Increasing availability of genomic data and sophistication of analytical methodology in fungi has elevated the need for functional genomics tools in these organisms. Gene deletion is a critical tool for functional analysis. The targeted deletion of genes requires both a suitable method for the trans...
von Arnim Albrecht G
2009-05-01
Full Text Available Abstract Background Plant genome sequencing has resulted in the identification of a large number of uncharacterized genes. To investigate these unknown gene functions, several transient transformation systems have been developed as quick and convenient alternatives to the lengthy transgenic assay. These transient assays include biolistic bombardment, protoplast transfection and Agrobacterium-mediated transient transformation, each having advantages and disadvantages depending on the research purposes. Results We present a novel transient assay based on cocultivation of young Arabidopsis (Arabidopsis thaliana seedlings with Agrobacterium tumefaciens in the presence of a surfactant which does not require any dedicated equipment and can be carried out within one week from sowing seeds to protein analysis. This Fast Agro-mediated Seedling Transformation (FAST was used successfully to express a wide variety of constructs driven by different promoters in Arabidopsis seedling cotyledons (but not roots in diverse genetic backgrounds. Localizations of three previously uncharacterized proteins were identified by cotransformation with fluorescent organelle markers. The FAST procedure requires minimal handling of seedlings and was also adaptable for use in 96-well plates. The high transformation efficiency of the FAST procedure enabled protein detection from eight transformed seedlings by immunoblotting. Protein-protein interaction, in this case HY5 homodimerization, was readily detected in FAST-treated seedlings with Förster resonance energy transfer and bimolecular fluorescence complementation techniques. Initial tests demonstrated that the FAST procedure can also be applied to other dicot and monocot species, including tobacco, tomato, rice and switchgrass. Conclusion The FAST system provides a rapid, efficient and economical assay of gene function in intact plants with minimal manual handling and without dedicated device. This method is potentially
Transform methods for solving partial differential equations
Duffy, Dean G
2004-01-01
Transform methods provide a bridge between the commonly used method of separation of variables and numerical techniques for solving linear partial differential equations. While in some ways similar to separation of variables, transform methods can be effective for a wider class of problems. Even when the inverse of the transform cannot be found analytically, numeric and asymptotic techniques now exist for their inversion, and because the problem retains some of its analytic aspect, one can gain greater physical insight than typically obtained from a purely numerical approach. Transform Methods for Solving Partial Differential Equations, Second Edition illustrates the use of Laplace, Fourier, and Hankel transforms to solve partial differential equations encountered in science and engineering. The author has expanded the second edition to provide a broader perspective on the applicability and use of transform methods and incorporated a number of significant refinements: New in the Second Edition: ·...
A noise measurement method for transformers
A transformer manufacturer (Pauwels International in Mechelen, Belgium) and an automation firm (Simac Techniek in Veldhoven, Netherlands) developed a fast and simple method to measure the sound pressure of transformers, based on the method 'Triggered Intensity', part of the IEC-551 guideline. 5 figs
Lifetime estimation methods in power transformer insulation
Mohammad Ali Taghikhani
2012-01-01
Mineral oil in the power transformer has an important role in the cooling, insulation aging and chemical reactions such as oxidation. Oil temperature increases will cause quality loss. The oil should be regularly control in necessary time. Studies have been done on power transformers oils that are used in different age in Iranian power grid to identify the true relationship between age and other characteristics of power transformer oil. In this paper the first method to estimate the life of p...
DISCUSSION METHODS: MODIFICATION AND TRANSFORMATION
Abbasova, A.A.
2016-03-01
Full Text Available This article is about how to the importance of selecting the optimal methods of stimulation and motivation to learn. In modern conditions it is very important that the teacher gave the students ready knowledge, and pointed the way for the acquisition of knowledge, taught to acquire knowledge. This requires the selection of effective forms of language and literature work with texts of different types and styles of speech, listening, speaking. In this regard, special attention should be given lessons of speech development. There is a special group of methods to stimulate the development of communicative competence. Among them, and the method of discussion, which is increasingly being used in the classroom in the Russian language
Nataf transformation based point estimate method
LI HongShuang; L(U) ZhenZhou; YUAN XiuKai
2008-01-01
Structural probabilistic analysis quantifies the effect of input random variables, such as material proper-ties, geometrical parameters and loading conditions, on the structural responses. The point estimate method (PEM) is a direct and easy-used way to perform the structural probabilistic analysis in practice. In this paper, a novel and efficient point estimate method is proposed for computing the first four statistical moments of structural response which is a function of input random variables. The method adopts Nataf transformation to replace Rosenblatt transformation in conventional point estimate method. Because of the nature of engineering problems and limited statistical data, the joint probability density function (PDF) of all input random variables is hard to acquire, but it must be known in Rosenblatt transformation. A more common case is that the marginal PDF of each random variable and the correlation matrix are available, which just satisfy the service condition of Nataf transformation. Hence the Nataf transformation based point estimate method is particularly suitable for engineering applications. The comparison be-tween the proposed method and the conventional point estimate method shows that (1) they are equiva-lent when all random variables are mutually independent; (2) if the marginal PDFs and the correlation matrix are known, the conventional PEM cannot be applicable, but the proposed method can give a ra-tional approximation. Finally, the procedure is demonstrated in detail through a simple illustration.
Digital Autofocusing Method Based on Contourlet Transform
无
2007-01-01
The autofocusing technique based on contourlet transform is discussed in this paper and an autofocusing method is proposed for images with much information in certain directions. The experimental results show that theproposed method can focus accurately and the sensitivity ratio is higher than that of the other autofocusing methods based on conventional image processing
Discrete fourier transform (DFT) analysis for applications using iterative transform methods
Dean, Bruce H. (Inventor)
2012-01-01
According to various embodiments, a method is provided for determining aberration data for an optical system. The method comprises collecting a data signal, and generating a pre-transformation algorithm. The data is pre-transformed by multiplying the data with the pre-transformation algorithm. A discrete Fourier transform of the pre-transformed data is performed in an iterative loop. The method further comprises back-transforming the data to generate aberration data.
Multiphase Transformer Modelling using Finite Element Method
Nor Azizah Mohd Yusoff
2015-03-01
Full Text Available In the year of 1970 saw the starting invention of the five-phase motor as the milestone in advanced electric motor. Through the years, there are many researchers, which passionately worked towards developing for multiphase drive system. They developed a static transformation system to obtain a multiphase supply from the available three-phase supply. This idea gives an influence for further development in electric machines as an example; an efficient solution for bulk power transfer. This paper highlighted the detail descriptions that lead to five-phase supply with fixed voltage and frequency by using Finite-Element Method (FEM. Identifying of specification on a real transformer had been done before applied into software modeling. Therefore, Finite-Element Method provides clearly understandable in terms of visualize the geometry modeling, connection scheme and output waveform.
Transformation methods in the study of nonlinear partial differential equations
Sophocleous, Christodoulos
1991-01-01
Transformation methods are perhaps the most powerful analytic tool currently available in the study of nonlinear partial differential equations. Transformations may be classified into two categories: category I includes transformations of the dependent and independent variables of a given partial differential equation and category II additionally includes transformations of the derivatives of the dependent variables. In part I of this thesis our principal attention is focused on transform...
Transformative, Mixed Methods Checklist for Psychological Research with Mexican Americans
Canales, Genevieve
2013-01-01
This is a description of the creation of a research methods tool, the "Transformative, Mixed Methods Checklist for Psychological Research With Mexican Americans." For conducting literature reviews of and planning mixed methods studies with Mexican Americans, it contains evaluative criteria calling for transformative mixed methods, perspectives…
Performance analysis of image fusion methods in transform domain
Choi, Yoonsuk; Sharifahmadian, Ershad; Latifi, Shahram
2013-05-01
Image fusion involves merging two or more images in such a way as to retain the most desirable characteristics of each. There are various image fusion methods and they can be classified into three main categories: i) Spatial domain, ii) Transform domain, and iii) Statistical domain. We focus on the transform domain in this paper as spatial domain methods are primitive and statistical domain methods suffer from a significant increase of computational complexity. In the field of image fusion, performance analysis is important since the evaluation result gives valuable information which can be utilized in various applications, such as military, medical imaging, remote sensing, and so on. In this paper, we analyze and compare the performance of fusion methods based on four different transforms: i) wavelet transform, ii) curvelet transform, iii) contourlet transform and iv) nonsubsampled contourlet transform. Fusion framework and scheme are explained in detail, and two different sets of images are used in our experiments. Furthermore, various performance evaluation metrics are adopted to quantitatively analyze the fusion results. The comparison results show that the nonsubsampled contourlet transform method performs better than the other three methods. During the experiments, we also found out that the decomposition level of 3 showed the best fusion performance, and decomposition levels beyond level-3 did not significantly affect the fusion results.
Gray John C
2006-11-01
Full Text Available Abstract Background The floral dip method of transformation by immersion of inflorescences in a suspension of Agrobacterium is the method of choice for Arabidopsis transformation. The presence of a marker, usually antibiotic- or herbicide-resistance, allows identification of transformed seedlings from untransformed seedlings. Seedling selection is a lengthy process which does not always lead to easily identifiable transformants. Selection for kanamycin-, phosphinothricin- and hygromycin B-resistance commonly takes 7–10 d and high seedling density and fungal contamination may result in failure to recover transformants. Results A method for identifying transformed seedlings in as little as 3.25 d has been developed. Arabidopsis T1 seeds obtained after floral dip transformation are plated on 1% agar containing MS medium and kanamycin, phosphinothricin or hygromycin B, as appropriate. After a 2-d stratification period, seeds are subjected to a regime of 4–6 h light, 48 h dark and 24 h light (3.25 d. Kanamycin-resistant and phosphinothricin-resistant seedlings are easily distinguished from non-resistant seedlings by green expanded cotyledons whereas non-resistant seedlings have pale unexpanded cotyledons. Seedlings grown on hygromycin B differ from those grown on kanamycin and phosphinothricin as both resistant and non-resistant seedlings are green. However, hygromycin B-resistant seedlings are easily identified as they have long hypocotyls (0.8–1.0 cm whereas non-resistant seedlings have short hypocotyls (0.2–0.4 cm. Conclusion The method presented here is an improvement on current selection methods as it allows quicker identification of transformed seedlings: transformed seedlings are easily discernable from non-transformants in as little as 3.25 d in comparison to the 7–10 d required for selection using current protocols.
Transformer winding defects identification based on a high frequency method
Florkowski, Marek; Furgał, Jakub
2007-09-01
The transformer diagnostic methods are systematically being improved and extended due to growing requirements for reliability of power systems in terms of uninterrupted power supply and avoidance of blackouts. Those methods are also driven by longer lifetime of transformers and demand for reduction of transmission and distribution costs. Hence, the detection of winding faults in transformers, both in exploitation or during transportation is an important aspect of power transformer failure prevention. The frequency response analysis method (FRA), more and more frequently used in electric power engineering, has been applied for investigations and signature analysis based on the admittance and transfer function. The paper presents a novel approach to the identification of typical transformer winding problems such as axial or radial movements or turn-to-turn faults. The proposed transfer function discrimination (TFD) criteria are based on the derived transfer function ratios, manifesting higher sensitivity.
Hough transform method for track finding in center drift chamber
Azmi, K. A. Mohammad Kamal; Wan Abdullah, W. A. T.; Ibrahim, Zainol Abidin
2016-01-01
Hough transform is a global tracking method used which had been expected to be faster approach for tracking the circular pattern of electron moving in Center Drift Chamber (CDC), by transforming the point of hit into a circular curve. This paper present the implementation of hough transform method for the reconstruction of tracks in Center Drift Chamber (CDC) which have been generated by random number in C language programming. Result from implementation of this method shows higher peak of circle parameter value (xc,yc,rc) that indicate the similarity value of the parameter needed for circular track in CDC for charged particles in the region of CDC.
Hough transform method for track finding in center drift chamber
Azmi, K. A. Mohammad Kamal, E-mail: khasmidatul@siswa.um.edu.my; Wan Abdullah, W. A. T., E-mail: wat@um.edu.my; Ibrahim, Zainol Abidin [National Centre for Particle Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)
2016-01-22
Hough transform is a global tracking method used which had been expected to be faster approach for tracking the circular pattern of electron moving in Center Drift Chamber (CDC), by transforming the point of hit into a circular curve. This paper present the implementation of hough transform method for the reconstruction of tracks in Center Drift Chamber (CDC) which have been generated by random number in C language programming. Result from implementation of this method shows higher peak of circle parameter value (xc,yc,rc) that indicate the similarity value of the parameter needed for circular track in CDC for charged particles in the region of CDC.
Hough transform method for track finding in center drift chamber
Hough transform is a global tracking method used which had been expected to be faster approach for tracking the circular pattern of electron moving in Center Drift Chamber (CDC), by transforming the point of hit into a circular curve. This paper present the implementation of hough transform method for the reconstruction of tracks in Center Drift Chamber (CDC) which have been generated by random number in C language programming. Result from implementation of this method shows higher peak of circle parameter value (xc,yc,rc) that indicate the similarity value of the parameter needed for circular track in CDC for charged particles in the region of CDC
Direct Linear Transformation Method for Three-Dimensional Cinematography
Shapiro, Robert
1978-01-01
The ability of Direct Linear Transformation Method for three-dimensional cinematography to locate points in space was shown to meet the accuracy requirements associated with research on human movement. (JD)
Transformation methods for nonlinear partial differential equations
Edelen, Dominic GB
1992-01-01
The purpose of the book is to provide research workers in applied mathematics, physics, and engineering with practical geometric methods for solving systems of nonlinear partial differential equations. The first two chapters provide an introduction to the more or less classical results of Lie dealing with symmetries and similarity solutions. The results, however, are presented in the context of contact manifolds rather than the usual jet bundle formulation and provide a number of new conclusions. The remaining three chapters present essentially new methods of solution that are based on recent
Cell Phones Transform a Science Methods Course
Madden, Lauren
2012-01-01
A science methods instructor intentionally encouraged cell phone use for class work to discover how cell phones can be used as research tools to enhance the content and engage the students. The anecdotal evidence suggested that students who used their smartphones as research tools experienced the science content and pedagogical information…
Method for online measurement of optical current transformer onsite errors
This paper describes a method for the online measurement of an optical current transformer (OCT) onsite errors comparing with a conventional electromagnetic current transformer (CT) as the reference transformer. The OCT under measurement is connected in series with the reference electromagnetic CT in the same line bay. The secondary output signals of the OCT and the electromagnetic CT are simultaneously collected and processed using a digital signal processing technique. The tests developed on a prototype clearly indicate that the method is very suitable for measuring errors of the OCT onsite without an interruption in the service. The onsite error characteristics of the OCT are analyzed, as well as the stability and repeatability. (paper)
A method for encapsulating high voltage power transformers
Sanchez, Robert O.
Voltage breakdowns become a major concern in reducing the size of high-voltage power converter transformers. Even the smallest of voids can provide a path for corona discharge which can cause a dielectric breakdown leading to a transformer failure. A method of encapsulating small high voltage transformers has been developed. The method virtually eliminates voids in the impregnation material, provides an exceptional dielectric between windings and provides a mechanically rugged package. The encapsulation material is a carboxyl terminated butadiene nitril (CTBN) modified mica filled epoxy. The method requires heat/vacuum to impregnate the coil and heat/pressure to cure the encapsulant. The transformer package utilizes a diallyl phthalate (DAP) contact assembly in which a coated core/coil assembly is mounted and soldered. This assembly is then loaded into an RTV mold and the encapsulation process begins.
A Secret Image Sharing Method Using Integer Wavelet Transform
Li Ching-Chung
2007-01-01
Full Text Available A new image sharing method, based on the reversible integer-to-integer (ITI wavelet transform and Shamir's threshold scheme is presented, that provides highly compact shadows for real-time progressive transmission. This method, working in the wavelet domain, processes the transform coefficients in each subband, divides each of the resulting combination coefficients into shadows, and allows recovery of the complete secret image by using any or more shadows . We take advantages of properties of the wavelet transform multiresolution representation, such as coefficient magnitude decay and excellent energy compaction, to design combination procedures for the transform coefficients and processing sequences in wavelet subbands such that small shadows for real-time progressive transmission are obtained. Experimental results demonstrate that the proposed method yields small shadow images and has the capabilities of real-time progressive transmission and perfect reconstruction of secret images.
Analytical method for space-fractional telegraph equation by homotopy perturbation transform method
Prakash, Amit
2016-06-01
The object of the present article is to study spacefractional telegraph equation by fractional Homotopy perturbation transform method (FHPTM). The homotopy perturbation transform method is an innovative adjustment in Laplace transform algorithm. Three test examples are presented to show the efficiency of the proposed technique.
A New Method of Improving Transformer Restricted Earth Fault Protection
KRSTIVOJEVIC, J. P.
2014-08-01
Full Text Available A new method of avoiding malfunctioning of the transformer restricted earth fault (REF protection is presented. Application of the proposed method would eliminate unnecessary operation of REF protection in the cases of faults outside protected zone of a transformer or a magnetizing inrush accompanied by current transformer (CT saturation. On the basis of laboratory measurements and simulations the paper presents a detailed performance assessment of the proposed method which is based on digital phase comparator. The obtained results show that the new method was stable and precise for all tested faults and that its application would allow making a clear and precise difference between an internal fault and: (i external fault or (ii magnetizing inrush. The proposed method would improve performance of REF protection and reduce probability of maloperation due to CT saturation. The new method is robust and characterized by high speed of operation and high reliability and security.
Transforming han: a correlational method for psychology and religion.
Oh, Whachul
2015-06-01
Han is a destructive feeling in Korea. Although Korea accomplished significant exterior growth, Korean society is still experiencing the dark aspects of transforming han as evidenced by having the highest suicide rate in Asia. Some reasons for this may be the fragmentation between North and South Korea. If we can transform han then it can become constructive. I was challenged to think of possibilities for transforming han internally; this brings me to the correlational method through psychological and religious interpretation. This study is to challenge and encourage many han-ridden people in Korean society. Through the psychological and religious understanding of han, people suffering can positively transform their han. They can relate to han more subjectively, and this means the han-ridden psyche has an innate sacredness of potential to transform. PMID:25252804
Transformation of Morinda citrifolia via simple mature seed imbibition method.
Lee, J J; Ahmad, S; Roslan, H A
2013-12-15
Morinda citrifolia, is a valuable medicinal plant with a wide range of therapeutic properties and extensive transformation study on this plant has yet been known. Present study was conducted to establish a simple and reliable transformation protocol for M. citrifolia utilising Agrobacterium tumefaciens via direct seed exposure. In this study, the seeds were processed by tips clipping and dried and subsequently incubated in inoculation medium. Four different parameters during the incubation such as incubation period, bacterial density, temperature and binary vectors harbouring beta-glucuronidase (GUS) gene (pBI121 and pGSA1131), were tested to examine its effect on transformation efficiency. The leaves from the treated and germinated seedlings were analysed via Polymerase Chain Reaction (PCR), histochemical assay of the GUS gene and reverse transcription-PCR (RT-PCR). Results of the study showed that Agrobacterium strain LBA4404 with optical density of 1.0 and 2 h incubation period were optimum for M. citrifolia transformation. It was found that various co-cultivation temperatures tested and type of vector used did not affect the transformation efficiency. The highest transformation efficiency for M. citrifolia direct seed transformation harbouring pBI121 and pGSA1131 was determined to be 96.8% with 2 h co-cultivation treatment and 80.4% when using bacterial density of 1.0, respectively. The transformation method can be applied for future characterization study of M. citrifolia. PMID:24517006
Solving SAT by Algorithm Transform of Wu‘s Method
贺思敏; 张钹
1999-01-01
Recently algorithms for solving propositional satisfiability problem, or SAT,have aroused great interest,and more attention has been paid to transformation problem solving.The commonly used transformation is representation transform,but since its intermediate computing procedure is a black box from the viewpoint of the original problem,this approach has many limitations.In this paper,a new approach called algorithm transform is proposed and applied to solving SAT by Wu's method,a general algorithm for solving polynomial equations.B y establishing the correspondence between the primitive operation in Wu's method and clause resolution is SAT,it is shown that Wu's method,when used for solving SAT,,is primarily a restricted clause resolution procedure.While Wu's method introduces entirely new concepts.e.g.characteristic set of clauses,to resolution procedure,the complexity result of resolution procedure suggests an exponential lower bound to Wu's method for solving general polynomial equations.Moreover,this algorithm transform can help achieve a more efficient implementation of Wu's method since it can avoid the complex manipulation of polynomials and can make the best use of domain specific knowledge.
Spatial Fourier transform method for evaluating SQUID gradiometers
A simple method of measuring the spatial transfer function of a gradiometer, consisting of a flux transformer coupled to a SQUID, is presented and it is compared with theoretical predictions. Based, on this approach, a new method of reporting a gradiometer's performance is proposed; the rejection factor is expressed in decibels obtained directly from the transfer function plot
Back-transformation of treatment differences - an approximate method
Laursen, Rikke Pilmann; Dalskov, Stine-Mathilde; Damsgaard, Camilla Trab; Ritz, Christian
2014-01-01
-transformed estimated differences, and corresponding standard errors and 95% confidence intervals.Subjects/Methods:Based on data from two randomized controlled studies and an exemplary data set that had all previously been published, we evaluated our approximate procedure by comparing results for different approaches......Background/Objectives:Transformation of outcomes is frequently used in the analysis of studies in clinical nutrition. However, back-transformation of estimated treatment means and differences is complicated by the nonlinear nature of the transformations. It is not straightforward to obtain an...... estimated treatment difference that can be interpreted without any reference to the additional predictors included in the statistical model; and moreover, standard errors are not easily available. The aim of this work was to provide a generally applicable, yet operational procedure for obtaining back...
Transforming Mean and Osculating Elements Using Numerical Methods
Ely, Todd A.
