total Flavonoids Extraction from Blueberry Leaves by Ultrasonic Method%超声波法提取蓝树莓叶黄酮类物质的工艺条件优化

    Institute of Scientific and Technical Information of China (English)

    张青峰; 张琴琴; 冯丽娟

    2012-01-01

    为明确提取蓝树莓叶中黄酮类物质的最佳工艺条件,利用超声波法提取蓝树莓叶中的总黄酮,研究超声时间、乙醇浓度、料液比3个因素对总黄酮提取率的影响,并通过正交试验确定了提取的最佳工艺条件.结果表明,蓝树莓最佳提取工艺为超声时间70 min,乙醇浓度50.0%,料液比1:20,总黄酮的提取率为23.178%.说明,该提取工艺简单、合理,可以用于测定蓝树莓总黄酮的含量.%To optimize the extraction conditions of total flavonoids from raspberry leaves by ultrasonic method. Total flavonoids was extracted from blueberry by ultrasonic method. The effects of four factors including ultrasonic power, ultrasonic time, ethanol concentration, solid-liquid ratio on the yield of total flavonoids were investigated. The optimum technological conditions of total flavonoids extraction were confirmed through the orthogonal test. The results showed that the optimum exaction technology conditions of blueberry were as follows; ultrasonic power for high stall, ultrasonic time of 70 min, 50% ethanol concentrationand solid-liquid ratio of 1 : 20, the yield of total flavonoids was 23. 178%. The extraction process was simple, reasonable, and could be used for determining the content of total flavonoids from raspberry.

  10. Ultrasonic examination techniques for multicouple thermoelectric subcomponents and assemblies: Status report

    Energy Technology Data Exchange (ETDEWEB)

    Cook, K.V.; McClung, R.W.; Simpson, W.A. Jr.; Cunningham, R.A. Jr.

    1986-09-01

    Since the early 1960s, the United States has been using radioisotope thermoelectric generators (RTGs), developed by the US Department of Energy and its predecessors, for a variety of environments including space. A recent concept in building RTGs uses modular components to allow for an advanced, lighter space mission generator that provides scaled power level outputs. The scalability feature of the modular isotopic thermoelectric generator (MITG) represents a major advance over earlier RTG designs. However, special problems are encountered in applying nondestructive testing methods because of the miniature size of parts that require inspection. This report describes the status of ultrasonic inspection methods being developed to examine the subcomponents and assemblies of the; MITG. The principal emphasis has been to evaluate various bonds between subcomponents using ultrasonic techniques that employ focused search units and a pulse-echo method.

  11. Inverse method for effects characterization from ultrasonic b-scan images; Caracterisation des defauts par une methode d'inversion lors d'un controle ultrasonore. Application au controle des defauts en paroi externe

    Energy Technology Data Exchange (ETDEWEB)

    Faur, M. [Paris-11 Univ., 91 - Orsay (France)

    1999-02-01

    In service inspections of French nuclear pressure water reactor vessels are carried out automatically in complete immersion from the inside by means of ultrasonic focused probes working in the pulse echo mode. Concern has been expressed about the capabilities of performing non destructive evaluation of the Outer Surface Defects (OSD), i.e. defects located in the vicinity of the outer surface of the inspected components. OSD are insonified by both a direct field that passes through the inner surface (water/steel) of the component containing the defect and a secondary field reflected from the outer surface. Consequently, the Bscan images, containing the signatures of such defects, are complicated and their interpretation is a difficult task. This work deals with extraction of the maximum available information for characterizing OSD from ultrasonic Bscan images. Our main objectives are to obtain the type of OSD and their geometric parameters by means of two specific inverse methods. The first method is used for the identification of the geometrical parameters of the equivalent planar OSD from segmented Bscan images. Ultrasonic equivalent defect sizing model-based methods may be used to size a defect in a material by obtaining a best-fit simple equivalent shape that matches the ultrasonic observed data. We illustrate the application of such an equivalent sizing OSD method that is based on a simplified direct model. The major drawback of this identification method, as used to date, is that only a part of the useful information contained into original Bscan image, i.e. segmented Bscan image, is used for defect characterization. Moreover, it requires the availability of defect classification information (i.e. if the defect is volumetric or planer, e. g. a crack or a lack of fusion), which, generally, may be as difficult to obtain as the defect parameters themselves. Therefore, we propose a parameter estimation method for extracting complementary information on the defect

  12. Sm-Doped Tio2 Nanoparticles with High Photocatalytic Activity for ARS Dye Under Visible Light Synthesized by Ultrasonic Assisted Sol-Gel Method

    Directory of Open Access Journals (Sweden)

    V. Aware Dinkar

    2016-05-01

    Full Text Available In this article series of nano crystalline Sm-doped TiO2 nano particles with various molar concentration of samarium were synthesized by modified ultrasonic assisted sol-gel method and calcined at 500°C for 2 h. The synthesized nanomaterials were characterized in details using XRD, TEM, XPS UV–vis DRS and BET analysis. The detailed photocatalytic activity results revealed that doped samples shows excellent photodegradation efficiency towards model pollutant Alizarin red-S (ARS and almost 93% dye degrades within 120 minutes. The highest photodegradation efficiency was noticed for 1mole % samarium doped sample at 50 mgL-1 of catalyst dose. The photocatalytic activity of synthesized nano particles were also compared with commercially available ZnO and TiO2 (Degussa, P-25 photocatalyst. It was found that synthesized nano materials showed enhanced photocatalytic efficiency than commercially available semiconducting photocatalyst.

  13. A New Inverse Method of Elastic Constants for a Fibre-Reinforced Composite Plate from Laser-Based Ultrasonic Lamb Waves

    Science.gov (United States)

    Yang, Jing; Cheng, Jian-Chun

    2001-12-01

    A new inverse method based on the wavelet transform and artificial neural networks (ANN) is presented to recover elastic constants of a fibre-reinforced composite plate from laser-based ultrasonic Lamb waves. The transient waveforms obtained by numerical simulations under different elastic constants are taken as the input of the ANN for training and learning. The wavelet transform is employed for extracting the eigenvectors from the raw Lamb wave signals so as to simplify the structure of the ANN. Then these eigenvectors are input to a multi-layer internally recurrent neural network with a back-propagation algorithm. Finally, the experimental waveforms are used as the input in the whole system to inverse elastic constants of the experimental material.

  14. A New Inverse Method of Elastic Constants for a Fibre-Reinforced Composite Plate from Laser-Based Ultrasonic Lamb Waves

    Institute of Scientific and Technical Information of China (English)

    杨京; 程建春

    2001-01-01

    A new inverse method based on the wavelet transform and artificial neural networks (ANN) is presented to recover elastic constants of a fibre-reinforced composite plate from laser-based ultrasonic Lamb waves. The transient waveforms obtained by numerical simulations under different elastic constants are taken as the input of the ANN for training and learning. The wavelet transform is employed for extracting the eigenvectors from the raw Lamb wave signals so as to simplify the structure of the ANN. Then these eigenvectors are input to a multi-layer internally recurrent neural network with a back-propagation algorithm. Finally, the experimental waveforms are used as the input in the whole system to inverse elastic constants of the experimental material.

  15. Atmospheric contamination during ultrasonic scaling

    NARCIS (Netherlands)

    Timmerman, MF; Menso, L; Steinfort, J; van Winkelhoff, AJ; van der Weijden, GA

    2004-01-01

    Objective: The aim of this study was to determine the microbial atmospheric contamination during initial periodontal treatment using a piezoelectric ultrasonic scaler in combination with either high-volume evacuation (HVE) or conventional dental suction (CDS). Methods: The study included 17 treatmen

  16. Improving Weld Quality by Arc-Excited Ultrasonic Treatment

    Institute of Scientific and Technical Information of China (English)

    张春雷; 吴敏生; 杜敬磊

    2001-01-01

    Ultrasonic treatment of the solidifying metal is a promising method for improving the quality of fusion welding. A method to combine the ultrasonic waves to the welding process using arc-excited ultrasonic emission, called arc-ultrasonic, was high frequency modulation of the arc-plasma. The effects of arc-ultrasonic on the weld including the fusion zone, the partially melted zone and the heat-affected zone are described. The arc-ultrasonic energy changes the weld microstructure. In the fusion zone, the primary dendrite arm spacing decreases significantly and more acicular ferrite appears. In the partially melted zone, a large amount of fine grains appear. In the heat-affected zone, the width of the tempered zone increases with increasing modulation frequency and the microstructure is refined. The results show that arc-ultrasonic is a new and effective way for improving weld quality.

  17. Ultrasonic testing of materials at level 2

    International Nuclear Information System (INIS)

    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

  18. Design of Ultrasonic Heat Meter Based on Quadrature Integration Method%基于相差积分法的超声波热量表设计

    Institute of Scientific and Technical Information of China (English)

    赵利国; 张金亮

    2012-01-01

    A high precision ultrasonic heat meter based on the quadrature integration method was designed,according to the household heat metering program for heating system.This paper mainly focuses on the principle and implementation of the quadrature Integration method ultrasonic flow measurement,as well as the calculation principles of heat and temperature measurement.The hardware test circuit was designed according to the measuring principle,and implemented based on the MSP430F437 control core.The battery-powered heat meters were designed to guarantee which can the long-term operation.Finally,after the on-line debugging and testing experiments on the entire system,this paper analyzed the error of the flow measurement.%针对供热系统分户式热量计量要求,设计了一种基于相差积分法的超声波热量表.主要介绍了相差积分法的超声波流量测量原理和实现方法,以及方案中所涉及到的热量计算、温度测量原理等;根据测量要求,设计了以MSP430F437为控制核心的硬件测试电路.由于热量表需用电池供电,为了保证热量表的长期运行,在硬件和软件上都进行了低功耗设计.最后,对整个系统进行了联机调试和测试实验,并对流量测量结果作了简单的误差分析.

  19. Characterization of full set material constants of piezoelectric materials based on ultrasonic method and inverse impedance spectroscopy using only one sample.

    Science.gov (United States)

    Li, Shiyang; Zheng, Limei; Jiang, Wenhua; Sahul, Raffi; Gopalan, Venkatraman; Cao, Wenwu

    2013-09-14

    The most difficult task in the characterization of complete set material properties for piezoelectric materials is self-consistency. Because there are many independent elastic, dielectric, and piezoelectric constants, several samples are needed to obtain the full set constants. Property variation from sample to sample often makes the obtained data set lack of self-consistency. Here, we present a method, based on pulse-echo ultrasound and inverse impedance spectroscopy, to precisely determine the full set physical properties of piezoelectric materials using only one small sample, which eliminated the sample to sample variation problem to guarantee self-consistency. The method has been applied to characterize the [001]C poled Mn modified 0.27Pb(In1/2Nb1/2)O3-0.46Pb(Mg1/3Nb2/3)O3-0.27PbTiO3 single crystal and the validity of the measured data is confirmed by a previously established method. For the inverse calculations using impedance spectrum, the stability of reconstructed results is analyzed by fluctuation analysis of input data. In contrast to conventional regression methods, our method here takes the full advantage of both ultrasonic and inverse impedance spectroscopy methods to extract all constants from only one small sample. The method provides a powerful tool for assisting novel piezoelectric materials of small size and for generating needed input data sets for device designs using finite element simulations.

