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Modified two-step method for stochastic differential equation's parameter estimation

Modified two-step method for stochastic differential equation's parameter estimation

Due to the difficulty and limitation in the existing classical parameter estimation methods and two-step method of SDEs with regression spline as a non- parametric estimator, a modified two-step method is introduced in this study. In the first step of modified two-step method of SDEs, we apply Nadaraya-Watson kernel regression estimator as a new non-parametric estimator to replace regression splines with truncated power series basis. Therefore, this new non-parametric estimator is expected to be very beneficial and simpler since it does not involve the computational difficulties encountered by such methods, very straight forward to use, suitable for many cases and can easily be adapted to accommodate different demand models. Thus, the modified two-step method of SDEs is considered as another option in estimating the parameters of SDEs models. The estimated parameters of one-dimensional linear SDEs models are computed using three methods such as modified two-step method, SMLE and GMM and the performances of each method will be compared in terms of percentage of accuracy and computational time
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An improved two-step method in stochastic differential equation's structural parameter estimation

An improved two-step method in stochastic differential equation's structural parameter estimation

of considering to estimate the parameters of SDE with likelihood approach, we opt to take fully non-likelihood approach by applying the two-step method used in estimating parameters of SDE with non-parametric approach. The application of non-parametric approach in SDE in previous studies includes the estimation of trends for stochastic differential equations with kernel type estimator or kernel function technique (Mishra and Rao, 2011), (Federico and Phillips, 2003), (Nicolau, 2008). Nevertheless, in Two- step method the purpose is to estimate SDE parameters with spline technique with Bayesian approach which is considered quite distinct from previous works.
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A Two-Step Method for Damage Identification and Quantification in Large Trusses via Wavelet Transform and Optimization Algorithm

A Two-Step Method for Damage Identification and Quantification in Large Trusses via Wavelet Transform and Optimization Algorithm

frequencies and mode shapes is investigated in [15] where Charged System Search (CSS) algorithm and Enhance Charged System Search (ECSS) are utilized to search for global optimum. In [16], the problem of damage detection using modal data is solved via CSS optimization algorithm and their proposed method is also validated by using three numerical examples. The problem of damage detection is solved applying frequencies and mode shapes of structures via the model updating technique using Magnetic Charged System Search (MCSS) and PSO in [17]. By utilizing natural frequencies and mode shapes to generate an Objective Function (O.F), a damage detection method based on model updating is proposed in [18] where the optimization problem is solved by continuous Ant Colony algorithm. The ABC optimization algorithm is chosen to be the optimizer to solve the damage detection problem in [19, 20] in which the authors develop an O.F by a combination of natural frequencies and modal shapes of the structure. In [21] the authors detect damages of truss structures by applying simplified Dolphin Echolocation (DE) algorithm. The O.F in the mentioned paper is formed based on natural frequencies and mode shapes of the structure. Despite the fact that model updating is regarded as one of the most effective methods of damage localization and quantification, it has one major drawback. When the number of variables considerably increases in the inverse problem, it either diverges or converges to wrong results. To tackle this problem, generally, two-step approaches are employed. To provide an illustration, it can be referred to [22] in which a two-step method is presented for damage localization and quantification in linear-shaped structures via Grey System Theory (GST) and an
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Optimization of A Two-Step Method to Synthesize Azelaic Acid from Oleic Acid

Optimization of A Two-Step Method to Synthesize Azelaic Acid from Oleic Acid

The present study deals with the oxidative cleavage of oleic acid (OA) using hydrogen peroxide and tungstic acid as a catalyst to produce azelaic acid. A two-step method has been expanded for the optimization of a new route of azelaic acid synthesis with the addition of sodium hypochlorite as the co-oxidation. The Central Composite Design (CCD) and Response Surface Methodology (RSM) were performed to optimize the production of azelaic acid. The interaction effect among catalyst concentration, substrate molar ratio and temperature were done for optimization the conversion of oleic acid. Maximum oleic acid conversion of 99.11% was reached at substrate molar ratio of 4/1 (H 2 O 2 /OA), a catalyst concentration of 1.5% (w/wOA) and temperature of 70 o C. The GC analysis
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A Two-Step Method for the Low-Sidelobe Synthesis of Uniform Amplitude Planar Sparse Arrays

