WorldWideScience

Sample records for electronic transformer based

  1. Power Electronic Transformer based Three-Phase PWM AC Drives

    Science.gov (United States)

    Basu, Kaushik

    A Transformer is used to provide galvanic isolation and to connect systems at different voltage levels. It is one of the largest and most expensive component in most of the high voltage and high power systems. Its size is inversely proportional to the operating frequency. The central idea behind a power electronic transformer (PET) also known as solid state transformer is to reduce the size of the transformer by increasing the frequency. Power electronic converters are used to change the frequency of operation. Steady reduction in the cost of the semiconductor switches and the advent of advanced magnetic materials with very low loss density and high saturation flux density implies economic viability and feasibility of a design with high power density. Application of PET is in generation of power from renewable energy sources, especially wind and solar. Other important application include grid tied inverters, UPS e.t.c. In this thesis non-resonant, single stage, bi-directional PET is considered. The main objective of this converter is to generate adjustable speed and magnitude pulse width modulated (PWM) ac waveforms from an ac or dc grid with a high frequency ac link. The windings of a high frequency transformer contains leakage inductance. Any switching transition of the power electronic converter connecting the inductive load and the transformer requires commutation of leakage energy. Commutation by passive means results in power loss, decrease in the frequency of operation, distortion in the output voltage waveform, reduction in reliability and power density. In this work a source based partially loss-less commutation of leakage energy has been proposed. This technique also results in partial soft-switching. A series of converters with novel PWM strategies have been proposed to minimize the frequency of leakage inductance commutation. These PETs achieve most of the important features of modern PWM ac drives including 1) Input power factor correction, 2) Common

  2. Flexible Electronics-Based Transformers for Extreme Environments

    Science.gov (United States)

    Quadrelli, Marco B.; Stoica, Adrian; Ingham, Michel; Thakur, Anubhav

    2015-01-01

    This paper provides a survey of the use of modular multifunctional systems, called Flexible Transformers, to facilitate the exploration of extreme and previously inaccessible environments. A novel dynamics and control model of a modular algorithm for assembly, folding, and unfolding of these innovative structural systems is also described, together with the control model and the simulation results.

  3. Transformational silicon electronics

    KAUST Repository

    Rojas, Jhonathan Prieto

    2014-02-25

    In today\\'s traditional electronics such as in computers or in mobile phones, billions of high-performance, ultra-low-power devices are neatly integrated in extremely compact areas on rigid and brittle but low-cost bulk monocrystalline silicon (100) wafers. Ninety percent of global electronics are made up of silicon. Therefore, we have developed a generic low-cost regenerative batch fabrication process to transform such wafers full of devices into thin (5 μm), mechanically flexible, optically semitransparent silicon fabric with devices, then recycling the remaining wafer to generate multiple silicon fabric with chips and devices, ensuring low-cost and optimal utilization of the whole substrate. We show monocrystalline, amorphous, and polycrystalline silicon and silicon dioxide fabric, all from low-cost bulk silicon (100) wafers with the semiconductor industry\\'s most advanced high-κ/metal gate stack based high-performance, ultra-low-power capacitors, field effect transistors, energy harvesters, and storage to emphasize the effectiveness and versatility of this process to transform traditional electronics into flexible and semitransparent ones for multipurpose applications. © 2014 American Chemical Society.

  4. Coordinate transformation based cryo-correlative methods for electron tomography and focused ion beam milling

    International Nuclear Information System (INIS)

    Fukuda, Yoshiyuki; Schrod, Nikolas; Schaffer, Miroslava; Feng, Li Rebekah; Baumeister, Wolfgang; Lucic, Vladan

    2014-01-01

    Correlative microscopy allows imaging of the same feature over multiple length scales, combining light microscopy with high resolution information provided by electron microscopy. We demonstrate two procedures for coordinate transformation based correlative microscopy of vitrified biological samples applicable to different imaging modes. The first procedure aims at navigating cryo-electron tomography to cellular regions identified by fluorescent labels. The second procedure, allowing navigation of focused ion beam milling to fluorescently labeled molecules, is based on the introduction of an intermediate scanning electron microscopy imaging step to overcome the large difference between cryo-light microscopy and focused ion beam imaging modes. These methods make it possible to image fluorescently labeled macromolecular complexes in their natural environments by cryo-electron tomography, while minimizing exposure to the electron beam during the search for features of interest. - Highlights: • Correlative light microscopy and focused ion beam milling of vitrified samples. • Coordinate transformation based cryo-correlative method. • Improved correlative light microscopy and cryo-electron tomography

  5. Transformational III-V Electronics

    KAUST Repository

    Nour, Maha A.

    2014-04-01

    Flexible electronics using III-V materials for nano-electronics with high electron mobility and optoelectronics with direct band gap are attractive for many applications. This thesis describes a complementary metal oxide semiconductor (CMOS) compatible process for transforming traditional III-V materials based electronics into flexible one. The thesis reports releasing 200 nm of Gallium Arsenide (GaAs) from 200 nm GaAs / 300 nm Aluminum Arsenide (AlAs) stack on GaAs substrate using diluted hydrofluoric acid (HF). This process enables releasing a single top layer compared to peeling off all layers with small sizes at the same time. This is done utilizing a network of release holes that contributes to the better transparency (45 % at 724 nm wavelengths) observed. Fabrication of metal oxide semiconductor capacitor (MOSCAPs) on GaAs is followed by releasing it to have devices on flexible 200 nm GaAs. Similarly, flexible GaSb and InP fabrication process is also reported to transform traditional electronics into large-area flexible electronics.

  6. A Redundancy Mechanism Design for Hall-Based Electronic Current Transformers

    Directory of Open Access Journals (Sweden)

    Kun-Long Chen

    2017-03-01

    Full Text Available Traditional current transformers (CTs suffer from DC and AC saturation and remanent magnetization in many industrial applications. Moreover, the drawbacks of traditional CTs, such as closed iron cores, bulky volume, and heavy weight, further limit the development of an intelligent power protection system. In order to compensate for these drawbacks, we proposed a novel current measurement method by using Hall sensors, which is called the Hall-effect current transformer (HCT. The existing commercial Hall sensors are electronic components, so the reliability of the HCT is normally worse than that of the traditional CT. Therefore, our study proposes a redundancy mechanism for the HCT to strengthen its reliability. With multiple sensor modules, the method has the ability to improve the accuracy of the HCT as well. Additionally, the proposed redundancy mechanism monitoring system provides a condition-based maintenance for the HCT. We verify our method with both simulations and an experimental test. The results demonstrate that the proposed HCT with a redundancy mechanism can almost achieve Class 0.2 for measuring CTs according to IEC Standard 60044-8.

  7. Performance analysis of electronic power transformer based on neuro-fuzzy controller.

    Science.gov (United States)

    Acikgoz, Hakan; Kececioglu, O Fatih; Yildiz, Ceyhun; Gani, Ahmet; Sekkeli, Mustafa

    2016-01-01

    In recent years, electronic power transformer (EPT), which is also called solid state transformer, has attracted great interest and has been used in place of the conventional power transformers. These transformers have many important functions as high unity power factor, low harmonic distortion, constant DC bus voltage, regulated output voltage and compensation capability. In this study, proposed EPT structure contains a three-phase pulse width modulation rectifier that converts 800 Vrms AC to 2000 V DC bus at input stage, a dual active bridge converter that provides 400 V DC bus with 5:1 high frequency transformer at isolation stage and a three-phase two level inverter that is used to obtain AC output at output stage. In order to enhance dynamic performance of EPT structure, neuro fuzzy controllers which have durable and nonlinear nature are used in input and isolation stages instead of PI controllers. The main aim of EPT structure with the proposed controller is to improve the stability of power system and to provide faster response against disturbances. Moreover, a number of simulation results are carried out to verify EPT structure designed in MATLAB/Simulink environment and to analyze compensation ability for voltage harmonics, voltage flicker and voltage sag/swell conditions.

  8. An accurate online calibration system based on combined clamp-shape coil for high voltage electronic current transformers.

    Science.gov (United States)

    Li, Zhen-hua; Li, Hong-bin; Zhang, Zhi

    2013-07-01

    Electronic transformers are widely used in power systems because of their wide bandwidth and good transient performance. However, as an emerging technology, the failure rate of electronic transformers is higher than that of traditional transformers. As a result, the calibration period needs to be shortened. Traditional calibration methods require the power of transmission line be cut off, which results in complicated operation and power off loss. This paper proposes an online calibration system which can calibrate electronic current transformers without power off. In this work, the high accuracy standard current transformer and online operation method are the key techniques. Based on the clamp-shape iron-core coil and clamp-shape air-core coil, a combined clamp-shape coil is designed as the standard current transformer. By analyzing the output characteristics of the two coils, the combined clamp-shape coil can achieve verification of the accuracy. So the accuracy of the online calibration system can be guaranteed. Moreover, by employing the earth potential working method and using two insulating rods to connect the combined clamp-shape coil to the high voltage bus, the operation becomes simple and safe. Tests in China National Center for High Voltage Measurement and field experiments show that the proposed system has a high accuracy of up to 0.05 class.

  9. An accurate online calibration system based on combined clamp-shape coil for high voltage electronic current transformers

    International Nuclear Information System (INIS)

    Li, Zhen-hua; Li, Hong-bin; Zhang, Zhi

    2013-01-01

    Electronic transformers are widely used in power systems because of their wide bandwidth and good transient performance. However, as an emerging technology, the failure rate of electronic transformers is higher than that of traditional transformers. As a result, the calibration period needs to be shortened. Traditional calibration methods require the power of transmission line be cut off, which results in complicated operation and power off loss. This paper proposes an online calibration system which can calibrate electronic current transformers without power off. In this work, the high accuracy standard current transformer and online operation method are the key techniques. Based on the clamp-shape iron-core coil and clamp-shape air-core coil, a combined clamp-shape coil is designed as the standard current transformer. By analyzing the output characteristics of the two coils, the combined clamp-shape coil can achieve verification of the accuracy. So the accuracy of the online calibration system can be guaranteed. Moreover, by employing the earth potential working method and using two insulating rods to connect the combined clamp-shape coil to the high voltage bus, the operation becomes simple and safe. Tests in China National Center for High Voltage Measurement and field experiments show that the proposed system has a high accuracy of up to 0.05 class

  10. Research on Harmonic Characteristic of Electronic Current Transformer Based on the Rogowski Coil

    Science.gov (United States)

    Shen, Diqiu; Hu, Bei; Wang, Xufeng; Zhu, Mingdong; Wang, Liang; Lu, Wenxing

    2017-05-01

    The nonlinear load present in the power system will cause the distortion of AC sine wave and generate the harmonic, which havea severe impact on the accuracy of energy metering and reliability of relay protection. Tosatisfy the requirements of energy metering and relay protection for the new generation of intelligent substation, based on the working principle of Rogowski coil current transformer, mathematical model and transfer characteristics of Rogowski coil sensors were studied in this paper, and frequency response characteristics of Rogowski coil current transformer system were analysed. Finally, the frequency response characteristics of the Rogowski coil current transformer at 2 to 13 harmonics was simulated and experimented. Simulation and experiments show that Rogowski coil current transformer couldmeet 0.2 accuracy requirements of harmonic power measurement of power system, and measure the harmonic components of the grid reliably.

  11. Research on Electronic Transformer Data Synchronization Based on Interpolation Methods and Their Error Analysis

    Directory of Open Access Journals (Sweden)

    Pang Fubin

    2015-09-01

    Full Text Available In this paper the origin problem of data synchronization is analyzed first, and then three common interpolation methods are introduced to solve the problem. Allowing for the most general situation, the paper divides the interpolation error into harmonic and transient interpolation error components, and the error expression of each method is derived and analyzed. Besides, the interpolation errors of linear, quadratic and cubic methods are computed at different sampling rates, harmonic orders and transient components. Further, the interpolation accuracy and calculation amount of each method are compared. The research results provide theoretical guidance for selecting the interpolation method in the data synchronization application of electronic transformer.

  12. Transformational silicon electronics

    KAUST Repository

    Rojas, Jhonathan Prieto; Sevilla, Galo T.; Ghoneim, Mohamed T.; Inayat, Salman Bin; Ahmed, Sally; Hussain, Aftab M.; Hussain, Muhammad Mustafa

    2014-01-01

    In today's traditional electronics such as in computers or in mobile phones, billions of high-performance, ultra-low-power devices are neatly integrated in extremely compact areas on rigid and brittle but low-cost bulk monocrystalline silicon (100

  13. Electronic voltage and current transformers testing device.

    Science.gov (United States)

    Pan, Feng; Chen, Ruimin; Xiao, Yong; Sun, Weiming

    2012-01-01

    A method for testing electronic instrument transformers is described, including electronic voltage and current transformers (EVTs, ECTs) with both analog and digital outputs. A testing device prototype is developed. It is based on digital signal processing of the signals that are measured at the secondary outputs of the tested transformer and the reference transformer when the same excitation signal is fed to their primaries. The test that estimates the performance of the prototype has been carried out at the National Centre for High Voltage Measurement and the prototype is approved for testing transformers with precision class up to 0.2 at the industrial frequency (50 Hz or 60 Hz). The device is suitable for on-site testing due to its high accuracy, simple structure and low-cost hardware.

  14. Electronic Power Transformer for Power Distribution Networks

    Directory of Open Access Journals (Sweden)

    Ermuraсhi Iu.V.

    2017-12-01

    Full Text Available Reducing losses in electricity distribution networks is a current technical problem. This issue also has social and environmental aspects. As a promising solution one can examine the direct distribution from the medium voltage power network using new equipment based on the use of power electronics. The aim of the paper is to propose and argue an innovative technical solution for the realization of the Solid State Transformer (SST in order to decrease the number of energy transformation stages compared to the known solutions, simplifying the topology of the functional scheme with the reduction of production costs and the loss of energy in transformers used in electrical distribution networks. It is proposed the solution of simplifying the topology of the AC/AC electronic transformer by reducing the number of passive electronic components (resistors, inductors, capacitors and active (transistors. The inverter of the SST transformer ensures the switching mode of the transistors, using for this purpose the inductance of the magnetic leakage flux of the high frequency transformer. The robustness of the laboratory sample of the SST 10 / 0.22 kV transformer with the power of 20 kW was manufactured and tested. Testing of the laboratory sample confirmed the functionality of the proposed scheme and the possibility of switching of the transistors to at zero current (ZCS mode with the reduction of the energy losses. In the proposed converter a single high-frequency transformer with a simplified construction with two windings is used, which reduces its mass and the cost of making the transformer. The reduction in the manufacturing cost of the converter is also due to the decrease in the number of links between the functional elements.

  15. Transformational electronics are now reconfiguring

    KAUST Repository

    Rojas, Jhonathan Prieto; Hussain, Aftab M.; Carreno, Armando Arpys Arevalo; Foulds, I. G.; Sevilla, Galo T.; Nassar, Joanna M.; Hussain, Muhammad Mustafa

    2015-01-01

    enhanced electronic systems for application in entertainment, healthcare, fitness and wellness, military and manufacturing industry. Based on these novel structural designs we have developed a siliconbased network of hexagonal islands connected through

  16. Monitoring the metering performance of an electronic voltage transformer on-line based on cyber-physics correlation analysis

    International Nuclear Information System (INIS)

    Zhang, Zhu; Li, Hongbin; Hu, Chen; Jiao, Yang; Tang, Dengping

    2017-01-01

    Metering performance is the key parameter of an electronic voltage transformer (EVT), and it requires high accuracy. The conventional off-line calibration method using a standard voltage transformer is not suitable for the key equipment in a smart substation, which needs on-line monitoring. In this article, we propose a method for monitoring the metering performance of an EVT on-line based on cyber-physics correlation analysis. By the electrical and physical properties of a substation running in three-phase symmetry, the principal component analysis method is used to separate the metering deviation caused by the primary fluctuation and the EVT anomaly. The characteristic statistics of the measured data during operation are extracted, and the metering performance of the EVT is evaluated by analyzing the change in statistics. The experimental results show that the method successfully monitors the metering deviation of a Class 0.2 EVT accurately. The method demonstrates the accurate evaluation of on-line monitoring of the metering performance on an EVT without a standard voltage transformer. (paper)

  17. Monitoring the metering performance of an electronic voltage transformer on-line based on cyber-physics correlation analysis

    Science.gov (United States)

    Zhang, Zhu; Li, Hongbin; Tang, Dengping; Hu, Chen; Jiao, Yang

    2017-10-01

    Metering performance is the key parameter of an electronic voltage transformer (EVT), and it requires high accuracy. The conventional off-line calibration method using a standard voltage transformer is not suitable for the key equipment in a smart substation, which needs on-line monitoring. In this article, we propose a method for monitoring the metering performance of an EVT on-line based on cyber-physics correlation analysis. By the electrical and physical properties of a substation running in three-phase symmetry, the principal component analysis method is used to separate the metering deviation caused by the primary fluctuation and the EVT anomaly. The characteristic statistics of the measured data during operation are extracted, and the metering performance of the EVT is evaluated by analyzing the change in statistics. The experimental results show that the method successfully monitors the metering deviation of a Class 0.2 EVT accurately. The method demonstrates the accurate evaluation of on-line monitoring of the metering performance on an EVT without a standard voltage transformer.

  18. Transformational III-V Electronics

    KAUST Repository

    Nour, Maha A.

    2014-01-01

    Flexible electronics using III-V materials for nano-electronics with high electron mobility and optoelectronics with direct band gap are attractive for many applications. This thesis describes a complementary metal oxide semiconductor (CMOS

  19. Transformational electronics are now reconfiguring

    KAUST Repository

    Rojas, Jhonathan Prieto

    2015-05-22

    Current developments on enhancing our smart living experience are leveraging the increased interest for novel systems that can be compatible with foldable, wrinkled, wavy and complex geometries and surfaces, and thus become truly ubiquitous and easy to deploy. Therefore, relying on innovative structural designs we have been able to reconfigure the physical form of various materials, to achieve remarkable mechanical flexibility and stretchability, which provides us with the perfect platform to develop enhanced electronic systems for application in entertainment, healthcare, fitness and wellness, military and manufacturing industry. Based on these novel structural designs we have developed a siliconbased network of hexagonal islands connected through double-spiral springs, forming an ultra-stretchable (~1000%) array for full compliance to highly asymmetric shapes and surfaces, as well as a serpentine design used to show an ultrastretchable (~800%) and flexible, spatially reconfigurable, mobile, metallic thin film copper (Cu)-based, body-integrated and non-invasive thermal heater with wireless controlling capability, reusability, heating-adaptability and affordability due to low-cost complementary metal oxide semiconductor (CMOS)-compatible integration. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  20. Tesla-transformer-type electron beam accelerator

    International Nuclear Information System (INIS)

    Liu Jinliang; Zhong Huihuang; Tan Qimei; Li Chuanlu; Zhang Jiande

    2002-01-01

    An electron-beam Tesla-transformer accelerator is described. It consists of the primary storage energy system. Tesla transformer, oil Blumlein pulse form line, and the vacuum diode. The experiments of initial stage showed that diode voltage rises up to about 500 kV with an input of 20 kV and the maximum electron-beam current is about 9 kA, the pulse width is about 50 ns. This device can operate stably and be set up easily

  1. Electronic tap-changer for distribution transformers

    CERN Document Server

    Faiz, Jawad

    2011-01-01

    This reference collects all relevant aspects electronic tap-changer and presents them in a comprehensive and orderly manner. It explains logically and systematically the design and optimization of a full electronic tap-changer for distribution transformers. The book provides a fully new insight to all possible structures of power section design and categorizes them comprehensively, including cost factors of the design. In the control section design, the authors review mechanical tap-changer control systems and they present the modeling of a full electronic tap-changer as well as a closed-loop

  2. Electronic tap-changer for distribution transformers

    Energy Technology Data Exchange (ETDEWEB)

    Faiz, Jawad [Tehran Univ. (Iran, Islamic Republic of). Univ. College of Engineering; Siahkolah, Behzad [Kavandish Company, Tehran (Iran, Islamic Republic of)

    2011-07-01

    This reference collects all relevant aspects electronic tap-changer and presents them in a comprehensive and orderly manner. It explains logically and systematically the design and optimization of a full electronic tap-changer for distribution transformers. The book provides a fully new insight to all possible structures of power section design and categorizes them comprehensively, including cost factors of the design. In the control section design, the authors review mechanical tap-changer control systems and they present the modeling of a full electronic tap-changer as well as a closed-loop control of the full-electronic tap-changer. The book is written for electrical engineers in industry and academia but should be useful also to postgraduate students of electrical engineering. (orig.)

  3. Electron-irradiation-induced phase transformation in alumina

    International Nuclear Information System (INIS)

    Chen, C.L.; Arakawa, K.; Lee, J.-G.; Mori, H.

    2010-01-01

    In this study, electron-irradiation-induced phase transformations between alumina polymorphs were investigated by high-resolution transmission electron microscopy. It was found that the electron-irradiation-induced α → κ' phase transformation occurred in the alumina under 100 keV electron irradiation. It is likely that the knock-on collision between incident electrons and Al 3+ cations is responsible for the occurrence of electron-irradiation-induced phase transformation from α-alumina to κ'-alumina.

  4. Positron depth profiling of the structural and electronic structure transformations of hydrogenated Mg-based thin films

    Science.gov (United States)

    Eijt, S. W. H.; Kind, R.; Singh, S.; Schut, H.; Legerstee, W. J.; Hendrikx, R. W. A.; Svetchnikov, V. L.; Westerwaal, R. J.; Dam, B.

    2009-02-01

    We report positron depth-profiling studies on the hydrogen sorption behavior and phase evolution of Mg-based thin films. We show that the main changes in the depth profiles resulting from the hydrogenation to the respective metal hydrides are related to a clear broadening in the observed electron momentum densities in both Mg and Mg2Ni films. This shows that positron annihilation methods are capable of monitoring these metal-to-insulator transitions, which form the basis for important applications of these types of films in switchable mirror devices and hydrogen sensors in a depth-sensitive manner. Besides, some of the positrons trap at the boundaries of columnar grains in the otherwise nearly vacancy-free Mg films. The combination of positron annihilation and x-ray diffraction further shows that hydrogen loading at elevated temperatures, in the range of 480-600 K, leads to a clear Pd-Mg alloy formation of the Pd catalyst cap layer. At the highest temperatures, the hydrogenation induces a partial delamination of the ˜5 nm thin capping layer, as sensitively monitored by positron depth profiling of the fraction of ortho-positronium formed at interface with the cap layer. The delamination effectively blocks the hydrogen cycling. In Mg-Si bilayers, we investigated the reactivity upon hydrogen loading and heat treatments near 480 K, which shows that Mg2Si formation is fast relative to MgH2. The combination of positron depth profiling and transmission electron microscopy shows that hydrogenation promotes a complete conversion to Mg2Si for this destabilized metal hydride system, while a partially unreacted, Mg-rich amorphous prelayer remains on top of Mg2Si after a single heat treatment in an inert gas environment. Thin film studies indicate that the difficulty of rehydrogenation of Mg2Si is not primarily the result from slow hydrogen dissociation at surfaces, but is likely hindered by the presence of a barrier for removal of Mg from the readily formed Mg2Si.

  5. Research on lightning stroke model and characteristics of electronic transformer

    Directory of Open Access Journals (Sweden)

    Li Mu

    2018-01-01

    Full Text Available In order to improve the reliability of power supply, a large number of electronic voltage and current transformers are used in digital substations. In this paper, the mathematical model of the electronic transformer is analyzed firstly, and its circuit model is given. According to the difference of working characteristics between voltage transformer and current transformer, the circuit model of voltage type electronic transformer and current type electronic transformer is given respectively. By analyzing their broadband transmission characteristics, the accuracy of the model is verified, and their lightning analysis models are obtained.

  6. Piezoelectric Transformer Characterization and Application of Electronic Ballast

    OpenAIRE

    Lin, Ray-Lee

    2001-01-01

    The characterization and modeling of piezoelectric transformers are studied and developed for use in electronic ballasts. By replacing conventional L-C resonant tanks with piezoelectric transformers, inductor-less piezoelectric transformer electronic ballasts have been developed for use in fluorescent lamps. The piezoelectric transformer is a combination of piezoelectric actuators as the primary side and piezoelectric transducers as the secondary side, both of which work in longitudinal o...

  7. Foundation: Transforming data bases into knowledge bases

    Science.gov (United States)

    Purves, R. B.; Carnes, James R.; Cutts, Dannie E.

    1987-01-01

    One approach to transforming information stored in relational data bases into knowledge based representations and back again is described. This system, called Foundation, allows knowledge bases to take advantage of vast amounts of pre-existing data. A benefit of this approach is inspection, and even population, of data bases through an intelligent knowledge-based front-end.

  8. MEMS based digital transform spectrometers

    Science.gov (United States)

    Geller, Yariv; Ramani, Mouli

    2005-09-01

    Earlier this year, a new breed of Spectrometers based on Micro-Electro-Mechanical-System (MEMS) engines has been introduced to the commercial market. The use of these engines combined with transform mathematics, produces powerful spectrometers at unprecedented low cost in various spectral regions.

  9. Tolerance-Based Feature Transforms

    NARCIS (Netherlands)

    Reniers, Dennie; Telea, Alexandru

    2007-01-01

    Tolerance-based feature transforms (TFTs) assign to each pixel in an image not only the nearest feature pixels on the boundary (origins), but all origins from the minimum distance up to a user-defined tolerance. In this paper, we compare four simple-to-implement methods for computing TFTs on binary

  10. Software to manage transformers using intelligent electronic device

    Directory of Open Access Journals (Sweden)

    Marcio Zamboti Fortes

    2016-01-01

    Full Text Available Power companies usually answer the increase in power demand by building new generation facilities. Nevertheless, an efficient use of energy could reduce and delay the costs of investment in new power plants. This paper shows a software system to manage transformers and evaluate losses when they work with zero loads. This system contributes to reduce the waste of energy with some simple actions such as shutting off an unused transformer or reconnecting disabled equipment based on the customer’s demand. It uses real time measurements collected from Intelligent Electronic Devices as a base for software decisions. It also measures and reports the total power saving.

  11. Paper based electronics platform

    KAUST Repository

    Nassar, Joanna Mohammad; Sevilla, Galo Andres Torres; Hussain, Muhammad Mustafa

    2017-01-01

    A flexible and non-functionalized low cost paper-based electronic system platform fabricated from common paper, such as paper based sensors, and methods of producing paper based sensors, and methods of sensing using the paper based sensors

  12. Vibrational frame transformation for electron-molecule scattering

    International Nuclear Information System (INIS)

    Greene, C.H.; Jungen, C.

    1985-01-01

    The frame-transformation theory of electron interaction with a vibrating diatomic core is extended to allow for energy dependence of its parameters. The Born-Oppenheimer separation of electron and nuclear motion is preserved when the electron penetrates the molecular core. The extended theory reproduces the boomerang-model treatment of vibrational excitation in resonant e-N 2 collisions

  13. Energy Transformation in Molecular Electronic Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kasha, Michael

    1999-05-17

    This laboratory has developed many new ideas and methods in the electronic spectroscopy of molecules. This report covers the contract period 1993-1995. A number of the projects were completed in 1996, and those papers are included in the report. The DOE contract was terminated at the end of 1995 owing to a reorganizational change eliminating nationally the projects under the Office of Health and Environmental Research, U. S. Department of Energy.

  14. Energy transformation in molecular electronic systems

    International Nuclear Information System (INIS)

    Kasha, M.

    1985-01-01

    Our new optical pumping spectroscopy (steady state, and double-laser pulse) allows the production and study of the unstable rare tautomer in its ground and excited states, including picosecond dynamic studies. Molecules under study here included 7-azaindole (model for biological purines), 3-hydroxyflavone (model for plant flavones), lumichrome, and other heterocyclics. New detailed molecular mechanisms for proton transfer are derived, especially with catalytic assisting molecules. A new proton-transfer laser of extraordinary efficiency has become a side dividend, possibly worth of industrial development. The excited and highly reactive singlet molecular oxygen species 1 Δ/sub g/) has proven to be ubiquitous in chemical peroxide systems and in physically excited sensitizer-oxygen systems. Hyperbaric oxygen mechanisms in biology probably involve singlet oxygen. We have undertaken a spectroscopic study of tris - dibenzoylmethane chelates of Al, Gd, Eu, and Yb trivalent ions. These chelates offer a variety of electronic behaviors, from Z-effects on π-electron spin-orbital coupling (Al, Gd) to Weissman intramolecular energy transfer to 4f mestable levels (Eu, Gd). Elegant new spectroscopic resolution at 77K permits separation of tautomeric, parasitic self-absorption, dissociation, and cage effects to be resolved. 18 refs., 4 figs

  15. Model Validation in Ontology Based Transformations

    Directory of Open Access Journals (Sweden)

    Jesús M. Almendros-Jiménez

    2012-10-01

    Full Text Available Model Driven Engineering (MDE is an emerging approach of software engineering. MDE emphasizes the construction of models from which the implementation should be derived by applying model transformations. The Ontology Definition Meta-model (ODM has been proposed as a profile for UML models of the Web Ontology Language (OWL. In this context, transformations of UML models can be mapped into ODM/OWL transformations. On the other hand, model validation is a crucial task in model transformation. Meta-modeling permits to give a syntactic structure to source and target models. However, semantic requirements have to be imposed on source and target models. A given transformation will be sound when source and target models fulfill the syntactic and semantic requirements. In this paper, we present an approach for model validation in ODM based transformations. Adopting a logic programming based transformational approach we will show how it is possible to transform and validate models. Properties to be validated range from structural and semantic requirements of models (pre and post conditions to properties of the transformation (invariants. The approach has been applied to a well-known example of model transformation: the Entity-Relationship (ER to Relational Model (RM transformation.

  16. Comprehensive Power Losses Model for Electronic Power Transformer

    DEFF Research Database (Denmark)

    Yue, Quanyou; Li, Canbing; Cao, Yijia

    2018-01-01

    and considering the impact of the non-unity power factor and the three-phase unbalanced current, the overall power losses in the distribution network when using the EPT to replace the conventional transformer is analyzed, and the conditions in which the application of the EPT can cause less power losses...... reduced power losses in the distribution network require a comprehensive consideration when comparing the power losses of theEPT and conventional transformer. In this paper, a comprehensive power losses analysis model for the EPT in distribution networks is proposed. By analyzing the EPT self-losses......The electronic power transformer (EPT) has highe rpower losses than the conventional transformer. However, the EPT can correct the power factor, compensate the unbalanced current and reduce the line power losses in the distribution network.Therefore, the higher losses of the EPT and the consequent...

  17. Comprehensive Power Losses Model for Electronic Power Transformer

    DEFF Research Database (Denmark)

    Yue, Quanyou; Li, Canbing; Cao, Yijia

    2018-01-01

    The electronic power transformer (EPT) has highe rpower losses than the conventional transformer. However, the EPT can correct the power factor, compensate the unbalanced current and reduce the line power losses in the distribution network.Therefore, the higher losses of the EPT and the consequent...... reduced power losses in the distribution network require a comprehensive consideration when comparing the power losses of theEPT and conventional transformer. In this paper, a comprehensive power losses analysis model for the EPT in distribution networks is proposed. By analyzing the EPT self......-losses and considering the impact of the non-unity power factor and the three-phase unbalanced current, the overall power losses in the distribution network when using the EPT to replace the conventional transformer is analyzed, and the conditions in which the application of the EPT can cause less power losses...

  18. Ontology Based Model Transformation Infrastructure

    NARCIS (Netherlands)

    Göknil, Arda; Topaloglu, N.Y.

    2005-01-01

    Using MDA in ontology development has been investigated in several works recently. The mappings and transformations between the UML constructs and the OWL elements to develop ontologies are the main concern of these research projects. We propose another approach in order to achieve the collaboration

  19. Electronic basis of hardness and phase transformations (covalent crystals)

    International Nuclear Information System (INIS)

    Gilman, J J

    2008-01-01

    Several electronic parameters measure the stabilities of covalent crystals, including minimum energy band-gap densities, inverse polarizabilities, plasma frequencies, transverse vibrational frequencies and elastic shear moduli. Convenient is the band-gap density (energy/volume; called the 'bond modulus'). For a given bonding type, the indentation hardness is proportional to the bond modulus. Examples are the group IV elements, III-V compounds; and II-VI compounds. The motion of dislocation kinks requires the excitation of bonding electrons into anti-bonding states. The bond modulus measures this together with the work done by the applied stress when a kink moves. In addition to hardness, the bond modulus measures the compressive strain (pressure) needed to transform an ambient structure into a more dense structure. Activation of such transformations also requires the excitation of bonding electrons into anti-bonding states together with the work done by the compressive stress

  20. Implementation of Transformer Protection by Intelligent Electronic Device for Different Faults

    OpenAIRE

    Y V Aruna, Beena S

    2015-01-01

    Protection of power system equipments was traditionally done by using electromagnetic relay, static relays, and numerical relays. At present the microprocessor based relays are replacing the old Electromagnetic relays because of their high level accuracy and fast operation. RET670(Transformer protection relay ), an IED (INTELLIGENT ELECTRONIC DEVICE) provides fast and selective protection, monitoring, and control of all types of transformer. The configured IED is tested under diff...

  1. DVD Based Electronic Pulser

    International Nuclear Information System (INIS)

    Morris, Scott J.; Pratt, Rick M.; Hughes, Michael A.; Kouzes, Richard T.; Pitts, W K.; Robinson, Eric E.

    2005-01-01

    This paper describes the design, construction, and testing of a DVD based electronic pulser system (DVDEPS). Such a device is used to generate pulse streams for simulation of both gamma and neutron detector systems. The DVDEPS reproduces a random pulse stream of a full HPGe spectrum as well as a digital pulse stream representing the output of a neutron multiplicity detector. The exchangeable DVD media contains over an hour of data for both detector systems and can contain an arbitrary gamma spectrum and neutron pulse stream. The data is written to the DVD using a desktop computer program from either actual or simulated spectra. The targeted use of the DVDEPS is authentication or validation of monitoring equipment for non-proliferation purposes, but it is also of general use whenever a complex data stream is required. The DVD based pulser combines the storage capacity and simplicity of DVD technology with commonly available electronic components to build a relatively inexpensive yet highly capable testing instrument

  2. Transformation language integration based on profiles and higher order transformations

    NARCIS (Netherlands)

    Van Gorp, P.M.E.; Keller, A.; Janssens, D.; Gaševic, D.; Lämmel, R.; Van Wyk, Eric

    2009-01-01

    For about two decades, researchers have been constructing tools for applying graph transformations on large model transformation case studies. Instead of incrementally extending a common core, these competitive tool builders have repeatedly reconstructed mechanisms that were already supported by

  3. Paper based electronics platform

    KAUST Repository

    Nassar, Joanna Mohammad

    2017-07-20

    A flexible and non-functionalized low cost paper-based electronic system platform fabricated from common paper, such as paper based sensors, and methods of producing paper based sensors, and methods of sensing using the paper based sensors are provided. A method of producing a paper based sensor can include the steps of: a) providing a conventional paper product to serve as a substrate for the sensor or as an active material for the sensor or both, the paper product not further treated or functionalized; and b) applying a sensing element to the paper substrate, the sensing element selected from the group consisting of a conductive material, the conductive material providing contacts and interconnects, sensitive material film that exhibits sensitivity to pH levels, a compressible and/or porous material disposed between a pair of opposed conductive elements, or a combination of two of more said sensing elements. The method of sensing can further include measuring, using the sensing element, a change in resistance, a change in voltage, a change in current, a change in capacitance, or a combination of any two or more thereof.

  4. Complete chemical transformation of a molecular film by subexcitation electrons (<3 eV).

    Science.gov (United States)

    Balog, Richard; Illenberger, Eugen

    2003-11-21

    The potential of slow electrons to act as a soft tool to control a chemical reaction in the condensed phase is demonstrated. By setting the energy of a well defined electron beam to values below 3 eV, the surface of a thin film of 1,2-C(2)F(4)C(l2) molecules can completely be transformed into molecular chlorine (and by-products, possibly perfluorinated polymers). At higher energies (>6 eV) some equilibrium state between product and educt composition can be achieved, however, accompanied by a gradual overall degradation of the film. The effect of complete transformation is based on both the selectivity and particular energy dependence of the initial step of the reaction which is dissociative electron attachment to C(2)F(4)C(l2), but also the fact that the initial molecule is efficiently decomposed by subexcitation electrons while the product C(l2) is virtually unaffected.

  5. Multilayer modal actuator-based piezoelectric transformers.

    Science.gov (United States)

    Huang, Yao-Tien; Wu, Wen-Jong; Wang, Yen-Chieh; Lee, Chih-Kung

    2007-02-01

    An innovative, multilayer piezoelectric transformer equipped with a full modal filtering input electrode is reported herein. This modal-shaped electrode, based on the orthogonal property of structural vibration modes, is characterized by full modal filtering to ensure that only the desired vibration mode is excited during operation. The newly developed piezoelectric transformer is comprised of three layers: a multilayered input layer, an insulation layer, and a single output layer. The electrode shape of the input layer is derived from its structural vibration modal shape, which takes advantage of the orthogonal property of the vibration modes to achieve a full modal filtering effect. The insulation layer possesses two functions: first, to couple the mechanical vibration energy between the input and output, and second, to provide electrical insulation between the two layers. To meet the two functions, a low temperature, co-fired ceramic (LTCC) was used to provide the high mechanical rigidity and high electrical insulation. It can be shown that this newly developed piezoelectric transformer has the advantage of possessing a more efficient energy transfer and a wider optimal working frequency range when compared to traditional piezoelectric transformers. A multilayer piezoelectric, transformer-based inverter applicable for use in LCD monitors or portable displays is presented as well.

  6. Module Ten: Transformers; Basic Electricity and Electronics Individualized Learning System.

    Science.gov (United States)

    Bureau of Naval Personnel, Washington, DC.

    The module introduces a very important electrical device, the transformer. The module is divided into six lessons: transformer construction, transformer theory and operation, turns and voltage ratios, power and current, transformer efficiency, and semiconductor rectifiers. Each lesson consists of an overview, a list of study resources, lesson…

  7. Madrasah Culture Based Transformational Leadership Model

    Directory of Open Access Journals (Sweden)

    Nur Khoiri

    2016-10-01

    Full Text Available Leadership is the ability to influence, direct behavior, and have a particular expertise in the field of the group who want to achieve the goals. A dynamic organization requires transformational leadership model. A school principal as a leader at school aims to actualize good learning leadership. Leadership learning focuses on learning which components include curriculum, teaching and learning process, assessment, teacher assessment and development, good service in learning, and developing a learning community in schools based on organizational culture as value, assumption, belief evolved from the roots of member thought of the organization and believed by all members of the organization and implemented in everyday life that could give meaning Keywords: leadership, transformational leadership, headmaster, instructional leadership, organizational culture.

  8. Pedestrian detection based on redundant wavelet transform

    Science.gov (United States)

    Huang, Lin; Ji, Liping; Hu, Ping; Yang, Tiejun

    2016-10-01

    Intelligent video surveillance is to analysis video or image sequences captured by a fixed or mobile surveillance camera, including moving object detection, segmentation and recognition. By using it, we can be notified immediately in an abnormal situation. Pedestrian detection plays an important role in an intelligent video surveillance system, and it is also a key technology in the field of intelligent vehicle. So pedestrian detection has very vital significance in traffic management optimization, security early warn and abnormal behavior detection. Generally, pedestrian detection can be summarized as: first to estimate moving areas; then to extract features of region of interest; finally to classify using a classifier. Redundant wavelet transform (RWT) overcomes the deficiency of shift variant of discrete wavelet transform, and it has better performance in motion estimation when compared to discrete wavelet transform. Addressing the problem of the detection of multi-pedestrian with different speed, we present an algorithm of pedestrian detection based on motion estimation using RWT, combining histogram of oriented gradients (HOG) and support vector machine (SVM). Firstly, three intensities of movement (IoM) are estimated using RWT and the corresponding areas are segmented. According to the different IoM, a region proposal (RP) is generated. Then, the features of a RP is extracted using HOG. Finally, the features are fed into a SVM trained by pedestrian databases and the final detection results are gained. Experiments show that the proposed algorithm can detect pedestrians accurately and efficiently.

  9. Observations of cellular transformation products in nickel-base superalloys

    International Nuclear Information System (INIS)

    Barlow, C.Y.; Ralph, B.

    1979-01-01

    Transmission electron microscopy has been used to identify the products in cellularly transformed regions of alloys based on the Nimonic 80 A composition. The commercial alloy is shown to undergo a small degree of cellular transformation even after conventional heat treatments, while recrystallization is found to increase the incidence of this reaction type. Low carbon versions of this alloy demonstrate cellular precipitation over a wider range of heat treatments. It is shown that the cellular reaction may take place in these alloys under a variety of different conditions and with a range of driving forces. Reasons for this unexpected behaviour are offeredm as is a suggestion as to why the cellular reaction occurs on a local scale. (author)

  10. Motion Analysis Based on Invertible Rapid Transform

    Directory of Open Access Journals (Sweden)

    J. Turan

    1999-06-01

    Full Text Available This paper presents the results of a study on the use of invertible rapid transform (IRT for the motion estimation in a sequence of images. Motion estimation algorithms based on the analysis of the matrix of states (produced in the IRT calculation are described. The new method was used experimentally to estimate crowd and traffic motion from the image data sequences captured at railway stations and at high ways in large cities. The motion vectors may be used to devise a polar plot (showing velocity magnitude and direction for moving objects where the dominant motion tendency can be seen. The experimental results of comparison of the new motion estimation methods with other well known block matching methods (full search, 2D-log, method based on conventional (cross correlation (CC function or phase correlation (PC function for application of crowd motion estimation are also presented.

  11. Improving the cooling performance of electrical distribution transformer using transformer oil – Based MEPCM suspension

    OpenAIRE

    Mushtaq Ismael Hasan

    2017-01-01

    In this paper the electrical distribution transformer has been studied numerically and the effect of outside temperature on its cooling performance has been investigated. The temperature range studied covers the hot climate regions. 250 KVA distribution transformer is chosen as a study model. A novel cooling fluid is proposed to improve the cooling performance of this transformer, transformer oil-based microencapsulated phase change materials suspension is used with volume concentration (5–25...

  12. Transformational electronics: a powerful way to revolutionize our information world

    Science.gov (United States)

    Rojas, Jhonathan P.; Torres Sevilla, Galo A.; Ghoneim, Mohamed T.; Hussain, Aftab M.; Ahmed, Sally M.; Nassar, Joanna M.; Bahabry, Rabab R.; Nour, Maha; Kutbee, Arwa T.; Byas, Ernesto; Al-Saif, Bidoor; Alamri, Amal M.; Hussain, Muhammad M.

    2014-06-01

    With the emergence of cloud computation, we are facing the rising waves of big data. It is our time to leverage such opportunity by increasing data usage both by man and machine. We need ultra-mobile computation with high data processing speed, ultra-large memory, energy efficiency and multi-functionality. Additionally, we have to deploy energy-efficient multi-functional 3D ICs for robust cyber-physical system establishment. To achieve such lofty goals we have to mimic human brain, which is inarguably the world's most powerful and energy efficient computer. Brain's cortex has folded architecture to increase surface area in an ultra-compact space to contain its neuron and synapses. Therefore, it is imperative to overcome two integration challenges: (i) finding out a low-cost 3D IC fabrication process and (ii) foldable substrates creation with ultra-large-scale-integration of high performance energy efficient electronics. Hence, we show a low-cost generic batch process based on trench-protect-peel-recycle to fabricate rigid and flexible 3D ICs as well as high performance flexible electronics. As of today we have made every single component to make a fully flexible computer including non-planar state-of-the-art FinFETs. Additionally we have demonstrated various solid-state memory, movable MEMS devices, energy harvesting and storage components. To show the versatility of our process, we have extended our process towards other inorganic semiconductor substrates such as silicon germanium and III-V materials. Finally, we report first ever fully flexible programmable silicon based microprocessor towards foldable brain computation and wirelessly programmable stretchable and flexible thermal patch for pain management for smart bionics.

  13. Transformational electronics: a powerful way to revolutionize our information world

    KAUST Repository

    Rojas, Jhonathan Prieto

    2014-06-04

    With the emergence of cloud computation, we are facing the rising waves of big data. It is our time to leverage such opportunity by increasing data usage both by man and machine. We need ultra-mobile computation with high data processing speed, ultra-large memory, energy efficiency and multi-functionality. Additionally, we have to deploy energy-efficient multi-functional 3D ICs for robust cyber-physical system establishment. To achieve such lofty goals we have to mimic human brain, which is inarguably the world’s most powerful and energy efficient computer. Brain’s cortex has folded architecture to increase surface area in an ultra-compact space to contain its neuron and synapses. Therefore, it is imperative to overcome two integration challenges: (i) finding out a low-cost 3D IC fabrication process and (ii) foldable substrates creation with ultra-large-scale-integration of high performance energy efficient electronics. Hence, we show a low-cost generic batch process based on trench-protect-peel-recycle to fabricate rigid and flexible 3D ICs as well as high performance flexible electronics. As of today we have made every single component to make a fully flexible computer including non-planar state-of-the-art FinFETs. Additionally we have demonstrated various solid-state memory, movable MEMS devices, energy harvesting and storage components. To show the versatility of our process, we have extended our process towards other inorganic semiconductor substrates such as silicon germanium and III-V materials. Finally, we report first ever fully flexible programmable silicon based microprocessor towards foldable brain computation and wirelessly programmable stretchable and flexible thermal patch for pain management for smart bionics. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  14. Transforming health care the financial impact of technology, electronic tools and data mining

    CERN Document Server

    Fasano, Phil

    2013-01-01

    The future of healthcare technologies, and what they mean for investors and entrepreneurs The healthcare technology revolution is just around the corner. And when it arrives, it will change and enrich our lives in ways we can only begin to imagine. Doctors will perform blood pressure readings via video chat and nutritionists will analyze diet based on photos taken with cellphone cameras. Transforming Health Care combines healthcare, technology, and finance in an innovative new way that explains the future of healthcare and its effects on patient care, exploring the emergence of electronic tools that will transform the medical industry. Explaining how technology, not politics, will lead the future of the healthcare revolution, author and healthcare technology expert Phil Fasano presents real-life examples that show how the next generation of medical breakthroughs will come from the instant exchange of information across the world Explores how new technologies will radically change the future of healthcare by m...

  15. Model based analysis of piezoelectric transformers.

    Science.gov (United States)

    Hemsel, T; Priya, S

    2006-12-22

    Piezoelectric transformers are increasingly getting popular in the electrical devices owing to several advantages such as small size, high efficiency, no electromagnetic noise and non-flammable. In addition to the conventional applications such as ballast for back light inverter in notebook computers, camera flash, and fuel ignition several new applications have emerged such as AC/DC converter, battery charger and automobile lighting. These new applications demand high power density and wide range of voltage gain. Currently, the transformer power density is limited to 40 W/cm(3) obtained at low voltage gain. The purpose of this study was to investigate a transformer design that has the potential of providing higher power density and wider range of voltage gain. The new transformer design utilizes radial mode both at the input and output port and has the unidirectional polarization in the ceramics. This design was found to provide 30 W power with an efficiency of 98% and 30 degrees C temperature rise from the room temperature. An electro-mechanical equivalent circuit model was developed to describe the characteristics of the piezoelectric transformer. The model was found to successfully predict the characteristics of the transformer. Excellent matching was found between the computed and experimental results. The results of this study will allow to deterministically design unipoled piezoelectric transformers with specified performance. It is expected that in near future the unipoled transformer will gain significant importance in various electrical components.

  16. Research on Digital Output Verification Technology of Electronic DC Current Transformer

    Science.gov (United States)

    Chen, Yuanjie; Wang, Bin; Hu, Haoliang; Xiong, Qianzhu; Yang, Chunyan

    2017-05-01

    Aiming at the error of calibration system when conducting field calibration by electronic DC current transformer’s digital calibration system, an electronic DC current transformer’s digital calibration system based on protocol conversion is proposed and researched. Data frames outputted from merging unit are collected and converted by the system, the digital synchronization is realized by using the synchronous clock device to trigger the second pulse, and it is verified by the virtual instrument design software. The field calibration is conducted to some converter station digital dc current transformer under the rated current of 500A by using the calibration system. By calibrating and analyzing errors, the error is less than 0.075% when tested current is more than 40% of the rated current. According the standard in literature[1], performance of the calibration system is perfect, measured results perfectly meet the requirements of design, and the calibration system has great practical application value.

  17. Description of the electron-hydrogen collision by the Coulomb Fourier transform method

    International Nuclear Information System (INIS)

    Levin, S.B.

    2005-01-01

    A recently developed Coulomb Fourier Transform method is applied to the system containing one heavy ion and two electrons. The transformed Hamiltonian is described with a controlled accuracy in an effective finite basis set as a finite dimensional operator matrix. The kernels of interaction are formulated in terms of the so called Nordsieck integrals

  18. Relativistic electron beam source with an air-core step-up transformer

    International Nuclear Information System (INIS)

    Mohri, Akihiro; Ikuta, Kazunari; Masuzaki, Masaru; Tsuzuki, Tetsuya; Fujiwaka, Setsuya.

    1975-04-01

    An air-core step-up transformer with a high coupling factor has been developed to generate a high voltage pulse for charging the pulse forming line of a relativistic electron beam source. A beam source using the transformer was constructed and well operated for the beam injection into a toroidal system. (auth.)

  19. A direct method to transform between expansions in the configuration state function and Slater determinant bases

    International Nuclear Information System (INIS)

    Olsen, Jeppe

    2014-01-01

    A novel algorithm is introduced for the transformation of wave functions between the bases of Slater determinants (SD) and configuration state functions (CSF) in the genealogical coupling scheme. By modifying the expansion coefficients as each electron is spin-coupled, rather than performing a single many-electron transformation, the large transformation matrix that plagues previous approaches is avoided and the required number of operations is drastically reduced. As an example of the efficiency of the algorithm, the transformation for a configuration with 30 unpaired electrons and singlet spin is discussed. For this case, the 10 × 10 6 coefficients in the CSF basis is obtained from the 150 × 10 6 coefficients in the SD basis in 1 min, which should be compared with the seven years that the previously employed method is estimated to require

  20. Competition: A Means to Transform the Defense Industrial Base

    National Research Council Canada - National Science Library

    Hansen, Richard

    2003-01-01

    .... The defense acquisition process and its industrial base comprise a significant economic institution in need of transformation to ensure that research, development, and acquisition efforts remain...

  1. Investigation of the martensitic phase transformations in CoFe single crystals using high-resolution transmission electron microscopy

    International Nuclear Information System (INIS)

    Waitz, T.

    1999-06-01

    In CoFe crystals containing 0.85, 1.5, 5.75 and 6.0at.% Fe the thermally induced martensitic phase transformations between the close packed lattices face centered cubic (fcc), double hexagonal close packed (dhcp) and hexagonal close packed (hcp) were studied. Transmission electron microscopy methods were applied including in-situ experiments; both high-resolution transmission electron microscopy (HRTEM) images and lattice fringe images were used to analyze the transformations at an atomic scale. Based on the results of both the transformations in the bulk and the in-situ transformations it is concluded that the phase transitions occur by the formation of lamellae on the close packed habit planes. The lamellae have a minimum thickness of 10 to 15 close packed planes; therefore transformation models that are based on random overlap of stacking faults can be excluded. The glissile transformation fronts of the lamellae contain transformation dislocations (partials) that are correlated on an atomic scale. In the HRTEM images partials that are only about 0.2 nm apart were resolved and analyzed in detail by circuits that are similar to Burgers circuits. Two attracting partials on adjacent close packed planes are the structural units of the transformation fronts; they are dipoles and paired partials (with a total Burgers vector of a single partial) in the case of the transformations hcp dhcp and fcc dhcp, respectively. Different arrangements of the partials at the transformation fronts lead to two different modes A and B of the phase transition. These two modes seem to be competitive processes that can be favored by different parameters of the material (as chemical composition and microstructure). Partials of mode A transformations have the same Burgers vectors; therefore the partials repel each other causing long range internal stresses and large transformation shear strains that can lead to a surface relief. Whereas, partials of mode B transformations have different

  2. Using the transformer oil-based nanofluid for cooling of power distribution transformer

    OpenAIRE

    Mushtaq Ismael Hasan

    2017-01-01

    Thermal behavior of electrical distribution transformer has been numerically studied with the effect of surrounding air temperature. 250 KVA distribution transformer is chosen as a study model and studied in temperature range cover the weather conditions of hot places. Transformer oil-based nanofluids were used as a cooling medium instead of pure transformer oil. Four types of solid particles (Cu, Al2O3, TiO2 and SiC) were used to compose nanofluids with volume fractions (1%, 3%, 5%, 7%, and ...

  3. Fourier transform based scalable image quality measure.

    Science.gov (United States)

    Narwaria, Manish; Lin, Weisi; McLoughlin, Ian; Emmanuel, Sabu; Chia, Liang-Tien

    2012-08-01

    We present a new image quality assessment (IQA) algorithm based on the phase and magnitude of the 2D (twodimensional) Discrete Fourier Transform (DFT). The basic idea is to compare the phase and magnitude of the reference and distorted images to compute the quality score. However, it is well known that the Human Visual Systems (HVSs) sensitivity to different frequency components is not the same. We accommodate this fact via a simple yet effective strategy of nonuniform binning of the frequency components. This process also leads to reduced space representation of the image thereby enabling the reduced-reference (RR) prospects of the proposed scheme. We employ linear regression to integrate the effects of the changes in phase and magnitude. In this way, the required weights are determined via proper training and hence more convincing and effective. Lastly, using the fact that phase usually conveys more information than magnitude, we use only the phase for RR quality assessment. This provides the crucial advantage of further reduction in the required amount of reference image information. The proposed method is therefore further scalable for RR scenarios. We report extensive experimental results using a total of 9 publicly available databases: 7 image (with a total of 3832 distorted images with diverse distortions) and 2 video databases (totally 228 distorted videos). These show that the proposed method is overall better than several of the existing fullreference (FR) algorithms and two RR algorithms. Additionally, there is a graceful degradation in prediction performance as the amount of reference image information is reduced thereby confirming its scalability prospects. To enable comparisons and future study, a Matlab implementation of the proposed algorithm is available at http://www.ntu.edu.sg/home/wslin/reduced_phase.rar.

  4. Design of space-type electronic power transformers

    Science.gov (United States)

    Ahearn, J. F.; Lagadinos, J. C.

    1977-01-01

    Both open and encapsulated varieties of high reliability, low weight, and high efficiency moderate and high voltage transformers were investigated to determine the advantages and limitations of their construction in the ranges of power and voltage required for operation in the hard vacuum environment of space. Topics covered include: (1) selection of the core material; (2) preliminary calculation of core dimensions; (3) selection of insulating materials including magnet wire insulation, coil forms, and layer and interwinding insulation; (4) coil design; (5) calculation of copper losses, core losses and efficiency; (6) calculation of temperature rise; and (7) optimization of design with changes in core selection or coil design as required to meet specifications.

  5. Carbon Nanotube Based Molecular Electronics

    Science.gov (United States)

    Srivastava, Deepak; Saini, Subhash; Menon, Madhu

    1998-01-01

    Carbon nanotubes and the nanotube heterojunctions have recently emerged as excellent candidates for nanoscale molecular electronic device components. Experimental measurements on the conductivity, rectifying behavior and conductivity-chirality correlation have also been made. While quasi-one dimensional simple heterojunctions between nanotubes with different electronic behavior can be generated by introduction of a pair of heptagon-pentagon defects in an otherwise all hexagon graphene sheet. Other complex 3- and 4-point junctions may require other mechanisms. Structural stability as well as local electronic density of states of various nanotube junctions are investigated using a generalized tight-binding molecular dynamics (GDBMD) scheme that incorporates non-orthogonality of the orbitals. The junctions investigated include straight and small angle heterojunctions of various chiralities and diameters; as well as more complex 'T' and 'Y' junctions which do not always obey the usual pentagon-heptagon pair rule. The study of local density of states (LDOS) reveal many interesting features, most prominent among them being the defect-induced states in the gap. The proposed three and four pointjunctions are one of the smallest possible tunnel junctions made entirely of carbon atoms. Furthermore the electronic behavior of the nanotube based device components can be taylored by doping with group III-V elements such as B and N, and BN nanotubes as a wide band gap semiconductor has also been realized in experiments. Structural properties of heteroatomic nanotubes comprising C, B and N will be discussed.

  6. Transformative leadership based on nursing science.

    Science.gov (United States)

    Clarke, Pamela N; Cody, William; Cowling, Richard

    2014-04-01

    The dialogue for this column is a summary of a dialogue among two preeminent nursing scholars and myself that took place "live" at the 40th Meeting of the American Academy of Nursing, focused on transforming healthcare. The dialogue was recorded and transcribed verbatim. In editing the dialogue I tried to leave it conversational which was the nature of the interaction. The paper that follows reflects the thinking of two executive nurse leaders who use different nursing frameworks as the basis for their practice. Translation of their practice models to leadership is presented as a natural transition to transformation.

  7. Instrument electronic transformers for medium voltage systems; Transformadores eletronicos de instrumentos para sistemas de media tensao

    Energy Technology Data Exchange (ETDEWEB)

    Javora, Radek; Stefanka, Martin; Mahonen, Pentti; Niemi, Tapio; Rintamaki, Olli [ABB, Helsinki (Finland); ABB, Prague (Czech Republic)

    2010-02-15

    This paper compares the conventional technologies and the electronic of instrument transformers, and highlights the advantages, discoveries and principles of electronic models. Such equipment are essentially indicated for using with as micro processed relays at the substations, and also projected for connection to the IEDs, and the future digital communication (author)

  8. A pulsed electron gun for the Plane Wave Transformer Linac

    Science.gov (United States)

    Mahadevan, S.; Gandhi, M. L.; Nandedkar, R. V.

    2003-01-01

    A pulsed diode electron gun delivering 500 mA current at 40 kV is described. The gun geometry is optimized using the Electron Trajectory Program EGUN at higher scaling factors by choosing the closest converging starting surface. The effect of an annular gap between cathode and focusing electrode on beam behaviour is compensated by using a suitable focusing electrode. The estimated perveance is 0.065 μperv and the normalized emittance is within 5 π mm mrad. The variation in current density at the cathode has been limited to within 10% across the face of the cathode. Salient features of the pulsed power supply and an insight of its interconnection with the gun are presented. The current measured at the Faraday cup is in agreement with the designed perveance.

  9. A pulsed electron gun for the Plane Wave Transformer Linac

    Energy Technology Data Exchange (ETDEWEB)

    Mahadevan, S. E-mail: maharaja@cat.ernet.in; Gandhi, M.L. E-mail: mlg@cat.ernet.in; Nandedkar, R.V. E-mail: nrv@cat.ernet.in

    2003-01-01

    A pulsed diode electron gun delivering 500 mA current at 40 kV is described. The gun geometry is optimized using the Electron Trajectory Program EGUN at higher scaling factors by choosing the closest converging starting surface. The effect of an annular gap between cathode and focusing electrode on beam behaviour is compensated by using a suitable focusing electrode. The estimated perveance is 0.065 {mu}perv and the normalized emittance is within 5{pi} mm mrad. The variation in current density at the cathode has been limited to within 10% across the face of the cathode. Salient features of the pulsed power supply and an insight of its interconnection with the gun are presented. The current measured at the Faraday cup is in agreement with the designed perveance.