  20. Advanced methods of continuum mechanics for materials and structures

    CERN Document Server

    Aßmus, Marcus

    2016-01-01

    This volume presents a collection of contributions on advanced approaches of continuum mechanics, which were written to celebrate the 60th birthday of Prof. Holm Altenbach. The contributions are on topics related to the theoretical foundations for the analysis of rods, shells and three-dimensional solids, formulation of constitutive models for advanced materials, as well as development of new approaches to the modeling of damage and fractures.

  1. Advanced Methods for Treatment of Organic Compounds Contamined Water

    OpenAIRE

    PREDESCU Andra; A.Predescu; Ecaterina MATEI

    2009-01-01

    The progress recorded in the field of science and advanced engineering at nanometric scale supplies largeopportunities for more efficient (from the point of view of the costs) and more ecological approach of the processes ofwater purifying. This paper delivers a short description of the possibilities of using advanced materials in purifying thecontamined water with toxic metallic ions, organic and anorganic compounds. The opportunities and challenges werealso emphasized when nanomaterials wer...

  2. Advanced Methods for Treatment of Organic Compounds Contamined Water

    Directory of Open Access Journals (Sweden)

    PREDESCU Andra

    2009-08-01

    Full Text Available The progress recorded in the field of science and advanced engineering at nanometric scale supplies largeopportunities for more efficient (from the point of view of the costs and more ecological approach of the processes ofwater purifying. This paper delivers a short description of the possibilities of using advanced materials in purifying thecontamined water with toxic metallic ions, organic and anorganic compounds. The opportunities and challenges werealso emphasized when nanomaterials were used for the surface, underground and industrial used waters treatment.

  3. Ultrasonic Force Microscopies

    Science.gov (United States)

    Kolosov, Oleg; Briggs, Andrew

    Ultrasonic Force Microscopy, or UFM, allows combination of two apparently mutually exclusive requirements for the nanomechanical probe—high stiffness for the efficient indentation and high mechanical compliance that brings force sensitivity. Somewhat inventively, UFM allows to combine these two virtues in the same cantilever by using indention of the sample at high frequency, when cantilever is very rigid, but detecting the result of this indention at much lower frequency. That is made possible due to the extreme nonlinearity of the nanoscale tip-surface junction force-distance dependence, that acts as "mechanical diode" detecting ultrasound in AFM. After introducing UFM principles, we discuss features of experimental UFM implementation, and the theory of contrast in this mode, progressing to quantitative measurements of contact stiffness. A variety of UFM applications ranging from semiconductor quantum nanostructures, graphene, very large scale integrated circuits, and reinforced ceramics to polymer composites and biological materials is presented via comprehensive imaging gallery accompanied by the guidance for the optimal UFM measurements of these materials. We also address effects of adhesion and topography on the elasticity imaging and the approaches for reducing artifacts connected with these effects. This is complemented by another extremely useful feature of UFM—ultrasound induced superlubricity that allows damage free imaging of materials ranging from stiff solid state devices and graphene to biological materials. Finally, we proceed to the exploration of time-resolved nanoscale phenomena using nonlinear mixing of multiple vibration frequencies in ultrasonic AFM—Heterodyne Force Microscopy, or HFM, that also include mixing of ultrasonic vibration with other periodic physical excitations, eg. electrical, photothermal, etc. Significant section of the chapter analyzes the ability of UFM and HFM to detect subsurface mechanical inhomogeneities, as well as

  4. ADVANCED SEISMIC BASE ISOLATION METHODS FOR MODULAR REACTORS

    Energy Technology Data Exchange (ETDEWEB)

    E. Blanford; E. Keldrauk; M. Laufer; M. Mieler; J. Wei; B. Stojadinovic; P.F. Peterson

    2010-09-20

    Advanced technologies for structural design and construction have the potential for major impact not only on nuclear power plant construction time and cost, but also on the design process and on the safety, security and reliability of next generation of nuclear power plants. In future Generation IV (Gen IV) reactors, structural and seismic design should be much more closely integrated with the design of nuclear and industrial safety systems, physical security systems, and international safeguards systems. Overall reliability will be increased, through the use of replaceable and modular equipment, and through design to facilitate on-line monitoring, in-service inspection, maintenance, replacement, and decommissioning. Economics will also receive high design priority, through integrated engineering efforts to optimize building arrangements to minimize building heights and footprints. Finally, the licensing approach will be transformed by becoming increasingly performance based and technology neutral, using best-estimate simulation methods with uncertainty and margin quantification. In this context, two structural engineering technologies, seismic base isolation and modular steel-plate/concrete composite structural walls, are investigated. These technologies have major potential to (1) enable standardized reactor designs to be deployed across a wider range of sites, (2) reduce the impact of uncertainties related to site-specific seismic conditions, and (3) alleviate reactor equipment qualification requirements. For Gen IV reactors the potential for deliberate crashes of large aircraft must also be considered in design. This report concludes that base-isolated structures should be decoupled from the reactor external event exclusion system. As an example, a scoping analysis is performed for a rectangular, decoupled external event shell designed as a grillage. This report also reviews modular construction technology, particularly steel-plate/concrete construction using

  5. ADVANCED SEISMIC BASE ISOLATION METHODS FOR MODULAR REACTORS

    International Nuclear Information System (INIS)

    Advanced technologies for structural design and construction have the potential for major impact not only on nuclear power plant construction time and cost, but also on the design process and on the safety, security and reliability of next generation of nuclear power plants. In future Generation IV (Gen IV) reactors, structural and seismic design should be much more closely integrated with the design of nuclear and industrial safety systems, physical security systems, and international safeguards systems. Overall reliability will be increased, through the use of replaceable and modular equipment, and through design to facilitate on-line monitoring, in-service inspection, maintenance, replacement, and decommissioning. Economics will also receive high design priority, through integrated engineering efforts to optimize building arrangements to minimize building heights and footprints. Finally, the licensing approach will be transformed by becoming increasingly performance based and technology neutral, using best-estimate simulation methods with uncertainty and margin quantification. In this context, two structural engineering technologies, seismic base isolation and modular steel-plate/concrete composite structural walls, are investigated. These technologies have major potential to (1) enable standardized reactor designs to be deployed across a wider range of sites, (2) reduce the impact of uncertainties related to site-specific seismic conditions, and (3) alleviate reactor equipment qualification requirements. For Gen IV reactors the potential for deliberate crashes of large aircraft must also be considered in design. This report concludes that base-isolated structures should be decoupled from the reactor external event exclusion system. As an example, a scoping analysis is performed for a rectangular, decoupled external event shell designed as a grillage. This report also reviews modular construction technology, particularly steel-plate/concrete construction using

  6. Modeling of ultrasonic propagation in heavy-walled centrifugally cast austenitic stainless steel based on EBSD analysis.

    Science.gov (United States)

    Chen, Yao; Luo, Zhongbing; Zhou, Quan; Zou, Longjiang; Lin, Li

    2015-05-01

    The ultrasonic inspection of heavy-walled centrifugally cast austenitic stainless steel (CCASS) is challenging due to the complex metallurgical structure. Numerical modeling could provide quantitative information on ultrasonic propagation and plays an important role in developing advanced and reliable ultrasonic inspection techniques. But the fundamental obstacle is the accurate description of the complex metallurgical structure. To overcome this difficulty, a crystal orientation map of a CCASS specimen in the 96 mm × 12 mm radial-axial cross section was acquired based on the electron backscattered diffraction (EBSD) technique and it was used to describe the coarse-grained structure and grain orientation. A model of ultrasonic propagation for CCASS was built according to the EBSD map. The ultrasonic responses of the CCASS sample were also tested. Some experimental phenomena such as structural noise and signal distortion were reproduced. The simulated results showed a good consistence with the experiments. The modeling method is expected to be effective for the precise interpretation of ultrasonic propagation in the polycrystalline structures of CCASS. PMID:25670411

  7. Ultrasonic/Sonic Impacting Penetrators

    Science.gov (United States)

    Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Sherrit, Stewart; Stark, Randall A.

    2008-01-01

    are so effective that the axial force needed to make the tool bit advance into the material of interest is much smaller than in ordinary twist drilling, ultrasonic drilling, or ordinary steady pushing.

  8. Effect of ultrasonic treatment of activated carbon on capacitive and pseudocapacitive energy storage in electrochemical supercapacitors

    Directory of Open Access Journals (Sweden)

    B.Ya. Venhryn

    2013-10-01

    Full Text Available Purpose: Use of ultrasonic radiation for improving the properties of activated carbon was the aim of this paper. Increase of density of states at Fermi level was the main factor, responsible for working characteristics of electrochemical supercapacitors. Design/methodology/approach: Working parameters of supercapacitors on the base of activated carbon have been studied by means of precisional porometry, small angle X-ray scattering, cyclic voltamerometry, electrochemical impedance spectroscopy and computer simulation methods. Findings: The possibility to effect the interface between activated carbon and electrolyte by means of ultrasonic treatment in cavitation and noncavitation regimes is proved. It is shown that ultrasonic treatment in noncavitation regimes causes the significant increase of density of states at Fermi level that results in better farad-volt dependences. Research limitations/implications: This research is a complete and accomplished work. Practical implications: Modification of electric double layer by meanans in ultrasonic treatment, proposed in this work, could be regarded as effective way to obtaine the advanced electrode materials in devices of energy generation and storage. Originality/value: This work is important for physics, material science and chemistry because it is related with new possibilities to change the mobility of charge carries in electric double layer by means of ultrasonic irradiation.

  9. Ultrasonic propagation in gases at high temperatures

    Science.gov (United States)

    Carey, C.; Carnevale, E. H.; Lynworth, L. C.; Uva, S.

    1970-01-01

    Ultrasonic pulse method /1 to 3 MHz/ measures both sound speed and absorption in monatomic and polyatomic gases in a temperature range of 300 to 20000 degrees K at atmospheric pressure. Helium, nitrogen, oxygen, and argon are investigated.