2015-03-01
Mean element propagation of perturbed two body orbits has as its mathematical basis the averaging theory of nonlinear dynamical systems. Mean elements define an orbit's long-term evolution characteristics consisting of both secular and long-period effects. Using averaging theory, a near-identity transformation can be found that transforms between the mean elements and their osculating counterparts that augment the mean elements with short period effects. The ability to perform the conversion is necessary so that orbit design conducted in either mean elements or osculating can be effectively converted between each element type. In the present work, the near-identity transformation is found using the Fast Fourier Transform. An efficient method is found that is capable of recovering the mean or osculating elements to first-order.
Multifractional Fourier Transform Method and Its Applications to Image Encryption
RANQiwen; WANGQi; MAJing; TANLiying
2003-01-01
The multiplicity of the fractional Fourier transform(FRFT),which is intrinsic in any fractional operator,has been claimed by several authors,but never across-the-board developed.Particularly,the weight-type FRFT(WFRFT) has not been investigated.Starting with defining the multifractional Fourier transform (MFRFT),we gained the generalization permutation matrix group (GPMG)representation and multiplicity of the MFRFT,and the relationships among the MFRFT the standard WFRFT and the standard CFRFT.Finally,as a application,a novel image encryption method hased on the MFRFT is propounded.Similation results show that this method is safe,practicable and impactful.
Fourier transform method for evaluation resonance interaction effects
Resonance interaction effects are treated by the Fourier transform method. For the case of two interfering resonances, the slowing-down equation with temperature-dependent cross-sections is transformed to two coupled Fredholm integral equations. In the limit of zero temperature, it is shown that they reduce to coupled second order differential equations and are treated accurately by the WKB method. Temperature-dependent contributions to the resonance integrals are obtained from the solution of the integral equations using Gauss-Hermite quadrature formulae. Numerical results are presented for two interfering low-energy resonances of thorium 232. (orig.)
Novitsky, Andrey [Department of Theoretical Physics, Belarusian State University, Nezavisimosti Avenue 4, 220050 Minsk (Belarus); Qiu, C-W [Research Laboratory of Electronics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Zouhdi, Said [Laboratoire de Genie Electrique de Paris, SUPELEC, Plateau de Moulon 91192, Gif-sur-Yvette (France)], E-mail: eleqc@nus.edu.sg
2009-11-15
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.
Modified Differential Transform Method for Two Singular Boundary Values Problems
Yinwei Lin
2014-01-01
Full Text Available This paper deals with the two singular boundary values problems of second order. Two singular points are both boundary values points of the differential equation. The numerical solutions are developed by modified differential transform method (DTM for expanded point. Linear and nonlinear models are solved by this method to get more reliable and efficient numerical results. It can also solve ordinary differential equations where the traditional one fails. Besides, we give the convergence of this new method.
Application of laplace transform method in heavy ion reaction research
Laplace transform method (LTM) is applied to investigate the effects of different spectroscopy amplifiers parameters on identification of the light charged particles (LCP) emitted from 12C(46,7 MeV/u) + 58Ni reaction. The significance of application of LTM in heavy ion experimental nuclear physics is also discussed
Differential Transformation Method for Temperature Distribution in a Radiating Fin
Rahimi, M.; Hosseini, M. J.; Barari, Amin;
2011-01-01
Radiating extended surfaces are widely used to enhance heat transfer between a primary surface and the environment. In this paper, the differential transformation method (DTM) is proposed for solving nonlinear differential equation of temperature distribution in a heat radiating fin. The concept of...
Equidistribution for meromorphic transforms and the ddc-method
Tien-Cuong Dinh; Nessim Sibony
2005-01-01
In this paper we give an introduction to the notion of meromorphic transform.We describe some equidistribution problems and their solution, using the ddc-method. In particular, we give some statistical properties of the equilibrium measure for meromorphic maps on compact Kahler manifolds: K-mixing, exponential decay of correlations and central limit theorem.
Approximate method for controlling solid elastic waves by transformation media
Hu, Jin; Chang, Zheng; Hu, Gengkai
2011-11-01
By idealizing a general mapping as a series of local affine ones, we derive approximately transformed material parameters necessary to control solid elastic waves within classical elasticity theory. The transformed elastic moduli are symmetric, and can be used with Navier's equation to manipulate elastic waves. It is shown numerically that the method can provide a powerful tool to control elastic waves in solids in case of high frequency or small material gradient. Potential applications can be anticipated in nondestructive testing, structure impact protection, petroleum exploration, and seismology.
Process identification method based on the Z transformation
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)
Wavelet Transform based Medical Image Fusion With different fusion methods
Anjali Patil
2015-03-01
Full Text Available This paper proposes wavelet transform based image fusion algorithm, after studying the principles and characteristics of the discrete wavelet transform. Medical image fusion used to derive useful information from multimodality medical images. The idea is to improve the image content by fusing images like computer tomography (CT and magnetic resonance imaging (MRI images, so as to provide more information to the doctor and clinical treatment planning system. This paper based on the wavelet transformation to fused the medical images. The wavelet based fusion algorithms used on medical images CT and MRI, This involve the fusion with MIN , MAX, MEAN method. Also the result is obtained. With more available multimodality medical images in clinical applications, the idea of combining images from different modalities become very important and medical image fusion has emerged as a new promising research field
A dynamic integrated fault diagnosis method for power transformers.
Gao, Wensheng; Bai, Cuifen; Liu, Tong
2015-01-01
In order to diagnose transformer fault efficiently and accurately, a dynamic integrated fault diagnosis method based on Bayesian network is proposed in this paper. First, an integrated fault diagnosis model is established based on the causal relationship among abnormal working conditions, failure modes, and failure symptoms of transformers, aimed at obtaining the most possible failure mode. And then considering the evidence input into the diagnosis model is gradually acquired and the fault diagnosis process in reality is multistep, a dynamic fault diagnosis mechanism is proposed based on the integrated fault diagnosis model. Different from the existing one-step diagnosis mechanism, it includes a multistep evidence-selection process, which gives the most effective diagnostic test to be performed in next step. Therefore, it can reduce unnecessary diagnostic tests and improve the accuracy and efficiency of diagnosis. Finally, the dynamic integrated fault diagnosis method is applied to actual cases, and the validity of this method is verified. PMID:25685841
Image Watermarking Method Using Integer-to-Integer Wavelet Transforms
陈韬; 王京春
2002-01-01
Digital watermarking is an efficient method for copyright protection for text, image, audio, and video data. This paper presents a new image watermarking method based on integer-to-integer wavelet transforms. The watermark is embedded in the significant wavelet coefficients by a simple exclusive OR operation. The method avoids complicated computations and high computer memory requirements that are the main drawbacks of common frequency domain based watermarking algorithms. Simulation results show that the embedded watermark is perceptually invisible and robust to various operations, such as low quality joint picture expert group (JPEG) compression, random and Gaussian noises, and smoothing (mean filtering).
Unitary transformation method for solving generalized Jaynes-Cummings models
Sudha Singh
2006-03-01
Two fully quantized generalized Jaynes-Cummings models for the interaction of a two-level atom with radiation field are treated, one involving intensity dependent coupling and the other involving multiphoton interaction between the field and the atom. The unitary transformation method presented here not only solves the time dependent problem but also allows a determination of the eigensolutions of the interacting Hamiltonian at the same time.
Electrocardiogram ST-Segment Morphology Delineation Method Using Orthogonal Transformations
Miha Amon; Franc Jager
2016-01-01
Differentiation between ischaemic and non-ischaemic transient ST segment events of long term ambulatory electrocardiograms is a persisting weakness in present ischaemia detection systems. Traditional ST segment level measuring is not a sufficiently precise technique due to the single point of measurement and severe noise which is often present. We developed a robust noise resistant orthogonal-transformation based delineation method, which allows tracing the shape of transient ST segment morph...
Multi-band Image Registration Method Based on Fourier Transform
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.
Electrocardiogram ST-Segment Morphology Delineation Method Using Orthogonal Transformations.
Amon, Miha; Jager, Franc
2016-01-01
Differentiation between ischaemic and non-ischaemic transient ST segment events of long term ambulatory electrocardiograms is a persisting weakness in present ischaemia detection systems. Traditional ST segment level measuring is not a sufficiently precise technique due to the single point of measurement and severe noise which is often present. We developed a robust noise resistant orthogonal-transformation based delineation method, which allows tracing the shape of transient ST segment morphology changes from the entire ST segment in terms of diagnostic and morphologic feature-vector time series, and also allows further analysis. For these purposes, we developed a new Legendre Polynomials based Transformation (LPT) of ST segment. Its basis functions have similar shapes to typical transient changes of ST segment morphology categories during myocardial ischaemia (level, slope and scooping), thus providing direct insight into the types of time domain morphology changes through the LPT feature-vector space. We also generated new Karhunen and Lo ève Transformation (KLT) ST segment basis functions using a robust covariance matrix constructed from the ST segment pattern vectors derived from the Long Term ST Database (LTST DB). As for the delineation of significant transient ischaemic and non-ischaemic ST segment episodes, we present a study on the representation of transient ST segment morphology categories, and an evaluation study on the classification power of the KLT- and LPT-based feature vectors to classify between ischaemic and non-ischaemic ST segment episodes of the LTST DB. Classification accuracy using the KLT and LPT feature vectors was 90% and 82%, respectively, when using the k-Nearest Neighbors (k = 3) classifier and 10-fold cross-validation. New sets of feature-vector time series for both transformations were derived for the records of the LTST DB which is freely available on the PhysioNet website and were contributed to the LTST DB. The KLT and LPT
Electrocardiogram ST-Segment Morphology Delineation Method Using Orthogonal Transformations.
Miha Amon
Full Text Available Differentiation between ischaemic and non-ischaemic transient ST segment events of long term ambulatory electrocardiograms is a persisting weakness in present ischaemia detection systems. Traditional ST segment level measuring is not a sufficiently precise technique due to the single point of measurement and severe noise which is often present. We developed a robust noise resistant orthogonal-transformation based delineation method, which allows tracing the shape of transient ST segment morphology changes from the entire ST segment in terms of diagnostic and morphologic feature-vector time series, and also allows further analysis. For these purposes, we developed a new Legendre Polynomials based Transformation (LPT of ST segment. Its basis functions have similar shapes to typical transient changes of ST segment morphology categories during myocardial ischaemia (level, slope and scooping, thus providing direct insight into the types of time domain morphology changes through the LPT feature-vector space. We also generated new Karhunen and Lo ève Transformation (KLT ST segment basis functions using a robust covariance matrix constructed from the ST segment pattern vectors derived from the Long Term ST Database (LTST DB. As for the delineation of significant transient ischaemic and non-ischaemic ST segment episodes, we present a study on the representation of transient ST segment morphology categories, and an evaluation study on the classification power of the KLT- and LPT-based feature vectors to classify between ischaemic and non-ischaemic ST segment episodes of the LTST DB. Classification accuracy using the KLT and LPT feature vectors was 90% and 82%, respectively, when using the k-Nearest Neighbors (k = 3 classifier and 10-fold cross-validation. New sets of feature-vector time series for both transformations were derived for the records of the LTST DB which is freely available on the PhysioNet website and were contributed to the LTST DB. The
Mikulović Jovan Č.
2014-01-01
Full Text Available A methodology for calculation of overvoltages in transformer windings, based on a numerical method of inverse Laplace transform, is presented. Mathematical model of transformer windings is described by partial differential equations corresponding to distributed parameters electrical circuits. The procedure of calculating overvoltages is applied to windings having either isolated neutral point, or grounded neutral point, or neutral point grounded through impedance. A comparative analysis of the calculation results obtained by the proposed numerical method and by analytical method of calculation of overvoltages in transformer windings is presented. The results computed by the proposed method and measured voltage distributions, when a voltage surge is applied to a three-phase 30 kVA power transformer, are compared. [Projekat Ministartsva nauke Republike Srbije, br. TR-33037 i br. TR-33020
Syed Tauseef Mohyud-Din
2015-01-01
Full Text Available This paper witnesses the coupling of an analytical series expansion method which is called reduced differential transform with fractional complex transform. The proposed technique is applied on three mathematical models, namely, fractional Kaup-Kupershmidt equation, generalized fractional Drinfeld-Sokolov equations, and system of coupled fractional Sine-Gordon equations subject to the appropriate initial conditions which arise frequently in mathematical physics. The derivatives are defined in Jumarie’s sense. The accuracy, efficiency, and convergence of the proposed technique are demonstrated through the numerical examples. It is observed that the presented coupling is an alternative approach to overcome the demerit of complex calculation of fractional differential equations. The proposed technique is independent of complexities arising in the calculation of Lagrange multipliers, Adomian’s polynomials, linearization, discretization, perturbation, and unrealistic assumptions and hence gives the solution in the form of convergent power series with elegantly computed components. All the examples show that the proposed combination is a powerful mathematical tool to solve other nonlinear equations also.
Zoom synchrosqueezing transform and iterative demodulation: Methods with application
Cao, Hongrui; Xi, Songtao; Chen, Xuefeng; Wang, Shibin
2016-05-01
Synchrosqueezing is a powerful time-frequency analysis tool for signals with time-varying frequency. However, as it is based on the continuous wavelet transform, its time-frequency representation (TFR) has better time but worse frequency resolution in higher frequency region, while worse time but better frequency resolution in lower frequency region. It makes the synchrosqueezing difficult to accurately estimate IFs with highly oscillating rate but small fluctuation amplitude. To address this issue, a zoom synchrosqueezing transform (ZST) is proposed to generate both excellent time and frequency resolution in a specific frequency region and analyze the mono-component signal in the particular frequency region to obtain accurate IF estimation results. For multi-component signals with nonlinear and close IFs, a ZST based dual iterative demodulation method is proposed, with the inner iteration to gradually refine and accurately extract a concerned mono-component, and the outer iteration to extract all mono-components gradually to alleviate the interference between individual components. Then satisfactory energy concentrated TFRs and accurate IF estimation results of mono-components can be obtained by the proposed ZST. The TFR of the multi-component signal can be gained by superposing the TFRs of all mono-components. The effectiveness of the proposed methods was validated using both simulated signals and a rub-impact signal collected from an engineering machine unit.
Transformational Teaching: Theoretical Underpinnings, Basic Principles, and Core Methods
Slavich, George M.; Zimbardo, Philip G.
2012-01-01
Approaches to classroom instruction have evolved considerably over the past 50 years. This progress has been spurred by the development of several learning principles and methods of instruction, including active learning, student-centered learning, collaborative learning, experiential learning, and problem-based learning. In the present paper, we suggest that these seemingly different strategies share important underlying characteristics and can be viewed as complimentary components of a broader approach to classroom instruction called transformational teaching. Transformational teaching involves creating dynamic relationships between teachers, students, and a shared body of knowledge to promote student learning and personal growth. From this perspective, instructors are intellectual coaches who create teams of students who collaborate with each other and with their teacher to master bodies of information. Teachers assume the traditional role of facilitating students’ acquisition of key course concepts, but do so while enhancing students’ personal development and attitudes toward learning. They accomplish these goals by establishing a shared vision for a course, providing modeling and mastery experiences, challenging and encouraging students, personalizing attention and feedback, creating experiential lessons that transcend the boundaries of the classroom, and promoting ample opportunities for preflection and reflection. We propose that these methods are synergistically related and, when used together, maximize students’ potential for intellectual and personal growth. PMID:23162369
Linear transformation method to control flexural waves in thin plates.
Liu, Yongquan; Ma, Zhaoyang; Su, Xianyue
2016-08-01
In this paper, the linear transformation method (LTM) to control flexural waves propagating in thin plates is presented. Unlike earlier studies, only a small number of homogeneous materials with no requirement of in-plane forces or pre-stress are needed, which tremendously simplifies the implementation of devices for flexural waves. An invisibility cloak with homogeneous materials is studied to confirm the validity of the present approach, and to show its imperfection due to impedance mismatch at interfaces. Required materials can be further simplified as layered isotropic materials using the effective medium theory. Finally, the LTM can be extended to the case of flexural waves propagating in anisotropic thin plates. The present method opens a promising avenue toward the realization of advanced structured shields and other devices. PMID:27586744
M. Rasoulpoor
2013-09-01
Full Text Available This paper presents a new approach for power transformer differential protection. The Wavelet Transform is applied to discriminate between inrush currents and internal fault currents in power transformers. Discrete wavelet transform decomposes the current signal into sub-bands that give more information about the properties of the signals in different frequency bands. Also, this transform is used to investigate the energy distribution of the signal on the different time and frequency scales. Recognition method is based on the correlation factors between energy percentage vectors of the Wavelet coefficients. Discrete Wavelet transform is used for decomposing the current signals to different frequency coefficients. After that, by constituting the energy percentage vectors of wavelet transform coefficients and calculating the correlation factors between these vectors, it is possible to form a recognition criterion to distinguish between inrush and internal fault current in the proposed method. The proposed algorithm is tested for several conditions by simulated inrush and internal fault currents. Simulation of current signals is performed using electromagnetic transient program PSCAD/EMTDC software that is a powerful program for the investigation of transient signals. Simulation results show that the proposed scheme accurately identifies inrush and fault currents in the distance of the power transformer protection in less than quarter of power frequency cycle. Also, beside the sensitivity and high reliability, the proposed method has low computation content and unlike the common methods does not require to determine the threshold for each new power system.
Replicon sizes were measured in Simian Virus 40 (SV40)-transformed and untransformed normal human, xeroderma pigmentosum (XP), and mouse 3T3 cells with an x-ray plus bromodeoxyuridine (BUdR) photolysis method. Replicon sizes in SV40-transformed cells were at least twice those in untransformed counterparts, but DNA fork displacement rates were only slightly increased
Peters, Terri
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....
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).
In this paper, we will compare the differential transformation method DTM and Adomian decomposition method ADM to solve partial differential equations (PDEs). The definition and operations of differential transform method was introduced by Zhou [Zhou JK. Differential transformation and its application for electrical circuits. Wuuhahn, China: Huarjung University Press; 1986 [in Chinese
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.
Dressing transformation method for finding soliton solutions of the sinh-Gordon equation
In this paper, the establishment of the dressing transformations in the sinh-Gordon model is reconsidered. By carefully analysing the infinitesimal structures of dressing transformations, we improve the algebraic method for solving the dressing problem in the system and then lay the dressing transformation method on a firm basis. The modified dressing transformation method, which no longer contains any deductive jumps, turns out to become a powerful Hamiltonian approach to finding N-soliton solutions (N≥1) of the integrable systems. (author)
Contourlet Transform Based Method For Medical Image Denoising
Abbas H. Hassin AlAsadi
2015-02-01
Full Text Available Noise is an important factor of the medical image quality, because the high noise of medical imaging will not give us the useful information of the medical diagnosis. Basically, medical diagnosis is based on normal or abnormal information provided diagnose conclusion. In this paper, we proposed a denoising algorithm based on Contourlet transform for medical images. Contourlet transform is an extension of the wavelet transform in two dimensions using the multiscale and directional filter banks. The Contourlet transform has the advantages of multiscale and time-frequency-localization properties of wavelets, but also provides a high degree of directionality. For verifying the denoising performance of the Contourlet transform, two kinds of noise are added into our samples; Gaussian noise and speckle noise. Soft thresholding value for the Contourlet coefficients of noisy image is computed. Finally, the experimental results of proposed algorithm are compared with the results of wavelet transform. We found that the proposed algorithm has achieved acceptable results compared with those achieved by wavelet transform.
Transformation Methods for Using Combination of Remotely Sensed Data and Cadastral Maps
Dönmez, Ş. Ö.; Tunc, A.
2016-06-01
In order to examine using cadastral maps as base maps for aerial orthophotos, two different 2D transformation methods were applied between various coordinate systems. Study area was chosen from Kagithane district in Istanbul. The used data is an orthophoto (30 cm spatial resolution), and cadastral map (1:1000) taken from land office, containing the same region. Transformation methods are chosen as; 1st Order Polynomial Transformation and Helmert 2D Transformation within this study. The test points, used to determine the coefficients between the datums, were 26 common traverse points and the check points, used to compare the transformed coordinates to reliable true coordinates, were 10 common block corners. The transformation methods were applied using Matlab software. After applying the methods, residuals were calculated and compared between each transformation method in order to use cadastral maps as reliable vector data.
Wavelet Transform based Medical Image Fusion With different fusion methods
Anjali Patil; M. N. Tibdewal
2015-01-01
This paper proposes wavelet transform based image fusion algorithm, after studying the principles and characteristics of the discrete wavelet transform. Medical image fusion used to derive useful information from multimodality medical images. The idea is to improve the image content by fusing images like computer tomography (CT) and magnetic resonance imaging (MRI) images, so as to provide more information to the doctor and clinical treatment planning system. This paper based on t...
Methods of Weyl representation of the phase space and canonical transformations
The author studies nonlinear canonical transformations realized in the space of Weyl symbols of quantum operators. The kernels of the transformations, the symbol of the intertwining operator of the group of inhomogeneous point transformations, an the group characters are constructed. The group of PL transformations, which is the free produce of the group of point, p, and linear, L, transformations is considered. The simplest PL complexes relating problems with different potentials, in particular, containing a general Darboux transformation of the factorization method, are constructed. The kernel of an arbitrary element of the group PL is found
Transformation Matrix for Time Discretization Based on Tustin’s Method
Yiming Jiang
2014-01-01
Full Text Available This paper studies rules in transformation of transfer function through time discretization. A method of using transformation matrix to realize bilinear transform (also known as Tustin’s method is presented. This method can be described as the conversion between the coefficients of transfer functions, which are expressed as transform by certain matrix. For a polynomial of degree n, the corresponding transformation matrix of order n exists and is unique. Furthermore, the transformation matrix can be decomposed into an upper triangular matrix multiplied with another lower triangular matrix. And both have obvious regularity. The proposed method can achieve rapid bilinear transform used in automatic design of digital filter. The result of numerical simulation verifies the correctness of the theoretical results. Moreover, it also can be extended to other similar problems. Example in the last throws light on this point.