  10. A pulsed electron gun for the Plane Wave Transformer Linac

    CERN Document Server

    Mahadevan, S; Nandedkar, R V

    2003-01-01

    A pulsed diode electron gun delivering 500 mA current at 40 kV is described. The gun geometry is optimized using the Electron Trajectory Program EGUN at higher scaling factors by choosing the closest converging starting surface. The effect of an annular gap between cathode and focusing electrode on beam behaviour is compensated by using a suitable focusing electrode. The estimated perveance is 0.065 mu perv and the normalized emittance is within 5 pi mm mrad. The variation in current density at the cathode has been limited to within 10% across the face of the cathode. Salient features of the pulsed power supply and an insight of its interconnection with the gun are presented. The current measured at the Faraday cup is in agreement with the designed perveance.

  11. A pulsed electron gun for the Plane Wave Transformer Linac

    International Nuclear Information System (INIS)

    Mahadevan, S.; Gandhi, M.L.; Nandedkar, R.V.

    2003-01-01

    A pulsed diode electron gun delivering 500 mA current at 40 kV is described. The gun geometry is optimized using the Electron Trajectory Program EGUN at higher scaling factors by choosing the closest converging starting surface. The effect of an annular gap between cathode and focusing electrode on beam behaviour is compensated by using a suitable focusing electrode. The estimated perveance is 0.065 μperv and the normalized emittance is within 5π mm mrad. The variation in current density at the cathode has been limited to within 10% across the face of the cathode. Salient features of the pulsed power supply and an insight of its interconnection with the gun are presented. The current measured at the Faraday cup is in agreement with the designed perveance

  12. Surface Design Based on Discrete Conformal Transformations

    Science.gov (United States)

    Duque, Carlos; Santangelo, Christian; Vouga, Etienne

    Conformal transformations are angle-preserving maps from one domain to another. Although angles are preserved, the lengths between arbitrary points are not generally conserved. As a consequence there is always a given amount of distortion associated to any conformal map. Different uses of such transformations can be found in various fields, but have been used by us to program non-uniformly swellable gel sheets to buckle into prescribed three dimensional shapes. In this work we apply circle packings as a kind of discrete conformal map in order to find conformal maps from the sphere to the plane that can be used as nearly uniform swelling patterns to program non-Euclidean sheets to buckle into spheres. We explore the possibility of tuning the area distortion to fit the experimental range of minimum and maximum swelling by modifying the boundary of the planar domain through the introduction of different cutting schemes.

  13. Madrasah Culture Based Transformational Leadership Model

    OpenAIRE

    Nur Khoiri

    2016-01-01

    Leadership is the ability to influence, direct behavior, and have a particular expertise in the field of the group who want to achieve the goals. A dynamic organization requires transformational leadership model. A school principal as a leader at school aims to actualize good learning leadership. Leadership learning focuses on learning which components include curriculum, teaching and learning process, assessment, teacher assessment and development, good service in learning, and developing a ...

  14. Improving the cooling performance of electrical distribution transformer using transformer oil – Based MEPCM suspension

    Directory of Open Access Journals (Sweden)

    Mushtaq Ismael Hasan

    2017-04-01

    Full Text Available In this paper the electrical distribution transformer has been studied numerically and the effect of outside temperature on its cooling performance has been investigated. The temperature range studied covers the hot climate regions. 250 KVA distribution transformer is chosen as a study model. A novel cooling fluid is proposed to improve the cooling performance of this transformer, transformer oil-based microencapsulated phase change materials suspension is used with volume concentration (5–25% as a cooling fluid instead of pure transformer oil. Paraffin wax is used as a phase change material to make the suspension, in addition to the ability of heat absorption due to melting, the paraffin wax considered as a good electrical insulator. Results obtained show that, using of MEPCM suspension instead of pure transformer oil lead to improve the cooling performance of transformer by reducing its temperature and as a consequence increasing its protection against the breakdown. The melting fraction increased with increasing outside temperature up to certain temperature after which the melting fraction reach maximum constant value (MF = 1 which indicate that, the choosing of PCM depend on the environment in which the transformer is used.

  15. Invariant object recognition based on the generalized discrete radon transform

    Science.gov (United States)

    Easley, Glenn R.; Colonna, Flavia

    2004-04-01

    We introduce a method for classifying objects based on special cases of the generalized discrete Radon transform. We adjust the transform and the corresponding ridgelet transform by means of circular shifting and a singular value decomposition (SVD) to obtain a translation, rotation and scaling invariant set of feature vectors. We then use a back-propagation neural network to classify the input feature vectors. We conclude with experimental results and compare these with other invariant recognition methods.

  16. Transformation of standardized clinical models based on OWL technologies: from CEM to OpenEHR archetypes.

    Science.gov (United States)

    Legaz-García, María del Carmen; Menárguez-Tortosa, Marcos; Fernández-Breis, Jesualdo Tomás; Chute, Christopher G; Tao, Cui

    2015-05-01

    The semantic interoperability of electronic healthcare records (EHRs) systems is a major challenge in the medical informatics area. International initiatives pursue the use of semantically interoperable clinical models, and ontologies have frequently been used in semantic interoperability efforts. The objective of this paper is to propose a generic, ontology-based, flexible approach for supporting the automatic transformation of clinical models, which is illustrated for the transformation of Clinical Element Models (CEMs) into openEHR archetypes. Our transformation method exploits the fact that the information models of the most relevant EHR specifications are available in the Web Ontology Language (OWL). The transformation approach is based on defining mappings between those ontological structures. We propose a way in which CEM entities can be transformed into openEHR by using transformation templates and OWL as common representation formalism. The transformation architecture exploits the reasoning and inferencing capabilities of OWL technologies. We have devised a generic, flexible approach for the transformation of clinical models, implemented for the unidirectional transformation from CEM to openEHR, a series of reusable transformation templates, a proof-of-concept implementation, and a set of openEHR archetypes that validate the methodological approach. We have been able to transform CEM into archetypes in an automatic, flexible, reusable transformation approach that could be extended to other clinical model specifications. We exploit the potential of OWL technologies for supporting the transformation process. We believe that our approach could be useful for international efforts in the area of semantic interoperability of EHR systems. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Design and performance of a Tesla transformer type relativistic electron beam generator

    International Nuclear Information System (INIS)

    Jain, K.K.; Chennareddy, D.; John, P.I.; Saxena, Y.C.

    1986-01-01

    A relativistic electron beam generator driven by an air core Tesla transformer is described. The Tesla transformer circuit analysis is outlined and computational results are presented for the case when the coaxial water line has finite resistance. The transformer has a coupling coefficient of 0.56 and a step-up ratio of 25. The Tesla transformer can provide 800 kV at the peak of the second half cycle of the secondary output voltage and has been tested up to 600 kV. A 100-200 keV, 15-20 kA electron beam having 150 ns pulse width has been obtained. The beam generator described is being used for the beam injection into a toroidal device BETA. (author). 20 refs. 9 figures

  18. Electronic Data Safes as an Infrastructure for Transformational Government? A Case Study

    OpenAIRE

    Pfister, Joachim; Schwabe, Gerhard

    2015-01-01

    Part 3: Services, Processes and Infrastructure; International audience; This article introduces and explores the potential of an active electronic data safe (AEDS) serving as an infrastructure to achieve transformational government. An AEDS connects individuals and organizations from the private and the public sector to exchange information items related to business processes following the user-managed access paradigm. To realize the transformational government’s vision of user-centricity, fu...

  19. Plate-shaped transformation products in zirconium-base alloys

    International Nuclear Information System (INIS)

    Banerjee, S.; Dey, G.K.; Srivastava, D.

    1997-01-01

    Plate-shaped products resulting from martensitic, diffusional, and mixed mode transformations in zirconium-base alloys are compared in the present study. These alloys are particularly suitable for the comparison in view of the fact that the lattice correspondence between the parent β (bcc) and the product α (hcp) or γ-hydride (fct) phases are remarkably similar for different types of transformations. Crystallographic features such as orientation relations, habit planes, and interface structures associated with these transformations have been compared, with a view toward examining whether the transformation mechanisms have characteristic imprints on these experimental observables

  20. Gear Fault Detection Based on Teager-Huang Transform

    Directory of Open Access Journals (Sweden)

    Hui Li

    2010-01-01

    Full Text Available Gear fault detection based on Empirical Mode Decomposition (EMD and Teager Kaiser Energy Operator (TKEO technique is presented. This novel method is named as Teager-Huang transform (THT. EMD can adaptively decompose the vibration signal into a series of zero mean Intrinsic Mode Functions (IMFs. TKEO can track the instantaneous amplitude and instantaneous frequency of the Intrinsic Mode Functions at any instant. The experimental results provide effective evidence that Teager-Huang transform has better resolution than that of Hilbert-Huang transform. The Teager-Huang transform can effectively diagnose the fault of the gear, thus providing a viable processing tool for gearbox defect detection and diagnosis.

  1. Watermarking on 3D mesh based on spherical wavelet transform.

    Science.gov (United States)

    Jin, Jian-Qiu; Dai, Min-Ya; Bao, Hu-Jun; Peng, Qun-Sheng

    2004-03-01

    In this paper we propose a robust watermarking algorithm for 3D mesh. The algorithm is based on spherical wavelet transform. Our basic idea is to decompose the original mesh into a series of details at different scales by using spherical wavelet transform; the watermark is then embedded into the different levels of details. The embedding process includes: global sphere parameterization, spherical uniform sampling, spherical wavelet forward transform, embedding watermark, spherical wavelet inverse transform, and at last resampling the mesh watermarked to recover the topological connectivity of the original model. Experiments showed that our algorithm can improve the capacity of the watermark and the robustness of watermarking against attacks.

  2. Active Power Measurement Based on Multiwavelet Transforms

    Directory of Open Access Journals (Sweden)

    Xiao-Bing Zhang

    2014-01-01

    Full Text Available This paper discusses a new method for calculating active power in the multiwavelet domain. When the voltage and current waveforms are analyzed using multiwavelet, the active power can be calculated by simply adding the products of the multiwavelet coefficients without having to reconstruct the signals back to the time domain first and then using the traditional integration. From the simulation result, we can see that the results using multiwavelet are better than the ones using wavelet and Fourier Transforms no matter which prefilter is used.

  3. The inertia system coordinate transformation based on the Lobachevsky function

    International Nuclear Information System (INIS)

    Fadeev, N.G.

    2001-01-01

    Based on the interpretation of the Lobachevsky function cosΠ(ρ/k) = thρ/k as the function which expresses the constant light velocity principle at k = c (k is the Lobachevsky constant, c is the light velocity), the inertia system coordinate transformation of two kinds (one of them known as Lorentz transformation) have been obtained

  4. Optimal Operation of Distribution Electronic Power Transformer Using Linear Quadratic Regulator Method

    Directory of Open Access Journals (Sweden)

    Mohammad Hosein Rezaei

    2011-10-01

    Full Text Available Transformers perform many functions such as voltage transformation, isolation and noise decoupling. They are indispensable components in electric power distribution system. However, at low frequencies (50 Hz, they are one of the heaviest and the most expensive equipment in an electrical distribution system. Nowadays, electronic power transformers are used instead of conventional power transformers that do voltage transformation and power delivery in power system by power electronic converter. In this paper, the structure of distribution electronic power transformer (DEPT are analized and then paid attention on the design of a linear-quadratic-regulator (LQR with integral action to improve dynamic performance of DEPT with voltage unbalance, voltage sags, voltage harmonics and voltage flicker. The presentation control strategy is simulated by MATLAB/SIMULINK. In addition, the results that are in terms of dc-link reference voltage, input and output voltages clearly show that a better dynamic performance can be achieved by using the LQR method when compared to other techniques.

  5. Low voltage driven dielectric electro active polymer actuator with integrated piezoelectric transformer based driver

    DEFF Research Database (Denmark)

    Andersen, Thomas; Rødgaard, Martin Schøler; Thomsen, Ole Cornelius

    2011-01-01

    actuators, a low voltage solution is developed by integrating the driver electronic into a 110 mm tall cylindrical coreless Push InLastor actuator. To decrease the size of the driver, a piezoelectric transformer (PT) based solution is utilized. The PT is essentially an improved Rosen type PT...

  6. Finite Countermodel Based Verification for Program Transformation (A Case Study

    Directory of Open Access Journals (Sweden)

    Alexei P. Lisitsa

    2015-12-01

    Full Text Available Both automatic program verification and program transformation are based on program analysis. In the past decade a number of approaches using various automatic general-purpose program transformation techniques (partial deduction, specialization, supercompilation for verification of unreachability properties of computing systems were introduced and demonstrated. On the other hand, the semantics based unfold-fold program transformation methods pose themselves diverse kinds of reachability tasks and try to solve them, aiming at improving the semantics tree of the program being transformed. That means some general-purpose verification methods may be used for strengthening program transformation techniques. This paper considers the question how finite countermodels for safety verification method might be used in Turchin's supercompilation method. We extract a number of supercompilation sub-algorithms trying to solve reachability problems and demonstrate use of an external countermodel finder for solving some of the problems.

  7. Catalytic Transformation of Ethylbenzene over Y-Zeolite-based Catalysts

    KAUST Repository

    Al-Khattaf, Sulaiman

    2008-01-01

    Catalytic transformation of ethylbenzene (EB) has been investigated over ultrastable Y (USY)-zeolite-based catalysts in a novel riser simulator at different operating conditions. The effect of reaction conditions on EB conversion is reported

  8. An improved Hough transform-based fingerprint alignment approach

    CSIR Research Space (South Africa)

    Mlambo, CS

    2014-11-01

    Full Text Available An improved Hough Transform based fingerprint alignment approach is presented, which improves computing time and memory usage with accurate alignment parameter (rotation and translation) results. This is achieved by studying the strengths...

  9. Multispectral image pansharpening based on the contourlet transform

    Energy Technology Data Exchange (ETDEWEB)

    Amro, Israa; Mateos, Javier, E-mail: iamro@correo.ugr.e, E-mail: jmd@decsai.ugr.e [Departamento de Ciencias de la Computacion e I.A., Universidad de Granada, 18071 Granada (Spain)

    2010-02-01

    Pansharpening is a technique that fuses the information of a low resolution multispectral image (MS) and a high resolution panchromatic image (PAN), usually remote sensing images, to provide a high resolution multispectral image. In the literature, this task has been addressed from different points of view being one of the most popular the wavelets based algorithms. Recently, the contourlet transform has been proposed. This transform combines the advantages of the wavelets transform with a more efficient directional information representation. In this paper we propose a new pansharpening method based on contourlets, compare with its wavelet counterpart and assess its performance numerically and visually.

  10. An Automated Energy Detection Algorithm Based on Morphological Filter Processing with a Modified Watershed Transform

    Science.gov (United States)

    2018-01-01

    ARL-TR-8270 ● JAN 2018 US Army Research Laboratory An Automated Energy Detection Algorithm Based on Morphological Filter...Automated Energy Detection Algorithm Based on Morphological Filter Processing with a Modified Watershed Transform by Kwok F Tom Sensors and Electron...1 October 2016–30 September 2017 4. TITLE AND SUBTITLE An Automated Energy Detection Algorithm Based on Morphological Filter Processing with a

  11. Transformer Temperature Measurment Using Optical Fiber Based Microbend Sensor

    Directory of Open Access Journals (Sweden)

    Deepika YADAV

    2007-10-01

    Full Text Available Breakdown of transformers proves to be very expensive and inconvenient because it takes a lot of time for their replacement. During breakdown the industry also incurs heavy losses because of stoppage in production line. A system for monitoring the temperature of transformers is required. Existing sensors cannot be used for monitoring the temperature of transformers because they are sensitive to electrical signals and can cause sparking which can trigger fire since there is oil in transformers cooling coils. Optical fibers are electrically inert so this system will prove to be ideal for this application. Results of investigations carried out by simulating a configuration of Optical Fiber Temperature Sensor for transformers based on microbending using Matlab as a simulation tool to evaluate the effectiveness of this sensor have been communicated through this manuscript. The results are in the form of graphs of intensity modulation vs. the temperature.

  12. The roles of electronic books in the transformation of learning and instruction

    NARCIS (Netherlands)

    Huang, Ronghuai; Chen, Nian-Shing; Kang, Myunghee; McKenney, Susan; Churchill, Daniel

    2014-01-01

    Huang, R., Chen, N., Kang, M. McKenney, S. & Churchill, D. (2013). The roles of electronic books in the transformation of learning and instruction. In N. Chen, R. Huang, Kinshuk, Y. Li, D. G. Sampson (Eds.) Proceedings of the IEEE 13th International Conference on Advanced Learning Technologies

  13. Decomposition of PCBs in transformer oil using an electron beam accelerator

    International Nuclear Information System (INIS)

    Jung, In-Ha; Lee, Myun-Joo; Mah, Yoon-Jung

    2012-01-01

    Decomposition of PCBs in commercially used transformer oil used for more than 30 years has been carried out at normal temperature and pressure without any additives using an electron beam accelerator. The experiments were carried out in two ways: batch and continuous pilot plant with 1.5 MeV of energy, a 50 mA current, and 75 kW of power in a commercial scale accelerator. The electron beam irradiation seemed to transform large molecular weight compounds into lower ones, but the impact was considered too small on the physical properties of oil. Residual concentrations of PCBs after irradiation depend on the absorption dose of the electron beam energy, but aliphatic chloride compounds were produced at higher doses of irradiation. As the results from FT-NMR, chloride ions decomposed from the PCBs are likely to react with aliphatic hydro carbon compounds rather than existing as free radical ions in the transformer oil. Since this is a dry process, treated oil can be used as cutting oil or machine oil for heavy equipment without any additional treatments. - Highlights: ► We developed a novel technology of decomposing PCBs in transformer oil using an electron beam. ► Distinct feature is accomplishing at ambient temperature and pressure without any additives. ► Residual PCBs were depended on absorption dose, but aliphatic chlorides were produced at higher dose. ► Treated oil can be reused as heating oil with chlorine removal technology developed here.

  14. Phase transformations in TiAl based alloys

    International Nuclear Information System (INIS)

    Zghal, Slim; Thomas, Marc; Naka, Shigehisa; Finel, Alphonse; Couret, Alain

    2005-01-01

    Microstructural characteristics of a fully lamellar Ti 49 Al 47 Cr 2 Nb 2 alloy have been investigated in different annealed conditions by quantitative transmission electron microscopy. Statistical analyses have yielded clear information about the γ-γ interfaces, the respective orientation groups of the γ phase, and the distribution of orientational variants. From the results, three sequences of lamellar transformation have been identified with decreasing temperature: (1) a high-temperature heterogeneous transformation characterized by the nucleation of isolated primary γ lamellae mostly belonging to the same orientation group and having locally the same order; (2) a low-temperature homogeneous transformation in the ordered α 2 phase characterized by the formation of a fine lamellar structure with an even distribution of the orientation groups and a random ordering of γ lamellae; and (3) a coherent interfacial transformation at the α 2 /γ interfaces characterized by the nucleation of ultra-fine twin related lamellae. Finally, the driving forces for these various transformations as well as the nucleation mechanisms of γ lamellae involved in these transformations are discussed

  15. Effect of Vavilov–Cherenkov radiation cone transformation upon entry of a relativistic electron into a substance layer

    Energy Technology Data Exchange (ETDEWEB)

    Kishchin, I. A.; Kubankin, A. S., E-mail: kubankin@bsu.edu.ru; Nikulicheva, T. B.; Al-Omari; Sotnikov, A. V.; Starovoitov, A. S. [Belgorod National Research University (Russian Federation)

    2016-12-15

    Transformation of the Vavilov–Cherenkov radiation cone under grazing interaction of a relativistic electron with a layer of substance is theoretically studied. It is shown that this effect can occur when the electron enters the substance layer.

  16. Transformation

    DEFF Research Database (Denmark)

    Bock, Lars Nicolai

    2011-01-01

    Artiklen diskuterer ordet "transformation" med udgangspunkt i dels hvorledes ordet bruges i arkitektfaglig terminologi og dels med fokus på ordets potentielle indhold og egnethed i samme teminologi.......Artiklen diskuterer ordet "transformation" med udgangspunkt i dels hvorledes ordet bruges i arkitektfaglig terminologi og dels med fokus på ordets potentielle indhold og egnethed i samme teminologi....

  17. TRANSFORMATION

    Energy Technology Data Exchange (ETDEWEB)

    LACKS,S.A.

    2003-10-09

    Transformation, which alters the genetic makeup of an individual, is a concept that intrigues the human imagination. In Streptococcus pneumoniae such transformation was first demonstrated. Perhaps our fascination with genetics derived from our ancestors observing their own progeny, with its retention and assortment of parental traits, but such interest must have been accelerated after the dawn of agriculture. It was in pea plants that Gregor Mendel in the late 1800s examined inherited traits and found them to be determined by physical elements, or genes, passed from parents to progeny. In our day, the material basis of these genetic determinants was revealed to be DNA by the lowly bacteria, in particular, the pneumococcus. For this species, transformation by free DNA is a sexual process that enables cells to sport new combinations of genes and traits. Genetic transformation of the type found in S. pneumoniae occurs naturally in many species of bacteria (70), but, initially only a few other transformable species were found, namely, Haemophilus influenzae, Neisseria meningitides, Neisseria gonorrheae, and Bacillus subtilis (96). Natural transformation, which requires a set of genes evolved for the purpose, contrasts with artificial transformation, which is accomplished by shocking cells either electrically, as in electroporation, or by ionic and temperature shifts. Although such artificial treatments can introduce very small amounts of DNA into virtually any type of cell, the amounts introduced by natural transformation are a million-fold greater, and S. pneumoniae can take up as much as 10% of its cellular DNA content (40).

  18. A survey and comparison of transformation tools based on the transformation tool contest

    NARCIS (Netherlands)

    Jakumeit, E.; Van Gorp, P.; Buchwald, S.; Rose, L.; Wagelaar, D.; Dan, L.; Hegedüs, Á; Hermannsdörfer, M.; Horn, T.; Kalnina, E.; Krause, C.; Lano, K.; Lepper, M.; Rensink, Arend; Rose, L.M.; Wätzoldt, S.; Mazanek, S.

    Model transformation is one of the key tasks in model-driven engineering and relies on the efficient matching and modification of graph-based data structures; its sibling graph rewriting has been used to successfully model problems in a variety of domains. Over the last years, a wide range of graph

  19. Transformation-based spherical cloaks designed by an implicit transformation-independent method: theory and optimization

    International Nuclear Information System (INIS)

    Novitsky, Andrey; Qiu, C-W; Zouhdi, Said

    2009-01-01

    Based on the concept of the cloak generating function, we propose an implicit transformation-independent method for the required parameters of spherical cloaks without knowing the needed coordinate transformation beforehand. A non-ideal discrete model is used to calculate and optimize the total scattering cross-sections of different profiles of the generating function. A bell-shaped quadratic spherical cloak is found to be the best candidate, which is further optimized by controlling the design parameters involved. Such improved invisibility is steady even when the model is highly discretized.

  20. Quantitative Comparison of Tolerance-Based Feature Transforms

    OpenAIRE

    Reniers, Dennie; Telea, Alexandru

    2006-01-01

    Tolerance-based feature transforms (TFTs) assign to each pixel in an image not only the nearest feature pixels on the boundary (origins), but all origins from the minimum distance up to a user-defined tolerance. In this paper, we compare four simple-to-implement methods for computing TFTs for binary images. Of these, two are novel methods and two extend existing distance transform algorithms. We quantitatively and qualitatively compare all algorithms on speed and accuracy of both distance and...

  1. TRANSFORMER

    Science.gov (United States)

    Baker, W.R.

    1959-08-25

    Transformers of a type adapted for use with extreme high power vacuum tubes where current requirements may be of the order of 2,000 to 200,000 amperes are described. The transformer casing has the form of a re-entrant section being extended through an opening in one end of the cylinder to form a coaxial terminal arrangement. A toroidal multi-turn primary winding is disposed within the casing in coaxial relationship therein. In a second embodiment, means are provided for forming the casing as a multi-turn secondary. The transformer is characterized by minimized resistance heating, minimized external magnetic flux, and an economical construction.

  2. Environmental transformations and ecological effects of iron-based nanoparticles.

    Science.gov (United States)

    Lei, Cheng; Sun, Yuqing; Tsang, Daniel C W; Lin, Daohui

    2018-01-01

    The increasing application of iron-based nanoparticles (NPs), especially high concentrations of zero-valent iron nanoparticles (nZVI), has raised concerns regarding their environmental behavior and potential ecological effects. In the environment, iron-based NPs undergo physical, chemical, and/or biological transformations as influenced by environmental factors such as pH, ions, dissolved oxygen, natural organic matter (NOM), and biotas. This review presents recent research advances on environmental transformations of iron-based NPs, and articulates their relationships with the observed toxicities. The type and extent of physical, chemical, and biological transformations, including aggregation, oxidation, and bio-reduction, depend on the properties of NPs and the receiving environment. Toxicities of iron-based NPs to bacteria, algae, fish, and plants are increasingly observed, which are evaluated with a particular focus on the underlying mechanisms. The toxicity of iron-based NPs is a function of their properties, tolerance of test organisms, and environmental conditions. Oxidative stress induced by reactive oxygen species is considered as the primary toxic mechanism of iron-based NPs. Factors influencing the toxicity of iron-based NPs are addressed and environmental transformations play a significant role, for example, surface oxidation or coating by NOM generally lowers the toxicity of nZVI. Research gaps and future directions are suggested with an aim to boost concerted research efforts on environmental transformations and toxicity of iron-based NPs, e.g., toxicity studies of transformed NPs in field, expansion of toxicity endpoints, and roles of laden contaminants and surface coating. This review will enhance our understanding of potential risks of iron-based NPs and proper uses of environmentally benign NPs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Electron beam instabilities in unmagnetized plasmas via the Stieltjes transform (linear theory and nonlinear mode coupling)

    International Nuclear Information System (INIS)

    Krishan, S.

    2007-01-01

    The Stieltjes transform has been used in place of a more common Laplace transform to determine the time evolution of the self-consistent field (SCF) of an unmagnetized semi-infinite plasma, where the plasma electrons together with a primary and a low-density secondary electron beam move perpendicular to the boundary surface. The secondary beam is produced when the primary beam strikes the grid. Such a plasma system has been investigated by Griskey and Stanzel [M. C. Grisky and R. L. Stenzel, Phys. Rev. Lett. 82, 556 (1999)]. The physical phenomenon, observed in their experiment, has been named by them as ''secondary beam instability.'' The character of the instability observed in the experiment is not the same as predicted by the conventional treatments--the field amplitude does not grow with time. In the frequency spectrum, the theory predicts peak values in the amplitude of SCF at the plasma frequency of plasma and secondary beam electrons, decreasing above and below it. The Stieltjes transform for functions, growing exponentially in the long time limit, does not exist, while the Laplace transform technique gives only exponentially growing solutions. Therefore, it should be interesting to know the kind of solutions that an otherwise physically unstable plasma will yield. In the high-frequency limit, the plasma has been found to respond to any arbitrary frequency of the initial field differentiated only by the strength of the resulting SCF. The condition required for exponential growth in the conventional treatments, and the condition for maximum amplitude (with respect to frequency) in the present treatment, have been found to be the same. Nonlinear mode coupling between the modes excited by the plasma electrons and the low-density secondary beam gives rise to two frequency-dependent peaks in the field amplitude, symmetrically located about the much stronger peak due to the plasma electrons, as predicted by the experiment

  4. Agrobacterium-Mediated Transformation of Leaf Base Segments.

    Science.gov (United States)

    Gasparis, Sebastian

    2017-01-01

    Agrobacterium-mediated transformation has become a routine method of genetic engineering of cereals, gradually replacing the biolistic protocols. Simple integration patterns of transgenic loci, decent transformation efficiency, and technical simplicity are the main advantages offered by this method. Here we present a detailed protocol for the production of transgenic oat plants by Agrobacterium-mediated transformation of leaf base segments. The use of leaf explants as target tissues for transformation and in vitro regeneration of transgenic plants may be a good alternative for genotypes which are not susceptible to regeneration from immature or mature embryos. We also describe the biochemical and molecular analysis procedures of the transgenic plants including a GUS histochemical assay, and Southern blot, both of which are optimized for application in oat.

  5. Image Retrieval Algorithm Based on Discrete Fractional Transforms

    Science.gov (United States)

    Jindal, Neeru; Singh, Kulbir

    2013-06-01

    The discrete fractional transforms is a signal processing tool which suggests computational algorithms and solutions to various sophisticated applications. In this paper, a new technique to retrieve the encrypted and scrambled image based on discrete fractional transforms has been proposed. Two-dimensional image was encrypted using discrete fractional transforms with three fractional orders and two random phase masks placed in the two intermediate planes. The significant feature of discrete fractional transforms benefits from its extra degree of freedom that is provided by its fractional orders. Security strength was enhanced (1024!)4 times by scrambling the encrypted image. In decryption process, image retrieval is sensitive for both correct fractional order keys and scrambling algorithm. The proposed approach make the brute force attack infeasible. Mean square error and relative error are the recital parameters to verify validity of proposed method.

  6. Design Transformations for Rule-based Procedural Modeling

    KAUST Repository

    Lienhard, Stefan; Lau, Cheryl; Mü ller, Pascal; Wonka, Peter; Pauly, Mark

    2017-01-01

    We introduce design transformations for rule-based procedural models, e.g., for buildings and plants. Given two or more procedural designs, each specified by a grammar, a design transformation combines elements of the existing designs to generate new designs. We introduce two technical components to enable design transformations. First, we extend the concept of discrete rule switching to rule merging, leading to a very large shape space for combining procedural models. Second, we propose an algorithm to jointly derive two or more grammars, called grammar co-derivation. We demonstrate two applications of our work: we show that our framework leads to a larger variety of models than previous work, and we show fine-grained transformation sequences between two procedural models.

  7. Design Transformations for Rule-based Procedural Modeling

    KAUST Repository

    Lienhard, Stefan

    2017-05-24

    We introduce design transformations for rule-based procedural models, e.g., for buildings and plants. Given two or more procedural designs, each specified by a grammar, a design transformation combines elements of the existing designs to generate new designs. We introduce two technical components to enable design transformations. First, we extend the concept of discrete rule switching to rule merging, leading to a very large shape space for combining procedural models. Second, we propose an algorithm to jointly derive two or more grammars, called grammar co-derivation. We demonstrate two applications of our work: we show that our framework leads to a larger variety of models than previous work, and we show fine-grained transformation sequences between two procedural models.

  8. Effectiveness of Discovery Learning-Based Transformation Geometry Module

    Science.gov (United States)

    Febriana, R.; Haryono, Y.; Yusri, R.

    2017-09-01

    Development of transformation geometry module is conducted because the students got difficulties to understand the existing book. The purpose of the research was to find out the effectiveness of discovery learning-based transformation geometry module toward student’s activity. Model of the development was Plomp model consisting preliminary research, prototyping phase and assessment phase. The research was focused on assessment phase where it was to observe the designed product effectiveness. The instrument was observation sheet. The observed activities were visual activities, oral activities, listening activities, mental activities, emotional activities and motor activities. Based on the result of the research, it is found that visual activities, learning activities, writing activities, the student’s activity is in the criteria very effective. It can be concluded that the use of discovery learning-based transformation geometry module use can increase the positive student’s activity and decrease the negative activity.

  9. Structural and electronic transformation in low-angle twisted bilayer graphene

    Science.gov (United States)

    Gargiulo, Fernando; Yazyev, Oleg V.

    2018-01-01

    Experiments on bilayer graphene unveiled a fascinating realization of stacking disorder where triangular domains with well-defined Bernal stacking are delimited by a hexagonal network of strain solitons. Here we show by means of numerical simulations that this is a consequence of a structural transformation of the moiré pattern inherent to twisted bilayer graphene taking place at twist angles θ below a crossover angle θ\\star=1.2\\circ . The transformation is governed by the interplay between the interlayer van der Waals interaction and the in-plane strain field, and is revealed by a change in the functional form of the twist energy density. This transformation unveils an electronic regime characteristic of vanishing twist angles in which the charge density converges, though not uniformly, to that of ideal bilayer graphene with Bernal stacking. On the other hand, the stacking domain boundaries form a distinct charge density pattern that provides the STM signature of the hexagonal solitonic network.

  10. An accurate system for onsite calibration of electronic transformers with digital output

    International Nuclear Information System (INIS)

    Zhi Zhang; Li Hongbin

    2012-01-01

    Calibration systems with digital output are used to replace conventional calibration systems because of principle diversity and characteristics of digital output of electronic transformers. But precision and unpredictable stability limit their onsite application even development. So fully considering the factors influencing accuracy of calibration system and employing simple but reliable structure, an all-digital calibration system with digital output is proposed in this paper. In complicated calibration environments, precision and dynamic range are guaranteed by A/D converter with 24-bit resolution, synchronization error limit is nanosecond by using the novelty synchronization method. In addition, an error correction algorithm based on the differential method by using two-order Hanning convolution window has good inhibition of frequency fluctuation and inter-harmonics interference. To verify the effectiveness, error calibration was carried out in the State Grid Electric Power Research Institute of China and results show that the proposed system can reach the precision class up to 0.05. Actual onsite calibration shows that the system has high accuracy, and is easy to operate with satisfactory stability.

  11. An accurate system for onsite calibration of electronic transformers with digital output.

    Science.gov (United States)

    Zhi, Zhang; Li, Hong-Bin

    2012-06-01

    Calibration systems with digital output are used to replace conventional calibration systems because of principle diversity and characteristics of digital output of electronic transformers. But precision and unpredictable stability limit their onsite application even development. So fully considering the factors influencing accuracy of calibration system and employing simple but reliable structure, an all-digital calibration system with digital output is proposed in this paper. In complicated calibration environments, precision and dynamic range are guaranteed by A/D converter with 24-bit resolution, synchronization error limit is nanosecond by using the novelty synchronization method. In addition, an error correction algorithm based on the differential method by using two-order Hanning convolution window has good inhibition of frequency fluctuation and inter-harmonics interference. To verify the effectiveness, error calibration was carried out in the State Grid Electric Power Research Institute of China and results show that the proposed system can reach the precision class up to 0.05. Actual onsite calibration shows that the system has high accuracy, and is easy to operate with satisfactory stability.

  12. An accurate system for onsite calibration of electronic transformers with digital output

    Energy Technology Data Exchange (ETDEWEB)

    Zhi Zhang; Li Hongbin [CEEE of HuaZhong University of Science and Technology, Wuhan 430074 (China); State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Wuhan 430074 (China)

    2012-06-15

    Calibration systems with digital output are used to replace conventional calibration systems because of principle diversity and characteristics of digital output of electronic transformers. But precision and unpredictable stability limit their onsite application even development. So fully considering the factors influencing accuracy of calibration system and employing simple but reliable structure, an all-digital calibration system with digital output is proposed in this paper. In complicated calibration environments, precision and dynamic range are guaranteed by A/D converter with 24-bit resolution, synchronization error limit is nanosecond by using the novelty synchronization method. In addition, an error correction algorithm based on the differential method by using two-order Hanning convolution window has good inhibition of frequency fluctuation and inter-harmonics interference. To verify the effectiveness, error calibration was carried out in the State Grid Electric Power Research Institute of China and results show that the proposed system can reach the precision class up to 0.05. Actual onsite calibration shows that the system has high accuracy, and is easy to operate with satisfactory stability.

  13. An accurate system for onsite calibration of electronic transformers with digital output

    Science.gov (United States)

    Zhi, Zhang; Li, Hong-Bin

    2012-06-01

    Calibration systems with digital output are used to replace conventional calibration systems because of principle diversity and characteristics of digital output of electronic transformers. But precision and unpredictable stability limit their onsite application even development. So fully considering the factors influencing accuracy of calibration system and employing simple but reliable structure, an all-digital calibration system with digital output is proposed in this paper. In complicated calibration environments, precision and dynamic range are guaranteed by A/D converter with 24-bit resolution, synchronization error limit is nanosecond by using the novelty synchronization method. In addition, an error correction algorithm based on the differential method by using two-order Hanning convolution window has good inhibition of frequency fluctuation and inter-harmonics interference. To verify the effectiveness, error calibration was carried out in the State Grid Electric Power Research Institute of China and results show that the proposed system can reach the precision class up to 0.05. Actual onsite calibration shows that the system has high accuracy, and is easy to operate with satisfactory stability.

  14. Electronic structure and phase stability during martensitic transformation in Al-doped ZrCu intermetallics

    International Nuclear Information System (INIS)

    Qiu Feng; Shen Ping; Liu Tao; Lin Qiaoli; Jiang Qichuan

    2010-01-01

    Martensitic transformation, phase stability and electronic structure of Al-doped ZrCu intermetallics were investigated by experiments and first-principles calculations using the pseudopotentials plane wave method. The formation energy calculations indicate that the stability of the ZrCu phase increases with the increasing Al content. Al plays a decisive role in controlling the formation and microstructures of the martensite phases in Zr-Cu-Al alloys. The total energy difference between ZrCu (B2) austenite and ZrCu martensite plays an important role in the martensitic transformation. The phase stability is dependent on its electronic structure. The densities of states (DOS) of the intermetallics were discussed in detail.

  15. Research on fault characteristics about switching component failures for distribution electronic power transformers

    Science.gov (United States)

    Sang, Z. X.; Huang, J. Q.; Yan, J.; Du, Z.; Xu, Q. S.; Lei, H.; Zhou, S. X.; Wang, S. C.

    2017-11-01

    The protection is an essential part for power device, especially for those in power grid, as the failure may cost great losses to the society. A study on the voltage and current abnormality in the power electronic devices in Distribution Electronic Power Transformer (D-EPT) during the failures on switching components is presented, as well as the operational principles for 10 kV rectifier, 10 kV/400 V DC-DC converter and 400 V inverter in D-EPT. Derived from the discussion on the effects of voltage and current distortion, the fault characteristics as well as a fault diagnosis method for D-EPT are introduced.

  16. Community-Based Ecotourism: The Transformation of Local Community

    Directory of Open Access Journals (Sweden)

    Pookhao Nantira

    2014-01-01

    Full Text Available Community-based ecotourism (CBET is considered a sustainable form of tourism that improves the quality of life of hosts at the tourist destination. Scholars have yet to explore the long-term operation of CBET in relation to its effects on the local way of life. Consequently, the purpose of this paper is to examine the transformation of a local community due to the operation of CBET in relation to sociocultural, economic and environmental aspects. The findings reveal that the community encounters both positive and negative impacts of transformation. However, unintended impacts of the CBET operation lay embedded in the transformation of relationships among the community members. The study identifies that close relationships among the villagers has been initially transformed to loose relationships due to forgotten communal goals; CBET has transformed from being a conservation tool to being a business-oriented goal which causes conflicts of interest among local people and alters traditional social structure. The study also agrees with the notion of social exchange theory for villagers to enhance environmental sustainability, and proposes that slight inequalities of benefits received from CBET causes social transformation at the local level.

  17. QR code-based non-linear image encryption using Shearlet transform and spiral phase transform

    Science.gov (United States)

    Kumar, Ravi; Bhaduri, Basanta; Hennelly, Bryan

    2018-02-01

    In this paper, we propose a new quick response (QR) code-based non-linear technique for image encryption using Shearlet transform (ST) and spiral phase transform. The input image is first converted into a QR code and then scrambled using the Arnold transform. The scrambled image is then decomposed into five coefficients using the ST and the first Shearlet coefficient, C1 is interchanged with a security key before performing the inverse ST. The output after inverse ST is then modulated with a random phase mask and further spiral phase transformed to get the final encrypted image. The first coefficient, C1 is used as a private key for decryption. The sensitivity of the security keys is analysed in terms of correlation coefficient and peak signal-to noise ratio. The robustness of the scheme is also checked against various attacks such as noise, occlusion and special attacks. Numerical simulation results are shown in support of the proposed technique and an optoelectronic set-up for encryption is also proposed.

  18. Decomposition of PCBs in transformer oil using an electron beam accelerator

    Science.gov (United States)

    Jung, In-Ha; Lee, Myun-Joo; Mah, Yoon-Jung

    2012-07-01

    Decomposition of PCBs in commercially used transformer oil used for more than 30 years has been carried out at normal temperature and pressure without any additives using an electron beam accelerator. The experiments were carried out in two ways: batch and continuous pilot plant with 1.5 MeV of energy, a 50 mA current, and 75 kW of power in a commercial scale accelerator. The electron beam irradiation seemed to transform large molecular weight compounds into lower ones, but the impact was considered too small on the physical properties of oil. Residual concentrations of PCBs after irradiation depend on the absorption dose of the electron beam energy, but aliphatic chloride compounds were produced at higher doses of irradiation. As the results from FT-NMR, chloride ions decomposed from the PCBs are likely to react with aliphatic hydro carbon compounds rather than existing as free radical ions in the transformer oil. Since this is a dry process, treated oil can be used as cutting oil or machine oil for heavy equipment without any additional treatments.

  19. Electron backscatter diffraction studies of focused ion beam induced phase transformation in cobalt

    Energy Technology Data Exchange (ETDEWEB)

    Jones, H.G., E-mail: helen.jones@npl.co.uk [National Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW (United Kingdom); Day, A.P. [Aunt Daisy Scientific Ltd, Claremont House, High St, Lydney GL15 5DX (United Kingdom); Cox, D.C. [National Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW (United Kingdom); Advanced Technology Institute, University of Surrey, Guildford GU2 7XH (United Kingdom)

    2016-10-15

    A focused ion beam microscope was used to induce cubic to hexagonal phase transformation in a cobalt alloy, of similar composition to that of the binder phase in a hardmetal, in a controlled manner at 0°, 45° and 80° ion incident angles. The cobalt had an average grain size of ~ 20 μm, allowing multiple orientations to be studied, exposed to a range of doses between 6 × 10{sup 7} and 2 × 10{sup 10} ions/μm{sup 2}. Electron backscatter diffraction (EBSD) was used to determine the original and induced phase orientations, and area fractions, before and after the ion beam exposure. On average, less phase transformation was observed at higher incident angles and after lower ion doses. However there was an orientation effect where grains with an orientation close to (111) planes were most susceptible to phase transformation, and (101) the least, where grains partially and fully transformed at varying ion doses. - Highlights: •Ion-induced phase change in FCC cobalt was observed at multiple incidence angles. •EBSD was used to study the relationship between grain orientation and transformation. •Custom software analysed ion dose and phase change with respect to grain orientation. •A predictive capability of ion-induced phase change in cobalt was enabled.

  20. Laser induced structural transformation in chalcogenide based superlattices

    International Nuclear Information System (INIS)

    Zallo, Eugenio; Wang, Ruining; Bragaglia, Valeria; Calarco, Raffaella

    2016-01-01

    Superlattices made of alternating layers of nominal GeTe and Sb 2 Te 3 have been studied by micro-Raman spectroscopy. A structural irreversible transformation into ordered GeSbTe alloy is induced by high power laser light exposure. The intensity ratio of anti-Stokes and Stokes scattering under laser illumination gives a maximum average temperature in the sample of 177 °C. The latter is lower than the growth temperature and of 400 °C necessary by annealing to transform the structure in a GeSbTe alloy. The absence of this configuration after in situ annealing even up to 300 °C evidences an electronic excitation induced-transition which brings the system into a different and stable crystalline state.

  1. Laser induced structural transformation in chalcogenide based superlattices

    Energy Technology Data Exchange (ETDEWEB)

    Zallo, Eugenio, E-mail: zallo@pdi-berlin.de; Wang, Ruining; Bragaglia, Valeria; Calarco, Raffaella [Paul-Drude-Institut für Festkörperelektronik, Hausvogteiplatz 5-7, 10117 Berlin (Germany)

    2016-05-30

    Superlattices made of alternating layers of nominal GeTe and Sb{sub 2}Te{sub 3} have been studied by micro-Raman spectroscopy. A structural irreversible transformation into ordered GeSbTe alloy is induced by high power laser light exposure. The intensity ratio of anti-Stokes and Stokes scattering under laser illumination gives a maximum average temperature in the sample of 177 °C. The latter is lower than the growth temperature and of 400 °C necessary by annealing to transform the structure in a GeSbTe alloy. The absence of this configuration after in situ annealing even up to 300 °C evidences an electronic excitation induced-transition which brings the system into a different and stable crystalline state.

  2. Analytical electron microscope study of the omega phase transformation in a zirconium--niobium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zaluzec, N.J.

    1979-06-01

    An in-situ study of the as-quenched omega phase transformation in Zr--15% Nb was conducted between the temperatures of 77 and 300/sup 0/K using analytical electron microscopy. The domain size of the omega regions observed in this investigation was on the order of 30 A, consistent with previous observations in this system. No alignment of omega domains along <222> directions of the bcc lattice was observed and in-situ thermal cycling experiments failed to produce a long period structure of alternating ..beta.. and ..omega.. phase regions as predicted by one theory of this transformation. Several techniques of microstructural analysis were developed, refined, and standardized. Grouped under the general classification of Analytical Electron Microscopy (AEM) they provide the experimentalist with a unique tool for the microcharacterization of solids, allowing semiquantitative to quantitative analysis of the morphology, crystallography, elemental composition, and electronic structure of regions as small as 20 A in diameter. These techniques have complications, and it was necessary to study the AEM system used in this work so that instrumental artifacts which invalidate the information produced in the microscope environment might be eliminated. Once these factors had been corrected, it was possible to obtain a wealth of information about the microvolume of material under investigation. The microanalytical techniques employed during this research include: energy dispersive x-ray spectroscopy (EDS) using both conventional and scanning transmission electron microscopy (CTEM, STEM), transmission scanning electron diffraction (TSED), the stationary diffraction pattern technique, and electron energy loss spectroscopy (ELS) using a dedicated scanning transmission electron microscope (DSTEM).

  3. Analytical electron microscope study of the omega phase transformation in a zirconium--niobium alloy

    International Nuclear Information System (INIS)

    Zaluzec, N.J.

    1979-06-01

    An in-situ study of the as-quenched omega phase transformation in Zr--15% Nb was conducted between the temperatures of 77 and 300 0 K using analytical electron microscopy. The domain size of the omega regions observed in this investigation was on the order of 30 A, consistent with previous observations in this system. No alignment of omega domains along directions of the bcc lattice was observed and in-situ thermal cycling experiments failed to produce a long period structure of alternating β and ω phase regions as predicted by one theory of this transformation. Several techniques of microstructural analysis were developed, refined, and standardized. Grouped under the general classification of Analytical Electron Microscopy (AEM) they provide the experimentalist with a unique tool for the microcharacterization of solids, allowing semiquantitative to quantitative analysis of the morphology, crystallography, elemental composition, and electronic structure of regions as small as 20 A in diameter. These techniques have complications, and it was necessary to study the AEM system used in this work so that instrumental artifacts which invalidate the information produced in the microscope environment might be eliminated. Once these factors had been corrected, it was possible to obtain a wealth of information about the microvolume of material under investigation. The microanalytical techniques employed during this research include: energy dispersive x-ray spectroscopy (EDS) using both conventional and scanning transmission electron microscopy (CTEM, STEM), transmission scanning electron diffraction (TSED), the stationary diffraction pattern technique, and electron energy loss spectroscopy (ELS) using a dedicated scanning transmission electron microscope

  4. Program Transformation to Identify List-Based Parallel Skeletons

    Directory of Open Access Journals (Sweden)

    Venkatesh Kannan

    2016-07-01

    Full Text Available Algorithmic skeletons are used as building-blocks to ease the task of parallel programming by abstracting the details of parallel implementation from the developer. Most existing libraries provide implementations of skeletons that are defined over flat data types such as lists or arrays. However, skeleton-based parallel programming is still very challenging as it requires intricate analysis of the underlying algorithm and often uses inefficient intermediate data structures. Further, the algorithmic structure of a given program may not match those of list-based skeletons. In this paper, we present a method to automatically transform any given program to one that is defined over a list and is more likely to contain instances of list-based skeletons. This facilitates the parallel execution of a transformed program using existing implementations of list-based parallel skeletons. Further, by using an existing transformation called distillation in conjunction with our method, we produce transformed programs that contain fewer inefficient intermediate data structures.

  5. Exploring Phonetic Realization in Danish by Transformation-Based Learning

    DEFF Research Database (Denmark)

    Uneson, Marcus; Schachtenhaufen, Ruben

    2011-01-01

    We align phonemic and semi-narrow phonetic transcriptions in the DanPASS corpus and extend the phonemic description with sound classes and with traditional phonetic features. From this representation, we induce rules for phonetic realization by Transformation-Based Learning (TBL). The rules thus ...

  6. Piezoelectric transformer based power converters; design and control

    DEFF Research Database (Denmark)

    Rødgaard, Martin Schøler

    The last two decades of research into piezoelectric transformer (PT) based power converters have led to some extensive improvements of the technology, but it still struggles to get its commercial success. This calls for further research and has been the subject of this work, in order to enable...

  7. Quantitative Comparison of Tolerance-Based Feature Transforms

    NARCIS (Netherlands)

    Reniers, Dennie; Telea, Alexandru

    2006-01-01

    Tolerance-based feature transforms (TFTs) assign to each pixel in an image not only the nearest feature pixels on the boundary (origins), but all origins from the minimum distance up to a user-defined tolerance. In this paper, we compare four simple-to-implement methods for computing TFTs for binary

  8. Photonic Hilbert transformers based on laterally apodized integrated waveguide Bragg gratings on a SOI wafer.

    Science.gov (United States)

    Bazargani, Hamed Pishvai; Burla, Maurizio; Chrostowski, Lukas; Azaña, José

    2016-11-01

    We experimentally demonstrate high-performance integer and fractional-order photonic Hilbert transformers based on laterally apodized Bragg gratings in a silicon-on-insulator technology platform. The sub-millimeter-long gratings have been fabricated using single-etch electron beam lithography, and the resulting HT devices offer operation bandwidths approaching the THz range, with time-bandwidth products between 10 and 20.

  9. Digital Correlation based on Wavelet Transform for Image Detection

    International Nuclear Information System (INIS)

    Barba, L; Vargas, L; Torres, C; Mattos, L

    2011-01-01

    In this work is presented a method for the optimization of digital correlators to improve the characteristic detection on images using wavelet transform as well as subband filtering. It is proposed an approach of wavelet-based image contrast enhancement in order to increase the performance of digital correlators. The multiresolution representation is employed to improve the high frequency content of images taken into account the input contrast measured for the original image. The energy of correlation peaks and discrimination level of several objects are improved with this technique. To demonstrate the potentiality in extracting characteristics using the wavelet transform, small objects inside reference images are detected successfully.

  10. Process identification method based on the Z transformation

    International Nuclear Information System (INIS)

    Zwingelstein, G.

    1968-01-01

    A simple method is described for identifying the transfer function of a linear retard-less system, based on the inversion of the Z transformation of the transmittance using a computer. It is assumed in this study that the signals at the entrance and at the exit of the circuit considered are of the deterministic type. The study includes: the theoretical principle of the inversion of the Z transformation, details about programming simulation, and identification of filters whose degrees vary from the first to the fifth order. (authors) [fr

  11. A new perspective on relativistic transformation: formulation of the differential Lorentz transformation based on first principles

    International Nuclear Information System (INIS)

    Huang, Young-Sea

    2010-01-01

    The differential Lorentz transformation is formulated solely from the principle of relativity and the invariance of the speed of light. The differential Lorentz transformation transforms physical quantities, instead of space-time coordinates, to keep laws of nature form-invariant among inertial frames. The new relativistic transformation fulfills the principle of relativity, whereas the usual Lorentz transformation of space-time coordinates does not. Furthermore, the new relativistic transformation is compatible with quantum mechanics. The formulation herein provides theoretical foundations for the differential Lorentz transformation as the fundamental relativistic transformation.

  12. Generalized formulation of an encryption system based on a joint transform correlator and fractional Fourier transform

    International Nuclear Information System (INIS)

    Vilardy, Juan M; Millán, María S; Pérez-Cabré, Elisabet; Torres, Yezid

    2014-01-01

    We propose a generalization of the encryption system based on double random phase encoding (DRPE) and a joint transform correlator (JTC), from the Fourier domain to the fractional Fourier domain (FrFD) by using the fractional Fourier operators, such as the fractional Fourier transform (FrFT), fractional traslation, fractional convolution and fractional correlation. Image encryption systems based on a JTC architecture in the FrFD usually produce low quality decrypted images. In this work, we present two approaches to improve the quality of the decrypted images, which are based on nonlinear processing applied to the encrypted function (that contains the joint fractional power spectrum, JFPS) and the nonzero-order JTC in the FrFD. When the two approaches are combined, the quality of the decrypted image is higher. In addition to the advantages introduced by the implementation of the DRPE using a JTC, we demonstrate that the proposed encryption system in the FrFD preserves the shift-invariance property of the JTC-based encryption system in the Fourier domain, with respect to the lateral displacement of both the key random mask in the decryption process and the retrieval of the primary image. The feasibility of this encryption system is verified and analyzed by computer simulations. (paper)

  13. Fukunaga-Koontz transform based dimensionality reduction for hyperspectral imagery

    Science.gov (United States)

    Ochilov, S.; Alam, M. S.; Bal, A.

    2006-05-01

    Fukunaga-Koontz Transform based technique offers some attractive properties for desired class oriented dimensionality reduction in hyperspectral imagery. In FKT, feature selection is performed by transforming into a new space where feature classes have complimentary eigenvectors. Dimensionality reduction technique based on these complimentary eigenvector analysis can be described under two classes, desired class and background clutter, such that each basis function best represent one class while carrying the least amount of information from the second class. By selecting a few eigenvectors which are most relevant to desired class, one can reduce the dimension of hyperspectral cube. Since the FKT based technique reduces data size, it provides significant advantages for near real time detection applications in hyperspectral imagery. Furthermore, the eigenvector selection approach significantly reduces computation burden via the dimensionality reduction processes. The performance of the proposed dimensionality reduction algorithm has been tested using real-world hyperspectral dataset.

  14. In Situ Transmission Electron Microscopy Study of Electron Beam-Induced Transformations in Colloidal Cesium Lead Halide Perovskite Nanocrystals

    Science.gov (United States)

    2017-01-01

    An increasing number of studies have recently reported the rapid degradation of hybrid and all-inorganic lead halide perovskite nanocrystals under electron beam irradiation in the transmission electron microscope, with the formation of nanometer size, high contrast particles. The nature of these nanoparticles and the involved transformations in the perovskite nanocrystals are still a matter of debate. Herein, we have studied the effects of high energy (80/200 keV) electron irradiation on colloidal cesium lead bromide (CsPbBr3) nanocrystals with different shapes and sizes, especially 3 nm thick nanosheets, a morphology that facilitated the analysis of the various ongoing processes. Our results show that the CsPbBr3 nanocrystals undergo a radiolysis process, with electron stimulated desorption of a fraction of bromine atoms and the reduction of a fraction of Pb2+ ions to Pb0. Subsequently Pb0 atoms diffuse and aggregate, giving rise to the high contrast particles, as previously reported by various groups. The diffusion is facilitated by both high temperature and electron beam irradiation. The early stage Pb nanoparticles are epitaxially bound to the parent CsPbBr3 lattice, and evolve into nonepitaxially bound Pb crystals upon further irradiation, leading to local amorphization and consequent dismantling of the CsPbBr3 lattice. The comparison among CsPbBr3 nanocrystals with various shapes and sizes evidences that the damage is particularly pronounced at the corners and edges of the surface, due to a lower diffusion barrier for Pb0 on the surface than inside the crystal and the presence of a larger fraction of under-coordinated atoms. PMID:28122188

  15. Note: An improved calibration system with phase correction for electronic transformers with digital output.

    Science.gov (United States)

    Cheng, Han-miao; Li, Hong-bin

    2015-08-01

    The existing electronic transformer calibration systems employing data acquisition cards cannot satisfy some practical applications, because the calibration systems have phase measurement errors when they work in the mode of receiving external synchronization signals. This paper proposes an improved calibration system scheme with phase correction to improve the phase measurement accuracy. We employ NI PCI-4474 to design a calibration system, and the system has the potential to receive external synchronization signals and reach extremely high accuracy classes. Accuracy verification has been carried out in the China Electric Power Research Institute, and results demonstrate that the system surpasses the accuracy class 0.05. Furthermore, this system has been used to test the harmonics measurement accuracy of all-fiber optical current transformers. In the same process, we have used an existing calibration system, and a comparison of the test results is presented. The system after improvement is suitable for the intended applications.

  16. Note: An improved calibration system with phase correction for electronic transformers with digital output

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Han-miao, E-mail: chenghanmiao@hust.edu.cn; Li, Hong-bin, E-mail: lihongbin@hust.edu.cn [CEEE of Huazhong University of Science and Technology, Wuhan 430074 (China); State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Wuhan 430074 (China)

    2015-08-15

    The existing electronic transformer calibration systems employing data acquisition cards cannot satisfy some practical applications, because the calibration systems have phase measurement errors when they work in the mode of receiving external synchronization signals. This paper proposes an improved calibration system scheme with phase correction to improve the phase measurement accuracy. We employ NI PCI-4474 to design a calibration system, and the system has the potential to receive external synchronization signals and reach extremely high accuracy classes. Accuracy verification has been carried out in the China Electric Power Research Institute, and results demonstrate that the system surpasses the accuracy class 0.05. Furthermore, this system has been used to test the harmonics measurement accuracy of all-fiber optical current transformers. In the same process, we have used an existing calibration system, and a comparison of the test results is presented. The system after improvement is suitable for the intended applications.

  17. Going digital: a checklist in preparing for hospital-wide electronic medical record implementation and digital transformation.