  10. Advanced Methods of Observing Surface Plasmon Polaritons and Magnons

    Science.gov (United States)

    Moghaddam, Abolghasem Mobaraki

    Available from UMI in association with The British Library. Requires signed TDF. The primary objectives of this thesis are the investigation of the theoretical and experimental aspects of the design and construction of advanced techniques for the excitation of surface plasmon-polaritons, surface magneto -plasmon-polaritons and surface magnons. They involve on -line observation of these phenomena and to accomplish these goals, analytical studies of the characteristic behaviour of these phenomena have been undertaken. For excitations of surface plasmon- and surface magneto-plasmon-polaritons the most robust and conventional configuration, namely Prism-Medium-Air, coupled to a novel angle scan (prism spinning) method was employed. The system to be described here can automatically measure the reflectivity of a multilayer system over a range of angles that includes the resonance angle in an Attenuated Total Reflection (ATR) experiment. The computer procedure that controls the system is quite versatile so that it allows any right-angle prism of different angle or refractive index to be utilised. It also provided probes to check for optical alignment within the system. Moreover, it performs the angular scan many times and then averages the results in order to reduce the environmental and other possible sources of noise within the system. The mechanical side of the system is unique and could eventually be adopted as a marketable piece of equipment. It consists of a turntable for holding the prism-sample assembly and a drive motor in conjunction with a servo-potentiometer whose output not only operates the turntable but also sends a signal to a computer to measure accurately its position. The interface unit enables a computer to control automatically an angular scan ATR experiment for measuring the resonance reflectivity spectrum of a multilayer system. The interface unit uses an H-bridge switch formed by four bipolar power transistor and two small signal MOSFETs to convert

  11. Bubbles versus biofilms: a novel method for the removal of marine biofilms attached on antifouling coatings using an ultrasonically activated water stream

    Science.gov (United States)

    Salta, M.; Goodes, L. R.; Maas, B. J.; Dennington, S. P.; Secker, T. J.; Leighton, T. G.

    2016-09-01

    The accumulation of marine organisms on a range of manmade surfaces, termed biofouling, has proven to be the Achilles’ heel of the shipping industry. Current antifouling coatings, such as foul release coatings (FRCs), only partially inhibit biofouling, since biofilms remain a major issue. Mechanical ship hull cleaning is commonly employed to remove biofilms, but these methods tend to damage the antifouling coating and often do not result in full removal. Here, we report the effectiveness of biofilm removal from FRCs through a novel cleaning device that uses an ultrasonically activated stream (UAS). In this device, ultrasound enhances the cleaning properties of microbubbles in a freely flowing stream of water. The UAS was applied on two types of commercial FRCs which were covered with biofilm growth following twelve days immersion in the marine environment. Biofilm removal was quantified in terms of reduction in biovolume and surface roughness, both measured using an optical profilometer, which were then compared with similar measurements after cleaning with a non-ultrasonically activated water stream. It was found that the UAS significantly improves the cleaning capabilities of a water flow, up to the point where no detectable biofilm remained on the coating surfaces. Overall biofilm surface coverage was significantly lower on the FRC coatings cleaned with the UAS system when compared to the coatings cleaned with water or not cleaned at all. When biofilm biomass removal was investigated, the UAS system resulted in significantly lower biovolume values even when compared to the water cleaning treatment with biovolume values close to zero. Remarkably, the surface roughness of the coatings after cleaning with the UAS was found to be comparable to that of the blank, non-immersed coatings, illustrating that the UAS did not damage the coatings in the process. The data supporting this study are openly available from the University of Southampton repository at http

  12. Ultrasonic Evaluation of the Impact Damage of Polymer Bonded Explosives

    Institute of Scientific and Technical Information of China (English)

    陈鹏万; 戴开达; 黄风雷; 丁雁生

    2004-01-01

    The damage properties of polymer bonded explosives under dynamic loading were studied by using ultrasonic evaluation. Explosive samples were damaged by a low-velocity gas gun at different impact velocities. Ultrasonic examination was carried out with a pulse through-transmission method. Spectra analyses were carried out by using fast Fourier transform. Characteristic ultrasonic parameters, including ultrasonic velocities, attenuation coefficients, spectra area and master frequency, were obtained. The correlation between the impact damage and ultrasonic parameters was analyzed. A damage coefficient D was defined by considering a combination of ultrasonic velocity and amplitude. The results show that ultrasonic parameters can be used to quantitatively assess the damage extent in impacted plastic bonded explosives.

  13. Ultrasonic Flowmeter for JSFR

    International Nuclear Information System (INIS)

    The piping materials of the Japan Sodium-Cooled Fast Reactor (JSFR) at the commercialized stage, will be ferromagnetic materials Mod. 9-Cr steel. Therefore, it is not feasible to adopt the electromagnetic flowmeters used in conventional FBR plants. This paper describes the developmental status of the ultrasonic flowmeter system (USFM) as a substitute flow rate measurement system for JSFR. The features of the USFM are the following; - In consideration of the double wall piping structure of JSFR, ultrasonic transducers should be installed directly on the surface of the inner primary coolant piping. Therefore, the transducers should work properly under 395 oC at the rated power, and be replaced by a remote replacement system. - The transducer remote replacement system should maintain the air tightness between the inner primary coolant piping and the outer piping during the normal plant operation, apply appropriate pressure to the transducers against the inner primary coolant piping, and replace the transducers without removing the outer piping under the maitenance outage. - The multi-pass propagation time method is effective for detection of the flow rate in the short entrance region (in the short straight piping). The requirements of the signal processor are the following; Linearity and repeatability of the output signal : ± 2% or less of full scale; Fluctuation rate of the output signal : ± 5% or less of the median; Response : 0.3 s or less. - The USFM is designed as one of the safety protection system. (author)

  14. Ultrasonic flowmeter for JSFR

    International Nuclear Information System (INIS)

    The piping materials of the Japan Sodium-Cooled Fast Reactor (JSFR) at the commercialized stage, will be ferromagnetic materials Mod. 9-Cr steel.Therefore, it is not feasible to adopt the electromagnetic flowmeters used in conventional FBR plants. This paper describes the developmental status of the ultrasonic flowmeter system (USFM) as a substitute flow rate measurement system to JSFR. The features of the USFM are the following; In consideration of the double wall piping structure on JSFR, ultrasonic transducers should be installed directly on the surface of the inner primary coolant pipe. Therefore, the transducers should work properly under the temperature of 395 degrees Cat the rated power, and be replaced by remote replacement system; The transducer remote exchange system should maintain with air tightness between the inner primary coolant piping and the outer piping during the normal plant operation, apply appropriate pressure to the transducers against the inner primary coolant piping, and exchange the transducers without removing the outer piping under the maintenance outage; Multi-pass propagation time method is effective for detection of flow rate in the short entrance region (e.g. in the short straight piping) and the requirements of the signal processing equipment are the following; Linearity and repeatability of output signal : less than± 2% of Full Scale; Fluctuation rate of output signal : less than ± 5% of median; Response : less than 0.3 s; The USFM is designed as one of the Safety Protection System

  15. 超声波流量计的低功耗高精度时间测量方法%Low Power and High Precision Time Measurement Method of Ultrasonic Flow Meter

    Institute of Scientific and Technical Information of China (English)

    刘秀红; 田志宏; 果红军

    2009-01-01

    Measure of time is a key technique of ultrasonic flow meter. A low power and high precision time-measurement method was analyzed. Work theory of time difference ultrasonic flow meter was described. Low power and high precision design method of ultrasonic flow meter was presented. It achieved the designing project that made use of technique of super low power Msp430 MCU and 'zero power' high speed CPLD. The ultrasonic flow meter has some characteristic,such as high measurement precision,big pipe diameter width,untouching flow,jam mingless,using convenience.%时间测量是超声波流量计的关键技术,分析了一种低功耗高精度的时间测量方法.介绍了时差法超声波流量计工作原理和超声波流量计低功耗高精度的设计方法,采用超低功耗的MSP430单片机及"零功耗"高速CPLD技术实现了设计方案.该方法设计的超声波流量计具有计量精度高、管径范围宽、不接触流体、不易堵塞、使用方便等特点,测时精度可以达到2.5 ns以上.

  16. Flexible Ultrasonic Phased-Array Probe

    Institute of Scientific and Technical Information of China (English)

    施克仁; 阙开良; 郭大勇

    2004-01-01

    In ultrasonic phased-array testing, most probes are rigid with fixed elements. However, when testing a cambered piece, a rigid probe cannot be used directly, but an ultrasonic chock or coupling media must be used, which adds cost and reduces the accuracy. The objective of this research was to improve the tests of cambered pieces. A flexible ultrasonic phased-array probe was developed to do the flexible phased-array testing. The key technologies in the flexible phased-array probe include the probe design and the phased-array control. A new method was developed to design the flexible probe according to the curvature of the piece and the test depth. The method includes the calculation of the element's height (he), the relative rotation angle ((e), the distance between the adjoining elements (de), and the element's effective testing range. A flexible ultrasonic phased-array probe has been developed using this method.

  17. Nonlinear Ultrasonic Measurements in Nuclear Reactor Environments

    Science.gov (United States)

    Reinhardt, Brian T.

    Several Department of Energy Office of Nuclear Energy (DOE-NE) programs, such as the Fuel Cycle Research and Development (FCRD), Advanced Reactor Concepts (ARC), Light Water Reactor Sustainability, and Next Generation Nuclear Power Plants (NGNP), are investigating new fuels, materials, and inspection paradigms for advanced and existing reactors. A key objective of such programs is to understand the performance of these fuels and materials during irradiation. In DOE-NE's FCRD program, ultrasonic based technology was identified as a key approach that should be pursued to obtain the high-fidelity, high-accuracy data required to characterize the behavior and performance of new candidate fuels and structural materials during irradiation testing. The radiation, high temperatures, and pressure can limit the available tools and characterization methods. In this thesis, two ultrasonic characterization techniques will be explored. The first, finite amplitude wave propagation has been demonstrated to be sensitive to microstructural material property changes. It is a strong candidate to determine fuel evolution; however, it has not been demonstrated for in-situ reactor applications. In this thesis, finite amplitude wave propagation will be used to measure the microstructural evolution in Al-6061. This is the first demonstration of finite amplitude wave propagation at temperatures in excess of 200 °C and during an irradiation test. Second, a method based on contact nonlinear acoustic theory will be developed to identify compressed cracks. Compressed cracks are typically transparent to ultrasonic wave propagation; however, by measuring harmonic content developed during finite amplitude wave propagation, it is shown that even compressed cracks can be characterized. Lastly, piezoelectric transducers capable of making these measurements are developed. Specifically, three piezoelectric sensors (Bismuth Titanate, Aluminum Nitride, and Zinc Oxide) are tested in the Massachusetts

  18. A Method for Increasing Elders' Use of Advance Directives.

    Science.gov (United States)

    Luptak, Marilyn K.; Boult, Chad

    1994-01-01

    Studied effectiveness of intervention to help frail elders to record advance directives (ADs). In collaboration with physicians and lay volunteer, social worker provided information/counseling to elderly subjects, families, and proxies in series of visits to geriatric evaluation and management clinic. Seventy-one percent of subjects recorded ADs.…

  19. Design of advanced industrial furnaces using numerical modeling method

    OpenAIRE

    Dong, Wei

    2000-01-01

    This doctoral thesis describes the fundamentals ofmathematical modeling for the industrial furnaces and boilersand presents the results from the numerical simulations of sometypical applications in advanced industrial furnaces andboilers. The main objective of this thesis work is to employcomputational fluid dynamics (CFD) technology as an effectivecomputer simulation tool to study and develop the newcombustion concepts, phenomena and processes in advancedindustrial furnaces and boilers. The ...