A new method for classification of Brachiopods based on the radon transformation
Youssef Ait khouya
2011-09-01
Full Text Available Brachiopods have a lateral outline which is quite important in systematic studies. It is often assessed by a qualitative evaluation and linear measurements, which are not clear enough and precise for describing the shape of the shell and its changes In this paper we propose a new method for classification of fossils based on the radon transform from their greyscale image. We take the case of brachiopods which has Complex shapes. We use an adaptation of Radon transform called R-transform which is invariant to common geometrical transformations. Each shape is described by R3D transform. We consider the grayscale image as a set of cuts obtained from successive binarization for each gray level in image, and for each segmentation we compute the R-transform then we obtained the R3D transform. The advantages of the proposed method are robustness to noise, and invariant to common geometrical transformations scale, translation and rotation.
Methods of weyl representation of the phase space and canonical transformations
The author finds the structure of the kernel of a canonical transformation and a differential equation for the symbol of the intertwining operator. The symbol of a general linear canonical transformation is constructed in terms of a Cayley transformation of the symplectic transformation of the phase space. Its singularities and applications to group theory are studied. The Green's functions and spectral projectors of arbitrary quadratic systems are constructed using the classification methods of classical mechanics
A Simplified Seed Transformation Method for Obtaining Transgenic Brassica napus Plants
SONG Li; ZHAO De-gang; WU Yong-jun; TIAN Xiao-e
2009-01-01
We report here a seed transformation of sonication-assisted,no-tissue culture to rapidly produce transgenic Brassica napus plants.This method comprises the steps of treating seeds by ultrasonic wave,inoculating Agrobacterium tumefaciens with a recombinant ChlFN-a gene and germinating directly of treatment seed on wet filter papers.The obtained transformants were verified by GUS histochemical assay and nested PCR amplification.It suggests that seed transformation has a potential use in genetic transformation of rape.
Murat Osmanoglu
2013-01-01
Full Text Available We have considered linear partial differential algebraic equations (LPDAEs of the form , which has at least one singular matrix of . We have first introduced a uniform differential time index and a differential space index. The initial conditions and boundary conditions of the given system cannot be prescribed for all components of the solution vector here. To overcome this, we introduced these indexes. Furthermore, differential transform method has been given to solve LPDAEs. We have applied this method to a test problem, and numerical solution of the problem has been compared with analytical solution.
Fourier transformation methods in the field of gamma spectrometry
A Abdel-Hafiez
2006-09-01
The basic principles of a new version of Fourier transformation is presented. This new version was applied to solve some main problems such as smoothing, and denoising in gamma spectroscopy. The mathematical procedures were first tested by simulated data and then by actual experimental data.
Radiation method of sulfide compound transformation in petroleum products
Processes of sulphuric compounds transformation for petroleum and heavy residuals under radiation and thermal treatment action are studied. It is shown that sulphuric compounds are concentrated in heavy fractions as a result of radiation processing. Heavy petroleum products irradiation provokes considerable decrease in the content of mercaptans, disulphides and sulphides, which transfer to sulphoxides and sulphones appearing during radiation-induced oxidation process. (author)
M. Rasoulpoor; M. Banejad; Ahmadyfard, A
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 ...
Exact Foldy-Wouthuysen transformation of the Dirac-Pauli Hamiltonian by Kutzelnigg's method
Chiou, Dah-Wei; Chen, Tsung-Wei
2014-01-01
We apply Kutzelnigg's method for the Foldy-Wouthuysen (FW) transformation upon the Dirac-Pauli Hamiltonian. The exact FW transformations exist and agree with those obtained by Eriksen's method for two special cases. In the weak-field limit of static and homogeneous electromagnetic fields, the long-held speculation is rigorously proven, by mathematical induction on the orders of $1/c$ in the power series, that the FW transformed Dirac-Pauli Hamiltonian is in full agreement with the classical c...
Apparatus and methods for continuous beam fourier transform mass spectrometry
McLuckey, Scott A.; Goeringer, Douglas E.
2002-01-01
A continuous beam Fourier transform mass spectrometer in which a sample of ions to be analyzed is trapped in a trapping field, and the ions in the range of the mass-to-charge ratios to be analyzed are excited at their characteristic frequencies of motion by a continuous excitation signal. The excited ions in resonant motions generate real or image currents continuously which can be detected and processed to provide a mass spectrum.
Transformation of Rhizobia with Broad-Host-Range Plasmids by Using a Freeze-Thaw Method
Vincze, Eva; Bowra, Steve
2006-01-01
Several species of rhizobia were successfully transformed with broad-host-range plasmids of different replicons by using a modified freeze-thaw method. A generic binary vector (pPZP211) was maintained in Mesorhizobium loti without selection and stably inherited during nodulation. The method could extend the potential of rhizobia as a vehicle for plant transformation.
An improved method for the enzymatic transformation of nucleosides into 5'-monophosphates.
Barai, Vladimir N; Kvach, Sergei V; Zinchenko, Anatoli I; Mikhailopulo, Igor A
2004-12-01
An improved method to transform nucleosides into 5'-monophosphates using nucleoside phosphotransferase from Erwinia herbicola is reported. The method is based on the shift in the equilibrium state of the reaction to the formation of desired product due to its precipitation by Zn2+. Under optimal conditions, the extent of nucleoside transformations into nucleoside-5'-monophosphates were 41-91% (mol). PMID:15672226
Digital Holographic Method for Piezoelectric Transformers Vibration Analysis
Psota, Pavel; Kopecký, V.; Lédl, Vít; Doleček, Roman
Cedex : EDP Sciences, 2013 - (Šulc, M.; Kopecký, V.; Lédl, V.; Melich, R.; Skeren, M.), 00021-00021 ISSN 2100-014X. - (Book Series: EPJ Web of Conferences. 48). [OaM 2012 International Conference on Optics and Measurement. Liberec (CZ), 16.10.2012-18.10.2012] R&D Projects: GA MŠk(CZ) ED2.1.00/03.0079 Institutional support: RVO:61389021 Keywords : Digital holography * vibration analysis * piezoelectric transformers Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering http://www.epj-conferences.org/articles/epjconf/pdf/2013/09/epjconf_OAM2012_00021.pdf
Interdisciplinary Approaches and Methods for Sustainable Transformation and Innovation
Sangkyun Kim
2015-04-01
Full Text Available To increase the likelihood of success and sustainability, organizations must fundamentally reposition themselves and try to change current processes or create new products and services. One of the most effective approaches to find a solution for transformation and innovation is to learn from other domains where a solution for similar problems is already available. This paper briefly introduces the definition of and approaches to convergence of academic disciplines and industries, and overviews several representative convergence cases focusing on gamification for sustainable education, environments, and business managements.
A method of real-time fault diagnosis for power transformers based on vibration analysis
In this paper, a novel probability-based classification model is proposed for real-time fault detection of power transformers. First, the transformer vibration principle is introduced, and two effective feature extraction techniques are presented. Next, the details of the classification model based on support vector machine (SVM) are shown. The model also includes a binary decision tree (BDT) which divides transformers into different classes according to health state. The trained model produces posterior probabilities of membership to each predefined class for a tested vibration sample. During the experiments, the vibrations of transformers under different conditions are acquired, and the corresponding feature vectors are used to train the SVM classifiers. The effectiveness of this model is illustrated experimentally on typical in-service transformers. The consistency between the results of the proposed model and the actual condition of the test transformers indicates that the model can be used as a reliable method for transformer fault detection. (paper)
A method of real-time fault diagnosis for power transformers based on vibration analysis
Hong, Kaixing; Huang, Hai; Zhou, Jianping; Shen, Yimin; Li, Yujie
2015-11-01
In this paper, a novel probability-based classification model is proposed for real-time fault detection of power transformers. First, the transformer vibration principle is introduced, and two effective feature extraction techniques are presented. Next, the details of the classification model based on support vector machine (SVM) are shown. The model also includes a binary decision tree (BDT) which divides transformers into different classes according to health state. The trained model produces posterior probabilities of membership to each predefined class for a tested vibration sample. During the experiments, the vibrations of transformers under different conditions are acquired, and the corresponding feature vectors are used to train the SVM classifiers. The effectiveness of this model is illustrated experimentally on typical in-service transformers. The consistency between the results of the proposed model and the actual condition of the test transformers indicates that the model can be used as a reliable method for transformer fault detection.
Savoye, Philippe
2009-01-01
In recent years, I started covering difference equations and z transform methods in my introductory differential equations course. This allowed my students to extend the "classical" methods for (ordinary differential equation) ODE's to discrete time problems arising in many applications.
Gökdoğan, Ahmet; Merdan, Mehmet; Yildirim, Ahmet
2012-01-01
The goal of this study is presented a reliable algorithm based on the standard differential transformation method (DTM), which is called the multi-stage differential transformation method (MsDTM) for solving Hantavirus infection model. The results obtanied by using MsDTM are compared to those obtained by using the Runge-Kutta method (R-K-method). The proposed technique is a hopeful tool to solving for a long time intervals in this kind of systems.
New Method of R-Wave Detection by Continuous Wavelet Transform
Mourad Talbi, Akram Aouinet, Lotfi Salhi & Adnane Cherif
2011-11-01
Full Text Available In this paper we have employed a new method of R-waves detection in electrocardiogram (ECGsignals. This method is based on the application of the discretised Continuous Wavelet Transform(CWT used for the Bionic Wavelet Transform (BWT. The mother wavelet associated to thistransform is the Morlet wavelet. For evaluating the proposed method, we have compared it toothers methods that are based on Wavelet Transform (WT. In this evaluation, the used ECGsignals are taken from MIT-BIH database. The obtained results show that the proposed methodoutperforms some conventional techniques used in our evaluation.
Fractional modelling for BBM-Burger equation by using new homotopy analysis transform method
Sunil Kumar
2014-10-01
Full Text Available The purpose of this study is to introduce a new analytical method namely, fractional homotopy analysis transform method (FHATM for series solution of the time fractional BBM-Burger equation. The homotopy analysis transform method is an innovative adjustment in Laplace transform algorithm (LTA for nonlinear fractional partial differential equation in fluid dynamics and makes the calculation much simpler. The proposed scheme finds the solutions of nonlinear problems without any discretization, restrictive assumptions and avoids the rounding off errors. The numerical solutions obtained by the proposed method indicate that the approach is easy to implement and computationally very attractive.
A Steganographic Method Based on Integer Wavelet Transform & Genatic Algorithm
Preeti Arora
2014-05-01
Full Text Available The proposed system presents a novel approach of building a secure data hiding technique of steganography using inverse wavelet transform along with Genetic algorithm. The prominent focus of the proposed work is to develop RS-analysis proof design with higest imperceptibility. Optimal Pixal Adjustment process is also adopted to minimize the difference error between the input cover image and the embedded-image and in order to maximize the hiding capacity with low distortions respectively. The analysis is done for mapping function, PSNR, image histogram, and parameter of RS analysis. The simulation results highlights that the proposed security measure basically gives better and optimal results in comparison to prior research work conducted using wavelets and genetic algorithm.
Assessing Strategy of Power Transformers Insulation State Based on Part-division and Entropy Method
LIAO Ruijin; LIU Bin; ZHANG Yiyi; YANG Lijun; ZHENG Hanbo
2013-01-01
Failure mechanisms of power transformers are complex and uncertain; it is difficult to determine index weights of insulation state.Therefore,it is a challenge to acquire an accurate assessment of insulation state of power transformers.In this paper,an assessing strategy for transformer insulation is proposed base on part-division of transformer and a comprehensive weight determination method.An index system of transformer is established on the basis of part-division of transformer.Each index's weight is consisted of two parts,the constant weight and the variable weight,which are determined by improved analytic hierarchy process (AHP) and entropy method respectively.After categorizing insulation state into four levels and standardizing assessing indexes,a Cauchy membership function is forged,and a fuzzy algorithm is employed to simulate the uncertainty of the insulation state.Finally,a confidence criterion is employed to perform part-division based condition assessment of transformer.Case studies reveal that the proposed assessing strategy method is effective,convenient,and practical; with the new strategy,potential failures of transformers can be forecasted and insulation state of transformer parts can also be assessed.Furthermore,the assessing results can be used to guide condition-based maintenance.
Asma Ali Elbeleze; Adem Kılıçman; Bachok M. Taib
2013-01-01
The homotopy perturbation method, Sumudu transform, and He’s polynomials are combined to obtain the solution of fractional Black-Scholes equation. The fractional derivative is considered in Caputo sense. Further, the same equation is solved by homotopy Laplace transform perturbation method. The results obtained by the two methods are in agreement. The approximate analytical solution of Black-Scholes is calculated in the form of a convergence power series with easily computable components. ...
Solutions of the System of Differential Equations by Differential Transform/Finite Difference Method
SÜNGÜ, İnci ÇİLİNGİR; DEMIR, Huseyin
2012-01-01
In this study, Differential Transform/Finite Difference Method is considered as a new solution technique. Discretization of system of first and second order linear and nonlinear differential equations were investigated and approximate solutions were compared with the solutions of Adomian Decomposition Method. The results show that Differential Transform/Finite Difference method is one of the efficient approaches to solve system of differential equations. Consequently, it was shown that the hy...
An effective DOA method via virtual array transformation
无
2001-01-01
A new DOA estimation method is presented for the virtual arraytransformation and the improved spatial smoothing algorithm. The new method not only overcomes the weakness of the ambiguity of DOA estimation of arbitrary array, but also improves the abilities of resolution and de-correlation. It is proven to be effective by theoretical analyses and computer simulations. What is more, the method can improve the estimation and resolution of DOA under the condition of sparse practical array.
Design of piezoelectric transformer for DC/DC converter with stochastic optimization method
Vasic, Dejan; Vido, Lionel
2016-04-01
Piezoelectric transformers were adopted in recent year due to their many inherent advantages such as safety, no EMI problem, low housing profile, and high power density, etc. The characteristics of the piezoelectric transformers are well known when the load impedance is a pure resistor. However, when piezoelectric transformers are used in AC/DC or DC/DC converters, there are non-linear electronic circuits connected before and after the transformer. Consequently, the output load is variable and due to the output capacitance of the transformer the optimal working point change. This paper starts from modeling a piezoelectric transformer connected to a full wave rectifier in order to discuss the design constraints and configuration of the transformer. The optimization method adopted here use the MOPSO algorithm (Multiple Objective Particle Swarm Optimization). We start with the formulation of the objective function and constraints; then the results give different sizes of the transformer and the characteristics. In other word, this method is looking for a best size of the transformer for optimal efficiency condition that is suitable for variable load. Furthermore, the size and the efficiency are found to be a trade-off. This paper proposes the completed design procedure to find the minimum size of PT in need. The completed design procedure is discussed by a given specification. The PT derived from the proposed design procedure can guarantee both good efficiency and enough range for load variation.
Transforming student's discourse as a method of teaching science inquiry
Livingston, David
2005-07-01
A qualitative case study on the instructional practice of one secondary science teacher addresses the persistent reluctance of many science teachers to integrate the cultural resources and social practices of professional science communities into the science content they teach. The literature has shown that teachers' hesitation to implement a social and locally situated learning strategy curtails students' ability to draw upon the language of science necessary to co-construct and shape authentic science inquiry and in particular appropriate argument schemes. The study hypothesized that a teacher's dialogic facilitation of a particular social context and instructional practices enhances a students' ability to express verbally the claims and warrants that rise from evidence taken from their inquiries of natural phenomena. The study also tracks students' use of the Key Words and Ideas of this science curriculum for the purpose of assessing the degree of students' assimilation of these terms into their speech and written expressions of inquiry. The theoretical framework is Vygotskian (1978) and the analysis of the qualitative data is founded on Toulmin (1958), Walton (1996), Jimenez-Alexandre et al. (2000) and Shavelson (1996). The dialogic structure of this teacher's facilitation of student's science knowledge is shown to utilize students' presumptive statements to hone their construction of inductive or deductive arguments. This instructional practice may represent teacher-student activity within the zone of proximal development and supports Vygotsky's notion that a knowledgeable other is instrumental in transforming student's spontaneous talk into scientific speech. The tracking of the curriculum's Key Words and Ideas into students' speech and writing indicated that this teachers' ability to facilitate students' presumptuous reasoning into logic statements did not necessarily guarantee that they could post strong written expressions of this verbal know-how in
Method of integral transforms for calculating few-body reactions
Efros, V. D.; Leidemann, W.; Orlandini, G.
1998-01-01
A non-conventional approach to calculating reactions in quantum mechanics is presented. Reaction observables are obtained with bound state calculation techniques. The accuracy of the method to calculate few-nucleon response functions is discussed.
Peles, S.; Warnecke, G.
2000-07-01
Companies ask more and more how to develop their products in a recycling oriented way, in order to increase their marketability and competitiveness as well as to gain economic benefits. So far, to answer this question, companies are not sufficiently supported by suitable methods. The Institute for Manufacturing Engineering and Production Management (FBK) at the University of Kaiserslautern has developed in collaboration with an industrial partner a new method for company-specific, systematic evaluation and transformation of recycling demands throughout the product development process. In the presented paper this method will be described in detail. Selected examples and experiences of the practical evaluation on capital goods illustrate the method steps and their implementation within a company. (orig.) [German] Immer mehr Unternehmen stellen sich die Frage, wie sie ihre Produkte recyclinggerecht entwickeln koennen, um deren Marktfaehigkeit bzw. Konkurrenzfaehigkeit zu steigern und um wirtschaftliche Vorteile zu erzielen. Die heutige Unternehmenspraxis wird diesbezueglich noch nicht ausreichend durch entsprechende Methoden unterstuetzt. Der Lehrstuhl fuer Fertigungstechnik und Betriebsorganisation der Universitaet Kaiserslautern hat gemeinsam mit einem Industriepartner eine Methodik zur unternehmensspezifischen, systematischen Ermittlung und Transformation von Recyclinganforderungen in der Produktentwicklung erarbeitet. Im vorliegenden Beitrag wird diese Methodik naeher beschrieben. Ausgewaehlte Beispiele und Erkenntnisse der praktischen Umsetzung an technischen Investitionsguetern veranschaulichen die Vorgehensweise innerhalb der Methodik und deren Implementierung im Unternehmen. (orig.)
Phase difference estimation method based on data extension and Hilbert transform
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)
Multimodal Medical Image Fusion Methods Based on Improved Discrete Wavelet Transform
XU Lei; TIAN Shu-chang; CUI Can; MENG Qing-le; YANG Rui; JIANG Hong-bing; WANG Feng
2016-01-01
Objective This paper proposed a novel algorithm of discrete wavelet transform (DWT) which is used for multimodal medical image fusion.Methods The source medical images are initially transformed by DWT followed by fusing low and high frequency sub-images. Then, the “coefficient absolute value” that can provide clear and detail parts is adapted to fuse high-frequency coefifcients, where as the “region energy ratio” which can efifciently preserve most information of source images is employed to fuse low-frequency coefifcients. Finally, the fused image is reconstructed by inverse wavelet transform.Results Visually and quantitatively experimental results indicate that the proposed fusion method is superior to traditional wavelet transform and the existing fusion methods.Conclusion The proposed method is a feasible approach for multimodal medical image fusion which can obtain more efifcient and accurate fusions results even in the noise environment.
Improved method of generating bit reversed numbers for calculating fast fourier transform
Suresh, T.
Fast Fourier Transform (FFT) is an important tool required for signal processing in defence applications. This paper reports an improved method for generating bit reversed numbers needed in calculating FFT using radix-2. The refined algorithm takes...
Described are methods to measure the polychlorinated biphenyl (PCB) emissions from the stacks of municipal waste, industrial waste, and sewage sludge incinerators and from capacitor and transformer filling plants. The PCB emissions from the incineration plants are collected by im...
Abdalla Ahmed Abdel-Ghaly; Hanan Mohamed Aly; Elham Abdel-Malik Abde-Rahman
2016-01-01
This paper suggests the use of the conditional probability integral transformation (CPIT) method as a goodness of fit (GOF) technique in the field of accelerated life testing (ALT), specifically for validating the underlying distributional assumption in accelerated failure time (AFT) model. The method is based on transforming the data into independent and identically distributed (i.i.d) Uniform (0, 1) random variables and then applying the modified Watson statistic to test the uniformity of t...
Advantages of Analytical Transformations in Monte Carlo Methods for Radiation Transport
Monte Carlo methods for radiation transport typically attempt to solve an integral by directly sampling analog or weighted particles, which are treated as physical entities. Improvements to the methods involve better sampling, probability games or physical intuition about the problem. We show that significant improvements can be achieved by recasting the equations with an analytical transform to solve for new, non-physical entities or fields. This paper looks at one such transform, the difference formulation for thermal photon transport, showing a significant advantage for Monte Carlo solution of the equations for time dependent transport. Other related areas are discussed that may also realize significant benefits from similar analytical transformations
Energy Based Correlation Method for Location of Partial Discharge in Transformer Winding
JEYABALAN, V.
2009-02-01
Full Text Available Partial discharge (PD is the major source of insulation failure in power transformer. When transformers are subjected to electrical stress during operation, PD can occur. PD identification is an important diagnostic tool for the reliable operation of transformers. The PD signal detection and location is one of the main challenges for system utilities and equipment manufacturers. In this paper energy based correlation method is proposed for locating the source of PD for different pulse durations. Simulation and experiment are performed on lumped physical layer winding to prove the feasibility of the method and also verified with distributed model of 22kV prototype interleaved winding.
Petr Orsag
2008-01-01
Full Text Available In this paper a new method of identification of both the magnetization characteristic and the instantaneous parameters G(t and K(t of a single-phase transformer under a sinusoidal supply voltage is proposed. The instantaneous conductance G(t and inverse inductance K(t of the transformer cross section are determined by the scalar product of time functions. The magnetization characteristic is derived by means of the inverse inductance K(t. The method is practically applied to an isolating transformer.
Rapid DNA transformation in Salmonella Typhimurium by the hydrogel exposure method.