    Science.gov (United States)

    Scott, Ian A; Sullivan, Clair; Staib, Andrew

    2018-05-24

    Objective In an era of rapid digitisation of Australian hospitals, practical guidance is needed in how to successfully implement electronic medical records (EMRs) as both a technical innovation and a major transformative change in clinical care. The aim of the present study was to develop a checklist that clearly and comprehensively defines the steps that best prepare hospitals for EMR implementation and digital transformation. Methods The checklist was developed using a formal methodological framework comprised of: literature reviews of relevant issues; an interactive workshop involving a multidisciplinary group of digital leads from Queensland hospitals; a draft document based on literature and workshop proceedings; and a review and feedback from senior clinical leads. Results The final checklist comprised 19 questions, 13 related to EMR implementation and six to digital transformation. Questions related to the former included organisational considerations (leadership, governance, change leaders, implementation plan), technical considerations (vendor choice, information technology and project management teams, system and hardware alignment with clinician workflows, interoperability with legacy systems) and training (user training, post-go-live contingency plans, roll-out sequence, staff support at point of care). Questions related to digital transformation included cultural considerations (clinically focused vision statement and communication strategy, readiness for change surveys), management of digital disruption syndromes and plans for further improvement in patient care (post-go-live optimisation of digital system, quality and benefit evaluation, ongoing digital innovation). Conclusion This evidence-based, field-tested checklist provides guidance to hospitals planning EMR implementation and separates readiness for EMR from readiness for digital transformation. What is known about the topic? Many hospitals throughout Australia have implemented, or are planning

  18. Transformation dynamics of Ni clusters into NiO rings under electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Knez, Daniel, E-mail: daniel.knez@felmi-zfe.at [Institute of Electron Microscopy and Nanoanalysis, Graz University of Technology, Steyrergasse 17, 8010 Graz (Austria); Graz Centre for Electron Microscopy, Steyrergasse 17, 8010 Graz (Austria); Thaler, Philipp; Volk, Alexander [Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010 Graz (Austria); Kothleitner, Gerald [Institute of Electron Microscopy and Nanoanalysis, Graz University of Technology, Steyrergasse 17, 8010 Graz (Austria); Graz Centre for Electron Microscopy, Steyrergasse 17, 8010 Graz (Austria); Ernst, Wolfgang E. [Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010 Graz (Austria); Hofer, Ferdinand [Institute of Electron Microscopy and Nanoanalysis, Graz University of Technology, Steyrergasse 17, 8010 Graz (Austria); Graz Centre for Electron Microscopy, Steyrergasse 17, 8010 Graz (Austria)

    2017-05-15

    We report the transformation of nickel clusters into NiO rings by an electron beam induced nanoscale Kirkendall effect. High-purity nickel clusters consisting of a few thousand atoms have been used as precursors and were synthesized with the superfluid helium droplet technique. Aberration-corrected, analytical scanning transmission electron microscopy was applied to oxidise and simultaneously analyse the nanostructures. The transient dynamics of the oxidation could be documented by time lapse series using high-angle annular dark-field imaging and electron energy-loss spectroscopy. A two-step Cabrera-Mott oxidation mechanism was identified. It was found that water adsorbed adjacent to the clusters acts as oxygen source for the electron beam induced oxidation. The size-dependent oxidation rate was estimated by quantitative EELS measurements combined with molecular dynamics simulations. Our findings could serve to better control sample changes during examination in an electron microscope, and might provide a methodology to generate other metal oxide nanostructures. - Highlights: • Beam induced conversion of Ni clusters into crystalline NiO rings has been observed. • Ni clusters were grown with the superfluid He-droplet technique. • oxidizeSTEM was utilized to investigate and simultaneously oxidize these clusters. • Oxidation dynamics was captured in real-time. • Cluster sizes and the oxidation rate were estimated via EELS and molecular dynamics.

  19. Foldy-Wouthuysen transformations for the classical relativistic electron. Non grassmannian description

    International Nuclear Information System (INIS)

    Pupasov-Maksimov, Andrey; Deriglazov, Alexei

    2012-01-01

    Full text: We consider a classical model of the relativistic electron proposed by A. Deriglazov in Phys. Lett. A 376 (2012) 309-313. Though this model contains only bosonic variables, its quantization leads to the Dirac equation and one-particle relativistic quantum mechanics of the electron. There are constraints and gauge symmetries, therefore 18 initial variables of the model {x μ , p μ , ω A , π A }, μ is an element of (0,4), A is an element of (0,5) do not correspond to the observable quantities. There are 10 physical degrees of freedom implying another set of 10 gauge invariant variables which will be interpreted as physically observable quantities. On the other hand, to have a consistent one-particle relativistic quantum mechanics one has to consider only even operators which do not mix quantum states with positive and negative energy states. Such separation can be obtained with the Foldy-Wouthuysen transformation and leads to the Foldy-Wouthuysen representation with new operators for coordinates and spin (so-called Newton-Wigner coordinates). In the present work we match these to pictures by comparing the choice of the gauge invariant classical variables and the transition to the even operators in the quantum mechanics. We study different canonical transformations of this classical model in order to separate the set of observable quantities from variables with ambiguous dynamics. The constraints of the model in the case of free particle can be chosen in such a way that the Dirac brackets coincide with the Poisson brackets. This choice significantly simplify calculations of transformed variables. Moreover, new variables are canonical variables by construction. It is shown that the following generator of an infinitesimal canonical transformation S=1/2J 5j p j A(p 2 ), can be associated with the Foldy-Wouthuysen transformation. Thus we obtain a classical analog of the Foldy- Wouthuysen transformation. Moreover, the gauge invariant variables in the

  20. Low-energy electron scattering from CO. 2: Ab-initio study using the frame-transformation theory

    Science.gov (United States)

    Chandra, N.

    1976-01-01

    The Wigner-Eisenbud R matrix method has been combined with the frame transformation theory to study electron scattering from molecular systems. The R matrix, calculated at the boundary point of the molecular core radius, has been transformed to the space frame in order to continue the solution of the scattering equations in the outer region where rotational motion of the nuclei is taken into account. This procedure has been applied to a model calculation of thermal energy electron scattering from CO.

  1. Matrix-Vector Based Fast Fourier Transformations on SDR Architectures

    Directory of Open Access Journals (Sweden)

    Y. He

    2008-05-01

    Full Text Available Today Discrete Fourier Transforms (DFTs are applied in various radio standards based on OFDM (Orthogonal Frequency Division Multiplex. It is important to gain a fast computational speed for the DFT, which is usually achieved by using specialized Fast Fourier Transform (FFT engines. However, in face of the Software Defined Radio (SDR development, more general (parallel processor architectures are often desirable, which are not tailored to FFT computations. Therefore, alternative approaches are required to reduce the complexity of the DFT. Starting from a matrix-vector based description of the FFT idea, we will present different factorizations of the DFT matrix, which allow a reduction of the complexity that lies between the original DFT and the minimum FFT complexity. The computational complexities of these factorizations and their suitability for implementation on different processor architectures are investigated.

  2. Saturation Detection-Based Blocking Scheme for Transformer Differential Protection

    Directory of Open Access Journals (Sweden)

    Byung Eun Lee

    2014-07-01

    Full Text Available This paper describes a current differential relay for transformer protection that operates in conjunction with a core saturation detection-based blocking algorithm. The differential current for the magnetic inrush or over-excitation has a point of inflection at the start and end of each saturation period of the transformer core. At these instants, discontinuities arise in the first-difference function of the differential current. The second- and third-difference functions convert the points of inflection into pulses, the magnitudes of which are large enough to detect core saturation. The blocking signal is activated if the third-difference of the differential current is larger than the threshold and is maintained for one cycle. In addition, a method to discriminate between transformer saturation and current transformer (CT saturation is included. The performance of the proposed blocking scheme was compared with that of a conventional harmonic blocking method. The test results indicate that the proposed scheme successfully discriminates internal faults even with CT saturation from the magnetic inrush, over-excitation, and external faults with CT saturation, and can significantly reduce the operating time delay of the relay.

  3. The digital transformation of oral health care. Teledentistry and electronic commerce.

    Science.gov (United States)

    Bauer, J C; Brown, W T

    2001-02-01

    Health care is being changed dramatically by the marriage of computers and telecommunications. Implications for hospitals and physicians already have received extensive media attention, but comparatively little has been said about the impact of information technology on dentistry. This article illustrates how the digital transformation will likely affect dentists and their patients. Based on recent experiences of hospitals and medical practices, dentists can expect to encounter revolutionary changes as a result of the digital transformation. The Internet, the World Wide Web and other developments of the information revolution will redefine patient care, referral relationships, practice management, quality, professional organizations and competition. To respond proactively to the digital transformation of oral health care, dentists must become familiar with its technologies and concepts. They must learn what new information technology can do for them and their patients and then develop creative applications that promote the profession and their approaches to care.

  4. Coronary Arteries Segmentation Based on the 3D Discrete Wavelet Transform and 3D Neutrosophic Transform

    Directory of Open Access Journals (Sweden)

    Shuo-Tsung Chen

    2015-01-01

    Full Text Available Purpose. Most applications in the field of medical image processing require precise estimation. To improve the accuracy of segmentation, this study aimed to propose a novel segmentation method for coronary arteries to allow for the automatic and accurate detection of coronary pathologies. Methods. The proposed segmentation method included 2 parts. First, 3D region growing was applied to give the initial segmentation of coronary arteries. Next, the location of vessel information, HHH subband coefficients of the 3D DWT, was detected by the proposed vessel-texture discrimination algorithm. Based on the initial segmentation, 3D DWT integrated with the 3D neutrosophic transformation could accurately detect the coronary arteries. Results. Each subbranch of the segmented coronary arteries was segmented correctly by the proposed method. The obtained results are compared with those ground truth values obtained from the commercial software from GE Healthcare and the level-set method proposed by Yang et al., 2007. Results indicate that the proposed method is better in terms of efficiency analyzed. Conclusion. Based on the initial segmentation of coronary arteries obtained from 3D region growing, one-level 3D DWT and 3D neutrosophic transformation can be applied to detect coronary pathologies accurately.

  5. Coronary arteries segmentation based on the 3D discrete wavelet transform and 3D neutrosophic transform.

    Science.gov (United States)

    Chen, Shuo-Tsung; Wang, Tzung-Dau; Lee, Wen-Jeng; Huang, Tsai-Wei; Hung, Pei-Kai; Wei, Cheng-Yu; Chen, Chung-Ming; Kung, Woon-Man

    2015-01-01

    Most applications in the field of medical image processing require precise estimation. To improve the accuracy of segmentation, this study aimed to propose a novel segmentation method for coronary arteries to allow for the automatic and accurate detection of coronary pathologies. The proposed segmentation method included 2 parts. First, 3D region growing was applied to give the initial segmentation of coronary arteries. Next, the location of vessel information, HHH subband coefficients of the 3D DWT, was detected by the proposed vessel-texture discrimination algorithm. Based on the initial segmentation, 3D DWT integrated with the 3D neutrosophic transformation could accurately detect the coronary arteries. Each subbranch of the segmented coronary arteries was segmented correctly by the proposed method. The obtained results are compared with those ground truth values obtained from the commercial software from GE Healthcare and the level-set method proposed by Yang et al., 2007. Results indicate that the proposed method is better in terms of efficiency analyzed. Based on the initial segmentation of coronary arteries obtained from 3D region growing, one-level 3D DWT and 3D neutrosophic transformation can be applied to detect coronary pathologies accurately.

  6. E-Business Transformation: An Analysis Framework Based on Critical Organizational Dimensions

    Institute of Scientific and Technical Information of China (English)

    ZENG Qingfeng; CHEN Wenbo; HUANG Lihua

    2008-01-01

    In the era of Internet economics, e-business has become one of the most important strategic factors for enterprise development, so theoretical systems are needed to help enterprises develop e-business transformation strategies. A review of enterprise transformation theory identified five critical organization dimensions of e-business transformation, corporate strategy and vision transformation, organizational structure, product and market transformation, business process transformation, and corporate culture transformation. An e-business transformation process model was developed based on the five dimensions. This model can help enterprises to more effectively implement e-business transformation strategies.

  7. Modelling of Singapore's topographic transformation based on DEMs

    Science.gov (United States)

    Wang, Tao; Belle, Iris; Hassler, Uta

    2015-02-01

    Singapore's topography has been heavily transformed by industrialization and urbanization processes. To investigate topographic changes and evaluate soil mass flows, historical topographic maps of 1924 and 2012 were employed, and basic topographic features were vectorized. Digital elevation models (DEMs) for the two years were reconstructed based on vector features. Corresponding slope maps, a surface difference map and a scatter plot of elevation changes were generated and used to quantify and categorize the nature of the topographic transformation. The surface difference map is aggregated into five main categories of changes: (1) areas without significant height changes, (2) lowered-down areas where hill ranges were cut down, (3) raised-up areas where valleys and swamps were filled in, (4) reclaimed areas from the sea, and (5) new water-covered areas. Considering spatial proximity and configurations of different types of changes, topographic transformation can be differentiated as either creating inland flat areas or reclaiming new land from the sea. Typical topographic changes are discussed in the context of Singapore's urbanization processes. The two slope maps and elevation histograms show that generally, the topographic surface of Singapore has become flatter and lower since 1924. More than 89% of height changes have happened within a range of 20 m and 95% have been below 40 m. Because of differences in land surveying and map drawing methods, uncertainties and inaccuracies inherent in the 1924 topographic maps are discussed in detail. In this work, a modified version of a traditional scatter plot is used to present height transformation patterns intuitively. This method of deriving categorical maps of topographical changes from a surface difference map can be used in similar studies to qualitatively interpret transformation. Slope maps and histograms were also used jointly to reveal additional patterns of topographic change.

  8. The Bravyi-Kitaev transformation for quantum computation of electronic structure

    Science.gov (United States)

    Seeley, Jacob T.; Richard, Martin J.; Love, Peter J.

    2012-12-01

    Quantum simulation is an important application of future quantum computers with applications in quantum chemistry, condensed matter, and beyond. Quantum simulation of fermionic systems presents a specific challenge. The Jordan-Wigner transformation allows for representation of a fermionic operator by O(n) qubit operations. Here, we develop an alternative method of simulating fermions with qubits, first proposed by Bravyi and Kitaev [Ann. Phys. 298, 210 (2002), 10.1006/aphy.2002.6254; e-print arXiv:quant-ph/0003137v2], that reduces the simulation cost to O(log n) qubit operations for one fermionic operation. We apply this new Bravyi-Kitaev transformation to the task of simulating quantum chemical Hamiltonians, and give a detailed example for the simplest possible case of molecular hydrogen in a minimal basis. We show that the quantum circuit for simulating a single Trotter time step of the Bravyi-Kitaev derived Hamiltonian for H2 requires fewer gate applications than the equivalent circuit derived from the Jordan-Wigner transformation. Since the scaling of the Bravyi-Kitaev method is asymptotically better than the Jordan-Wigner method, this result for molecular hydrogen in a minimal basis demonstrates the superior efficiency of the Bravyi-Kitaev method for all quantum computations of electronic structure.

  9. High-temperature phase transformation in Cr added TiAl base alloy

    Energy Technology Data Exchange (ETDEWEB)

    Abe, E.; Niinobe, K.; Nobuki, M.; Nakamura, M.; Tsujimoto, T.

    1999-07-01

    The authors have investigated a microstructure evolution of a Ti-48Al-3.5Cr (in at.%) alloy at high-temperatures ({gt} 1,473K). In the alloy annealed at 1673K for 1.8ks, followed by air-cooling, a characteristic microstructure with a feathery fashion was uniformly formed. From a cooling-rate-controlling study, it was found that formation of the feathery structure is accomplished during continuous cooling from 1673K to 1573K, within the {alpha} + {gamma} two-phase region. Transmission electron microscopy revealed that the feathery structure is composed of lamellar colonies (5--10{micro}m) which are crystallographically tilted slightly (a few degree) with their neighbors. A surprising fact is that lamellae in each colony are mostly the {gamma} phase with few {alpha}{sub 2} phase less than 5% in volume. This suggests that the feathery structure is a metastable product and has not resulted from the {alpha} {r{underscore}arrow} {alpha} + {gamma} transformation above 1,573 K. Instead, the feathery structure formation should be attributed to the non-equilibrium {alpha} {r{underscore}arrow} {gamma} transformation which occurs at high-temperatures with a small degree of supercooling. The authors discuss this interesting phase transformation in terms of the {alpha} {r{underscore}arrow} {gamma} massive transformation, based on the continuous-cooling-transformation (CCT) diagram constructed for the present alloy.

  10. Weighted least squares phase unwrapping based on the wavelet transform

    Science.gov (United States)

    Chen, Jiafeng; Chen, Haiqin; Yang, Zhengang; Ren, Haixia

    2007-01-01

    The weighted least squares phase unwrapping algorithm is a robust and accurate method to solve phase unwrapping problem. This method usually leads to a large sparse linear equation system. Gauss-Seidel relaxation iterative method is usually used to solve this large linear equation. However, this method is not practical due to its extremely slow convergence. The multigrid method is an efficient algorithm to improve convergence rate. However, this method needs an additional weight restriction operator which is very complicated. For this reason, the multiresolution analysis method based on the wavelet transform is proposed. By applying the wavelet transform, the original system is decomposed into its coarse and fine resolution levels and an equivalent equation system with better convergence condition can be obtained. Fast convergence in separate coarse resolution levels speeds up the overall system convergence rate. The simulated experiment shows that the proposed method converges faster and provides better result than the multigrid method.

  11. Towards discrete wavelet transform-based human activity recognition

    Science.gov (United States)

    Khare, Manish; Jeon, Moongu

    2017-06-01

    Providing accurate recognition of human activities is a challenging problem for visual surveillance applications. In this paper, we present a simple and efficient algorithm for human activity recognition based on a wavelet transform. We adopt discrete wavelet transform (DWT) coefficients as a feature of human objects to obtain advantages of its multiresolution approach. The proposed method is tested on multiple levels of DWT. Experiments are carried out on different standard action datasets including KTH and i3D Post. The proposed method is compared with other state-of-the-art methods in terms of different quantitative performance measures. The proposed method is found to have better recognition accuracy in comparison to the state-of-the-art methods.

  12. Clone Detection for Graph-Based Model Transformation Languages

    DEFF Research Database (Denmark)

    Strüber, Daniel; Plöger, Jennifer; Acretoaie, Vlad

    2016-01-01

    and analytical quality assurance. From these use cases, we derive a set of key requirements. We describe our customization of existing model clone detection techniques allowing us to address these requirements. Finally, we provide an experimental evaluation, indicating that our customization of ConQAT, one......Cloning is a convenient mechanism to enable reuse across and within software artifacts. On the downside, it is also a practice related to significant long-term maintainability impediments, thus generating a need to identify clones in affected artifacts. A large variety of clone detection techniques...... has been proposed for programming and modeling languages; yet no specific ones have emerged for model transformation languages. In this paper, we explore clone detection for graph-based model transformation languages. We introduce potential use cases for such techniques in the context of constructive...

  13. Study of Dielectric Breakdown Performance of Transformer Oil Based Magnetic Nanofluids

    Directory of Open Access Journals (Sweden)

    Yuzhen Lv

    2017-07-01

    Full Text Available Research on the transformer oil-based nanofluids (NFs has been raised expeditiously over the past decade. Although, there is discrepancy in the stated results and inadequate understanding of the mechanisms of improvement of dielectric nanofluids, these nanofluids have emerged as a potential substitute of mineral oils as insulating and heat removal fluids for high voltage equipment. The transformer oil (TO based magnetic fluids (ferrofluids may be regarded as the posterity insulation fluids as they propose inspiring unique prospectus to improve dielectric breakdown strength, as well as heat transfer efficiency, as compared to pure transformer oils. In this work, transformer oil-based magnetic nanofluids (MNFs are prepared by dispersal of Fe3O4 nanoparticles (MNPs into mineral oil as base oil, with various NPs loading from 5 to 80% w/v. The lightning impulse breakdown voltages (BDV measurement was conducted in accordance with IEC 60897 by using needle to sphere electrodes geometry. The test results showed that dispersion of magnetic NPs may improve the insulation strength of MO. With the increment of NPs concentrations, the positive lightning impulse (LI breakdown strength of TO is first raised, up to the highest value at 40% loading, and then tends to decrease at higher concentrations. The outcomes of negative LI breakdown showed that BDV of MNFs, with numerous loadings, were inferior to the breakdown strength of pure MO. The 40% concentration of nanoparticles (optimum concentration was selected, and positive and negative LI breakdown strength was also further studied at different sizes (10 nm, 20 nm, 30 nm and 40 nm of NPs and different electrode gap distances. Augmentation in the BDV of the ferrofluids (FFs is primarily because of dielectric and magnetic features of Fe3O4 nanoaprticles, which act as electron scavengers and decrease the rate of free electrons produced in the ionization process. Research challenges and technical difficulties

  14. PLZT-based photovoltaic Piezoelectric Transformer with light feedback

    Energy Technology Data Exchange (ETDEWEB)

    Kozielski, L [University of Silesia, Dep. Materials Sc, 2, Sniezna St. Sosnowiec, 41-200 Poland (Poland); Adamczyk, M [University of Silesia, Institute Phys., 4, Uniwersytecka St. Katowice, 40-007 Poland (Poland); Erhart, J, E-mail: lucjan.kozielski@us.edu.pl [Technical University of Liberec, Studencka St. 2, CZ-461 17 Liberec (Czech Republic)

    2011-10-29

    Piezoelectric Transformer (PT) converts an electrical AC input voltage into ultrasonic vibrations and reconverts back to an output as AC voltage. Hard lead zirconate titanate (PZT) ceramics is typically used for fabrications of such devices. In case of lanthaniun ion La{sup 3+} addition in PZT solid solution we can achieve piezoelectric ceramics with good transparency exhibiting both optical Pockels and Kerr effects. Values of these coefficients in the PLZT system are much bigger than in LiNbO{sub 3} or SBN single crystals. Among the various PLZT compositions 8/65/35, near the morphotropic boundary, exhibit large electrooptic effect and thus have found applications in light shutters and displays. In the present study we have investigated radial mode piezoelectric transformer based on optically transparent PLZT8/65/35 ceramics. The effect of the UV light generated photovoltage and photostriction on the efficiency and voltage step-up ratio of piezoelectric transformer have been demonstrated. Novel functions of this device is proposed by superimposing two sophistically coupled effects of piezoelectricity and photostriction.

  15. Electron irradiation effect on the reverse phase transformation temperatures in TiNi shape memory alloy thin films

    International Nuclear Information System (INIS)

    Wang, Z.G.; Zu, X.T.; Fu, Y.Q.; Zhu, S.; Wang, L.M.

    2005-01-01

    In this work, Ti-Ni shape memory alloy thin films were irradiated by 1.7 MeV electron with three types of fluences: 4 x 10 20 , 7 x 10 20 and 1 x 10 21 /m 2 . The influence of electron irradiation on the transformation behavior of the TiNi thin films were investigated by differential scanning calorimetry. The transformation temperatures A s and A f shifted to higher temperature after electron irradiation, the martensite was stabilized. The electron irradiation effect can be easily eliminated by one thermal cycle. The shifts of the transformation temperatures can be explained from the change of potential energy barrier and coherency energy between parent phase and martensite after irradiation

  16. Multi-band Image Registration Method Based on Fourier Transform

    Institute of Scientific and Technical Information of China (English)

    庹红娅; 刘允才

    2004-01-01

    This paper presented a registration method based on Fourier transform for multi-band images which is involved in translation and small rotation. Although different band images differ a lot in the intensity and features,they contain certain common information which we can exploit. A model was given that the multi-band images have linear correlations under the least-square sense. It is proved that the coefficients have no effect on the registration progress if two images have linear correlations. Finally, the steps of the registration method were proposed. The experiments show that the model is reasonable and the results are satisfying.

  17. Six transformer based asymmetrical embedded Z-source inverters

    DEFF Research Database (Denmark)

    Wei, Mo; Poh Chiang, Loh; Chi, Jin

    2013-01-01

    Embedded/Asymmetrical embedded Z-source inverters were proposed to maintain smooth input current/voltage across the dc source and within the impedance network, remain the shoot-through feature used to boost up the dc-link voltage without adding bulky filter at input side. This paper introduces a ...... a class of transformer based asymmetrical embedded Z-source inverters which keep the smooth input current and voltage while achieving enhanced voltage boost capability. The presented inverters are verified by laboratory prototypes experimentally....

  18. A difference tracking algorithm based on discrete sine transform

    Science.gov (United States)

    Liu, HaoPeng; Yao, Yong; Lei, HeBing; Wu, HaoKun

    2018-04-01

    Target tracking is an important field of computer vision. The template matching tracking algorithm based on squared difference matching (SSD) and standard correlation coefficient (NCC) matching is very sensitive to the gray change of image. When the brightness or gray change, the tracking algorithm will be affected by high-frequency information. Tracking accuracy is reduced, resulting in loss of tracking target. In this paper, a differential tracking algorithm based on discrete sine transform is proposed to reduce the influence of image gray or brightness change. The algorithm that combines the discrete sine transform and the difference algorithm maps the target image into a image digital sequence. The Kalman filter predicts the target position. Using the Hamming distance determines the degree of similarity between the target and the template. The window closest to the template is determined the target to be tracked. The target to be tracked updates the template. Based on the above achieve target tracking. The algorithm is tested in this paper. Compared with SSD and NCC template matching algorithms, the algorithm tracks target stably when image gray or brightness change. And the tracking speed can meet the read-time requirement.

  19. Transforming paper-based assessment forms to a digital format

    DEFF Research Database (Denmark)

    Jonasen, Tanja Svarre; Lunn, Tine Bieber; Helle, Tina

    2017-01-01

    Background: The aim of this paper is to provide the reader with an overall impression of the stepwise user-centred design approach including the specific methods used and lessons learned when transforming paper-based assessment forms into a prototype app, taking the Housing Enabler as an example....... Results: The design iterations resulted in the development of a Housing Enabler prototype app. The prototype app has several features and options that are new compared with the original paper-based Housing Enabler assessment form. These new features include a user friendly overview of the assessment form......; easy navigation by swiping back and forth between items; onsite data analysis; and ranking of the accessibility score, photo documentation and a data export facility. Conclusion: Based on the presented stepwise approach, a high-fidelity Housing Enabler prototype app was successfully developed...

  20. Investigation of the aluminium-aluminium oxide reversible transformation as observed by hot stage electron microscopy.

    Science.gov (United States)

    Grove, C. A.; Judd, G.; Ansell, G. S.

    1972-01-01

    Thin foils of high purity aluminium and an Al-Al2O3 SAP type of alloy were oxidised in a specially designed hot stage specimen chamber in an electron microscope. Below 450 C, amorphous aluminium oxide formed on the foil surface and was first detectable at foil edges, holes, and pits. Islands of aluminium then nucleated in this amorphous oxide. The aluminium islands displayed either a lateral growth with eventual coalescence with other islands, or a reoxidation process which caused the islands to disappear. The aluminium island formation was determined to be related to the presence of the electron beam. A mechanism based upon electron charging due to the electron beam was proposed to explain the nucleation, growth, coalescence, disappearance, and geometry of the aluminium islands.

  1. Transforming narratives into educational tools: the collaborative development of a transformative learning tool based on Nicaraguan adolescents' creative writing about intimate partner violence.

    Science.gov (United States)

    Singleton, Robyn; Picado Araúz, María de la Paz; Trocin, Kathleen; Winskell, Kate

    2017-01-01

    The use of narrative has become increasingly popular in the public health, community development, and education fields. Via emotionally engaging plotlines with authentic, captivating characters, stories provide an opportunity for participants to be carried away imaginatively into the characters' world while connecting the story with their own lived experiences. Stories have been highlighted as valuable tools in transformative learning. However, little published literature exists demonstrating applications of stories in group-based transformative learning curricula. This paper describes the creation of a narrative-based transformative learning tool based on an analysis of Nicaraguan adolescents' meaning-making around intimate partner violence (IPV) in their creative narratives. In collaboration with a Nicaraguan organization, US researchers analyzed a sample of narratives ( n = 55; 16 male-authored, 39 female-authored) on IPV submitted to a 2014 scriptwriting competition by adolescents aged 15-19. The data were particularly timely in that they responded to a new law protecting victims of gender-based violence, Law 779, and contradicted social-conservative claims that the Law 779 destroys family unity. We incorporated results from this analysis into the creation of the transformative learning tool, separated into thematic sections. The tool's sections (which comprise one story and three corresponding activities) aim to facilitate critical reflection, interpersonal dialogue, and self- and collective efficacy for social action around the following themes derived from the analysis: IPV and social support; IPV and romantic love; masculinity; warning signs of IPV; and sexual abuse. As a collaboration between a public health research team based at a US university and a Nicaraguan community-based organization, it demonstrates the potential in the age of increasingly smooth electronic communication for novel community-university partnerships to facilitate the development of

  2. Approximation for discrete Fourier transform and application in study of three-dimensional interacting electron gas.

    Science.gov (United States)

    Yan, Xin-Zhong

    2011-07-01

    The discrete Fourier transform is approximated by summing over part of the terms with corresponding weights. The approximation reduces significantly the requirement for computer memory storage and enhances the numerical computation efficiency with several orders without losing accuracy. As an example, we apply the algorithm to study the three-dimensional interacting electron gas under the renormalized-ring-diagram approximation where the Green's function needs to be self-consistently solved. We present the results for the chemical potential, compressibility, free energy, entropy, and specific heat of the system. The ground-state energy obtained by the present calculation is compared with the existing results of Monte Carlo simulation and random-phase approximation.

  3. Double-resolution electron holography with simple Fourier transform of fringe-shifted holograms.

    Science.gov (United States)

    Volkov, V V; Han, M G; Zhu, Y

    2013-11-01

    We propose a fringe-shifting holographic method with an appropriate image wave recovery algorithm leading to exact solution of holographic equations. With this new method the complex object image wave recovered from holograms appears to have much less traditional artifacts caused by the autocorrelation band present practically in all Fourier transformed holograms. The new analytical solutions make possible a double-resolution electron holography free from autocorrelation band artifacts and thus push the limits for phase resolution. The new image wave recovery algorithm uses a popular Fourier solution of the side band-pass filter technique, while the fringe-shifting holographic method is simple to implement in practice. Published by Elsevier B.V.

  4. Electronic structure of Fe-based superconductors

    Indian Academy of Sciences (India)

    Abstract. Fe-based superconductors have drawn much attention during the last decade due to the presence of superconductivity in materials containing the magnetic element, Fe, and the coexistence of superconductivity and magnetism. Extensive study of the electronic structure of these systems suggested the dominant ...

  5. Electronic structure of Fe-based superconductors

    Indian Academy of Sciences (India)

    2015-05-29

    May 29, 2015 ... Fe-based superconductors have drawn much attention during the last decade due to the presence of superconductivity in materials containing the magnetic element, Fe, and the coexistence of superconductivity and magnetism. Extensive study of the electronic structure of these systems suggested the ...

  6. An accurate on-site calibration system for electronic voltage transformers using a standard capacitor

    Science.gov (United States)

    Hu, Chen; Chen, Mian-zhou; Li, Hong-bin; Zhang, Zhu; Jiao, Yang; Shao, Haiming

    2018-05-01

    Ordinarily electronic voltage transformers (EVTs) are calibrated off-line and the calibration procedure requires complex switching operations, which will influence the reliability of the power grid and induce large economic losses. To overcome this problem, this paper investigates a 110 kV on-site calibration system for EVTs, including a standard channel, a calibrated channel and a PC equipped with the LabView environment. The standard channel employs a standard capacitor and an analogue integrating circuit to reconstruct the primary voltage signal. Moreover, an adaptive full-phase discrete Fourier transform (DFT) algorithm is proposed to extract electrical parameters. The algorithm involves the process of extracting the frequency of the grid, adjusting the operation points, and calculating the results using DFT. In addition, an insulated automatic lifting device is designed to realize the live connection of the standard capacitor, which is driven by a wireless remote controller. A performance test of the capacitor verifies the accurateness of the standard capacitor. A system calibration test shows that the system ratio error is less than 0.04% and the phase error is below 2‧, which meets the requirement of the 0.2 accuracy class. Finally, the developed calibration system was used in a substation, and the field test data validates the availability of the system.

  7. Transformations of gold nanoparticles investigated using variable temperature high-resolution transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Young, N.P. [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Huis, M.A. van; Zandbergen, H.W. [Kavli Institute of Nanoscience, Delft University of Technolgy, Lorentzweg 1, NL-2628CJ, Delft, The Netherlands. (Netherlands); Xu, H. [Department of Geology and Geophysics, and Materials Science Program, University of Wisconsin-Madison, Madison, WI (United States); Kirkland, A.I., E-mail: angus.kirkland@materials.ox.ac.uk [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom)

    2010-04-15

    Recently designed advanced in-situ specimen holders for transmission electron microscopy (TEM) have been used in studies of gold nanoparticles. We report results of variable temperature TEM experiments in which structural transformations have been correlated with specimen temperature, allowing general trends to be identified. Transformation to a decahedral morphology for particles in the size range 5-12 nm was observed for the majority of particles regardless of their initial structure. Following in-situ annealing, decahedra were found to be stable at room temperature, confirming this as the equilibrium morphology, in agreement with recently calculated phase diagrams. Other transitions at low temperature in addition to surface roughening have also been observed and correlated with the same nanoscale phase diagram. Investigations of gold particles at high temperature have revealed evidence for co-existing solid and liquid phases. Overall, these results are important in a more precise understanding of the structure and action of catalytic gold nanoparticles and in the experimental verification of theoretical calculations.

  8. TP-model transformation-based-control design frameworks

    CERN Document Server

    Baranyi, Péter

    2016-01-01

    This book covers new aspects and frameworks of control, design, and optimization based on the TP model transformation and its various extensions. The author outlines the three main steps of polytopic and LMI based control design: 1) development of the qLPV state-space model, 2) generation of the polytopic model; and 3) application of LMI to derive controller and observer. He goes on to describe why literature has extensively studied LMI design, but has not focused much on the second step, in part because the generation and manipulation of the polytopic form was not tractable in many cases. The author then shows how the TP model transformation facilitates this second step and hence reveals new directions, leading to powerful design procedures and the formulation of new questions. The chapters of this book, and the complex dynamical control tasks which they cover, are organized so as to present and analyze the beneficial aspect of the family of approaches (control, design, and optimization). Additionally, the b...

  9. Evaluation of Rule-based Modularization in Model Transformation Languages illustrated with ATL

    NARCIS (Netherlands)

    Ivanov, Ivan; van den Berg, Klaas; Jouault, Frédéric

    This paper studies ways for modularizing transformation definitions in current rule-based model transformation languages. Two scenarios are shown in which the modular units are identified on the base of the relations between source and target metamodels and on the base of generic transformation

  10. Wiener discrete cosine transform-based image filtering

    Science.gov (United States)

    Pogrebnyak, Oleksiy; Lukin, Vladimir V.

    2012-10-01

    A classical problem of additive white (spatially uncorrelated) Gaussian noise suppression in grayscale images is considered. The main attention is paid to discrete cosine transform (DCT)-based denoising, in particular, to image processing in blocks of a limited size. The efficiency of DCT-based image filtering with hard thresholding is studied for different sizes of overlapped blocks. A multiscale approach that aggregates the outputs of DCT filters having different overlapped block sizes is proposed. Later, a two-stage denoising procedure that presumes the use of the multiscale DCT-based filtering with hard thresholding at the first stage and a multiscale Wiener DCT-based filtering at the second stage is proposed and tested. The efficiency of the proposed multiscale DCT-based filtering is compared to the state-of-the-art block-matching and three-dimensional filter. Next, the potentially reachable multiscale filtering efficiency in terms of output mean square error (MSE) is studied. The obtained results are of the same order as those obtained by Chatterjee's approach based on nonlocal patch processing. It is shown that the ideal Wiener DCT-based filter potential is usually higher when noise variance is high.

  11. Data base systems in electronic design engineering

    Science.gov (United States)

    Williams, D.

    1980-01-01

    The concepts of an integrated design data base system (DBMS) as it might apply to an electronic design company are discussed. Data elements of documentation, project specifications, project tracking, firmware, software, electronic and mechanical design can be integrated and managed through a single DBMS. Combining the attributes of a DBMS data handler with specialized systems and functional data can provide users with maximum flexibility, reduced redundancy, and increased overall systems performance. Although some system overhead is lost due to redundancy in transitory data, it is believed the combination of the two data types is advisable rather than trying to do all data handling through a single DBMS.

  12. Catalytic Transformation of Ethylbenzene over Y-Zeolite-based Catalysts

    KAUST Repository

    Al-Khattaf, Sulaiman

    2008-11-19

    Catalytic transformation of ethylbenzene (EB) has been investigated over ultrastable Y (USY)-zeolite-based catalysts in a novel riser simulator at different operating conditions. The effect of reaction conditions on EB conversion is reported. The USY catalyst (FCC-Y) was modified by steaming to form a significantly lower acidity catalyst (FCC-SY). The current study shows that the FCC-SY catalyst favors EB disproportionation more than cracking. A comparison has been made between the results of EB conversion over the lowly acidic catalyst (FCC-SY) and the highly acidic catalyst (FCC-Y) under identical conditions. It was observed that increase in catalyst acidity favored cracking of EB at the expense of disproportionation. Kinetic parameters for EB disappearance during disproportionation reaction over the FCC-SY catalyst were calculated using the catalyst activity decay function based on time on stream (TOS). © 2008 American Chemical Society.

  13. SPARQL Query Re-writing Using Partonomy Based Transformation Rules

    Science.gov (United States)

    Jain, Prateek; Yeh, Peter Z.; Verma, Kunal; Henson, Cory A.; Sheth, Amit P.

    Often the information present in a spatial knowledge base is represented at a different level of granularity and abstraction than the query constraints. For querying ontology's containing spatial information, the precise relationships between spatial entities has to be specified in the basic graph pattern of SPARQL query which can result in long and complex queries. We present a novel approach to help users intuitively write SPARQL queries to query spatial data, rather than relying on knowledge of the ontology structure. Our framework re-writes queries, using transformation rules to exploit part-whole relations between geographical entities to address the mismatches between query constraints and knowledge base. Our experiments were performed on completely third party datasets and queries. Evaluations were performed on Geonames dataset using questions from National Geographic Bee serialized into SPARQL and British Administrative Geography Ontology using questions from a popular trivia website. These experiments demonstrate high precision in retrieval of results and ease in writing queries.

  14. Structural Transformations in Two-Dimensional Transition-Metal Dichalcogenide MoS2 under an Electron Beam

    DEFF Research Database (Denmark)

    Kretschmer, Silvan; Komsa, Hannu-Pekka; Bøggild, Peter

    2017-01-01

    prismatic H phase to the metallic octahedral T phase in 2D MoS2 have been induced by electron irradiation [Nat. Nanotech. 2014, 9, 391], but the mechanism of the transformations remains elusive. Using density functional theory calculations, we study the energetics of the stable and metastable phases of 2D...... MoS2 when additional charge, mechanical strain, and vacancies are present. We also investigate the role of finite temperatures, which appear to be critical for the transformations. On the basis of the results of our calculations, we propose an explanation for the beam-induced transformations, which...... development and optimization of electron-beam-mediated engineering of the atomic structure and electronic properties of 2D TMDs with subnanometer resolution....

  15. Communication: Electron ionization of DNA bases

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, M. A.; Krishnakumar, E., E-mail: ekkumar@tifr.res.in

    2016-04-28

    No reliable experimental data exist for the partial and total electron ionization cross sections for DNA bases, which are very crucial for modeling radiation damage in genetic material of living cell. We have measured a complete set of absolute partial electron ionization cross sections up to 500 eV for DNA bases for the first time by using the relative flow technique. These partial cross sections are summed to obtain total ion cross sections for all the four bases and are compared with the existing theoretical calculations and the only set of measured absolute cross sections. Our measurements clearly resolve the existing discrepancy between the theoretical and experimental results, thereby providing for the first time reliable numbers for partial and total ion cross sections for these molecules. The results on fragmentation analysis of adenine supports the theory of its formation in space.

  16. Atomic and electronic structure transformations of silver nanoparticles under rapid cooling conditions.

    Science.gov (United States)

    Lobato, I; Rojas, J; Landauro, C V; Torres, J

    2009-02-04

    The structural evolution and dynamics of silver nanodrops Ag(2869) (4.4 nm in diameter) under rapid cooling conditions have been studied by means of molecular dynamics simulations and electronic density of state calculations. The interaction of silver atoms is modelled by a tight-binding semiempirical interatomic potential proposed by Cleri and Rosato. The pair correlation functions and the pair analysis technique are used to reveal the structural transition in the process of solidification. It is shown that Ag nanoparticles evolve into different nanostructures under different cooling processes. At a cooling rate of 1.5625 × 10(13) K s(-1) the nanoparticles preserve an amorphous-like structure containing a large amount of 1551 and 1541 pairs which correspond to icosahedral symmetry. For a lower cooling rate (1.5625 × 10(12) K s(-1)), the nanoparticles transform into a crystal-like structure consisting mainly of 1421 and 1422 pairs which correspond to the face centred cubic and hexagonal close packed structures, respectively. The variations of the electronic density of states for the differently cooled nanoparticles are small, but in correspondence with the structural changes.

  17. High resolution electron microscope study of the omega transformation in Zr--Nb alloys

    International Nuclear Information System (INIS)

    Chang, A.L.J.; Sass, S.L.; Krakow, W.

    1976-01-01

    High resolution direct lattice imaging and dark field electron microscopy were used to examine the omega phase transformation in Zr--Nb alloys. Direct lattice imaging demonstrated the existence of subvariants within an omega variant. The existence of an ordered sequence of subvariants, which is the basic premise of recent diffuse intensity calculations which seek to explain diffuse diffraction observations in high Nb content alloys, could not be checked because of the small size of the omega regions. In the low Nb content alloys dark field electron microscopy was used to show that the ω phase consists of large domains (100 to 200 A dia) the interior of which contains features that are 3 to 6 A dia. As the Nb content is increased the omega domains decrease in size until only 3 to 5 A images are observed in alloys containing 15 wt. percent Nb or more. The isolated images are present over the range of composition from 8 to 30 wt. percent Nb. Time sequence dark field micrographs show that these small images change with time. The diffuse ω reflections are believed due in part to the existence of a (111) linear detect, consisting of groups of (111) rows of atoms which are displaced from bcc to ω positions for short periods of time

  18. Double-resolution electron holography with simple Fourier transform of fringe-shifted holograms

    International Nuclear Information System (INIS)

    Volkov, V.V.; Han, M.G.; Zhu, Y.

    2013-01-01

    We propose a fringe-shifting holographic method with an appropriate image wave recovery algorithm leading to exact solution of holographic equations. With this new method the complex object image wave recovered from holograms appears to have much less traditional artifacts caused by the autocorrelation band present practically in all Fourier transformed holograms. The new analytical solutions make possible a double-resolution electron holography free from autocorrelation band artifacts and thus push the limits for phase resolution. The new image wave recovery algorithm uses a popular Fourier solution of the side band-pass filter technique, while the fringe-shifting holographic method is simple to implement in practice. - Highlights: • We propose a fringe-shifting holographic method simple enough for practical implementations. • Our new image-wave-recovery algorithm follows from exact solution of holographic equations. • With autocorrelation band removal from holograms it is possible to achieve double-resolution electron holography data free from several commonly known artifacts. • The new fringe-shifting method can reach an image wave resolution close to single fringe spacing

  19. Double-resolution electron holography with simple Fourier transform of fringe-shifted holograms

    Energy Technology Data Exchange (ETDEWEB)

    Volkov, V.V., E-mail: volkov@bnl.gov; Han, M.G.; Zhu, Y.

    2013-11-15

    We propose a fringe-shifting holographic method with an appropriate image wave recovery algorithm leading to exact solution of holographic equations. With this new method the complex object image wave recovered from holograms appears to have much less traditional artifacts caused by the autocorrelation band present practically in all Fourier transformed holograms. The new analytical solutions make possible a double-resolution electron holography free from autocorrelation band artifacts and thus push the limits for phase resolution. The new image wave recovery algorithm uses a popular Fourier solution of the side band-pass filter technique, while the fringe-shifting holographic method is simple to implement in practice. - Highlights: • We propose a fringe-shifting holographic method simple enough for practical implementations. • Our new image-wave-recovery algorithm follows from exact solution of holographic equations. • With autocorrelation band removal from holograms it is possible to achieve double-resolution electron holography data free from several commonly known artifacts. • The new fringe-shifting method can reach an image wave resolution close to single fringe spacing.

  20. Transformation of methano[60]fullerenes in dihydrofullerofuranes induced by electron transfer

    International Nuclear Information System (INIS)

    Yanilkin, V.V.; Toropchina, A.V.; Morozov, V.I.; Nastapova, N.V.; Gubskaya, V.P.; Sibgatullina, F.G.; Azancheev, N.M.; Efremov, Yu.Ya.; Nuretdinov, I.A.

    2004-01-01

    The electrochemical reduction of methano[60]fullerenes (61-acetyl-61-(diethoxyphosphoryl)methano-60-fullerene 1, 61-acetyl-61-(diisopropoxyphosphoryl)methano-60-fullerene 2, 61-(2,2-diethoxyacetyl)-61-(diethoxy-phosphoryl)methano-60-fullerene 3, 61-phenyl-61-(1,2-dioxo-3,3-dimethyl-buthyl)methano-60-fullerene 4) in o-dichlorobenzene-DMF (3:1 v/v)/0.1 M Bu 4 NBF 4 on a glass-carbon electrode proceeds in a few steps. The reversible transfer of the first electron results in the formation of radical anions registered by ESR method. The subsequent reduction proceeds differently because of the various stability of anionic intermediates. The radical anions of the methanofullerenes 3 and 4 are less stable than the radical anions of compounds 1 and 2 and less stable than the radical anions of methanofullerenes, which contain an ester and/or a phosphonate group. The opening of a cyclopropane ring occurs during the stage of the formation of radical trianions of methanofullerenes 1, 2. The same process for compounds 3, 4 proceeds slowly in radical anions and fast in dianions. The opening of cyclopropane ring for all compounds is not accompanied by the elimination of methanogroup and results in the formation of dihydrofullerenofurane derivatives. The transformation of methanofullerene 3 induced by single electron transfer proceeds via a chain reaction mechanism

  1. Electron spin transition causing structure transformations of earth's interiors under high pressure

    Science.gov (United States)

    Yamanaka, T.; Kyono, A.; Kharlamova, S.; Alp, E.; Bi, W.; Mao, H.

    2012-12-01

    To elucidate the correlation between structure transitions and spin state is one of the crucial problems for understanding the geophysical properties of earth interiors under high pressure. High-pressure studies of iron bearing spinels attract extensive attention in order to understand strong electronic correlation such as the charge transfer, electron hopping, electron high-low spin transition, Jahn-Teller distortion and charge disproponation in the lower mantle or subduction zone [1]. Experiment Structure transitions of Fe3-xSixO4, Fe3-xTixO4 Fe3-xCrxO4 spinel solid solution have been investigated at high pressure up to 60 GPa by single crystal and powder diffraction studies using synchrotron radiation with diamond anvil cell. X-ray emission experiment (XES) at high pressure proved the spin transition of Fe-Kβ from high spin (HS) to intermediate spin state (IS) or low spin state (LS). Mössbauer experiment and Raman spectra study have been also conducted for deformation analysis of Fe site and confirmation of the configuration change of Fe atoms. Jahn-Teller effect A cubic-to-tetragonal transition under pressure was induced by Jahn-Teller effect of IVFe2+ (3d6) in the tetrahedral site of Fe2TiO4 and FeCr2O4, providing the transformation from 43m (Td) to 42m (D2d). Tetragonal phase is formed by the degeneracy of e orbital of Fe2+ ion. Their c/a ratios are c/adisordered in the M2 site. At pressures above 53 GPa, Fe2TiO4 structure further transforms to Pmma. This structure change results in the order-disorder transition [2]. New structure of Fe2SiO4 The spin transition exerts an influence to Fe2SiO4 spinel structure and triggers two distinct curves of the lattice constant in the spinel phase. The reversible structure transition from cubic to pseudo-rhombohedral phase was observed at about 45 GPa. This transition is induced by the 20% shrinkage of ionic radius of VIFe2+at the low sin state. Laser heating experiment at 1500 K has confirmed the decomposition from the

  2. Design and Implementation of GSM Based Transformer Phase ...

    African Journals Online (AJOL)

    In this work, the design and implementation of a transformer phase monitoring system, which continuously check for blown fuses on each phases of the distribution transformer was carried out. The system promptly reports any transformer with blown J&P fuse via a preprogrammed SMS which will state the location of the ...

  3. Low-Temperature Electron Beam-Induced Transformations of Cesium Lead Halide Perovskite Nanocrystals

    Science.gov (United States)

    2017-01-01

    Cesium lead halide perovskite (CsPbX3, with X = Br, Cl, I) nanocrystals have been found to undergo severe modifications under the high-energy electron beam irradiation of a transmission electron microscope (80/200 keV). In particular, in our previous work, together with halogen desorption, Pb2+ ions were found to be reduced to Pb0 and then diffused to form lead nanoparticles at temperatures above −40 °C. Here, we present a detailed irradiation study of CsPbBr3 nanocrystals at temperatures below −40 °C, a range in which the diffusion of Pb0 atoms/clusters is drastically suppressed. Under these conditions, the irradiation instead induces the nucleation of randomly oriented CsBr, CsPb, and PbBr2 crystalline domains. In addition to the Br desorption, which accompanies Pb2+ reduction at all the temperatures, Br is also desorbed from the CsBr and PbBr2 domains at low temperatures, leading to a more pronounced Br loss, thus the final products are mainly composed of Cs and Pb. The overall transformation involves the creation of voids, which coalesce upon further exposure, as demonstrated in both nanosheets and nanocuboids. Our results show that although low temperatures hinder the formation of Pb nanoparticles in CsPbBr3 nanocrystals when irradiated, the nanocrystals are nevertheless unstable. Consequently, we suggest that an optimum combination of temperature range, electron energy, and dose rate needs to be carefully chosen for the characterization of halide perovskite nanocrystals to minimize both the Pb nanoparticle formation and the structural decomposition. PMID:28983524

  4. Automated crystallographic ligand building using the medial axis transform of an electron-density isosurface.

    Science.gov (United States)

    Aishima, Jun; Russel, Daniel S; Guibas, Leonidas J; Adams, Paul D; Brunger, Axel T

    2005-10-01

    Automatic fitting methods that build molecules into electron-density maps usually fail below 3.5 A resolution. As a first step towards addressing this problem, an algorithm has been developed using an approximation of the medial axis to simplify an electron-density isosurface. This approximation captures the central axis of the isosurface with a graph which is then matched against a graph of the molecular model. One of the first applications of the medial axis to X-ray crystallography is presented here. When applied to ligand fitting, the method performs at least as well as methods based on selecting peaks in electron-density maps. Generalization of the method to recognition of common features across multiple contour levels could lead to powerful automatic fitting methods that perform well even at low resolution.

  5. An FPGA-Based Electronic Cochlea

    Directory of Open Access Journals (Sweden)

    M. P. Leong

    2003-06-01

    Full Text Available A module generator which can produce an FPGA-based implementation of an electronic cochlea filter with arbitrary precision is presented. Although hardware implementations of electronic cochlea models have traditionally used analog VLSI as the implementation medium due to their small area, high speed, and low power consumption, FPGA-based implementations offer shorter design times, improved dynamic range, higher accuracy, and a simpler computer interface. The tool presented takes filter coefficients as input and produces a synthesizable VHDL description of an application-optimized design as output. Furthermore, the tool can use simulation test vectors in order to determine the appropriate scaling of the fixed point precision parameters for each filter. The resulting model can be used as an accelerator for research in audition or as the front-end for embedded auditory signal processing systems. The application of this module generator to a real-time cochleagram display is also presented.

  6. Grating geophone signal processing based on wavelet transform

    Science.gov (United States)

    Li, Shuqing; Zhang, Huan; Tao, Zhifei

    2008-12-01

    Grating digital geophone is designed based on grating measurement technique benefiting averaging-error effect and wide dynamic range to improve weak signal detected precision. This paper introduced the principle of grating digital geophone and its post signal processing system. The signal acquisition circuit use Atmega 32 chip as core part and display the waveform on the Labwindows through the RS232 data link. Wavelet transform is adopted this paper to filter the grating digital geophone' output signal since the signal is unstable. This data processing method is compared with the FIR filter that widespread use in current domestic. The result indicates that the wavelet algorithm has more advantages and the SNR of seismic signal improve obviously.

  7. Parallel processing approach to transform-based image coding

    Science.gov (United States)

    Normile, James O.; Wright, Dan; Chu, Ken; Yeh, Chia L.

    1991-06-01

    This paper describes a flexible parallel processing architecture designed for use in real time video processing. The system consists of floating point DSP processors connected to each other via fast serial links, each processor has access to a globally shared memory. A multiple bus architecture in combination with a dual ported memory allows communication with a host control processor. The system has been applied to prototyping of video compression and decompression algorithms. The decomposition of transform based algorithms for decompression into a form suitable for parallel processing is described. A technique for automatic load balancing among the processors is developed and discussed, results ar presented with image statistics and data rates. Finally techniques for accelerating the system throughput are analyzed and results from the application of one such modification described.

  8. Digital differential confocal microscopy based on spatial shift transformation.

    Science.gov (United States)

    Liu, J; Wang, Y; Liu, C; Wilson, T; Wang, H; Tan, J

    2014-11-01

    Differential confocal microscopy is a particularly powerful surface profilometry technique in industrial metrology due to its high axial sensitivity and insensitivity to noise. However, the practical implementation of the technique requires the accurate positioning of point detectors in three-dimensions. We describe a simple alternative based on spatial transformation of a through-focus series of images obtained from a homemade beam scanning confocal microscope. This digital differential confocal microscopy approach is described and compared with the traditional Differential confocal microscopy approach. The ease of use of the digital differential confocal microscopy system is illustrated by performing measurements on a 3D standard specimen. © 2014 The Authors Journal of Microscopy © 2014 Royal Microscopical Society.

  9. A New Quantum Watermarking Based on Quantum Wavelet Transforms

    International Nuclear Information System (INIS)

    Heidari, Shahrokh; Pourarian, Mohammad Rasoul; Naseri, Mosayeb; Gheibi, Reza; Baghfalaki, Masoud; Farouk, Ahmed

    2017-01-01

    Quantum watermarking is a technique to embed specific information, usually the owner’s identification, into quantum cover data such for copyright protection purposes. In this paper, a new scheme for quantum watermarking based on quantum wavelet transforms is proposed which includes scrambling, embedding and extracting procedures. The invisibility and robustness performances of the proposed watermarking method is confirmed by simulation technique. The invisibility of the scheme is examined by the peak-signal-to-noise ratio (PSNR) and the histogram calculation. Furthermore the robustness of the scheme is analyzed by the Bit Error Rate (BER) and the Correlation Two-Dimensional (Corr 2-D) calculation. The simulation results indicate that the proposed watermarking scheme indicate not only acceptable visual quality but also a good resistance against different types of attack. (paper)

  10. Psychoacoustic Music Analysis Based on the Discrete Wavelet Packet Transform

    Directory of Open Access Journals (Sweden)

    Xing He

    2008-01-01

    Full Text Available Psychoacoustical computational models are necessary for the perceptual processing of acoustic signals and have contributed significantly in the development of highly efficient audio analysis and coding. In this paper, we present an approach for the psychoacoustic analysis of musical signals based on the discrete wavelet packet transform. The proposed method mimics the multiresolution properties of the human ear closer than other techniques and it includes simultaneous and temporal auditory masking. Experimental results show that this method provides better masking capabilities and it reduces the signal-to-masking ratio substantially more than other approaches, without introducing audible distortion. This model can lead to greater audio compression by permitting further bit rate reduction and more secure watermarking by providing greater signal space for information hiding.

  11. Scattering transform and LSPTSVM based fault diagnosis of rotating machinery

    Science.gov (United States)

    Ma, Shangjun; Cheng, Bo; Shang, Zhaowei; Liu, Geng

    2018-05-01

    This paper proposes an algorithm for fault diagnosis of rotating machinery to overcome the shortcomings of classical techniques which are noise sensitive in feature extraction and time consuming for training. Based on the scattering transform and the least squares recursive projection twin support vector machine (LSPTSVM), the method has the advantages of high efficiency and insensitivity for noise signal. Using the energy of the scattering coefficients in each sub-band, the features of the vibration signals are obtained. Then, an LSPTSVM classifier is used for fault diagnosis. The new method is compared with other common methods including the proximal support vector machine, the standard support vector machine and multi-scale theory by using fault data for two systems, a motor bearing and a gear box. The results show that the new method proposed in this study is more effective for fault diagnosis of rotating machinery.

  12. Rule-based modularization in model transformation languages illustrated with ATL

    NARCIS (Netherlands)

    Ivanov, Ivan; van den Berg, Klaas; Jouault, Frédéric

    2007-01-01

    This paper studies ways for modularizing transformation definitions in current rule-based model transformation languages. Two scenarios are shown in which the modular units are identified on the basis of relations between source and target metamodels and on the base of generic transformation

  13. 77 FR 38705 - Draft Specification for Airport Light Bases, Transformer Housings, Junction Boxes, and...

    Science.gov (United States)

    2012-06-28

    ... Bases, Transformer Housings, Junction Boxes, and Accessories, Advisory Circular 150/5345- 42G..., Transformer Housings, Junction Boxes, and Accessories Airport Design'' Advisory Circular, AC 150/5345-42G. The Advisory Circular provides standards and recommendations for airport light bases, transformer housings...

  14. Combination of oriented partial differential equation and shearlet transform for denoising in electronic speckle pattern interferometry fringe patterns.

    Science.gov (United States)

    Xu, Wenjun; Tang, Chen; Gu, Fan; Cheng, Jiajia

    2017-04-01

    It is a key step to remove the massive speckle noise in electronic speckle pattern interferometry (ESPI) fringe patterns. In the spatial-domain filtering methods, oriented partial differential equations have been demonstrated to be a powerful tool. In the transform-domain filtering methods, the shearlet transform is a state-of-the-art method. In this paper, we propose a filtering method for ESPI fringe patterns denoising, which is a combination of second-order oriented partial differential equation (SOOPDE) and the shearlet transform, named SOOPDE-Shearlet. Here, the shearlet transform is introduced into the ESPI fringe patterns denoising for the first time. This combination takes advantage of the fact that the spatial-domain filtering method SOOPDE and the transform-domain filtering method shearlet transform benefit from each other. We test the proposed SOOPDE-Shearlet on five experimentally obtained ESPI fringe patterns with poor quality and compare our method with SOOPDE, shearlet transform, windowed Fourier filtering (WFF), and coherence-enhancing diffusion (CEDPDE). Among them, WFF and CEDPDE are the state-of-the-art methods for ESPI fringe patterns denoising in transform domain and spatial domain, respectively. The experimental results have demonstrated the good performance of the proposed SOOPDE-Shearlet.

  15. Wavelet Packet Transform Based Driver Distraction Level Classification Using EEG

    Directory of Open Access Journals (Sweden)

    Mousa Kadhim Wali

    2013-01-01

    Full Text Available We classify the driver distraction level (neutral, low, medium, and high based on different wavelets and classifiers using wireless electroencephalogram (EEG signals. 50 subjects were used for data collection using 14 electrodes. We considered for this research 4 distraction stimuli such as Global Position Systems (GPS, music player, short message service (SMS, and mental tasks. Deriving the amplitude spectrum of three different frequency bands theta, alpha, and beta of EEG signals was based on fusion of discrete wavelet packet transform (DWPT and FFT. Comparing the results of three different classifiers (subtractive fuzzy clustering probabilistic neural network, -nearest neighbor was based on spectral centroid, and power spectral features extracted by different wavelets (db4, db8, sym8, and coif5. The results of this study indicate that the best average accuracy achieved by subtractive fuzzy inference system classifier is 79.21% based on power spectral density feature extracted by sym8 wavelet which gave a good class discrimination under ANOVA test.

  16. In situ observation of electron beam-induced phase transformation of CaCO3 to CaO via ELNES at low electron beam energies.