A Two-Step Method for the Low-Sidelobe Synthesis of Uniform Amplitude Planar Sparse Arrays

Abstract—A two-step method combining the algorithms of iterative Fourier transform (IFT) and differential evolution (DE), called IFT-DE, is proposed in this paper for the low sidelobe synthesis of a uniform amplitude planar sparse array (PSA). Firstly, the entire aperture of the array is divided into a set of square lattices that are spaced at half wavelength. Then the elements are forced to be located on the lattices through performing IFT, so that a planar thinned array (PTA) is formed across the aperture. Undoubtedly the interval between adjacent elements of the PTA is an integer multiple of half wavelength. In the second step, for each column of PTA the elements spaced greater than or equal to a wavelength are selected as the candidates whose locations need to be optimized by DE procedure, as long as the renewed inter-element spacing is not less than half wavelength. Consequently, a PSA with reduced sidelobe level may be obtained. According to the aforementioned selection rule, only a small part of elements that account for the total number need to be relocated, which denotes that the number of individual parameters waiting for optimizing by DE is decreased considerably, and thereby greatly accelerates the convergence speed of the algorithm. A set of synthesis experiments for PSA ranging from small to moderate size are presented to validate the effectiveness of the proposed method.
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Hygienic Property of Microfiber Synthetic Leather Base Modified via a "Two-Step Method"

Hygienic Property of Microfiber Synthetic Leather Base Modified via a "Two-Step Method"

cross-linked to the base via the "two-step method." The water absorption ability of the base also significantly increased. The thermal weight loss of the three kinds of base were compared and analyzed to further confirm the experimental results. As shown in Figure 4, the base began to gradually disappear at 230 ℃. The treatment with formic acid had no effect on the thermal weight loss of the base; however, the thermal weight loss rate of the modified base via the "two-step method" relatively increased, because when the thermal weight loss was 5 wt%, the temperature of unmodified base, NH 2 -HBP, and gelatin hydrolysate was about
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Two-Step Method Useful For Support of Technical Benchmarking Practice in the Automotive Market

Two-Step Method Useful For Support of Technical Benchmarking Practice in the Automotive Market

Table 3 illustrates some details relative to 35 car models identified by DEA as 100 % efficient. As the previous table showed, this group of cars is rather variegated as it contains models that belong to several market segments classified, for instance, as A (i.e., Fiat 127), B (Simca 1000 Rallye), or even sport cars (Lamborghini Diablo VT). That should not be surprising, as DEA identifies efficient units on the base of the ratio of weighted outputs to weighted inputs. The last column but one presents information that is useful to assess the competitiveness of cars, i.e. the number of times each model compares in the reference set of an inefficient car. Seven passenger cars – Mazda RX2 Coupè, Talbot Sunbeam Lotus, Jaguar XJ5.3, Saab 900 Saero, Ford SuperEscort RS luxury, Mercedes 280E-24V, and Lamborghini Diablo VT – have only themselves as a reference car, not being in any reference set. This information can be used to identify market niches of the product offering. “A niche market is a relatively small segment of a market that the major competitors or producers may overlook, ignore, or have difficulty serving. The niche may be a narrowly defined geographical area, it may relate to the unique needs of a small and specific group of customers, or it may be some narrow, highly specialized aspect of a very broad group of customers” (Gross et al., 1993, p. 360). Effective niche strategies may be sometimes very profitable, because a niche market may actually be very large. Emphasis on niche marketing provides a very clear focus for the development of business strategies and action plans. As a final comment about figures in the “occurrence in reference sets” column, two car models merit particular attention, Daihatsu Charade Gti Turbo and Subaru M80 5P, the first one in the reference sets of 145 cars and the second in those of 94 cars. So, even though both cars are efficient, they occupy a market position that clearly is not defendable. Unexpectedly, the Ferrari 512 TR that was sold in the market in the 1990s appears in the reference sets of 12 cars, including some cars that do not belong to the same market segments (e.g., BMW 318i and BMW 730i). Of course, customers who buy a Ferrari car do not expect to have higher technical value as the only benefit for their expensive purchase!
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Rhombohedral-structured LiVO2 Prepared by a Novel Two- Step Method and Its Electrochemical Properties