Elabed, Hamouda; Hamza, Rim; Bakhrouf, Amina; Gaddour, Kamel
2016-07-01
Even with advances in molecular cloning and DNA transformation, new or alternative methods that permit DNA penetration in Salmonella enterica subspecies enterica serovar Typhimurium are required in order to use this pathogen in biotechnological or medical applications. In this work, an adapted protocol of bacterial transformation with plasmid DNA based on the "Yoshida effect" was applied and optimized on Salmonella enterica serovar Typhimurium LT2 reference strain. The plasmid transference based on the use of sepiolite as acicular materials to promote cell piercing via friction forces produced by spreading on the surface of a hydrogel. The transforming mixture containing sepiolite nanofibers, bacterial cells to be transformed and plasmid DNA were plated directly on selective medium containing 2% agar. In order to improve the procedure, three variables were tested and the transformation of Salmonella cells was accomplished using plasmids pUC19 and pBR322. Using the optimized protocol on Salmonella LT2 strain, the efficiency was about 10(5) transformed cells per 10(9) subjected to transformation with 0.2μg plasmid DNA. In summary, the procedure is fast, offers opportune efficiency and promises to become one of the widely used transformation methods in laboratories. PMID:27154729
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.
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
Methods for transforming and expression screening of filamentous fungal cells with a DNA library
Teter, Sarah; Lamsa, Michael; Cherry, Joel; Ward, Connie
2015-06-02
The present invention relates to methods for expression screening of filamentous fungal transformants, comprising: (a) isolating single colony transformants of a DNA library introduced into E. coli; (b) preparing DNA from each of the single colony E. coli transformants; (c) introducing a sample of each of the DNA preparations of step (b) into separate suspensions of protoplasts of a filamentous fungus to obtain transformants thereof, wherein each transformant contains one or more copies of an individual polynucleotide from the DNA library; (d) growing the individual filamentous fungal transformants of step (c) on selective growth medium, thereby permitting growth of the filamentous fungal transformants, while suppressing growth of untransformed filamentous fungi; and (e) measuring activity or a property of each polypeptide encoded by the individual polynucleotides. The present invention also relates to isolated polynucleotides encoding polypeptides of interest obtained by such methods, to nucleic acid constructs, expression vectors, and recombinant host cells comprising the isolated polynucleotides, and to methods of producing the polypeptides encoded by the isolated polynucleotides.
M. Rasoulpoor; M. Banejad; A.R. Ahmadyfard
2013-01-01
This paper presents a new approach for power transformer differential protection. The Wavelet Transform is applied to discriminate between inrush currents and internal fault currents in power transformers. Discrete wavelet transform decomposes the current signal into sub-bands that give more information about the properties of the signals in different frequency bands. Also, this transform is used to investigate the energy distribution of the signal on the different time and frequency scales. ...
Research of an Improved Wavelet Threshold Denoising Method for Transformer Partial Discharge Signal
Fucheng You
2013-02-01
Full Text Available In order to overcome the discontinuance of the hard thresholding function and the defect of seriously slashing singularity in the soft thresholding function, improve the denoising effect and detect the transformer partial discharge signal more accurately, in this paper an improved wavelet threshold denoising method is put forward through analyzing the interference noise of transformer partial discharge signals and studying various wavelet threshold denoising method, especially the wavelet threshold denoising method that overcomes the shortcomings of the hard and soft threshold. Simulation results show that the denoising effect of this method has been greatly improved than the traditional hard and soft threshold method. This method can be widely used in practical transformer partial discharge signal denoising.
A Single Monitor Method for Voltage Sag Source Location using Hilbert Huang Transform
Wong Ling Ai
2013-01-01
Full Text Available This study introduces a method for voltage sag source location based on Hilbert Huang transformed monitored current signal. Unlike the traditional method, the proposed method first transforms the recorded current during the sag event to obtain frequency-time plot (Hilbert spectra and IMF plot before the location of voltage sag source is determined. Then based on the change in frequency and IMF the relative location of voltage sag source is obtained. The effectiveness of the proposed method has been verified through simulation on 20 bus system and by comparing with an existing S-Transform based method. The results show that the presented method can determine the location of voltage sag source correctly.
Xu, Kedong; Huang, Xiaohui; Wu, Manman; Wang, Yan; Chang, Yunxia; Liu, Kun; Zhang, Ju; Zhang, Yi; Zhang, Fuli; Yi, Liming; Li, Tingting; Wang, Ruiyue; Tan, Guangxuan; Li, Chengwei
2014-01-01
Transient transformation is simpler, more efficient and economical in analyzing protein subcellular localization than stable transformation. Fluorescent fusion proteins were often used in transient transformation to follow the in vivo behavior of proteins. Onion epidermis, which has large, living and transparent cells in a monolayer, is suitable to visualize fluorescent fusion proteins. The often used transient transformation methods included particle bombardment, protoplast transfection and ...
Naoto Yoshida
2007-01-01
Full Text Available Escherichia coli as a plasmid recipient cell was dispersed in a chrysotile colloidal solution, containing chrysotile adsorbed to plasmid DNA (chrysotile-plasmid cell mixture. Following this, the chrysotile-plasmid cell mixture was dropped onto the surface of an elastic body, such as agarose, and treated physically by sliding a polystyrene streak bar over the elastic body to create friction. Plasmid DNA was easily incorporated into E. coli, and antibiotic resistance was conferred by transformation. The transformation efficiency of E. coli cultured in solid medium was greater than that of E. coli cultured in broth. To obtain greater transformation efficiency, we attempted to determine optimal transformation conditions. The following conditions resulted in the greatest transformation efficiency: the recipient cell concentration within the chrysotileplasmid cell mixture had an optical density greater than or equal to 2 at 550 nm, the vertical reaction force applied to the streak bar was greater than or equal to 40 g, and the rotation speed of the elastic body was greater than or equal to 34 rpm. Under these conditions, we observed a transformation efficiency of 107 per μg plasmid DNA. The advantage of achieving bacterial transformation using the elastic body exposure method is that competent cell preparation of the recipient cell is not required. In addition to E. coli, other Gram negative bacteria are able to acquire plasmid DNA using the elastic body exposure method.
Multistep epsilon-algorithm, Shanks' transformation, and Lotka-Volterra system by Hirota's method
Brezinski, Claude; Hu, Xing-Biao; Redivo-Zaglia, Michela; Sun, Jian-Qing
2010-01-01
In this paper, we give a multistep extension of the epsilon-algorithm of Wynn, and we show that it implements a multistep extension of the Shanks' sequence transformation which is defined by ratios of determinants. Reciprocally, the quantities defined in this transformation can be recursively computed by the multistep epsilon-algorithm. The multistep epsilon-algorithm and the multistep Shanks' transformation are related to an extended discrete Lotka-Volterra system. These results are obtained by using the Hirota's bilinear method, a procedure quite useful in the solution of nonlinear partial differential and difference equations.
A novel approach for solving fractional Fisher equation using differential transform method
MIRZAZADEH M
2016-05-01
In the present paper, an analytic solution of nonlinear fractional Fisher equation is deduced with the help of the powerful differential transform method (DTM). To illustrate the method, two examples have been prepared. The method for this equation has led to an exact solution. The reliability, simplicity and cost-effectiveness of the method are confirmed by applying this method on different forms of functional equations.
Schenk, A.; Germond, A. [Ecole Polytechnique Federale de Lausanne, Lausanne (Switzerland); Boss, P.; Lorin, P. [ABB Secheron SA, Geneve (Switzerland)
2000-07-01
The article describes a new method for the continuous surveillance of power transformers based on the application of artificial intelligence (AI) techniques. An experimental pilot project on a specially equipped, strategically important power transformer is described. Traditional surveillance methods and the use of mathematical models for the prediction of faults are described. The article describes the monitoring equipment used in the pilot project and the AI principles such as self-organising maps that are applied. The results obtained from the pilot project and methods for their graphical representation are discussed.
Calculation of corrections to shell-model by local-scale transformation method
A methodological investigation of the general local-scale transformation method (LSTM) in the case of an axial deformation are performed. Numerical results for the LSTM transformation function are analyzed and compared with the results of the spherically symmetric case. Results of particular calculations for the 4He, 16O and 40Ca nuclei obtained by an iterative procedure are given. 7 figs., 1 tabs., 7 refs
Method Support of Large-Scale Transformation in the Insurance Sector: Exploring Foundations
Labusch, Nils; Winter, Robert, ed.imp.lib
2012-01-01
Many enterprises need to handle programs that impose fundamental changes to the organization as well as the supporting IT systems. While general guidance for such transformations in form of methods, reference models, principles, etc. is available, the specific context of the insurance sector is often not considered. We conducted an interview series with informants from major European insurance companies to explore the specifics of enterprise transformation in the insurance sector. The results...
Research of an Improved Wavelet Threshold Denoising Method for Transformer Partial Discharge Signal
Fucheng You; Ying Zhang
2013-01-01
In order to overcome the discontinuance of the hard thresholding function and the defect of seriously slashing singularity in the soft thresholding function, improve the denoising effect and detect the transformer partial discharge signal more accurately, in this paper an improved wavelet threshold denoising method is put forward through analyzing the interference noise of transformer partial discharge signals and studying various wavelet threshold denoising meth...
Practical challenges for methods transforming i* goal models into business process models.
Decreus, Ken; Snoeck, Monique; Poels, Geert
2009-01-01
The field of requirements engineering for business processes has grown during the last several years. As business processes are assumed to fulfil organizational goals, goal models could be transformed into business process models that specify how business processes fulfil the organizational goals. Although both the fields of Goal-Oriented RE (GORE) and Business Process Management (BPM) received a lot of attention from researchers, the methods to transform goal models into business process mod...
Mark, A. F.; Moat, R.; Forsey, A.; Abdolvand, H; Withers, P.J.
2014-01-01
Martensitic phase transformations during welding can play a major role in determining the final residual stresses and they can be anisotropic if the transformation occurs under stress. Traditionally, the Satoh test has been used to quantify the response, but it suffers from the fact that the temperature is not uniform along the specimen length, making it difficult to interpret the data. This shortcoming is overcome in our new experimental method using digital image correlation (DIC) to quanti...
Ülker Bekir
2006-10-01
Full Text Available Abstract Background The Agrobacterium vacuum (Bechtold et al 1993 and floral-dip (Clough and Bent 1998 are very efficient methods for generating transgenic Arabidopsis plants. These methods allow plant transformation without the need for tissue culture. Large volumes of bacterial cultures grown in liquid media are necessary for both of these transformation methods. This limits the number of transformations that can be done at a given time due to the need for expensive large shakers and limited space on them. Additionally, the bacterial colonies derived from solid media necessary for starting these liquid cultures often fail to grow in such large volumes. Therefore the optimum stage of plant material for transformation is often missed and new plant material needs to be grown. Results To avoid problems associated with large bacterial liquid cultures, we investigated whether bacteria grown on plates are also suitable for plant transformation. We demonstrate here that bacteria grown on plates can be used with similar efficiency for transforming plants even after one week of storage at 4°C. This makes it much easier to synchronize Agrobacterium and plants for transformation. DNA gel blot analysis was carried out on the T1 plants surviving the herbicide selection and demonstrated that the surviving plants are indeed transgenic. Conclusion The simplified method works as efficiently as the previously reported protocols and significantly reduces the workload, cost and time. Additionally, the protocol reduces the risk of large scale contaminations involving GMOs. Most importantly, many more independent transformations per day can be performed using this modified protocol.
Sora Kim
Full Text Available Genetic engineering in microalgae is gaining attraction but nuclear transformation methods available so far are either inefficient or require special equipment. In this study, we employ positively charged nanoparticles, 3-aminopropyl-functionalized magnesium phyllosilicate (aminoclay, approximate unit cell composition of [H2N(CH23]8Si8Mg6O12(OH4, for nuclear transformation into eukaryotic microalgae. TEM and EDX analysis of the process of transformation reveals that aminoclay coats negatively-charged DNA biomolecules and forms a self-assembled hybrid nanostructure. Subsequently, when this nanostructure is mixed with microalgal cells and plated onto selective agar plates with high friction force, cell wall is disrupted facilitating delivery of plasmid DNA into the cell and ultimately to the nucleus. This method is not only simple, inexpensive, and non-toxic to cells but also provides efficient transformation (5.03×10(2 transformants/µg DNA, second only to electroporation which needs advanced instrumentation. We present optimized parameters for efficient transformation including pre-treatment, friction force, concentration of foreign DNA/aminoclay, and plasticity of agar plates. It is also confirmed the successful integration and stable expression of foreign gene in Chlamydomonas reinhardtii through molecular methods.
Multi-level denoising and enhancement method based on wavelet transform for mine monitoring
Yanqin Zhao
2013-01-01
Based on low illumination and a large number of mixed noises contained in coal mine,denoising with one method usually cannot achieve good results,So a multi-level image denoising method based on wavelet correlation relevant inter-scale is presented.Firstly,we used directional median filter to effectively reduce impulse noise in the spatial domain,which is the main cause of noise in mine.Secondly,we used a Wiener filtration method to mainly reduce the Gaussian noise,and then finally used a multi-wavelet transform to minimize the remaining noise of low-light images in the transform domain.This multi-level image noise reduction method combines spatial and transform domain denoising to enhance benefits,and effectively reduce impulse noise and Gaussian noise in a coal mine,while retaining good detailed image characteristics of the underground for improving quality of images with mixing noise and effective low-light environment.
Efficient method for localized functions using domain transformation and Fourier sine series
Jovanovic, Raka; Alharbi, Fahhad H
2014-01-01
An efficient approach to handle localized states by using spectral methods (SM) in one and three dimensions is presented. The method consists of transformation of the infinite domain to the bounded domain in $(0, \\pi)$ and using the Fourier sine series as a set of basis functions for the SM. It is shown that with an appropriate choice of transformation functions, this method manages to preserve the good properties of original SMs; more precisely, superb computational efficiency when high level of accuracy is necessary. This is made possible by analytically exploiting the properties of the transformation function and the Fourier sine series. An especially important property of this approach is the possibility of calculating the Hartree energy very efficiently. This is done by exploiting the positive properties of the sine series as a basis set and conducting an extinctive part of the calculations analytically. We illustrate the efficiency of this method and implement it to solve the Poisson's and Helmholtz equ...
MATHEMATICAL PROBLEMS IN THE INTEGRAL-TRANSFORMATION METHOD OF DYNAMIC CRACK
边文凤; 王彪; 贾宝贤
2004-01-01
In the investigation on fracture mechanics,the potential function was introduced, and the moving differential equation was constructed. By making Laplace and Fourier transformation as well as sine and cosine transformation to moving differential equations and various responses, the dual equation which is constructed from boundary conditions lastly was solved. This method of investigating dynamic crack has become a more systematic one that is used widely. Some problems are encountered when the dynamic crack is studied. After the large investigation on the problems, it is discovered that during the process of mathematic derivation, the method is short of precision, and the derived results in this method are accidental and have no credibility.A model for example is taken to explain the problems existing in initial deriving process of the integral-transformation method of dynamic crack.
Abdalla Ahmed Abdel-Ghaly
2016-06-01
Full Text Available This paper suggests the use of the conditional probability integral transformation (CPIT method as a goodness of fit (GOF technique in the field of accelerated life testing (ALT, specifically for validating the underlying distributional assumption in accelerated failure time (AFT model. The method is based on transforming the data into independent and identically distributed (i.i.d Uniform (0, 1 random variables and then applying the modified Watson statistic to test the uniformity of the transformed random variables. This technique is used to validate each of the exponential, Weibull and lognormal distributions' assumptions in AFT model under constant stress and complete sampling. The performance of the CPIT method is investigated via a simulation study. It is concluded that this method performs well in case of exponential and lognormal distributions. Finally, a real life example is provided to illustrate the application of the proposed procedure.
H. M. Abdelhafez
2016-03-01
Full Text Available The modified differential transform method (MDTM, Laplace transform and Padé approximants are used to investigate a semi-analytic form of solutions of nonlinear oscillators in a large time domain. Forced Duffing and forced van der Pol oscillators under damping effect are studied to investigate semi-analytic forms of solutions. Moreover, solutions of the suggested nonlinear oscillators are obtained using the fourth-order Runge-Kutta numerical solution method. A comparison of the result by the numerical Runge-Kutta fourth-order accuracy method is compared with the result by the MDTM and plotted in a long time domain.
Gou Fu-Yan; Liu Cai; Liu Yang; Feng Xuan; Cui Fang-Zi
2014-01-01
In seismic prospecting,fi eld conditions and other factors hamper the recording of the complete seismic wavefi eld; thus, data interpolation is critical in seismic data processing. Especially, in complex conditions, prestack missing data affect the subsequent high-precision data processing workfl ow. Compressive sensing is an effective strategy for seismic data interpolation by optimally representing the complex seismic wavefi eld and using fast and accurate iterative algorithms. The seislet transform is a sparse multiscale transform well suited for representing the seismic wavefield, as it can effectively compress seismic events. Furthermore, the Bregman iterative algorithm is an efficient algorithm for sparse representation in compressive sensing. Seismic data interpolation methods can be developed by combining seismic dynamic prediction, image transform, and compressive sensing. In this study, we link seismic data interpolation and constrained optimization. We selected the OC-seislet sparse transform to represent complex wavefields and used the Bregman iteration method to solve the hybrid norm inverse problem under the compressed sensing framework. In addition, we used an H-curve method to choose the threshold parameter in the Bregman iteration method. Thus, we achieved fast and accurate reconstruction of the seismic wavefi eld. Model andfi eld data tests demonstrate that the Bregman iteration method based on the H-curve norm in the sparse transform domain can effectively reconstruct missing complex wavefi eld data.
Eijnden-van Raaij, A.J.M. van den; Koornneef, I.; Zoelen, E.J.J. van
1988-01-01
A new method was developed for the purification of type beta transforming growth factor from human platelets. This method is a three-step procedure including gel filtration, weak cation exchange HPLC and reverse phase HPLC. All steps are carried out at low pH using exclusively volatile acidic buffer
A new chemometric method based on absorbance ratios from Fourier transform infrared spectra was devised to analyze multicomponent biodegradable plastics. The method uses the BeerLambert law to directly compute individual component concentrations and weight losses before and after biodegradation of c...
Chen, Xi; Stone, Michelle; Schlagnhaufer, Carl; Romaine, C. Peter
2000-01-01
We describe a modified Agrobacterium-mediated method for the efficient transformation of Agaricus bisporus. Salient features of this procedure include cocultivation of Agrobacterium and fruiting body gill tissue and use of a vector with a homologous promoter. This method offers new prospects for the genetic manipulation of this commercially important mushroom species.
Evaluation of the neutron flux-depression factor via the integral transform method
The integral transform method is used to solve a two-region problem relevant to the evaluation of a neutron flux-depression factor. For the latter, numerical results are reported for different values of the physical parameters involved and compared with those obtained through other methods
The Telegraph Equation and Its Solution by Reduced Differential Transform Method
Vineet K. Srivastava; Mukesh K. Awasthi; R. K. Chaurasia; M. Tamsir
2013-01-01
One-dimensional second-order hyperbolic telegraph equation was formulated using Ohm’s law and solved by a recent and reliable semianalytic method, namely, the reduced differential transform method (RDTM). Using this method, it is possible to find the exact solution or a closed approximate solution of a differential equation. Three numerical examples have been carried out in order to check the effectiveness, the accuracy, and convergence of the method. The RDTM is a powerful mathematical techn...
TDA method application to austenite transformation in nodular cast iron with carbides assessment
G. Gumienny
2011-07-01
Full Text Available In this paper the possibility of TDA method using to austenite transformation in nodular cast iron with carbides assessment is presented. Studies were conducted on cast iron with about 2% molybdenum and 0,70% to 4,50% nickel. On diagrams, where TDA curves are pre- sented, on time axis a logarithmic scale was applied. It has not been used up to now. It was found, that during cooling and crystallization of cast iron in TDA probe, on the derivative curve there is a slight thermal effect from austenite to upper bainite or martensite transformation. Depending on nickel concentration austeniteupper bainite transformation start temperature changed (Bus, while MS temperature was independent of it. An influence of nickel on eutectic transformation temperature in nodular cast iron with carbides was determined too.
We develop a 'Local' Exponential Transform method which distributes the particles nearly uniformly across the system in Monte Carlo transport calculations. An exponential approximation to the continuous transport equation is used in each mesh cell to formulate biasing parameters. The biasing parameters, which resemble those of the conventional exponential transform, tend to produce a uniform sampling of the problem geometry when applied to a forward Monte Carlo calculation, and thus they help to minimize the maximum variance of the flux. Unlike the conventional exponential transform, the biasing parameters are spatially dependent, and are automatically determined from a forward diffusion calculation. We develop two versions of the forward Local Exponential Transform method, one with spatial biasing only, and one with spatial and angular biasing. The method is compared to conventional geometry splitting/Russian roulette for several sample one-group problems in X-Y geometry. The forward Local Exponential Transform method with angular biasing is found to produce better results than geometry splitting/Russian roulette in terms of minimizing the maximum variance of the flux. (orig.)