  20. Advancing multilevel thinking and methods in HRM research

    NARCIS (Netherlands)

    Renkema, Maarten; Meijerink, Jeroen; Bondarouk, Tanya

    2016-01-01

    Purpose Despite the growing belief that multilevel research is necessary to advance HRM understanding, there remains a lack of multilevel thinking – the application of principles for multilevel theory building. The purpose of this paper is to propose a systematic approach for multilevel HRM research

  1. Testresults KROHNE 8-inch ultrasonic flowmeter

    Energy Technology Data Exchange (ETDEWEB)

    Boer, A.H.; Volmer, W.

    1997-07-01

    A new development in the field of ultrasonic liquid flowmeasurements has been achieved with the multichannel liquid ultrasonic flowmeter; the first for use in maintenance-free custody transfer applications. Although ultrasonic flowmeters are used for applications in the oil industry for many years, this new development will have a big impact on custody transfer flow measurement. Not only because of the compactness, but also because of the low investment and operating cost of this flowmeter. This paper describes the system and the method of operation as well as practical experiences and achieved test results of this flowmeter. (author)

  2. Methodical aspects of ultrasonic research of cervical intervertebral disk and spiral canal children of the advanced school age

    International Nuclear Information System (INIS)

    Held ultrasound intervertebral discs (MPD), the spinal canal (PC) with the level of C2-C3 to C7-TH1 67 healthy children in the age groups 13-15 and 16-18 years. In the sagittal and axial projections defined sizes MPD PC dural spaces, radicular channels. Studied echo structure nucleus pulposus, the contours of the fibrous ring

  3. Determination of plant components degradation using ultrasonic C-scan

    International Nuclear Information System (INIS)

    C-scan Ultrasonic Inspection technique is increasingly used for the assessment of plant integrity. Due to the advancement of the equipment, Probability of Detection (POD) of this technique increased significantly as compared with the conventional techniques. Thus in many cases, the technique is accepted by engineers to be used to replace the conventional inspection methods such as visual inspections, thickness gauging and ultrasonic B-Scan. Thickness gauging and ultrasonic B-scan is still widely used by industries. However, both techniques have their own disadvantages. The most notable disadvantages of these techniques are related to the reliability of readings given by the equipment. In addition to this, thickness gauge would only provide data at certain points and B-scan would only provide data for certain lines. This paper presents and discusses results of C-scan measurement performed in power generation, chemical and petro-chemical plants. Due to its high accuracy, results from these measurements were used to establish the true condition of plant and to calculate its remaining safe life. Results presented in this paper include those related to corrosion, erosion and lamination in acid and gas pipelines, finger sludge catcher, steam drums in vessels and piping and electron beam machine. (Author)

  4. Conceptual frameworks and methods for advancing invasion ecology.

    Science.gov (United States)

    Heger, Tina; Pahl, Anna T; Botta-Dukát, Zoltan; Gherardi, Francesca; Hoppe, Christina; Hoste, Ivan; Jax, Kurt; Lindström, Leena; Boets, Pieter; Haider, Sylvia; Kollmann, Johannes; Wittmann, Meike J; Jeschke, Jonathan M

    2013-09-01

    Invasion ecology has much advanced since its early beginnings. Nevertheless, explanation, prediction, and management of biological invasions remain difficult. We argue that progress in invasion research can be accelerated by, first, pointing out difficulties this field is currently facing and, second, looking for measures to overcome them. We see basic and applied research in invasion ecology confronted with difficulties arising from (A) societal issues, e.g., disparate perceptions of invasive species; (B) the peculiarity of the invasion process, e.g., its complexity and context dependency; and (C) the scientific methodology, e.g., imprecise hypotheses. To overcome these difficulties, we propose three key measures: (1) a checklist for definitions to encourage explicit definitions; (2) implementation of a hierarchy of hypotheses (HoH), where general hypotheses branch into specific and precisely testable hypotheses; and (3) platforms for improved communication. These measures may significantly increase conceptual clarity and enhance communication, thus advancing invasion ecology.

  5. Ultrasonic testing device

    International Nuclear Information System (INIS)

    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)

  6. The driving methods of the autonomous navigated ultrasonic exploring car%超声探路车的自主导航行驶办法

    Institute of Scientific and Technical Information of China (English)

    张海鹰; 高艳丽; 张树团

    2011-01-01

    In order to increase the autonomous navigated capability of the intelligent car in absolute unknown environment,a method that using an ultrasonic sensor driven by a step motor for rotating detection is designed. It could get more exact and comprehensive environment information than the old ways. Base on this, several kinds of traveling methods including the tracking drive method are designed against different conditions. And also the setting values of the parameters and the relations between parameters in the system are analyzed. It makes the car can drive with high efficiency in ali environments.%为了加强智能车辆在全未知环境下的自主导航行驶能力,设计了使用步进电动机驱动小波束角超声传感器旋转探测的方法,获取了较以往相比更加全面准确地环境信息.在此基础上,针对不同的环境状况设计了包含循线行驶模式在内的多种行驶方法,并分析了在各种不同的行驶模式下系统相关参数的设置,和各参数之间的关系,使车辆在各类环境下都能保持较高的行驶效率.

  7. Ultrasonic Verification of Composite Structures

    OpenAIRE

    Pelt, Maurice; Boer, Robert Jan,; Schoemaker, Christiaan; Sprik, Rudolf

    2014-01-01

    International audience Ultrasonic Verification is a new method for the monitoring large surface areas of CFRP by ultrasound with few sensors. The echo response of a transmitted pulse through the structure is compared with the response of an earlier obtained reference signal to calculate a fidelity parameter. A change in fidelity over time is indicative for a new defect in the structure. This paper presents an experimental assessment of the effectiveness and reproducibility of the method.

  8. The Study of T-beam Thickness Detection Method Based on Ultrasonic Velocity Measurement%基于超声波法的T梁厚度检测方法研究

    Institute of Scientific and Technical Information of China (English)

    谢盛明; 汪继文; 詹小丽; 姜维; 邵华

    2015-01-01

    In order to do an express test for bridge slab thickness, a research was carried out on detection method of thickness of typical T-beam on bridge by ultrasonic.The detection precision of this detection method was also analyzed in this paper.The results indicate that the maximum measurement error of T-beam diaphragm by ul-trasonic is 3.5%and the maximum measurement error of T-beam web is 16.4%.According to the test results by ultrasonic velocity measurement, this paper focuses on the problem of ultrasonic measurement on bridge slab thick-ness and proposes accuracy correction of ultrasonic velocity measurement on bridge slab thickness.Research results show that ultrasonic velocity measurement on bridge slab thickness has superiority while still existing drawbacks. The difficult and key points of bridge slab thickness test by ultrasonic are how to select positions quickly and im-prove the precision of data processing.%为快速测试桥梁梁板厚度,本研究运用超声波法对典型桥梁T梁梁板厚度检测方法进行研究,并对其检测方法的检测精度进行分析。研究发现超声波测量T梁横隔板边缘测量误差最大为3.5%,T梁中腹板超声波测量误差最大为20%。根据超声波法的测试结果,提出了超声波测试桥梁梁板精度修正的处理方法。研究结果表明超声波在桥梁梁板厚度测试中具有优越性的同时也存在一些问题,如何克服超声波梁板厚度测试快速定点及测试结果数据处理提高精度是超声波梁板厚度测试的难点和关键。

  9. 78 FR 16513 - Application of Advances in Nucleic Acid and Protein Based Detection Methods to Multiplex...

    Science.gov (United States)

    2013-03-15

    ... Advances in Nucleic Acid and Protein Based Detection Methods to Multiplex Detection of Transfusion... protein based pathogen and blood cell antigen detection methods and to discuss the scientific pathways to... HUMAN SERVICES Food and Drug Administration Application of Advances in Nucleic Acid and Protein...

  10. Experiences from introduction of peer-to-peer teaching methods in Advanced Biochemistry E2010

    DEFF Research Database (Denmark)

    Brodersen, Ditlev; Etzerodt, Michael; Rasmussen, Jan Trige

    2012-01-01

    During the autumn semester 2010, we experimented with a range of active teaching methods on the course, Advanced Biochemistry, at the Department of Molecular Biology and Genetics.......During the autumn semester 2010, we experimented with a range of active teaching methods on the course, Advanced Biochemistry, at the Department of Molecular Biology and Genetics....

  11. Ultrasonic Waves and Strength Reduction Indexes for the Assessment of the Advancement of Deterioration Processes in Travertines from Pamukkale and Hierapolis (Turkey)

    Science.gov (United States)

    Bobrowska, Alicja; Domonik, Andrzej

    2015-09-01

    In constructions, the usefulness of modern technical diagnostics of stone as a raw material requires predicting the effects of long-term environmental impact of its qualities and geomechanical properties. The paper presents geomechanical research enabling presentation of the factors for strength loss of the stone and forecasting the rate of development of destructive phenomena on the stone structure on a long-time basis. As research material Turkish travertines were selected from the Denizli-Kaklık Basin (Pamukkale and Hierapolis quarries), which have been commonly used for centuries in global architecture. The rock material was subjected to testing of the impact of various environmental factors, as well as European standards recommended by the author of the research program. Their resistance to the crystallization of salts from aqueous solutions and the effects of SO2, as well as the effect of frost and high temperatures are presented. The studies allowed establishing the following quantitative indicators: the ultrasonic waves index (IVp) and the strength reduction index (IRc). Reflections on the assessment of deterioration effects indicate that the most active factors decreasing travertine resistance in the aging process include frost and sulphur dioxide (SO2). Their negative influence is particularly intense when the stone material is already strongly weathered.