    Science.gov (United States)

    Golla-Schindler, Ute; Benner, Gerd; Orchowski, Alexander; Kaiser, Ute

    2014-06-01

    It is demonstrated that energy-filtered transmission electron microscope enables following of in situ changes of the Ca-L2,3 edge which can originate from variations in both local symmetry and bond lengths. Low accelerating voltages of 20 and 40 kV slow down radiation damage effects and enable study of the start and finish of phase transformations. We observed electron beam-induced phase transformation of single crystalline calcite (CaCO3) to polycrystalline calcium oxide (CaO) which occurs in different stages. The coordination of Ca in calcite is close to an octahedral one streched along the direction. Changes during phase transformation to an octahedral coordination of Ca in CaO go along with a bond length increase by 5 pm, where oxygen is preserved as a binding partner. Electron loss near-edge structure of the Ca-L2,3 edge show four separated peaks, which all shift toward lower energies during phase transformation at the same time the energy level splitting increases. We suggest that these changes can be mainly addressed to the change of the bond length on the order of picometers. An important pre-condition for such studies is stability of the energy drift in the range of meV over at least 1 h, which is achieved with the sub-Ångström low-voltage transmission electron microscope I prototype microscope.

  17. Modification of dielectric function and electronic structure of the alloys at the phase transformation amorphous-crystalline state

    International Nuclear Information System (INIS)

    Belij, M.U.; Poperenko, L.V.; Shajkevich, I.A.; Karpusha, V.D.; Kravets, V.G.

    1989-01-01

    The relation between the features of the optical spectrum and the electronic structure parameters for non-crystalline nickel- and iron-based alloys is not yet precisely found. Therefore the main purpose of the study consists in investigation of the basic metal band structure modification at metalloid alloying. The density of electron states N(E) and structural parameters of amorphous alloys nickel-M, iron-M, Fe-TM-M (M - metalloid B,Si,C; TM - transition metal 3d (Ti,V,Cr,Mn,Co,Ni), 4d (Nb,Mo), 5d (Hf,Ta,W) and their transformation changes from amorphous (AS) to crystalline state (CS) have been determined. The methods of ellipsometry, Auger-spectroscopy and X-ray absorption spectroscopy are used. The function N(E) of the Ni- and Fe-based alloys has shown 4 density-of-states peaks, one of them located above the Fermi level E F and the others - below it. The observed features of the absorbed spectra of Ni-M (M = B,P) are related both to the interband transition from the levels falling into the occupied peaks of N(E) to the levels at E F , and to the 1-peak-states. When B increases the distance between 1-peak and E F decreases. With introduction of the TM atoms into Fe-B the impurities states related to them are formed above E F . From the X-ray data the cluster with nonhomogeneous electronic density for FeBSi (7.0 nm) and FeNbBSi (7.0 and 4.2 nm along and transverse to foil respectively) are estimated. The frequencies of relaxation and plasma oscillations are also calculated. (author)

  18. Modeling and Analysis of the Common Mode Voltage in a Cascaded H-Bridge Electronic Power Transformer

    Directory of Open Access Journals (Sweden)

    Yun Yang

    2017-09-01

    Full Text Available Electronic power transformers (EPTs have been identified as emerging intelligent electronic devices in the future smart grid, e.g., the Energy Internet, especially in the application of renewable energy conversion and management. Considering that the EPT is directly connected to the medium-voltage grid, e.g., a10 kV distribution system, and its cascaded H-bridges structure, the common mode voltage (CMV issue will be more complex and severe. The CMV will threaten the insulation of the entire EPT device and even produce common mode current. This paper investigates the generated mechanism and characteristics of the CMV in a cascaded H-bridge EPT (CHB-EPT under both balanced and fault grid conditions. First, the CHB-EPT system is introduced. Then, a three-phase simplified circuit model of the high-voltage side of the EPT system is presented. Combined with a unipolar modulation strategy and carrier phase shifting technology by rigorous mathematical analysis and derivation, the EPT internal CMV and its characteristics are obtained. Moreover, the influence of the sinusoidal pulse width modulation dead time is considered and discussed based on analytical calculation. Finally, the simulation results are provided to verify the validity of the aforementioned model and the analysis results. The proposed theoretical analysis method is also suitable for other similar cascaded converters and can provide a useful theoretical guide for structural design and power density optimization.

  19. Zope based electronic operation log system - Zlog

    International Nuclear Information System (INIS)

    Yoshii, K.; Satoh, Y.; Kitabayashi, T.

    2004-01-01

    Since January 2004, the Zope based electronic operation logging system, named Zlog, has been running at the KEKB and AR accelerator facilities. Since Zope is the python based open source web application server software and python language is familiar for the members in the KEKB accelerator control group, we have developed the Zlog system rapidly. In this paper, we report the development history and the present status of Zlog system. Also we show some general plug-in components, called Zope products, have been useful for our Zlog development. (author)

  20. Some aspects of bainite transformation in Fe-based alloys

    International Nuclear Information System (INIS)

    Tsuzaki, K.; Maki, T.

    1995-01-01

    The mechanism of the bainite transformation in carbon containing steels was discussed after presenting our recent experimental results; (1) the bainite transformation has its own C-curve, (2) incomplete phenomenon is a general feature of the bainite transformation, (3) bainitic ferrite grows to a limited size, and (4) bainitic ferrite is highly supersaturated with respect to carbon. It was examined what kinds of interphase boundary structures and carbon concentration gradients in the vicinity of the transformation interface are possible to explain the experimental results. It was concluded that the bainite transformation should be regarded as the transformation that occurs by the movement of a glissile interphase boundary and requires diffusion of interstitial carbon atoms at least to a certain extent in the nucleation and growth stages. (orig.)

  1. Electron Resonance Decay into a Biological Function: Decrease in Viability of E. coli Transformed by Plasmid DNA Irradiated with 0.5-18 eV Electrons.

    Science.gov (United States)

    Kouass Sahbani, S; Cloutier, P; Bass, A D; Hunting, D J; Sanche, L

    2015-10-01

    Transient negative ions (TNIs) are ubiquitous in electron-molecule scattering at low electron impact energies (0-20 eV) and are particularly effective in damaging large biomolecules. Because ionizing radiation generates mostly 0-20 eV electrons, TNIs are expected to play important roles in cell mutagenesis and death during radiotherapeutic cancer treatment, although this hypothesis has never been directly verified. Here, we measure the efficiency of transforming E. coli bacteria by inserting into the cells, pGEM-3ZfL(-) plasmid DNA that confers resistance to the antibiotic ampicillin. Before transformation, plasmids are irradiated with electrons of specific energies between 0.5 and 18 eV. The loss of transformation efficiency plotted as a function of irradiation energy reveals TNIs at 5.5 and 9.5 eV, corresponding to similar states observed in the yields of DNA double strand breaks. We show that TNIs are detectable in the electron-energy dependence of a biological process and can decrease cell viability.

  2. Transformation of carbon tetrachloride in an anaerobic packed-bed reactor without addition of another electron donor

    NARCIS (Netherlands)

    de Best, JH; Hunneman, P; Doddema, HJ; Janssen, DB; Harder, W; Doddema, Hans J.

    1999-01-01

    Carbon tetrachloride (52 mu M) was biodegraded for more than 72% in an anaerobic packed-bed reactor without addition of an external electron donor. The chloride mass balance demonstrated that all carbon tetrachloride transformed was completely dechlorinated. Chloroform and dichloromethane were

  3. Super electron donor-mediated reductive transformation of nitrobenzenes: a novel strategy to synthesize azobenzenes and phenazines.

    Science.gov (United States)

    Nozawa-Kumada, Kanako; Abe, Erina; Ito, Shungo; Shigeno, Masanori; Kondo, Yoshinori

    2018-05-02

    The transformation of nitrobenzenes into azobenzenes by pyridine-derived super electron donor 2 is described. This method provides an efficient synthesis of azobenzenes because of not requiring the use of expensive transition-metals, toxic or flammable reagents, or harsh conditions. Moreover, when using 2-fluoronitrobenzenes as substrates, phenazines were found to be obtained. The process affords a novel synthesis of phenazines.

  4. Transformation of carbon tetrachloride in an anaerobic packed-bed reactor without addition of another electron donor

    NARCIS (Netherlands)

    Best, J.H. de; Hunneman, P.; Doddema, H.J.; Janssen, D.B.; Harder, W.

    1999-01-01

    Carbon tetrachloride (52 μM) was biodegraded for more than 72% in an anaerobic packed-bed reactor without addition of an external electron donor. The chloride mass balance demonstrated that all carbon tetrachloride transformed was completely dechlorinated. Chloroform and dichloromethane were

  5. Studies of the structure of insulin fibrils by Fourier transform infrared (FTIR) spectroscopy and electron microscopy.

    Science.gov (United States)

    Nielsen, L; Frokjaer, S; Carpenter, J F; Brange, J

    2001-01-01

    Fibril formation (aggregation) of insulin was investigated in acid media by visual inspection, transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy. Insulin fibrillated faster in hydrochloric acid than in acetic acid at elevated temperatures, whereas the fibrillation tendencies were reversed at ambient temperatures. Electron micrographs showed that bovine insulin fibrils consisted of long fibers with a diameter of 5 to 10 nm and lengths of several microns. The fibrils appeared either as helical filaments (in hydrochloric acid) or arranged laterally in bundles (in acetic acid, NaCl). Freeze-thawing cycles broke the fibrils into shorter segments. FTIR spectroscopy showed that the native secondary structure of insulin was identical in hydrochloric acid and acetic acid, whereas the secondary structure of fibrils formed in hydrochloric acid was different from that formed in acetic acid. Fibrils of bovine insulin prepared by heating or agitating an acid solution of insulin showed an increased content of beta-sheet (mostly intermolecular) and a decrease in the intensity of the alpha-helix band. In hydrochloric acid, the frequencies of the beta-sheet bands depended on whether the fibrillation was induced by heating or agitation. This difference was not seen in acetic acid. Freeze-thawing cycles of the fibrils in hydrochloric acid caused an increase in the intensity of the band at 1635 cm(-1) concomitant with reduction of the band at 1622 cm(-1). The results showed that the structure of insulin fibrils is highly dependent on the composition of the acid media and on the treatment. Copyright 2001 Wiley-Liss Inc. and the American Pharmaceutical Association J Pharm Sci 90: 29-37, 2001

  6. Comparison on Integer Wavelet Transforms in Spherical Wavelet Based Image Based Relighting

    Institute of Scientific and Technical Information of China (English)

    WANGZe; LEEYin; LEUNGChising; WONGTientsin; ZHUYisheng

    2003-01-01

    To provide a good quality rendering in the Image based relighting (IBL) system, tremendous reference images under various illumination conditions are needed. Therefore data compression is essential to enable interactive action. And the rendering speed is another crucial consideration for real applications. Based on Spherical wavelet transform (SWT), this paper presents a quick representation method with Integer wavelet transform (IWT) for the IBL system. It focuses on comparison on different IWTs with the Embedded zerotree wavelet (EZW) used in the IBL system. The whole compression procedure contains two major compression steps. Firstly, SWT is applied to consider the correlation among different reference images. Secondly, the SW transformed images are compressed with IWT based image compression approach. Two IWTs are used and good results are showed in the simulations.

  7. Phase transformations and thermodynamics of aluminum-based metallic glasses

    Science.gov (United States)

    Gao, Changhua (Michael)

    This thesis examines the thermodynamics and associated kinetics and phase transformations of the glass forming Al-Ni-Gd and Al-Fe-Gd systems. In order to fully understand the unique glass forming ability (GFA) of Al-based metallic glasses, the ternary Al-Fe-Gd and Al-Ni-Gd systems in their Al-rich corners were examined experimentally to assist in a thermodynamic assessment. The solid-state phase equilibria are determined using XRD and TEM-EDS techniques. While this work basically confirms the solid-state equilibria in Al-Fe-Gd reported previously, the ternary phase in Al-Ni-Gd system has been identified to be Al15Ni3Gd2 rather than Al16Ni 3Gd reported in the literature. DTA analysis of 24 alloys in the Al-Fe-Gd system and 42 alloys in the Al-Ni-Gd system have yielded critical temperatures pertaining to the solid-liquid transition. Based on these data and information from the literature, a self-consistent thermodynamic database for these systems has been developed using the CALPHAD technique. Parameters describing the Gibbs free energy for various phases of the Al-Gd, Al-Fe-Gd and Al-Ni-Gd systems are manually optimized in this study. Once constructed, the database is used to calculate driving forces for nucleation of crystalline phases which can qualitatively explain the phase formation sequence during crystallization at low temperatures. It was also confirmed that alloy compositions with the lowest Gibbs free energy difference between the equilibrium state and undercooled liquid state exhibit better GFA than other chemistries. Based on 250°C isothermal devitrification phase transformations of 17 Al-Ni-Gd alloys, a phase formation sequence map is constructed. Fcc-Al nanocrystals are formed first in most of the alloys studied, but eutectic crystallization of a metastable phase and fcc-Al is also observed. Addition of Al or Ni promotes fcc-Al phase formation, while increasing Gd suppresses it. The continuous heating DSC scans revealed that crystallization in Al

  8. Computational Intelligence and Wavelet Transform Based Metamodel for Efficient Generation of Not-Yet Simulated Waveforms.

    Directory of Open Access Journals (Sweden)

    Gabriel Oltean

    Full Text Available The design and verification of complex electronic systems, especially the analog and mixed-signal ones, prove to be extremely time consuming tasks, if only circuit-level simulations are involved. A significant amount of time can be saved if a cost effective solution is used for the extensive analysis of the system, under all conceivable conditions. This paper proposes a data-driven method to build fast to evaluate, but also accurate metamodels capable of generating not-yet simulated waveforms as a function of different combinations of the parameters of the system. The necessary data are obtained by early-stage simulation of an electronic control system from the automotive industry. The metamodel development is based on three key elements: a wavelet transform for waveform characterization, a genetic algorithm optimization to detect the optimal wavelet transform and to identify the most relevant decomposition coefficients, and an artificial neuronal network to derive the relevant coefficients of the wavelet transform for any new parameters combination. The resulted metamodels for three different waveform families are fully reliable. They satisfy the required key points: high accuracy (a maximum mean squared error of 7.1x10-5 for the unity-based normalized waveforms, efficiency (fully affordable computational effort for metamodel build-up: maximum 18 minutes on a general purpose computer, and simplicity (less than 1 second for running the metamodel, the user only provides the parameters combination. The metamodels can be used for very efficient generation of new waveforms, for any possible combination of dependent parameters, offering the possibility to explore the entire design space. A wide range of possibilities becomes achievable for the user, such as: all design corners can be analyzed, possible worst-case situations can be investigated, extreme values of waveforms can be discovered, sensitivity analyses can be performed (the influence of each

  9. Computational Intelligence and Wavelet Transform Based Metamodel for Efficient Generation of Not-Yet Simulated Waveforms.

    Science.gov (United States)

    Oltean, Gabriel; Ivanciu, Laura-Nicoleta

    2016-01-01

    The design and verification of complex electronic systems, especially the analog and mixed-signal ones, prove to be extremely time consuming tasks, if only circuit-level simulations are involved. A significant amount of time can be saved if a cost effective solution is used for the extensive analysis of the system, under all conceivable conditions. This paper proposes a data-driven method to build fast to evaluate, but also accurate metamodels capable of generating not-yet simulated waveforms as a function of different combinations of the parameters of the system. The necessary data are obtained by early-stage simulation of an electronic control system from the automotive industry. The metamodel development is based on three key elements: a wavelet transform for waveform characterization, a genetic algorithm optimization to detect the optimal wavelet transform and to identify the most relevant decomposition coefficients, and an artificial neuronal network to derive the relevant coefficients of the wavelet transform for any new parameters combination. The resulted metamodels for three different waveform families are fully reliable. They satisfy the required key points: high accuracy (a maximum mean squared error of 7.1x10-5 for the unity-based normalized waveforms), efficiency (fully affordable computational effort for metamodel build-up: maximum 18 minutes on a general purpose computer), and simplicity (less than 1 second for running the metamodel, the user only provides the parameters combination). The metamodels can be used for very efficient generation of new waveforms, for any possible combination of dependent parameters, offering the possibility to explore the entire design space. A wide range of possibilities becomes achievable for the user, such as: all design corners can be analyzed, possible worst-case situations can be investigated, extreme values of waveforms can be discovered, sensitivity analyses can be performed (the influence of each parameter on the

  10. Computational Intelligence and Wavelet Transform Based Metamodel for Efficient Generation of Not-Yet Simulated Waveforms

    Science.gov (United States)

    Oltean, Gabriel; Ivanciu, Laura-Nicoleta

    2016-01-01

    The design and verification of complex electronic systems, especially the analog and mixed-signal ones, prove to be extremely time consuming tasks, if only circuit-level simulations are involved. A significant amount of time can be saved if a cost effective solution is used for the extensive analysis of the system, under all conceivable conditions. This paper proposes a data-driven method to build fast to evaluate, but also accurate metamodels capable of generating not-yet simulated waveforms as a function of different combinations of the parameters of the system. The necessary data are obtained by early-stage simulation of an electronic control system from the automotive industry. The metamodel development is based on three key elements: a wavelet transform for waveform characterization, a genetic algorithm optimization to detect the optimal wavelet transform and to identify the most relevant decomposition coefficients, and an artificial neuronal network to derive the relevant coefficients of the wavelet transform for any new parameters combination. The resulted metamodels for three different waveform families are fully reliable. They satisfy the required key points: high accuracy (a maximum mean squared error of 7.1x10-5 for the unity-based normalized waveforms), efficiency (fully affordable computational effort for metamodel build-up: maximum 18 minutes on a general purpose computer), and simplicity (less than 1 second for running the metamodel, the user only provides the parameters combination). The metamodels can be used for very efficient generation of new waveforms, for any possible combination of dependent parameters, offering the possibility to explore the entire design space. A wide range of possibilities becomes achievable for the user, such as: all design corners can be analyzed, possible worst-case situations can be investigated, extreme values of waveforms can be discovered, sensitivity analyses can be performed (the influence of each parameter on the

  11. Cross sections for electron-impact excitation of argon by fourier transform spectroscopy

    International Nuclear Information System (INIS)

    Chilton, J.E.; Boffard, J.B.; Chun C.L.

    1996-01-01

    The authors report absolute measurements of electron-impact excitation cross sections out of the ground level to the ten levels in the 3p 5 4p configuration of argon. The apparent excitation cross sections are determined by measuring the optical cross sections for the emission lines in the 3p 5 4p → 3p 5 4s manifold. For cascade corrections the authors measured the optical cross sections for the various 3p 5 5s → 3p 5 4p and 3p 5 4p infrared lines using a Fourier transform weak emission spectrometer to obtain the direct excitation cross sections from the optical data. Although the optical cross sections vary with pressure in the regime of 0.1 to 6 mTorr, the direct cross sections remain invariant. These pressure effects are understood within the framework of a radiation-reabsorption model. The excitation functions for the different transitions are also found to show considerable variation in shape

  12. Integrated reconfigurable photonic filters based on interferometric fractional Hilbert transforms.

    Science.gov (United States)

    Sima, C; Cai, B; Liu, B; Gao, Y; Yu, Y; Gates, J C; Zervas, M N; Smith, P G R; Liu, D

    2017-10-01

    In this paper, we present integrated reconfigurable photonic filters using fractional Hilbert transformers (FrHTs) and optical phase tuning structure within the silica-on-silicon platform. The proposed structure, including grating-based FrHTs, an X-coupler, and a pair of thermal tuning filaments, is fabricated through the direct UV grating writing technique. The thermal tuning effect is realized by the controllable microheaters located on the two arms of the X-coupler. We investigate the 200 GHz maximum bandwidth photonic FrHTs based on apodized planar Bragg gratings, and analyze the reflection spectrum responses. Through device integration and thermal modulation, the device could operate as photonic notch filters with 5 GHz linewidth and controllable single sideband suppression filters with measured 12 dB suppression ratio. A 50 GHz instantaneous frequency measuring system using this device is also schematically proposed and analyzed with potential 3 dB measurement improvement. The device could be configured with these multiple functions according to need. The reconfigurable structure has great potential in ultrafast all-optical signal processing fields.

  13. Anomalous acoustic effect during martensitic transformations in titanium nickelide base alloys

    International Nuclear Information System (INIS)

    Plotnikov, V.A.; Kokhanenko, D.V.

    2002-01-01

    One carried out experiments to determine effect of external static stress on martensitic transformations and acoustic emission, Martensitic transformations in titanium nickelide base alloys under mechanical stress were determined to change nature of acoustic emission to anomalous one - cycling of transformations under gradual increase of mechanical stress during direct martensitic transformation was followed by increase of acoustic emission energy instead of reduction. The mentioned nature of acoustic emission is indicative of essential effect of external stress on martensitic transformations and energy dissipation during transformations [ru

  14. Dielectric properties of transformer paper impregnated by mineral oil based magnetic fluid

    International Nuclear Information System (INIS)

    Timko, M; Marton, K; Tomco, L; Kopcansky, P; Koneracka, M

    2010-01-01

    The influence of combined magnetic and electric field on permittivity of transformer paper used in power transformers was observed. Transformer paper was impregnated by pure transformer oil ITO 100 and magnetic fluids based on transformer oil ITO 100 with different concentrations of magnetite nanoparticles. The measurements were carried out with help of high precision capacitance bridge. The electric intensity between circular planar electrodes was in the region of weak electric field (E > 10 6 V/m). The increase of electric permittivity of transformer paper impregnated by magnetic fluid opposite pure transformer paper was observed. The experiments showed that permittivity of insulator system consisting of pure transformer paper and impregnated transformer paper naturally depends on number of paper layers. The magnetodielectric effect was found to be dependent on magnetite nanoparticles concentration in magnetic fluids.

  15. An 8-GW long-pulse generator based on Tesla transformer and pulse forming network.

    Science.gov (United States)

    Su, Jiancang; Zhang, Xibo; Li, Rui; Zhao, Liang; Sun, Xu; Wang, Limin; Zeng, Bo; Cheng, Jie; Wang, Ying; Peng, Jianchang; Song, Xiaoxin

    2014-06-01

    A long-pulse generator TPG700L based on a Tesla transformer and a series pulse forming network (PFN) is constructed to generate intense electron beams for the purpose of high power microwave (HPM) generation. The TPG700L mainly consists of a 12-stage PFN, a built-in Tesla transformer in a pulse forming line, a three-electrode gas switch, a transmission line with a trigger, and a load. The Tesla transformer and the compact PFN are the key technologies for the development of the TPG700L. This generator can output electrical pulses with a width as long as 200 ns at a level of 8 GW and a repetition rate of 50 Hz. When used to drive a relative backward wave oscillator for HPM generation, the electrical pulse width is about 100 ns on a voltage level of 520 kV. Factors affecting the pulse waveform of the TPG700L are also discussed. At present, the TPG700L performs well for long-pulse HPM generation in our laboratory.

  16. An 8-GW long-pulse generator based on Tesla transformer and pulse forming network

    Energy Technology Data Exchange (ETDEWEB)

    Su, Jiancang; Zhang, Xibo; Li, Rui; Zhao, Liang, E-mail: zhaoliang0526@163.com; Sun, Xu; Wang, Limin; Zeng, Bo; Cheng, Jie; Wang, Ying; Peng, Jianchang; Song, Xiaoxin [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi' an, Shaanxi 710024 (China)

    2014-06-15

    A long-pulse generator TPG700L based on a Tesla transformer and a series pulse forming network (PFN) is constructed to generate intense electron beams for the purpose of high power microwave (HPM) generation. The TPG700L mainly consists of a 12-stage PFN, a built-in Tesla transformer in a pulse forming line, a three-electrode gas switch, a transmission line with a trigger, and a load. The Tesla transformer and the compact PFN are the key technologies for the development of the TPG700L. This generator can output electrical pulses with a width as long as 200 ns at a level of 8 GW and a repetition rate of 50 Hz. When used to drive a relative backward wave oscillator for HPM generation, the electrical pulse width is about 100 ns on a voltage level of 520 kV. Factors affecting the pulse waveform of the TPG700L are also discussed. At present, the TPG700L performs well for long-pulse HPM generation in our laboratory.

  17. Discrimination Between Inrush and Short Circuit Currents in Differential Protection of Power Transformer Based on Correlation Method Using the Wavelet Transform

    OpenAIRE

    M. Rasoulpoor; M. Banejad; A. Ahmadyfard

    2011-01-01

    This paper presents a novel technique for transformer differential protection to prevent incorrect operation due to inrush current. The proposed method in this paper is based on time-frequency transform known as the Wavelet transform. The discrete Wavelet transform is used for analysis the differential current signals in time and frequency domains. The investigation on the energy distribution of the signal on the discrete Wavelet transform components shows the difference distribution between ...

  18. Charge transport through DNA based electronic barriers

    Science.gov (United States)

    Patil, Sunil R.; Chawda, Vivek; Qi, Jianqing; Anantram, M. P.; Sinha, Niraj

    2018-05-01

    We report charge transport in electronic 'barriers' constructed by sequence engineering in DNA. Considering the ionization potentials of Thymine-Adenine (AT) and Guanine-Cytosine (GC) base pairs, we treat AT as 'barriers'. The effect of DNA conformation (A and B form) on charge transport is also investigated. Particularly, the effect of width of 'barriers' on hole transport is investigated. Density functional theory (DFT) calculations are performed on energy minimized DNA structures to obtain the electronic Hamiltonian. The quantum transport calculations are performed using the Landauer-Buttiker framework. Our main findings are contrary to previous studies. We find that a longer A-DNA with more AT base pairs can conduct better than shorter A-DNA with a smaller number of AT base pairs. We also find that some sequences of A-DNA can conduct better than a corresponding B-DNA with the same sequence. The counterions mediated charge transport and long range interactions are speculated to be responsible for counter-intuitive length and AT content dependence of conductance of A-DNA.

  19. Electron Beam Diagnostics in Plasmas Based on Electron Beam Ionization

    Science.gov (United States)

    Leonhardt, Darrin; Leal-Quiros, Edbertho; Blackwell, David; Walton, Scott; Murphy, Donald; Fernsler, Richard; Meger, Robert

    2001-10-01

    Over the last few years, electron beam ionization has been shown to be a viable generator of high density plasmas with numerous applications in materials modification. To better understand these plasmas, we have fielded electron beam diagnostics to more clearly understand the propagation of the beam as it travels through the background gas and creates the plasma. These diagnostics vary greatly in sophistication, ranging from differentially pumped systems with energy selective elements to metal 'hockey pucks' covered with thin layers of insulation to electrically isolate the detector from the plasma but pass high energy beam electrons. Most importantly, absolute measurements of spatially resolved beam current densities are measured in a variety of pulsed and continuous beam sources. The energy distribution of the beam current(s) will be further discussed, through experiments incorporating various energy resolving elements such as simple grids and more sophisticated cylindrical lens geometries. The results are compared with other experiments of high energy electron beams through gases and appropriate disparities and caveats will be discussed. Finally, plasma parameters are correlated to the measured beam parameters for a more global picture of electron beam produced plasmas.

  20. Comparison study on transformation of iron oxyhydroxides: Based on theoretical and experimental data

    International Nuclear Information System (INIS)

    Lu Bin; Guo Hui; Li Ping; Liu Hui; Wei Yu; Hou Denglu

    2011-01-01

    We have investigated the catalytic transformation of ferrihydrite, feroxyhyte, and lepidocrocite in the presence of Fe(II). In this paper, the transformation from akaganeite and goethite to hematite in the presence of trace Fe(II) was studied in detail. The result indicates that trace Fe(II) can accelerate the transformation of akaganeite and goethite. Compared with the transformation of other iron oxyhydroxides (e.g., ferrihydrite, feroxyhyte, lepidocrocite, and akaganeite), a complete transformation from goethite to hematite was not observed in the presence of Fe(II). On the basis of our earlier and present experimental results, the transformation of various iron oxyhydroxides was compared based on their thermodynamic stability, crystalline structure, transformation mechanism, and transformation time. - Graphical abstract: The transformation of various iron oxyhydroxides in the presence of trace Fe(II) was compared based on experimental results, thermodynamic stability, crystalline structure, and transformation mechanism. Highlights: → Fe(II) can accelerate the transformation from akaganeite to hematite. → Small particles of goethite can transform to hematite in the presence of Fe(II). → Some hematite particles were found to be embedded within the crystal of goethite. → The relationship between structure and transformation mechanism was revealed.

  1. Rolling Bearing Fault Diagnosis Based on an Improved HTT Transform.

    Science.gov (United States)

    Pang, Bin; Tang, Guiji; Tian, Tian; Zhou, Chong

    2018-04-14

    When rolling bearing failure occurs, vibration signals generally contain different signal components, such as impulsive fault feature signals, background noise and harmonic interference signals. One of the most challenging aspects of rolling bearing fault diagnosis is how to inhibit noise and harmonic interference signals, while enhancing impulsive fault feature signals. This paper presents a novel bearing fault diagnosis method, namely an improved Hilbert time-time (IHTT) transform, by combining a Hilbert time-time (HTT) transform with principal component analysis (PCA). Firstly, the HTT transform was performed on vibration signals to derive a HTT transform matrix. Then, PCA was employed to de-noise the HTT transform matrix in order to improve the robustness of the HTT transform. Finally, the diagonal time series of the de-noised HTT transform matrix was extracted as the enhanced impulsive fault feature signal and the contained fault characteristic information was identified through further analyses of amplitude and envelope spectrums. Both simulated and experimental analyses validated the superiority of the presented method for detecting bearing failures.

  2. Linear Transformer Drivers for Z-pinch Based Propulsion

    Science.gov (United States)

    Adams, Robert; Seidler, William; Giddens, Patrick; Fabisinski, Leo; Cassibry, Jason

    2017-01-01

    The MSFC/UAH team has been developing of a novel power management and distribution system called a Linear Transformer Driver (LTD). LTD's hold the promise of dramatically reducing the required mass to drive a z-pinch by replacing the capacitor banks which constitute half the mass of the entire system. The MSFC?UAH tea, is developing this technology in hope of integrating it with the Pulsed Fission Fusion (PuFF) propulsion concept. High-Voltage pulsed power systems used for Z-Pinch experimentation have in the past largely been based on Marx Generators. Marx generators deliver the voltage and current required for the Z-Pinch, but suffer from two significant drawbacks when applied to a flight system: they are very massive, consisting of high-voltage capacitor banks insulated in oil-filled tanks and they do not lend themselves to rapid pulsing. The overall goal of Phase 2 is to demonstrate the construction of a higher voltage stack from a number of cavities each of the design proven in Phase 1 and to characterize and understand the techniques for designing the stack. The overall goal of Phase 3 is to demonstrate the feasibility of constructing a higher energy cavity from a number of smaller LTD stacks, to characterize and understand the way in which the constituent stacks combine, and to extend this demonstration LTD to serve as the basis for a 64 kJ pulse generator for Z-Pinch experiments.

  3. Model based design of electronic throttle control

    Science.gov (United States)

    Cherian, Fenin; Ranjan, Ashish; Bhowmick, Pathikrit; Rammohan, A.

    2017-11-01

    With the advent of torque based Engine Management Systems, the precise control and robust performance of the throttle body becomes a key factor in the overall performance of the vehicle. Electronic Throttle Control provides benefits such as improved air-fuel ratio for improving the vehicle performance and lower exhausts emissions to meet the stringent emission norms. Modern vehicles facilitate various features such as Cruise Control, Traction Control, Electronic Stability Program and Pre-crash systems. These systems require control over engine power without driver intervention, which is not possible with conventional mechanical throttle system. Thus these systems are integrated to function with the electronic throttle control. However, due to inherent non-linearities in the throttle body, the control becomes a difficult task. In order to eliminate the influence of this hysteresis at the initial operation of the butterfly valve, a control to compensate the shortage must be added to the duty required for starting throttle operation when the initial operation is detected. Therefore, a lot of work is being done in this field to incorporate the various nonlinearities to achieve robust control. In our present work, the ETB was tested to verify the working of the system. Calibration of the TPS sensors was carried out in order to acquire accurate throttle opening angle. The response of the calibrated system was then plotted against a step input signal. A linear model of the ETB was prepared using Simulink and its response was compared with the experimental data to find out the initial deviation of the model from the actual system. To reduce this deviation, non-linearities from existing literature were introduced to the system and a response analysis was performed to check the deviation from the actual system. Based on this investigation, an introduction of a new nonlinearity parameter can be used in future to reduce the deviation further making the control of the ETB more

  4. Multiparametric electronic devices based on nuclear tracks

    Energy Technology Data Exchange (ETDEWEB)

    Fink, D. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany)], E-mail: FINK@HMI.DE; Saad, A. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany); Basic Science Department, Faculty of Science, Al Balqa University, Salt (Jordan); Dhamodaran, S. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany); School of Physics, University of Hyderabad, Hyderabad 500 046 (India); Chandra, A. [HMI Berlin, Glienicker Str. 100, 14109 Berlin (Germany); Department of Physics and Astrophysics, University of Delhi, Delhi 110 007 (India); Fahrner, W.R. [Chair of Electronic Devices, Institute of Electrotechnique, Fernuniversitaet, Hagen (Germany); Hoppe, K. [South Westfalia University of Applied Sciences, Hagen (Germany); Chadderton, L.T. [Institute of Advanced Studies, ANU Canberra, GPO Box 4, ACT (Australia)

    2008-08-15

    An overview is given on a family of novel electronic devices consisting of an insulating layer containing conducting or semiconducting nuclear tracks, deposited on a semiconducting substrate, and connected by at least one back and two surface contacts. Conducting and semiconducting latent tracks may emerge directly from swift heavy ion irradiation. Etched tracks in insulators can be filled with adequate materials to make them conducting or semiconducting. For this purpose metallic or semiconducting nanoclusters were deposited. We have denoted termed these devices made with latent tracks as 'tunable electronic anisotropic material on semiconductor' (TEAMS), if based on latent ion tracks, and as 'tunable electronic material in pores in oxide on semiconductor' (TEMPOS), if based on etched tracks. Depending on the band-to-band transition between tracks and substrate and on the ratio of surface to track conductivity, the current/voltage characteristics of TEAMS and TEMPOS structures can be modified in many different ways leading to tunable resistors, capacitors and diodes. Both devices show negative differential resistances. This should enable tunable tunneldiodes. TEAMS or TEMPOS structures can be controlled by various external physical and/or chemical parameters leading to sensors. It is even possible to combine different input currents and/or external parameters according to AND/OR logics. The currents through a clustered layer on a TEMPOS structure can be described by the Barbasi-Albert model of network theory enabling to calculate a 'radius of influence'r{sub ROI} around each surface contact, beyond which neighboring contacts do not influence each other. The radius of influence can be well below 1{mu}m leading to nanometric TEMPOS structures.

  5. Multiparametric electronic devices based on nuclear tracks

    International Nuclear Information System (INIS)

    Fink, D.; Saad, A.; Dhamodaran, S.; Chandra, A.; Fahrner, W.R.; Hoppe, K.; Chadderton, L.T.

    2008-01-01

    An overview is given on a family of novel electronic devices consisting of an insulating layer containing conducting or semiconducting nuclear tracks, deposited on a semiconducting substrate, and connected by at least one back and two surface contacts. Conducting and semiconducting latent tracks may emerge directly from swift heavy ion irradiation. Etched tracks in insulators can be filled with adequate materials to make them conducting or semiconducting. For this purpose metallic or semiconducting nanoclusters were deposited. We have denoted termed these devices made with latent tracks as 'tunable electronic anisotropic material on semiconductor' (TEAMS), if based on latent ion tracks, and as 'tunable electronic material in pores in oxide on semiconductor' (TEMPOS), if based on etched tracks. Depending on the band-to-band transition between tracks and substrate and on the ratio of surface to track conductivity, the current/voltage characteristics of TEAMS and TEMPOS structures can be modified in many different ways leading to tunable resistors, capacitors and diodes. Both devices show negative differential resistances. This should enable tunable tunneldiodes. TEAMS or TEMPOS structures can be controlled by various external physical and/or chemical parameters leading to sensors. It is even possible to combine different input currents and/or external parameters according to AND/OR logics. The currents through a clustered layer on a TEMPOS structure can be described by the Barbasi-Albert model of network theory enabling to calculate a 'radius of influence'r ROI around each surface contact, beyond which neighboring contacts do not influence each other. The radius of influence can be well below 1μm leading to nanometric TEMPOS structures

  6. Spin orbit torque based electronic neuron

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, Abhronil, E-mail: asengup@purdue.edu; Choday, Sri Harsha; Kim, Yusung; Roy, Kaushik [School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)

    2015-04-06

    A device based on current-induced spin-orbit torque (SOT) that functions as an electronic neuron is proposed in this work. The SOT device implements an artificial neuron's thresholding (transfer) function. In the first step of a two-step switching scheme, a charge current places the magnetization of a nano-magnet along the hard-axis, i.e., an unstable point for the magnet. In the second step, the SOT device (neuron) receives a current (from the synapses) which moves the magnetization from the unstable point to one of the two stable states. The polarity of the synaptic current encodes the excitatory and inhibitory nature of the neuron input and determines the final orientation of the magnetization. A resistive crossbar array, functioning as synapses, generates a bipolar current that is a weighted sum of the inputs. The simulation of a two layer feed-forward artificial neural network based on the SOT electronic neuron shows that it consumes ∼3× lower power than a 45 nm digital CMOS implementation, while reaching ∼80% accuracy in the classification of 100 images of handwritten digits from the MNIST dataset.

  7. Spin orbit torque based electronic neuron

    International Nuclear Information System (INIS)

    Sengupta, Abhronil; Choday, Sri Harsha; Kim, Yusung; Roy, Kaushik

    2015-01-01

    A device based on current-induced spin-orbit torque (SOT) that functions as an electronic neuron is proposed in this work. The SOT device implements an artificial neuron's thresholding (transfer) function. In the first step of a two-step switching scheme, a charge current places the magnetization of a nano-magnet along the hard-axis, i.e., an unstable point for the magnet. In the second step, the SOT device (neuron) receives a current (from the synapses) which moves the magnetization from the unstable point to one of the two stable states. The polarity of the synaptic current encodes the excitatory and inhibitory nature of the neuron input and determines the final orientation of the magnetization. A resistive crossbar array, functioning as synapses, generates a bipolar current that is a weighted sum of the inputs. The simulation of a two layer feed-forward artificial neural network based on the SOT electronic neuron shows that it consumes ∼3× lower power than a 45 nm digital CMOS implementation, while reaching ∼80% accuracy in the classification of 100 images of handwritten digits from the MNIST dataset

  8. Study of planar defects associated to martensite transformation in copper alloys by transmission electron microscopy

    International Nuclear Information System (INIS)

    Condo, A.M.

    1997-01-01

    In this work the planar faults in non-compact planes (non-basal faults) in the 2H and 18R martensitic phases in Cu-Zn-Al alloys are analyzed. The study was carried out using transmission electron microscopy (TEM) combining the two-beam condition technique, high resolution transmission electron microscopy (HRTEM) and computer simulated images. The displacement vectors of the faults were determined. It was found that these vectors were different from those of the basal faults, even though the faults are connected. One single class of non-basal faults, named F 1 , was observed in the 2H phase, whereas two different classes were found in the 18R phase, named F o and F x . In the latter phase non-basal faults made up of different segments of F o and F x faults were observed (composed faults). The Burgers vectors of the partial dislocations at the edges of the non-basal faults were determined in both phases. Additionally, the Burgers vectors of the intermediate dislocations found between the different segments of the composed faults in the 18R phase were determined. It was verified that there exist two types of dislocations with Burgers vectors that differ in approximately 1/3 [100]. It was found that the presence of a particular dislocation type depends on the arrangement between the non-basal fault and the basal fault that originates the dislocation. The internal structure of the non-basal faults in the 18R phase was studied with HRTEM. It was observed that the shift of the crystal planes due to the presence of the faults occurs in a region of a finite extension of about 1.5 nm. It was also observed that in this region the crystal planes appear rotated and lose the characteristic corrugation they have in the 18R structure. As a consequence of this, new translation vectors appear in the defect; this fact could be reflected in new plastic deformation systems. The rotation of the crystal planes in the non-basal faulted area of the 18R phase was compared with the rotation

  9. The Transformational Quality of Base Realignment and Closure 2005

    National Research Council Canada - National Science Library

    Lathroum, John A

    2006-01-01

    ...) our infrastructure with defense strategy.. .by maximiz(ing) warfighting capability and efficiency." This study examines the transformational capability of BRAC 2005 by analyzing three recommendations (USA: Operational Army (IGPBS), E&T...

  10. Design and performance of a pulse transformer based on Fe-based nanocrystalline core.

    Science.gov (United States)

    Yi, Liu; Xibo, Feng; Lin, Fuchang

    2011-08-01

    A dry-type pulse transformer based on Fe-based nanocrystalline core with a load of 0.88 nF, output voltage of more than 65 kV, and winding ratio of 46 is designed and constructed. The dynamic characteristics of Fe-based nanocrystalline core under the impulse with the pulse width of several microseconds were studied. The pulse width and incremental flux density have an important effect on the pulse permeability, so the pulse permeability is measured under a certain pulse width and incremental flux density. The minimal volume of the toroidal pulse transformer core is determined by the coupling coefficient, the capacitors of the resonant charging circuit, incremental flux density, and pulse permeability. The factors of the charging time, ratio, and energy transmission efficiency in the resonant charging circuit based on magnetic core-type pulse transformer are analyzed. Experimental results of the pulse transformer are in good agreement with the theoretical calculation. When the primary capacitor is 3.17 μF and charge voltage is 1.8 kV, a voltage across the secondary capacitor of 0.88 nF with peak value of 68.5 kV, rise time (10%-90%) of 1.80 μs is obtained.

  11. Nonlinear Effects in Piezoelectric Transformers Explained by Thermal-Electric Model Based on a Hypothesis of Self-Heating

    DEFF Research Database (Denmark)

    Andersen, Thomas; Andersen, Michael A. E.; Thomsen, Ole Cornelius

    2012-01-01

    As the trend within power electronic still goes in the direction of higher power density and higher efficiency, it is necessary to develop new topologies and push the limit for the existing technology. Piezoelectric transformers are a fast developing technology to improve efficiency and increase ...... is developed to explain nonlinearities as voltage jumps and voltage saturation and thereby avoid the complex theory of electro elasticity. The model is based on the hypothesis of self-heating and tested with measurements with good correlation....

  12. State-of-the-art piezoelectric transformer-based switch mode power supplies

    DEFF Research Database (Denmark)

    Ekhtiari, Marzieh; Zhang, Zhe; Andersen, Michael A. E.

    2014-01-01

    Inductorless switch mode power supplies based on piezoelectric transformers are used to replace conventional transformers in high power density switch mode power supplies. Even though piezoelectric-based converters exhibit a high d egree of nonlinearity, it is desirable to use piezoelectric transfo...... discusses power supplies with the trend evaluation of piezoelectric transformer-based converter topologies and control methods. The challenges of piezoelectric transformers regarding soft switching capability and nonlinearity are addressed. This paper can be used as a guideline f or choosing a proper...... topology of piezoelectric-based switch mode power supply and a control method for the required application....

  13. Solution of the weighted symmetric similarity transformations based on quaternions

    Science.gov (United States)

    Mercan, H.; Akyilmaz, O.; Aydin, C.

    2017-12-01

    A new method through Gauss-Helmert model of adjustment is presented for the solution of the similarity transformations, either 3D or 2D, in the frame of errors-in-variables (EIV) model. EIV model assumes that all the variables in the mathematical model are contaminated by random errors. Total least squares estimation technique may be used to solve the EIV model. Accounting for the heteroscedastic uncertainty both in the target and the source coordinates, that is the more common and general case in practice, leads to a more realistic estimation of the transformation parameters. The presented algorithm can handle the heteroscedastic transformation problems, i.e., positions of the both target and the source points may have full covariance matrices. Therefore, there is no limitation such as the isotropic or the homogenous accuracy for the reference point coordinates. The developed algorithm takes the advantage of the quaternion definition which uniquely represents a 3D rotation matrix. The transformation parameters: scale, translations, and the quaternion (so that the rotation matrix) along with their covariances, are iteratively estimated with rapid convergence. Moreover, prior least squares (LS) estimation of the unknown transformation parameters is not required to start the iterations. We also show that the developed method can also be used to estimate the 2D similarity transformation parameters by simply treating the problem as a 3D transformation problem with zero (0) values assigned for the z-components of both target and source points. The efficiency of the new algorithm is presented with the numerical examples and comparisons with the results of the previous studies which use the same data set. Simulation experiments for the evaluation and comparison of the proposed and the conventional weighted LS (WLS) method is also presented.

  14. A fast identification algorithm for Box-Cox transformation based radial basis function neural network.

    Science.gov (United States)

    Hong, Xia

    2006-07-01

    In this letter, a Box-Cox transformation-based radial basis function (RBF) neural network is introduced using the RBF neural network to represent the transformed system output. Initially a fixed and moderate sized RBF model base is derived based on a rank revealing orthogonal matrix triangularization (QR decomposition). Then a new fast identification algorithm is introduced using Gauss-Newton algorithm to derive the required Box-Cox transformation, based on a maximum likelihood estimator. The main contribution of this letter is to explore the special structure of the proposed RBF neural network for computational efficiency by utilizing the inverse of matrix block decomposition lemma. Finally, the Box-Cox transformation-based RBF neural network, with good generalization and sparsity, is identified based on the derived optimal Box-Cox transformation and a D-optimality-based orthogonal forward regression algorithm. The proposed algorithm and its efficacy are demonstrated with an illustrative example in comparison with support vector machine regression.

  15. Conducting polymer based biomolecular electronic devices

    Indian Academy of Sciences (India)

    Conducting polymers; LB films; biosensor microactuators; monolayers. ... have been projected for applications for a wide range of biomolecular electronic devices such as optical, electronic, drug-delivery, memory and biosensing devices.

  16. Flexible and Cellulose-based Organic Electronics

    OpenAIRE

    Edberg, Jesper

    2017-01-01

    Organic electronics is the study of organic materials with electronic functionality and the applications of such materials. In the 1970s, the discovery that polymers can be made electrically conductive led to an explosion within this field which has continued to grow year by year. One of the attractive features of organic electronic materials is their inherent mechanical flexibility, which has led to the development of numerous flexible electronics technologies such as organic light emitting ...

  17. Discrete linear canonical transforms based on dilated Hermite functions.

    Science.gov (United States)

    Pei, Soo-Chang; Lai, Yun-Chiu

    2011-08-01

    Linear canonical transform (LCT) is very useful and powerful in signal processing and optics. In this paper, discrete LCT (DLCT) is proposed to approximate LCT by utilizing the discrete dilated Hermite functions. The Wigner distribution function is also used to investigate DLCT performances in the time-frequency domain. Compared with the existing digital computation of LCT, our proposed DLCT possess additivity and reversibility properties with no oversampling involved. In addition, the length of input/output signals will not be changed before and after the DLCT transformations, which is consistent with the time-frequency area-preserving nature of LCT; meanwhile, the proposed DLCT has very good approximation of continuous LCT.

  18. Effects of finite pulse width on two-dimensional Fourier transform electron spin resonance.

    Science.gov (United States)

    Liang, Zhichun; Crepeau, Richard H; Freed, Jack H

    2005-12-01

    Two-dimensional (2D) Fourier transform ESR techniques, such as 2D-ELDOR, have considerably improved the resolution of ESR in studies of molecular dynamics in complex fluids such as liquid crystals and membrane vesicles and in spin labeled polymers and peptides. A well-developed theory based on the stochastic Liouville equation (SLE) has been successfully employed to analyze these experiments. However, one fundamental assumption has been utilized to simplify the complex analysis, viz. the pulses have been treated as ideal non-selective ones, which therefore provide uniform irradiation of the whole spectrum. In actual experiments, the pulses are of finite width causing deviations from the theoretical predictions, a problem that is exacerbated by experiments performed at higher frequencies. In the present paper we provide a method to deal with the full SLE including the explicit role of the molecular dynamics, the spin Hamiltonian and the radiation field during the pulse. The computations are rendered more manageable by utilizing the Trotter formula, which is adapted to handle this SLE in what we call a "Split Super-Operator" method. Examples are given for different motional regimes, which show how 2D-ELDOR spectra are affected by the finite pulse widths. The theory shows good agreement with 2D-ELDOR experiments performed as a function of pulse width.

  19. Analysis of transformations of the ultrafast electron transfer photoreaction mechanism in liquid solutions by the rate distribution approach.

    Science.gov (United States)

    Kuzmin, Michael G; Soboleva, Irina V

    2014-05-01

    Representation of the experimental reaction kinetics in the form of rate distribution is shown to be an effective method for the analysis of the mechanisms of these reactions and for comparisons of the kinetics with QC calculations, as well as with the experimental data on the medium mobility. The rate constant distribution function P(k) can be obtained directly from the experimental kinetics N(t) by an inverse Laplace transform. The application of this approach to kinetic data for several excited-state electron transfer reactions reveals the transformations of their rate control factors in the time domain of 1-1000 ps. In neat electron donating solvents two components are observed. The fastest component (k > 1 ps(-1)) was found to be controlled by the fluctuations of the overall electronic coupling matrix element, involving all the reactant molecules, located inside the interior of the solvent shell, rather than for specific pairs of reactant molecules. The slower component (1 > k > 0.1 ps(-1)) is controlled by the medium reorganization (longitudinal relaxation times, τL). A substantial contribution from the non-stationary diffusion controlled reaction is observed in diluted solutions ([Q] transformation of the rate control factors in the course of the reactions.

  20. Transformations Based on Continuous Piecewise-Affine Velocity Fields

    DEFF Research Database (Denmark)

    Freifeld, Oren; Hauberg, Søren; Batmanghelich, Kayhan

    2017-01-01

    We propose novel finite-dimensional spaces of well-behaved transformations. The latter are obtained by (fast and highly-accurate) integration of continuous piecewise-affine velocity fields. The proposed method is simple yet highly expressive, effortlessly handles optional constraints (e.g., volum...

  1. Electrocardiogram de-noising based on forward wavelet transform ...

    Indian Academy of Sciences (India)

    Ratio (SNR) and Mean Square Error (MSE) computations showed that our proposed ... This technique permits to cancel noises and retain the informa- tion of the ... Wavelet analysis is used for transforming the signal under investigation into joined temporal and ... introduced the BWT in our proposed ECG de-noising system.

  2. Analytic discrete cosine harmonic wavelet transform based OFDM ...

    Indian Academy of Sciences (India)

    ADCHWT_OFDM) has been proposed in this paper. Analytic DCHWT has been realized by applying DCHWT to the original signal and to its Hilbert transform. ADCHWT has been found to be computationally efficient and very effective in improving ...

  3. An efficient visual saliency detection model based on Ripplet transform

    Indian Academy of Sciences (India)

    A Diana Andrushia

    human visual attention models is still not well investigated. ... Ripplet transform; visual saliency model; Receiver Operating Characteristics (ROC); .... proposed method has the same resolution as that of an input ... regions are obtained, which are independent of their sizes. ..... impact than those far away from the attention.

  4. MR-guided stereotactic neurosurgery-comparison of fiducial-based and anatomical landmark transformation approaches

    International Nuclear Information System (INIS)

    Hunsche, S; Sauner, D; Maarouf, M; Hoevels, M; Luyken, K; Schulte, O; Lackner, K; Sturm, V; Treuer, H

    2004-01-01

    For application in magnetic resonance (MR) guided stereotactic neurosurgery, two methods for transformation of MR-image coordinates in stereotactic, frame-based coordinates exist: the direct stereotactic fiducial-based transformation method and the indirect anatomical landmark method. In contrast to direct stereotactic MR transformation, indirect transformation is based on anatomical landmark coregistration of stereotactic computerized tomography and non-stereotactic MR images. In a patient study, both transformation methods have been investigated with visual inspection and mutual information analysis. Comparison was done for our standard imaging protocol, including t2-weighted spin-echo as well as contrast enhanced t1-weighted gradient-echo imaging. For t2-weighted spin-echo imaging, both methods showed almost similar and satisfying performance with a small, but significant advantage for fiducial-based transformation. In contrast, for t1-weighted gradient-echo imaging with more geometric distortions due to field inhomogenities and gradient nonlinearity than t2-weighted spin-echo imaging, mainly caused by a reduced bandwidth per pixel, anatomical landmark transformation delivered markedly better results. Here, fiducial-based transformation yielded results which are intolerable for stereotactic neurosurgery. Mean Euclidian distances between both transformation methods were 0.96 mm for t2-weighted spin-echo and 1.67 mm for t1-weighted gradient-echo imaging. Maximum deviations were 1.72 mm and 3.06 mm, respectively

  5. MR-guided stereotactic neurosurgery-comparison of fiducial-based and anatomical landmark transformation approaches

    Energy Technology Data Exchange (ETDEWEB)

    Hunsche, S [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Sauner, D [Institute for Diagnostic and Interventional Radiology, Friedrich-Schiller-University of Jena, Jena (Germany); Maarouf, M [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Hoevels, M [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Luyken, K [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Schulte, O [Department of Radiology, University of Cologne, Cologne (Germany); Lackner, K [Department of Radiology, University of Cologne, Cologne (Germany); Sturm, V [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany); Treuer, H [Department of Stereotaxy and Functional Neurosurgery, University of Cologne, Cologne (Germany)

    2004-06-21

    For application in magnetic resonance (MR) guided stereotactic neurosurgery, two methods for transformation of MR-image coordinates in stereotactic, frame-based coordinates exist: the direct stereotactic fiducial-based transformation method and the indirect anatomical landmark method. In contrast to direct stereotactic MR transformation, indirect transformation is based on anatomical landmark coregistration of stereotactic computerized tomography and non-stereotactic MR images. In a patient study, both transformation methods have been investigated with visual inspection and mutual information analysis. Comparison was done for our standard imaging protocol, including t2-weighted spin-echo as well as contrast enhanced t1-weighted gradient-echo imaging. For t2-weighted spin-echo imaging, both methods showed almost similar and satisfying performance with a small, but significant advantage for fiducial-based transformation. In contrast, for t1-weighted gradient-echo imaging with more geometric distortions due to field inhomogenities and gradient nonlinearity than t2-weighted spin-echo imaging, mainly caused by a reduced bandwidth per pixel, anatomical landmark transformation delivered markedly better results. Here, fiducial-based transformation yielded results which are intolerable for stereotactic neurosurgery. Mean Euclidian distances between both transformation methods were 0.96 mm for t2-weighted spin-echo and 1.67 mm for t1-weighted gradient-echo imaging. Maximum deviations were 1.72 mm and 3.06 mm, respectively.

  6. [Continuum based fast Fourier transform processing of infrared spectrum].

    Science.gov (United States)

    Liu, Qing-Jie; Lin, Qi-Zhong; Wang, Qin-Jun; Li, Hui; Li, Shuai

    2009-12-01

    To recognize ground objects with infrared spectrum, high frequency noise removing is one of the most important phases in spectrum feature analysis and extraction. A new method for infrared spectrum preprocessing was given combining spectrum continuum processing and Fast Fourier Transform (CFFT). Continuum was firstly removed from the noise polluted infrared spectrum to standardize hyper-spectra. Then the spectrum was transformed into frequency domain (FD) with fast Fourier transform (FFT), separating noise information from target information After noise eliminating from useful information with a low-pass filter, the filtered FD spectrum was transformed into time domain (TD) with fast Fourier inverse transform. Finally the continuum was recovered to the spectrum, and the filtered infrared spectrum was achieved. Experiment was performed for chlorite spectrum in USGS polluted with two kinds of simulated white noise to validate the filtering ability of CFFT by contrast with cubic function of five point (CFFP) in time domain and traditional FFT in frequency domain. A circle of CFFP has limited filtering effect, so it should work much with more circles and consume more time to achieve better filtering result. As for conventional FFT, Gibbs phenomenon has great effect on preprocessing result at edge bands because of special character of rock or mineral spectra, while works well at middle bands. Mean squared error of CFFT is 0. 000 012 336 with cut-off frequency of 150, while that of FFT and CFFP is 0. 000 061 074 with cut-off frequency of 150 and 0.000 022 963 with 150 working circles respectively. Besides the filtering result of CFFT can be improved by adjusting the filter cut-off frequency, and has little effect on working time. The CFFT method overcomes the Gibbs problem of FFT in spectrum filtering, and can be more convenient, dependable, and effective than traditional TD filter methods.

  7. Tunable arbitrary unitary transformer based on multiple sections of multicore fibers with phase control.

    Science.gov (United States)

    Zhou, Junhe; Wu, Jianjie; Hu, Qinsong

    2018-02-05

    In this paper, we propose a novel tunable unitary transformer, which can achieve arbitrary discrete unitary transforms. The unitary transformer is composed of multiple sections of multi-core fibers with closely aligned coupled cores. Phase shifters are inserted before and after the sections to control the phases of the waves in the cores. A simple algorithm is proposed to find the optimal phase setup for the phase shifters to realize the desired unitary transforms. The proposed device is fiber based and is particularly suitable for the mode division multiplexing systems. A tunable mode MUX/DEMUX for a three-mode fiber is designed based on the proposed structure.

  8. Induced over voltage test on transformers using enhanced Z-source inverter based circuit

    Science.gov (United States)

    Peter, Geno; Sherine, Anli

    2017-09-01

    The normal life of a transformer is well above 25 years. The economical operation of the distribution system has its roots in the equipments being used. The economy being such, that it is financially advantageous to replace transformers with more than 15 years of service in the second perennial market. Testing of transformer is required, as its an indication of the extent to which a transformer can comply with the customers specified requirements and the respective standards (IEC 60076-3). In this paper, induced over voltage testing on transformers using enhanced Z source inverter is discussed. Power electronic circuits are now essential for a whole array of industrial electronic products. The bulky motor generator set, which is used to generate the required frequency to conduct the induced over voltage testing of transformers is nowadays replaced by static frequency converter. First conventional Z-source inverter, and second an enhanced Z source inverter is being used to generate the required voltage and frequency to test the transformer for induced over voltage test, and its characteristics is analysed.

  9. Oscillation mode transformation of edge magnetoplasmons in two-dimensional electron system on liquid-helium surface

    International Nuclear Information System (INIS)

    Yamanaka, Shuji; Yayama, Hideki; Arai, Toshikazau; Anju Sawada, Anju; Fukuda, Akira

    2013-01-01

    We measured the resonance spectra of edge magnetoplasmon (EMP) oscillations in a two-dimensional (2D) electron system located on a liquid-helium surface below 1.1 K. Systematic measurements of the resonance frequency and the damping rate as a function of the lateral confinement electric field strength shows clear evidence of the oscillation mode transformation. A pronounced change corresponding to the mode transformation was observed in the damping rate. When 2D electrons are confined in a strong lateral electric field, the damping is weak. As the lateral confinement electric field is reduced below a certain threshold value, an abrupt enhancement of the damping rate is observed. We hypothesize that the weak damping mode in the strong lateral confinement electric field is the compressive density oscillation of the electrons near the edge (conventional EMP) and the strong damping mode in the weak confinement field is the coupled mode of conventional EMP and the boundary displacement wave (BDW). The observation of the strong damping in the BDW-EMP coupled mode is a manifestation of the nearly incompressible feature of strongly interacting classical electrons, which agrees with earlier theoretical predictions.