Rhombohedral-structured LiVO2 Prepared by a Novel Two- Step Method and Its Electrochemical Properties

ions from the transition metal layers to the lithium layer during the initial charging process [11]. The structural change prevents lithium ions from being back to their original sites, resulting in poor reversibility.But the reversible capacity of sample about 130 mAh g -1 incline to stabilized and almost no decay after 30 cycles, illustrating the LiVO 2 which synthesized by a two-step reduction method has

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A Simplified and Reproducible Two-Step Method for the Purification of Prostate-Specific Antigen

A Simplified and Reproducible Two-Step Method for the Purification of Prostate-Specific Antigen

Our results reflect the molecular charge and size relationship between the PSA and the other proteins in human semen. The most acidic isoform of PSA has an isoelectric point of 6.8, while most of the other seminal proteins are more acidic. Therefore, in our first step of purification, all isoforms of PSA bind to CMSephadex, whereas most of the other proteins were eluted in the void volume. With regard to size, human seminal plasma PSA is the major protein in the 20,000 to 40,000 molecular weight range as shown by SDS- PAGE analysis (Figure 3). Therefore, when the fractions containing PSA were further fractionated using the high resolution matrix Sephacryl S-200, a major symmetrical protein peak corresponding to PSA was obtained.
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Implementation of MALDI-TOF Mass Spectrometry and Peak Analysis: application to the discrimination of Cryptococcus species and their interspecies hybrids

Implementation of MALDI-TOF Mass Spectrometry and Peak Analysis: application to the discrimination of Cryptococcus species and their interspecies hybrids

To improve the identification of the interspecies hybrids and their discrimination from C. deneoformans and C. neoformans, peak analysis was performed. The search for species-specific biomarker peaks yielded a list of 10 peaks that allowed the differentiation of the Cryptococcus species analysed, with 5 of them showing higher discriminative power (Table 2). The two-step method allowed correct differentiation of the interspecies hybrids which clustered distinctly in the dendrograms built using two different hierarchical clustering variations (Figure 2 and Figure S2). These dendrograms showed three different clusters where C. deneoformans isolates were clearly separated from C. neoformans and the interspecies hybrids. Accurate differentiation among the 3 Cryptococcus species was achieved using the peak matrix built upon the 5 most discriminative peaks, with only one spectrum from an interspecies hybrid misallocated in the C. neoformans cluster (Figure 2B). C. neoformans and the interspecies hybrids showed close relatedness between them based on their protein spectra.
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Two step Runge Kutta Nyström method for solving second order ordinary differential equations

Two step Runge Kutta Nyström method for solving second order ordinary differential equations

Chapter 4 will discuss the development of order conditions from order one up to order four for TSRKN method by using Taylor series expansion. A two-stage third-order and three-stage fourth-order explicit TSRKN method were derived using the same strategy as found in Chapter 3. Several problems are solved and their numerical results are compared with the existing RK method of the same order. For existing RK method of order three, comparisons are made with methods derived by Butcher (1987) and van der Houwen and Sommeijer (1987). Likewise, comparisons are made with RK method of order four derived by Lambert (1991) and RKN method of order four derived by van der Houwen and Sommeijer (1987). Stability interval for all methods will also be presented.
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Combined Method of Two Stage LPG PCA Denoising with Impact on Preprocessing Step for Noisy Images

Combined Method of Two Stage LPG PCA Denoising with Impact on Preprocessing Step for Noisy Images