  12. Ultrasonic Sensing and Life Prediction for the DARPA Structural Integrity Prognosis System

    Science.gov (United States)

    Michaels, Jennifer E.; Michaels, Thomas E.; Cobb, Adam C.; Kacprzynski, Gregory J.

    2007-03-01

    The overall objective of the DARPA Structural Integrity Prognosis System (SIPS) program is to develop technologies to advance material damage state condition assessment with limited or no dedicated maintenance action. As a part of the sensors thrust area, an in situ ultrasonic sensing method was developed and demonstrated to detect cracks initiating from fastener holes and provide an estimate of total crack area. Crack area estimates were combined with load history data, projected future loads, and life prediction models to determine a probability density function for time-to-failure. The ultrasonic method utilizes two shear wave angle beam transducers operating in through transmission mode which are mounted on either side of the hole. The transmitted wave travels through the area of expected cracking, and the presence of cracks around the fastener holes decreases the amount of acoustic energy that is received. Furthermore, as cracks open and close during the fatigue process, the received energy is modulated, i.e., decreased when the cracks are open versus closed, and this non-linear behavior is the basis of algorithms developed to detect and size fastener holes cracks. The ultrasonic method was demonstrated as part of an integrated SIPS demonstration whereby aircraft-grade aluminum subcomponents were fatigued to failure. Results are presented from both the ultrasonic measurements and the integrated life prediction software.

  13. Experimental method of measuring sound velocity using ultrasonic flowmeter%超声波流量计测量流体声速的实验方法

    Institute of Scientific and Technical Information of China (English)

    王新峰; 熊显潮; 高敏忠

    2011-01-01

    为获取液体介质的声速值,设计了一种测定流体声速的实验方法,该方法利用时差式超声波流量计和标准流量校验设备同时对封闭管道中的液体进行流速测量,分别得到流速的测量值和真实值,从而计算出超声波流量计的仪表系数,并以此导出了一定条件下液体介质的声速值随仪表系数的变化关系式.利用该方法测量给出了0.17MPa下四氧化二氮(N2O4)在7.6—19.4℃、偏二甲肼((CH3)2NNH2)在6.5—25.2℃范围内的流体声速值,并为其他液体介质的声速测量提供了借鉴.%In order to obtain sound velocity in liquid,an experimental method of measuring sound velocity is designed.A time-difference type ultrasonic flowmeter and normal flow checkout equipment are used to measure the flow speed of liquid in closed hydraulic pipeline simultaneously,then the measured value and the true value of the flow rate are measured,and the meter-factor of the ultrasonic flowmeter is determined.Furthermore,the relationship between the sound velocity and the meter-factor is derived under a certain condition.Based on the method,the velocity of sound in dinitrogen tetroxide (N2O4) at 7.6—19.4℃ and unsymmetric dimethyl hydrazine ((CH3)2NNH2) at 6.5—25.2℃ are measured at 0.17MPa.It provides reference for measuring the sound velocity in other liquid.

  14. Advanced 3D inverse method for designing turbomachine blades

    Energy Technology Data Exchange (ETDEWEB)

    Dang, T. [Syracuse Univ., NY (United States)

    1995-10-01

    To meet the goal of 60% plant-cycle efficiency or better set in the ATS Program for baseload utility scale power generation, several critical technologies need to be developed. One such need is the improvement of component efficiencies. This work addresses the issue of improving the performance of turbo-machine components in gas turbines through the development of an advanced three-dimensional and viscous blade design system. This technology is needed to replace some elements in current design systems that are based on outdated technology.

  15. Nonlinear dynamics of rotating shallow water methods and advances

    CERN Document Server

    Zeitlin, Vladimir

    2007-01-01

    The rotating shallow water (RSW) model is of wide use as a conceptual tool in geophysical fluid dynamics (GFD), because, in spite of its simplicity, it contains all essential ingredients of atmosphere and ocean dynamics at the synoptic scale, especially in its two- (or multi-) layer version. The book describes recent advances in understanding (in the framework of RSW and related models) of some fundamental GFD problems, such as existence of the slow manifold, dynamical splitting of fast (inertia-gravity waves) and slow (vortices, Rossby waves) motions, nonlinear geostrophic adjustment and wa

  16. The Riemann Conjecture and the advanced Calculus Methods for Physics

    OpenAIRE

    Botelho, Luiz. C. L.

    2009-01-01

    We present a set of lectures on topics of advanced calculus in one real and complex variable with several new results and proofs on the subject, specially with detailed proof-always missing in the literature - of the Cissoti explicitly integral formula conformally representing a polygon onto a disc.Besides we present-in the paper appendix-a new study embodied with a mathematical physicist perspective,on the famous Riemann conjecture on the zeros of the Zeta function, reducing its proof to a c...

  17. Design of travel time difference method ultrasonic flowmeter based on FPGA%基于FPGA的时差法超声波流量计的设计

    Institute of Scientific and Technical Information of China (English)

    肖海; 王亚非; 高椿明

    2009-01-01

    设计了一种基于现场可编程门阵列(FPGA)的时差法超声波流量计.主要介绍了系统的硬件组成和实现方法,概述了软件功能和软件设计流程.系统硬件电路为微控制器+FPGA结构,微控制器是系统的控制核心.利用FPGA的可编程特性和很高的工作频率以及丰富的内部资源设计了包括高速计数器在内的数字信号处理模块,提高了系统的可靠性和测量精度,并具有良好的硬件可升级性.%A travel time difference method ultrasonic flowmeter based on field programmable gate array (FPGA) is designed. The hardware structure and realization method are introduced. The software function and work mode are overviewed. The hardware structure of the system is microcontroller +FPGA. The microcontroller is the control center. Making use of the programmable characteristic, the rich inner resources and very high work frequency of a FPGA chip,a date signal processes module including a high speed counter is designed. The reliability and the measurement precision of system are improved. And the hardware can be upgraded more easily.

  18. Application of TDC-GP21 in ultrasonic flowmeter based on time difference method%TDC-GP21在时差法超声波流量计中的应用

    Institute of Scientific and Technical Information of China (English)

    邵慧

    2012-01-01

    为了使超声波流量计的精度范围能达到±0.5%,研究了时差法超声波的测量原理,分析了实现高精度测量的设计方法.介绍了系统的工作过程和硬件组成,详细阐述了测时芯片高速时间数字转换器TDC-GP21 (Time-to-Digital-Converter)的结构和功能原理,以及其在超声波流量计时间测量模块中系统硬件部分的实现.采用TDC-GP21,ARM微处理器、超声波收发电路等硬件架构,实现了高精度测量超声波顺流和逆流传播时间差.实验结果和精度分析表明,研制的超声波流量计符合设计要求,并为超声波流量计的高精度和低功耗设计提供了一个参考.%In order to make the accuracy of ultrasonic flowmeter reach ,the measurement principle of time-difference ultrasonic is studied, and the method to achieve high-precision measurements is analyzed. The system work process and hardware composition is introduced . The structure and principle of high-speed interval measuring chip TDC-GP21 as well as the hardware realization of ultrasonic measurement system is mainly elaborated. The high-precision measurement of ultrasonic downstream and upstream propagation time difference was achieved by using TDC-GP21 , ARM microprocessor, ultrasonic transceiver circuit and other hardware architecture. The experiment result and accuracy analysis confirms that the ultrasonic flowmeter developed in this way can meet the design requirements. It provides a reference for high-accuracy and low-power design of ultrasonic flowmeter.

  19. Method of advancing research and development of fast breeder reactors

    International Nuclear Information System (INIS)

    In the long term plan of atomic energy development and utilization, FBRs are to be developed as the main of future nuclear power generation in Japan, and when the development is advanced, it is positivity aimed at building up the plutonium utilization system using FBRs superior to the uranium utilization system with LWRs. Also it was decided that it is necessary to exert incessant effort for the development of FBRs under the proper cooperation system of the government and people for a considerable long period, and as for the concrete development, hereafter, the deliberation is advanced by the expert subcommittee on FBR development project of the Atomic Energy Commission in succession. The subcommittee was founded in May, 1986, to carry out the deliberation on the long term promotion measures for the development of FBRs, the promotion measures for the research and development, the evaluation and examination of the basic specification of a demonstration FBR, the promotion measures for the international cooperation and other important matters related to the development of FBRs. The construction of the prototype FBR 'Monju' is in progress aiming at the criticality in 1992, and the start of construction of a demonstration FBR is expected in the latter half of 1990s. The situation around the development of FBRs, the fundamentals for promoting the research and development, and the subjects of the research and development are reported. (Kako, I.)

  20. Ultrasonic and eddy current testing of austenitic platings of reactor pressure vessels - qualification according the ENIQ method; Ultraschall- und Wirbelstrompruefung austenitischer Plattierungen von Reaktorbehaeltern - Qualifizierung nach der Methode von ENIQ

    Energy Technology Data Exchange (ETDEWEB)

    Just, T.; Csapo, G. [TUeV NORD SysTec GmbH and Co. KG, Hamburg (Germany); Brenner, W. [TUeV Sueddeutschland-ET, Mannheim (Germany); Waidele, H. [MPA, Univ. Stuttgart (Germany)

    2004-07-01

    In the context of the research project SR2318, which received funds from the Federal Radiation Protection Office (Bundesamt fuer Strahlenschutz) and the BMU, the accuracy of eddy current and ultrasonic tests of austenitic platings on reactor pressure vessels was investigated. The results were evaluated with a view to qualification of combined ultrasonic and eddy current tests of platings and base materials on the one hand; on the other hand, a standard test procedure according to the ENIQ method (European Network of Inspection Qualification) is proposed which can serve as a basis for qualification of test procedures. Summarizing suggestions are made for updating the KTA 3201.4 regulation for recurrent inspections of platings. The results of research project SR 2351 are considered. (orig.) [German] Im Rahmen des vom Bundesamt fuer Strahlenschutz bzw. des BMU gefoerderten Untersuchungsvorhabens SR2318 wurde die Aussagefaehigkeit von Ultraschall- und Wirbelstrompruefungen an austenitischen Plattierungen von Reaktordruckbehaeltern untersucht. Die im Untersuchungsvorhaben erzielten Ergebnisse werden zum einen hinsichtlich der Qualifizierung der Pruefung von Plattierungen und des daran angrenzenden Grundwerkstoffes mittels mechanisierter Ultraschallpruefung in Kombination mit der Wirbelstrompruefung bewertet, und es wird zum anderen beispielhaft ein Muster fuer eine Qualifizierung nach der Methodik von ENIQ (European Network of Inspection Qualification) vorgeschlagen, nach dem kuenftig bei Qualifikationen von Pruefverfahren vorgegangen werden kann. Als Quintessenz werden daraus Vorschlaege zur Ergaenzung der Regel KTA 3201.4 hinsichtlich der wiederkehrenden Pruefungen (WKP) von Plattierungsbereichen formuliert. Dabei sind die Ergebnisse des Untersuchungsvorhabens SR 2351 einbezogen worden. (orig.)