2D Satellite Image Registration Using Transform Based and Correlation Based Methods
Dr. H.B. Kekre, Dr. Tanuja K. Sarode, Ms. Ruhina B. Karani
2012-05-01
Full Text Available Image registration is the process of geometrically aligning one image to another image of the same scene taken from different viewpoints or by different sensors. It is a fundamental image processing technique and is very useful in integrating information from different sensors, finding changes in images taken at different times and inferring three-dimensional information from stereo images. Image registration can be done by using two matching method: transform based methods and correlation based methods. When image registration is done using correlation based methods like normalized cross correlation, the results are slow. They are also computationally complex and sensitive to the image intensity changes which are caused by noise and varying illumination. In this paper, an unusual form of image registration is proposed which focuses upon using various transforms for fast and accurate image registration. The data set can be a set of photographs, data from various sensors, from different times, or from different viewpoints. The applications of image registration are in the field of computer vision, medical imaging, military automatic target recognition, and in analyzing images and data from satellites. The proposed technique works on satellite images. It tries to find out area of interest by comparing the unregistered image with source image and finding the part that has highest similarity matching. The paper mainly works on the concept of seeking water or land in the stored image. The proposed technique uses different transforms like Discrete Cosine Transform, Discrete Wavelet Transform, HAAR Transform and Walsh transform to achieve accurate image registration. The paper also focuses upon using normalized cross correlation as an area based technique of image registration for the purpose of comparison. The root mean square error is used as similarity measure. Experimental results show that the proposed algorithm can successfully register the
Ntsama, Eloundou Pascal; Colince, Welba; Ele, Pierre
2016-01-01
In this article, we make a comparative study for a new approach compression between discrete cosine transform (DCT) and discrete wavelet transform (DWT). We seek the transform proper to vector quantization to compress the EMG signals. To do this, we initially associated vector quantization and DCT, then vector quantization and DWT. The coding phase is made by the SPIHT coding (set partitioning in hierarchical trees coding) associated with the arithmetic coding. The method is demonstrated and evaluated on actual EMG data. Objective performance evaluations metrics are presented: compression factor, percentage root mean square difference and signal to noise ratio. The results show that method based on the DWT is more efficient than the method based on the DCT. PMID:27104132
A method based on IHS cylindrical transform model for quality assessment of image fusion
Zhu, Xiaokun; Jia, Yonghong
2005-10-01
Image fusion technique has been widely applied to remote sensing image analysis and processing, and methods for quality assessment of image fusion in remote sensing have also become the research issues at home and abroad. Traditional assessment methods combine calculation of quantitative indexes and visual interpretation to compare fused images quantificationally and qualitatively. However, in the existing assessment methods, there are two defects: on one hand, most imdexes lack the theoretic support to compare different fusion methods. On the hand, there is not a uniform preference for most of the quantitative assessment indexes when they are applied to estimate the fusion effects. That is, the spatial resolution and spectral feature could not be analyzed synchronously by these indexes and there is not a general method to unify the spatial and spectral feature assessment. So in this paper, on the basis of the approximate general model of four traditional fusion methods, including Intensity Hue Saturation(IHS) triangle transform fusion, High Pass Filter(HPF) fusion, Principal Component Analysis(PCA) fusion, Wavelet Transform(WT) fusion, a correlation coefficient assessment method based on IHS cylindrical transform is proposed. By experiments, this method can not only get the evaluation results of spatial and spectral features on the basis of uniform preference, but also can acquire the comparison between fusion image sources and fused images, and acquire differences among fusion methods. Compared with the traditional assessment methods, the new methods is more intuitionistic, and in accord with subjective estimation.
Armanini, D.; Bosotti, O.; Centemeri, A.; Ghirelli, L.; Romani, C.; Vallini, F. (ENEL, Cologno Monzese (Italy). Centro di Ricerca Elettrica CESI, Milan (Italy))
1989-05-01
A short introduction on the problems met by HV current-transformers with paper-oil insulation when subjected to steep-front transients caused by disconnector operations, is followed by a description of test methods that enable these service stresses to be simulated in the laboratory. The results of experimental research carried out on various types of current transformers have shown the effectiveness of the methods proposed, and have given useful indications of requirements on the subject that might be introducted into existing CT standards.
Petr Orsag; Jaromir Kijonka
2008-01-01
In this paper a new method of identification of both the magnetization characteristic and the instantaneous parameters G(t) and K(t) of a single-phase transformer under a sinusoidal supply voltage is proposed. The instantaneous conductance G(t) and inverse inductance K(t) of the transformer cross section are determined by the scalar product of time functions. The magnetization characteristic is derived by means of the inverse inductance K(t). The method is practically applied to an isolating ...
Lifeng Wang
2015-01-01
Full Text Available The method based on the continuous wavelet transformation to detect and characterize two-dimensional vortex is analyzed for a synthetic flow and applied to vortex detection of propeller wake. The characteristics of a vortex, such as center location, core radius, and circulation, are extracted based on the Lamb-Oseen and Rankine vortex models, the latter of which is a novel attempt. The effects of various factors such as the difference scheme, the grid and scale discretization, transform variable, and vortex model on vortex detection have been investigated thoroughly. The method is further applied to identify the tip vortex in a propeller wake.
Research of on-line monitoring method for insulation condition of power transformer bushing
Xia, Jiuyun; Qian, Zheng; Yu, Hao; Yao, Junda
2016-01-01
The power transformer is the key equipment of the power system; its insulation condition will directly influence the security and reliability of the power system. Thus, the on-line monitoring of power transformer is urgently required in order to guarantee the normal operation of the power system. Moreover, the dielectric loss factor is a significant parameter reflecting the condition of transformer bushing, so the on-line measurement of dielectric loss factor is really important. In this paper, the phase-to-phase comparison method is selected as the on-line monitoring method based on the overall analysis and discussion of the existing on-line monitoring methods. At first, the harmonic analysis method is utilized to calculate the dielectric loss of each phase of the three-phase transformer bushing, and then the differences of dielectric loss between every two phases are calculated and analyzed. So the insulation condition of each bushing could be achieved based on the careful analysis of different phase-to-phase dielectric loss. The simulation results of phase-to-phase comparison method are carried out in this paper, and the validity is verified. At last, this method is utilized in an actual equipment of on-line monitoring.
Setaria viridis floral-dip: A simple and rapid Agrobacterium-mediated transformation method
Polyana Kelly Martins
2015-06-01
Full Text Available Setaria viridis was recently described as a new monocotyledonous model species for C4 photosynthesis research and genetic transformation. It has biological attributes (rapid life cycle, small genome, diploid, short stature and simple growth requirements that make it suitable for use as a model plant. We report an alternative method of S. viridis transformation using floral dip to circumvent the necessity of tissue culture phase for transgenic plant regeneration. S. viridis spikes at boot stage were selected to be immersed in Agrobacterium suspension. T1 seeds could be identified in 1.5–2 months after floral dipping. We demonstrated through molecular analysis and RFP expression that seeds and resulting plants from dipped inflorescences were transformed. Our results suggest the feasibility of S. viridis floral dip transformation as a time-saving and cost-effective compared with traditional methods. To our knowledge, this is the first report using floral dip in S. viridis as an Agrobacterium-mediated transformation method.
Song, Jinzhong; Yan, Hong; Li, Yanjun; Mu, Kaiyu
2010-09-01
Baseline wandering in electrocardiogram (ECG) is one of the biggest interferences in visualization and computerized detection of waveforms (especially ST-segment) based on threshold decision. A new method based on wavelet transform, QRS barycenter fitting and regional method was proposed in this paper. Firstly, wavelet transform as a coarse correction was used to remove the baseline wandering, whose frequency bands were non-overlapping with that of ST-segment. Secondly, QRS barycenter fitting was applied as a detailed correction. The third, the regional method was used to transfer baseline to zero. Finally, the method in this paper was proved to perform better than filtering and function fitting methods in baseline wandering correction after the long-term ST database (LTST) verification. In addition, the proposed method is simple and easy to carry out, and in current use. PMID:20882381
M. Rasoulpoor
2011-12-01
Full Text Available 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 inrush and internal fault current signals of power transformer. The correlation factor which is a statistical parameter is used here to express the pattern of the energy distribution for different current signals. The proposed algorithm is based on the correlation factors to distinguish between internal fault and inrush currents in the transformer differentialprotection. The proposed algorithm is tested and simulated for several cases by simulating inrush and internal fault currents. The simulation of inrush and internal fault currents are performed using electromagnetic transient program PSCAD/EMTDC software. Simulation results show that the proposed scheme accurately identifies inrush and fault currents at the distance of the power transformer protection in a time period less than quarter of power frequency cycle. In addition the proposed method has high sensitivity and reliability. The method has low computation work and not requires determining the threshold for each new power system.
WAVELET TRANSFORM METHOD FOR DERIVING ATMOSPHERIC BOUNDARY LAYER HEIGHT FROM LIDAR SIGNALS
RAJITHA PALETI
2013-04-01
Full Text Available Wavelet method of determining the atmospheric boundary layer (ABL height from lidar signals is presented in this paper. The wavelet covariance transform (WCT method employed determines the significant gradient in the measured lidar signals. Using this method, the accuracy of ABL height detection enhances with increased dilation length. The developed wavelet algorithm is coded in MATLAB software and has a provision to alter the dilation length in real-time for a given translation estimate.
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.
A gravitational wave burst search method based on the S transform
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
A.B. Mutiara
2011-03-01
Full Text Available Multimedia data transformation into serial stories or story board will help to reduce the consumption of storage media, indexing, sorting and searching system. Movement Oriented Method that is being developed changes the form of multimedia data into serial stories. Movement Oriented Method depends on the knowledge each actor who uses it. Different knowledge of each actor in the transformation process raises complex issues, such as the sequence, and the resulted story object that could becomes the standard. And the most fatal could be, the resulted stories does not same with the original multimedia data. To solve it, the Standard Level Knowledge (SLK in maintaining the quality of the story could be taken. SLK is the minimum knowledge that must be owned by each actor who will perform this transformation process. Quality of Service management could be applied to assess and maintain the stability and validity of the level of the each system to SLK.
Development of Method for Remaining Life Assessment of Oil-Immersed Transformer
Matsui, Tetsuro; Nakahara, Yasuo; Nishiyama, Kazuo; Urabe, Noboru; Itoh, Masayoshi
This paper presents a method for remaining life assessment of oil-immersed transformers using analyzable structured neural networks. Remaining life assessment of oil-immersed transformer is very important. Furfural method is conventionally used for such an assessment. In the furfural method, the average degree of polymerization is determined by considering the nonlinear correlation between the furfural and average degree of polymerization. The remaining life is estimated by considering the average degree of polymerization. However, a range of estimates of the remaining life is obtained when the furfural method is used, making accurate estimation difficult. The proposed method can be used to estimate the remaining life of an oil-immersed transformer accurately; this method involves analyzable structured neural networks and ensemble method. In the proposed method, not only furfural but also oil temperature, operational status, cooling type, etc., are considered. Since various factors are considered as input variables and a nonlinear model, i.e., artificial neural networks are used, accurate estimation of the remaining life has been realized. The effectiveness of the proposed method is shown by numerical simulation using actual measured data.
Numerous variance reduction techniques, such as splitting/Russian roulette, weight windows, and the exponential transform exist for improving the efficiency of Monte Carlo transport calculations. Typically, however, these methods, while reducing the variance in the problem area of interest tend to increase the variance in other, presumably less important, regions. As such, these methods tend to be not as effective in Monte Carlo calculations which require the minimization of the variance everywhere. Recently, ''Local'' Exponential Transform (LET) methods have been developed as a means of approximating the zero-variance solution. A numerical solution to the adjoint diffusion equation is used, along with an exponential representation of the adjoint flux in each cell, to determine ''local'' biasing parameters. These parameters are then used to bias the forward Monte Carlo transport calculation in a manner similar to the conventional exponential transform, but such that the transform parameters are now local in space and energy, not global. Results have shown that the Local Exponential Transform often offers a significant improvement over conventional geometry splitting/Russian roulette with weight windows. Since the biasing parameters for the Local Exponential Transform were determined from a low-order solution to the adjoint transport problem, the LET has been applied in problems where it was desirable to minimize the variance in a detector region. The purpose of this paper is to show that by basing the LET method upon a low-order solution to the forward transport problem, one can instead obtain biasing parameters which will minimize the maximum variance in a Monte Carlo transport calculation
The disposal of low-level radioactive liquid wastes at the Hanford Site near Richland, Washington, involves mixing the wastes with pozzolanic grout-forming solid blends. Checking the quality of each blend component and its mix ratio will ensure processibility of the blend and the long-term performance of the resulting waste grout. In earlier work at Hanford laboratories, Fourier transform infrared-transmission method (FTIR-TR) using KBr pellet was applied successfully in the analysis of blends consisting of cement, fly ash, and clays. This method involves time-consuming sample preparation resulting in slow turnaround for repetitive sampling. Because reflection methods do not require elaborate sample preparation, they have the potential to reduce turnaround analysis time. Neat samples may be examined making these methods attractive for quality control. This study investigates the capability of Fourier transform infrared-attenuated total reflectance method (FTIR-ATR) to analyze pozzolanic blends
Verification of Transformer Restricted Earth Fault Protection by using the Monte Carlo Method
KRSTIVOJEVIC, J. P.
2015-08-01
Full Text Available The results of a comprehensive investigation of the influence of current transformer (CT saturation on restricted earth fault (REF protection during power transformer magnetization inrush are presented. Since the inrush current during switch-on of unloaded power transformer is stochastic, its values are obtained by: (i laboratory measurements and (ii calculations based on the input data obtained by the Monte Carlo (MC simulation. To make a detailed assessment of the current transformer performance the uncertain input data for the CT model were obtained by applying the MC method. In this way, different levels of remanent flux in CT core are taken into consideration. By the generated CT secondary currents, the algorithm for REF protection based on phase comparison in time domain is tested. On the basis of the obtained results, a method of adjustment of the triggering threshold in order to ensure safe operation during transients, and thereby improve the algorithm security, has been proposed. The obtained results indicate that power transformer REF protection would be enhanced by using the proposed adjustment of triggering threshold in the algorithm which is based on phase comparison in time domain.
Bijaoui, A.
2013-03-01
The image restoration is today an important part of the astrophysical data analysis. The denoising and the deblurring can be efficiently performed using multiscale transforms. The multiresolution analysis constitutes the fundamental pillar for these transforms. The discrete wavelet transform is introduced from the theory of the approximation by translated functions. The continuous wavelet transform carries out a generalization of multiscale representations from translated and dilated wavelets. The à trous algorithm furnishes its discrete redundant transform. The image denoising is first considered without any hypothesis on the signal distribution, on the basis of the a contrario detection. Different softening functions are introduced. The introduction of a regularization constraint may improve the results. The application of Bayesian methods leads to an automated adaptation of the softening function to the signal distribution. The MAP principle leads to the basis pursuit, a sparse decomposition on redundant dictionaries. Nevertheless the posterior expectation minimizes, scale per scale, the quadratic error. The proposed deconvolution algorithm is based on a coupling of the wavelet denoising with an iterative inversion algorithm. The different methods are illustrated by numerical experiments on a simulated image similar to images of the deep sky. A white Gaussian stationary noise was added with three levels. In the conclusion different important connected problems are tackled.
无
2001-01-01
Between the transformations, witch can transform the compressible wave equation to the incompressible flow, a kind of relativity character can be found, which have the almost equal character as Lorenz time and space relation. This result leads to a new inference: incompressible wave equation with time and space structure of sonic special relativity is only different description of approximate compressible flow. This conclusion can be extended to Euler equation, and arise the interest of "compressible expression" of Maxwell equation. To study the rule of compressibility and thermodynamic character of metastructure field, a try is made by the using KamanTsian virtual gas method, this would give the relation,similar as mass and energy of special relativity theory.At first searching a transformation, witch can transform the compressible wave equation to the incompressible flow, but it is almost equal Lorenz time and space relation, So arrive to the conclusion: incompressible wave equation with approximate Lorentz transformation is only different description of compressible flow. This conclusion is expected be used to Maxwell equation, because its wave equation is also perfectly equal form. To search the rule of electromagnet and gravity field, by the using of Kaman-Tsian virtual gas method, the relation of mass and energy of relativity theory is given.``
Supersymmetric Liouville and sine-Gordon equations are studied. We write down for these models the system of linear equations for which the method of inverse scattering problem should be applicable. Expressions for an infinite set of conserved currents are explicitly given. Supersymmetric Baecklund transformations and generalized conservation laws are constructed. (author)
One-dimensional treatment of polyatomic crystals by the Laplace transform method
The one dimensional periodic potential problem is solved using the Laplace transform method and a condensed expression for the relation E x k and effective mass for one electron in a polyatomic structure is determined. Applications related to the effect of the asymmetry of the potential upon the one dimensional band structure are discussed
Yan Li-Mei
2013-01-01
Full Text Available The purpose of this paper is to extend the homotopy perturbation method to fractional heat transfer and porous media equations with the help of the Laplace transform. The fractional derivatives described in this paper are in the Caputo sense. The algorithm is demonstrated to be direct and straightforward, and can be used for many other non-linear fractional differential equations.
Alpha-rooting method of color image enhancement by discrete quaternion Fourier transform
Grigoryan, Artyom M.; Agaian, Sos S.
2014-02-01
This paper presents a novel method for color image enhancement based on the discrete quaternion Fourier transform. We choose the quaternion Fourier transform, because it well-suited for color image processing applications, it processes all 3 color components (R,G,B) simultaneously, it capture the inherent correlation between the components, it does not generate color artifacts or blending , finally it does not need an additional color restoration process. Also we introduce a new CEME measure to evaluate the quality of the enhanced color images. Preliminary results show that the α-rooting based on the quaternion Fourier transform enhancement method out-performs other enhancement methods such as the Fourier transform based α-rooting algorithm and the Multi scale Retinex. On top, the new method not only provides true color fidelity for poor quality images but also averages the color components to gray value for balancing colors. It can be used to enhance edge information and sharp features in images, as well as for enhancing even low contrast images. The proposed algorithms are simple to apply and design, which makes them very practical in image enhancement.
The unified transform method for the Sasa-Satsuma equation on the half-line.
Xu, Jian; Fan, Engui
2013-11-01
We implement the unified transform method to the initial-boundary value (IBV) problem of the Sasa-Satsuma equation on the half line. In addition to presenting the basic Riemann-Hilbert formalism, which linearizes this IBV problem, we also analyse the associated general Dirichlet to Neumann map using the so-called global relation. PMID:24204181
The unified transform method for the Sasa–Satsuma equation on the half-line
Xu, Jian; Fan, Engui
2013-01-01
We implement the unified transform method to the initial-boundary value (IBV) problem of the Sasa–Satsuma equation on the half line. In addition to presenting the basic Riemann–Hilbert formalism, which linearizes this IBV problem, we also analyse the associated general Dirichlet to Neumann map using the so-called global relation.
Wang Na; Zhang Li; Zhou Xiao'an; Jia Chuanying; Li Xia
2005-01-01
This letter exploits fundamental characteristics of a wavelet transform image to form a progressive octave-based spatial resolution. Each wavelet subband is coded based on zeroblock and quardtree partitioning ordering scheme with memory optimization technique. The method proposed in this letter is of low complexity and efficient for Internet plug-in software.
Lifting of the Vlasov-Maxwell Bracket by Lie-transform Method
Brizard, A J; Burby, J W; de Guillebon, L; Vittot, M
2016-01-01
The Vlasov-Maxwell equations possess a Hamiltonian structure expressed in terms of a Hamiltonian functional and a functional bracket. In the present paper, the transformation ("lift") of the Vlasov-Maxwell bracket induced by the dynamical reduction of single-particle dynamics is investigated when the reduction is carried out by Lie-transform perturbation methods. The ultimate goal of this work is to derive explicit Hamiltonian formulations for the guiding-center and gyrokinetic Vlasov-Maxwell equations that have important applications in our understanding of turbulent magnetized plasmas.
A gyrokinetic continuum code based on the numerical Lie transform (NLT) method
Ye, Lei; Xu, Yingfeng; Xiao, Xiaotao; Dai, Zongliang; Wang, Shaojie
2016-07-01
In this work, we report a novel gyrokinetic simulation method named numerical Lie transform (NLT), which depends on a new physical model derived from the I-transform theory. In this model, the perturbed motion of a particle is decoupled from the unperturbed motion. Due to this property, the unperturbed orbit can be computed in advance and saved as numerical tables for real-time computation. A 4D tensor B-spline interpolation module is developed and applied with the semi-Lagrangian scheme to avoid operator splitting. The NLT code is verified by the Rosenbluth-Hinton test and the linear ITG Cyclone test.
Improved Real-time Denoising Method Based on Lifting Wavelet Transform
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.
Evaluation of a method for transforming crisp values into fuzzy values
Viviane Leite Dias de Mattos
2015-12-01
Full Text Available This study analyzes a method for transforming crisp values (discrete into fuzzy values. The data comes from a quality analysis of sensory characteristics of food. It is a very common practice in the food industry. Five sets of values that were interpreted as crisp values and fuzzy values were analyzed. Friedman’s test, Wilcoxon’s test and Kendall’s coefficient were used in the statistical analysis and graphical and analytical techniques were used in the exploratory study. It was found that the metric is modified by the transformation and quite influenced by some properties of the data. The sorting by Kaufmann-Grupta’s method and by Yager’s method is similar, but it is different by Chang’s method.
Research of Adaptive Resolution Spectrum Sensing Method Based on Discrete Wavelet Packet Transform
Wei Naiqi
2013-09-01
Full Text Available Spectrum sensing is the precondition of the realization of cognitive radio. In order to achieve efficient multi-resolution spectrum sensing, and find the available spectrum hole quickly, it proposes a variable resolution adaptive frequency spectrum energy sensing method based on discrete wavelet packet transform (DWPT. The method applied hierarchical decomposition and threshold denoising characteristic of wavelet packet transform, and solved the problem of subband sort disorder in wavelet packet decomposition process; it can eliminate the influence of uncertainty noise on detection performance, effectively. It also can reduce the computational complexity according to demand of selection resolution and perception band. The simulation results and its analysis show that the proposed method has advantages of high precision, simple arithmetic and fine flexibility, etc. The method is adapted to fast sensing in the cognitive radio environment.
R. Rabenstein; Trautmann, L
2004-01-01
The functional transformation method (FTM) is a well-established mathematical method for accurate simulations of multidimensional physical systems from various fields of science, including optics, heat and mass transfer, electrical engineering, and acoustics. This paper applies the FTM to real-time simulations of transversal vibrating strings. First, a physical model of a transversal vibrating lossy and dispersive string is derived. Afterwards, this model is solved with the FTM for two cases:...
MEDICAL IMAGE DENOISE METHOD BASED ON CURVELET TRANSFORM: AN APPROACH FOR EDGE PRESERVATION
T. Janardhan Reddy
2016-01-01
In medical images noise and artifacts are presented due to the measurement techniques and instrumentation. Because of the noise present in the medical images, physicians are unable to obtain required information from the images. The paper proposes a noise reduction method for both computed tomography (CT) and magnetic resonance imaging (MRI) which fuses the Curvelet transform based method. The performance is analysed by computing Peak Signal to Noise Ratio (PSNR).The results show the proposed...