  10. Wire Position Monitoring with FPGA based Electronics

    International Nuclear Information System (INIS)

    Eddy, N.; Lysenko, O.

    2009-01-01

    This fall the first Tesla-style cryomodule cooldown test is being performed at Fermilab. Instrumentation department is preparing the electronics to handle the data from a set of wire position monitors (WPMs). For simulation purposes a prototype pipe with a WMP has been developed and built. The system is based on the measurement of signals induced in pickups by 320 MHz signal carried by a wire through the WPM. The wire is stretched along the pipe with a tensioning load of 9.07 kg. The WPM consists of four 50 (Omega) striplines spaced 90 o apart. FPGA based digitizer scans the WPM and transmits the data to a PC via VME interface. The data acquisition is based on the PC running LabView. In order to increase the accuracy and convenience of the measurements some modifications were required. The first is implementation of an average and decimation filter algorithm in the integrator operation in the FPGA. The second is the development of alternative tool for WPM measurements in the PC. The paper describes how these modifications were performed and test results of a new design. The last cryomodule generation has a single chain of seven WPMs (placed in critical positions: at each end, at the three posts and between the posts) to monitor a cold mass displacement during cooldown. The system was developed in Italy in collaboration with DESY. Similar developments have taken place at Fermilab in the frame of cryomodules construction for SCRF research. This fall preliminary cryomodule cooldown test is being performed. In order to prepare an appropriate electronic system for the test a prototype pipe with a WMP has been developed and built, figure 1. The system is based on the measurement of signals induced in pickups by 320 MHz signal carried by a wire through the WPM. The 0.5 mm diameter Cu wire is stretched along the pipe with a tensioning load of 9.07 kg and has a length of 1.1 m. The WPM consists of four 50 (Omega) striplines spaced 90 o apart. An FPGA based digitizer

  11. REMOTELY SENSEDC IMAGE COMPRESSION BASED ON WAVELET TRANSFORM

    Directory of Open Access Journals (Sweden)

    Heung K. Lee

    1996-06-01

    Full Text Available In this paper, we present an image compression algorithm that is capable of significantly reducing the vast mount of information contained in multispectral images. The developed algorithm exploits the spectral and spatial correlations found in multispectral images. The scheme encodes the difference between images after contrast/brightness equalization to remove the spectral redundancy, and utilizes a two-dimensional wavelet trans-form to remove the spatial redundancy. The transformed images are than encoded by hilbert-curve scanning and run-length-encoding, followed by huffman coding. We also present the performance of the proposed algorithm with KITSAT-1 image as well as the LANDSAT MultiSpectral Scanner data. The loss of information is evaluated by peak signal to noise ratio (PSNR and classification capability.

  12. Complexity estimates based on integral transforms induced by computational units

    Czech Academy of Sciences Publication Activity Database

    Kůrková, Věra

    2012-01-01

    Roč. 33, September (2012), s. 160-167 ISSN 0893-6080 R&D Projects: GA ČR GAP202/11/1368 Institutional research plan: CEZ:AV0Z10300504 Institutional support: RVO:67985807 Keywords : neural networks * estimates of model complexity * approximation from a dictionary * integral transforms * norms induced by computational units Subject RIV: IN - Informatics, Computer Science Impact factor: 1.927, year: 2012

  13. An Alternative Estimation of Market Volatility based on Fuzzy Transform

    OpenAIRE

    Troiano, Luigi; Villa, Elena Mejuto; Kriplani, Pravesh

    2017-01-01

    Realization of uncertainty of prices is captured by volatility, that is the tendency of prices to vary along a period of time. This is generally measured as standard deviation of daily returns. In this paper we propose and investigate the application of fuzzy transform and its inverse as an alternative measure of volatility. The measure obtained is compatible with the definition of risk measure given by Luce. A comparison with standard definition is performed by considering the NIFTY 50 stock...

  14. INVESTIGATING SHAPE REPRESENTATION USING SENSITIVITY TO PART- AND AXIS-BASED TRANSFORMATIONS

    OpenAIRE

    Denisova, Kristina; Feldman, Jacob; Su, Xiaotao; Singh, Manish

    2016-01-01

    Part -and axis-based approaches organize shape representations in terms of simple parts and their spatial relationships. Shape transformations that alter qualitative part structure have been shown to be more detectable than those that preserve it. We compared sensitivity to various transformations that change quantitative properties of parts and their spatial relationships, while preserving qualitative part structure. Shape transformations involving changes in length, width, curvature, orient...

  15. Electronic structure of hybrid interfaces for polymer-based electronics

    International Nuclear Information System (INIS)

    Fahlman, M; Crispin, A; Crispin, X; Henze, S K M; Jong, M P de; Osikowicz, W; Tengstedt, C; Salaneck, W R

    2007-01-01

    The fundamentals of the energy level alignment at anode and cathode electrodes in organic electronics are described. We focus on two different models that treat weakly interacting organic/metal (and organic/organic) interfaces: the induced density of interfacial states model and the so-called integer charge transfer model. The two models are compared and evaluated, mainly using photoelectron spectroscopy data of the energy level alignment of conjugated polymers and molecules at various organic/metal and organic/organic interfaces. We show that two different alignment regimes are generally observed: (i) vacuum level alignment, which corresponds to the lack of vacuum level offsets (Schottky-Mott limit) and hence the lack of charge transfer across the interface, and (ii) Fermi level pinning where the resulting work function of an organic/metal and organic/organic bilayer is independent of the substrate work function and an interface dipole is formed due to charge transfer across the interface. We argue that the experimental results are best described by the integer charge transfer model which predicts the vacuum level alignment when the substrate work function is above the positive charge transfer level and below the negative charge transfer level of the conjugated material. The model further predicts Fermi level pinning to the positive (negative) charge transfer level when the substrate work function is below (above) the positive (negative) charge transfer level. The nature of the integer charge transfer levels depend on the materials system: for conjugated large molecules and polymers, the integer charge transfer states are polarons or bipolarons; for small molecules' highest occupied and lowest unoccupied molecular orbitals and for crystalline systems, the relevant levels are the valence and conduction band edges. Finally, limits and further improvements to the integer charge transfer model are discussed as well as the impact on device design. (topical review)

  16. Reversibly Bistable Flexible Electronics

    KAUST Repository

    Alfaraj, Nasir

    2015-01-01

    Introducing the notion of transformational silicon electronics has paved the way for integrating various applications with silicon-based, modern, high-performance electronic circuits that are mechanically flexible and optically semitransparent

  17. Spectrums Transform Operators in Bases of Fourier and Walsh Functions

    Directory of Open Access Journals (Sweden)

    V. V. Syuzev

    2017-01-01

    Full Text Available The problems of synthesis of the efficient algorithms for digital processing of discrete signals require transforming the signal spectra from one basis system into other. The rational solution to this problem is to construct the Fourier kernel, which is a spectrum of some basis functions, according to the system of functions of the other basis. However, Fourier kernel properties are not equally studied and described for all basis systems of practical importance. The article sets a task and presents an original way to solve the problem of mutual transformation of trigonometric Fourier spectrum into Walsh spectrum of different basis systems.The relevance of this theoretical and applied problem is stipulated, on the one hand, by the prevalence of trigonometric Fourier basis for harmonic representation of digital signals, and, on the other hand, by the fact that Walsh basis systems allow us to have efficient algorithms to simulate signals. The problem solution is achieved through building the Fourier kernel of a special structure that allows us to establish independent groups of Fourier and Walsh spectrum coefficients for further reducing the computational complexity of the transform algorithms.The article analyzes the properties of the system of trigonometric Fourier functions and shows its completeness. Considers the Walsh function basis systems in three versions, namely those of Hadamard, Paley, and Hartmut giving different ordering and analytical descriptions of the functions that make up the basis. Proves a completeness of these systems.Sequentially, for each of the three Walsh systems the analytical curves for the Fourier kernel components are obtained, and Fourier kernel themselves are built with binary rational number of samples of basis functions. The kernels are presented in matrix form and, as an example, recorded for a particular value of the discrete interval of N, equal to 8. The analysis spectral coefficients of the Fourier kernel

  18. Correlated structural and electronic phase transformations in transition metal chalcogenide under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Li, Chunyu, E-mail: licy@hpstar.ac.cn, E-mail: yanhao@hpstar.ac.cn; Ke, Feng; Yu, Zhenhai; Chen, Zhiqiang; Yan, Hao, E-mail: licy@hpstar.ac.cn, E-mail: yanhao@hpstar.ac.cn [Center for High Pressure Science and Technology Advanced Research, Shanghai 201203 (China); Hu, Qingyang [Center for High Pressure Science and Technology Advanced Research, Shanghai 201203 (China); Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC 20015 (United States); Zhao, Jinggeng [Natural Science Research Center, Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080 (China)

    2016-04-07

    Here, we report comprehensive studies on the high-pressure structural and electrical transport properties of the layered transition metal chalcogenide (Cr{sub 2}S{sub 3}) up to 36.3 GPa. A structural phase transition was observed in the rhombohedral Cr{sub 2}S{sub 3} near 16.5 GPa by the synchrotron angle dispersive X-ray diffraction measurement using a diamond anvil cell. Through in situ resistance measurement, the electric resistance value was detected to decrease by an order of three over the pressure range of 7–15 GPa coincided with the structural phase transition. Measurements on the temperature dependence of resistivity indicate that it is a semiconductor-to-metal transition in nature. The results were also confirmed by the electronic energy band calculations. Above results may shed a light on optimizing the performance of Cr{sub 2}S{sub 3} based applications under extreme conditions.

  19. Electron Source based on Superconducting RF

    Science.gov (United States)

    Xin, Tianmu

    High-bunch-charge photoemission electron-sources operating in a Continuous Wave (CW) mode can provide high peak current as well as the high average current which are required for many advanced applications of accelerators facilities, for example, electron coolers for hadron beams, electron-ion colliders, and Free-Electron Lasers (FELs). Superconducting Radio Frequency (SRF) has many advantages over other electron-injector technologies, especially when it is working in CW mode as it offers higher repetition rate. An 112 MHz SRF electron photo-injector (gun) was developed at Brookhaven National Laboratory (BNL) to produce high-brightness and high-bunch-charge bunches for electron cooling experiments. The gun utilizes a Quarter-Wave Resonator (QWR) geometry for a compact structure and improved electron beam dynamics. The detailed RF design of the cavity, fundamental coupler and cathode stalk are presented in this work. A GPU accelerated code was written to improve the speed of simulation of multipacting, an important hurdle the SRF structure has to overcome in various locations. The injector utilizes high Quantum Efficiency (QE) multi-alkali photocathodes (K2CsSb) for generating electrons. The cathode fabrication system and procedure are also included in the thesis. Beam dynamic simulation of the injector was done with the code ASTRA. To find the optimized parameters of the cavities and beam optics, the author wrote a genetic algorithm Python script to search for the best solution in this high-dimensional parameter space. The gun was successfully commissioned and produced world record bunch charge and average current in an SRF photo-injector.

  20. Communication: Multireference equation of motion coupled cluster: A transform and diagonalize approach to electronic structure

    Czech Academy of Sciences Publication Activity Database

    Nooijen, M.; Demel, Ondřej; Datta, D.; Kong, L.; Shamasundar, K. R.; Lotrich, V.; Huntington, L. M.; Neese, F.

    2014-01-01

    Roč. 140, č. 8 (2014), 081102 ISSN 0021-9606 R&D Projects: GA ČR GPP208/10/P041; GA ČR GAP208/11/2222 Institutional support: RVO:61388955 Keywords : Electronic states * Electronic structure * Equations of motion Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.952, year: 2014

  1. 2D non-separable linear canonical transform (2D-NS-LCT) based cryptography

    Science.gov (United States)

    Zhao, Liang; Muniraj, Inbarasan; Healy, John J.; Malallah, Ra'ed; Cui, Xiao-Guang; Ryle, James P.; Sheridan, John T.

    2017-05-01

    The 2D non-separable linear canonical transform (2D-NS-LCT) can describe a variety of paraxial optical systems. Digital algorithms to numerically evaluate the 2D-NS-LCTs are not only important in modeling the light field propagations but also of interest in various signal processing based applications, for instance optical encryption. Therefore, in this paper, for the first time, a 2D-NS-LCT based optical Double-random- Phase-Encryption (DRPE) system is proposed which offers encrypting information in multiple degrees of freedom. Compared with the traditional systems, i.e. (i) Fourier transform (FT); (ii) Fresnel transform (FST); (iii) Fractional Fourier transform (FRT); and (iv) Linear Canonical transform (LCT), based DRPE systems, the proposed system is more secure and robust as it encrypts the data with more degrees of freedom with an augmented key-space.

  2. Fast parallel approach for 2-D DHT-based real-valued discrete Gabor transform.

    Science.gov (United States)

    Tao, Liang; Kwan, Hon Keung

    2009-12-01

    Two-dimensional fast Gabor transform algorithms are useful for real-time applications due to the high computational complexity of the traditional 2-D complex-valued discrete Gabor transform (CDGT). This paper presents two block time-recursive algorithms for 2-D DHT-based real-valued discrete Gabor transform (RDGT) and its inverse transform and develops a fast parallel approach for the implementation of the two algorithms. The computational complexity of the proposed parallel approach is analyzed and compared with that of the existing 2-D CDGT algorithms. The results indicate that the proposed parallel approach is attractive for real time image processing.

  3. Broadband Impedance Transformer Based on Asymmetric Coupled Transmission Lines in Nonhomogeneous Medium

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Krozer, Viktor; Meincke, Peter

    2007-01-01

    A new broadband quarter-wavelength impedance transformer based on an asymmetric coupled line section is presented. The bandwidth of the coupled line transformer is extended with the help of an interconnecting transmission line. An analytical model for the transformer is developed. The analysis...... of the structure reveals that a fractional bandwidth of more than 100% at –20 dB reflection level can be achieved with such a structure. An experimental transformer circuit has been designed, fabricated and tested. Theoretical and experimental results are fair agreement and confirm the established theory...

  4. Identification Method of Mud Shale Fractures Base on Wavelet Transform

    Science.gov (United States)

    Xia, Weixu; Lai, Fuqiang; Luo, Han

    2018-01-01

    In recent years, inspired by seismic analysis technology, a new method for analysing mud shale fractures oil and gas reservoirs by logging properties has emerged. By extracting the high frequency attribute of the wavelet transform in the logging attribute, the formation information hidden in the logging signal is extracted, identified the fractures that are not recognized by conventional logging and in the identified fracture segment to show the “cycle jump”, “high value”, “spike” and other response effect is more obvious. Finally formed a complete wavelet denoising method and wavelet high frequency identification fracture method.

  5. Human Body Image Edge Detection Based on Wavelet Transform

    Institute of Scientific and Technical Information of China (English)

    李勇; 付小莉

    2003-01-01

    Human dresses are different in thousands way.Human body image signals have big noise, a poor light and shade contrast and a narrow range of gray gradation distribution. The application of a traditional grads method or gray method to detect human body image edges can't obtain satisfactory results because of false detections and missed detections. According to tte peculiarity of human body image, dyadic wavelet transform of cubic spline is successfully applied to detect the face and profile edges of human body image and Mallat algorithm is used in the wavelet decomposition in this paper.

  6. Polarization splitter and polarization rotator designs based on transformation optics.

    Science.gov (United States)

    Kwon, Do-Hoon; Werner, Douglas H

    2008-11-10

    The transformation optics technique is employed in this paper to design two optical devices - a two-dimensional polarization splitter and a three-dimensional polarization rotator for propagating beams. The polarization splitter translates the TM- and the TE-polarized components of an incident beam in opposite directions (i.e., shifted up or shifted down). The polarization rotator rotates the polarization state of an incoming beam by an arbitrary angle. Both optical devices are reflectionless at the entry and exit interfaces. Design details and full-wave simulation results are provided.

  7. Calculation Scheme Based on a Weighted Primitive: Application to Image Processing Transforms

    Directory of Open Access Journals (Sweden)

    Gregorio de Miguel Casado

    2007-01-01

    Full Text Available This paper presents a method to improve the calculation of functions which specially demand a great amount of computing resources. The method is based on the choice of a weighted primitive which enables the calculation of function values under the scope of a recursive operation. When tackling the design level, the method shows suitable for developing a processor which achieves a satisfying trade-off between time delay, area costs, and stability. The method is particularly suitable for the mathematical transforms used in signal processing applications. A generic calculation scheme is developed for the discrete fast Fourier transform (DFT and then applied to other integral transforms such as the discrete Hartley transform (DHT, the discrete cosine transform (DCT, and the discrete sine transform (DST. Some comparisons with other well-known proposals are also provided.

  8. Dissociating object-based from egocentric transformations in mental body rotation: effect of stimuli size.

    Science.gov (United States)

    Habacha, Hamdi; Moreau, David; Jarraya, Mohamed; Lejeune-Poutrain, Laure; Molinaro, Corinne

    2018-01-01

    The effect of stimuli size on the mental rotation of abstract objects has been extensively investigated, yet its effect on the mental rotation of bodily stimuli remains largely unexplored. Depending on the experimental design, mentally rotating bodily stimuli can elicit object-based transformations, relying mainly on visual processes, or egocentric transformations, which typically involve embodied motor processes. The present study included two mental body rotation tasks requiring either a same-different or a laterality judgment, designed to elicit object-based or egocentric transformations, respectively. Our findings revealed shorter response times for large-sized stimuli than for small-sized stimuli only for greater angular disparities, suggesting that the more unfamiliar the orientations of the bodily stimuli, the more stimuli size affected mental processing. Importantly, when comparing size transformation times, results revealed different patterns of size transformation times as a function of angular disparity between object-based and egocentric transformations. This indicates that mental size transformation and mental rotation proceed differently depending on the mental rotation strategy used. These findings are discussed with respect to the different spatial manipulations involved during object-based and egocentric transformations.

  9. The Need for Transformational Leadership in Singapore's School-Based Reform

    Science.gov (United States)

    Retna, Kala S.; Ng, Pak Tee

    2009-01-01

    In Singapore, "decentralization" and "school-based reforms" are key words within the current education reform agenda. This article argues that a key success factor in this agenda is transformational leadership in school. With more autonomy given to the school, transformational leadership at the school level will facilitate the…

  10. Crystallographically based model for transformation-induced plasticity in multiphase carbon steels

    NARCIS (Netherlands)

    Tjahjanto, D.D.; Turteltaub, S.; Suiker, A.S.J.

    2007-01-01

    The microstructure of multiphase steels assisted by transformation-induced plasticity consists of grains of retained austenite embedded in a ferrite-based matrix. Upon mechanical loading, retained austenite may transform into martensite, as a result of which plastic deformations are induced in the

  11. Crystallographically based model for transformation-induced plasticity in multiphase carbon steels

    NARCIS (Netherlands)

    Tjahjanto, D.D.; Turteltaub, S.R.; Suiker, A.S.J.

    2008-01-01

    The microstructure of multiphase steels assisted by transformation-induced plasticity consists of grains of retained austenite embedded in a ferrite-based matrix. Upon mechanical loading, retained austenite may transform into martensite, as a result of which plastic deformations are induced in the

  12. Coordinated Voltage Control Scheme for SEIG-Based Wind Park Utilizing Substation STATCOM and ULTC Transformer

    DEFF Research Database (Denmark)

    S. El Moursi, Mohamed; Bak-Jensen, Birgitte; Abdel-Rahman, Mansour Hassan

    2011-01-01

    and optimal tracking secondary voltage control for wind parks based on self-excited induction generators which comprise STATCOM and under-load tap changer (ULTC) substation transformers. The voltage controllers for the STATCOM and ULTC transformer are coordinated and ensure the voltage support. In steady...

  13. Transformational Electronics: Towards Flexible Low-Cost High Mobility Channel Materials

    KAUST Repository

    Nassar, Joanna M.

    2014-05-01

    For the last four decades, Si CMOS technology has been advancing with Moore’s law prediction, working itself down to the sub-20 nm regime. However, fundamental problems and limitations arise with the down-scaling of transistors and thus new innovations needed to be discovered in order to further improve device performance without compromising power consumption and size. Thus, a lot of studies have focused on the development of new CMOS compatible architectures as well as the discovery of new high mobility channel materials that will allow further miniaturization of CMOS transistors and improvement of device performance. Pushing the limits even further, flexible and foldable electronics seem to be the new attractive topic. By being able to make our devices flexible through a CMOS compatible process, one will be able to integrate hundreds of billions of more transistors in a small volumetric space, allowing to increase the performance and speed of our electronics all together with making things thinner, lighter, smaller and even interactive with the human skin. Thus, in this thesis, we introduce for the first time a cost-effective CMOS compatible approach to make high-k/metal gate devices on flexible Germanium (Ge) and Silicon-Germanium (SiGe) platforms. In the first part, we will look at the various approaches in the literature that has been developed to get flexible platforms, as well as we will give a brief overview about epitaxial growth of Si1-xGex films. We will also examine the electrical properties of the Si1-xGex alloys up to Ge (x=1) and discuss how strain affects the band structure diagram, and thus the mobility of the material. We will also review the material growth properties as well as the state-of-the-art results on high mobility metal-oxide semiconductor capacitors (MOSCAPs) using strained SiGe films. Then, we will introduce the flexible process that we have developed, based on a cost-effective “trench-protect-release-reuse” approach, utilizing

  14. Process identification method based on the Z transformation; Methode d'identification de processus par la transformation en Z

    Energy Technology Data Exchange (ETDEWEB)

    Zwingelstein, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-07-01

    A simple method is described for identifying the transfer function of a linear retard-less system, based on the inversion of the Z transformation of the transmittance using a computer. It is assumed in this study that the signals at the entrance and at the exit of the circuit considered are of the deterministic type. The study includes: the theoretical principle of the inversion of the Z transformation, details about programming simulation, and identification of filters whose degrees vary from the first to the fifth order. (authors) [French] On decrit une methode simple d'identification de fonction de transfert d'un systeme lineaire sans retard, qui repose sur l'inversion de la transformee en Z de la transmittance a l'aide d'un calculateur. On suppose dans cette etude, que les signaux a l'entree et a la sortie du circuit considere sont de type deterministe. L'etude comporte: le principe theorique de l'inversion de la transformation en Z, les details de la programmation, la simulation et l'identification de filtres dont le degre varie du premier au cinquieme ordre. (auteurs)

  15. Plasmonically enhanced hot electron based photovoltaic device.

    Science.gov (United States)

    Atar, Fatih B; Battal, Enes; Aygun, Levent E; Daglar, Bihter; Bayindir, Mehmet; Okyay, Ali K

    2013-03-25

    Hot electron photovoltaics is emerging as a candidate for low cost and ultra thin solar cells. Plasmonic means can be utilized to significantly boost device efficiency. We separately form the tunneling metal-insulator-metal (MIM) junction for electron collection and the plasmon exciting MIM structure on top of each other, which provides high flexibility in plasmonic design and tunneling MIM design separately. We demonstrate close to one order of magnitude enhancement in the short circuit current at the resonance wavelengths.

  16. Fault diagnosis model for power transformers based on information fusion

    Science.gov (United States)

    Dong, Ming; Yan, Zhang; Yang, Li; Judd, Martin D.

    2005-07-01

    Methods used to assess the insulation status of power transformers before they deteriorate to a critical state include dissolved gas analysis (DGA), partial discharge (PD) detection and transfer function techniques, etc. All of these approaches require experience in order to correctly interpret the observations. Artificial intelligence (AI) is increasingly used to improve interpretation of the individual datasets. However, a satisfactory diagnosis may not be obtained if only one technique is used. For example, the exact location of PD cannot be predicted if only DGA is performed. However, using diverse methods may result in different diagnosis solutions, a problem that is addressed in this paper through the introduction of a fuzzy information infusion model. An inference scheme is proposed that yields consistent conclusions and manages the inherent uncertainty in the various methods. With the aid of information fusion, a framework is established that allows different diagnostic tools to be combined in a systematic way. The application of information fusion technique for insulation diagnostics of transformers is proved promising by means of examples.

  17. Polarizing Beam Splitter: A New Approach Based on Transformation Optics

    Science.gov (United States)

    Mueller, Jonhatan; Wegener, Martin

    Standard optical elements (e.g. lenses, prisms) are mostly designed of piecewise homogeneous and isotropic dielectrics. However, in theory one has far more possibilities to influence electromagnetic waves, namely all the components of the permittivity and permeability tensors. In the past few years, on the one hand, new micro fabrication methods allowed for new freedom in controlling of the optical parameters using so called artificial metamaterials. On the other hand, the theory of transformation optics has given a somewhat intuitive approach for the design of such structures. The most popular feature of this kind is certainly optical cloaking (i.e. [1,2]). However, the full capabilities of other transformation optical devices are far from being fully explored. In my work, I focused on pure dielectric structures in a non-resonant and therefore non-lossy regime. Although the relative permittivity one can achieve this way is limited by the available natural dielectrics, a broad spectrum of features can be realized.

  18. An extension to SUf3 and Dirac particle of the transformation between physical bases and symmetry bases for dibaryon states

    International Nuclear Information System (INIS)

    Ping Jialun

    1994-01-01

    The transformation between physical bases and symmetry bases is extended from SU f 2 to SU f 3 . Its application in dibaryon calculation for both nonrelativistic and relativistic quark model is discussed

  19. Time-temperature-transformation diagram of Zr-based Zr-Al-Cu-Ni metallic glasses

    International Nuclear Information System (INIS)

    Goh, T.T.; Li, Y.; Ng, S.C.

    1996-01-01

    The critical cooling rates R c for glass formation in four Zr-based Zr-Al-Cu-Ni alloys were determined using techniques developed by Uhlmann based on theories of homogeneous nucleation, crystal growth and transformation kinetics. It involves the construction of a time-temperature-transformation curve which requires the knowledge of the viscosity-temperature curve of the alloys. Two types of viscosity-temperature expressions, namely Andrade expression and Doolittle expression, were used to model the viscosity of the Zr-based alloys and the choice of the viscosity-temperature expression which gives the best estimate of the calculated time-temperature-transformation curve is discussed. (author)

  20. Cryo-EM image alignment based on nonuniform fast Fourier transform.

    Science.gov (United States)

    Yang, Zhengfan; Penczek, Pawel A

    2008-08-01

    In single particle analysis, two-dimensional (2-D) alignment is a fundamental step intended to put into register various particle projections of biological macromolecules collected at the electron microscope. The efficiency and quality of three-dimensional (3-D) structure reconstruction largely depends on the computational speed and alignment accuracy of this crucial step. In order to improve the performance of alignment, we introduce a new method that takes advantage of the highly accurate interpolation scheme based on the gridding method, a version of the nonuniform fast Fourier transform, and utilizes a multi-dimensional optimization algorithm for the refinement of the orientation parameters. Using simulated data, we demonstrate that by using less than half of the sample points and taking twice the runtime, our new 2-D alignment method achieves dramatically better alignment accuracy than that based on quadratic interpolation. We also apply our method to image to volume registration, the key step in the single particle EM structure refinement protocol. We find that in this case the accuracy of the method not only surpasses the accuracy of the commonly used real-space implementation, but results are achieved in much shorter time, making gridding-based alignment a perfect candidate for efficient structure determination in single particle analysis.

  1. Cryo-EM image alignment based on nonuniform fast Fourier transform

    International Nuclear Information System (INIS)

    Yang Zhengfan; Penczek, Pawel A.

    2008-01-01

    In single particle analysis, two-dimensional (2-D) alignment is a fundamental step intended to put into register various particle projections of biological macromolecules collected at the electron microscope. The efficiency and quality of three-dimensional (3-D) structure reconstruction largely depends on the computational speed and alignment accuracy of this crucial step. In order to improve the performance of alignment, we introduce a new method that takes advantage of the highly accurate interpolation scheme based on the gridding method, a version of the nonuniform fast Fourier transform, and utilizes a multi-dimensional optimization algorithm for the refinement of the orientation parameters. Using simulated data, we demonstrate that by using less than half of the sample points and taking twice the runtime, our new 2-D alignment method achieves dramatically better alignment accuracy than that based on quadratic interpolation. We also apply our method to image to volume registration, the key step in the single particle EM structure refinement protocol. We find that in this case the accuracy of the method not only surpasses the accuracy of the commonly used real-space implementation, but results are achieved in much shorter time, making gridding-based alignment a perfect candidate for efficient structure determination in single particle analysis

  2. Investigating shape representation using sensitivity to part- and axis-based transformations.

    Science.gov (United States)

    Denisova, Kristina; Feldman, Jacob; Su, Xiaotao; Singh, Manish

    2016-09-01

    Part- and axis-based approaches organize shape representations in terms of simple parts and their spatial relationships. Shape transformations that alter qualitative part structure have been shown to be more detectable than those that preserve it. We compared sensitivity to various transformations that change quantitative properties of parts and their spatial relationships, while preserving qualitative part structure. Shape transformations involving changes in length, width, curvature, orientation and location were applied to a small part attached to a larger base of a two-part shape. Increment thresholds were estimated for each transformation using a 2IFC procedure. Thresholds were converted into common units of shape difference to enable comparisons across transformations. Higher sensitivity was consistently found for transformations involving a parameter of a single part (length, width, curvature) than those involving spatial relations between two parts (relative orientation and location), suggesting a single-part superiority effect. Moreover, sensitivity to shifts in part location - a biomechanically implausible shape transformation - was consistently poorest. The influence of region-based geometry was investigated via stereoscopic manipulation of figure and ground. Sensitivity was compared across positive parts (protrusions) and negative parts (indentations) for transformations involving a change in orientation or location. For changes in part orientation (biomechanically plausible), sensitivity was better for positive than negative parts; whereas for changes in part location (biomechanically implausible), no systematic difference was observed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Electron microscopy study of Nb-rich nanoprecipitates in Ni–Ti–Nb and their influence on the martensitic transformation

    International Nuclear Information System (INIS)

    Shi, H.; Pourbabak, S.; Van Humbeeck, J.; Schryvers, D.

    2012-01-01

    Graphical abstract: -- Nb-rich nanoprecipitates in the matrix of an annealed commercial Ni–Ti–Nb alloy are investigated by scanning and transmission electron microscopy, including slice-and-view and chemical analysis. The precipitates have a diameter of around 100 nm, are faceted and have a cube-on-cube relation with the B2 matrix. In situ TEM cooling shows that the martensitic transformation is hampered by the presence of these precipitates. The latter could explain the increase in hysteresis when compared with the binary system.

  4. Ring-dot-shaped multilayer piezoelectric step-down transformers using PZT-based ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Insung; Joo, Hyeonkyu; Song, Jaesung; Jeong, Soonjong; Kim, Minsoo [Korea Electrotechnology Research Institute, Changwon (Korea, Republic of)

    2010-10-15

    In this study, multilayer piezo stack transformers for switching mode power supply (SMPS) application were manufactured using 0.01Pb(Ni{sub 1/3}Nb{sub 2/3})O{sub 3} - 0.08Pb(Mn{sub 1/3}Nb{sub 2/3})O{sub 3} - 0.91Pb(Zr{sub 0.505}Ti{sub 0.495})O{sub 3} (PNN-PMN-PZT) ceramics. The voltage ratio of a multilayer piezo stack transformer showed a maximum at the resonance frequency of the input and then increased with increasing load resistance. The efficiency of the multilayer piezo stack transformer showed its highest value at around the matching load. The output power increased with increasing input voltage. The temperature of the multilayer piezo stack transformer increased with increasing output power and load resistance. The manufactured multilayer piezo stack transformer could be used up to 5 W at a resonance frequency of 70.25 kHz for SMPS application because the temperature rise from room temperature is believed to about 20 .deg. C and because the transformer is electrically stable. The newly-developed ring-dot-type step-down multilayer piezo stack transformer shows possible applications as SMPS for electronic power sources with excellent input-to-output properties.

  5. Ring-dot-shaped multilayer piezoelectric step-down transformers using PZT-based ceramics

    International Nuclear Information System (INIS)

    Kim, Insung; Joo, Hyeonkyu; Song, Jaesung; Jeong, Soonjong; Kim, Minsoo

    2010-01-01

    In this study, multilayer piezo stack transformers for switching mode power supply (SMPS) application were manufactured using 0.01Pb(Ni 1/3 Nb 2/3 )O 3 - 0.08Pb(Mn 1/3 Nb 2/3 )O 3 - 0.91Pb(Zr 0.505 Ti 0.495 )O 3 (PNN-PMN-PZT) ceramics. The voltage ratio of a multilayer piezo stack transformer showed a maximum at the resonance frequency of the input and then increased with increasing load resistance. The efficiency of the multilayer piezo stack transformer showed its highest value at around the matching load. The output power increased with increasing input voltage. The temperature of the multilayer piezo stack transformer increased with increasing output power and load resistance. The manufactured multilayer piezo stack transformer could be used up to 5 W at a resonance frequency of 70.25 kHz for SMPS application because the temperature rise from room temperature is believed to about 20 .deg. C and because the transformer is electrically stable. The newly-developed ring-dot-type step-down multilayer piezo stack transformer shows possible applications as SMPS for electronic power sources with excellent input-to-output properties.

  6. Electronic structure, excitation properties, and chemical transformations of extreme ultra-violet resist materials

    Science.gov (United States)

    Rangan, Sylvie; Bartynski, Robert A.; Narasimhan, Amrit; Brainard, Robert L.

    2017-07-01

    The electronic structure of extreme ultra violet resist materials and of their individual components, two polymers and two photoacid generators (PAGs), is studied using a combination of x-ray and UV photoemission spectroscopies, electron energy loss spectroscopy, and ab-initio techniques. It is shown that simple molecular models can be used to understand the electronic structure of each sample and describe the experimental data. Additionally, effects directly relevant to the photochemical processes are observed: low energy loss processes are observed for the phenolic polymer containing samples that should favor thermalization of electrons; PAG segregation is measured at the surface of the resist films that could lead to surface inhomogeneities; both PAGs are found to be stable upon irradiation in the absence of the polymer, contrasting with a high reactivity that can be followed upon x-ray irradiation of the full resist.

  7. Missing texture reconstruction method based on error reduction algorithm using Fourier transform magnitude estimation scheme.

    Science.gov (United States)

    Ogawa, Takahiro; Haseyama, Miki

    2013-03-01

    A missing texture reconstruction method based on an error reduction (ER) algorithm, including a novel estimation scheme of Fourier transform magnitudes is presented in this brief. In our method, Fourier transform magnitude is estimated for a target patch including missing areas, and the missing intensities are estimated by retrieving its phase based on the ER algorithm. Specifically, by monitoring errors converged in the ER algorithm, known patches whose Fourier transform magnitudes are similar to that of the target patch are selected from the target image. In the second approach, the Fourier transform magnitude of the target patch is estimated from those of the selected known patches and their corresponding errors. Consequently, by using the ER algorithm, we can estimate both the Fourier transform magnitudes and phases to reconstruct the missing areas.

  8. Terahertz bandwidth all-optical Hilbert transformers based on long-period gratings.

    Science.gov (United States)

    Ashrafi, Reza; Azaña, José

    2012-07-01

    A novel, all-optical design for implementing terahertz (THz) bandwidth real-time Hilbert transformers is proposed and numerically demonstrated. An all-optical Hilbert transformer can be implemented using a uniform-period long-period grating (LPG) with a properly designed amplitude-only grating apodization profile, incorporating a single π-phase shift in the middle of the grating length. The designed LPG-based Hilbert transformers can be practically implemented using either fiber-optic or integrated-waveguide technologies. As a generalization, photonic fractional Hilbert transformers are also designed based on the same optical platform. In this general case, the resulting LPGs have multiple π-phase shifts along the grating length. Our numerical simulations confirm that all-optical Hilbert transformers capable of processing arbitrary optical signals with bandwidths well in the THz range can be implemented using feasible fiber/waveguide LPG designs.

  9. Fast heap transform-based QR-decomposition of real and complex matrices: algorithms and codes

    Science.gov (United States)

    Grigoryan, Artyom M.

    2015-03-01

    In this paper, we describe a new look on the application of Givens rotations to the QR-decomposition problem, which is similar to the method of Householder transformations. We apply the concept of the discrete heap transform, or signal-induced unitary transforms which had been introduced by Grigoryan (2006) and used in signal and image processing. Both cases of real and complex nonsingular matrices are considered and examples of performing QR-decomposition of square matrices are given. The proposed method of QR-decomposition for the complex matrix is novel and differs from the known method of complex Givens rotation and is based on analytical equations for the heap transforms. Many examples illustrated the proposed heap transform method of QR-decomposition are given, algorithms are described in detail, and MATLAB-based codes are included.

  10. Flexible, fpga-based electronics for modular robots

    DEFF Research Database (Denmark)

    Brandt, David; Larsen, Jørgen Christian; Christensen, David Johan

    2008-01-01

    In this paper we introduce electronics for the ATRON self-reconfigurable robot based on field programmable gate arrays (FPGAs). The immediate advantage of using FPGAs is that some of the module’s electronics can be moved into the FPGA, thereby the number of components can be reduced. In the case...... the FPGA and therefore integrate task-specific electronics without physically changing the electronics or we can reconfigure the electronics for specific tasks. The disadvantages of an FPGA-based design include the cost of FPGAs, the extra layer of complexity in programming, and a limited increase in power...... consumption compared to micro-controllers. However, overall FPGAs make the electronics of modular robots more flexible and therefore may make them more suitable for real applications. AB - In this paper we introduce electronics for the ATRON self-reconfigurable robot based on field programmable gate arrays...

  11. Electronic patient records in action: Transforming information into professionally relevant knowledge.

    Science.gov (United States)

    Winman, Thomas; Rystedt, Hans

    2011-03-01

    The implementation of generic models for organizing information in complex institutions like those in healthcare creates a gap between standardization and the need for locally relevant knowledge. The present study addresses how this gap can be bridged by focusing on the practical work of healthcare staff in transforming information in EPRs into knowledge that is useful for everyday work. Video recording of shift handovers on a rehabilitation ward serves as the empirical case. The results show how extensive selections and reorganizations of information in EPRs are carried out in order to transform information into professionally relevant accounts. We argue that knowledge about the institutional obligations and professional ways of construing information are fundamental for these transitions. The findings point to the need to consider the role of professional knowledge inherent in unpacking information in efforts to develop information systems intended to bridge between institutional and professional boundaries in healthcare. © The Author(s) 2011.

  12. Transformation of chinese retail industry: how to meet the new challenges by electronic business?

    OpenAIRE

    Liu, Xinyang; Li, Kai

    2015-01-01

    The past few decades witnessed the rise and expansion of electronic business (EB). An increasing number of companies are dealing with electronic commerce many of whom are well-known nationwide or worldwide leaders such as the Alibaba Group or JD.COM. On one day, 11th of November of 2014, the trading volume of Taobao reached 6 million RMB. The unprecedented development of EB has threatened traditional retail firms. Manufacturers as well as retailers need to reconsider their methods and make...

  13. SECURE VISUAL SECRET SHARING BASED ON DISCRETE WAVELET TRANSFORM

    Directory of Open Access Journals (Sweden)

    S. Jyothi Lekshmi

    2015-08-01

    Full Text Available Visual Cryptography Scheme (VCS is an encryption method to encode secret written materials. This method converts the secret written material into an image. Then encode this secret image into n shadow images called shares. For the recreation of the original secret, all or some selected subsets of shares are needed; individual shares are of no use on their own. The secret image can be recovered simply by selecting some subset of these n shares, makes transparencies of them and stacking on top of each other. Nowadays, the data security has an important role. The shares can be altered by an attacker. So providing security to the shares is important. This paper proposes a method of adding security to cryptographic shares. This method uses two dimensional discrete wavelet transform to hide visual secret shares. Then the hidden secrets are distributed among participants through the internet. All hidden shares are extracted to reconstruct the secret.

  14. Modal Analysis Based on the Random Decrement Transform

    DEFF Research Database (Denmark)

    Asmussen, J. C.; Brincker, Rune; Ibrahim, S. R.

    of this paper is to present a state-of-the-art description of the Random Decrement technique where the statistical theory is outlined and examples are given. But also new results such as estimation of frequency response functions and quality assessment are introduced. Special attention is given......During the last years several papers utilizing the Random Decrement transform as a basis for extraction of modal parameters from the response of linear systems subjected to unknown ambient loads have been presented. Although the Random Decrement technique was developed in a decade starting from...... the introduktion in 1968 the technique seems still to be attractive. This is probably due to the simplicity and the speed of the algorithm and the fact that the theory of the technique has been extended by introducing statistical measures such as correlation functions or spectral densities. The purpose...

  15. E-government and the Electronic Transformation of Modes of Rule: The Case of Partnerships

    Directory of Open Access Journals (Sweden)

    Paul Henman

    2004-04-01

    Full Text Available This paper critically examines some aspects of the discursive and material transformation of government as a result the deployment of the internet and new information technologies. Particular attention is given to the constitution of partnerships and network forms of governing. The paper illustrates the dynamics of egovernment through two case studies of e-government projects in Australia's social security/welfare system.

  16. Analytical electron microscope study of the omega phase transformation in a zirconium-niobium alloy

    International Nuclear Information System (INIS)

    Zaluzec, N.J.

    1979-01-01

    The study of the as-quenched omega phase morphology shows that the domain size of Zr-15% Nb is on the order of 30 A. No alignment of omega domains along β directions was observed and samples having undergone thermal cycling in thin foil form, did not develop a long-period structure of alternating β and ω phases below the omega transformation temperature

  17. 3D seismic denoising based on a low-redundancy curvelet transform

    International Nuclear Information System (INIS)

    Cao, Jingjie; Zhao, Jingtao; Hu, Zhiying

    2015-01-01

    Contamination of seismic signal with noise is one of the main challenges during seismic data processing. Several methods exist for eliminating different types of noises, but optimal random noise attenuation remains difficult. Based on multi-scale, multi-directional locality of curvelet transform, the curvelet thresholding method is a relatively new method for random noise elimination. However, the high redundancy of a 3D curvelet transform makes its computational time and memory for massive data processing costly. To improve the efficiency of the curvelet thresholding denoising, a low-redundancy curvelet transform was introduced. The redundancy of the low-redundancy curvelet transform is approximately one-quarter of the original transform and the tightness of the original transform is also kept, thus the low-redundancy curvelet transform calls for less memory and computational resource compared with the original one. Numerical results on 3D synthetic and field data demonstrate that the low-redundancy curvelet denoising consumes one-quarter of the CPU time compared with the original curvelet transform using iterative thresholding denoising when comparable results are obtained. Thus, the low-redundancy curvelet transform is a good candidate for massive seismic denoising. (paper)

  18. Chaos-based partial image encryption scheme based on linear fractional and lifting wavelet transforms

    Science.gov (United States)

    Belazi, Akram; Abd El-Latif, Ahmed A.; Diaconu, Adrian-Viorel; Rhouma, Rhouma; Belghith, Safya

    2017-01-01

    In this paper, a new chaos-based partial image encryption scheme based on Substitution-boxes (S-box) constructed by chaotic system and Linear Fractional Transform (LFT) is proposed. It encrypts only the requisite parts of the sensitive information in Lifting-Wavelet Transform (LWT) frequency domain based on hybrid of chaotic maps and a new S-box. In the proposed encryption scheme, the characteristics of confusion and diffusion are accomplished in three phases: block permutation, substitution, and diffusion. Then, we used dynamic keys instead of fixed keys used in other approaches, to control the encryption process and make any attack impossible. The new S-box was constructed by mixing of chaotic map and LFT to insure the high confidentiality in the inner encryption of the proposed approach. In addition, the hybrid compound of S-box and chaotic systems strengthened the whole encryption performance and enlarged the key space required to resist the brute force attacks. Extensive experiments were conducted to evaluate the security and efficiency of the proposed approach. In comparison with previous schemes, the proposed cryptosystem scheme showed high performances and great potential for prominent prevalence in cryptographic applications.

  19. HAAR TRANSFORM BASED ESTIMATION OF CHLOROPHYLL AND STRUCTURE OF THE LEAF

    OpenAIRE

    Abhinav Arora; R. Menaka; Shivangi Gupta; Archit Mishra

    2013-01-01

    In this paper, the health of a plant is estimated using various non-destructive Image Processing Techniques. Chlorophyll content was detected based on colour Image Processing. The Haar transform is applied to get size of leaf and the parameters.

  20. Quaternion-based transformation for extraction of image-generating Doppler for ISAR

    CSIR Research Space (South Africa)

    Abdul Gaffar, MY

    2008-10-01

    Full Text Available contributing motion that is useful to the ISAR imaging process; the contributing motion consists of the Doppler generating axis and the effective angle of rotation. This letter presents a quaternion-based transformation that converts measured attitude...

  1. Detecting Structural Metadata with Decision Trees and Transformation-Based Learning

    National Research Council Canada - National Science Library

    Kim, Joungbum; Schwarm, Sarah E; Ostendorf, Mari

    2004-01-01

    .... Specifically, combinations of decision trees and language models are used to predict sentence ends and interruption points and given these events transformation based learning is used to detect edit...

  2. Sunlight-induced Transformations of Graphene-based Nanomaterials in Aquatic Environments

    Science.gov (United States)

    Graphene-based nanomaterials and other related carbon nanomaterials (CNMs) can be released from products during their life cycles. Upon entry into aquatic environments, they are potentially transformed by photochemical reactions, oxidation reactions and biological processes, all ...

  3. Structural transformations in thermal treatment of carbon material based on Slantsy coke

    Energy Technology Data Exchange (ETDEWEB)

    Tyumentsev, V.A.; Semenov, P.V.; Podkopaev, S.A.; Noneshneva, N.P.; Golovin, A.V. [Chelyabinsk State University, Chelyabinsk (Russian Federation)

    2000-07-01

    Structural transformations occurring in a carbon material based on high-sulfur Slantsy coke during isothermal treatment (1200-2400{degree}C) under normal pressure in a nitrogen atmosphere were studied.

  4. Pseudogap in the Eliashberg approach based on electron-phonon and electron-electron-phonon interaction

    Energy Technology Data Exchange (ETDEWEB)

    Szczesniak, R. [Institute of Physics, Czestochowa University of Technology (Poland); Institute of Physics, Jan Dlugosz University in Czestochowa (Poland); Durajski, A.P.; Duda, A.M. [Institute of Physics, Czestochowa University of Technology (Poland)

    2017-04-15

    The properties of the superconducting and the anomalous normal state were described by using the Eliashberg method. The pairing mechanism was reproduced with the help of the Hamiltonian, which models the electron-phonon and the electron-electron-phonon interaction (EEPh). The set of the Eliashberg equations, which determines the order parameter function (φ), the wave function renormalization factor (Z), and the energy shift function (χ), was derived. It was proven that for the sufficiently large values of the EEPh potential, the doping dependence of the order parameter (φ/Z) has the analogous course to that observed experimentally in cuprates. The energy gap in the electron density of states is induced by Z and χ - the contribution from φ is negligible. The electron density of states possesses the characteristic asymmetric form and the pseudogap is observed above the critical temperature. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Power Transformer Differential Protection Based on Neural Network Principal Component Analysis, Harmonic Restraint and Park's Plots

    OpenAIRE

    Tripathy, Manoj

    2012-01-01

    This paper describes a new approach for power transformer differential protection which is based on the wave-shape recognition technique. An algorithm based on neural network principal component analysis (NNPCA) with back-propagation learning is proposed for digital differential protection of power transformer. The principal component analysis is used to preprocess the data from power system in order to eliminate redundant information and enhance hidden pattern of differential current to disc...

  6. Developing a model for application of electronic banking based on electronic trust

    Directory of Open Access Journals (Sweden)

    Amir Hooshang Nazarpoori

    2014-05-01

    Full Text Available This study develops a model for application of electronic banking based on electronic trust among costumers of Day bank in KhoramAbad city. A sample of 150 people was selected based on stratified random sampling. Questionnaires were used for the investigation. Results indicate that technology-based factors, user-based factors, and trust had negative relationships with perceived risk types including financial, functional, personal, and private. Moreover, trust including trust in system and trust in bank had a positive relationship with tendency to use and real application of electronic banking.

  7. Loss of cellular transformation efficiency induced by DNA irradiation with low-energy (10 eV) electrons.

    Science.gov (United States)

    Kouass Sahbani, Saloua; Sanche, Leon; Cloutier, Pierre; Bass, Andrew D; Hunting, Darel J

    2014-11-20

    Low energy electrons (LEEs) of energies less than 20 eV are generated in large quantities by ionizing radiation in biological matter. While LEEs are known to induce single (SSBs) and double strand breaks (DSBs) in DNA, their ability to inactivate cells by inducing nonreparable lethal damage has not yet been demonstrated. Here we observe the effect of LEEs on the functionality of DNA, by measuring the efficiency of transforming Escherichia coli with a [pGEM-3Zf (-)] plasmid irradiated with 10 eV electrons. Highly ordered DNA films were prepared on pyrolitic graphite by molecular self-assembly using 1,3-diaminopropane ions (Dap(2+)). The uniformity of these films permits the inactivation of approximately 50% of the plasmids compared to transforming cluster damage into DSBs by digestion with repair enzymes, also occurred relatively infrequently. The exact nature of the lethal damage remains unknown, but it is probably a form of compact cluster damage in which the lesions are too close to be revealed by purified repair enzymes. In addition, this damage is either not repaired or is misrepaired by E. coli, since it results in plasmid inactivation, when they contain an average of three lesions. Comparison with previous results from a similar experiment performed with γ-irradiated plasmids indicates that the type of clustered DNA lesions, created directly on cellular DNA by LEEs, may be more difficult to repair than those produced by other species from radiolysis.

  8. A low-noise measurement system for scanning thermal microscopy resistive nanoprobes based on a transformer ratio-arm bridge

    Science.gov (United States)

    Świątkowski, Michał; Wojtuś, Arkadiusz; Wielgoszewski, Grzegorz; Rudek, Maciej; Piasecki, Tomasz; Jóźwiak, Grzegorz; Gotszalk, Teodor

    2018-04-01

    Atomic force microscopy (AFM) is a widely used technology for the investigation and characterization of nanomaterials. Its functionality can be easily expanded by applying dedicated extension modules, which can measure the electrical conductivity or temperature of a sample. In this paper, we introduce a transformer ratio-arm bridge setup dedicated to AFM-based thermal imaging. One of the key features of the thermal module is the use of a low-power driving signal that prevents undesirable tip heating during resistance measurement, while the other is the sensor location in a ratio-arm transformer bridge working in the audio frequency range and ensuring galvanic isolation of the tip, enabling contact-mode scanning of electronic circuits. The proposed expansion module is compact and it can be integrated onto the AFM head close to the cantilever. The calibration process and the resolution of 11 mK of the proposed setup are shown.

  9. Validation of a numerical algorithm based on transformed equations

    International Nuclear Information System (INIS)

    Xu, H.; Barron, R.M.; Zhang, C.

    2003-01-01

    Generally, a typical equation governing a physical process, such as fluid flow or heat transfer, has three types of terms that involve partial derivatives, namely, the transient term, the convective terms and the diffusion terms. The major difficulty in obtaining numerical solutions of these partial differential equations is the discretization of the convective terms. The transient term is usually discretized using the first-order forward or backward differencing scheme. The diffusion terms are usually discretized using the central differencing scheme and no difficulty arises since these terms involve second-order spatial derivatives of the flow variables. The convective terms are non-linear and contain first-order spatial derivatives. The main difference between various numerical algorithms is the discretization of the convective terms. In the present study, an alternative approach to discretizing the governing equations is presented. In this algorithm, the governing equations are first transformed by introducing an exponential function to eliminate the convective terms in the equations. The proposed algorithm is applied to simulate some fluid flows with exact solutions to validate the proposed algorithm. The fluid flows used in this study are a self-designed quasi-fluid flow problem, stagnation in plane flow (Hiemenz flow), and flow between two concentric cylinders. The comparisons with the power-law scheme indicate that the proposed scheme exhibits better performance. (author)

  10. Can big data transform electronic health records into learning health systems?

    Science.gov (United States)

    Harper, Ellen

    2014-01-01

    In the United States and globally, healthcare delivery is in the midst of an acute transformation with the adoption and use of health information technology (health IT) thus generating increasing amounts of patient care data available in computable form. Secure and trusted use of these data, beyond their original purpose can change the way we think about business, health, education, and innovation in the years to come. "Big Data" is data whose scale, diversity, and complexity require new architecture, techniques, algorithms, and analytics to manage it and extract value and hidden knowledge from it.

  11. Single electron based binary multipliers with overflow detection ...

    African Journals Online (AJOL)

    electron based device. Multipliers with overflow detection based on serial and parallel prefix computation algorithm are elaborately discussed analytically and designed. The overflow detection circuits works in parallel with a simplified multiplier to ...

  12. A Power Transformers Fault Diagnosis Model Based on Three DGA Ratios and PSO Optimization SVM

    Science.gov (United States)

    Ma, Hongzhe; Zhang, Wei; Wu, Rongrong; Yang, Chunyan

    2018-03-01

    In order to make up for the shortcomings of existing transformer fault diagnosis methods in dissolved gas-in-oil analysis (DGA) feature selection and parameter optimization, a transformer fault diagnosis model based on the three DGA ratios and particle swarm optimization (PSO) optimize support vector machine (SVM) is proposed. Using transforming support vector machine to the nonlinear and multi-classification SVM, establishing the particle swarm optimization to optimize the SVM multi classification model, and conducting transformer fault diagnosis combined with the cross validation principle. The fault diagnosis results show that the average accuracy of test method is better than the standard support vector machine and genetic algorithm support vector machine, and the proposed method can effectively improve the accuracy of transformer fault diagnosis is proved.

  13. Analysis for pressure transient of coalbed methane reservoir based on Laplace transform finite difference method

    Directory of Open Access Journals (Sweden)

    Lei Wang

    2015-09-01

    Full Text Available Based on fractal geometry, fractal medium of coalbed methane mathematical model is established by Langmuir isotherm adsorption formula, Fick's diffusion law, Laplace transform formula, considering the well bore storage effect and skin effect. The Laplace transform finite difference method is used to solve the mathematical model. With Stehfest numerical inversion, the distribution of dimensionless well bore flowing pressure and its derivative was obtained in real space. According to compare with the results from the analytical method, the result from Laplace transform finite difference method turns out to be accurate. The influence factors are analyzed, including fractal dimension, fractal index, skin factor, well bore storage coefficient, energy storage ratio, interporosity flow coefficient and the adsorption factor. The calculating error of Laplace transform difference method is small. Laplace transform difference method has advantages in well-test application since any moment simulation does not rely on other moment results and space grid.

  14. An informatics approach to transformation temperatures of NiTi-based shape memory alloys

    International Nuclear Information System (INIS)

    Xue, Dezhen; Xue, Deqing; Yuan, Ruihao; Zhou, Yumei; Balachandran, Prasanna V.; Ding, Xiangdong; Sun, Jun; Lookman, Turab

    2017-01-01

    The martensitic transformation serves as the basis for applications of shape memory alloys (SMAs). The ability to make rapid and accurate predictions of the transformation temperature of SMAs is therefore of much practical importance. In this study, we demonstrate that a statistical learning approach using three features or material descriptors related to the chemical bonding and atomic radii of the elements in the alloys, provides a means to predict transformation temperatures. Together with an adaptive design framework, we show that iteratively learning and improving the statistical model can accelerate the search for SMAs with targeted transformation temperatures. The possible mechanisms underlying the dependence of the transformation temperature on these features is discussed based on a Landau-type phenomenological model.

  15. Graphene-based polymer nanocomposites in electronics

    CERN Document Server

    Sadasivuni, Kishor Kumar; Kim, Jaehwan

    2015-01-01

    This book covers graphene reinforced polymers, which are useful in electronic applications, including electrically conductive thermoplastics composites, thermosets and elastomers. It systematically introduces the reader to fundamental aspects and leads over to actual applications, such as sensor fabrication, electromagnetic interference shielding, optoelectronics, superconductivity, or memory chips. The book also describes dielectric and thermal behaviour of graphene polymer composites - properties which are essential to consider for the fabrication and production of these new electronic materials. The contributions in this book critically discuss the actual questions in the development and applications of graphene polymer composites. It will thus appeal to chemists, physicists, materials scientists as well as nano technologists, who are interested in the properties of graphene polymer composites.

  16. In-situ studies on phase transformations under electron irradiation in ...

    Indian Academy of Sciences (India)

    M. Senthilkumar (Newgen Imaging) 1461 1996 Oct 15 13:05:22

    under 1 MeV electron irradiation at 300 K has been recorded in HVEM experiments. The similarity of the diffuse intensity distribution in these two cases brings out the importance of the lattice collapse mechanism in both the cases. 2. Crystallography of the ordered phases in Ni–Mo system. The equilibrium phase diagram of ...

  17. A molecular shift register based on electron transfer

    Science.gov (United States)

    Hopfield, J. J.; Onuchic, Josenelson; Beratan, David N.

    1988-01-01

    An electronic shift-register memory at the molecular level is described. The memory elements are based on a chain of electron-transfer molecules and the information is shifted by photoinduced electron-transfer reactions. This device integrates designed electronic molecules onto a very large scale integrated (silicon microelectronic) substrate, providing an example of a 'molecular electronic device' that could actually be made. The design requirements for such a device and possible synthetic strategies are discussed. Devices along these lines should have lower energy usage and enhanced storage density.

  18. Compressive sensing based algorithms for electronic defence

    CERN Document Server

    Mishra, Amit Kumar

    2017-01-01

    This book details some of the major developments in the implementation of compressive sensing in radio applications for electronic defense and warfare communication use. It provides a comprehensive background to the subject and at the same time describes some novel algorithms. It also investigates application value and performance-related parameters of compressive sensing in scenarios such as direction finding, spectrum monitoring, detection, and classification.

  19. Stretchable and foldable silicon-based electronics

    KAUST Repository

    Cavazos Sepulveda, Adrian Cesar

    2017-03-30

    Flexible and stretchable semiconducting substrates provide the foundation for novel electronic applications. Usually, ultra-thin, flexible but often fragile substrates are used in such applications. Here, we describe flexible, stretchable, and foldable 500-μm-thick bulk mono-crystalline silicon (100) “islands” that are interconnected via extremely compliant 30-μm-thick connectors made of silicon. The thick mono-crystalline segments create a stand-alone silicon array that is capable of bending to a radius of 130 μm. The bending radius of the array does not depend on the overall substrate thickness because the ultra-flexible silicon connectors are patterned. We use fracture propagation to release the islands. Because they allow for three-dimensional monolithic stacking of integrated circuits or other electronics without any through-silicon vias, our mono-crystalline islands can be used as a “more-than-Moore” strategy and to develop wearable electronics that are sufficiently robust to be compatible with flip-chip bonding.

  20. Electronic neutron sensor based on coincidence detection

    International Nuclear Information System (INIS)

    Barelaud, B.; Decossas, J.L.; Mokhtari, F.; Vareille, J.C.