  1. Introduction to Rheology for Ultrasonic Engineers

    Science.gov (United States)

    Ueda, Takanobu

    2008-05-01

    Here, I introduce the fundamental concept and methodology of rheology measurement especially to researchers in the field of ultrasonic engineering. Althogh we consider the material as fluid and characterize it in terms of viscosity accompanied by its complex part representing elasticity, ultrasonic spectroscopy regards the material as solid with elasticity, which determines ultrasonic velocity. Although these two research fields have contrary viewpoints, they share the purpose of the study, that is, to characterize the mechanical properties of the material as a function of frequency or shear rate and to reveal its mechanism and structure at the molecular level. In this paper, I show the basic methods of rheology measurement and analysis in relation to ultrasonic technology.

  2. Advanced methods of microscope control using μManager software

    Directory of Open Access Journals (Sweden)

    Arthur D Edelstein

    2014-07-01

    Full Text Available µManager is an open-source, cross-platform desktop application, to control a wide variety of motorized microscopes, scientific cameras, stages, illuminators, and other microscope accessories. Since its inception in 2005, µManager has grown to support a wide range of microscopy hardware and is now used by thousands of researchers around the world. The application provides a mature graphical user interface and offers open programming interfaces to facilitate plugins and scripts. Here, we present a guide to using some of the recently added advanced µManager features, including hardware synchronization, simultaneous use of multiple cameras, projection of patterned light onto a specimen, live slide mapping, imaging with multi-well plates, particle localization and tracking, and high-speed imaging.

  3. Advances In Burnup Credit Criticality Safety Analysis Methods And Applications

    International Nuclear Information System (INIS)

    An International Workshop on “Advances in Applications of Burnup Credit for Spent Fuel Storage, Transport, Reprocessing, and Disposition” organized by the Nuclear Safety Council of Spain (CSN) in cooperation with the International Atomic Energy Agency (IAEA) was held at Córdoba, Spain, on October 27– 30, 2009. The objectives of this workshop were to identify the benefits that accrue from recent improvements of the burnup credit (BUC) analysis methodologies, to analyze the implications of applying improved BUC methodologies, focusing on both the safety-related and operational aspects, and to foster the exchange of international experience in licensing and implementation of BUC applications. In the paper on hand the attention is focused on the improvements of BUC analysis methodologies. (author)

  4. Recent advances in neutral particle transport methods and codes

    Energy Technology Data Exchange (ETDEWEB)

    Azmy, Y.Y.

    1996-06-01

    An overview of ORNL`s three-dimensional neutral particle transport code, TORT, is presented. Special features of the code that make it invaluable for large applications are summarized for the prospective user. Advanced capabilities currently under development and installation in the production release of TORT are discussed; they include: multitasking on Cray platforms running the UNICOS operating system; Adjacent cell Preconditioning acceleration scheme; and graphics codes for displaying computed quantities such as the flux. Further developments for TORT and its companion codes to enhance its present capabilities, as well as expand its range of applications are disucssed. Speculation on the next generation of neutron particle transport codes at ORNL, especially regarding unstructured grids and high order spatial approximations, are also mentioned.

  5. Advances in microfluidics-based experimental methods for neuroscience research.

    Science.gov (United States)

    Park, Jae Woo; Kim, Hyung Joon; Kang, Myeong Woo; Jeon, Noo Li

    2013-02-21

    The application of microfluidics to neuroscience applications has always appealed to neuroscientists because of the capability to control the cellular microenvironment in both a spatial and temporal manner. Recently, there has been rapid development of biological micro-electro-mechanical systems (BioMEMS) for both fundamental and applied neuroscience research. In this review, we will discuss the applications of BioMEMS to various topics in the field of neuroscience. The purpose of this review is to summarise recent advances in the components and design of the BioMEMS devices, in vitro disease models, electrophysiology and neural stem cell research. We envision that microfluidics will play a key role in future neuroscience research, both fundamental and applied research.

  6. Comparison of Advanced Distillation Control Methods, Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Dr. James B. Riggs

    2000-11-30

    Detailed dynamic simulations of three industrial distillation columns (a propylene/propane splitter, a xylene/toluene column, and a depropanizer) have been used to evaluate configuration selections for single-ended and dual-composition control, as well as to compare conventional and advanced control approaches. In addition, a simulator of a main fractionator was used to compare the control performance of conventional and advanced control. For each case considered, the controllers were tuned by using setpoint changes and tested using feed composition upsets. Proportional Integral (PI) control performance was used to evaluate the configuration selection problem. For single ended control, the energy balance configuration was found to yield the best performance. For dual composition control, nine configurations were considered. It was determined that the use of dynamic simulations is required in order to identify the optimum configuration from among the nine possible choices. The optimum configurations were used to evaluate the relative control performance of conventional PI controllers, MPC (Model Predictive Control), PMBC (Process Model-Based Control), and ANN (Artificial Neural Networks) control. It was determined that MPC works best when one product is much more important than the other, while PI was superior when both products were equally important. PMBC and ANN were not found to offer significant advantages over PI and MPC. MPC was found to outperform conventional PI control for the main fractionator. MPC was applied to three industrial columns: one at Phillips Petroleum and two at Union Carbide. In each case, MPC was found to significantly outperform PI controls. The major advantage of the MPC controller is its ability to effectively handle a complex set of constraints and control objectives.

  7. Viscous-Inviscid Coupling Methods for Advanced Marine Propeller Applications

    OpenAIRE

    Martin Greve; Katja Wöckner-Kluwe; Moustafa Abdel-Maksoud; Thomas Rung

    2012-01-01

    The paper reports the development of coupling strategies between an inviscid direct panel method and a viscous RANS method and their application to complex propeller ows. The work is motivated by the prohibitive computational cost associated to unsteady viscous flow simulations using geometrically resolved propellers to analyse the dynamics of ships in seaways. The present effort aims to combine the advantages of the two baseline methods in order to reduce the numerical effort without comprom...

  8. A Novel Approach to Correct Diffraction Effect in Measurement of Ultrasonic Velocity and Attenuation at High Frequencies

    Institute of Scientific and Technical Information of China (English)

    ZHANG Dong(章东); LIU Xiao-Zhou(刘晓宙); GONG Xiu-Fen(龚秀芬); KUSHIBIKI Jun-Ichi

    2003-01-01

    A novel method to correct diffraction effect in measurement of ultrasonic velocity and attenuation at high frequencies is developed by using the superposition technique of Gaussian beams. To examine the validity of this numerical approach, the amplitude loss and phase advance due to the diffraction effect for an SiO2 specimen are numerically calculated in 30-240MHz, and the results are in good agreement with those by the Papadakis method.

  9. Computer Simulation of Multiple Reflection Waves for Thickness Measurement by Ultrasonic Spectroscopy

    International Nuclear Information System (INIS)

    Ultrasonic spectroscopy is likely to become a very powerful NDE method for detection of microfects and thickness measurement of thin film below the limit of ultrasonic distance resolution in the opaque materials, provides a useful information that cannot be obtained by a conventional ultrasonic measuring system. In this paper, we considered a thin film below the limit of ultrasonic distance resolution sandwitched between two substances as acoustical analysis model, demonstrated the usefulness of ultrasonic spectroscopic analysis technique using information of ultrasonic frequency for measurements of thin film thickness, regardless of interference phenomenon and phase reversion of ultrasonic waveform. By using frequency intervals(Δf) of periodic minima from the ratio of reference power spectrum of reflective waveform obtained a sample to power spectrum of multiple reflective waves obtained interference phenomenon caused by ultrasonic waves reflected at the upper and lower surfaces of a thin layer, can measured even dimensions of interest are smaller than the ultrasonic wave length with simplicity and accuracy

  10. Advanced Welding Concepts

    Science.gov (United States)

    Ding, Robert J.

    2010-01-01

    Four advanced welding techniques and their use in NASA are briefly reviewed in this poster presentation. The welding techniques reviewed are: Solid State Welding, Friction Stir Welding (FSW), Thermal Stir Welding (TSW) and Ultrasonic Stir Welding.

  11. Ultrasonic elastography in clinical quantitative assessment of fatty liver

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM: To investigate the clinical application of ultrasonic elastography in quantitative assessment of fatty liver grading. METHODS: A total of 105 patients with fatty liver were divided into mild group (n = 46), moderate group (n = 39), and severe group (n = 20). Forty-five healthy individuals served as a normal control group. All patients who underwent routine ultrasound scan and further ultrasonic elastography were evaluated accordingly to the evaluation standards for ultrasonic elastography. The ratio of...

  12. Advanced RF-KO slow-extraction method for the reduction of spill ripple

    CERN Document Server

    Noda, K; Shibuya, S; Uesugi, T; Muramatsu, M; Kanazawa, M; Takada, E; Yamada, S

    2002-01-01

    Two advanced RF-knockout (RF-KO) slow-extraction methods have been developed at HIMAC in order to reduce the spill ripple for accurate heavy-ion cancer therapy: the dual frequency modulation (FM) method and the separated function method. As a result of simulations and experiments, it was verified that the spill ripple could be considerably reduced using these advanced methods, compared with the ordinary RF-KO method. The dual FM method and the separated function method bring about a low spill ripple within standard deviations of around 25% and of 15% during beam extraction within around 2 s, respectively, which are in good agreement with the simulation results.

  13. High temperature ultrasonic transducers: review

    OpenAIRE

    Kažys, R.; Voleišis, A.; Voleišienė, B.

    2008-01-01

    The problems of development of high-temperature ultrasonic transducers for modern science and technology applications are analysed. More than 10 piezoelectric materials suitable for operation at high temperatures are overviewed. It is shown that bismuth titanate based piezoelectric elements are most promisable. Bonding methods of piezoelectric elements to a protector and backing are discussed. Thermosonic gold-to-gold bonding is most modern and possesses unique features. Our achievements in t...

  14. Adherence to Scientific Method while Advancing Exposure Science

    Science.gov (United States)

    Paul Lioy was simultaneously a staunch adherent to the scientific method and an innovator of new ways to conduct science, particularly related to human exposure. Current challenges to science and the application of the scientific method are presented as they relate the approaches...