Image smoothing is a technique of improving the quality of an image by removing the noise in that image [7]. Among the several image processing technique we introduce LPG-PCA De-noising with preprocessing step to improve the quality of an image compare to existing methods. PCA is a de- correlation technique in statistical signal processing which can be used in several applications like pattern recognition, Dimensionality reduction, etc. In PCA the local statistics are calculated from the local PCA transformation matrix by using the moving window. In LPG-PCA the local statistics are computed in such a way that it preserves the edge structures of the image after the shrinkage in the PCA domain [1]. The diffusion process can be seen as an evolution process with an artificial time variable t denoting the diffusion time where the input image is smoothed at a constant rate in all directions [6]. Linear Diffusion is a conventional way to smooth an image in a controlled way to convolve with a Gaussian kernel. The main drawback of linear diffusion method is, the smoothing process does not consider the information about important image features such as edges. It follows that same amount of smoothing to be applied at every image location. As a result,
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Two Step

Two Step

It was that afternoon that he learned that she had grown up a dancer—that she was in ballet performances by the time she was four, that she had gone to dance school for ten years in a city two states from her home, and that she had spent a year between high school and college touring the world as part of a premier ballet troupe. He remembered being impressed, intimidated, proud—then surprised and almost relieved to hear that four years at a state university was her escape from the rigors of competitive dance, that her career in photography was her opportunity for anonymity, for turning the spotlight from herself and onto others, for taking the time to catch for posterity a series of perfect moments that could be neither directed, performed, nor lost. Dance, she said, was a depressing profession for her—she felt she was showing people a kind of beauty found only on stages in opera houses. But photography, she said, is an avenue of hope she can use to reveal sweet snatches of the beauty found in the motion of everyday life. She’d told him that after she graduated she never planned to dance again.
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Reducing Papr and Channel Equalisation in OFDM

Reducing Papr and Channel Equalisation in OFDM

Several techniques are available for reducing PAPR they are Interleaved OFDM, Tone Injection(TI), Tone Reservation(TR), Selective Mapping(SLM), Partial Transmit Sequence(PTS, active constellation extension (ACE)) and Signal Distortion techniques. Signal Distortion techniques are Companding, Peak Windowing, Clipping and Filtering and Peak Cancellation. The companding destroys the orthogonality of OFDM subcarriers and the signals cannot recoverable at the receiver. Clipping is one of the simplest method for application and it did not require any receiver side processing, but it distorts the signal and decreases the BER of the system. TI, TR, and ACE do not distort the signal, but these methods cause energy increases of the transmitted signal. SLM neither cause any distortion in the signal nor causes any energy increases in the signal. But its application is more complex than the others methods. ICF is attractive because it is simple to implement and it does not require a predefined clipping ratio.
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Final Edit Thesis.pdf

Final Edit Thesis.pdf

Podoviridae. The next category of bacteriophages, those that are polyhedral, are comprised of the families Microviridae, Corticoviridae, Tectiviridae, Leviviridae and Cystoviridae. These families are grouped based on whether they possess DNA or RNA. Microviridae, for instance, are small, have no envelope and contain a single piece of circular single-stranded DNA (Ackermann, 2003). Cystoviridae, on the other hand, contain three molecules of double-stranded RNA and RNA polymerase. Their capsids are also surrounded by lipid-containing envelopes, which they lose after entering the space between a cell’s cell wall and cytoplasmic membrane. The Inoviridae family of bacteriophages, which are comprised of Lipothrixviridae and Rudiviridae, start out single-stranded, however after infection within the cell, convert to double-stranded DNA. This group of viruses occur in enterobacteria and are sensitive to chloroform and sonication, yet resistant to heat (Ackermann, 2003). A final category of bacteriophages, the pleomorphic phages, are made up of the groups Plasmaviridae and Fuselloviridae. Plasmaviridae particles have no capsid and consist of an envelope and a “dense nucleoprotein granule.” These viruses infect their hosts by fusing their viral envelope with the mycoplasma cell membrane, releasing their viral particles by budding. Fuselloviridae, on the other hand, are lemon-shaped particles consisting of two hydrophobic proteins and host lipids, with short spikes at one end
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Some new two step iterative methods for solving nonlinear equations using Steffensen’s method