    1996-01-01

    The last symposium on neutron dosimetry which took place in Paris in November 1995 have shown again that it doesn't exist any individual active neutron dosemeter. The state of art on electronic device, the needs of the nuclear power industry in individual neutron monitoring and the new trends of The last symposium on neutron dosimetry which took place in Paris in November 1995 have shown again that it doesn't exist any individual active neutron dosemeter. The state of art on electronic device, the needs of the nuclear power industry in individual neutron monitoring and the new trends of researches were presented. They confirm the relevance of our studies in progress in the C2M team of the University of Limoges. The aim of this work is to realize an individual electronic neutron dosemeter. The device in the progress of being development will operate either as a dosemeter or as ratemeter giving H p (10) and H p (10) either as a spectrometer permitting to characterize the primary neutron beam. (author)

  1. Stretchable and foldable silicon-based electronics

    KAUST Repository

    Cavazos Sepulveda, Adrian Cesar; Diaz Cordero, M. S.; Carreno, Armando Arpys Arevalo; Nassar, Joanna M.; Hussain, Muhammad Mustafa

    2017-01-01

    Flexible and stretchable semiconducting substrates provide the foundation for novel electronic applications. Usually, ultra-thin, flexible but often fragile substrates are used in such applications. Here, we describe flexible, stretchable, and foldable 500-μm-thick bulk mono-crystalline silicon (100) “islands” that are interconnected via extremely compliant 30-μm-thick connectors made of silicon. The thick mono-crystalline segments create a stand-alone silicon array that is capable of bending to a radius of 130 μm. The bending radius of the array does not depend on the overall substrate thickness because the ultra-flexible silicon connectors are patterned. We use fracture propagation to release the islands. Because they allow for three-dimensional monolithic stacking of integrated circuits or other electronics without any through-silicon vias, our mono-crystalline islands can be used as a “more-than-Moore” strategy and to develop wearable electronics that are sufficiently robust to be compatible with flip-chip bonding.

  2. Transforming bases to bytes: Molecular computing with DNA

    Indian Academy of Sciences (India)

    Despite the popular image of silicon-based computers for computation, an embryonic field of mole- cular computation is emerging, where molecules in solution perform computational ..... [4] Mao C, Sun W, Shen Z and Seeman N C 1999. A nanomechanical device based on the B-Z transition of DNA; Nature 397 144–146.

  3. Analysis of Satellite Drag Coefficient Based on Wavelet Transform

    Science.gov (United States)

    Liu, Wei; Wang, Ronglan; Liu, Siqing

    Abstract: Drag coefficient sequence was obtained by solving Tiangong1 continuous 55days GPS orbit data with different arc length. The same period solar flux f10.7 and geomagnetic index Ap ap series were high and low frequency multi-wavelet decomposition. Statistical analysis results of the layers sliding correlation between space environmental parameters and decomposition of Cd, showed that the satellite drag coefficient sequence after wavelet decomposition and the corresponding level of f10.7 Ap sequence with good lag correlation. It also verified that the Cd prediction is feasible. Prediction residuals of Cd with different regression models and different sample length were analysed. The results showed that the case was best when setting sample length 20 days and f10.7 regression model were used. It also showed that NRLMSIS-00 model's response in the region of 350km (Tiangong's altitude) and low-middle latitude (Tiangong's inclination) is excessive in ascent stage of geomagnetic activity Ap and is inadequate during fall off segment. Additionally, the low-frequency decomposition components NRLMSIS-00 model's response is appropriate in f10.7 rising segment. High frequency decomposition section, Showed NRLMSIS-00 model's response is small-scale inadequate during f10.7 ascent segment and is reverse in decline of f10.7. Finally, the potential use of a summary and outlook were listed; This method has an important reference value to improve the spacecraft orbit prediction accuracy. Key words: wavelet transform; drag coefficient; lag correlation; Tiangong1;space environment

  4. Effect of electron irradiation and heat treatment on the multi-step transformation in a Ni-rich near-equiatomic TiNi alloy

    International Nuclear Information System (INIS)

    Wang, Z.G.; Zu, X.T.; Huo, Y.; Zhu, S.; Wei, X.W.; Wang, L.M.

    2004-01-01

    In this work, Ti-50.6 at.% Ni shape memory alloy were solution annealed at 800 deg. C for 20 min and quenched in icy water, further annealing were done at 380 deg. C for 1 h, and then irradiated with 1.7 MeV electron at the fluence of 3.2 x 10 20 -12.8 x 10 20 m -2 . The evolution of transformation temperatures was studied by differential scanning calorimeter (DSC). Effect of annealing on the evolution of multiple-step transformation temperatures also investigated. Heat treatment and irradiation had a prominent effect on the transformation, but with different characteristics. The M 1 (the first R-phase → martensite transformation) showed little change after irradiation, but the M 2 (the second R-phase → martensite transformation) transformation temperature decreased with increasing electron fluence and disappeared at the fluence of 12.8 x 10 20 m -2 . Heat treatment causes the shift of R-phase transformation start/finish temperature (R s /R f ) to lower temperature and the shift of M 1 and M 2 transformation temperatures to higher temperature. The peaks of M 1 and M 2 almost merged into one peak with increasing annealing temperature. The effects of irradiation and annealing on the transformation characteristics are not exchangeable, so irradiation is also an important method for the study of condensed matter

  5. Neural network based electron identification in the ZEUS calorimeter

    International Nuclear Information System (INIS)

    Abramowicz, H.; Caldwell, A.; Sinkus, R.

    1995-01-01

    We present an electron identification algorithm based on a neural network approach applied to the ZEUS uranium calorimeter. The study is motivated by the need to select deep inelastic, neutral current, electron proton interactions characterized by the presence of a scattered electron in the final state. The performance of the algorithm is compared to an electron identification method based on a classical probabilistic approach. By means of a principle component analysis the improvement in the performance is traced back to the number of variables used in the neural network approach. (orig.)

  6. Wavelet packet transform-based robust video watermarking technique

    Indian Academy of Sciences (India)

    If any conflict happens to the copyright identification and authentication, ... the present work is concentrated on the robust digital video watermarking. .... the wavelet decomposition, resulting in a new family of orthonormal bases for function ...

  7. Sea Basing: Evolutionary Naval Doctrine and Military Transformation

    National Research Council Canada - National Science Library

    Gentry, Robin

    2004-01-01

    .... Sea Basing through a combination of naval platforms provides the bridge for the American military forces between the advance force operations needed to prepare the battlespace and the war-winning...

  8. Atomic and electronic structure transformations of silver nanoparticles under rapid cooling conditions

    OpenAIRE

    Lobato, I.; Rojas, J.; Landauro, C. V.; Torres, J.

    2008-01-01

    The structural evolution and dynamics of silver nanodrops Ag${}_{2896}$ (4.4 nm in diameter) during rapid cooling conditions has been studied by means of molecular dynamics simulations and electronic density of state calculations. The interaction of silver atoms is modeled by a tight-binding semiempirical interatomic potential proposed by Cleri and Rosato. The pair correlation functions and the pair analysis technique is applied to reveal the structural transition in the process of solidifica...

  9. Voltage surges induced in transformer secondaries with loads characterized by sensitive electronic equipment

    Energy Technology Data Exchange (ETDEWEB)

    Cogo, Joao Roberto [GSI Engenharia e Consultoria Ltda., Taubate, SP (Brazil)], Email: gsi@gsiconsultoria.com.br; Dommel, Hermann Wilhelm [University of British Columbia, Vancouver (Canada)], Email: hermannd@ece.ubc.ca

    2007-07-01

    The grounding of sensitive electronic equipment such as computers, programmable logic controllers (PLC), process control systems, and other electronic equipment is one of the most important considerations towards obtaining an efficient operation of such systems. Such equipment, which for the purposes of this work is called 'Sensitive Electronic Equipment - SEE' is very sensitive to faults and low intensity random voltages which have no effect upon the electrical power equipment and upon human beings. In this work, the grounding problem is evaluated, to guide the user on the proper installation of SEEs, so as to prevent them from being damaged. The following items will be discussed: voltages which SEEs are subject to during incidence of atmospheric surges in the distribution overhead lines to which they are connected; sustained voltage that the high voltage supply of SEEs must be able to withstand during line-to-ground faults that originate from atmospheric surges that reach the transmission lines which are connected to the electrical power self producers (or electrical power independent producers). (author)

  10. Selecting a summation base in diffraction transformation of seismic recordings (in an example of Northern Sakhalin)

    Energy Technology Data Exchange (ETDEWEB)

    Bulatov, M.G.; Telegin, A.N.

    1984-01-01

    The effect of the dimensions of a processing base on the results of diffraction transformation of seismic recordings is examined. A formula is cited for rating the optimal summation base on the basis of a proposed range of slant angles of the reflecting boundaries. The recommendations for selecting a processing base are confirmed by factual material.

  11. Building Modern Vibration Diagnostics Systems Based on the Frequency-Time Transformations of A Measured Signal

    Directory of Open Access Journals (Sweden)

    Yasoveev Vasikh

    2016-01-01

    Full Text Available Basic methods of analysis of vibration transducers signals were reviewed. Continuous wavelet transform, being a time-frequency transform, was found to be an advanced mathematical tool for analysis of vibration signals. Experimental studies revealed obvious changes in the continuous wavelet transform spectrum depending on the existing defects. A method for detection and identification of technological violations based on the analysis of CWT spectrum components and normalized correlation coefficient was suggested. In accordance with the suggested method software for vibration diagnostics was developed.

  12. Room-Temperature Deformation and Martensitic Transformation of Two Co-Cr-Based Alloys

    Science.gov (United States)

    Cai, S.; Schaffer, J. E.; Huang, D.; Gao, J.; Ren, Y.

    2018-05-01

    Deformation of two Co-Cr alloys was studied by in situ synchrotron X-ray diffraction. Both alloys show stress-induced martensite transformation, which is affected by phase stabilities and transformation strains. Crystal structure of WC in Co-20Cr-15W-10Ni is identified. Compared with other phases present, it is elastically isotropic, exhibits high strength, and can elastically withstand strains exceeding 1 pct. Texture change during phase transformation is explained based on the crystal orientation relationship between γ- and ɛ-phases.

  13. Transformations to diagonal bases in closed-loop quantum learning control experiments

    International Nuclear Information System (INIS)

    Cardoza, David; Trallero-Herrero, Carlos; Langhojer, Florian; Rabitz, Herschel; Weinacht, Thomas

    2005-01-01

    This paper discusses transformations between bases used in closed-loop learning control experiments. The goal is to transform to a basis in which the number of control parameters is minimized and in which the parameters act independently. We demonstrate a simple procedure for testing whether a unitary linear transformation (i.e., a rotation amongst the control variables) is sufficient to reduce the search problem to a set of globally independent variables. This concept is demonstrated with closed-loop molecular fragmentation experiments utilizing shaped, ultrafast laser pulses

  14. Electron energy and electron trajectories in an inverse free-electron laser accelerator based on a novel electrostatic wiggler

    Science.gov (United States)

    Nikrah, M.; Jafari, S.

    2016-06-01

    We expand here a theory of a high-gradient laser-excited electron accelerator based on an inverse free-electron laser (inverse-FEL), but with innovations in the structure and design. The electrostatic wiggler used in our scheme, namely termed the Paul wiggler, is generated by segmented cylindrical electrodes with applied oscillatory voltages {{V}\\text{osc}}(t) over {{90}\\circ} segments. The inverse-FEL interaction can be described by the equations that govern the electron motion in the combined fields of both the laser pulse and Paul wiggler field. A numerical study of electron energy and electron trajectories has been made using the fourth-order Runge-Kutta method. The results indicate that the electron attains a considerable energy at short distances in this device. It is found that if the electron has got sufficient suitable wiggler amplitude intensities, it can not only gain higher energy in longer distances, but also can retain it even after the passing of the laser pulse. In addition, the results reveal that the electron energy gains different peaks for different initial axial velocities, so that a suitable small initial axial velocity of e-beam produces substantially high energy gain. With regard to the transverse confinement of the electron beam in a Paul wiggler, there is no applied axial guide magnetic field in this device.

  15. A novel algorithm for discrimination between inrush current and internal faults in power transformer differential protection based on discrete wavelet transform

    Energy Technology Data Exchange (ETDEWEB)

    Eldin, A.A. Hossam; Refaey, M.A. [Electrical Engineering Department, Alexandria University, Alexandria (Egypt)

    2011-01-15

    This paper proposes a novel methodology for transformer differential protection, based on wave shape recognition of the discriminating criterion extracted of the instantaneous differential currents. Discrete wavelet transform has been applied to the differential currents due to internal fault and inrush currents. The diagnosis criterion is based on median absolute deviation (MAD) of wavelet coefficients over a specified frequency band. The proposed algorithm is examined using various simulated inrush and internal fault current cases on a power transformer that has been modeled using electromagnetic transients program EMTDC software. Results of evaluation study show that, proposed wavelet based differential protection scheme can discriminate internal faults from inrush currents. (author)

  16. Phase difference estimation method based on data extension and Hilbert transform

    International Nuclear Information System (INIS)

    Shen, Yan-lin; Tu, Ya-qing; Chen, Lin-jun; Shen, Ting-ao

    2015-01-01

    To improve the precision and anti-interference performance of phase difference estimation for non-integer periods of sampling signals, a phase difference estimation method based on data extension and Hilbert transform is proposed. Estimated phase difference is obtained by means of data extension, Hilbert transform, cross-correlation, auto-correlation, and weighted phase average. Theoretical analysis shows that the proposed method suppresses the end effects of Hilbert transform effectively. The results of simulations and field experiments demonstrate that the proposed method improves the anti-interference performance of phase difference estimation and has better performance of phase difference estimation than the correlation, Hilbert transform, and data extension-based correlation methods, which contribute to improving the measurement precision of the Coriolis mass flowmeter. (paper)

  17. Local structure and phase transformation in Zr and Ti based bcc solutions

    International Nuclear Information System (INIS)

    Chang, A.L.J.

    1975-01-01

    High resolution direct lattice imaging and dark field electron microscopy were used to examine the omega phase transformation in Zr--Nb alloys. Direct lattice imaging demonstrates the existence of three subvariants within each omega variant. The kinematic intensity sum, which is evaluated based on the combination of certain atomic arrangements, was carried out to include both untransformed beta phase and the omega phase. An ordered sequence of subvariants was found to be responsible for the diffraction effects in high Nb content alloys. However, the existence of such an ordered sequence among omega subvariants could not be checked out because of the small size of the omega regions. Omega domains of different variant do not interweave. Isolated particles with diameters of 3 to 5 A also are present away from the domains. As the Nb content is increased the omega domains decrease in size while the isolated particles (3 to 5 A) are present over the entire range studied, from 8 to 30 wt percent Nb. It is suggested that fluctuations in structure occur between the beta and omega phases. The isolated particles, also changing with time, are believed to be images of single or small groups of displaced atoms. (Diss. Abstr. Int., B)

  18. CRISPR-Based Antibacterials: Transforming Bacterial Defense into Offense.

    Science.gov (United States)

    Greene, Adrienne C

    2018-02-01

    The development of antimicrobial-resistant (AMR) bacteria poses a serious worldwide health concern. CRISPR-based antibacterials are a novel and adaptable method for building an arsenal of antibacterials potentially capable of targeting any pathogenic bacteria. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Nonlinear Effects in Transformation Optics-Based Metamaterial Shields for Counter Directed Energy Weapon Defense

    Science.gov (United States)

    2016-06-01

    employs the in- variance of the Maxwell equations under coordinate transformations to convert the free- space wave solutions in a coordinate... ENERGY WEAPON DEFENSE by Jacob D. Thompson June 2016 Thesis Co-Advisors: James Luscombe Brett Borden Approved for public release; distribution is...2014 to 06-17-2016 4. TITLE AND SUBTITLE NONLINEAR EFFECTS IN TRANSFORMATION OPTICS-BASED METAMATE- RIAL SHIELDS FOR COUNTER DIRECTED ENERGY WEAPON

  20. Multi-stage phase retrieval algorithm based upon the gyrator transform.

    Science.gov (United States)

    Rodrigo, José A; Duadi, Hamootal; Alieva, Tatiana; Zalevsky, Zeev

    2010-01-18

    The gyrator transform is a useful tool for optical information processing applications. In this work we propose a multi-stage phase retrieval approach based on this operation as well as on the well-known Gerchberg-Saxton algorithm. It results in an iterative algorithm able to retrieve the phase information using several measurements of the gyrator transform power spectrum. The viability and performance of the proposed algorithm is demonstrated by means of several numerical simulations and experimental results.

  1. Multi-stage phase retrieval algorithm based upon the gyrator transform

    OpenAIRE

    Rodrigo Martín-Romo, José Augusto; Duadi, Hamootal; Alieva, Tatiana Krasheninnikova; Zalevsky, Zeev

    2010-01-01

    The gyrator transform is a useful tool for optical information processing applications. In this work we propose a multi-stage phase retrieval approach based on this operation as well as on the well-known Gerchberg-Saxton algorithm. It results in an iterative algorithm able to retrieve the phase information using several measurements of the gyrator transform power spectrum. The viability and performance of the proposed algorithm is demonstrated by means of several numerical simulations and exp...

  2. Analysis for pressure transient of coalbed methane reservoir based on Laplace transform finite difference method

    OpenAIRE

    Lei Wang; Hongjun Yin; Xiaoshuang Yang; Chuncheng Yang; Jing Fu

    2015-01-01

    Based on fractal geometry, fractal medium of coalbed methane mathematical model is established by Langmuir isotherm adsorption formula, Fick's diffusion law, Laplace transform formula, considering the well bore storage effect and skin effect. The Laplace transform finite difference method is used to solve the mathematical model. With Stehfest numerical inversion, the distribution of dimensionless well bore flowing pressure and its derivative was obtained in real space. According to compare wi...

  3. Graph-based linear scaling electronic structure theory

    Energy Technology Data Exchange (ETDEWEB)

    Niklasson, Anders M. N., E-mail: amn@lanl.gov; Negre, Christian F. A.; Cawkwell, Marc J.; Swart, Pieter J.; Germann, Timothy C.; Bock, Nicolas [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Mniszewski, Susan M.; Mohd-Yusof, Jamal; Wall, Michael E.; Djidjev, Hristo [Computer, Computational, and Statistical Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Rubensson, Emanuel H. [Division of Scientific Computing, Department of Information Technology, Uppsala University, Box 337, SE-751 05 Uppsala (Sweden)

    2016-06-21

    We show how graph theory can be combined with quantum theory to calculate the electronic structure of large complex systems. The graph formalism is general and applicable to a broad range of electronic structure methods and materials, including challenging systems such as biomolecules. The methodology combines well-controlled accuracy, low computational cost, and natural low-communication parallelism. This combination addresses substantial shortcomings of linear scaling electronic structure theory, in particular with respect to quantum-based molecular dynamics simulations.

  4. Research of Measurement Circuits for High Voltage Current Transformer Based on Rogowski Coils

    Directory of Open Access Journals (Sweden)

    Yan Bing

    2014-02-01

    Full Text Available The electronic current transformer plays an irreplaceable position in the field of relay protection and current measurement of the power system. Rogowski coils are used as sensor parts, and in order to improve the measurement accuracy and reliability, the circuits at the high voltage system are introduced and improved in this paper, including the analog integral element, the filtering circuit and the phase shift circuit. Simulations results proved the reliability and accuracy of the improved circuits.

  5. Wind turbine transformer admittance characterization based on online time-domain measurements and preliminary results from measurements done in two transformers using a SFRA

    DEFF Research Database (Denmark)

    Arana Aristi, Iván; Holbøll, Joachim; Nielsen, Arne Hejde

    2009-01-01

    This paper presents the analysis of online time-domain measurements on the primary and secondary side of a wind turbine transformer in an Offshore Wind Farm (OWF), during one switching operation realized in the collection grid. The frequency characteristics up to 10 kHz of the current and voltage...... signals of each phase were compared and the transformers admittance characteristic was estimated based on these measurements. Based on the results from the previous analysis, it was decided to acquire a Sweep Frequency Response Analyzer (SFRA) to realize detailed transformer measurements. First...... the results from the measurements in a small dry-type transformer under laboratory conditions are presented, and finally the results from a large transformer measured in a in an industrial setting are shown....

  6. Direct electron transfer based enzymatic fuel cells

    International Nuclear Information System (INIS)

    Falk, Magnus; Blum, Zoltan; Shleev, Sergey

    2012-01-01

    In this mini-review we briefly describe some historical developments made in the field of enzymatic fuel cells (FCs), discussing important design considerations taken when constructing mediator-, cofactor-, and membrane-less biological FCs (BFCs). Since the topic is rather extensive, only BFCs utilizing direct electron transfer (DET) reactions on both the anodic and cathodic sides are considered. Moreover, the performance of mostly glucose/oxygen biodevices is analyzed and compared. We also present some unpublished results on mediator-, cofactor-, and membrane-less glucose/oxygen BFCs recently designed in our group and tested in different human physiological fluids, such as blood, plasma, saliva, and tears. Finally, further perspectives for BFC applications are highlighted.

  7. A Rapid Coordinate Transformation Method Applied in Industrial Robot Calibration Based on Characteristic Line Coincidence

    Science.gov (United States)

    Liu, Bailing; Zhang, Fumin; Qu, Xinghua; Shi, Xiaojia

    2016-01-01

    Coordinate transformation plays an indispensable role in industrial measurements, including photogrammetry, geodesy, laser 3-D measurement and robotics. The widely applied methods of coordinate transformation are generally based on solving the equations of point clouds. Despite the high accuracy, this might result in no solution due to the use of ill conditioned matrices. In this paper, a novel coordinate transformation method is proposed, not based on the equation solution but based on the geometric transformation. We construct characteristic lines to represent the coordinate systems. According to the space geometry relation, the characteristic line scan is made to coincide by a series of rotations and translations. The transformation matrix can be obtained using matrix transformation theory. Experiments are designed to compare the proposed method with other methods. The results show that the proposed method has the same high accuracy, but the operation is more convenient and flexible. A multi-sensor combined measurement system is also presented to improve the position accuracy of a robot with the calibration of the robot kinematic parameters. Experimental verification shows that the position accuracy of robot manipulator is improved by 45.8% with the proposed method and robot calibration. PMID:26901203

  8. A Rapid Coordinate Transformation Method Applied in Industrial Robot Calibration Based on Characteristic Line Coincidence

    Directory of Open Access Journals (Sweden)

    Bailing Liu

    2016-02-01

    Full Text Available Coordinate transformation plays an indispensable role in industrial measurements, including photogrammetry, geodesy, laser 3-D measurement and robotics. The widely applied methods of coordinate transformation are generally based on solving the equations of point clouds. Despite the high accuracy, this might result in no solution due to the use of ill conditioned matrices. In this paper, a novel coordinate transformation method is proposed, not based on the equation solution but based on the geometric transformation. We construct characteristic lines to represent the coordinate systems. According to the space geometry relation, the characteristic line scan is made to coincide by a series of rotations and translations. The transformation matrix can be obtained using matrix transformation theory. Experiments are designed to compare the proposed method with other methods. The results show that the proposed method has the same high accuracy, but the operation is more convenient and flexible. A multi-sensor combined measurement system is also presented to improve the position accuracy of a robot with the calibration of the robot kinematic parameters. Experimental verification shows that the position accuracy of robot manipulator is improved by 45.8% with the proposed method and robot calibration.

  9. Recent advances in carbon nanotube-based electronics

    International Nuclear Information System (INIS)

    Sharma, Prithu; Ahuja, Prerit

    2008-01-01

    CNT-electronics is a field involving synthesis of carbon nanotubes-based novel electronic circuits, comparable to the size of molecules, the practically fundamental size possible. It has brought a new paradigm in science as it has enabled scientists to increase the device integration density tremendously, hence achieving better efficiency and speed. Here we review the state-of-art current research on the applications of CNTs in electronics and present recent results outlining their potential along with illustrating some current concerns in the research field. Unconventional projects such as CNT-based biological sensors, transistors, field emitters, integrated circuits, etc. are taking CNT-based electronics to its extremes. The field holds a promise for mass production of high speed and efficient electronic devices. However, the chemical complexity, reproducibility and other factors make the field a challenging one, which need to be addressed before the field realizes its true potential

  10. Use of the Lorentz-Boosted Frame Transformation to Simulate Free-Electron Laser Amplifier Physics

    International Nuclear Information System (INIS)

    Fawley, W.M.; Vay, J.-L.

    2008-01-01

    Recently it has been pointed out that numerical simulation of some systems containing charged particles with highly relativistic directed motion can by speeded up by orders of magnitude by choice of the proper Lorentz boosted frame. A particularly good example is that of short wavelength free-electron lasers (FELs) in which a high energy (E0 (ge) 250 MeV) electron beam interacts with a static magnetic undulator. In the optimal boost frame with Lorentz factor gamma F, the red-shifted FEL radiation and blue shifted undulator have identical wavelengths and the number of required time-steps (presuming the Courant condition applies) decreases by a factor of g2 F for fully electromagnetic simulation. We have adapted the WARP code to apply this method to several FEL problems including coherent spontaneous emission (CSE) from pre-bunched e-beams, and strong exponential gain in a single pass amplifier configuration. We discuss our results and compare with those from the 'standard' FEL simulation approach which adopts the eikonal approximation for propagation of the radiation field

  11. Structural and electronic transformations in substituted La-Sr manganites depending on cations and oxygen content

    Science.gov (United States)

    Karpasyuk, Vladimir; Badelin, Alexey; Merkulov, Denis; Derzhavin, Igor; Estemirova, Svetlana

    2018-05-01

    In the present research experimental data are obtained for the Jahn-Teller O‧ phase formation, phase transformation "orthorhombic-rhombohedral structure" and the change of the conductance type in the systems of manganites La3+1-c+xSr2+c-xMn3+1-c-x-2γMn4+c+2γZn2+xO3+γ, La3+1-c-xSr2+c+xMn3+1-c-x-2γMn4+c+2γGe4+xO3+γ, La3+1-cSr2+cMn3+1-x-c-2γMn4+c+2γ(Zn2+0.5Ge4+0.5)xO3+γ, where Mn4+ ions concentration is independent of "x". Ceramic samples were sintered in air at 1473 K. As-sintered samples had an excess of oxygen content. In order to provide stoichiometric oxygen content, the samples were annealed at 1223 K and partial pressure of oxygen PO2 = 10-1 Pа. Structural characteristics of the O‧ phase were obtained. The position of the phase boundary "orthorhombic-rhombohedral structure" and the temperature of the conductance type change depending on the cation composition of manganites and oxygen content were determined. Possible approaches to the interpretation of experimental results were suggested.

  12. Exploring two-dimensional electron gases with two-dimensional Fourier transform spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Paul, J.; Dey, P.; Karaiskaj, D., E-mail: karaiskaj@usf.edu [Department of Physics, University of South Florida, 4202 East Fowler Ave., Tampa, Florida 33620 (United States); Tokumoto, T.; Hilton, D. J. [Department of Physics, University of Alabama at Birmingham, Birmingham, Alabama 35294 (United States); Reno, J. L. [CINT, Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

    2014-10-07

    The dephasing of the Fermi edge singularity excitations in two modulation doped single quantum wells of 12 nm and 18 nm thickness and in-well carrier concentration of ∼4 × 10{sup 11} cm{sup −2} was carefully measured using spectrally resolved four-wave mixing (FWM) and two-dimensional Fourier transform (2DFT) spectroscopy. Although the absorption at the Fermi edge is broad at this doping level, the spectrally resolved FWM shows narrow resonances. Two peaks are observed separated by the heavy hole/light hole energy splitting. Temperature dependent “rephasing” (S{sub 1}) 2DFT spectra show a rapid linear increase of the homogeneous linewidth with temperature. The dephasing rate increases faster with temperature in the narrower 12 nm quantum well, likely due to an increased carrier-phonon scattering rate. The S{sub 1} 2DFT spectra were measured using co-linear, cross-linear, and co-circular polarizations. Distinct 2DFT lineshapes were observed for co-linear and cross-linear polarizations, suggesting the existence of polarization dependent contributions. The “two-quantum coherence” (S{sub 3}) 2DFT spectra for the 12 nm quantum well show a single peak for both co-linear and co-circular polarizations.

  13. Single-stage unity power factor based electronic ballast

    Indian Academy of Sciences (India)

    This paper deals with the design, modeling, analysis and implementation of unity power factor (UPF) based electronic ballast for a fluorescent lamp (FL). The proposed electronic ballast uses a boost AC–DC converter as a power factor corrector (PFC) to improve the power quality at the input ac mains. In this singlestage ...

  14. Subsurface characterization of an oxidation-induced phase transformation and twinning in nickel-based superalloy exposed to oxy-combustion environments

    International Nuclear Information System (INIS)

    Zhu Jingxi; Holcomb, Gordon R.; Jablonski, Paul D.; Wise, Adam; Li Jia; Laughlin, David E.; Sridhar, Seetharaman

    2012-01-01

    Highlights: ►Oxidation products of Ni-based superalloy were studied in oxy-fuel combustion conditions. ► An oxidation-induced phase transformation occurred in the subsurface region. ► One of the two product phases was not in the Ni database of Thermo-Calc. ► This unknown phase is an ordered derivative of FCC structure of Ni–Ti(–Ta) system. ► This phase is likely detrimental to the mechanical integrity of the alloy in use. - Abstract: In the integration of oxy-fuel combustion to turbine power generation system, turbine alloys are exposed to high temperature and an atmosphere comprised of steam, CO 2 and O 2 . While surface and internal oxidation of the alloy takes place, the microstructure in the subsurface region also changes due to oxidation. In this study, bare metal coupons of Ni-base superalloys were exposed in oxy-fuel combustion environment for up to 1000 h and the oxidation-related microstructures were examined. Phase transformation occurred in the subsurface region in Ni-based superalloy and led to twinning. The transformation product phases were analyzed through thermodynamic equilibrium calculations and various electron microscopy techniques, including scanning electron microscopy (SEM), orientation imaging microscopy (OIM) and transmission electron microscopy (TEM). The mechanism by which the phase transformation and the formation of the microstructure occurred was also discussed. The possible effects of the product phases on the performance of the alloy in service were discussed.

  15. Dihydropyrroloindoledione-based copolymers for organic electronics

    NARCIS (Netherlands)

    Rumer, JW; Dai, SY; Levick, M; Young Kim, Young; Madec, MB; Ashraf, R.S.; Huang, Z.; Rossbauer, S; Schroeder, B.; Biniek, L; Watkins, S.E.; Anthopoulos, T.D.; Janssen, R.A.J.; Durrant, J.R.; Procter, DJ; McCulloch, I.

    2013-01-01

    A series of four dihydropyrroloindoledione-based organic semi-conducting polymers are examined for performance in transistor and photovoltaic cell devices. The dihydropyrroloindoledione unit was alternately copolymerized with phenyl, thiophene and bithiophene comonomers, and the resultant polymers

  16. Content-based video indexing and searching with wavelet transformation

    Science.gov (United States)

    Stumpf, Florian; Al-Jawad, Naseer; Du, Hongbo; Jassim, Sabah

    2006-05-01

    Biometric databases form an essential tool in the fight against international terrorism, organised crime and fraud. Various government and law enforcement agencies have their own biometric databases consisting of combination of fingerprints, Iris codes, face images/videos and speech records for an increasing number of persons. In many cases personal data linked to biometric records are incomplete and/or inaccurate. Besides, biometric data in different databases for the same individual may be recorded with different personal details. Following the recent terrorist atrocities, law enforcing agencies collaborate more than before and have greater reliance on database sharing. In such an environment, reliable biometric-based identification must not only determine who you are but also who else you are. In this paper we propose a compact content-based video signature and indexing scheme that can facilitate retrieval of multiple records in face biometric databases that belong to the same person even if their associated personal data are inconsistent. We shall assess the performance of our system using a benchmark audio visual face biometric database that has multiple videos for each subject but with different identity claims. We shall demonstrate that retrieval of relatively small number of videos that are nearest, in terms of the proposed index, to any video in the database results in significant proportion of that individual biometric data.

  17. Improved l1-SPIRiT using 3D walsh transform-based sparsity basis.

    Science.gov (United States)

    Feng, Zhen; Liu, Feng; Jiang, Mingfeng; Crozier, Stuart; Guo, He; Wang, Yuxin

    2014-09-01

    l1-SPIRiT is a fast magnetic resonance imaging (MRI) method which combines parallel imaging (PI) with compressed sensing (CS) by performing a joint l1-norm and l2-norm optimization procedure. The original l1-SPIRiT method uses two-dimensional (2D) Wavelet transform to exploit the intra-coil data redundancies and a joint sparsity model to exploit the inter-coil data redundancies. In this work, we propose to stack all the coil images into a three-dimensional (3D) matrix, and then a novel 3D Walsh transform-based sparsity basis is applied to simultaneously reduce the intra-coil and inter-coil data redundancies. Both the 2D Wavelet transform-based and the proposed 3D Walsh transform-based sparsity bases were investigated in the l1-SPIRiT method. The experimental results show that the proposed 3D Walsh transform-based l1-SPIRiT method outperformed the original l1-SPIRiT in terms of image quality and computational efficiency. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Evaluating Pillar Industry's Transformation Capability: A Case Study of Two Chinese Steel-Based Cities.

    Science.gov (United States)

    Li, Zhidong; Marinova, Dora; Guo, Xiumei; Gao, Yuan

    2015-01-01

    Many steel-based cities in China were established between the 1950s and 1960s. After more than half a century of development and boom, these cities are starting to decline and industrial transformation is urgently needed. This paper focuses on evaluating the transformation capability of resource-based cities building an evaluation model. Using Text Mining and the Document Explorer technique as a way of extracting text features, the 200 most frequently used words are derived from 100 publications related to steel- and other resource-based cities. The Expert Evaluation Method (EEM) and Analytic Hierarchy Process (AHP) techniques are then applied to select 53 indicators, determine their weights and establish an index system for evaluating the transformation capability of the pillar industry of China's steel-based cities. Using real data and expert reviews, the improved Fuzzy Relation Matrix (FRM) method is applied to two case studies in China, namely Panzhihua and Daye, and the evaluation model is developed using Fuzzy Comprehensive Evaluation (FCE). The cities' abilities to carry out industrial transformation are evaluated with concerns expressed for the case of Daye. The findings have policy implications for the potential and required industrial transformation in the two selected cities and other resource-based towns.

  19. Phase-based motion magnification video for monitoring of vital signals using the Hermite transform

    Science.gov (United States)

    Brieva, Jorge; Moya-Albor, Ernesto

    2017-11-01

    In this paper we present a new Eulerian phase-based motion magnification technique using the Hermite Transform (HT) decomposition that is inspired in the Human Vision System (HVS). We test our method in one sequence of the breathing of a newborn baby and on a video sequence that shows the heartbeat on the wrist. We detect and magnify the heart pulse applying our technique. Our motion magnification approach is compared to the Laplacian phase based approach by means of quantitative metrics (based on the RMS error and the Fourier transform) to measure the quality of both reconstruction and magnification. In addition a noise robustness analysis is performed for the two methods.

  20. A general method for baseline-removal in ultrafast electron powder diffraction data using the dual-tree complex wavelet transform

    Directory of Open Access Journals (Sweden)

    Laurent P. René de Cotret

    2017-07-01

    Full Text Available The general problem of background subtraction in ultrafast electron powder diffraction (UEPD is presented with a focus on the diffraction patterns obtained from materials of moderately complex structure which contain many overlapping peaks and effectively no scattering vector regions that can be considered exclusively background. We compare the performance of background subtraction algorithms based on discrete and dual-tree complex (DTCWT wavelet transforms when applied to simulated UEPD data on the M1–R phase transition in VO2 with a time-varying background. We find that the DTCWT approach is capable of extracting intensities that are accurate to better than 2% across the whole range of scattering vector simulated, effectively independent of delay time. A Python package is available.

  1. The Use of Continuous Wavelet Transform Based on the Fast Fourier Transform in the Analysis of Multi-channel Electrogastrography Recordings.

    Science.gov (United States)

    Komorowski, Dariusz; Pietraszek, Stanislaw

    2016-01-01

    This paper presents the analysis of multi-channel electrogastrographic (EGG) signals using the continuous wavelet transform based on the fast Fourier transform (CWTFT). The EGG analysis was based on the determination of the several signal parameters such as dominant frequency (DF), dominant power (DP) and index of normogastria (NI). The use of continuous wavelet transform (CWT) allows for better visible localization of the frequency components in the analyzed signals, than commonly used short-time Fourier transform (STFT). Such an analysis is possible by means of a variable width window, which corresponds to the scale time of observation (analysis). Wavelet analysis allows using long time windows when we need more precise low-frequency information, and shorter when we need high frequency information. Since the classic CWT transform requires considerable computing power and time, especially while applying it to the analysis of long signals, the authors used the CWT analysis based on the fast Fourier transform (FFT). The CWT was obtained using properties of the circular convolution to improve the speed of calculation. This method allows to obtain results for relatively long records of EGG in a fairly short time, much faster than using the classical methods based on running spectrum analysis (RSA). In this study authors indicate the possibility of a parametric analysis of EGG signals using continuous wavelet transform which is the completely new solution. The results obtained with the described method are shown in the example of an analysis of four-channel EGG recordings, performed for a non-caloric meal.

  2. Low temperature electron microscopy on the cubic-tetragonal transformation of V3Si

    Science.gov (United States)

    Onozuka, T.; Ohnishi, N.; Hirabayashi, M.

    1988-04-01

    The cubic-tetragonal martensitic transition of V3Si and its precursor have been investigated in the temperature range from 13 K to 80 K using a 1 MV electron microscope with a double-tilting cold stage. Below the transition temperature Tm = 19 K, fine twin lamellae appear parallel to {110} plane traces, being connected continuously with mottled striations having the same orientation. Fine striations along {110} traces or so-called tweeds are observed below 50 K at the precursor of the structural phase transition. The image contrast of mottled striations and tweed patterns is attributed to the presence of lattice distortion owing to the softening of the shear modulus. Reversible changes of the patterns recorded with a TV-VTR system during cooling and heating processes were discussed briefly.

  3. Transgressing the norm: Transformative agency in community-based learning for sustainability in southern African contexts

    Science.gov (United States)

    Lotz-Sisitka, Heila; Mukute, Mutizwa; Chikunda, Charles; Baloi, Aristides; Pesanayi, Tichaona

    2017-12-01

    Environment and sustainability education processes are often oriented to change and transformation, and frequently involve the emergence of new forms of human activity. However, not much is known about how such change emerges from the learning process, or how it contributes to the development of transformative agency in community contexts. The authors of this article present four cross-case perspectives of expansive learning and transformative agency development in community-based education in southern Africa, studying communities pursuing new activities that are more socially just and sustainable. The four cases of community learning and transformative agency focus on the following activities: (1) sustainable agriculture in Lesotho; (2) seed saving and rainwater harvesting in Zimbabwe; (3) community-based irrigation scheme management in Mozambique; and (4) biodiversity conservation co-management in South Africa. The case studies all draw on cultural-historical activity theory to guide learning and change processes, especially third-generation cultural-historical activity theory (CHAT), which emphasises expansive learning in collectives across interacting activity systems. CHAT researchers, such as the authors of this article, argue that expansive learning can lead to the emergence of transformative agency. The authors extend their transformative agency analysis to probe if and how expansive learning might also facilitate instances of transgressing norms - viewed here as embedded practices which need to be reframed and changed in order for sustainability to emerge.

  4. Quantum image encryption based on generalized affine transform and logistic map

    Science.gov (United States)

    Liang, Hao-Ran; Tao, Xiang-Yang; Zhou, Nan-Run

    2016-07-01

    Quantum circuits of the generalized affine transform are devised based on the novel enhanced quantum representation of digital images. A novel quantum image encryption algorithm combining the generalized affine transform with logistic map is suggested. The gray-level information of the quantum image is encrypted by the XOR operation with a key generator controlled by the logistic map, while the position information of the quantum image is encoded by the generalized affine transform. The encryption keys include the independent control parameters used in the generalized affine transform and the logistic map. Thus, the key space is large enough to frustrate the possible brute-force attack. Numerical simulations and analyses indicate that the proposed algorithm is realizable, robust and has a better performance than its classical counterpart in terms of computational complexity.

  5. How Does Environmental Regulation Affect Industrial Transformation? A Study Based on the Methodology of Policy Simulation

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2016-01-01

    Full Text Available The difference of factor input structure determines different response to environmental regulation. This paper constructs a theoretical model including environmental regulation, factor input structure, and industrial transformation and conducts a policy simulation based on the difference of influencing mechanism of environmental regulation considering industrial heterogeneity. The findings show that the impact of environmental regulation on industrial transformation presents comparison of distortion effect of resource allocation and technology effect. Environmental regulation will promote industrial transformation when technology effect of environmental regulation is stronger than distortion effect of resource allocation. Particularly, command-control environmental regulation has a significant incentive effect and spillover effect of technological innovation on cleaning industries, but these effects do not exist in pollution-intensive industries. Command-control environmental regulation promotes industrial transformation. The result of simulation showed that environmental regulation of market incentives is similar to that of command-control.

  6. A Precise Lane Detection Algorithm Based on Top View Image Transformation and Least-Square Approaches

    Directory of Open Access Journals (Sweden)

    Byambaa Dorj

    2016-01-01

    Full Text Available The next promising key issue of the automobile development is a self-driving technique. One of the challenges for intelligent self-driving includes a lane-detecting and lane-keeping capability for advanced driver assistance systems. This paper introduces an efficient and lane detection method designed based on top view image transformation that converts an image from a front view to a top view space. After the top view image transformation, a Hough transformation technique is integrated by using a parabolic model of a curved lane in order to estimate a parametric model of the lane in the top view space. The parameters of the parabolic model are estimated by utilizing a least-square approach. The experimental results show that the newly proposed lane detection method with the top view transformation is very effective in estimating a sharp and curved lane leading to a precise self-driving capability.

  7. Transformational and Transactional Leadership: Association With Attitudes Toward Evidence-Based Practice

    Science.gov (United States)

    Aarons, Gregory A.

    2006-01-01

    Objective Leadership in organizations is important in shaping workers’ perceptions, responses to organizational change, and acceptance of innovations, such as evidence-based practices. Transformational leadership inspires and motivates followers, whereas transactional leadership is based more on reinforcement and exchanges. Studies have shown that in youth and family service organizations, mental health providers’ attitudes toward adopting an evidence-based practice are associated with organizational context and individual provider differences. The purpose of this study was to expand these findings by examining the association between leadership and mental health providers’ attitudes toward adopting evidence-based practice. Methods Participants were 303 public-sector mental health service clinicians and case managers from 49 programs who were providing mental health services to children, adolescents, and their families. Data were gathered on providers’ characteristics, attitudes toward evidence-based practices, and perceptions of their supervisors’ leadership behaviors. Zero-order correlations and multilevel regression analyses were conducted that controlled for effects of service providers’ characteristics. Results Both transformational and transactional leadership were positively associated with providers’ having more positive attitudes toward adoption of evidence-based practice, and transformational leadership was negatively associated with providers’ perception of difference between the providers’ current practice and evidence-based practice. Conclusions Mental health service organizations may benefit from improving transformational and transactional supervisory leadership skills in preparation for implementing evidence-based practices. PMID:16870968

  8. Calibration Base Lines for Electronic Distance Measuring Instruments (EDMI)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A calibration base line (CBL) is a precisely measured, straight-line course of approximately 1,400 m used to calibrate Electronic Distance Measuring Instruments...

  9. Nitrogen transformations in a waterhyacinth-based water treatment system

    International Nuclear Information System (INIS)

    Moorhead, K.K.; Reddy, K.R.; Graetz, D.A.

    1988-01-01

    Fate of added 15 NH 4 -N and 15 NO 3 -N in waterhyacinth [Eichhornia crassipes (Mart.) Solms]-based water treatment system was evaluated under controlled conditions. Labeled 15 NH 4 -N uptake by waterhyacinth exceeded 15 NO 3 -N uptake. Total 15 N recovery by waterhyacinth ranged from 57 to 72% for added 15 NO 3 -N and 70 to 89% for added 15 NH 4 -N. Both sediment and detritus were potential sources of N for waterhyacinths. Waterhyacinths cultured in sewage effluent removed 55% of the added 15 NH 4 -N and 14% of the added 15 NO 3 -N, respectively. Three to 44% of the added 15 NH 4 -N was lost through nitrification in the water column and subsequent denitrification in the underlying sediments, whereas 24 to 86% of the added 15 NO 3 -N was lost through denitrification. In a system without plants, 13 to 89% of the added 15 NH 4 -N and 48 to 96% of the added 15 NO 3 -N were lost from the system through a combination of nitrification/denitrification and NH 3 volatilization

  10. Backstepping Based Formation Control of Quadrotors with the State Transformation Technique

    Directory of Open Access Journals (Sweden)

    Keun Uk Lee

    2017-11-01

    Full Text Available In this paper, a backstepping-based formation control of quadrotors with the state transformation technique is proposed. First, the dynamics of a quadrotor is derived by using the Newton–Euler formulation. Next, a backstepping-based formation control for quadrotors using a state transformation technique is presented. In the position control, which is the basis of formation control, it is possible to derive the reference attitude angles employing a state transformation technique without the small angle assumption or the simplified dynamics usually used. Stability analysis based on the Lyapunov theorem shows that the proposed formation controller can provide a quadrotor formation error system that is asymptotically stabilized. Finally, we verify the performance of the proposed formation control method through comparison simulations.

  11. In situ studies of oxide nucleation, growth, and transformation using slow electrons

    Science.gov (United States)

    Flege, Jan Ingo; Grinter, David C.

    2018-05-01

    Surface processes such as metal oxidation and metal oxide growth invariably influence the physical and chemical properties of materials and determine their interaction with their surroundings and hence their functionality in many technical applications. On a fundamental level, these processes are found to be governed by a complex interplay of thermodynamic variables and kinetic constraints, resulting in a rich variety of material-specific phenomena. In this review article, we discuss recent results and insights on transition metal oxidation and rare-earth oxide growth acquired by low-energy electron microscopy and related techniques. We demonstrate that the use of in situ surface sensitive methods is a prerequisite to gaining a deeper understanding of the underlying concepts and the mechanisms responsible for the emerging oxide structure and morphology. Furthermore, examples will be provided on how structural and chemical modifications of the oxide films and nanostructures can be followed in real-time and analyzed in terms of local reactivity and cooperative effects relevant for heterogeneous model catalysis.

  12. OTDM-WDM Conversion Based on Time-Domain Optical Fourier Transformation with Spectral Compression

    DEFF Research Database (Denmark)

    Mulvad, Hans Christian Hansen; Palushani, Evarist; Galili, Michael

    2011-01-01

    We propose a scheme enabling direct serial-to-parallel conversion of OTDM data tributaries onto a WDM grid, based on optical Fourier transformation with spectral compression. Demonstrations on 320 Gbit/s and 640 Gbit/s OTDM data are shown.......We propose a scheme enabling direct serial-to-parallel conversion of OTDM data tributaries onto a WDM grid, based on optical Fourier transformation with spectral compression. Demonstrations on 320 Gbit/s and 640 Gbit/s OTDM data are shown....

  13. Deficiencies of the cryptography based on multiple-parameter fractional Fourier transform.

    Science.gov (United States)

    Ran, Qiwen; Zhang, Haiying; Zhang, Jin; Tan, Liying; Ma, Jing

    2009-06-01

    Methods of image encryption based on fractional Fourier transform have an incipient flaw in security. We show that the schemes have the deficiency that one group of encryption keys has many groups of keys to decrypt the encrypted image correctly for several reasons. In some schemes, many factors result in the deficiencies, such as the encryption scheme based on multiple-parameter fractional Fourier transform [Opt. Lett.33, 581 (2008)]. A modified method is proposed to avoid all the deficiencies. Security and reliability are greatly improved without increasing the complexity of the encryption process. (c) 2009 Optical Society of America.

  14. Empiric analysis of zero voltage switching in piezoelectric transformer based resonant converters

    DEFF Research Database (Denmark)

    Rødgaard, Martin Schøler; Andersen, Thomas; Andersen, Michael A. E.

    2012-01-01

    Research and development within piezoelectric transformer (PT) based converters are rapidly increasing, as the technology is maturing and starts to prove its capabilities. High power density and high efficiencies are reported and recently several inductor-less converters have emerged [1][2][7][10......Research and development within piezoelectric transformer (PT) based converters are rapidly increasing, as the technology is maturing and starts to prove its capabilities. High power density and high efficiencies are reported and recently several inductor-less converters have emerged [1...

  15. Determination of sulfur compounds in hydrotreated transformer base oil by potentiometric titration.

    Science.gov (United States)

    Chao, Qiu; Sheng, Han; Cheng, Xingguo; Ren, Tianhui

    2005-06-01

    A method was developed to analyze the distribution of sulfur compounds in model sulfur compounds by potentiometric titration, and applied to analyze hydrotreated transformer base oil. Model thioethers were oxidized to corresponding sulfoxides by tetrabutylammonium periodate and sodium metaperiodate, respectively, and the sulfoxides were titrated by perchloric acid titrant in acetic anhydride. The contents of aliphatic thioethers and total thioethers were then determined from that of sulfoxides in solution. The method was applied to determine the organic sulfur compounds in hydrotreated transformer base oil.

  16. Phase-transformation and subgrain-deformation characteristics in a cobalt-based superalloy

    International Nuclear Information System (INIS)

    Benson, M.L.; Reetz, B.; Liaw, P.K.; Reimers, W.; Choo, H.; Brown, D.W.; Saleh, T.A.; Klarstrom, D.L.

    2011-01-01

    Research highlights: → The mechanical behavior of a cobalt-based superalloy was investigated. → Two diffraction techniques were used to study deformation mechanisms of materials. → In-situ neutron diffraction provides the volume-averaged information. → The peak-profile analysis reveals the information on a subgrain level. → The material exhibited a transformation texture for the HCP phase under loading. - Abstract: A complimentary set of experiments, in situ neutron diffraction and ex situ synchrotron X-ray diffraction, were used to study the phase-transformation and subgrain-deformation characteristics of a cobalt-based superalloy. The neutron diffraction indicated a strain-induced phase transformation in the cobalt-based superalloy under uniaxial tension and compression. The synchrotron X-ray diffraction revealed stacking-fault accumulation and twinning under the same loading conditions. The extent of transformation was found to be greater under tension than under compression. Tensile plastic strains below 2% were accommodated by the stacking-fault creation, while those greater than 2% were accommodated by the phase transformation. Twinning was found to be more active under compressive loading than under tensile loading.

  17. Chameleons in Marketspace: Industry Transformation in the New Electronic Marketing Environment.

    Science.gov (United States)

    Pattinson, Hugh; Brown, Linden

    1996-01-01

    Discusses the new information infrastructure and its possible influences on marketing. Highlights include an alternative perspective of industrial economic history based on infrastructure development; the Internet and its positioning within the new information infrastructure; future possibilities and impacts on organizational structure; and…

  18. Controlled cooling of an electronic system based on projected conditions

    Science.gov (United States)

    David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.

    2015-08-18

    Energy efficient control of a cooling system cooling an electronic system is provided based, in part, on projected conditions. The control includes automatically determining an adjusted control setting(s) for an adjustable cooling component(s) of the cooling system. The automatically determining is based, at least in part, on projected power consumed by the electronic system at a future time and projected temperature at the future time of a heat sink to which heat extracted is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the cooling system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on an experimentally obtained model(s) relating the targeted temperature and power consumption of the adjustable cooling component(s) of the cooling system.

  19. Performance Evaluation of Frequency Transform Based Block Classification of Compound Image Segmentation Techniques

    Science.gov (United States)

    Selwyn, Ebenezer Juliet; Florinabel, D. Jemi

    2018-04-01

    Compound image segmentation plays a vital role in the compression of computer screen images. Computer screen images are images which are mixed with textual, graphical, or pictorial contents. In this paper, we present a comparison of two transform based block classification of compound images based on metrics like speed of classification, precision and recall rate. Block based classification approaches normally divide the compound images into fixed size blocks of non-overlapping in nature. Then frequency transform like Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT) are applied over each block. Mean and standard deviation are computed for each 8 × 8 block and are used as features set to classify the compound images into text/graphics and picture/background block. The classification accuracy of block classification based segmentation techniques are measured by evaluation metrics like precision and recall rate. Compound images of smooth background and complex background images containing text of varying size, colour and orientation are considered for testing. Experimental evidence shows that the DWT based segmentation provides significant improvement in recall rate and precision rate approximately 2.3% than DCT based segmentation with an increase in block classification time for both smooth and complex background images.

  20. Wavelet Based Hilbert Transform with Digital Design and Application to QCM-SS Watermarking

    Directory of Open Access Journals (Sweden)

    S. P. Maity

    2008-04-01

    Full Text Available In recent time, wavelet transforms are used extensively for efficient storage, transmission and representation of multimedia signals. Hilbert transform pairs of wavelets is the basic unit of many wavelet theories such as complex filter banks, complex wavelet and phaselet etc. Moreover, Hilbert transform finds various applications in communications and signal processing such as generation of single sideband (SSB modulation, quadrature carrier multiplexing (QCM and bandpass representation of a signal. Thus wavelet based discrete Hilbert transform design draws much attention of researchers for couple of years. This paper proposes an (i algorithm for generation of low computation cost Hilbert transform pairs of symmetric filter coefficients using biorthogonal wavelets, (ii approximation to its rational coefficients form for its efficient hardware realization and without much loss in signal representation, and finally (iii development of QCM-SS (spread spectrum image watermarking scheme for doubling the payload capacity. Simulation results show novelty of the proposed Hilbert transform design and its application to watermarking compared to existing algorithms.

  1. Femtosecond pulse radiolysis based on photocathode electron accelerator

    International Nuclear Information System (INIS)

    Yoshida, Y.; Yang, Jinfeng; Kondoh, T.; Kozawa, T.; Tagawa, S.

    2006-01-01

    Pulse radiolysis is a powerful tool for studying chemical kinetics and primary processes or reactions of radiation chemistry. In the pulse radiolysis, a short electron beam, which is almost produced by radio-frequency (RF) electron linear accelerator with energy from a few MeV to a few tens MeV, is used as an irradiative source. The electron-induced reactions or phenomena in matter are analyzed by a short-pulse analyzing light (e.g. synchronized lasers) with the time-resolved stroboscopic technique. The time resolution of pulse radiolysis is not only dependent on the electron bunch length, the analyzing light pulse width, the time jitter between the electron bunch and the analyzing light, but also determined by degradation due to the velocity difference between light and the electron in the sample because of the refractive index. In order to improve the time resolution into femtosecond time region, we have develop a new pulse radiolysis based on a concept of 'Equivalent Velocity Spectroscopy (EVS)' to avoid the degradation of the time resolution caused by the velocity difference between the light and the electron beam in sample. In EVS as shown in Fig.1, a femtosecond electron beam produced by a photocathode electron linear accelerator was used, and a synchronized femtosecond laser was used as the analyzing light source. The electron beam and the laser light were injected into sample with an angle (θ), which is determined by the refractive index (n) of the sample. The electron bunch was also rotated with a same angle to make an overlap of the electron bunch with the laser pulse. The degradation of the time resolution caused by the velocity difference between the light and the electron beam can be calculated as g(L)=L[n/c-1/(vcos θ)], where L is the optical path length and v is the velocity of the electron in sample (we can assume v=c for a few tens MeV electron beam).We can thus obtained g(L)=0 by adjusting the incident angle to cos θ=1/n. However, the rotation

  2. Electrical-Based Diagnostic Techniques for Assessing Insulation Condition in Aged Transformers

    Directory of Open Access Journals (Sweden)

    Issouf Fofana

    2016-08-01

    Full Text Available The condition of the internal cellulosic paper and oil insulation are of concern for the performance of power transformers. Over the years, a number of methods have been developed to diagnose and monitor the degradation/aging of the transformer internal insulation system. Some of this degradation/aging can be assessed from electrical responses. Currently there are a variety of electrical-based diagnostic techniques available for insulation condition monitoring of power transformers. In most cases, the electrical signals being monitored are due to mechanical or electric changes caused by physical changes in resistivity, inductance or capacitance, moisture, contamination or aging by-products in the insulation. This paper presents a description of commonly used and modern electrical-based diagnostic techniques along with their interpretation schemes.

  3. Mobile phone base station radiation does not affect neoplastic transformation in BALB/3T3 cells.

    Science.gov (United States)

    Hirose, H; Suhara, T; Kaji, N; Sakuma, N; Sekijima, M; Nojima, T; Miyakoshi, J

    2008-01-01

    A large-scale in vitro study focusing on low-level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system was conducted to test the hypothesis that modulated RF fields affect malignant transformation or other cellular stress responses. Our group previously reported that DNA strand breaks were not induced in human cells exposed to 2.1425 GHz Wideband Code Division Multiple Access (W-CDMA) radiation up to 800 mW/kg from mobile radio base stations employing the IMT-2000 cellular system. In the current study, BALB/3T3 cells were continuously exposed to 2.1425 GHz W-CDMA RF fields at specific absorption rates (SARs) of 80 and 800 mW/kg for 6 weeks and malignant cell transformation was assessed. In addition, 3-methylcholanthrene (MCA)-treated cells were exposed to RF fields in a similar fashion, to assess for effects on tumor promotion. Finally, the effect of RF fields on tumor co-promotion was assessed in BALB/3T3 cells initiated with MCA and co-exposed to 12-O-tetradecanoylphorbol-13-acetate (TPA). At the end of the incubation period, transformation dishes were fixed, stained with Giemsa, and scored for morphologically transformed foci. No significant differences in transformation frequency were observed between the test groups exposed to RF signals and the sham-exposed negative controls in the non-, MCA-, or MCA plus TPA-treated cells. Our studies found no evidence to support the hypothesis that RF fields may affect malignant transformation. Our results suggest that exposure to low-level RF radiation of up to 800 mW/kg does not induce cell transformation, which causes tumor formation. (c) 2007 Wiley-Liss, Inc.

  4. Improving Computational Efficiency of Prediction in Model-Based Prognostics Using the Unscented Transform

    Science.gov (United States)

    Daigle, Matthew John; Goebel, Kai Frank

    2010-01-01

    Model-based prognostics captures system knowledge in the form of physics-based models of components, and how they fail, in order to obtain accurate predictions of end of life (EOL). EOL is predicted based on the estimated current state distribution of a component and expected profiles of future usage. In general, this requires simulations of the component using the underlying models. In this paper, we develop a simulation-based prediction methodology that achieves computational efficiency by performing only the minimal number of simulations needed in order to accurately approximate the mean and variance of the complete EOL distribution. This is performed through the use of the unscented transform, which predicts the means and covariances of a distribution passed through a nonlinear transformation. In this case, the EOL simulation acts as that nonlinear transformation. In this paper, we review the unscented transform, and describe how this concept is applied to efficient EOL prediction. As a case study, we develop a physics-based model of a solenoid valve, and perform simulation experiments to demonstrate improved computational efficiency without sacrificing prediction accuracy.