  15. Preface: Special Topic Section on Advanced Electronic Structure Methods for Solids and Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Michaelides, Angelos, E-mail: angelos.michaelides@ucl.ac.uk [London Centre for Nanotechnology and Department of Chemistry, University College London, London (United Kingdom); Martinez, Todd J. [Department of Chemistry and the PULSE Institute, Stanford University, Stanford, California 94305, USA and SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Alavi, Ali [Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569 Stuttgart, Germany and Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW (United Kingdom); Kresse, Georg [Faculty of Physics and Center for Computational Materials Science, Department of Physics, University of Vienna, Sensengasse 8/12, A-1090 Vienna (Austria); Manby, Frederick R. [Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TS (United Kingdom)

    2015-09-14

    This Special Topic section on Advanced Electronic Structure Methods for Solids and Surfaces contains a collection of research papers that showcase recent advances in the high accuracy prediction of materials and surface properties. It provides a timely snapshot of a growing field that is of broad importance to chemistry, physics, and materials science.

  16. Features of methods of advancement of information product in network the Interne

    Directory of Open Access Journals (Sweden)

    Oksentyuk, Roman Andriyovych

    2011-05-01

    Full Text Available In the article the features of construction of world network are considered the Internet as one of types of modern innovative technologies in marketing. His role is exposed in the modern world of entrepreneurial activity, most widespread methods of advancement of product by internet marketing. Pointed suggestion from advancement of informative product in a network the Internet.

  17. Preface: Special Topic Section on Advanced Electronic Structure Methods for Solids and Surfaces

    International Nuclear Information System (INIS)

    This Special Topic section on Advanced Electronic Structure Methods for Solids and Surfaces contains a collection of research papers that showcase recent advances in the high accuracy prediction of materials and surface properties. It provides a timely snapshot of a growing field that is of broad importance to chemistry, physics, and materials science

  18. Effect of side transmission of power ultrasonic on structure of AZ81 magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    张海波; 翟启杰; 戚飞鹏; 龚永勇

    2004-01-01

    In order to promote the application of power ultrasonic in metallurgic industry, ultrasonic vibration is introduced from the side of AZ81 ingot by adopting the automatic-attracting amplitude transformer horn which has independently been designed and produced, and the effect of the side transmission of ultrasonic on the solidification structure of metal is investigated. The results show that under this experimental condition, power ultrasonic can greatly improve the solidification structure of AZ81 magnesium alloy. Compared with the traditional modification methods in which inoculants are added into melt, power ultrasonic has a better performance. The present research gives us a new way for the application of ultrasonic refinement technique.

  19. Advanced methods for BWR transient and stability analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, A.; Wehle, F.; Opel, S.; Velten, R. [AREVA, AREVA NP, Erlangen (Germany)

    2008-07-01

    The design of advanced Boiling Water Reactor (BWR) fuel assemblies and cores is governed by the basic requirement of safe, reliable and flexible reactor operation with optimal fuel utilization. AREVA NP's comprehensive steady state and transient BWR methodology allows the designer to respond quickly and effectively to customer needs. AREVA NP uses S-RELAP5/RAMONA as the appropriate methodology for the representation of the entire plant. The 3D neutron kinetics and thermal-hydraulics code has been developed for the prediction of system, fuel and core behavior and provides additional margins for normal operation and transients. Of major importance is the extensive validation of the methodology. The validation is based on measurements at AREVA NP's test facilities, and comparison of the predictions with a great wealth of measured data gathered from BWR plants during many years of operation. Three of the main fields of interest are stability analysis, operational transients and reactivity initiated accidents (RIAs). The introduced 3D methodology for operational transients shows significant margin regarding the operational limit of critical power ratio, which has been approved by the German licensing authority. Regarding BWR stability a large number of measurements at different plants under various conditions have been performed and successfully post-calculated with RAMONA. This is the basis of reliable pre-calculations of the locations of regional and core-wide stability boundaries. (authors)

  20. Review: Advances in delta-subsidence research using satellite methods

    Science.gov (United States)

    Higgins, Stephanie A.

    2016-05-01

    Most of the world's major river deltas are sinking relative to local sea level. The effects of subsidence can include aquifer salinization, infrastructure damage, increased vulnerability to flooding and storm surges, and permanent inundation of low-lying land. Consequently, determining the relative importance of natural vs. anthropogenic pressures in driving delta subsidence is a topic of ongoing research. This article presents a review of knowledge with respect to delta surface-elevation loss. The field is rapidly advancing due to applications of space-based techniques: InSAR (interferometric synthetic aperture radar), GPS (global positioning system), and satellite ocean altimetry. These techniques have shed new light on a variety of subsidence processes, including tectonics, isostatic adjustment, and the spatial and temporal variability of sediment compaction. They also confirm that subsidence associated with fluid extraction can outpace sea-level rise by up to two orders of magnitude, resulting in effective sea-level rise that is one-hundred times faster than the global average rate. In coming years, space-based and airborne instruments will be critical in providing near-real-time monitoring to facilitate management decisions in sinking deltas. However, ground-based observations continue to be necessary for generating complete measurements of surface-elevation change. Numerical modeling should seek to simulate couplings between subsidence processes for greater predictive power.

  1. Advanced methods for BWR transient and stability analysis

    International Nuclear Information System (INIS)

    The design of advanced Boiling Water Reactor (BWR) fuel assemblies and cores is governed by the basic requirement of safe, reliable and flexible reactor operation with optimal fuel utilization. AREVA NP's comprehensive steady state and transient BWR methodology allows the designer to respond quickly and effectively to customer needs. AREVA NP uses S-RELAP5/RAMONA as the appropriate methodology for the representation of the entire plant. The 3D neutron kinetics and thermal-hydraulics code has been developed for the prediction of system, fuel and core behavior and provides additional margins for normal operation and transients. Of major importance is the extensive validation of the methodology. The validation is based on measurements at AREVA NP's test facilities, and comparison of the predictions with a great wealth of measured data gathered from BWR plants during many years of operation. Three of the main fields of interest are stability analysis, operational transients and reactivity initiated accidents (RIAs). The introduced 3D methodology for operational transients shows significant margin regarding the operational limit of critical power ratio, which has been approved by the German licensing authority. Regarding BWR stability a large number of measurements at different plants under various conditions have been performed and successfully post-calculated with RAMONA. This is the basis of reliable pre-calculations of the locations of regional and core-wide stability boundaries. (authors)

  2. Method of advancing research and development of fast breeder reactors

    International Nuclear Information System (INIS)

    In the long term plan of atomic energy development and utilization, fast breeder reactors are to be developed as the main of the future nuclear power generation in Japan, and when their development is advanced, it has been decided to positively aim at building up the plutonium utilization system using FBRs superior to the uranium utilization system using LWRs. Also it has been decided that the development of FBRs requires to exert incessant efforts for a considerable long period under the proper cooperation system of government and people, and as for its concrete development, hereafter the deliberation is to be carried out in succession by the expert subcommittee on FBR development projects of the Atomic Energy Commission. The subcommittee was founded in May, 1986, to deliberate on the long term promotion measures for FBR development, the measures for promoting the research and development, the examination of the basic specification of a demonstration FBR, the measures for promoting international cooperation, and other important matters. As the results of investigation, the situation around the development of FBRs, the fundamentals at the time of promoting the research and development, the subjects of the research and development and so on are reported. (Kako, I.)

  3. Comparative study of various PKINIT methods used in Advanced Kerberos

    Directory of Open Access Journals (Sweden)

    Shital S. Thorat,

    2010-10-01

    Full Text Available Traditional authentication method is password, but it cannot resist dictionary and playback attack. Thus, applications, which send an unencrypted password over the network, are extremely vulnerable. Kerberos can be used as a solution to these network security problems. The Kerberos protocol with public key cryptography may help client to prove its identity to a server (and vice-versa across an insecurenetwork connection. This paper shows comparative study of various PKINIT methods used in Kerberos with their results.

  4. Advances in spectroscopic methods for quantifying soil carbon

    Science.gov (United States)

    Reeves, James B., III; McCarty, Gregory W.; Calderon, Francisco; Hively, W. Dean

    2012-01-01

    The current gold standard for soil carbon (C) determination is elemental C analysis using dry combustion. However, this method requires expensive consumables, is limited by the number of samples that can be processed (~100/d), and is restricted to the determination of total carbon. With increased interest in soil C sequestration, faster methods of analysis are needed, and there is growing interest in methods based on diffuse reflectance spectroscopy in the visible, near-infrared or mid-infrared spectral ranges. These spectral methods can decrease analytical requirements and speed sample processing, be applied to large landscape areas using remote sensing imagery, and be used to predict multiple analytes simultaneously. However, the methods require localized calibrations to establish the relationship between spectral data and reference analytical data, and also have additional, specific problems. For example, remote sensing is capable of scanning entire watersheds for soil carbon content but is limited to the surface layer of tilled soils and may require difficult and extensive field sampling to obtain proper localized calibration reference values. The objective of this chapter is to discuss the present state of spectroscopic methods for determination of soil carbon.

  5. Viscous-Inviscid Coupling Methods for Advanced Marine Propeller Applications

    Directory of Open Access Journals (Sweden)

    Martin Greve

    2012-01-01

    Full Text Available The paper reports the development of coupling strategies between an inviscid direct panel method and a viscous RANS method and their application to complex propeller ows. The work is motivated by the prohibitive computational cost associated to unsteady viscous flow simulations using geometrically resolved propellers to analyse the dynamics of ships in seaways. The present effort aims to combine the advantages of the two baseline methods in order to reduce the numerical effort without compromising the predictive accuracy. Accordingly, the viscous method is used to calculate the global flow field, while the inviscid method predicts the forces acting on the propeller. The corresponding reaction forces are employed as body forces to mimic the propeller influence on the viscous flow field. Examples included refer to simple verification cases for an isolated propeller blade, open-water validation simulations for a complete propeller, and more challenging investigations of a manoeuvring vessel in seaways. Reported results reveal a fair predictive agreement between the coupled approach and fully viscous simulations and display the efficiency of the coupled approach.

  6. Ultrasonic flow measurements for irrigation process monitoring

    Science.gov (United States)

    Ziani, Elmostafa; Bennouna, Mustapha; Boissier, Raymond

    2004-02-01

    This paper presents the state of the art of the general principle of liquid flow measurements by ultrasonic method, and problems of flow measurements. We present an ultrasonic flowmeter designed according to smart sensors concept, for the measurement of irrigation water flowing through pipelines or open channels, using the ultrasonic transit time approach. The new flowmeter works on the principle of measuring time delay differences between sound pulses transmitted upstream and downstream in the flowing liquid. The speed of sound in the flowing medium is eliminated as a variable because the flowrate calculations are based on the reciprocals of the transmission times. The transit time difference is digitally measured by means of a suitable, microprocessor controlled logic. This type of ultrasonic flowmeter will be widely used in industry and water management, it is well studied in this work, followed by some experimental results. For pressurized channels, we use one pair of ultrasonic transducer arranged in proper positions and directions of the pipe, in this case, to determine the liquid velocity, a real time on-line analysis taking account the geometries of the hydraulic system, is applied to the obtained ultrasonic data. In the open channels, we use a single or two pairs of ultrasonic emitter-receiver according to the desired performances. Finally, the goals of this work consist in integrating the smart sensor into irrigation systems monitoring in order to evaluate potential advantages and demonstrate their performance, on the other hand, to understand and use ultrasonic approach for determining flow characteristics and improving flow measurements by reducing errors caused by disturbances of the flow profiles.