Some new two step iterative methods for solving nonlinear equations using Steffensen’s method

Inspired and motivated by the ongoing research activities in this area, we suggest and ana- lyze a new iterative method for solving nonlinear equations. To derive these iterative methods, we show that the nonlinear function can be approximated by a new series which can be obtained by using the trapezoidal rule for approximating the integral in conjunction with the fundamen- tal theorem. This new expansion is used to suggest these new iterative methods for solving nonlinear equations. We also consider the convergence analysis of these methods [15].

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Study the Dynamics and Variability of River Indus Flow

Study the Dynamics and Variability of River Indus Flow

This paper provides the realistic approaches about the dynamics and variability of Indus River that helped to take possible action to reduce the damages of the flood environmental management, a wide scope covering various interlinked policies. Moreover, it also reviews the role played by different factors in the dynamics and variability of Indus River flow and will contribute in understandings of their future projections. Regression analysis and trend detection of a phenomena based on climate has involved the attention of masses for a long period of time. This paper will discuss in detail the simple methods of trend detection using the techniques of least square estimation and Mann-Kendall test and also incorporates multiple linear regression technique. Trend analysis is an important tool used for determining the behaviour (generally increasing or decreasing) of statistical variations of a random variable. It can be demarcated as the procedure to enumerate and elucidate the changes in any stochastic system for the given epoch of time scale. Regression is a mathematical modelling method, used to explain the interrelations of the phenomena. The two step regression method (step-wise and general regression) have been utilised in this paper. Twenty seven years of mean monthly data of the seven stations of Indus River flow have been used to explore their connection with the, mean monthly temperature of the three cities and the four cities of sum of monthly precipitation. The results of this paper may help to understand the physical phenomena based on the statistical variation with respect to time and space in the river flow. Moreover, It will be useful for agriculture, hydropower generation and water management sectors in planning the future scenarios. 2 Data and Methodology
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A Two-Step Synthesis of 2-Spiropiperidines

A Two-Step Synthesis of 2-Spiropiperidines

However, we were unable to extend this reaction to the synthesis of 2-spiropiperidines, as the N-tosyl group was either eliminated in the Mannich-like step or it inhibited the cyclisation step when ketones were used. These problems were overcome by the use of N-Boc imines and the Weiler dianion [19] (Scheme

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Securing Information: Cryptography and Steganography

Securing Information: Cryptography and Steganography

Abstract:Today’s dynamic and information rich environment, information systems have become vital for any organization to survive. With the increase in the dependence of the organization on the information system, there exists an opportunity for the competitive organizations and disruptive forces to gain access to other organizations information system. This hostile environment makes information systems security issues critical to an organization. Current information security literature either focuses on anecdotal information by describing the information security attacks taking place in the world or it comprises of the technical literature describing the types of security threats and the possible security systems. Two of the best ways to provide security is Cryptography and Steganography. Cryptography and Steganography are cousins in the spy craft family. Cryptography scrambles a message so it cannot be understood and generates cipher text. Steganography word is derived from Greek, literally means “Covered Writing”. Steganography is the art of hiding the existence of data in another transmission medium to achieve secret communication. It does not replace cryptography but rather boosts the security using its obscurity features. It includes vast ways of secret communications methods that conceal the message’s existence. These methods are including invisible inks, microdots, character arrangement and covert channels & spread spectrum communications.
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Two-Step Machine Translation with Lattices

Two-Step Machine Translation with Lattices

We follow Bojar et al. (2012) formulation to represent the middle language: using LOF+MOT (single token) or LOF | MOT (multi-factor token). The first representation is simply created by concatenating the LOF and the MOT, ap- plying a single language model to them, whereas in the later representation two separate LMs are used one for each fac- tor. We keep the translation model practically identical in both variants: we use just one translation step, always pro- ducing both LOF and MOT at once. This approach ob- viously lacks some generalization but it keeps the search space simple.
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