2D Satellite Image Registration Using Transform Based and Correlation Based Methods
Dr. H.B. Kekre, Dr. Tanuja K. Sarode, Ms. Ruhina B. Karani
2012-01-01
Image registration is the process of geometrically aligning one image to another image of the same scene taken from different viewpoints or by different sensors. It is a fundamental image processing technique and is very useful in integrating information from different sensors, finding changes in images taken at different times and inferring three-dimensional information from stereo images. Image registration can be done by using two matching method: transform based methods and correlation ba...
A Modeling Method for Transformer Windings Under VFTO Based on S-parameters
ZHANG Ping; WANG You-hua; NIE Xin-peng; YAN Wei-li; ZHANG Hai-jiao
2008-01-01
To study the Very Fast Transient Over-voltage(VFTO)distribution in transformer windings in gas insulated substation(GIS),a systematic methodology based on S-parameters is presented for establishing high-frequency model of transformer windings.Firstly,voltage transfer functions are derived from S-parameters which are calculated or measured from transformer windings.Secondly,voltage transfer functions are fitted with rational functions by the vector fitting method and then the rational transfer functions are order-reduced by optimal Pade-approximation algorithm.Lastly,the resultant voltage transfer functions are synthesized by network technology.Computational results are consistent with simulation results of Electromagnetic Transient Program(EMTP)and confirm the feasibility and validity of proposed methodology.
A complex guided spectral transform Lanczos method for studying quantum resonance states
A complex guided spectral transform Lanczos (cGSTL) algorithm is proposed to compute both bound and resonance states including energies, widths and wavefunctions. The algorithm comprises of two layers of complex-symmetric Lanczos iterations. A short inner layer iteration produces a set of complex formally orthogonal Lanczos (cFOL) polynomials. They are used to span the guided spectral transform function determined by a retarded Green operator. An outer layer iteration is then carried out with the transform function to compute the eigen-pairs of the system. The guided spectral transform function is designed to have the same wavefunctions as the eigenstates of the original Hamiltonian in the spectral range of interest. Therefore the energies and/or widths of bound or resonance states can be easily computed with their wavefunctions or by using a root-searching method from the guided spectral transform surface. The new cGSTL algorithm is applied to bound and resonance states of HO, and compared to previous calculations
Design parameter based method of partial discharge detection and location in power transformers
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. .
HASHEM SABERI NAJAFI
2016-07-01
Full Text Available Generalized differential transform method (GDTM is a powerful method to solve the fractional differential equations. In this paper, a new fractional model for systems with single degree of freedom (SDOF is presented, by using the GDTM. The advantage of this method compared with some other numerical methods has been shown. The analysis of new approximations, damping and acceleration of systems are also described. Finally, by reducing damping and analysis of the errors, in one of the fractional cases, we have shown that in addition to having a suitable solution for the displacement close to the exact one, the system enjoys acceleration once crossing the equilibrium point.
Rahmani Faramarz; Golshani Mehdi; Sarbishei Mohsen
2016-04-01
In this paper we shall argue that conformal transformations give some new aspects to a metric and changes the physics that arises from the classical metric. It is equivalent to adding a new potential to relativistic Hamilton–Jacobi equation. We start by using conformal transformations on a metric and obtain modified geodesics. Then, we try to show that extra terms in the modified geodesics are indications of a background force. We obtain this potential by using variational method. Then, we see that this background potential is the same as the Bohmian non-local quantum potential. This approach gives a method stronger than Bohm’s original method in deriving Bohmian quantumpotential. We do not use any quantum mechanical postulates in this approach.
Fourier transform method for sensitivity analysis in coal fired power plant
This work proposes a Fourier transform method to determine the sensitivities associated with a real coal power plant using a Rankine cycle. Power demand determines the plant revenue and is supposed to be the most important parameter to be accurately measured, and this hypothesis is at the center of this study. The results confirm that under full design load, variables such as steam pressure, temperature and mass flow rate are closely dependent on power demand, though overall thermal efficiency is more sensitive to boiler efficiency. Partial load simulation shows that the overall thermal efficiency remains strongly dependent on the boiler parameters, but other operational variables such as steam temperature at the turbine outlet changes its sensitivity according to the load. The results from the Fourier transform method are in good agreement with those determined by classical differential and Monte Carlo methods. However, the Fourier transform method requires only a single run, providing major savings in computational time as compared to the Monte Carlo method, a major advantage for analysis of power systems whether operating under full or partial load
Mehfuza Holia
2009-11-01
Full Text Available In computer vision system sets of data acquired by sampling of the same sceneor object at different times or from different perspectives, will be in differentcoordinate systems. Image registration is the process of transforming thedifferent sets of data into one coordinate system. Registration is necessaryin order to be able to compare or integrate the data obtained from differentmeasurements such as different view points, different times, different sensorsetc. Image Registration is an important problem and a fundamental task in imageprocessing technique. This paper presents an algorithm for recovering translationparameter from two images that differ by Rotation, Scaling, Transformation andRotation-scale-Translation (RST also known as similarity transformation. It is atransformation expressed as a pixel mapping function that maps a referenceimage into a pattern image. The images having rotational, scaling, translationdifferences are registered using correlation with Nelder-mead method for functionminimization. The algorithm finds the correlation between original image andsensed images. It applies the transformation parameters on sensed images sothat maximum correlation between original image and sensed images areachieved. Simulation results (Using Matlab on images show the Performancesof the method.
Cinicioglu Esma Nur
2014-01-01
Full Text Available Dempster−Shafer belief function theory can address a wider class of uncertainty than the standard probability theory does, and this fact appeals the researchers in operations research society for potential application areas. However, the lack of a decision theory of belief functions gives rise to the need to use the probability transformation methods for decision making. For representation of statistical evidence, the class of consonant belief functions is used which is not closed under Dempster’s rule of combination but is closed under Walley’s rule of combination. In this research, it is shown that the outcomes obtained using both Dempster’s and Walley’s rules do result in different probability distributions when pignistic transformation is used. However, when plausibility transformation is used, they do result in the same probability distribution. This result shows that the choice of the combination rule and probability transformation method may have a significant effect on decision making since it may change the choice of the decision alternative selected. This result is illustrated via an example of missile type identification.
A new stationary gridline artifact suppression method based on the 2D discrete wavelet transform
Tang, Hui, E-mail: corinna@seu.edu.cn [Laboratory of Image Science and Technology, School of Computer Science and Engineering, Southeast University, Nanjing 210096 (China); Key Laboratory of Computer Network and Information Integration (Southeast University), Ministry of Education, Nanjing 210000 (China); Centre de Recherche en Information Biomédicale sino-français, Laboratoire International Associé, Inserm, Université de Rennes 1, Rennes 35000 (France); Southeast University, Nanjing 210000 (China); Tong, Dan; Dong Bao, Xu [Laboratory of Image Science and Technology, School of Computer Science and Engineering, Southeast University, Nanjing 210096 (China); Dillenseger, Jean-Louis [INSERM, U1099, Rennes F-35000 (France); Université de Rennes 1, LTSI, Rennes F-35000 (France); Centre de Recherche en Information Biomédicale sino-français, Laboratoire International Associé, Inserm, Université de Rennes 1, Rennes 35000 (France); Southeast University, Nanjing 210000 (China)
2015-04-15
Purpose: In digital x-ray radiography, an antiscatter grid is inserted between the patient and the image receptor to reduce scattered radiation. If the antiscatter grid is used in a stationary way, gridline artifacts will appear in the final image. In most of the gridline removal image processing methods, the useful information with spatial frequencies close to that of the gridline is usually lost or degraded. In this study, a new stationary gridline suppression method is designed to preserve more of the useful information. Methods: The method is as follows. The input image is first recursively decomposed into several smaller subimages using a multiscale 2D discrete wavelet transform. The decomposition process stops when the gridline signal is found to be greater than a threshold in one or several of these subimages using a gridline detection module. An automatic Gaussian band-stop filter is then applied to the detected subimages to remove the gridline signal. Finally, the restored image is achieved using the corresponding 2D inverse discrete wavelet transform. Results: The processed images show that the proposed method can remove the gridline signal efficiently while maintaining the image details. The spectra of a 1D Fourier transform of the processed images demonstrate that, compared with some existing gridline removal methods, the proposed method has better information preservation after the removal of the gridline artifacts. Additionally, the performance speed is relatively high. Conclusions: The experimental results demonstrate the efficiency of the proposed method. Compared with some existing gridline removal methods, the proposed method can preserve more information within an acceptable execution time.
A new stationary gridline artifact suppression method based on the 2D discrete wavelet transform
Purpose: In digital x-ray radiography, an antiscatter grid is inserted between the patient and the image receptor to reduce scattered radiation. If the antiscatter grid is used in a stationary way, gridline artifacts will appear in the final image. In most of the gridline removal image processing methods, the useful information with spatial frequencies close to that of the gridline is usually lost or degraded. In this study, a new stationary gridline suppression method is designed to preserve more of the useful information. Methods: The method is as follows. The input image is first recursively decomposed into several smaller subimages using a multiscale 2D discrete wavelet transform. The decomposition process stops when the gridline signal is found to be greater than a threshold in one or several of these subimages using a gridline detection module. An automatic Gaussian band-stop filter is then applied to the detected subimages to remove the gridline signal. Finally, the restored image is achieved using the corresponding 2D inverse discrete wavelet transform. Results: The processed images show that the proposed method can remove the gridline signal efficiently while maintaining the image details. The spectra of a 1D Fourier transform of the processed images demonstrate that, compared with some existing gridline removal methods, the proposed method has better information preservation after the removal of the gridline artifacts. Additionally, the performance speed is relatively high. Conclusions: The experimental results demonstrate the efficiency of the proposed method. Compared with some existing gridline removal methods, the proposed method can preserve more information within an acceptable execution time
The data treatment results of the small angle scattering from lamellar and cylindrical particles by indirect transformation method has been geometrically analized. Presented the theory of small angle scattering from lamellar and cylindrical particles that gives the cross section scattering function in the reciprocal space and the distance distribution function in the real space. Also discussed the features of the indirect transformation method compare to the conventional method that is the direct transformation method. Presented the data treatment results of the cylindrical particles cross section scattering from the data treatment results of the cylindrical particles scattering. The calculation of the parameters from the two of data sets give values of cross section intensity at zero angle It (0) = 0.53640, and Ic (0) = 151.51, cross sections of radius of gyration Rt = 11.461oA and Rc = 13.908oA and the maximum diameter of the cross sections Dt (max) = 40oA and Dc (max) = 40oA of lamellar and cylindrical particles, respectively. (author)
A Novel Multi-Focus Image Fusion Method Based on Dual-Tree Shearlet Transform
Chang Duan
2015-06-01
Full Text Available In this paper, a multi-focus image fusion method based on Dual-Tree Compactly Supported Shearlet Transform (DT CSST and Direction Decision Map (DDM is proposed. DT CSST is a shift invariant modification of conventional Compactly Supported Shearlet Transform (CSST. Based on the mitigation of shift variance of CSST in DT CSST, a clearer fused image could be acquired through the General Image Fusion (GIF method, and this image is called the initial fused image in this paper. The decision map is determined by the similarity of the initial fused image and the source images. The generation algorithm of the decision map in this paper takes advantage of the directional nature of DT CSST: every direction of the transform generates an initial directional decision map and then yields the final map through vote and smooth steps. This scheme is called DDM in this paper. The proposed method is evaluated by four groups of standard images. The results show that the proposed method is able to improve the quality indices compared with two algorithms which have excellent quality indices.
Kamalian, Morteza; Prilepsky, Jaroslaw E; Le, Son Thai; Turitsyn, Sergei K
2016-08-01
In this work, we introduce the periodic nonlinear Fourier transform (PNFT) method as an alternative and efficacious tool for compensation of the nonlinear transmission effects in optical fiber links. In the Part I, we introduce the algorithmic platform of the technique, describing in details the direct and inverse PNFT operations, also known as the inverse scattering transform for periodic (in time variable) nonlinear Schrödinger equation (NLSE). We pay a special attention to explaining the potential advantages of the PNFT-based processing over the previously studied nonlinear Fourier transform (NFT) based methods. Further, we elucidate the issue of the numerical PNFT computation: we compare the performance of four known numerical methods applicable for the calculation of nonlinear spectral data (the direct PNFT), in particular, taking the main spectrum (utilized further in Part II for the modulation and transmission) associated with some simple example waveforms as the quality indicator for each method. We show that the Ablowitz-Ladik discretization approach for the direct PNFT provides the best performance in terms of the accuracy and computational time consumption. PMID:27505799
Tavares, Paulo J.; Vaz, Mário A. P.
2013-03-01
Gradient range and spatial resolution in Fourier Transform Profilometry depend on the size of the filter window in reciprocal space. The proposed methods to date for the elimination of the fundamental frequency and enlargement of the filter window are either too computationally complex or depend on the possibility of using two frames, thus disabling the method's ability to cope with dynamic situations and subjecting the results to possible intensity changes between the two frame acquisitions. This article describes a simple method for using a single crossed fringe pattern to accomplish that objective, greatly improving the previously reported technique, whilst retaining its main advantages.
Burhan Ergen
2014-01-01
Full Text Available This paper proposes two edge detection methods for medical images by integrating the advantages of Gabor wavelet transform (GWT and unsupervised clustering algorithms. The GWT is used to enhance the edge information in an image while suppressing noise. Following this, the k-means and Fuzzy c-means (FCM clustering algorithms are used to convert a gray level image into a binary image. The proposed methods are tested using medical images obtained through Computed Tomography (CT and Magnetic Resonance Imaging (MRI devices, and a phantom image. The results prove that the proposed methods are successful for edge detection, even in noisy cases.
Study of organic N transformation in red soils by 15N tracer method
YeQing－Fu; ZhangQin－Zheng; 等
1997-01-01
Uniformly 15N-labelled ryegrass was used to investigate NH4+-production,microbial transformation and humification of organic N in two types of red soils by incubating the soils amended with labelled material.The results showed that there was little significant difference in biomass N transformation in the tested solis between 15N tracer method and conventional method,but the amount of NH4++-N released form the ryegrass in the clayey soil than in the sandy soil at all sampling time .By 120d of incubation,humified N was less than 10% of the amount of the applied N in two types of red soils and the amount of residual N in the clayey red soil was obviously higher than that in the sandy red soil.
S. hajiaghasi
2014-07-01
Full Text Available In recent years with notice increase reliability in power system and Intelligent Systems and also notice that transformers are one of the main part of the transmission and distribution systems, online monitoring of these equipment in power system are require. In this paper, a new method for online interturn fault detection base on leakage flux in power transformer are propose. When an interturn fault occur the symmetry of flux destruction and leakage flux increase or decrease and for various location and severity of fault leakage flux is different and it can be used for fault detection. In this paper for measure these flux we using search coils that mounted on HV winding. To fault detection and classify we using probabilistic neural network. and for decrease the information volume PCA is used. The simulation results are compare and verified with experimental result and show that this propose method is very good.
Kaneko, Tak
2008-01-01
Context: Fourier transform (or lag) correlators in radio interferometers can serve as an efficient means of synthesising spectral channels. However aliasing corrupts the edge channels so they usually have to be excluded from the data set. In systems with around 10 channels, the loss in sensitivity can be significant. In addition, the low level of residual aliasing in the remaining channels may cause systematic errors. Moreover, delay errors have been widely reported in implementations of broadband analogue correlators and simulations have shown that delay errors exasperate the effects of aliasing. Aims: We describe a software-based approach that suppresses aliasing by oversampling the cross-correlation function. This method can be applied to interferometers with individually-tracking antennas equipped with a discrete path compensator system. It is based on the well-known property of interferometers where the drift scan response is the Fourier transform of the source's band-limited spectrum. Methods: In this p...
davood domiri ganji
2014-10-01
Full Text Available The differential transform and least square are analytical methods for solving differential equations. In this article, two-Dimensional Differential Transform Method (2D DTM and Least Square Method (LSM are applied to obtaining the analytic solution of the two- dimensional non- linear wave equations. We demonstrate that the differential transform method and least square are very effective and convenient for achieving the analytical solutions of linear or nonlinear partial differential equations. Also, three examples are given to demonstrate the exactness of the methods. Results of these methods are compared with the exact solution.
Improved Method of Generating Bit Reserved Numbers for Calculating Fast Fourier Transform
T. Suresh
1996-10-01
Full Text Available Fast Fourier Transform (FFT is an important tool required for signal processing in defence applications. This paper reports an improved method for generating bit reversed numbers needed in calculating FFT using radix-2. The refined algorithm takes advantage of some features of the bit reversed numbers, using intermediate array for storage and improved procedure for calculating base values required when generating bit reversed numbers.
Evaluation of software using the finite element method by simulating transformers and inductors
Larsson, Jenny; Håkansson, David
2011-01-01
In this bachelor thesis several software, capable of calculating andsimulating complex problems concerning the power losses in inductors andtransformers with the finite element method, have been evaluated and used tosolve test cases provided by the commissioner. The software have been evaluatedwith respect to several requirements stated by the commissioner.The aim is to be able to simulate power losses and inductance levels in complexdesigns of inductors and transformers. By reading the manua...
Power-law behaviour evaluation from foreign exchange market data using a wavelet transform method
Numerous studies in the literature have shown that the dynamics of many time series including observations in foreign exchange markets exhibit scaling behaviours. A simple new statistical approach, derived from the concept of the continuous wavelet transform correlation function (WTCF), is proposed for the evaluation of power-law properties from observed data. The new method reveals that foreign exchange rates obey power-laws and thus belong to the class of self-similarity processes.
Zhang, Yu-xin; Cheng, Zhi-feng; Xu, Zheng-ping; Bai, Jing
2015-01-01
In order to solve the problems such as complex operation, consumption for the carrier gas and long test period in traditional power transformer fault diagnosis approach based on dissolved gas analysis (DGA), this paper proposes a new method which is detecting 5 types of characteristic gas content in transformer oil such as CH4, C2H2, C2H4, C2H6 and H2 based on photoacoustic Spectroscopy and C2H2/C2H4, CH4/H2, C2H4/C2H6 three-ratios data are calculated. The support vector machine model was constructed using cross validation method under five support vector machine functions and four kernel functions, heuristic algorithms were used in parameter optimization for penalty factor c and g, which to establish the best SVM model for the highest fault diagnosis accuracy and the fast computing speed. Particles swarm optimization and genetic algorithm two types of heuristic algorithms were comparative studied in this paper for accuracy and speed in optimization. The simulation result shows that SVM model composed of C-SVC, RBF kernel functions and genetic algorithm obtain 97. 5% accuracy in test sample set and 98. 333 3% accuracy in train sample set, and genetic algorithm was about two times faster than particles swarm optimization in computing speed. The methods described in this paper has many advantages such as simple operation, non-contact measurement, no consumption for the carrier gas, long test period, high stability and sensitivity, the result shows that the methods described in this paper can instead of the traditional transformer fault diagnosis by gas chromatography and meets the actual project needs in transformer fault diagnosis. PMID:25993810
Developing de-noising methods for ultrasonic NDT based on wavelet transform and adaptive filtering
Digital signal processing methods based on the advanced wavelet transform and adaptive filtering were developed to deal with the problem of material's grain noise in ultrasonic Non Destructive Testing applications. The developed methods were implemented in lab View (Laboratory Virtual Instruments Engineering Workbench) programming environment. The experimental ultrasonic signals were obtained by inspecting stainless steel blocks with side-drilled holes, and carbon steel welded plates contain three types of welding flaws: root crack, centerline crack and slag inclusion. The simulations were carried out using CIVA Non Destructive Evaluation modeling software. Wavelet transform has introduced innovative changes in different fields of science and engineering. One of its important applications is in de-noising of signals and images. Wavelet packet is an efficient de-noising method, which has been used for ultrasonic Non Destructive Testing signals de-noising, wavelet packet is generalizations of the discrete wavelet transform. The first part of this research proposes the use of the un decimated wavelet transform in implementing wavelet packets to overcome the limitation of the shift variance encountered in discrete wavelet transform. Simulations and experiments were carried out on flaw's echo signals contaminated with material's grain noise, various wavelet transform processing parameters were investigated, including the number of decomposition levels, analyzing wavelets, and threshold setting. The results showed superior de-noising effect of the developed method over the conventional one. In the second part of the research, improvements are proposed to the multi-stage adaptive filter, which has been reported in a previous study as an advanced adaptive noise cancellation system for ultrasonic None Destructive Testing applications. The multi stage adaptive filter is limited by the slow convergence speed of the least-mean-squares algorithm as well as
Bulbul AHMED
2011-11-01
Full Text Available Arabidopsis thaliana is a small flowering plant belonging to the Brassicaceae family, which is adopted as a model plant for genetic research. Agrobacterium tumifaciensmediated transformation method for A. thaliana ecotype Bangladesh was established. Leaf discs of A. thaliana were incubated with A. tumefaciens strain LBA4404 containing chimeric nos. nptII. nos and intron-GUS genes. Following inoculation and co-cultivation, leaf discs were cultured on selection medium containing 50 mg/l kanamycin + 50 mg/l cefotaxime + 1.5 mg/l NAA and kanamycin resistant shoots were induced from the leaf discs after two weeks. Shoot regeneration was achieved after transferring the tissues onto fresh medium of the same combination. Finally, the shoots were rooted on MS medium containing 50 mg/l kanamycin. Incorporation and expression of the transgenes were confirmed by PCR analysis. Using this protocol, transgenic A. thaliana plants can be obtained and indicates that genomic transformation in higher plants is possible through insertion of desired gene. Although Agrobacterium mediated genetic transformation is established for A. thaliana, this study was the conducted to transform A. thaliana ecotype Bangladesh.