  5. Lipid-Based Liquid Crystalline Nanoparticles Facilitate Cytosolic Delivery of siRNA via Structural Transformation.

    Science.gov (United States)

    He, Shufang; Fan, Weiwei; Wu, Na; Zhu, Jingjing; Miao, Yunqiu; Miao, Xiaran; Li, Feifei; Zhang, Xinxin; Gan, Yong

    2018-04-11

    RNA interference (RNAi) technology has shown great promise for the treatment of cancer and other genetic disorders. Despite the efforts to increase the target tissue distribution, the safe and effective delivery of siRNA to the diseased cells with sufficient cytosolic transport is another critical factor for successful RNAi clinical application. Here, the constructed lipid-based liquid crystalline nanoparticles, called nano-Transformers, can transform thestructure in the intracellular acidic environment and perform high-efficient siRNA delivery for cancer treatment. The developed nano-Transformers have satisfactory siRNA loading efficiency and low cytotoxicity. Different from the traditional cationic nanocarriers, the endosomal membrane fusion induced by the conformational transition of lipids contributes to the easy dissociation of siRNA from nanocarriers and direct release of free siRNA into cytoplasm. We show that transfection with cyclin-dependent kinase 1 (CDK1)-siRNA-loaded nano-Transformers causes up to 95% reduction of relevant mRNA in vitro and greatly inhibits the tumor growth without causing any immunogenic response in vivo. This work highlights that the lipid-based nano-Transformers may become the next generation of siRNA delivery system with higher efficacy and improved safety profiles.

  6. Design parameter based method of partial discharge detection and location in power transformers

    Directory of Open Access Journals (Sweden)

    Kumar Santosh Annadurai

    2009-01-01

    Full Text Available Insulation defect detection in time ensures higher operational reliability of power system assets. Power transformers are the most critical unit of power systems both from economical and operational front. Hence it becomes necessary to have knowledge of the actual insulation condition of transformer to increase dependability of the system. The performance and ageing of the transformer insulation is mainly affected by Partial discharges (PD. Proper diagnosis in terms of amplitude and location of partial discharge in a power transformer enables us to predict well in advance, with much confidence, the defect in insulation system, which avoids large catastrophic failures. In this work a 20kVA, 230/50kV single phase core type transformer is used for evaluation of the transfer function-based partial discharge detection and location using modeling of the winding, using design data. The simulation of capturing on-line PD pulses across the bushing tap capacitor is done for various tap positions. Standard PD source model is used to inject PD pulse signal at 10 tap locations in the winding and corresponding response signatures are captured at the bushing tap end (across 1000pF. The equivalent high frequency model of the winding is derived from the design parameters using analytical calculations and simulations in packages such as MAGNET and ANSOFT. The test conditions are simulated using ORCAD-9 and the results are evaluated for location accuracy using design parameter based PD monitoring method. .

  7. A Review on Properties, Opportunities, and Challenges of Transformer Oil-Based Nanofluids

    Directory of Open Access Journals (Sweden)

    Muhammad Rafiq

    2016-01-01

    Full Text Available The mineral oil or synthetic oil in conjunction with paper is mainly being applied as dielectric medium in many of the high voltage apparatus. However, the advent of high voltage levels such high voltage alternating current (HVAC and high voltage direct current (HVDC has prompted researchers to direct their focus onto an insulation system which can bear the rising high voltage levels. The modern insulating liquid material development is guided by various factors such as high electrical insulation requirements and other safety and economic considerations. Therefore transformer manufacturer companies have to design transformers with these new specific requirements. The transformer oil-based nanofluids with improved dielectric and thermal properties have the potential to replace mineral oil base products in the market place. They are favorable because they function more superior than mineral oil and they contribute definite insulating and thermal gains. This paper reviews recent status of nanofluids use as transformer oils. The nanofluids used as transformer oils are presented and their advantages are described in comparison with mineral oil. The multiple experimental works carried out by different researchers are described, providing an overview of the current research conducted on nanofluids. In addition scope and challenges being confronted in this area of research are clearly presented.

  8. Idea-based, transformative experiences in science: What are they and how do you foster them?

    Science.gov (United States)

    Pugh, Kevin James

    Many have argued that science education should enrich students' lives, but, surprisingly, this issue has not been systematically addressed. Much of the work in science education has focused on the issue of how enriched experience leads to the development of conceptual understanding, but relatively little work has focused on the issue of how conceptual understanding leads to the development of enriched experience. This dissertation is comprised of two articles, which address the latter issue. The first article, entitled "Applying Pragmatism and Deweyan Aesthetics to Science Education: A Look at How Concepts Can Enrich Everyday Experience," develops the construct of an idea-based, transformative experience (a particular type of enriched experience) and an understanding of the role that concepts play in such experience, by synthesizing Dewey's writings on experience, aesthetics, and education. Such experience is centrally defined by an expansion of perception, meaning, and value which results from active use of a concept. Three illustrative examples of idea-based, transformative experiences are provided. Implications include a focus on idea-based, transformative experience as the goal of science education. A discussion of how this goal compares, contrasts, and relates to the standard goals of conceptual understanding/change and the development of thinking/participatory skills is provided. The second article, entitled, "Teaching for Idea-based, Transformative Experiences in Science," is a report of a study which examines the effectiveness of two related teaching elements (the artistic crafting of content and the modeling and scaffolding of perception, meaning, and value) at fostering idea-based, transformative experiences. The elements were used in teaching a unit on adaptation and evolution in a high school zoology class and student outcomes were compared with those of students in a roughly equivalent class where case-based methods were used. Results indicate that a

  9. Archetype-based data warehouse environment to enable the reuse of electronic health record data.

    Science.gov (United States)

    Marco-Ruiz, Luis; Moner, David; Maldonado, José A; Kolstrup, Nils; Bellika, Johan G

    2015-09-01

    The reuse of data captured during health care delivery is essential to satisfy the demands of clinical research and clinical decision support systems. A main barrier for the reuse is the existence of legacy formats of data and the high granularity of it when stored in an electronic health record (EHR) system. Thus, we need mechanisms to standardize, aggregate, and query data concealed in the EHRs, to allow their reuse whenever they are needed. To create a data warehouse infrastructure using archetype-based technologies, standards and query languages to enable the interoperability needed for data reuse. The work presented makes use of best of breed archetype-based data transformation and storage technologies to create a workflow for the modeling, extraction, transformation and load of EHR proprietary data into standardized data repositories. We converted legacy data and performed patient-centered aggregations via archetype-based transformations. Later, specific purpose aggregations were performed at a query level for particular use cases. Laboratory test results of a population of 230,000 patients belonging to Troms and Finnmark counties in Norway requested between January 2013 and November 2014 have been standardized. Test records normalization has been performed by defining transformation and aggregation functions between the laboratory records and an archetype. These mappings were used to automatically generate open EHR compliant data. These data were loaded into an archetype-based data warehouse. Once loaded, we defined indicators linked to the data in the warehouse to monitor test activity of Salmonella and Pertussis using the archetype query language. Archetype-based standards and technologies can be used to create a data warehouse environment that enables data from EHR systems to be reused in clinical research and decision support systems. With this approach, existing EHR data becomes available in a standardized and interoperable format, thus opening a world

  10. Designing ETL Tools to Feed a Data Warehouse Based on Electronic Healthcare Record Infrastructure.

    Science.gov (United States)

    Pecoraro, Fabrizio; Luzi, Daniela; Ricci, Fabrizio L

    2015-01-01

    Aim of this paper is to propose a methodology to design Extract, Transform and Load (ETL) tools in a clinical data warehouse architecture based on the Electronic Healthcare Record (EHR). This approach takes advantages on the use of this infrastructure as one of the main source of information to feed the data warehouse, taking also into account that clinical documents produced by heterogeneous legacy systems are structured using the HL7 CDA standard. This paper describes the main activities to be performed to map the information collected in the different types of document with the dimensional model primitives.

  11. Using electron irradiation to probe iron-based superconductors

    Science.gov (United States)

    Cho, Kyuil; Kończykowski, M.; Teknowijoyo, S.; Tanatar, M. A.; Prozorov, R.

    2018-06-01

    High-energy electron irradiation at low temperatures is an efficient and controlled way to create vacancy–interstitial Frenkel pairs in a crystal lattice, thereby inducing nonmagnetic point-like scattering centers. In combination with London penetration depth and resistivity measurements, the electron irradiation was used as a phase-sensitive probe to study the superconducting order parameter in iron-based superconductors (FeSCs), lending strong support to sign-changing s ± pairing. Here, we review the key results of the effect of electron irradiation in FeSCs.

  12. Lifelong Learning from Natural Disasters: Transformative Group-Based Learning at Philippine Universities

    Science.gov (United States)

    Dahl, Kari Kragh Blume; Millora, Christopher Malagad

    2016-01-01

    This study explores reflective experience during transformative, group-based learning among university leaders following a natural disaster such as a typhoon in two Philippine universities. Natural disasters are recurrent phenomena in many parts of the world, but the literature largely ignores their impact on lifelong human learning, for instance…

  13. Sports Coach as Transformative Leader: Arresting School Disengagement through Community Sport-Based Initiatives

    Science.gov (United States)

    Morgan, Haydn J.; Bush, Anthony J.

    2016-01-01

    Reducing social exclusion through interventions designed to sustain school engagement is a key aim of the education and social policy of any government. This paper is a response to the call for there to be more focused empirical sports coaching research through examining the transformative potential of community-based sports coaches to support…

  14. Towards a Strength-Based Juvenile Correctional Facility: Sustainability and Effects of an Institutional Transformation

    Science.gov (United States)

    Barton, William H.; Mackin, Juliette R.

    2012-01-01

    In 2006, the administration of a state-run, secure juvenile correctional facility initiated an attempt to transform its institutional culture using a strength-based approach to assessment and case planning. This resulted in a rapid improvement in institutional climate. The current study revisits this setting several years later to see if those…

  15. A Transformational Approach to VHDL and CDFG Based High-Level Synthesis: a Case Study

    NARCIS (Netherlands)

    Middelhoek, Peter F.A.; Middelhoek, P.F.A.; Mekenkamp, G.E.; Molenkamp, Egbert; Krol, Th.

    1995-01-01

    In this paper, a novel multi-target design methodology based on the concepts of transformational design, and its application to the interlaced-to-progressive scan conversion (IPSC) problem, are discussed. Starting from a single high-level behavioral specification in VHDL a direction detector used in

  16. Pre-processing data using wavelet transform and PCA based on ...

    Indian Academy of Sciences (India)

    Abazar Solgi

    2017-07-14

    Jul 14, 2017 ... Pre-processing data using wavelet transform and PCA based on support vector regression and gene expression programming for river flow simulation. Abazar Solgi1,*, Amir Pourhaghi1, Ramin Bahmani2 and Heidar Zarei3. 1. Department of Water Resources Engineering, Shahid Chamran University of ...

  17. Mechanism of Process-Induced Salt-to-Free Base Transformation of Pharmaceutical Products

    DEFF Research Database (Denmark)

    Bruun Hansen, Thomas; Qu, Haiyan

    2014-01-01

    pH-solubility profiles of a model drug in salt form was established and the mechanism of salt-to-free base form transformation was investigated by increasing pH of the system. Wet massing experiments along with suspension experiments were used to investigate the effects of excipients on the stabi...

  18. Secure electronic commerce communication system based on CA

    Science.gov (United States)

    Chen, Deyun; Zhang, Junfeng; Pei, Shujun

    2001-07-01

    In this paper, we introduce the situation of electronic commercial security, then we analyze the working process and security for SSL protocol. At last, we propose a secure electronic commerce communication system based on CA. The system provide secure services such as encryption, integer, peer authentication and non-repudiation for application layer communication software of browser clients' and web server. The system can implement automatic allocation and united management of key through setting up the CA in the network.

  19. RFID-based Electronic Identity Security Cloud Platform in Cyberspace

    OpenAIRE

    Bing Chen; Chengxiang Tan; Bo Jin; Xiang Zou; Yuebo Dai

    2012-01-01

    With the moving development of networks, especially Internet of Things, electronic identity administration in cyberspace is becoming more and more important. And personal identity management in cyberspace associated with individuals in reality has been one significant and urgent task for the further development of information construction in China. So this paper presents a RFID-based electronic identity security cloud platform in cyberspace to implement an efficient security management of cyb...

  20. A correlative approach to segmenting phases and ferrite morphologies in transformation-induced plasticity steel using electron back-scattering diffraction and energy dispersive X-ray spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Gazder, Azdiar A., E-mail: azdiar@uow.edu.au [Electron Microscopy Centre, University of Wollongong, New South Wales 2500 (Australia); Al-Harbi, Fayez; Spanke, Hendrik Th. [School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, New South Wales 2522 (Australia); Mitchell, David R.G. [Electron Microscopy Centre, University of Wollongong, New South Wales 2500 (Australia); Pereloma, Elena V. [Electron Microscopy Centre, University of Wollongong, New South Wales 2500 (Australia); School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, New South Wales 2522 (Australia)

    2014-12-15

    Using a combination of electron back-scattering diffraction and energy dispersive X-ray spectroscopy data, a segmentation procedure was developed to comprehensively distinguish austenite, martensite, polygonal ferrite, ferrite in granular bainite and bainitic ferrite laths in a thermo-mechanically processed low-Si, high-Al transformation-induced plasticity steel. The efficacy of the ferrite morphologies segmentation procedure was verified by transmission electron microscopy. The variation in carbon content between the ferrite in granular bainite and bainitic ferrite laths was explained on the basis of carbon partitioning during their growth. - Highlights: • Multi-condition segmentation of austenite, martensite, polygonal ferrite and ferrite in bainite. • Ferrites in granular bainite and bainitic ferrite segmented by variation in relative carbon counts. • Carbon partitioning during growth explains variation in carbon content of ferrites in bainites. • Developed EBSD image processing tools can be applied to the microstructures of a variety of alloys. • EBSD-based segmentation procedure verified by correlative TEM results.

  1. A polarized digital shearing speckle pattern interferometry system based on temporal wavelet transformation.

    Science.gov (United States)

    Feng, Ziang; Gao, Zhan; Zhang, Xiaoqiong; Wang, Shengjia; Yang, Dong; Yuan, Hao; Qin, Jie

    2015-09-01

    Digital shearing speckle pattern interferometry (DSSPI) has been recognized as a practical tool in testing strain. The DSSPI system which is based on temporal analysis is attractive because of its ability to measure strain dynamically. In this paper, such a DSSPI system with Wollaston prism has been built. The principles and system arrangement are described and the preliminary experimental result of the displacement-derivative test of an aluminum plate is shown with the wavelet transformation method and the Fourier transformation method. The simulations have been conducted with the finite element method. The comparison of the results shows that quantitative measurement of displacement-derivative has been realized.

  2. Optimizing efficiency on conventional transformer based low power AC/DC standby power supplies

    DEFF Research Database (Denmark)

    Nielsen, Nils

    2004-01-01

    This article describes the research results for simple and cheap methods to reduce the idle- and load-losses in very low power conventional transformer based power supplies intended for standby usage. In this case "very low power" means 50 Hz/230 V-AC to 5 V-DC@1 W. The efficiency is measured...... on two common power supply topologies designed for this power level. The two described topologies uses either a series (or linear) or a buck regulation approach. Common to the test power supplies is they either are using a standard cheap off-the-shelf transformer, or one, which are loss optimized by very...

  3. Dynamic optimum dead time in piezoelectric transformer-based switch-mode power supplies

    DEFF Research Database (Denmark)

    Ekhtiari, Marzieh; Andersen, Thomas; Andersen, Michael A. E.

    2016-01-01

    to charge and discharge the input capacitance of piezoelectric transformers in order to achieve zero-voltage switching. This paper proposes a method for detecting the optimum dead time in piezoelectric transformer-based switch-mode power supplies. The provision of sufficient dead time in every cycle......Soft switching is required to attain high efficiency in high-frequency power converters. Piezoelectric transformerbased converters can benefit from soft switching in terms of significantly diminished switching losses and stresses. Adequate dead time is needed in order to deliver sufficient energy...

  4. Managing the PSTN transformation a blueprint for a successful migration to IP-based networks

    CERN Document Server

    Dornheim, Sandra

    2015-01-01

    While there are many scholarly books and papers that cover the technical issues behind the public switched telephone network (PSTN) migration, few books describe exactly how to manage the migration process economically. Filling this need, Managing the PSTN Transformation: A Blueprint for a Successful Migration to IP-Based Networks reflects the latest understanding of the challenges behind migrating customers from the old PSTN network to an IP infrastructure. The IP transformation blueprint described in this book is not a theoretical cookbook that describes how this could work. Instead, the boo

  5. Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics Individualized Learning System. CANTRAC A-100-0010. Module Ten: Transformers. Study Booklet.

    Science.gov (United States)

    Chief of Naval Education and Training Support, Pensacola, FL.

    This individualized learning module on transformers is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian setting. Six lessons are included in the module:…

  6. Phase Transformation and Lithiation Effect on Electronic Structure of LixFePO4 : An In-Depth Study by Soft X-ray and Simulations

    NARCIS (Netherlands)

    Liu, Xiaosong; Liu, Jun; Qiao, Ruimin; Yu, Yan; Li, Hong; Suo, Liumin; Hu, Yong-sheng; Chuang, Yi-De; Shu, Guojiun; Chou, Fangcheng; Weng, Tsu-Chien; Nordlund, Dennis; Sokaras, Dimosthenis; Wang, Yung Jui; Lin, Hsin; Barbiellini, Bernardo; Bansil, Arun; Song, Xiangyun; Liu, Zhi; Yan, Shishen; Liu, Gao; Qjao, Shan; Richardson, Thomas J.; Prendergast, David; Hussain, Zahid; de Groot, Frank M. F.|info:eu-repo/dai/nl/08747610X; Yang, Wanli

    2012-01-01

    Through soft X-ray absorption spectroscopy, hard X-ray Raman scattering, and theoretical simulations, we provide the most in-depth and systematic study of the phase transformation and (de)lithiation effect on electronic structure in LixFePO4 nanoparticles and single crystals. Soft X-ray reveals

  7. The effect of mutations on the structure of insulin fibrils studied by Fourier transform infrared (FTIR) spectroscopy and electron microscopy.

    Science.gov (United States)

    Garriques, Liza Nielsen; Frokjaer, Sven; Carpenter, John F; Brange, Jens

    2002-12-01

    Fibril formation (aggregation) of human and bovine insulin and six human insulin mutants in hydrochloric acid were investigated by visual inspection, Thioflavin T fluorescence spectroscopy, transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy. The fibrillation tendencies of the wild-type insulins and the insulin mutants were (in order of decreasing fibrillation tendencies): Glu(B1) + Glu(B27) = bovine < human < des-(B1,B2)-insulin < Ser(B2) + Asp(B10) < Glu(A13) + Glu(B10) = Gln(B17) < Asp(B10). Transmission electron micrographs showed that the protofibrils of the mutants were similar to those of wild-type insulins and had a diameter of 5-10 nm and lengths varying from 50 nm to several microns. The fibrils of human insulin mutants exhibited varying degrees of lateral aggregation. The Asp(B10) mutant and human insulin had greater tendency to form laterally aggregated fibrils arranged in parallel bundles, whereas fibrils of the other mutants and bovine insulin were mainly arranged in helical filaments. FTIR spectroscopy showed that the native secondary structure of the wild-type insulins and the human insulin mutants in hydrochloric acid were identical, whereas the secondary structure of the fibrils formed by heating at 50 degrees C depended on the amino acid substitution. FTIR spectra of fibrils of the human insulin mutants exhibited different beta-sheet bands at 1,620-1,640 cm(-1), indicating that the beta-sheet interactions in the fibrils depended on variations in the primary structure of insulin. Copyright 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:2473-2480, 2002

  8. The backward phase flow and FBI-transform-based Eulerian Gaussian beams for the Schroedinger equation

    International Nuclear Information System (INIS)

    Leung Shingyu; Qian Jianliang

    2010-01-01

    We propose the backward phase flow method to implement the Fourier-Bros-Iagolnitzer (FBI)-transform-based Eulerian Gaussian beam method for solving the Schroedinger equation in the semi-classical regime. The idea of Eulerian Gaussian beams has been first proposed in . In this paper we aim at two crucial computational issues of the Eulerian Gaussian beam method: how to carry out long-time beam propagation and how to compute beam ingredients rapidly in phase space. By virtue of the FBI transform, we address the first issue by introducing the reinitialization strategy into the Eulerian Gaussian beam framework. Essentially we reinitialize beam propagation by applying the FBI transform to wavefields at intermediate time steps when the beams become too wide. To address the second issue, inspired by the original phase flow method, we propose the backward phase flow method which allows us to compute beam ingredients rapidly. Numerical examples demonstrate the efficiency and accuracy of the proposed algorithms.

  9. A gravitational wave burst search method based on the S transform

    International Nuclear Information System (INIS)

    Clapson, Andre-Claude; Barsuglia, Matteo; Bizouard, Marie-Anne; Brisson, Violette; Cavalier, Fabien; Davier, Michel; Hello, Patrice; Kreckelberg, Stephane; Varvella, Monica

    2005-01-01

    The detection of burst-type events in the output of ground gravitational wave observatories is particularly challenging due to the expected variety of astrophysical waveforms and the issue of discriminating them from instrumental noise. Robust methods, that achieve reasonable detection performances over a wide range of signals, would be most useful. We present a burst-detection pipeline based on a time-frequency transform, the S transform. This transform offers good time-frequency localization of energy without requiring prior knowledge of the event structure. We set a simple (and robust) event extraction chain. Results are provided for a variety of signals injected in simulated Gaussian statistics data (from the LIGO-Virgo joint working group). Indications are that detection is robust with respect to event type and that efficiency compares reasonably with reference methods. The time-frequency representation is shown to be affected by spectral features such as resonant lines. This emphasizes the role of pre-processing

  10. [Affine transformation-based automatic registration for peripheral digital subtraction angiography (DSA)].

    Science.gov (United States)

    Kong, Gang; Dai, Dao-Qing; Zou, Lu-Min

    2008-07-01

    In order to remove the artifacts of peripheral digital subtraction angiography (DSA), an affine transformation-based automatic image registration algorithm is introduced here. The whole process is described as follows: First, rectangle feature templates are constructed with their centers of the extracted Harris corners in the mask, and motion vectors of the central feature points are estimated using template matching technology with the similarity measure of maximum histogram energy. And then the optimal parameters of the affine transformation are calculated with the matrix singular value decomposition (SVD) method. Finally, bilinear intensity interpolation is taken to the mask according to the specific affine transformation. More than 30 peripheral DSA registrations are performed with the presented algorithm, and as the result, moving artifacts of the images are removed with sub-pixel precision, and the time consumption is less enough to satisfy the clinical requirements. Experimental results show the efficiency and robustness of the algorithm.

  11. Digitized self-oscillating loop for piezoelectric transformer-based power converters

    DEFF Research Database (Denmark)

    Ekhtiari, Marzieh; Andersen, Thomas; Zhang, Zhe

    2016-01-01

    A new method is implemented in designing of self-oscillating loop for driving piezoelectric transformers. The implemented method is based on combining both analog and digital control systems. Digitized delay, or digitized phase shift through the self-oscillating loop results in a very precise...... frequency control and ensures an optimum operation of the piezoelectric transformer in terms of voltage gain and efficiency. In this work, additional time delay is implemented digitally for the first time through 16 bit digital-to-analog converter to the self-oscillating loop. Delay control setpoints...... updates at a rate of 417 kHz. This allows the control loop to dynamically follow frequency changes of the transformer in each resonant cycle. The operation principle behind self-oscillating is discussed in this paper. Moreover, experimental results are reported....

  12. Implementation of Texture Based Image Retrieval Using M-band Wavelet Transform

    Institute of Scientific and Technical Information of China (English)

    LiaoYa-li; Yangyan; CaoYang

    2003-01-01

    Wavelet transform has attracted attention because it is a very useful tool for signal analyzing. As a fundamental characteristic of an image, texture traits play an important role in the human vision system for recognition and interpretation of images. The paper presents an approach to implement texture-based image retrieval using M-band wavelet transform. Firstly the traditional 2-band wavelet is extended to M-band wavelet transform. Then the wavelet moments are computed by M-band wavelet coefficients in the wavelet domain. The set of wavelet moments forms the feature vector related to the texture distribution of each wavelet images. The distances between the feature vectors describe the similarities of different images. The experimental result shows that the M-band wavelet moment features of the images are effective for image indexing.The retrieval method has lower computational complexity, yet it is capable of giving better retrieval performance for a given medical image database.

  13. Optimum phase shift in the self-oscillating loop for piezoelectric transformer-based power converters

    DEFF Research Database (Denmark)

    Ekhtiari, Marzieh; Zsurzsan, Tiberiu-Gabriel; Andersen, Michael A. E.

    2017-01-01

    A new method is implemented in designing of self-oscillating loop for driving piezoelectric transformers. The implemented method is based on combining both analog and digital control systems. Digitally controlled time delay through the self-oscillating loop results in very precise frequency control...... and ensures optimum operation of the piezoelectric transformer in terms of gain and efficiency. Time delay is implemented digitally for the first time through a 16 bit digital-to-analog converter in the self-oscillating loop. The new design of the delay circuit provides 45 ps time resolution, enabling fine......-grained control of phase in the self-oscillating loop. This allows the control loop to dynamically follow frequency changes of the transformer in each resonant cycle. Ultimately, by selecting the optimum phase shift, maximum efficiency under the load and temperature condition is achievable....

  14. A gravitational wave burst search method based on the S transform

    Energy Technology Data Exchange (ETDEWEB)

    Clapson, Andre-Claude; Barsuglia, Matteo; Bizouard, Marie-Anne; Brisson, Violette; Cavalier, Fabien; Davier, Michel; Hello, Patrice; Kreckelberg, Stephane; Varvella, Monica [Groupe Virgo, LAL, Universite Paris-Sud, Batiment 208, BP 34, F-91898 Orsay Cedex (France)

    2005-09-21

    The detection of burst-type events in the output of ground gravitational wave observatories is particularly challenging due to the expected variety of astrophysical waveforms and the issue of discriminating them from instrumental noise. Robust methods, that achieve reasonable detection performances over a wide range of signals, would be most useful. We present a burst-detection pipeline based on a time-frequency transform, the S transform. This transform offers good time-frequency localization of energy without requiring prior knowledge of the event structure. We set a simple (and robust) event extraction chain. Results are provided for a variety of signals injected in simulated Gaussian statistics data (from the LIGO-Virgo joint working group). Indications are that detection is robust with respect to event type and that efficiency compares reasonably with reference methods. The time-frequency representation is shown to be affected by spectral features such as resonant lines. This emphasizes the role of pre-processing.

  15. Improvement of burst-mode control of piezoelectric transformer based DC/DC converter

    International Nuclear Information System (INIS)

    Vasic, Dejan; Liu, Yuan-Ping; Costa, François; Schwander, Denis; Wu, Wen-Jong

    2013-01-01

    Burst-mode operation is adopted sometimes in piezoelectric transformer based converters for two major purposes: (1) to achieve voltage regulation in DC/DC converters and (2) to achieve dimming control in backlight inverters. Burst-mode control enables the converter to operate at a constant switching frequency as well as to maintain good efficiency at light load conditions. However, in practice, the piezoelectric transformer cannot instantly stop vibrating in the burst-mode due to its high quality factor. The delay in the output voltage change resulting from this behavior influences the accuracy of the regulation. This paper proposes a control strategy to make the piezoelectric transformer stop more quickly so as to enhance the accuracy of burst-mode control. The proposed method only modifies the control signal of the burst-mode driving circuit. The proposed control strategy is verified by experiments in a step-down 9 W DC/DC converter. (paper)

  16. A New Approach to High-accuracy Road Orthophoto Mapping Based on Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Ming Yang

    2011-12-01

    Full Text Available Existing orthophoto map based on satellite photography and aerial photography is not precise enough for road marking. This paper proposes a new approach to high-accuracy orthophoto mapping. The approach uses inverse perspective transformation to process the image information and generates the orthophoto fragment. The offline interpolation algorithm is used to process the location information. It processes the dead reckoning and the EKF location information, and uses the result to transform the fragments to the global coordinate system. At last it uses wavelet transform to divides the image to two frequency bands and uses weighted median algorithm to deal with them separately. The result of experiment shows that the map produced with this method has high accuracy.

  17. A compact high-voltage pulse generator based on pulse transformer with closed magnetic core.

    Science.gov (United States)

    Zhang, Yu; Liu, Jinliang; Cheng, Xinbing; Bai, Guoqiang; Zhang, Hongbo; Feng, Jiahuai; Liang, Bo

    2010-03-01

    A compact high-voltage nanosecond pulse generator, based on a pulse transformer with a closed magnetic core, is presented in this paper. The pulse generator consists of a miniaturized pulse transformer, a curled parallel strip pulse forming line (PFL), a spark gap, and a matched load. The innovative design is characterized by the compact structure of the transformer and the curled strip PFL. A new structure of transformer windings was designed to keep good insulation and decrease distributed capacitance between turns of windings. A three-copper-strip structure was adopted to avoid asymmetric coupling of the curled strip PFL. When the 31 microF primary capacitor is charged to 2 kV, the pulse transformer can charge the PFL to 165 kV, and the 3.5 ohm matched load can deliver a high-voltage pulse with a duration of 9 ns, amplitude of 84 kV, and rise time of 5.1 ns. When the load is changed to 50 ohms, the output peak voltage of the generator can be 165 kV, the full width at half maximum is 68 ns, and the rise time is 6.5 ns.

  18. 2D co-ordinate transformation based on a spike timing-dependent plasticity learning mechanism.

    Science.gov (United States)

    Wu, QingXiang; McGinnity, Thomas Martin; Maguire, Liam; Belatreche, Ammar; Glackin, Brendan

    2008-11-01

    In order to plan accurate motor actions, the brain needs to build an integrated spatial representation associated with visual stimuli and haptic stimuli. Since visual stimuli are represented in retina-centered co-ordinates and haptic stimuli are represented in body-centered co-ordinates, co-ordinate transformations must occur between the retina-centered co-ordinates and body-centered co-ordinates. A spiking neural network (SNN) model, which is trained with spike-timing-dependent-plasticity (STDP), is proposed to perform a 2D co-ordinate transformation of the polar representation of an arm position to a Cartesian representation, to create a virtual image map of a haptic input. Through the visual pathway, a position signal corresponding to the haptic input is used to train the SNN with STDP synapses such that after learning the SNN can perform the co-ordinate transformation to generate a representation of the haptic input with the same co-ordinates as a visual image. The model can be applied to explain co-ordinate transformation in spiking neuron based systems. The principle can be used in artificial intelligent systems to process complex co-ordinate transformations represented by biological stimuli.

  19. Analysis of Vector Quantizers Using Transformed Codebooks with Application to Feedback-Based Multiple Antenna Systems

    Directory of Open Access Journals (Sweden)

    Bhaskar D. Rao

    2008-07-01

    Full Text Available Transformed codebooks are obtained by a transformation of a given codebook to best match the statistical environment at hand. The procedure, though suboptimal, has recently been suggested for feedback of channel state information (CSI in multiple antenna systems with correlated channels because of their simplicity and effectiveness. In this paper, we first consider the general distortion analysis of vector quantizers with transformed codebooks. Bounds on the average system distortion of this class of quantizers are provided. It exposes the effects of two kinds of suboptimality introduced by the transformed codebook, namely, the loss caused by suboptimal point density and the loss caused by mismatched Voronoi shape. We then focus our attention on the application of the proposed general framework to providing capacity analysis of a feedback-based MISO system over spatially correlated fading channels. In particular, with capacity loss as an objective function, upper and lower bounds on the average distortion of MISO systems with transformed codebooks are provided and compared to that of the optimal channel quantizers. The expressions are examined to provide interesting insights in the high and low SNR regime. Numerical and simulation results are presented which confirm the tightness of the distortion bounds.

  20. Retinal Identification Based on an Improved Circular Gabor Filter and Scale Invariant Feature Transform

    Directory of Open Access Journals (Sweden)

    Xiaoming Xi

    2013-07-01

    Full Text Available Retinal identification based on retinal vasculatures in the retina provides the most secure and accurate means of authentication among biometrics and has primarily been used in combination with access control systems at high security facilities. Recently, there has been much interest in retina identification. As digital retina images always suffer from deformations, the Scale Invariant Feature Transform (SIFT, which is known for its distinctiveness and invariance for scale and rotation, has been introduced to retinal based identification. However, some shortcomings like the difficulty of feature extraction and mismatching exist in SIFT-based identification. To solve these problems, a novel preprocessing method based on the Improved Circular Gabor Transform (ICGF is proposed. After further processing by the iterated spatial anisotropic smooth method, the number of uninformative SIFT keypoints is decreased dramatically. Tested on the VARIA and eight simulated retina databases combining rotation and scaling, the developed method presents promising results and shows robustness to rotations and scale changes.

  1. Path Index Based Keywords to SPARQL Query Transformation for Semantic Data Federations

    Directory of Open Access Journals (Sweden)

    Thilini Cooray

    2016-06-01

    Full Text Available Semantic web is a highly emerging research domain. Enhancing the ability of keyword query processing on Semantic Web data provides a huge support for familiarizing the usefulness of Semantic Web to the general public. Most of the existing approaches focus on just user keyword matching to RDF graphs and output the connecting elements as results. Semantic Web consists of SPARQL query language which can process queries more accurately and efficiently than general keyword matching. There are only about a couple of approaches available for transforming keyword queries to SPARQL. They basically rely on real time graph traversals? for identifying subgraphs which can connect user keywords. Those approaches are either limited to query processing on a single data store or a set of interlinked data sets. They have not focused on query processing on a federation of independent data sets which belongs to the same domain. This research proposes a Path Index based approach eliminating real time graph traversal for transforming keyword queries to SPARQL. We have introduced an ontology alignment based approach for keyword query transforming on a federation of RDF data stored using multiple heterogeneous vocabularies. Evaluation shows that the proposed approach have the ability to generate SPARQL queries which can provide highly relevant results for user keyword queries. The Path Index based query transformation approach has also achieved high efficiency compared to the existing approach.

  2. Discrete Multiwavelet Critical-Sampling Transform-Based OFDM System over Rayleigh Fading Channels

    Directory of Open Access Journals (Sweden)

    Sameer A. Dawood

    2015-01-01

    Full Text Available Discrete multiwavelet critical-sampling transform (DMWCST has been proposed instead of fast Fourier transform (FFT in the realization of the orthogonal frequency division multiplexing (OFDM system. The proposed structure further reduces the level of interference and improves the bandwidth efficiency through the elimination of the cyclic prefix due to the good orthogonality and time-frequency localization properties of the multiwavelet transform. The proposed system was simulated using MATLAB to allow various parameters of the system to be varied and tested. The performance of DMWCST-based OFDM (DMWCST-OFDM was compared with that of the discrete wavelet transform-based OFDM (DWT-OFDM and the traditional FFT-based OFDM (FFT-OFDM over flat fading and frequency-selective fading channels. Results obtained indicate that the performance of the proposed DMWCST-OFDM system achieves significant improvement compared to those of DWT-OFDM and FFT-OFDM systems. DMWCST improves the performance of the OFDM system by a factor of 1.5–2.5 dB and 13–15.5 dB compared with the DWT and FFT, respectively. Therefore the proposed system offers higher data rate in wireless mobile communications.

  3. Thiazole-based organic semiconductors for organic electronics.

    Science.gov (United States)

    Lin, Yuze; Fan, Haijun; Li, Yongfang; Zhan, Xiaowei

    2012-06-19

    Over the past two decades, organic semiconductors have been the subject of intensive academic and commercial interests. Thiazole is a common electron-accepting heterocycle due to electron-withdrawing nitrogen of imine (C=N), several moieties based on thiazole have been widely introduced into organic semiconductors, and yielded high performance in organic electronic devices. This article reviews recent developments in the area of thiazole-based organic semiconductors, particularly thiazole, bithiazole, thiazolothiazole and benzobisthiazole-based small molecules and polymers, for applications in organic field-effect transistors, solar cells and light-emitting diodes. The remaining problems and challenges, and the key research direction in near future are discussed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Semiconductor-based, large-area, flexible, electronic devices

    Science.gov (United States)

    Goyal, Amit [Knoxville, TN

    2011-03-15

    Novel articles and methods to fabricate the same resulting in flexible, large-area, triaxially textured, single-crystal or single-crystal-like, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  5. Improved medical image fusion based on cascaded PCA and shift invariant wavelet transforms.

    Science.gov (United States)

    Reena Benjamin, J; Jayasree, T

    2018-02-01

    In the medical field, radiologists need more informative and high-quality medical images to diagnose diseases. Image fusion plays a vital role in the field of biomedical image analysis. It aims to integrate the complementary information from multimodal images, producing a new composite image which is expected to be more informative for visual perception than any of the individual input images. The main objective of this paper is to improve the information, to preserve the edges and to enhance the quality of the fused image using cascaded principal component analysis (PCA) and shift invariant wavelet transforms. A novel image fusion technique based on cascaded PCA and shift invariant wavelet transforms is proposed in this paper. PCA in spatial domain extracts relevant information from the large dataset based on eigenvalue decomposition, and the wavelet transform operating in the complex domain with shift invariant properties brings out more directional and phase details of the image. The significance of maximum fusion rule applied in dual-tree complex wavelet transform domain enhances the average information and morphological details. The input images of the human brain of two different modalities (MRI and CT) are collected from whole brain atlas data distributed by Harvard University. Both MRI and CT images are fused using cascaded PCA and shift invariant wavelet transform method. The proposed method is evaluated based on three main key factors, namely structure preservation, edge preservation, contrast preservation. The experimental results and comparison with other existing fusion methods show the superior performance of the proposed image fusion framework in terms of visual and quantitative evaluations. In this paper, a complex wavelet-based image fusion has been discussed. The experimental results demonstrate that the proposed method enhances the directional features as well as fine edge details. Also, it reduces the redundant details, artifacts, distortions.

  6. Grid-based electronic structure calculations: The tensor decomposition approach

    Energy Technology Data Exchange (ETDEWEB)

    Rakhuba, M.V., E-mail: rakhuba.m@gmail.com [Skolkovo Institute of Science and Technology, Novaya St. 100, 143025 Skolkovo, Moscow Region (Russian Federation); Oseledets, I.V., E-mail: i.oseledets@skoltech.ru [Skolkovo Institute of Science and Technology, Novaya St. 100, 143025 Skolkovo, Moscow Region (Russian Federation); Institute of Numerical Mathematics, Russian Academy of Sciences, Gubkina St. 8, 119333 Moscow (Russian Federation)

    2016-05-01

    We present a fully grid-based approach for solving Hartree–Fock and all-electron Kohn–Sham equations based on low-rank approximation of three-dimensional electron orbitals. Due to the low-rank structure the total complexity of the algorithm depends linearly with respect to the one-dimensional grid size. Linear complexity allows for the usage of fine grids, e.g. 8192{sup 3} and, thus, cheap extrapolation procedure. We test the proposed approach on closed-shell atoms up to the argon, several molecules and clusters of hydrogen atoms. All tests show systematical convergence with the required accuracy.

  7. Electronic states of emodin and its conjugate base

    DEFF Research Database (Denmark)

    Nguyen, Son Chi; Hansen, Bjarke Knud Vilster; Hoffmann, Søren Vrønning

    2008-01-01

    The electronic transitions of emodin (1,3,8-trihydroxy-6-methyl-9,10-anthraquinone, E) and its conjugate base (3-oxido-6-methyl-1,8-dihydroxy-9,10-anthraquinone, Ecb) were investigated by UV-Vis linear dichroism (LD) spectroscopy on molecular samples aligned in stretched poly(vinylalcohol). The e......The electronic transitions of emodin (1,3,8-trihydroxy-6-methyl-9,10-anthraquinone, E) and its conjugate base (3-oxido-6-methyl-1,8-dihydroxy-9,10-anthraquinone, Ecb) were investigated by UV-Vis linear dichroism (LD) spectroscopy on molecular samples aligned in stretched poly...

  8. rf streak camera based ultrafast relativistic electron diffraction.

    Science.gov (United States)

    Musumeci, P; Moody, J T; Scoby, C M; Gutierrez, M S; Tran, T

    2009-01-01

    We theoretically and experimentally investigate the possibility of using a rf streak camera to time resolve in a single shot structural changes at the sub-100 fs time scale via relativistic electron diffraction. We experimentally tested this novel concept at the UCLA Pegasus rf photoinjector. Time-resolved diffraction patterns from thin Al foil are recorded. Averaging over 50 shots is required in order to get statistics sufficient to uncover a variation in time of the diffraction patterns. In the absence of an external pump laser, this is explained as due to the energy chirp on the beam out of the electron gun. With further improvements to the electron source, rf streak camera based ultrafast electron diffraction has the potential to yield truly single shot measurements of ultrafast processes.

  9. Optical characterization of free electron concentration in heteroepitaxial InN layers using Fourier transform infrared spectroscopy and a 2 × 2 transfer-matrix algebra

    International Nuclear Information System (INIS)

    Katsidis, C. C.; Ajagunna, A. O.; Georgakilas, A.

    2013-01-01

    Fourier Transform Infrared (FTIR) reflectance spectroscopy has been implemented as a non-destructive, non-invasive, tool for the optical characterization of a set of c-plane InN single heteroepitaxial layers spanning a wide range of thicknesses (30–2000 nm). The c-plane (0001) InN epilayers were grown by plasma-assisted molecular beam epitaxy (PAMBE) on GaN(0001) buffer layers which had been grown on Al 2 O 3 (0001) substrates. It is shown that for arbitrary multilayers with homogeneous anisotropic layers having their principal axes coincident with the laboratory coordinates, a 2 × 2 matrix algebra based on a general transfer-matrix method (GTMM) is adequate to interpret their optical response. Analysis of optical reflectance in the far and mid infrared spectral range has been found capable to discriminate between the bulk, the surface and interface contributions of free carriers in the InN epilayers revealing the existence of electron accumulation layers with carrier concentrations in mid 10 19 cm −3 at both the InN surface and the InN/GaN interface. The spectra could be fitted with a three-layer model, determining the different electron concentration and mobility values of the bulk and of the surface and the interface electron accumulation layers in the InN films. The variation of these values with increasing InN thickness could be also sensitively detected by the optical measurements. The comparison between the optically determined drift mobility and the Hall mobility of the thickest sample reveals a value of r H = 1.49 for the Hall factor of InN at a carrier concentration of 1.11 × 10 19 cm −3 at 300°Κ.

  10. Electronic Biosensors Based on III-Nitride Semiconductors.

    Science.gov (United States)

    Kirste, Ronny; Rohrbaugh, Nathaniel; Bryan, Isaac; Bryan, Zachary; Collazo, Ramon; Ivanisevic, Albena

    2015-01-01

    We review recent advances of AlGaN/GaN high-electron-mobility transistor (HEMT)-based electronic biosensors. We discuss properties and fabrication of III-nitride-based biosensors. Because of their superior biocompatibility and aqueous stability, GaN-based devices are ready to be implemented as next-generation biosensors. We review surface properties, cleaning, and passivation as well as different pathways toward functionalization, and critically analyze III-nitride-based biosensors demonstrated in the literature, including those detecting DNA, bacteria, cancer antibodies, and toxins. We also discuss the high potential of these biosensors for monitoring living cardiac, fibroblast, and nerve cells. Finally, we report on current developments of covalent chemical functionalization of III-nitride devices. Our review concludes with a short outlook on future challenges and projected implementation directions of GaN-based HEMT biosensors.

  11. A progressive data compression scheme based upon adaptive transform coding: Mixture block coding of natural images

    Science.gov (United States)

    Rost, Martin C.; Sayood, Khalid

    1991-01-01

    A method for efficiently coding natural images using a vector-quantized variable-blocksized transform source coder is presented. The method, mixture block coding (MBC), incorporates variable-rate coding by using a mixture of discrete cosine transform (DCT) source coders. Which coders are selected to code any given image region is made through a threshold driven distortion criterion. In this paper, MBC is used in two different applications. The base method is concerned with single-pass low-rate image data compression. The second is a natural extension of the base method which allows for low-rate progressive transmission (PT). Since the base method adapts easily to progressive coding, it offers the aesthetic advantage of progressive coding without incorporating extensive channel overhead. Image compression rates of approximately 0.5 bit/pel are demonstrated for both monochrome and color images.

  12. Prediction of Dissolved Gas Concentrations in Transformer Oil Based on the KPCA-FFOA-GRNN Model

    Directory of Open Access Journals (Sweden)

    Jun Lin

    2018-01-01

    Full Text Available The purpose of analyzing the dissolved gas in transformer oil is to determine the transformer’s operating status and is an important basis for fault diagnosis. Accurate prediction of the concentration of dissolved gas in oil can provide an important reference for the evaluation of the state of the transformer. A combined predicting model is proposed based on kernel principal component analysis (KPCA and a generalized regression neural network (GRNN using an improved fruit fly optimization algorithm (FFOA to select the smooth factor. Firstly, based on the idea of using the dissolved gas ratio of oil to diagnose the transformer fault, gas concentration ratios are also used as characteristic parameters. Secondly, the main parameters are selected from the feature parameters using the KPCA method, and the GRNN is then used to predict the gas concentration in the transformer oil. In the training process of the network, the FFOA is used to select the smooth factor of the neural network. Through a concrete example, it is shown that the method proposed in this paper has better data fitting ability and more accurate prediction ability compared with the support vector machine (SVM and gray model (GM methods.

  13. Optical-electronic shape recognition system based on synergetic associative memory

    Science.gov (United States)

    Gao, Jun; Bao, Jie; Chen, Dingguo; Yang, Youqing; Yang, Xuedong

    2001-04-01

    This paper presents a novel optical-electronic shape recognition system based on synergetic associative memory. Our shape recognition system is composed of two parts: the first one is feature extraction system; the second is synergetic pattern recognition system. Hough transform is proposed for feature extraction of unrecognized object, with the effects of reducing dimensions and filtering for object distortion and noise, synergetic neural network is proposed for realizing associative memory in order to eliminate spurious states. Then we adopt an approach of optical- electronic realization to our system that can satisfy the demands of real time, high speed and parallelism. In order to realize fast algorithm, we replace the dynamic evolution circuit with adjudge circuit according to the relationship between attention parameters and order parameters, then implement the recognition of some simple images and its validity is proved.

  14. Probabilistic wind power forecasting based on logarithmic transformation and boundary kernel

    International Nuclear Information System (INIS)

    Zhang, Yao; Wang, Jianxue; Luo, Xu

    2015-01-01

    Highlights: • Quantitative information on the uncertainty of wind power generation. • Kernel density estimator provides non-Gaussian predictive distributions. • Logarithmic transformation reduces the skewness of wind power density. • Boundary kernel method eliminates the density leakage near the boundary. - Abstracts: Probabilistic wind power forecasting not only produces the expectation of wind power output, but also gives quantitative information on the associated uncertainty, which is essential for making better decisions about power system and market operations with the increasing penetration of wind power generation. This paper presents a novel kernel density estimator for probabilistic wind power forecasting, addressing two characteristics of wind power which have adverse impacts on the forecast accuracy, namely, the heavily skewed and double-bounded nature of wind power density. Logarithmic transformation is used to reduce the skewness of wind power density, which improves the effectiveness of the kernel density estimator in a transformed scale. Transformations partially relieve the boundary effect problem of the kernel density estimator caused by the double-bounded nature of wind power density. However, the case study shows that there are still some serious problems of density leakage after the transformation. In order to solve this problem in the transformed scale, a boundary kernel method is employed to eliminate the density leak at the bounds of wind power distribution. The improvement of the proposed method over the standard kernel density estimator is demonstrated by short-term probabilistic forecasting results based on the data from an actual wind farm. Then, a detailed comparison is carried out of the proposed method and some existing probabilistic forecasting methods

  15. Principles of water oxidation and O2-based hydrocarbon transformation by multinuclear catalytic sites

    Energy Technology Data Exchange (ETDEWEB)

    Musaev, Djamaladdin G [Chemistry, Emory University; Hill, Craig L [Chemistry, Emory University; Morokuma, Keiji [Chemistry, Emory University

    2014-10-28

    Abstract The central thrust of this integrated experimental and computational research program was to obtain an atomistic-level understanding of the structural and dynamic factors underlying the design of catalysts for water oxidation and selective reductant-free O2-based transformations. The focus was on oxidatively robust polyoxometalate (POM) complexes in which a catalytic active site interacts with proximal metal centers in a synergistic manner. Thirty five publications in high-impact journals arose from this grant. I. Developing an oxidatively and hydrolytically stable and fast water oxidation catalyst (WOC), a central need in the production of green fuels using water as a reductant, has proven particularly challenging. During this grant period we have designed and investigated several carbon-free, molecular (homogenous), oxidatively and hydrolytically stable WOCs, including the Rb8K2[{Ru4O4(OH)2(H2O)4}(γ-SiW10O36)2]·25H2O (1) and [Co4(H2O)2(α-PW9O34)2]10- (2). Although complex 1 is fast, oxidatively and hydrolytically stable WOC, Ru is neither abundant nor inexpensive. Therefore, development of a stable and fast carbon-free homogenous WOC, based on earth-abundant elements became our highest priority. In 2010, we reported the first such catalyst, complex 2. This complex is substantially faster than 1 and stable under homogeneous conditions. Recently, we have extended our efforts and reported a V2-analog of the complex 2, i.e. [Co4(H2O)2(α-VW9O34)2]10- (3), which shows an even greater stability and reactivity. We succeeded in: (a) immobilizing catalysts 1 and 2 on the surface of various electrodes, and (b) elucidating the mechanism of O2 formation and release from complex 1, as well as the Mn4O4L6 “cubane” cluster. We have shown that the direct O-O bond formation is the most likely pathway for O2 formation during water oxidation catalyzed by 1. II. Oxo transfer catalysts that contain two proximal and synergistically interacting redox active metal

  16. Fullerene-based Anchoring Groups for Molecular Electronics

    DEFF Research Database (Denmark)

    Martin, Christian A.; Ding, Dapeng; Sørensen, Jakob Kryger

    2008-01-01

    We present results on a new fullerene-based anchoring group for molecular electronics. Using lithographic mechanically controllable break junctions in vacuum we have determined the conductance and stability of single-molecule junctions of 1,4-bis(fullero[c]pyrrolidin-1-yl)benzene. The compound can...

  17. Electronic and chemical properties of graphene-based structures:

    DEFF Research Database (Denmark)

    Vanin, Marco

    In the present thesis several aspects of graphene-based structures have been investigated using density functional theory calculations to solve the electronic structure problem. A review of the implementation of a localized basis-set within the projector augmented wave method - the way of describ...... are attractive candidates although issues regarding the poisoning of the active site remain to be addressed....

  18. Towards model-based testing of electronic funds transfer systems

    NARCIS (Netherlands)

    Asaadi, H.R.; Khosravi, R.; Mousavi, M.R.; Noroozi, N.; Arbab, F.; Sirjani, M.

    2012-01-01

    We report on our first experience with applying model-based testing techniques to an operational Electronic Funds Transfer (EFT) switch. The goal is to test the conformance of the EFT switch to the standard flows described by the ISO 8583 standard. To this end, we first make a formalization of the

  19. Towards model-based testing of electronic funds transfer systems

    NARCIS (Netherlands)

    Asaadi, H.R.; Khosravi, R.; Mousavi, M.R.; Noroozi, N.

    2010-01-01

    We report on our first experience with applying model-based testing techniques to an operational Electronic Funds Transfer (EFT) switch. The goal is to test the conformance of the EFT switch to the standard flows described by the ISO 8583 standard. To this end, we first make a formalization of the

  20. Towards Evidence-Based Understanding of Electronic Data Sources

    DEFF Research Database (Denmark)

    Chen, Lianping; Ali Babar, Muhammad; Zhang, He

    2010-01-01

    Identifying relevant papers from various Electronic Data Sources (EDS) is one of the key activities of conducting these kinds of studies. Hence, the selection of EDS for searching the potentially relevant papers is an important decision, which can affect a study’s coverage of relevant papers...... the two studies and that from literature to provide initial evidence-based heuristics for EDS selection....

  1. In plane optical sensor based on organic electronic devices

    NARCIS (Netherlands)

    Koetse, M.M; Rensing, P.A.; Heck, G.T. van; Sharpe, R.B.A.; Allard, B.A.M.; Wieringa, F.P.; Kruijt, P.G.M.; Meulendijks, N.M.M.; Jansen, H.; Schoo, H.F.M.

    2008-01-01

    Sensors based on organic electronic devices are emerging in a wide range of application areas. Here we present a sensor platform using organic light emitting diodes (OLED) and organic photodiodes (OPD) as active components. By means of lamination and interconnection technology the functional foils

  2. A Transform-Based Feature Extraction Approach for Motor Imagery Tasks Classification

    Science.gov (United States)

    Khorshidtalab, Aida; Mesbah, Mostefa; Salami, Momoh J. E.

    2015-01-01

    In this paper, we present a new motor imagery classification method in the context of electroencephalography (EEG)-based brain–computer interface (BCI). This method uses a signal-dependent orthogonal transform, referred to as linear prediction singular value decomposition (LP-SVD), for feature extraction. The transform defines the mapping as the left singular vectors of the LP coefficient filter impulse response matrix. Using a logistic tree-based model classifier; the extracted features are classified into one of four motor imagery movements. The proposed approach was first benchmarked against two related state-of-the-art feature extraction approaches, namely, discrete cosine transform (DCT) and adaptive autoregressive (AAR)-based methods. By achieving an accuracy of 67.35%, the LP-SVD approach outperformed the other approaches by large margins (25% compared with DCT and 6 % compared with AAR-based methods). To further improve the discriminatory capability of the extracted features and reduce the computational complexity, we enlarged the extracted feature subset by incorporating two extra features, namely, Q- and the Hotelling’s \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$T^{2}$ \\end{document} statistics of the transformed EEG and introduced a new EEG channel selection method. The performance of the EEG classification based on the expanded feature set and channel selection method was compared with that of a number of the state-of-the-art classification methods previously reported with the BCI IIIa competition data set. Our method came second with an average accuracy of 81.38%. PMID:27170898

  3. Multirate-based fast parallel algorithms for 2-D DHT-based real-valued discrete Gabor transform.

    Science.gov (United States)

    Tao, Liang; Kwan, Hon Keung

    2012-07-01

    Novel algorithms for the multirate and fast parallel implementation of the 2-D discrete Hartley transform (DHT)-based real-valued discrete Gabor transform (RDGT) and its inverse transform are presented in this paper. A 2-D multirate-based analysis convolver bank is designed for the 2-D RDGT, and a 2-D multirate-based synthesis convolver bank is designed for the 2-D inverse RDGT. The parallel channels in each of the two convolver banks have a unified structure and can apply the 2-D fast DHT algorithm to speed up their computations. The computational complexity of each parallel channel is low and is independent of the Gabor oversampling rate. All the 2-D RDGT coefficients of an image are computed in parallel during the analysis process and can be reconstructed in parallel during the synthesis process. The computational complexity and time of the proposed parallel algorithms are analyzed and compared with those of the existing fastest algorithms for 2-D discrete Gabor transforms. The results indicate that the proposed algorithms are the fastest, which make them attractive for real-time image processing.

  4. Properties and Structure of In Situ Transformed PAN-Based Carbon Fibers

    Directory of Open Access Journals (Sweden)

    Jingjing Cao

    2018-06-01

    Full Text Available Carbon fibers in situ prepared during the hot-pressed sintering in a vacuum is termed in situ transformed polyacrylonitrile-based (PAN-based carbon fibers, and the fibrous precursors are the pre-oxidized PAN fibers. The properties and structure of in situ transformed PAN-based carbon fibers are investigated by Nano indenter, SEM, TEM, XRD, and Raman. The results showed that the microstructure of the fiber surface layer was compact, while the core was loose, with evenly-appearing microvoids. The elastic modulus and nanohardness of the fiber surface layer (303.87 GPa and 14.82 GPa were much higher than that of the core (16.57 GPa and 1.54 GPa, and its interlayer spacing d002 and crystallinity were about 0.347 nm and 0.97 respectively. It was found that the preferred orientation of the surface carbon layers with ordered carbon atomic arrangement tended to be parallel to the fiber axis, whereas the fiber core in the amorphous region exhibited a random texture and the carbon atomic arrangement was in a disordered state. It indicates that the in situ transformed PAN-based carbon fibers possess significantly turbostratic structure and anisotropy.

  5. All-optical signal processing of OTDM and OFDM signals based on time-domain optical fourier transformation

    DEFF Research Database (Denmark)

    Galili, Michael; Guan, Pengyu; Lillieholm, Mads

    2017-01-01

    In the talk, we will review recent work on optical signal processing based on time lenses. Various applications of optical Fourier transformation for optical communications will be discussed.......In the talk, we will review recent work on optical signal processing based on time lenses. Various applications of optical Fourier transformation for optical communications will be discussed....

  6. MO-G-304-02: Knowledge Based DVH Prediction Using a Geometric Dose Transform

    International Nuclear Information System (INIS)

    Staub, D; Wang, J; Jiang, S

    2015-01-01

    Purpose: To demonstrate a novel method for predicting patient dose-volume histograms (DVHs) using a prior database of optimized radiotherapy treatment plans. Such predicted DVHs could be useful for automating treatment planning. Methods: Our initial demonstration utilized a database of 100 prostate intensity-modulated radiotherapy (IMRT) data-sets. Each data-set contained a CT image with contours of the planning target volume (PTV), rectum, and bladder, the parameters of a clinically approved IMRT plan, and a corresponding simulated dose distribution. We applied a novel geometric transformation to remove the influence of the PTV size, shape, and location on the dose distribution. We termed the transformed distribution the geometrically normalized dose distribution (GNDD). This normalization transform was applied to 80 data-sets randomly selected from the database, and a population GNDD was computed as the average. Next, the population GNDD was mapped onto each of the remaining 20 patient datasets using the reverse of the geometric normalization transform, and predicted DVHs were calculated from the reverse transformed dose distributions (GNDD-DVHs). In addition, a state of the art machine learning based method from the literature was tested for comparison. Results: DVH prediction accuracy was quantified by calculating the relative root mean squared error (rRMSE) on predicted DVHs for the 20 test patients using their known DVHs. For bladder, rectum, and PTV average rRMSEs for the GNDD method were 9.7 ± 4.2%, 13.9 ± 6.0%, and 2.3 ± 0.5% respectively. Prediction results using GNDD were roughly equivalent to that from the machine learning method. Conclusion: We developed a new method for predicting DVH curves from a database of prior patient plans. We demonstrated that our simple approach achieves accuracy comparable to a method using a complicated machine learning based approach

  7. Novel structures for Discrete Hartley Transform based on first-order moments

    Science.gov (United States)

    Xiong, Jun; Zheng, Wenjuan; Wang, Hao; Liu, Jianguo

    2018-03-01

    Discrete Hartley Transform (DHT) is an important tool in digital signal processing. In the present paper, the DHT is firstly transformed into the first-order moments-based form, then a new fast algorithm is proposed to calculate the first-order moments without multiplication. Based on the algorithm theory, the corresponding hardware architecture for DHT is proposed, which only contains shift operations and additions with no need for multipliers and large memory. To verify the availability and effectiveness, the proposed design is implemented with hardware description language and synthesized by Synopsys Design Compiler with 0.18-μm SMIC library. A series of experiments have proved that the proposed architecture has better performance in terms of the product of the hardware consumption and computation time.