  7. A Novel Advanced Heap Corruption and Security Method

    Directory of Open Access Journals (Sweden)

    Arundhati Walia

    2012-05-01

    Full Text Available Heap security has been a major concern since the past two decades. Recently many methods have been proposed to secure heap i.e. to avoid heap overrun and attacks. The paper describes a method suggested to secure heap at the operating system level. Major emphasis is given to Solaris operating systems dynamic memory manager. When memory is required dynamically during runtime, the SysVmalloc acts as a memory allocator.Vmalloc allocates the chunks of memory in the form of splay tree structure. A self adjusting binary tree structure is reviewed in the paper, moreover major security issue to secure heap area is also suggested in the paper.

  8. Advance in research on aerosol deposition simulation methods

    International Nuclear Information System (INIS)

    A comprehensive analysis of the health effects of inhaled toxic aerosols requires exact data on airway deposition. A knowledge of the effect of inhaled drugs is essential to the optimization of aerosol drug delivery. Sophisticated analytical deposition models can be used for the computation of total, regional and generation specific deposition efficiencies. The continuously enhancing computer seem to allow us to study the particle transport and deposition in more and more realistic airway geometries with the help of computational fluid dynamics (CFD) simulation method. In this article, the trends in aerosol deposition models and lung models, and the methods for achievement of deposition simulations are also reviewed. (authors)

  9. Advanced FDTD methods parallelization, acceleration, and engineering applications

    CERN Document Server

    Yu, Wenhua

    2011-01-01

    The finite-difference time-domain (FDTD) method has revolutionized antenna design and electromagnetics engineering. Here's a cutting-edge book that focuses on the performance optimization and engineering applications of FDTD simulation systems. Covering the latest developments in this area, this unique resource offer you expert advice on the FDTD method, hardware platforms, and network systems. Moreover the book offers guidance in distinguishing between the many different electromagnetics software packages on the market today. You also find a complete chapter dedicated to large multi-scale pro

  10. System and technique for ultrasonic determination of degree of cooking

    Science.gov (United States)

    Bond, Leonard J.; Diaz, Aaron A.; Judd, Kayte M.; Pappas, Richard A.; Cliff, William C.; Pfund, David M.; Morgen, Gerald P.

    2007-03-20

    A method and apparatus are described for determining the doneness of food during a cooking process. Ultrasonic signal are passed through the food during cooking. The change in transmission characteristics of the ultrasonic signal during the cooking process is measured to determine the point at which the food has been cooked to the proper level. In one aspect, a heated fluid cooks the food, and the transmission characteristics along a fluid-only ultrasonic path provides a reference for comparison with the transmission characteristics for a food-fluid ultrasonic path.

  11. Recent advances in chemical engineering. Tracers and tracing methods

    International Nuclear Information System (INIS)

    The first congress on 'tracers and tracing methods' has taken place in Nancy in November 1998. It has been a successful national event with more than 100 participants and 65 presentations. The applications of radiotracers in different industries have been studied. The target participants were the researchers, engineers and technologists of various industrial and research sectors

  12. Advanced Control Methods for Optimization of Arc Welding

    DEFF Research Database (Denmark)

    Thomsen, J. S.

    Gas Metal Arc Welding (GMAW) is a proces used for joining pieces of metal. Probably, the GMAW process is the most successful and widely used welding method in the industry today. A key issue in welding is the quality of the welds produced. The quality of a weld is influenced by several factors...

  13. Advances in methods for colour marking of mosquitoes

    NARCIS (Netherlands)

    Verhulst, N.O.; Loonen, J.A.C.M.; Takken, W.

    2013-01-01

    Background: Different techniques are available for colour marking insects and each technique may be suitable for different insect species. Mosquitoes can be marked to determine population size, distribution and flight distance or distinguish closely related species. In this study, two methods of col

  14. Advancing Analytical Methods for Characterization of Anionic Carbohydrate Biopolymers

    OpenAIRE

    Langeslay, Derek Joseph

    2013-01-01

    The focus of this dissertation is on the development of improved analytical methods for the characterization of anionic carbohydrate biopolymers. Our goal is to extract important information from complex mixtures of heterogeneous polysaccharides by characterizing their substituent oligosaccharides in terms of monosaccharide composition and primary and secondary structure. This work focuses on the application of two major analytical platforms: spectroscopy and chromatography. The development ...

  15. Method of public support evaluation for advanced NPP deployment

    International Nuclear Information System (INIS)

    Public support of nuclear power could be fully recovered only if the public would, from the very beginning of the new power source selection process, receive transparent information and was made a part of interactive dialogue. The presented method was developed with the objective to facilitate the complex process of the utilities - public interaction. Our method of the public support evaluation allows to classify designs of new nuclear power plants taking into consideration the public attitude to continued nuclear power deployment in the Czech Republic as well as the preference of a certain plant design. The method is based on the model with a set of probabilistic input metrics, which permits to compare the offered concepts with the reference one, with a high degree of objectivity. This method is a part of the more complex evaluation procedure applicable for the new designs assessment that uses the computer code ''Potencial'' developed at the NRI Rez plc. The metrics of the established public support criteria are discussed. (author)

  16. Origins, Methods and Advances in Qualitative Meta-Synthesis

    Science.gov (United States)

    Nye, Elizabeth; Melendez-Torres, G. J.; Bonell, Chris

    2016-01-01

    Qualitative research is a broad term encompassing many methods. Critiques of the field of qualitative research argue that while individual studies provide rich descriptions and insights, the absence of connections drawn between studies limits their usefulness. In response, qualitative meta-synthesis serves as a design to interpret and synthesise…

  17. A comparative study of ultrasonic direct contact, immersion, and layer resonance methods for assessment of enamel thickness in teeth

    OpenAIRE

    Dwyer-Joyce, R.S.; Goodman, M A; Lewis, R.

    2010-01-01

    Wear of dental enamel is a growing problem, but is clinically difficult to diagnose and monitor. An accurate and easy-to-use non-destructive method for the measurement of enamel thickness would be useful for early diagnosis of enamel loss and for monitoring progression. Ultrasound has been identified by several researchers as a potential tool suitable for enamel thickness measurement. However, in vitro studies have shown that while the method is feasible, it suffers from wide variability. The...

  18. Advanced discretizations and multigrid methods for liquid crystal configurations

    Science.gov (United States)

    Emerson, David B.

    Liquid crystals are substances that possess mesophases with properties intermediate between liquids and crystals. Here, we consider nematic liquid crystals, which consist of rod-like molecules whose average pointwise orientation is represented by a unit-length vector, n( x, y, z) = (n1, n 2, n3)T. In addition to their self-structuring properties, nematics are dielectrically active and birefringent. These traits continue to lead to many important applications and discoveries. Numerical simulations of liquid crystal configurations are used to suggest the presence of new physical phenomena, analyze experiments, and optimize devices. This thesis develops a constrained energy-minimization finite-element method for the efficient computation of nematic liquid crystal equilibrium configurations based on a Lagrange multiplier formulation and the Frank-Oseen free-elastic energy model. First-order optimality conditions are derived and linearized via a Newton approach, yielding a linear system of equations. Due to the nonlinear unit-length constraint, novel well-posedness theory for the variational systems, as well as error analysis, is conducted. The approach is shown to constitute a convergent and well-posed approach, absent typical simplifying assumptions. Moreover, the energy-minimization method and well-posedness theory developed for the free-elastic case are extended to include the effects of applied electric fields and flexoelectricity. In the computational algorithm, nested iteration is applied and proves highly effective at reducing computational costs. Additionally, an alternative technique is studied, where the unit-length constraint is imposed by a penalty method. The performance of the penalty and Lagrange multiplier methods is compared. Furthermore, tailored trust-region strategies are introduced to improve robustness and efficiency. While both approaches yield effective algorithms, the Lagrange multiplier method demonstrates superior accuracy per unit cost. In

  19. Extraction of Solanesol by Ultrasonic-microwave Synergistic Saponification Method%超声-微波协同皂化萃取茄尼醇条件的研究

    Institute of Scientific and Technical Information of China (English)

    鄢贵龙; 刘爱云

    2011-01-01

    实验研究了超声-微波协同皂化萃取茄尼醇的工艺条件,确定了其最适工艺参数为:在超声开的条件下,皂化时间60 min,微波功率40 W,氢氧化钠与烟叶浸膏的质量比为1∶2,在此优化条件下茄尼醇皂化回收率为126.3%.与其它皂化法相比,超声-微波协同皂化萃取法具有节省时间、节约能量、茄尼醇回收率高等优点.%Ultrasonic-microwave synergistic saponification technique was applied to extract solanesol. The effects of main factors on saponification reaction were discussed and the optimum saponification conditions were as followed:the saponification time was 60 min, the microwave power was 40 W, the mass ratio of sodium hydroxide to tobacco extract was 1: 2,and the ultrasonic was turned on. The results showed that under the optimized condition, the recovery rate of sulanesol was 126.3%. Compared with other saponification methods, the ultrasonic-microwave synergistic saponification technique was a better method for solanesol extraction with less time and higher recovery rate of solanesol.

  20. Advance of Therapeutic Methods for Malignant Pleural Effusion

    Institute of Scientific and Technical Information of China (English)

    XU Tao-tao

    2016-01-01

    Malignant pleural effusion (MPE) is a condition caused by primary malignant tumors in the pleura or other malignant tumors metastasis to the pleura. It is also one of common serious complications of middle-late malignant tumor, which has severe impact on the quality of life, even threatening the life of the patients. The selection of treatments for MPE depends on many factors, including the symptoms, performance status, primary tumor types, response to systemic therapy, and degree of lung recruitment maneuvers (LRM) after drainage of pleural effusion. Generally, the treatment methods include thoracentesis, indwelling pleural catheter, pleurodesis, intrapleural injection of drugs, chemotherapy, radiotherapy, anti-angiogenesis therapy, surgery, and thermotherapy. With the in-depth study on pathogenesis of MPE, the treatments of MPE have continuous improvements. This study mainly reviewed the treatment methods for MPE so as to provide the basis for clinical practice in the future.