A method for energy and exergy analyses of product transformation processes in industry
After a literature survey enabling the determination of the advantages and drawbacks of existing methods of assessment of the potential energy gains of an industrial site, this research report presents a newly developed method, named Energy and Exergy Analysis of Transformation Processes (or AEEP for Analyse energetique et exergetique des procedes de transformation), while dealing with actual industrial operations, in order to demonstrate the systematic character of this method. The different steps of the method are presented and detailed, one of them, the process analysis, being critical for the application of the developed method. This particular step is then applied to several industrial unitary operations in order to be a base for future energy audits in the concerned industry sectors, as well as to demonstrate its generic and systematic character. The method is the then applied in a global manner to a cheese manufacturing plant, all the different steps of the AEEP being applied. The author demonstrates that AEEP is a systematic method and can be applied to all energy audit levels, moreover to the lowest levels which have a relatively low cost
A NEW METHOD OF BAD POINTS ELIMINATION BASED ON HOUGH TRANSFORM
Chen Su; Lin Jiayu
2010-01-01
In experimental tests,besides data in range of allowable error,the experimenters usually get some unexpected wrong data called bad points. In usual experimental data processing,the method of bad points exclusion based on automatic programming is seldom taken into consideration by researchers. This paper presents a new method to reject bad points based on Hough transform,which is modified to save computational and memory consumptions. It is fit for linear data processing and can be extended to process data that is possible to be transformed into and from linear form; curved lines,which can be effectively detected by Hough transform. In this paper,the premise is the distribution of data,such as linear distribution and exponential distribution,is predetermined. Steps of the algorithm start from searching for an approximate curve line that minimizes the sum of parameters of data points. The data points,whose parameters are above a self-adapting threshold,will be deleted. Simulation experiments have manifested that the method proposed in this paper performs efficiently and robustly.
Yu Dejie; Cheng Junsheng; Yang Yu
2005-01-01
Based upon empirical mode decomposition (EMD) method and Hilbert spectrum, a method for fault diagnosis of roller bearing is proposed. The orthogonal wavelet bases are used to translate vibration signals of a roller bearing into time-scale representation, then, an envelope signal can be obtained by envelope spectrum analysis of wavelet coefficients of high scales. By applying EMD method and Hilbert transform to the envelope signal, we can get the local Hilbert marginal spectrum from which the faults in a roller bearing can be diagnosed and fault patterns can be identified. Practical vibration signals measured from roller bearings with out-race faults or inner-race faults are analyzed by the proposed method. The results show that the proposed method is superior to the traditional envelope spectrum method in extracting the fault characteristics of roller bearings.
Nanato, N.; Kobayashi, Y.
AC high temperature superconducting (HTS) coils have been developed for transformers, motors and so on. Quench detection and protection system are essential for safety operations of the AC HTS facilities. The balance voltage method is universally used for the quench detection and protection, however especially for AC operations, the method has risks in terms of high voltage sparks. Because the method needs a voltage tap soldered to a midpoint of the coil winding and the AC HTS facilities generally operate at high voltages and therefore high voltage sparks may occur at the midpoint with no insulation. We have proposed the active power method for the quench detection and protection. The method requires no voltage tap on the midpoint of the coil winding and therefore it has in-built effectiveness for the AC HTS facilities. In this paper, we show that the method can detect the quench in an HTS transformer and moreover our proposed quench protection circuits which consist of thyristors are simple and useful for the AC HTS facilities.
Finite volume method for the Black-Scholes equation transformed on finite interval
Valkov, R.
2012-11-01
In this paper, we present a fitted FVM for the degenerate at the two ends parabolic equation, derived from the Black-Scholes equation after a transformation to a finite interval. For the case of European options we describe a fully discretization of the vertical method of lines, where the spatial discretization is formulated as a Petrov-Galerkin FEM. We show that the method is O(h) convergent and monotone. Numerical experiments are presented to verify the theoretical results. Experiments on a power-graded mesh demonstrate higher accuracy.
Higher-order schemes for the Laplace transformation method for parabolic problems
Douglas, C.
2011-01-01
In this paper we solve linear parabolic problems using the three stage noble algorithms. First, the time discretization is approximated using the Laplace transformation method, which is both parallel in time (and can be in space, too) and extremely high order convergent. Second, higher-order compact schemes of order four and six are used for the the spatial discretization. Finally, the discretized linear algebraic systems are solved using multigrid to show the actual convergence rate for numerical examples, which are compared to other numerical solution methods. © 2011 Springer-Verlag.
Analysis of the characteristics of gastrointestinal motility based on Hilbert-Huang transform method
Huang Biao; Yan Guozheng
2008-01-01
Pressure activity data as an important index of gastrointestinal (GI) motility can be obtained from the wireless radiotelemetry capsule. The Hilbert-Huang transform (HHT) method, which is more effective to process non-stationary signal, is proposed to identify the characteristics of GI motility. We decompose the pressure activity data into intrinsic mode functions (IMFs),calculate the Hilbert marginal spectrum and attain the peristalsis characteristics of GI tract. The IMFs represent the peristalses modes of GI tract activity embedded in the pressure data. The time-varying characteristic of the method suggests that the HHT is suitable to accommodate other non-stationary biomedical data analysis.
Exact and approximate interior corner problem in neutron diffusion by integral transform methods
Bareiss, E.H.; Chang, K.S.J.; Constatinescu, D.A.
1976-09-01
The mathematical solution of the neutron diffusion equation exhibits singularities in its derivatives at material corners. A mathematical treatment of the nature of these singularities and its impact on coarse network approximation methods in computational work is presented. The mathematical behavior is deduced from Green's functions, based on a generalized theory for two space dimensions, and the resulting systems of integral equations, as well as from the Kontorovich--Lebedev Transform. The effect on numerical calculations is demonstrated for finite difference and finite element methods for a two-region corner problem.
It is shown that advantage can be taken of the structure of compartment models of the environment to develop an appropriate Laplace transform solution method. Such models can often be divided into a number of sub-models, and providing the number of compartments in each sub-model does not exceed about 10, the computational time required is not excessive. Larger models can often be reduced to systems of this size by taking account of those parts of the environment where local equilibrium is rapidly attained. For many situations, particularly where decay chains of radionuclides are considered, this method can actually show significant time savings over time-stepping solutions. (author)
Mehrabi, Saeed; Mohammadi, Iman; Kunjan, Kislaya; Kharrazi, Hadi
2013-01-01
Large datasets may contain redundant data. Variable selection methods that select most relevant variables in the data set, fail to consider the interaction between the variables. Data transformation methods are used to transfer the original data to a new dimension and capture the most significant information within the data set. The data set used in this study was based on 45 clinical variables collected from 697 patients diagnosed as either having myocardial infarction (MI) or not. Principal component analysis (PCA) and independent component analysis (ICA) were applied prior to classification of patients to MI or Non-MI groups using support vector machines (SVM). PMID:23920977
Hoang, Nguyen Tien; Koike, Katsuaki
2015-10-01
It has been generally accepted that hyperspectral remote sensing is more effective and provides greater accuracy than multispectral remote sensing in many application fields. EO-1 Hyperion, a representative hyperspectral sensor, has much more spectral bands, while Landsat data has much wider image scene and longer continuous space-based record of Earth's land. This study aims to develop a new method, Pseudo-Hyperspectral Image Synthesis Algorithm (PHISA), to transform Landsat imagery into pseudo hyperspectral imagery using the correlation between Landsat and EO-1 Hyperion data. At first Hyperion scene was precisely pre-processed and co-registered to Landsat scene, and both data were corrected for atmospheric effects. Bayesian model averaging method (BMA) was applied to select the best model from a class of several possible models. Subsequently, this best model is utilized to calculate pseudo-hyperspectral data by R programming. Based on the selection results by BMA, we transform Landsat imagery into 155 bands of pseudo-hyperspectral imagery. Most models have multiple R-squared values higher than 90%, which assures high accuracy of the models. There are no significant differences visually between the pseudo- and original data. Most bands have Pearson's coefficients coefficients < 0.93 like outliers in the data sets. In a similar manner, most Root Mean Square Error values are considerably low, smaller than 0.014. These observations strongly support that the proposed PHISA is valid for transforming Landsat data into pseudo-hyperspectral data from the outlook of statistics.
A Novel Color Microscope Image Enhancement Method Based on HSV Color Space and Curvelet Transform
Chuancheng Ren
2012-11-01
Full Text Available A new method which is suitable for enhancing the color microscopic image quality based on HSV color space and curvelet transform is presented in this paper. The color microscopic image is firstly divided into hue, saturation and value components from RGB color space to HSV color space through the color space conversion. The value component is decomposed by the curvelet transform. A modulus square function and a linear gain operator are applied to the high frequency curvelet coefficients to reduce noise and weight the detail. Then, the processed curvelet coefficients are reconstructed in order to obtain the enhanced value component by inverse wavelet transform. The saturation component is enhanced by adaptive histogram equalization. The enhanced value and saturation components together with unchanged hue component are finally converted back RGB color space. The experimental results show that the proposed method effectively enhances the color microscopic image which is better to reduce noise and render the clarity and colorfulness of the original image.
Wavelet transform and real-time learning method for myoelectric signal in motion discrimination
Liu Haihua; Chen Xinhao; Chen Yaguang [College of Electronics and Information Engineering, South-Central University for Nationalities, Wuhan (China)
2005-01-01
This paper discusses the applicability of the Wavelet transform for analyzing an EMG signal and discriminating motion classes. In many previous works, researchers have dealt with steady EMG and have proposed suitable analyzing methods for the EMG, for example FFT and STFT. Therefore, it is difficult for the previous approaches to discriminate motions from the EMG in the different phases of muscle activity, i.e., pre-activity, in activity, postactivity phases, as well as the period of motion transition from one to another. In this paper, we introduce the Wavelet transform using the Coiflet mother wavelet into our real-time EMG prosthetic hand controller for discriminating motions from steady and unsteady EMG. A preliminary experiment to discriminate three hand motions from four channel EMG in the initial pre-activity and in activity phase is carried out to show the effectiveness of the approach. However, future research efforts are necessary to discriminate more motions much precisely.
Wavelet transform and real-time learning method for myoelectric signal in motion discrimination
This paper discusses the applicability of the Wavelet transform for analyzing an EMG signal and discriminating motion classes. In many previous works, researchers have dealt with steady EMG and have proposed suitable analyzing methods for the EMG, for example FFT and STFT. Therefore, it is difficult for the previous approaches to discriminate motions from the EMG in the different phases of muscle activity, i.e., pre-activity, in activity, postactivity phases, as well as the period of motion transition from one to another. In this paper, we introduce the Wavelet transform using the Coiflet mother wavelet into our real-time EMG prosthetic hand controller for discriminating motions from steady and unsteady EMG. A preliminary experiment to discriminate three hand motions from four channel EMG in the initial pre-activity and in activity phase is carried out to show the effectiveness of the approach. However, future research efforts are necessary to discriminate more motions much precisely
Fedorenko, Sergei V
2011-01-01
A novel method for computation of the discrete Fourier transform over a finite field with reduced multiplicative complexity is described. If the number of multiplications is to be minimized, then the novel method for the finite field of even extension degree is the best known method of the discrete Fourier transform computation. A constructive method of constructing for a cyclic convolution over a finite field is introduced.
YANG Zhou; ZHU Yunpeng; REN Hongrui; ZHANG Yimin
2015-01-01
Reliability allocation of computerized numerical controlled(CNC) lathes is very important in industry. Traditional allocation methods only focus on high-failure rate components rather than moderate failure rate components, which is not applicable in some conditions. Aiming at solving the problem of CNC lathes reliability allocating, a comprehensive reliability allocation method based on cubic transformed functions of failure modes and effects analysis(FMEA) is presented. Firstly, conventional reliability allocation methods are introduced. Then the limitations of direct combination of comprehensive allocation method with the exponential transformed FMEA method are investigated. Subsequently, a cubic transformed function is established in order to overcome these limitations. Properties of the new transformed functions are discussed by considering the failure severity and the failure occurrence. Designers can choose appropriate transform amplitudes according to their requirements. Finally, a CNC lathe and a spindle system are used as an example to verify the new allocation method. Seven criteria are considered to compare the results of the new method with traditional methods. The allocation results indicate that the new method is more flexible than traditional methods. By employing the new cubic transformed function, the method covers a wider range of problems in CNC reliability allocation without losing the advantages of traditional methods.
Binary encoding method to encrypt Fourier-transformed information of digital images
Lin, Kuang Tsan
2009-02-01
An encoding method is used to encrypt the Fourier-transformed information of a hidden (covert) digital image in an overt image, while the Fourier-transformed information must be encoded with binary codes. All of the pixels in an overt image are classified into five groups that are called identification, type, tracing, dimension, and information codes. Identification codes are used to judge if the overt image contains codes that belong to the proposed encoding method or not; type codes are used to judge the encoding type; tracing codes are used to judge the encoding trace; dimension codes are used to judge the size of the hidden information; and information codes are used to decode the hidden information. Applying the proposed encoding method is rather easy, and host images corresponding to overt images are not needed for decoding work. The experiment has demonstrated four types of encoding for the proposed encoding method to reconstruct covert images without any distortion or only with a little distortion.
C.S. Manikandababu
2015-03-01
Full Text Available The widely used standard for medical image storage and transmission is named as Digital Imaging and Communication in Medicine (DICOM. In every field of medicine including diagnosis, treatment, and research, medical images that are obtained as the outputs of the techniques such as the Computerized Tomography (CT, magnetic resonance (MR, digital subtraction angiography (DSA and Ultrasonography (US are saved as DICOM format. Network sharing of these larger sized radiology images require large bandwidth. Hence before transferring, compression of such larger image files is necessary for easy and faster communication even with lower bandwidth. Huge amount of data either in multidimensional or multiresolution form is been created as a result of medical information. This makes the following steps like retrieval, efficient storage, management, and transmission of these data a complex process. This complexity could be reduced by compressing the medical data without any loss. Many methods have been proposed so far for compression of the large DICOM images, however with some limitations. Thus, specific methods to overcome the limitations like reducing the noise of MSE error signal and improving the PSNR value results in the medical images are to be proposed for the study. One such method is referred as Hybrid Weibull Probability Density Function based Continuous Wavelet based controulet transform (WPDF-CWBCT that helps for compression of medical images without any data loss and also for improving the PSNR and reducing the MSE of the signal. The directional filter banks are being applied by initializing using the wavelet transform such that the image coding scheme is maintained based on the proposed transform. WPDF-CWBCT also uses a new set partitioning in hierarchical trees by employing a sorting method (SPIHT algorithm that provided an embedded code. In this method, the diagnostics capabilities are not compromised to ensure the better performance of image
Sunday O. Edeki; Olabisi O. Ugbebor; Owoloko, Enahoro A.
2015-01-01
In this paper, a proposed computational method referred to as Projected Differential Transformation Method (PDTM) resulting from the modification of the classical Differential Transformation Method (DTM) is applied, for the first time, to the Black–Scholes Equation for European Option Valuation. The results obtained converge faster to their associated exact solution form; these easily computed results represent the analytical values of the associated European call options, and the same algor...
2010-01-01
... 10 Energy 3 2010-01-01 2010-01-01 false Uniform Test Method for Measuring the Energy Consumption of Distribution Transformers A Appendix A to Subpart K of Part 431 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Distribution Transformers Pt. 431, Subpt. K, App. A Appendix...
A method for the large scale isolation of high transformation efficiency fungal genomic DNA.
Zhang, D; Yang, Y; Castlebury, L A; Cerniglia, C E
1996-12-01
A procedure for isolation of genomic DNA from the zygomycete Cunninghamella elegans and other filamentous fungi and yeasts is reported. This procedure involves disruption of cells by grinding using dry ice, removal of polysaccharides using cetyltrimethylammonium bromide and by phenol extractions, and precipitation of DNA with isopropanol at room temperature. The isolation method produced large scale (approximate 1 mg DNA/5 g wet cells) and highly purified high molecular mass DNA. Sau3AI partially digested DNA showed high transformation efficiency (> 10(6)/100 ng DNA) when ligated to ZAP-express lambda vector. PMID:8961565
Xueyong Liu; Mei Li; Wei Tang; Shichao Wang; Xiong Wu
2014-01-01
Infrasound is a type of low frequency signal that occurs in nature and results from man-made events, typically ranging in frequency from 0.01 Hz to 20 Hz. In this paper, a classification method based on Hilbert-Huang transform (HHT) and support vector machine (SVM) is proposed to discriminate between three different natural events. The frequency spectrum characteristics of infrasound signals produced by different events, such as volcanoes, are unique, which lays the foundation for infrasound ...
TDA method application to austenite transformation in nodular cast iron with carbides assessment
G. Gumienny
2011-01-01
In this paper the possibility of TDA method using to austenite transformation in nodular cast iron with carbides assessment is presented. Studies were conducted on cast iron with about 2% molybdenum and 0,70% to 4,50% nickel. On diagrams, where TDA curves are pre- sented, on time axis a logarithmic scale was applied. It has not been used up to now. It was found, that during cooling and crystallization of cast iron in TDA probe, on the derivative curve there is a slight thermal effect from aus...
Yeletskikh, I V
2007-01-01
Applying the unitary clothing transformation method in the model of charged spinless nucleons and neutral mesons interacting via the three-linear Yukawa-type coupling, the expression for the charge shift in the third order in the coupling constant is derived. Being determined off the energy shell, the ex-pression can be reduced on the energy shell to the explicitly covariant form, providing the independence of the particle momenta. Comparison with the cor-responding result of the Dyson covariant perturbation theory is performed by es-tablishing the link between the old-fashioned perturbation theory and the cloth-ing approach.
2007-01-01
Surface morphologies of supported polyethylene (PE) catalysts are investigated by an approach combining fractal with wavelet. The multiscale edge (detail) pictures of catalyst surface are extracted by wavelet transform modulus maxima (WTMM) method. And, the distribution of edge points on the edge image at every scale is studied with fractal and multifractal method. Furthermore, the singularity intensity distribution of edge points in the PE catalyst is analyzed by multifractal spectrum based on WTMM. The results reveal that the fractal dimension values and multifractal spectrums of edge images at small scales have a good relation with the activity and surface morphology of PE catalyst. Meanwhile the catalyst exhibiting the higher activity shows the wider singular strength span of multifractal spectrum based on WTMM, as well as the more edge points with the higher singular intensity. The research on catalyst surface morphology with hybrid fractal and wavelet method exerts the superiorities of wavelet and fractal theories and offers a thought for studying solid surfaces morphologies.
Macro Photography for Reflectance Transformation Imaging: A Practical Guide to the Highlights Method
Antonino Cosentino
2014-11-01
Full Text Available Reflectance Transformation Imaging (RTI is increasingly being used for art documentation and analysis and it can be successful also for the examination of features on the order of hundreds of microns. This paper evaluates some macro scale photography methods specifically for RTI employing the Highlights method for documenting sub-millimeter details. This RTI technique consists in including one reflective sphere in the scene photographed so that the processing software can calculate for each photo the direction of the light source from its reflection on the sphere. RTI documentation can be performed also with an RTI dome, but the Highlights method is preferred because is more mobile and more affordable. This technique is demonstrated in the documentation of some prints ranging from the XV to the XX century from to the Ingels collection in Sweden. The images are here examined and discussed, showing the application of macro RTI for identifying features of prints.
Xueyong Liu
2014-01-01
Full Text Available Infrasound is a type of low frequency signal that occurs in nature and results from man-made events, typically ranging in frequency from 0.01 Hz to 20 Hz. In this paper, a classification method based on Hilbert-Huang transform (HHT and support vector machine (SVM is proposed to discriminate between three different natural events. The frequency spectrum characteristics of infrasound signals produced by different events, such as volcanoes, are unique, which lays the foundation for infrasound signal classification. First, the HHT method was used to extract the feature vectors of several kinds of infrasound events from the Hilbert marginal spectrum. Then, the feature vectors were classified by the SVM method. Finally, the present of classification and identification accuracy are given. The simulation results show that the recognition rate is above 97.7%, and that approach is effective for classifying event types for small samples.
Astigmatism error modification for absolute shape reconstruction using Fourier transform method
He, Yuhang; Li, Qiang; Gao, Bo; Liu, Ang; Xu, Kaiyuan; Wei, Xiaohong; Chai, Liqun
2014-12-01
A method is proposed to modify astigmatism errors in absolute shape reconstruction of optical plane using Fourier transform method. If a transmission and reflection flat are used in an absolute test, two translation measurements lead to obtain the absolute shapes by making use of the characteristic relationship between the differential and original shapes in spatial frequency domain. However, because the translation device cannot guarantee the test and reference flats rigidly parallel to each other after the translations, a tilt error exists in the obtained differential data, which caused power and astigmatism errors in the reconstructed shapes. In order to modify the astigmatism errors, a rotation measurement is added. Based on the rotation invariability of the form of Zernike polynomial in circular domain, the astigmatism terms are calculated by solving polynomial coefficient equations related to the rotation differential data, and subsequently the astigmatism terms including error are modified. Computer simulation proves the validity of the proposed method.
Amplitude-based detection method for gravitational wave bursts with the Hilbert-Huang Transform
Sakai, Kazuki; Kaneyama, Masato; Takahashi, Hirotaka
2016-01-01
We propose a new detection method for gravitational wave bursts. It analyzes observed data with the Hilbert-Huang transform, which is an approach of time-frequency analysis constructed with the aim of manipulating non-linear and non-stationary data. Using the simulated time-series noise data and waveforms from rotating core-collapse supernovae at 30 kpc, we performed simulation to evaluate the performance of our method and it revealed the total detection probability to be 0.94 without false alerms, which corresponds to the false alarm rate < 0.001 Hz. The detection probability depends on the characteristics of the waveform, but it was found that the parameter determining the degree of differential rotation of the collapsing star is the most important for the performance of our method.
Bhoomendra Bhongade
2014-01-01
Full Text Available A quantitative method using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS was developed and validated for the estimation of ciprofloxacin in its tablet dosage forms. The solid-state samples were prepared by dilution in dry potassium bromide and were analyzed by FTIR spectrophotometer with DRIFT sampling technique. A linear relationship for the carbonyl peak area centered around 1709 cm−1 was observed in the range of 0.3–1.5% w/w with good correlation coefficient of 0.998. The percent recovery of ciprofloxacin in three marketed tablet dosage forms was in the range of 98.76 ± 0.27. The present reported method is precise, reproducible, and eco-friendly. DRIFTS may have a potential as an alternative method for qualitative and quantitative analysis of ciprofloxacin in bulk drugs and tablet dosage forms.