  8. An Image Matching Method Based on Fourier and LOG-Polar Transform

    Directory of Open Access Journals (Sweden)

    Zhijia Zhang

    2014-04-01

    Full Text Available This Traditional template matching methods are not appropriate for the situation of large angle rotation between two images in the online detection for industrial production. Aiming at this problem, Fourier transform algorithm was introduced to correct image rotation angle based on its rotatary invariance in time-frequency domain, orienting image under test in the same direction with reference image, and then match these images using matching algorithm based on log-polar transform. Compared with the current matching algorithms, experimental results show that the proposed algorithm can not only match two images with rotation of arbitrary angle, but also possess a high matching accuracy and applicability. In addition, the validity and reliability of algorithm was verified by simulated matching experiment targeting circular images.

  9. Noise Reduction in Breath Sound Files Using Wavelet Transform Based Filter

    Science.gov (United States)

    Syahputra, M. F.; Situmeang, S. I. G.; Rahmat, R. F.; Budiarto, R.

    2017-04-01

    The development of science and technology in the field of healthcare increasingly provides convenience in diagnosing respiratory system problem. Recording the breath sounds is one example of these developments. Breath sounds are recorded using a digital stethoscope, and then stored in a file with sound format. This breath sounds will be analyzed by health practitioners to diagnose the symptoms of disease or illness. However, the breath sounds is not free from interference signals. Therefore, noise filter or signal interference reduction system is required so that breath sounds component which contains information signal can be clarified. In this study, we designed a filter called a wavelet transform based filter. The filter that is designed in this study is using Daubechies wavelet with four wavelet transform coefficients. Based on the testing of the ten types of breath sounds data, the data is obtained in the largest SNRdB bronchial for 74.3685 decibels.

  10. Low-Complexity Multiple Description Coding of Video Based on 3D Block Transforms

    Directory of Open Access Journals (Sweden)

    Andrey Norkin

    2007-02-01

    Full Text Available The paper presents a multiple description (MD video coder based on three-dimensional (3D transforms. Two balanced descriptions are created from a video sequence. In the encoder, video sequence is represented in a form of coarse sequence approximation (shaper included in both descriptions and residual sequence (details which is split between two descriptions. The shaper is obtained by block-wise pruned 3D-DCT. The residual sequence is coded by 3D-DCT or hybrid, LOT+DCT, 3D-transform. The coding scheme is targeted to mobile devices. It has low computational complexity and improved robustness of transmission over unreliable networks. The coder is able to work at very low redundancies. The coding scheme is simple, yet it outperforms some MD coders based on motion-compensated prediction, especially in the low-redundancy region. The margin is up to 3 dB for reconstruction from one description.

  11. FAST DISCRETE CURVELET TRANSFORM BASED ANISOTROPIC FEATURE EXTRACTION FOR IRIS RECOGNITION

    Directory of Open Access Journals (Sweden)

    Amol D. Rahulkar

    2010-11-01

    Full Text Available The feature extraction plays a very important role in iris recognition. Recent researches on multiscale analysis provide good opportunity to extract more accurate information for iris recognition. In this work, a new directional iris texture features based on 2-D Fast Discrete Curvelet Transform (FDCT is proposed. The proposed approach divides the normalized iris image into six sub-images and the curvelet transform is applied independently on each sub-image. The anisotropic feature vector for each sub-image is derived using the directional energies of the curvelet coefficients. These six feature vectors are combined to create the resultant feature vector. During recognition, the nearest neighbor classifier based on Euclidean distance has been used for authentication. The effectiveness of the proposed approach has been tested on two different databases namely UBIRIS and MMU1. Experimental results show the superiority of the proposed approach.

  12. Innovating for Transformation in First Nations Health Using Community-Based Participatory Research.

    Science.gov (United States)

    Kyoon-Achan, Grace; Lavoie, Josée; Avery Kinew, Kathi; Phillips-Beck, Wanda; Ibrahim, Naser; Sinclair, Stephanie; Katz, Alan

    2018-06-01

    Community-based participatory research (CBPR) provides the opportunity to engage communities for sustainable change. We share a journey to transformation in our work with eight Manitoba First Nations seeking to improve the health of their communities and discuss lessons learned. The study used community-based participatory research approach for the conceptualization of the study, data collection, analysis, and knowledge translation. It was accomplished through a variety of methods, including qualitative interviews, administrative health data analyses, surveys, and case studies. Research relationships built on strong ethics and protocols to enhance mutual commitment to support community-driven transformation. Collaborative and respectful relationships are platforms for defining and strengthening community health care priorities. We further discuss how partnerships were forged to own and sustain innovations. This article contributes a blueprint for respectful CBPR. The outcome is a community-owned, widely recognized process that is sustainable while fulfilling researcher and funding obligations.

  13. Phase Transformations in Nickel base Superalloy Inconel 718 during Cyclic Loading at High Temperature

    Directory of Open Access Journals (Sweden)

    Michal Jambor

    2017-06-01

    Full Text Available Nickel base superalloys are hi-tech materials intended for high temperature applications. This property owns a complex microstructure formed by matrix of Ni and variety of precipitates. The type, form and the amount of these phases significantly affect the resulting properties of these alloys. At sufficiently long exposure to high temperatures, the transformation phase can occur, which can lead to degradation of properties of these alloys. A cyclic plastic deformation can accelerate these changes, and they could occur at significantly lower temperatures or in shorter time of exposure. The aim of this study is to describe phase transformation, which can occur by a cyclic plastic deformation at high temperatures in nickel base superalloy Inconel 718.

  14. ORTHOGONAL REPRESENTATION OF THE PROPER TRANSFORMATION OF A PERSYMMETRIC MATRIX BASED ON ROTATION OPERATORS

    Directory of Open Access Journals (Sweden)

    V. M. Demko

    2018-01-01

    Full Text Available The mathematical substantiation of the algorithm for synthesis of the proper transformation and finding the eigenvalue formulae of a persymmetric matrix of dimension N = 2 k ( k =1, 4 based on orthogonal rotation operators is given. The proposed algorithm made it possible to improve the author's approach to calculating eigenvalues based on numerical examples for the maximal dimension of matrices 64×64, resulting the possibility to obtain analytical relations for calculating the eigenvalues of the persymmetric matrix. It is shown that the proper transformation has a factorized structure in the form of a product of rotation operators, each of which is a direct sum of elementary Givens and Jacobian rotation matrices. 

  15. Improved Real-time Denoising Method Based on Lifting Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Liu Zhaohua

    2014-06-01

    Full Text Available Signal denoising can not only enhance the signal to noise ratio (SNR but also reduce the effect of noise. In order to satisfy the requirements of real-time signal denoising, an improved semisoft shrinkage real-time denoising method based on lifting wavelet transform was proposed. The moving data window technology realizes the real-time wavelet denoising, which employs wavelet transform based on lifting scheme to reduce computational complexity. Also hyperbolic threshold function and recursive threshold computing can ensure the dynamic characteristics of the system, in addition, it can improve the real-time calculating efficiency as well. The simulation results show that the semisoft shrinkage real-time denoising method has quite a good performance in comparison to the traditional methods, namely soft-thresholding and hard-thresholding. Therefore, this method can solve more practical engineering problems.

  16. Frequency hopping signal detection based on wavelet decomposition and Hilbert-Huang transform

    Science.gov (United States)

    Zheng, Yang; Chen, Xihao; Zhu, Rui

    2017-07-01

    Frequency hopping (FH) signal is widely adopted by military communications as a kind of low probability interception signal. Therefore, it is very important to research the FH signal detection algorithm. The existing detection algorithm of FH signals based on the time-frequency analysis cannot satisfy the time and frequency resolution requirement at the same time due to the influence of window function. In order to solve this problem, an algorithm based on wavelet decomposition and Hilbert-Huang transform (HHT) was proposed. The proposed algorithm removes the noise of the received signals by wavelet decomposition and detects the FH signals by Hilbert-Huang transform. Simulation results show the proposed algorithm takes into account both the time resolution and the frequency resolution. Correspondingly, the accuracy of FH signals detection can be improved.

  17. Short-term data forecasting based on wavelet transformation and chaos theory

    Science.gov (United States)

    Wang, Yi; Li, Cunbin; Zhang, Liang

    2017-09-01

    A sketch of wavelet transformation and its application was given. Concerning the characteristics of time sequence, Haar wavelet was used to do data reduction. After processing, the effect of “data nail” on forecasting was reduced. Chaos theory was also introduced, a new chaos time series forecasting flow based on wavelet transformation was proposed. The largest Lyapunov exponent was larger than zero from small data sets, it verified the data change behavior still met chaotic behavior. Based on this, chaos time series to forecast short-term change behavior could be used. At last, the example analysis of the price from a real electricity market showed that the forecasting method increased the precision of the forecasting more effectively and steadily.

  18. Alpha-particle detection based on the BJT detector and simple, IC-based readout electronics

    Energy Technology Data Exchange (ETDEWEB)

    Rovati, L; Bonaiuti, M [Dipartimento di Ingegneria dell' Informazione, Universita di Modena e Reggio Emilia, Modena (Italy); Bettarini, S [Dipartimento di Fisica, Universita di Pisa and INFN Pisa, Pisa (Italy); Bosisio, L [Dipartimento di Fisica, Universita di Trieste and INFN Trieste, Trieste (Italy); Dalla Betta, G-F; Tyzhnevyi, V [Dipartimento di Ingegneria e Scienza dell' Informazione, Universita di Trento e INFN Trento, Trento (Italy); Verzellesi, G [Dipartimento di Scienze e Metodi dell' Ingegneria, Universita di Modena e Reggio Emilia and INFN Trento, Reggio Emilia (Italy); Zorzi, N, E-mail: giovanni.verzellesi@unimore.i [Fondazione Bruno Kessler (FBK), Trento (Italy)

    2009-11-15

    In this paper we propose a portable instrument for alpha-particle detection based on a previously-developed BJT detector and a simple, IC-based readout electronics. Experimental tests of the BJT detector and readout electronics are reported. Numerical simulations are adopted to predict the performance enhancement achievable with optimized BJT detectors.

  19. Alpha-particle detection based on the BJT detector and simple, IC-based readout electronics

    International Nuclear Information System (INIS)

    Rovati, L; Bonaiuti, M; Bettarini, S; Bosisio, L; Dalla Betta, G-F; Tyzhnevyi, V; Verzellesi, G; Zorzi, N

    2009-01-01

    In this paper we propose a portable instrument for alpha-particle detection based on a previously-developed BJT detector and a simple, IC-based readout electronics. Experimental tests of the BJT detector and readout electronics are reported. Numerical simulations are adopted to predict the performance enhancement achievable with optimized BJT detectors.

  20. Arikan and Alamouti matrices based on fast block-wise inverse Jacket transform

    Science.gov (United States)

    Lee, Moon Ho; Khan, Md Hashem Ali; Kim, Kyeong Jin

    2013-12-01

    Recently, Lee and Hou (IEEE Signal Process Lett 13: 461-464, 2006) proposed one-dimensional and two-dimensional fast algorithms for block-wise inverse Jacket transforms (BIJTs). Their BIJTs are not real inverse Jacket transforms from mathematical point of view because their inverses do not satisfy the usual condition, i.e., the multiplication of a matrix with its inverse matrix is not equal to the identity matrix. Therefore, we mathematically propose a fast block-wise inverse Jacket transform of orders N = 2 k , 3 k , 5 k , and 6 k , where k is a positive integer. Based on the Kronecker product of the successive lower order Jacket matrices and the basis matrix, the fast algorithms for realizing these transforms are obtained. Due to the simple inverse and fast algorithms of Arikan polar binary and Alamouti multiple-input multiple-output (MIMO) non-binary matrices, which are obtained from BIJTs, they can be applied in areas such as 3GPP physical layer for ultra mobile broadband permutation matrices design, first-order q-ary Reed-Muller code design, diagonal channel design, diagonal subchannel decompose for interference alignment, and 4G MIMO long-term evolution Alamouti precoding design.

  1. Study on New Smart Transformer Terminal Unit Based on ARM and GPRS Network

    Directory of Open Access Journals (Sweden)

    Na Wu

    2013-12-01

    Full Text Available Distribution transformer is one of the most important power equipments in distribution network, whose running state exercises a great influence on the stability of the network. Transformer Terminal Unit (TTU is an effective device to monitor the running state of transformers in the distribution automation system. In this paper, we study a new smart TTU which uses ARM7 series chip as processor, equipped with ATT7022B based electric meter module and GPRS module for remote data transmission control. We focus on the corresponding hardware, software design and the measurement principle of harmonics of TTU. The new TTU can measure the electric parameters of the distribution transformer precisely. Taking advantage of the powerful ARM processor, it can analyze harmonic of the power line effectively. Due to the always-on-line feature of GPRS, TTU can achieve reliable communication with the remote terminal and the master station. Compared with other similar units, the new unit outperforms in terms of real-time, precision and reliability, which can fully meet with the high-speed development of distribution automation system.

  2. A Novel Interference Detection Method of STAP Based on Simplified TT Transform

    Directory of Open Access Journals (Sweden)

    Qiang Wang

    2017-01-01

    Full Text Available Training samples contaminated by target-like signals is one of the major reasons for inhomogeneous clutter environment. In such environment, clutter covariance matrix in STAP (space-time adaptive processing is estimated inaccurately, which finally leads to detection performance reduction. In terms of this problem, a STAP interference detection method based on simplified TT (time-time transform is proposed in this letter. Considering the sparse physical property of clutter in the space-time plane, data on each range cell is first converted into a discrete slow time series. Then, the expression of simplified TT transform about sample data is derived step by step. Thirdly, the energy of each training sample is focalized and extracted by simplified TT transform from energy-variant difference between the unpolluted and polluted stage, and the physical significance of discarding the contaminated samples is analyzed. Lastly, the contaminated samples are picked out in light of the simplified TT transform-spectrum difference. The result on Monte Carlo simulation indicates that when training samples are contaminated by large power target-like signals, the proposed method is more effective in getting rid of the contaminated samples, reduces the computational complexity significantly, and promotes the target detection performance compared with the method of GIP (generalized inner product.

  3. Structure and viscosity of a transformer oil-based ferrofluid under an external electric field

    Energy Technology Data Exchange (ETDEWEB)

    Rajnak, M., E-mail: rajnak@saske.sk [Institute of Experimental Physics SAS, Watsonova 47, 04001 Košice (Slovakia); Faculty of Electrical Engineering and Informatics, Technical University of Košice, Letná 9, 04200 Košice (Slovakia); Timko, M.; Kopcansky, P.; Paulovicova, K. [Institute of Experimental Physics SAS, Watsonova 47, 04001 Košice (Slovakia); Tothova, J.; Kurimsky, J.; Dolnik, B.; Cimbala, R. [Faculty of Electrical Engineering and Informatics, Technical University of Košice, Letná 9, 04200 Košice (Slovakia); Avdeev, M.V. [Joint Institute for Nuclear Research, Joliot-Curie 6, Moscow region, 141980 Dubna (Russian Federation); Petrenko, V.I. [Joint Institute for Nuclear Research, Joliot-Curie 6, Moscow region, 141980 Dubna (Russian Federation); Taras Shevchenko Kyiv National University, Volodymyrska Street 64, 01601 Kyiv (Ukraine); Feoktystov, A. [Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstr. 1, 85748 Garching (Germany)

    2017-06-01

    Various structural changes of ferrofluids have been intensively studied under external magnetic fields. In this work we present an experimental evidence of similar changes induced by an electric field. In the context of the electric field effect on ferrofluids structure, we studied a simple ferrofluid consisting of iron oxide nanoparticles coated with oleic acid and dispersed in transformer oil. The structural changes have been observed both on macroscopic and microscopic scale. We also demonstrate a remarkable impact of the electric field on the ferrofluid viscosity in relation to the reported structural changes. It was found that the electric field induced viscosity changes are analogous to the magnetoviscous effect. These changes and the electroviscous effect are believed to stem from the dielectric permittivity contrast between the iron oxide nanoparticles and transformer oil, giving rise to the effective electric polarization of the nanoparticles. It is highlighted that this electrorheological effect should be considered in studies of ferrofluids for high voltage engineering applications, as it can have impact on the thermomagnetic convection or the dielectric breakdown performance. - Highlights: • An experimental evidence of the electric field induced structural changes in a ferrofluid is presented. • An electroviscous effect in the transformer oil-based ferrofluid is shown. • The dielectric contrast between the particles and the carrier fluid is the key factor. • The potential impact on the thermomagnetic convection of ferrofluids in power transformers is highlighted.

  4. Laplace-transformed atomic orbital-based Møller–Plesset perturbation theory for relativistic two-component Hamiltonians

    Energy Technology Data Exchange (ETDEWEB)

    Helmich-Paris, Benjamin, E-mail: b.helmichparis@vu.nl; Visscher, Lucas, E-mail: l.visscher@vu.nl [Section of Theoretical Chemistry, VU University Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam (Netherlands); Repisky, Michal, E-mail: michal.repisky@uit.no [CTCC, Department of Chemistry, UIT The Arctic University of Norway, N-9037 Tromø (Norway)

    2016-07-07

    We present a formulation of Laplace-transformed atomic orbital-based second-order Møller–Plesset perturbation theory (MP2) energies for two-component Hamiltonians in the Kramers-restricted formalism. This low-order scaling technique can be used to enable correlated relativistic calculations for large molecular systems. We show that the working equations to compute the relativistic MP2 energy differ by merely a change of algebra (quaternion instead of real) from their non-relativistic counterparts. With a proof-of-principle implementation we study the effect of the nuclear charge on the magnitude of half-transformed integrals and show that for light elements spin-free and spin-orbit MP2 energies are almost identical. Furthermore, we investigate the effect of separation of charge distributions on the Coulomb and exchange energy contributions, which show the same long-range decay with the inter-electronic/atomic distance as for non-relativistic MP2. A linearly scaling implementation is possible if the proper distance behavior is introduced to the quaternion Schwarz-type estimates as for non-relativistic MP2.

  5. Laplace-transformed atomic orbital-based Møller–Plesset perturbation theory for relativistic two-component Hamiltonians

    International Nuclear Information System (INIS)

    Helmich-Paris, Benjamin; Visscher, Lucas; Repisky, Michal

    2016-01-01

    We present a formulation of Laplace-transformed atomic orbital-based second-order Møller–Plesset perturbation theory (MP2) energies for two-component Hamiltonians in the Kramers-restricted formalism. This low-order scaling technique can be used to enable correlated relativistic calculations for large molecular systems. We show that the working equations to compute the relativistic MP2 energy differ by merely a change of algebra (quaternion instead of real) from their non-relativistic counterparts. With a proof-of-principle implementation we study the effect of the nuclear charge on the magnitude of half-transformed integrals and show that for light elements spin-free and spin-orbit MP2 energies are almost identical. Furthermore, we investigate the effect of separation of charge distributions on the Coulomb and exchange energy contributions, which show the same long-range decay with the inter-electronic/atomic distance as for non-relativistic MP2. A linearly scaling implementation is possible if the proper distance behavior is introduced to the quaternion Schwarz-type estimates as for non-relativistic MP2.

  6. Pd-Doped SnO2-Based Sensor Detecting Characteristic Fault Hydrocarbon Gases in Transformer Oil

    Directory of Open Access Journals (Sweden)

    Weigen Chen

    2013-01-01

    Full Text Available Methane (CH4, ethane (C2H6, ethylene (C2H4, and acetylene (C2C2 are important fault characteristic hydrocarbon gases dissolved in power transformer oil. Online monitoring these gaseous components and their generation rates can present the operational state of power transformer timely and effectively. Gas sensing technology is the most sticky and tricky point in online monitoring system. In this paper, pure and Pd-doped SnO2 nanoparticles were synthesized by hydrothermal method and characterized by X-ray powder diffraction, field-emission scanning electron microscopy, and energy dispersive X-ray spectroscopy, respectively. The gas sensors were fabricated by side-heated preparation, and their gas sensing properties against CH4, C2H6, C2H4, and C2H2 were measured. Pd doping increases the electric conductance of the prepared SnO2 sensors and improves their gas sensing performances to hydrocarbon gases. In addition based on the frontier molecular orbital theory, the highest occupied molecular orbital energy and the lowest unoccupied molecular orbital energy were calculated. Calculation results demonstrate that C2H4 has the highest occupied molecular orbital energy among CH4, C2H6, C2H4, and C2H2, which promotes charge transfer in gas sensing process, and SnO2 surfaces capture a relatively larger amount of electric charge from adsorbed C2H4.

  7. Techniques for Handling and Removal of Spectral Channels in Fourier Transform Synchrotron-Based Spectra

    International Nuclear Information System (INIS)

    Ibrahim, Amr; Predoi-Cross, Adriana; Teillet, Philippe M.

    2010-01-01

    Channel spectra are a big problem for those attempting to use synchrotron-based Fourier transform spectra for spectral lineshape studies. Due to the layout of the optical system at the CLS far-infrared beamline, the synchrotron beam undergoes unavoidable multiple reflections on the steering mirrors, beam splitter, several sets of windows, and filters. We present a method for eliminating channel spectra and compare the results of our technique with other methods available in the literature.

  8. Acoustic recognition of stress induced martensitic transformations in Cu-based shape memory alloys

    Czech Academy of Sciences Publication Activity Database

    Novák, Václav; Landa, Michal; Šittner, Petr

    2003-01-01

    Roč. 112, - (2003), s. 593-596 ISSN 1155-4339 R&D Projects: GA AV ČR IAA1048107; GA ČR GA106/01/0396 Institutional research plan: CEZ:AV0Z1010914 Keywords : shape memory alloys(SMA) * Cu-based SMA * Martensitic phase transformation * acoustic emission Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.319, year: 2003

  9. Comparison of theories of anisotropy in transformer oil-based magnetic fluids

    OpenAIRE

    Kúdelčík, Jozef; Bury, Peter; Drga, Jozef; Kopčanský, Peter; Závišová, Vlasta; Timko, Milan

    2013-01-01

    The external magnetic field in transformer oil-based magnetic fluids leads to the aggregation of magnetic nanoparticles and formation of clusters. These aggregations are the result of the interaction between the external magnetic field and the magnetic moments of the nanoparticles occurs. However, the temperature of magnetic fluids has also very important influence on the structural changes because the mechanism of thermal motion acts against the cluster creation. The acoustic spectroscopy ...

  10. A method for valuing architecture-based business transformation and measuring the value of solutions architecture

    OpenAIRE

    Slot, R.G.

    2010-01-01

    Enterprise and Solution Architecture are key in today’s business environment. It is surprising that the foundation and business case for these activities are nonexistent; the financial value for the business of these activities is largely undetermined. To determine business value of enterprise and solution architecture, this thesis shows how to measure and quantify, in business terms, the value of enterprise architecture-based on business transformation and the value of solution architecture.

  11. A laser printing based approach for printed electronics

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, T.; Hu, M.; Guo, Q.; Zhang, W.; Yang, J., E-mail: jyang@eng.uwo.ca [Department of Mechanical and Materials Engineering, Western University, London N6A 3K7 (Canada); Liu, Y.; Lau, W. [Chengdu Green Energy and Green Manufacturing Technology R& D Center, 355 Tengfei Road, 620107 Chengdu (China); Wang, X. [Department of Mechanical and Materials Engineering, Western University, London N6A 3K7 (Canada); Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2016-03-07

    Here we report a study of printing of electronics using an office use laser printer. The proposed method eliminates those critical disadvantages of solvent-based printing techniques by taking the advantages of electroless deposition and laser printing. The synthesized toner acts as a catalyst for the electroless copper deposition as well as an adhesion-promoting buffer layer between the substrate and deposited copper. The easy metallization of printed patterns and strong metal-substrate adhesion make it an especially effective method for massive production of flexible printed circuits. The proposed process is a high throughput, low cost, efficient, and environmentally benign method for flexible electronics manufacturing.

  12. Electronic properties of graphene-based bilayer systems

    Energy Technology Data Exchange (ETDEWEB)

    Rozhkov, A.V., E-mail: arozhkov@gmail.com [CEMS, RIKEN, Saitama 351-0198 (Japan); Institute for Theoretical and Applied Electrodynamics, Russian Academy of Sciences, 125412 Moscow (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141700 (Russian Federation); Sboychakov, A.O. [CEMS, RIKEN, Saitama 351-0198 (Japan); Institute for Theoretical and Applied Electrodynamics, Russian Academy of Sciences, 125412 Moscow (Russian Federation); Rakhmanov, A.L. [CEMS, RIKEN, Saitama 351-0198 (Japan); Institute for Theoretical and Applied Electrodynamics, Russian Academy of Sciences, 125412 Moscow (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141700 (Russian Federation); All-Russia Research Institute of Automatics, Moscow, 127055 (Russian Federation); Nori, Franco, E-mail: fnori@riken.jp [CEMS, RIKEN, Saitama 351-0198 (Japan); Physics Department, The University of Michigan, Ann Arbor, MI 48109-1040 (United States)

    2016-08-23

    This article reviews the theoretical and experimental work related to the electronic properties of bilayer graphene systems. Three types of bilayer stackings are discussed: the AA, AB, and twisted bilayer graphene. This review covers single-electron properties, effects of static electric and magnetic fields, bilayer-based mesoscopic systems, spin–orbit coupling, dc transport and optical response, as well as spontaneous symmetry violation and other interaction effects. The selection of the material aims to introduce the reader to the most commonly studied topics of theoretical and experimental research in bilayer graphene.

  13. A laser printing based approach for printed electronics

    International Nuclear Information System (INIS)

    Zhang, T.; Hu, M.; Guo, Q.; Zhang, W.; Yang, J.; Liu, Y.; Lau, W.; Wang, X.

    2016-01-01

    Here we report a study of printing of electronics using an office use laser printer. The proposed method eliminates those critical disadvantages of solvent-based printing techniques by taking the advantages of electroless deposition and laser printing. The synthesized toner acts as a catalyst for the electroless copper deposition as well as an adhesion-promoting buffer layer between the substrate and deposited copper. The easy metallization of printed patterns and strong metal-substrate adhesion make it an especially effective method for massive production of flexible printed circuits. The proposed process is a high throughput, low cost, efficient, and environmentally benign method for flexible electronics manufacturing.

  14. Design and application of discrete wavelet packet transform based multiresolution controller for liquid level system.

    Science.gov (United States)

    Paul, Rimi; Sengupta, Anindita

    2017-11-01

    A new controller based on discrete wavelet packet transform (DWPT) for liquid level system (LLS) has been presented here. This controller generates control signal using node coefficients of the error signal which interprets many implicit phenomena such as process dynamics, measurement noise and effect of external disturbances. Through simulation results on LLS problem, this controller is shown to perform faster than both the discrete wavelet transform based controller and conventional proportional integral controller. Also, it is more efficient in terms of its ability to provide better noise rejection. To overcome the wind up phenomenon by considering the saturation due to presence of actuator, anti-wind up technique is applied to the conventional PI controller and compared to the wavelet packet transform based controller. In this case also, packet controller is found better than the other ones. This similar work has been extended for analogous first order RC plant as well as second order plant also. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  15. Adaptive synchrosqueezing based on a quilted short-time Fourier transform

    Science.gov (United States)

    Berrian, Alexander; Saito, Naoki

    2017-08-01

    In recent years, the synchrosqueezing transform (SST) has gained popularity as a method for the analysis of signals that can be broken down into multiple components determined by instantaneous amplitudes and phases. One such version of SST, based on the short-time Fourier transform (STFT), enables the sharpening of instantaneous frequency (IF) information derived from the STFT, as well as the separation of amplitude-phase components corresponding to distinct IF curves. However, this SST is limited by the time-frequency resolution of the underlying window function, and may not resolve signals exhibiting diverse time-frequency behaviors with sufficient accuracy. In this work, we develop a framework for an SST based on a "quilted" short-time Fourier transform (SST-QSTFT), which allows adaptation to signal behavior in separate time-frequency regions through the use of multiple windows. This motivates us to introduce a discrete reassignment frequency formula based on a finite difference of the phase spectrum, ensuring computational accuracy for a wider variety of windows. We develop a theoretical framework for the SST-QSTFT in both the continuous and the discrete settings, and describe an algorithm for the automatic selection of optimal windows depending on the region of interest. Using synthetic data, we demonstrate the superior numerical performance of SST-QSTFT relative to other SST methods in a noisy context. Finally, we apply SST-QSTFT to audio recordings of animal calls to demonstrate the potential of our method for the analysis of real bioacoustic signals.

  16. Structure of nanoparticles in transformer oil-based magnetic fluids, anisotropy of acoustic attenuation

    International Nuclear Information System (INIS)

    Kúdelčík, Jozef; Bury, Peter; Kopčanský, Peter; Timko, Milan

    2015-01-01

    The anisotropy of acoustic attenuation in transformer oil-based magnetic fluids upon the external magnetic field was studied to discover the structure of nanoparticles. When a magnetic field is increased, the interaction between the external magnetic field and the magnetic moments of the nanoparticles leads to the aggregation of magnetic nanoparticles and following clusters formation. However, the temperature of magnetic fluids and the concentration of nanoparticles also have very important influence on the structural changes. The measurement of the dependence of the acoustic attenuation on the angle between the magnetic field direction and acoustic wave vector (anisotropy) can give the useful information about the structure of magnetic nanoparticles formations. In the present, the results of anisotropy measurements of the transformer oil-based magnetic fluids are described and using appropriate theory the basic parameters of clusters are calculated. On the basis of the performed calculations, the proportion of the acoustic wave energy used for excitation of the translational and rotational degrees of freedom was also established. - Highlights: • Nanoparticles formation in transformer oil-based magnetic fluids was investigated. • The anisotropy acoustic spectroscopy as the method of investigation was used. • The external conditions on the structure of magnetic fluids were studied. • The structure parameters using suitable theoretical model were determined

  17. Structure of nanoparticles in transformer oil-based magnetic fluids, anisotropy of acoustic attenuation

    Energy Technology Data Exchange (ETDEWEB)

    Kúdelčík, Jozef, E-mail: kudelcik@fyzika.uniza.sk [Department of Physics, University of Žilina, Univerzitná 1, 010 01 Žilina (Slovakia); Bury, Peter [Department of Physics, University of Žilina, Univerzitná 1, 010 01 Žilina (Slovakia); Kopčanský, Peter; Timko, Milan [Department of Magnetism, IEP SAS, Watsonova 47, 040 01 Košice (Slovakia)

    2015-08-15

    The anisotropy of acoustic attenuation in transformer oil-based magnetic fluids upon the external magnetic field was studied to discover the structure of nanoparticles. When a magnetic field is increased, the interaction between the external magnetic field and the magnetic moments of the nanoparticles leads to the aggregation of magnetic nanoparticles and following clusters formation. However, the temperature of magnetic fluids and the concentration of nanoparticles also have very important influence on the structural changes. The measurement of the dependence of the acoustic attenuation on the angle between the magnetic field direction and acoustic wave vector (anisotropy) can give the useful information about the structure of magnetic nanoparticles formations. In the present, the results of anisotropy measurements of the transformer oil-based magnetic fluids are described and using appropriate theory the basic parameters of clusters are calculated. On the basis of the performed calculations, the proportion of the acoustic wave energy used for excitation of the translational and rotational degrees of freedom was also established. - Highlights: • Nanoparticles formation in transformer oil-based magnetic fluids was investigated. • The anisotropy acoustic spectroscopy as the method of investigation was used. • The external conditions on the structure of magnetic fluids were studied. • The structure parameters using suitable theoretical model were determined.

  18. Electronic Government and Electronic Participation

    NARCIS (Netherlands)

    Tambouris, E; Scholl, H.J.; Janssen, M.F.W.H.A.; Wimmer, M.A.; Tarabanis, K; Gascó, M; Klievink, A.J.; Lindgren, I; Milano, M; Panagiotopoulos, P; Pardo, T.A.; Parycek, P; Sæbø, Ø

    2016-01-01

    Electronic government and electronic participation continue to transform the public sector and society worldwide and are constantly being transformed themselves by emerging information and communication technologies.This book presents papers from the 14th International Federation for Information

  19. Electronic Government and Electronic Participation

    NARCIS (Netherlands)

    Tambouris, E.; Scholl, H.J.; Janssen, M.F.W.H.A.; Wimmer, M.A.; Tarabanis, K.; Gascó, M.; Klievink, A.J.; Lindgren, I.; Milano, M.; Panagiotopoulos, P.; Pardo, T.A.; Parycek, P.; Sæbø, O.

    2015-01-01

    Electronic government and electronic participation continue to transform the public sector and society worldwide and are constantly being transformed themselves by emerging information and communication technologies. This book presents papers from the 14th International Federation for Information

  20. Electronics and Algorithms for HOM Based Beam Diagnostics

    Science.gov (United States)

    Frisch, Josef; Baboi, Nicoleta; Eddy, Nathan; Nagaitsev, Sergei; Hensler, Olaf; McCormick, Douglas; May, Justin; Molloy, Stephen; Napoly, Olivier; Paparella, Rita; Petrosyan, Lyudvig; Ross, Marc; Simon, Claire; Smith, Tonee

    2006-11-01

    The signals from the Higher Order Mode (HOM) ports on superconducting cavities can be used as beam position monitors and to do survey structure alignment. A HOM-based diagnostic system has been installed to instrument both couplers on each of the 40 cryogenic accelerating structures in the DESY TTF2 Linac. The electronics uses a single stage down conversion from the 1.7 GHz HOM spectral line to a 20MHz IF which has been digitized. The electronics is based on low cost surface mount components suitable for large scale production. The analysis of the HOM data is based on Singular Value Decomposition. The response of the OM modes is calibrated using conventional BPMs.

  1. Wireless implantable electronic platform for chronic fluorescent-based biosensors.

    Science.gov (United States)

    Valdastri, Pietro; Susilo, Ekawahyu; Förster, Thilo; Strohhöfer, Christof; Menciassi, Arianna; Dario, Paolo

    2011-06-01

    The development of a long-term wireless implantable biosensor based on fluorescence intensity measurement poses a number of technical challenges, ranging from biocompatibility to sensor stability over time. One of these challenges is the design of a power efficient and miniaturized electronics, enabling the biosensor to move from bench testing to long term validation, up to its final application in human beings. In this spirit, we present a wireless programmable electronic platform for implantable chronic monitoring of fluorescent-based autonomous biosensors. This system is able to achieve extremely low power operation with bidirectional telemetry, based on the IEEE802.15.4-2003 protocol, thus enabling over three-year battery lifetime and wireless networking of multiple sensors. During the performance of single fluorescent-based sensor measurements, the circuit drives a laser diode, for sensor excitation, and acquires the amplified signals from four different photodetectors. In vitro functionality was preliminarily tested for both glucose and calcium monitoring, simply by changing the analyte-binding protein of the biosensor. Electronics performance was assessed in terms of timing, power consumption, tissue exposure to electromagnetic fields, and in vivo wireless connectivity. The final goal of the presented platform is to be integrated in a complete system for blood glucose level monitoring that may be implanted for at least one year under the skin of diabetic patients. Results reported in this paper may be applied to a wide variety of biosensors based on fluorescence intensity measurement.

  2. Portable audio electronics for impedance-based measurements in microfluidics

    International Nuclear Information System (INIS)

    Wood, Paul; Sinton, David

    2010-01-01

    We demonstrate the use of audio electronics-based signals to perform on-chip electrochemical measurements. Cell phones and portable music players are examples of consumer electronics that are easily operated and are ubiquitous worldwide. Audio output (play) and input (record) signals are voltage based and contain frequency and amplitude information. A cell phone, laptop soundcard and two compact audio players are compared with respect to frequency response; the laptop soundcard provides the most uniform frequency response, while the cell phone performance is found to be insufficient. The audio signals in the common portable music players and laptop soundcard operate in the range of 20 Hz to 20 kHz and are found to be applicable, as voltage input and output signals, to impedance-based electrochemical measurements in microfluidic systems. Validated impedance-based measurements of concentration (0.1–50 mM), flow rate (2–120 µL min −1 ) and particle detection (32 µm diameter) are demonstrated. The prevailing, lossless, wave audio file format is found to be suitable for data transmission to and from external sources, such as a centralized lab, and the cost of all hardware (in addition to audio devices) is ∼10 USD. The utility demonstrated here, in combination with the ubiquitous nature of portable audio electronics, presents new opportunities for impedance-based measurements in portable microfluidic systems. (technical note)

  3. Multisensor signal denoising based on matching synchrosqueezing wavelet transform for mechanical fault condition assessment

    Science.gov (United States)

    Yi, Cancan; Lv, Yong; Xiao, Han; Huang, Tao; You, Guanghui

    2018-04-01

    Since it is difficult to obtain the accurate running status of mechanical equipment with only one sensor, multisensor measurement technology has attracted extensive attention. In the field of mechanical fault diagnosis and condition assessment based on vibration signal analysis, multisensor signal denoising has emerged as an important tool to improve the reliability of the measurement result. A reassignment technique termed the synchrosqueezing wavelet transform (SWT) has obvious superiority in slow time-varying signal representation and denoising for fault diagnosis applications. The SWT uses the time-frequency reassignment scheme, which can provide signal properties in 2D domains (time and frequency). However, when the measured signal contains strong noise components and fast varying instantaneous frequency, the performance of SWT-based analysis still depends on the accuracy of instantaneous frequency estimation. In this paper, a matching synchrosqueezing wavelet transform (MSWT) is investigated as a potential candidate to replace the conventional synchrosqueezing transform for the applications of denoising and fault feature extraction. The improved technology utilizes the comprehensive instantaneous frequency estimation by chirp rate estimation to achieve a highly concentrated time-frequency representation so that the signal resolution can be significantly improved. To exploit inter-channel dependencies, the multisensor denoising strategy is performed by using a modulated multivariate oscillation model to partition the time-frequency domain; then, the common characteristics of the multivariate data can be effectively identified. Furthermore, a modified universal threshold is utilized to remove noise components, while the signal components of interest can be retained. Thus, a novel MSWT-based multisensor signal denoising algorithm is proposed in this paper. The validity of this method is verified by numerical simulation, and experiments including a rolling

  4. A Rigid Image Registration Based on the Nonsubsampled Contourlet Transform and Genetic Algorithms

    Directory of Open Access Journals (Sweden)

    Nasreddine Taleb

    2010-09-01

    Full Text Available Image registration is a fundamental task used in image processing to match two or more images taken at different times, from different sensors or from different viewpoints. The objective is to find in a huge search space of geometric transformations, an acceptable accurate solution in a reasonable time to provide better registered images. Exhaustive search is computationally expensive and the computational cost increases exponentially with the number of transformation parameters and the size of the data set. In this work, we present an efficient image registration algorithm that uses genetic algorithms within a multi-resolution framework based on the Non-Subsampled Contourlet Transform (NSCT. An adaptable genetic algorithm for registration is adopted in order to minimize the search space. This approach is used within a hybrid scheme applying the two techniques fitness sharing and elitism. Two NSCT based methods are proposed for registration. A comparative study is established between these methods and a wavelet based one. Because the NSCT is a shift-invariant multidirectional transform, the second method is adopted for its search speeding up property. Simulation results clearly show that both proposed techniques are really promising methods for image registration compared to the wavelet approach, while the second technique has led to the best performance results of all. Moreover, to demonstrate the effectiveness of these methods, these registration techniques have been successfully applied to register SPOT, IKONOS and Synthetic Aperture Radar (SAR images. The algorithm has been shown to work perfectly well for multi-temporal satellite images as well, even in the presence of noise.

  5. A rigid image registration based on the nonsubsampled contourlet transform and genetic algorithms.

    Science.gov (United States)

    Meskine, Fatiha; Chikr El Mezouar, Miloud; Taleb, Nasreddine

    2010-01-01

    Image registration is a fundamental task used in image processing to match two or more images taken at different times, from different sensors or from different viewpoints. The objective is to find in a huge search space of geometric transformations, an acceptable accurate solution in a reasonable time to provide better registered images. Exhaustive search is computationally expensive and the computational cost increases exponentially with the number of transformation parameters and the size of the data set. In this work, we present an efficient image registration algorithm that uses genetic algorithms within a multi-resolution framework based on the Non-Subsampled Contourlet Transform (NSCT). An adaptable genetic algorithm for registration is adopted in order to minimize the search space. This approach is used within a hybrid scheme applying the two techniques fitness sharing and elitism. Two NSCT based methods are proposed for registration. A comparative study is established between these methods and a wavelet based one. Because the NSCT is a shift-invariant multidirectional transform, the second method is adopted for its search speeding up property. Simulation results clearly show that both proposed techniques are really promising methods for image registration compared to the wavelet approach, while the second technique has led to the best performance results of all. Moreover, to demonstrate the effectiveness of these methods, these registration techniques have been successfully applied to register SPOT, IKONOS and Synthetic Aperture Radar (SAR) images. The algorithm has been shown to work perfectly well for multi-temporal satellite images as well, even in the presence of noise.

  6. The kinetics of phase transformations of undercooled austenite of the Mn-Ni iron based model alloy

    OpenAIRE

    E. Rożniata; R. Dziurka; J. Pacyna

    2011-01-01

    Purpose: Present work corresponds to the research on the kinetics of phase transformations of undercooled austenite of Mn-Ni iron based model alloy. The kinetics of phase transformations of undercooled austenite of investigated alloy was presented on CCT diagram (continuous cooling transformation). Also the methodology of a dilatometric samples preparation and the method of the critical points determination were described.Design/methodology/approach: The austenitising temperature was defined ...

  7. Recent advances in molecular electronics based on carbon nanotubes.

    Science.gov (United States)

    Bourgoin, Jean-Philippe; Campidelli, Stéphane; Chenevier, Pascale; Derycke, Vincent; Filoramo, Arianna; Goffman, Marcelo F

    2010-01-01

    Carbon nanotubes (CNTs) have exceptional physical properties that make them one of the most promising building blocks for future nanotechnologies. They may in particular play an important role in the development of innovative electronic devices in the fields of flexible electronics, ultra-high sensitivity sensors, high frequency electronics, opto-electronics, energy sources and nano-electromechanical systems (NEMS). Proofs of concept of several high performance devices already exist, usually at the single device level, but there remain many serious scientific issues to be solved before the viability of such routes can be evaluated. In particular, the main concern regards the controlled synthesis and positioning of nanotubes. In our opinion, truly innovative use of these nano-objects will come from: (i) the combination of some of their complementary physical properties, such as combining their electrical and mechanical properties, (ii) the combination of their properties with additional benefits coming from other molecules grafted on the nanotubes, and (iii) the use of chemically- or bio-directed self-assembly processes to allow the efficient combination of several devices into functional arrays or circuits. In this article, we outline the main issues concerning the development of carbon nanotubes based electronics applications and review our recent results in the field.

  8. Electron dose map inversion based on several algorithms

    International Nuclear Information System (INIS)

    Li Gui; Zheng Huaqing; Wu Yican; Fds Team

    2010-01-01

    The reconstruction to the electron dose map in radiation therapy was investigated by constructing the inversion model of electron dose map with different algorithms. The inversion model of electron dose map based on nonlinear programming was used, and this model was applied the penetration dose map to invert the total space one. The realization of this inversion model was by several inversion algorithms. The test results with seven samples show that except the NMinimize algorithm, which worked for just one sample, with great error,though,all the inversion algorithms could be realized to our inversion model rapidly and accurately. The Levenberg-Marquardt algorithm, having the greatest accuracy and speed, could be considered as the first choice in electron dose map inversion.Further tests show that more error would be created when the data close to the electron range was used (tail error). The tail error might be caused by the approximation of mean energy spectra, and this should be considered to improve the method. The time-saving and accurate algorithms could be used to achieve real-time dose map inversion. By selecting the best inversion algorithm, the clinical need in real-time dose verification can be satisfied. (authors)

  9. OBS Data Denoising Based on Compressed Sensing Using Fast Discrete Curvelet Transform

    Science.gov (United States)

    Nan, F.; Xu, Y.

    2017-12-01

    OBS (Ocean Bottom Seismometer) data denoising is an important step of OBS data processing and inversion. It is necessary to get clearer seismic phases for further velocity structure analysis. Traditional methods for OBS data denoising include band-pass filter, Wiener filter and deconvolution etc. (Liu, 2015). Most of these filtering methods are based on Fourier Transform (FT). Recently, the multi-scale transform methods such as wavelet transform (WT) and Curvelet transform (CvT) are widely used for data denoising in various applications. The FT, WT and CvT could represent signal sparsely and separate noise in transform domain. They could be used in different cases. Compared with Curvelet transform, the FT has Gibbs phenomenon and it cannot handle points discontinuities well. WT is well localized and multi scale, but it has poor orientation selectivity and could not handle curves discontinuities well. CvT is a multiscale directional transform that could represent curves with only a small number of coefficients. It provide an optimal sparse representation of objects with singularities along smooth curves, which is suitable for seismic data processing. As we know, different seismic phases in OBS data are showed as discontinuous curves in time domain. Hence, we promote to analysis the OBS data via CvT and separate the noise in CvT domain. In this paper, our sparsity-promoting inversion approach is restrained by L1 condition and we solve this L1 problem by using modified iteration thresholding. Results show that the proposed method could suppress the noise well and give sparse results in Curvelet domain. Figure 1 compares the Curvelet denoising method with Wavelet method on the same iterations and threshold through synthetic example. a)Original data. b) Add-noise data. c) Denoised data using CvT. d) Denoised data using WT. The CvT can well eliminate the noise and has better result than WT. Further we applied the CvT denoise method for the OBS data processing. Figure 2a

  10. Spatially resolved electron density and electron energy distribution function in Ar magnetron plasmas used for sputter-deposition of ZnO-based thin films

    Energy Technology Data Exchange (ETDEWEB)

    Maaloul, L.; Gangwar, R. K.; Morel, S.; Stafford, L., E-mail: luc.stafford@umontreal.ca [Département de Physique, Université de Montréal, Montréal, Québec H3C 3J7 (Canada)

    2015-11-15

    Langmuir probe and trace rare gases optical emission spectroscopy were used to analyze the spatial structure of the electron density and electron energy distribution function (EEDF) in a cylindrical Ar magnetron plasma reactor used for sputter-deposition of ZnO-based thin films. While a typical Bessel (zero order) diffusion profile was observed along the radial direction for the number density of charged particles at 21 cm from the ZnO target, a significant rise of these populations with respect to the Bessel function was seen in the center of the reactor at 4 cm from the magnetron surface. As for the EEDF, it was found to transform from a more or less Maxwellian far from the target to a two-temperature Maxwellian with a depletion of high-energy electrons where magnetic field confinement effects become important. No significant change in the behavior of the electron density and EEDF across a wide range of pressures (5–100 mTorr) and self-bias voltages (115–300 V) was observed during magnetron sputtering of Zn, ZnO, and In{sub 2}O{sub 3} targets. This indicates that sputtering of Zn, In, and O atoms do not play a very significant role on the electron particle balance and electron heating dynamics, at least over the range of experimental conditions investigated.

  11. Towards model-based testing of electronic funds transfer systems

    OpenAIRE

    Asaadi, H.R.; Khosravi, R.; Mousavi, M.R.; Noroozi, N.

    2010-01-01

    We report on our first experience with applying model-based testing techniques to an operational Electronic Funds Transfer (EFT) switch. The goal is to test the conformance of the EFT switch to the standard flows described by the ISO 8583 standard. To this end, we first make a formalization of the transaction flows specified in the ISO 8583 standard in terms of a Labeled Transition System (LTS). This formalization paves the way for model-based testing based on the formal notion of Input-Outpu...

  12. Nanosecond pulse-width electron diode based on dielectric wall accelerator technology

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Quantang, E-mail: zhaoquantang@impcas.ac.cn [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Zhang, Z.M.; Yuan, P.; Cao, S.C.; Shen, X.K.; Jing, Y. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Yu, C.S. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Li, Z.P.; Liu, M.; Xiao, R.Q. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Zong, Y.; Wang, Y.R. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Zhao, H.W. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2013-11-21

    An electron diode using a short section of dielectric wall accelerator (DWA) has been under development at the Institute of Modern Physics (IMP), Chinese Academy of Sciences. Tests have been carried out with spark gap switches triggered by lasers. The stack voltage efficiency of a four-layer of Blumleins reached about 60–70% with gas filled spark gap switching. The generated pulse voltage of peak amplitude of 23 kV and pulse width of 5 ns is used to extract and accelerate an electron beam of 320 mA, measured by a fast current transformer. A nanosecond pulse width electron diode was achieved successfully. Furthermore, the principle of a DWA is well proven and the development details and discussions are presented in this article. -- Highlights: •The key technology of DWA, including switches and pulse forming lines were studied. •The SiC PCSS obtained from Shanghai Institute were tested. •Two layers ZIP lines (new structure) and four layers Blumlein lines were studied with laser triggered spark gap switches. •A nanosecond pulse-width electron diode based on DWA technologies is achieved and studied experimentally. •The principle of DWA is also proved by the diode.

  13. Effects of composition on the order-disorder transformation in Ni-Cr based alloys

    International Nuclear Information System (INIS)

    Marucco, A.

    1991-01-01

    The Ni-Cr based alloys undergo an ordering transformation, due to the formation of an ordered Ni 2 Cr phase, which causes a lattice contraction and it is responsisble for ''negative creep'' or excessive stresses in constrained components. A short-range ordered (SRO) structure develops in the matrix phase after solution treatment and at early stages of ageing, which can transform to a long-range ordered (LRO) structure, depending on the alloy composition and on time and temperature of ageing, upon prolonged annealing below the critical temperature. In stoichiometric Ni 2 Cr alloy LRO forms in a few hours, but in off-stoichiometric alloys the transformation kinetics are very sluggish and LRO takes several tens of thousands of hours to form, when it forms. The ordering behaviours of stoichiometric Ni 2 Cr and Ni 3 Cr were studied by means of isothermal treatments in the temperature range 450-600degC for different ageing times up to 30 000 h, followed by lattice parameter measurements by X-ray diffraction and electrical resistivity measurements. Similar studies performed on a series of ternary Ni-Cr-Fe alloys revealed the dependence of the degree of order on Cr concentration and a markedly delaying influence of Fe on the ordering kinetics. Finally, long-term microstructural stability of some commercial Ni-Cr based alloys, widely used for high temperature applications, have been studied: the ordering behaviour and associated microstructural changes are discussed in this paper

  14. Fast digital envelope detector based on generalized harmonic wavelet transform for BOTDR performance improvement

    International Nuclear Information System (INIS)

    Yang, Wei; Yang, Yuanhong; Yang, Mingwei

    2014-01-01

    We propose a fast digital envelope detector (DED) based on the generalized harmonic wavelet transform to improve the performance of coherent heterodyne Brillouin optical time domain reflectometry. The proposed DED can obtain undistorted envelopes due to the zero phase-shift ideal bandpass filter (BPF) characteristics of the generalized harmonic wavelet (GHW). Its envelope average ability benefits from the passband designing flexibility of the GHW, and its demodulation speed can be accelerated by using a fast algorithm that only analyses signals of interest within the passband of the GHW with reduced computational complexity. The feasibility and advantage of the proposed DED are verified by simulations and experiments. With an optimized bandwidth, Brillouin frequency shift accuracy improvements of 19.4% and 11.14%, as well as envelope demodulation speed increases of 39.1% and 24.9%, are experimentally attained by the proposed DED over Hilbert transform (HT) and Morlet wavelet transform (MWT) based DEDs, respectively. Spatial resolution by the proposed DED is undegraded, which is identical to the undegraded value by HT-DED with an allpass filter characteristic and better than the degraded value by MWT-DED with a Gaussian BPF characteristic. (paper)

  15. An effective approach to attenuate random noise based on compressive sensing and curvelet transform

    International Nuclear Information System (INIS)

    Liu, Wei; Cao, Siyuan; Zu, Shaohuan; Chen, Yangkang

    2016-01-01

    Random noise attenuation is an important step in seismic data processing. In this paper, we propose a novel denoising approach based on compressive sensing and the curvelet transform. We formulate the random noise attenuation problem as an L _1 norm regularized optimization problem. We propose to use the curvelet transform as the sparse transform in the optimization problem to regularize the sparse coefficients in order to separate signal and noise and to use the gradient projection for sparse reconstruction (GPSR) algorithm to solve the formulated optimization problem with an easy implementation and a fast convergence. We tested the performance of our proposed approach on both synthetic and field seismic data. Numerical results show that the proposed approach can effectively suppress the distortion near the edge of seismic events during the noise attenuation process and has high computational efficiency compared with the traditional curvelet thresholding and iterative soft thresholding based denoising methods. Besides, compared with f-x deconvolution, the proposed denoising method is capable of eliminating the random noise more effectively while preserving more useful signals. (paper)

  16. Atmospheric pressure plasma jet with high-voltage power supply based on piezoelectric transformer.

    Science.gov (United States)

    Babij, Michał; Kowalski, Zbigniew W; Nitsch, Karol; Silberring, Jerzy; Gotszalk, Teodor

    2014-05-01

    The dielectric barrier discharge plasma jet, an example of the nonthermal atmospheric pressure plasma jet (APPJ), generates low-temperature plasmas that are suitable for the atomization of volatile species and can also be served as an ionization source for ambient mass and ion mobility spectrometry. A new design of APPJ for mass spectrometry has been built in our group. In these plasma sources magnetic transformers (MTs) and inductors are typically used in power supplies but they present several drawbacks that are even more evident when dealing with high-voltage normally used in APPJs. To overcome these disadvantages, high frequency generators with the absence of MT are proposed in the literature. However, in the case of miniaturized APPJs these conventional power converters, built of ferromagnetic cores and inductors or by means of LC resonant tank circuits, are not so useful as piezoelectric transformer (PT) based power converters due to bulky components and small efficiency. We made and examined a novel atmospheric pressure plasma jet with PT supplier served as ionization source for ambient mass spectrometry, and especially mobile spectrometry where miniaturization, integration of components, and clean plasma are required. The objective of this paper is to describe the concept, design, and implementation of this miniaturized piezoelectric transformer-based atmospheric pressure plasma jet.

  17. Cognitive Artificial Intelligence Method for Interpreting Transformer Condition Based on Maintenance Data

    Directory of Open Access Journals (Sweden)

    Karel Octavianus Bachri

    2017-07-01

    Full Text Available A3S(Arwin-Adang-Aciek-Sembiring is a method of information fusion at a single observation and OMA3S(Observation Multi-time A3S is a method of information fusion for time-series data. This paper proposes OMA3S-based Cognitive Artificial-Intelligence method for interpreting Transformer Condition, which is calculated based on maintenance data from Indonesia National Electric Company (PLN. First, the proposed method is tested using the previously published data, and then followed by implementation on maintenance data. Maintenance data are fused to obtain part condition, and part conditions are fused to obtain transformer condition. Result shows proposed method is valid for DGA fault identification with the average accuracy of 91.1%. The proposed method not only can interpret the major fault, it can also identify the minor fault occurring along with the major fault, allowing early warning feature. Result also shows part conditions can be interpreted using information fusion on maintenance data, and the transformer condition can be interpreted using information fusion on part conditions. The future works on this research is to gather more data, to elaborate more factors to be fused, and to design a cognitive processor that can be used to implement this concept of intelligent instrumentation.

  18. Application of affinity propagation algorithm based on manifold distance for transformer PD pattern recognition

    Science.gov (United States)

    Wei, B. G.; Huo, K. X.; Yao, Z. F.; Lou, J.; Li, X. Y.

    2018-03-01

    It is one of the difficult problems encountered in the research of condition maintenance technology of transformers to recognize partial discharge (PD) pattern. According to the main physical characteristics of PD, three models of oil-paper insulation defects were set up in laboratory to study the PD of transformers, and phase resolved partial discharge (PRPD) was constructed. By using least square method, the grey-scale images of PRPD were constructed and features of each grey-scale image were 28 box dimensions and 28 information dimensions. Affinity propagation algorithm based on manifold distance (AP-MD) for transformers PD pattern recognition was established, and the data of box dimension and information dimension were clustered based on AP-MD. Study shows that clustering result of AP-MD is better than the results of affinity propagation (AP), k-means and fuzzy c-means algorithm (FCM). By choosing different k values of k-nearest neighbor, we find clustering accuracy of AP-MD falls when k value is larger or smaller, and the optimal k value depends on sample size.

  19. Atmospheric pressure plasma jet with high-voltage power supply based on piezoelectric transformer

    Energy Technology Data Exchange (ETDEWEB)

    Babij, Michał; Kowalski, Zbigniew W., E-mail: zbigniew.w.kowalski@pwr.wroc.pl; Nitsch, Karol; Gotszalk, Teodor [Wrocław University of Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław (Poland); Silberring, Jerzy [AGH University of Science and Technology, Al. A. Mickiewicza 30, 30-059 Kraków (Poland)

    2014-05-15

    The dielectric barrier discharge plasma jet, an example of the nonthermal atmospheric pressure plasma jet (APPJ), generates low-temperature plasmas that are suitable for the atomization of volatile species and can also be served as an ionization source for ambient mass and ion mobility spectrometry. A new design of APPJ for mass spectrometry has been built in our group. In these plasma sources magnetic transformers (MTs) and inductors are typically used in power supplies but they present several drawbacks that are even more evident when dealing with high-voltage normally used in APPJs. To overcome these disadvantages, high frequency generators with the absence of MT are proposed in the literature. However, in the case of miniaturized APPJs these conventional power converters, built of ferromagnetic cores and inductors or by means of LC resonant tank circuits, are not so useful as piezoelectric transformer (PT) based power converters due to bulky components and small efficiency. We made and examined a novel atmospheric pressure plasma jet with PT supplier served as ionization source for ambient mass spectrometry, and especially mobile spectrometry where miniaturization, integration of components, and clean plasma are required. The objective of this paper is to describe the concept, design, and implementation of this miniaturized piezoelectric transformer-based atmospheric pressure plasma jet.

  20. A New Method for Multisensor Data Fusion Based on Wavelet Transform in a Chemical Plant

    Directory of Open Access Journals (Sweden)

    Karim Salahshoor

    2014-07-01

    Full Text Available This paper presents a new multi-sensor data fusion method based on the combination of wavelet transform (WT and extended Kalman filter (EKF. Input data are first filtered by a wavelet transform via Daubechies wavelet “db4” functions and the filtered data are then fused based on variance weights in terms of minimum mean square error. The fused data are finally treated by extended Kalman filter for the final state estimation. The recent data are recursively utilized to apply wavelet transform and extract the variance of the updated data, which makes it suitable to be applied to both static and dynamic systems corrupted by noisy environments. The method has suitable performance in state estimation in comparison with the other alternative algorithms. A three-tank benchmark system has been adopted to comparatively demonstrate the performance merits of the method compared to a known algorithm in terms of efficiently satisfying signal-tonoise (SNR and minimum square error (MSE criteria.