REN Shou-xin; GAO Ling
2004-01-01
This paper covers a novel method named wavelet packet transform based Elman recurrent neural network(WPTERNN) for the simultaneous kinetic determination of periodate and iodate. The wavelet packet representations of signals provide a local time-frequency description, thus in the wavelet packet domain, the quality of the noise removal can be improved. The Elman recurrent network was applied to non-linear multivariate calibration. In this case, by means of optimization, the wavelet function, decomposition level and number of hidden nodes for WPTERNN method were selected as D4, 5 and 5 respectively. A program PWPTERNN was designed to perform multicomponent kinetic determination. The relative standard error of prediction(RSEP) for all the components with WPTERNN, Elman RNN and PLS were 3.23%, 11.8% and 10.9% respectively. The experimental results show that the method is better than the others.
J. E. Haugen
2012-09-01
Full Text Available The impact of climate change on water resources is usually assessed at the local scale. However, regional climate models (RCMs are known to exhibit systematic biases in precipitation. Hence, RCM simulations need to be post-processed in order to produce reliable estimates of local scale climate. Popular post-processing approaches are based on statistical transformations, which attempt to adjust the distribution of modelled data such that it closely resembles the observed climatology. However, the diversity of suggested methods renders the selection of optimal techniques difficult and therefore there is a need for clarification. In this paper, statistical transformations for post-processing RCM output are reviewed and classified into (1 distribution derived transformations, (2 parametric transformations and (3 nonparametric transformations, each differing with respect to their underlying assumptions. A real world application, using observations of 82 precipitation stations in Norway, showed that nonparametric transformations have the highest skill in systematically reducing biases in RCM precipitation.
Improved sensitivity testing of explosives using transformed Up-Down methods
Sensitivity tests provide data that help establish guidelines for the safe handling of explosives. Any sensitivity test is based on assumptions to simplify the method or reduce the number of individual sample evaluations. Two common assumptions that are not typically checked after testing are 1) explosive response follows a normal distribution as a function of the applied stimulus levels and 2) the chosen test level spacing is close to the standard deviation of the explosive response function (for Bruceton Up-Down testing for example). These assumptions and other limitations of traditional explosive sensitivity testing can be addressed using Transformed Up-Down (TUD) test methods. TUD methods have been developed extensively for psychometric testing over the past 50 years and generally use multiple tests at a given level to determine how to adjust the applied stimulus. In the context of explosive sensitivity we can use TUD methods that concentrate testing around useful probability levels. Here, these methods are explained and compared to Bruceton Up-Down testing using computer simulation. The results show that the TUD methods are more useful for many cases but that they do require more tests as a consequence. For non-normal distributions, however, the TUD methods may be the only accurate assessment method.
Mohammad Hosein Rezaei; Rahmatolah Hooshmand; Mohammad Ataei
2011-01-01
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...
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
Fukuda, Yoshiyuki; Schrod, Nikolas; Schaffer, Miroslava; Feng, Li Rebekah; Baumeister, Wolfgang; Lucic, Vladan, E-mail: vladan@biochem.mpg.de
2014-08-01
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.
A New Audio Watermarking Method Based on Discrete Cosine Transform with a Gray Image
Mohammad Ibrahim Khan
2012-09-01
Full Text Available Many effective watermarking algorithms have been proposed and implemented for digital images anddigital video. However, a few algorithms have been proposed for audio watermarking. This is due to thefact that, human auditory system (HAS is far more complex and sensitive than human visual system (HVS.In this research work, a new method of embedding image data into the audio signal and additive audiowatermarking algorithm based on Discrete Cosine Transformation (DCT domain is proposed. First, theoriginal audio is transformed into DCT domain. The DCT coefficients are divided into a fixed number ofsubsections and the energy of each subsection is calculated. Next, watermark is generated from image byimage processing algorithm. Watermarks are then embedded into selected peaks of highest energysubsection. Experimental results demonstrate that the watermark is inaudible and this algorithm is robustto common operations of digital audio signal processing, such as noise addition, re-sampling, requantization and so on. To evaluate the performance of the proposed audio watermarking method,subjective and objective quality tests including Bit Error Rate (BER and Signal to Noise ratio (SNR areconducted.
CMF Signal Processing Method Based on Feedback Corrected ANF and Hilbert Transformation
Tu Yaqing
2014-02-01
Full Text Available In this paper, we focus on CMF signal processing and aim to resolve the problems of precision sharp-decline occurrence when using adaptive notch filters (ANFs for tracking the signal frequency for a long time and phase difference calculation depending on frequency by the sliding Goertzel algorithm (SGA or the recursive DTFT algorithm with negative frequency contribution. A novel method is proposed based on feedback corrected ANF and Hilbert transformation. We design an index to evaluate whether the ANF loses the signal frequency or not, according to the correlation between the output and input signals. If the signal frequency is lost, the ANF parameters will be adjusted duly. At the same time, singular value decomposition (SVD algorithm is introduced to reduce noise. And then, phase difference between the two signals is detected through trigonometry and Hilbert transformation. With the frequency and phase difference obtained, time interval of the two signals is calculated. Accordingly, the mass flow rate is derived. Simulation and experimental results show that the proposed method always preserves a constant high precision of frequency tracking and a better performance of phase difference measurement compared with the SGA or the recursive DTFT algorithm with negative frequency contribution
Lin, Zhili; Li, Xiaoyan; Zhao, Kuixia; Chen, Xudong; Chen, Mingyu; Pu, Jixiong
2016-06-01
For an inertial confinement fusion (ICF) system, the light intensity distribution in the hohlraum is key to the initial plasma excitation and later laser-plasma interaction process. Based on the concept of coordinate transformation of spatial points and vector, we present a robust method with a detailed procedure that makes the calculation of the three dimensional (3D) light intensity distribution in hohlraum easily. The method is intuitive but powerful enough to solve the complex cases of random number of laser beams with arbitrary polarization states and incidence angles. Its application is exemplified in the Shenguang III Facility (SG-III) that verifies its effectiveness and it is useful for guiding the design of hohlraum structure parameter.
A two-step Hilbert transform method for 2D image reconstruction
Noo, Frederic; Clackdoyle, Rolf; Pack, Jed D [UCAIR, Department of Radiology, University of Utah, UT (United States)
2004-09-07
The paper describes a new accurate two-dimensional (2D) image reconstruction method consisting of two steps. In the first step, the backprojected image is formed after taking the derivative of the parallel projection data. In the second step, a Hilbert filtering is applied along certain lines in the differentiated backprojection (DBP) image. Formulae for performing the DBP step in fan-beam geometry are also presented. The advantage of this two-step Hilbert transform approach is that in certain situations, regions of interest (ROIs) can be reconstructed from truncated projection data. Simulation results are presented that illustrate very similar reconstructed image quality using the new method compared to standard filtered backprojection, and that show the capability to correctly handle truncated projections. In particular, a simulation is presented of a wide patient whose projections are truncated laterally yet for which highly accurate ROI reconstruction is obtained.
A two-step Hilbert transform method for 2D image reconstruction
The paper describes a new accurate two-dimensional (2D) image reconstruction method consisting of two steps. In the first step, the backprojected image is formed after taking the derivative of the parallel projection data. In the second step, a Hilbert filtering is applied along certain lines in the differentiated backprojection (DBP) image. Formulae for performing the DBP step in fan-beam geometry are also presented. The advantage of this two-step Hilbert transform approach is that in certain situations, regions of interest (ROIs) can be reconstructed from truncated projection data. Simulation results are presented that illustrate very similar reconstructed image quality using the new method compared to standard filtered backprojection, and that show the capability to correctly handle truncated projections. In particular, a simulation is presented of a wide patient whose projections are truncated laterally yet for which highly accurate ROI reconstruction is obtained
A two-step Hilbert transform method for 2D image reconstruction.
Noo, Frédéric; Clackdoyle, Rolf; Pack, Jed D
2004-09-01
The paper describes a new accurate two-dimensional (2D) image reconstruction method consisting of two steps. In the first step, the backprojected image is formed after taking the derivative of the parallel projection data. In the second step, a Hilbert filtering is applied along certain lines in the differentiated backprojection (DBP) image. Formulae for performing the DBP step in fanbeam geometry are also presented. The advantage of this two-step Hilbert transform approach is that in certain situations, regions of interest (ROIs) can be reconstructed from truncated projection data. Simulation results are presented that illustrate very similar reconstructed image quality using the new method compared to standard filtered backprojection, and that show the capability to correctly handle truncated projections. In particular, a simulation is presented of a wide patient whose projections are truncated laterally yet for which highly accurate ROI reconstruction is obtained. PMID:15470913
The calculation of site-dependent earthquake motions -3. The method of fast fourier transform
The method of Fast Fourier transform (FFT) is applied to the problem of the determination of site-dependent earthquake motions, which takes account of local geological effects. A program, VELAY 1, which uses the FFT method has been written and is described in this report. The assumptions of horizontally stratified, homogeneous, isotropic, linearly viscoelastic layers and a normally incident plane seismic wave are made. Several examples are given, using VELAY 1, of modified surface acceleration-time histories obtained using a selected input acceleration-time history and a representative system of soil layers. There is a discussion concerning the soil properties that need to be measured in order to use VELAY 1 (and similar programs described in previous reports) and hence generate site-dependent ground motions suitable for aseismic design of a nuclear power plant at a given site. (author)
Gao, Yingjie; Zhang, Jinhai; Yao, Zhenxing
2016-06-01
The symplectic integration method is popular in high-accuracy numerical simulations when discretizing temporal derivatives; however, it still suffers from time-dispersion error when the temporal interval is coarse, especially for long-term simulations and large-scale models. We employ the inverse time dispersion transform (ITDT) to the third-order symplectic integration method to reduce the time-dispersion error. First, we adopt the pseudospectral algorithm for the spatial discretization and the third-order symplectic integration method for the temporal discretization. Then, we apply the ITDT to eliminate time-dispersion error from the synthetic data. As a post-processing method, the ITDT can be easily cascaded in traditional numerical simulations. We implement the ITDT in one typical exiting third-order symplectic scheme and compare its performances with the performances of the conventional second-order scheme and the rapid expansion method. Theoretical analyses and numerical experiments show that the ITDT can significantly reduce the time-dispersion error, especially for long travel times. The implementation of the ITDT requires some additional computations on correcting the time-dispersion error, but it allows us to use the maximum temporal interval under stability conditions; thus, its final computational efficiency would be higher than that of the traditional symplectic integration method for long-term simulations. With the aid of the ITDT, we can obtain much more accurate simulation results but with a lower computational cost.
Sulakhudin; Abdul Syukur; Dja’far Shiddieq; Triwibowo Yuwono
2010-01-01
Effect of Coated Urea with Humic-Calcium on Transformation of Nitrogen in Coastal Sandy Soil: A Soil ColumnMethod (Sulakhudin, A Syukur, D Shiddieq and T Yuwono): In coastal sandy soil, mainly nitrogen losses due toleaching resulted to low fertilizer efficiency. Slow-release N fertilizers are proposed to minimize these losses, andhumic-calcium coated urea has been examined. A soil column method was used to compare the effects of coated ureawith humic-calcium on transformation and leaching los...
High-throughput transformation method for Yarrowia lipolytica mutant library screening.
Leplat, Christophe; Nicaud, Jean-Marc; Rossignol, Tristan
2015-09-01
As a microorganism of major biotechnological importance, the oleaginous yeast Yarrowia lipolytica is subjected to intensive genetic engineering and functional genomic analysis. Future advancements in this area, however, require a system that will generate a large collection of mutants for high-throughput screening. Here, we report a rapid and efficient method for high-throughput transformation of Y. lipolytica in 96-well plates. We developed plasmids and strains for the large-scale screening of overexpression mutant strains, using Gateway® vectors that were adapted for specific locus integration in Y. lipolytica. As an example, a collection of mutants that overexpressed the alkaline extracellular protease (AEP) was obtained in a single transformation experiment. The platform strain that we developed to receive the overexpression cassette was designed to constitutively express a fluorescent protein as a convenient growth reporter for screening in non-translucid media. An example of growth comparison in skim milk-based medium between AEP overexpression and deletion mutants is provided. PMID:26100263
A new method for RGB to CIELAB color space transformation based on Markov chain Monte Carlo
Chen, Yajun; Liu, Ding; Liang, Junli
2013-10-01
During printing quality inspection, the inspection of color error is an important content. However, the RGB color space is device-dependent, usually RGB color captured from CCD camera must be transformed into CIELAB color space, which is perceptually uniform and device-independent. To cope with the problem, a Markov chain Monte Carlo (MCMC) based algorithms for the RGB to the CIELAB color space transformation is proposed in this paper. Firstly, the modeling color targets and testing color targets is established, respectively used in modeling and performance testing process. Secondly, we derive a Bayesian model for estimation the coefficients of a polynomial, which can be used to describe the relation between RGB and CIELAB color space. Thirdly, a Markov chain is set up base on Gibbs sampling algorithm (one of the MCMC algorithm) to estimate the coefficients of polynomial. Finally, the color difference of testing color targets is computed for evaluating the performance of the proposed method. The experimental results showed that the nonlinear polynomial regression based on MCMC algorithm is effective, whose performance is similar to the least square approach and can accurately model the RGB to the CIELAB color space conversion and guarantee the color error evaluation for printing quality inspection system.
Ashcraft, C. Chace [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Niederhaus, John Henry [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Robinson, Allen C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2016-01-29
We present a verification and validation analysis of a coordinate-transformation-based numerical solution method for the two-dimensional axisymmetric magnetic diffusion equation, implemented in the finite-element simulation code ALEGRA. The transformation, suggested by Melissen and Simkin, yields an equation set perfectly suited for linear finite elements and for problems with large jumps in material conductivity near the axis. The verification analysis examines transient magnetic diffusion in a rod or wire in a very low conductivity background by first deriving an approximate analytic solution using perturbation theory. This approach for generating a reference solution is shown to be not fully satisfactory. A specialized approach for manufacturing an exact solution is then used to demonstrate second-order convergence under spatial refinement and tem- poral refinement. For this new implementation, a significant improvement relative to previously available formulations is observed. Benefits in accuracy for computed current density and Joule heating are also demonstrated. The validation analysis examines the circuit-driven explosion of a copper wire using resistive magnetohydrodynamics modeling, in comparison to experimental tests. The new implementation matches the accuracy of the existing formulation, with both formulations capturing the experimental burst time and action to within approximately 2%.
Stein's method and the zero bias transformation with application to simple random sampling
Goldstein, Larry; Reinert, Gesine
1997-01-01
Let $W$ be a random variable with mean zero and variance $\\sigma^2$. The distribution of a variate $W^*$, satisfying $EWf(W)=\\sigma ^2 Ef'(W^*)$ for smooth functions $f$, exists uniquely and defines the zero bias transformation on the distribution of $W$. The zero bias transformation shares many interesting properties with the well known size bias transformation for non-negative variables, but is applied to variables taking on both positive and negative values. The transformation can also be ...
Mottaghizadeh, Marzieh; Taghavi-Shahri, Fatemeh
2016-01-01
We analytically solved the QED $\\otimes$ QCD coupled DGLAP evolution equations at leading order (LO) quantum electrodynamics (QED) and next to leading order (NLO) quantum chromodynamics (QCD) approximations, using the Laplace transform method and then computed the proton structure function in terms of the unpolarized parton distributions functions. Our analyitical solutions for parton densities are in good agreement with those from APFEL (A PDF Evolution Library) (Computer Physics Communications 185, 1647-1668 (2014)) and CT14QED (Phys. Rev. D 93, 114015 (2016)) global parameterizations. We also compared the proton structure function, $F_{2}^{p}(x,Q^{2})$, with experimental data released by the ZEUS and H1 collaborations at HERA. There is a nice agreement between them in the range of low and high x and $Q^{2}$.
Density of states in multifragmentation obtained using the Laplace transform method
In equilibrium statistical mechanics, the density of microstates representing the statistical weight associated with a partition of an isolated system into subsystems (fragments) is the convolution of the state densities of the component subsystems. The Laplace transform approximation provides a simple representation of this density. Despite the fact that no external heat bath can be said to exist (the canonical ensemble is not appropriate) the approximation leads to partition probabilities that involve a product of factors (one for each fragment) expressed in terms of a characteristic inverse temperature. We apply the method to nuclear multifragmentation with particular emphasis on a transition that occurs when the major part of the available energy appears as kinetic (as opposed to internal excitation) energy of fragments. Finally, we discuss the shortcomings and advantages of expressing the weights of partitions with fixed total mass (charge) and multiplicity in a simple multinomial form
Fourier transform based iterative method for x-ray differential phase-contrast computed tomography
Cong, Wenxiang; Wang, Ge
2011-01-01
Biological soft tissues encountered in clinical and pre-clinical imaging mainly consist of light element atoms, and their composition is nearly uniform with little density variation. Thus, x-ray attenuation imaging suffers from low image contrast resolution. By contrast, x-ray phase shift of soft tissues is about a thousand times greater than x-ray absorption over the diagnostic energy range, thereby a significantly higher sensitivity can be achieved in terms of phase shift. In this paper, we propose a novel Fourier transform based iterative method to perform x-ray tomographic imaging of the refractive index directly from differential phase shift data. This approach offers distinct advantages in cases of incomplete and noisy data than analytic reconstruction, and especially suitable for phase-contrast interior tomography by incorporating prior knowledge in a region of interest (ROI). Biological experiments demonstrate the merits of the proposed approach.
李杰; 刘希强; 李红; 毛玉华; 郑树田
2005-01-01
Wavelet transform method is applied to measure time-frequency distribution characteristics of digital deformation data and noise. Based on the characteristics of primary modulus and stochastic white noise discrimination factor of wavelet decomposition, we analyze the variation rule of normal background and noise data from Shandong digital deformation observation data. The research results indicate that: a) 1/4 daily wave, semi-diurnal tide wave, daily wave and half lunar wave and so on quasi-periodic signal exist in the detail decomposing signal of wavelet when scale are equal to 2, 3 and 4; b) The amplitude of detail decomposing signal is the biggest when scale is equal to 3; c) The detail decomposing signal contains mainly noise corresponding to scale 1 and 5, respectively; d) We may trace the abnormal precursory which is related to earthquake by analyzing non-earthquake wavelet decomposing signal whose scale is specified from digital deformation observation data.
Instrumental phase-based method for Fourier transform spectrometer measurements processing
Phase correction is a critical procedure for most space-borne Fourier transform spectrometers (FTSs) whose accuracy (owing to often poor signal-to-noise ratio, SNR) can be jeopardized from many uncontrollable environmental conditions. This work considers the phase correction in an FTS working under significant temperature change during the measurement and affected by mechanical disturbances. The implemented method is based on the identification of an instrumental phase that is dependent on the interferometer temperature and on the extraction of a linear phase component through a least-squares approach. The use of an instrumental phase parameterized with the interferometer temperature eases the determination of the linear phase that can be extracted using only a narrow spectral region selected to be immune from disturbances. The procedure, in this way, is made robust against phase errors arising from instrumental effects, a key feature to reduce the disturbances through spectra averaging. The method was specifically developed for the Mars IR Mapper spectrometer, that was designed for operation onboard a rover on the Mars surface; the validation was performed using ground and in-flight measurements of the Fourier transform IR spectrometer planetary Fourier spectrometer, onboard the MarsExpress mission. The symmetrization has been exploited also for the spectra calibration, highlighting the issues deriving from the cases of relevant beamsplitter emission. The applicability of this procedure to other instruments is conditional to the presence in the spectra of at least one spectral region with a large SNR along with a negligible (or known) beamsplitter emission. For the PFS instrument, the processing of data with relevant beamsplitter emission has been performed exploiting the absorption carbon dioxide bands present in Martian spectra.
A stochastic Galerkin method for the Euler equations with Roe variable transformation
Pettersson, Per
2014-01-01
The Euler equations subject to uncertainty in the initial and boundary conditions are investigated via the stochastic Galerkin approach. We present a new fully intrusive method based on a variable transformation of the continuous equations. Roe variables are employed to get quadratic dependence in the flux function and a well-defined Roe average matrix that can be determined without matrix inversion.In previous formulations based on generalized polynomial chaos expansion of the physical variables, the need to introduce stochastic expansions of inverse quantities, or square roots of stochastic quantities of interest, adds to the number of possible different ways to approximate the original stochastic problem. We present a method where the square roots occur in the choice of variables, resulting in an unambiguous problem formulation.The Roe formulation saves computational cost compared to the formulation based on expansion of conservative variables. Moreover, the Roe formulation is more robust and can handle cases of supersonic flow, for which the conservative variable formulation fails to produce a bounded solution. For certain stochastic basis functions, the proposed method can be made more effective and well-conditioned. This leads to increased robustness for both choices of variables. We use a multi-wavelet basis that can be chosen to include a large number of resolution levels to handle more extreme cases (e.g. strong discontinuities) in a robust way. For smooth cases, the order of the polynomial representation can be increased for increased accuracy. © 2013 Elsevier Inc.
Study on dietary fibre by Fourier transform-infrared spectroscopy and chemometric methods.
Chylińska, Monika; Szymańska-Chargot, Monika; Kruk, Beata; Zdunek, Artur
2016-04-01
Fresh fruit is an important part of the diet of people all over the world as a significant source of water, vitamins and natural sugars. Nowadays it is also one of the main sources of dietary fibre. In fruit the dietary fibre is simply cell wall consisting essentially of polysaccharides. The aim of present study was to predict the contents of pectins, cellulose and hemicelluloses by partial least squares regression (PLS) analysis on the basis of Fourier transform-infrared (FT-IR) spectra of fruit cell wall residue. The second purpose was to analyse the composition of dietary fibre from fruit based on FT-IR spectral information in combination with chemometric methods (principle components analysis (PCA) and hierarchical cluster analysis (HCA)). Additionally the contents of polysaccharides in studied fruits were determined by analytical methods. It has been shown that the analysis of infrared spectra and the use of multivariate statistical methods can be useful for studying the composition of dietary fibre. PMID:26593472