Inversion technique

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Study on the gas performance of ceramic membrane from kaolin prepared by phase inversion technique

Study on the gas performance of ceramic membrane from kaolin prepared by phase inversion technique

In most cases, ceramic membrane fabricated through phase inversion always described and measured via it structures has been discussed before. Conversely, the membrane surface roughness also plays an important role in membrane characterizations and performances as it strongly influenced the membrane performance as well. According to Zhong et al (2013), rough surface is more easily to be fouled due to larger surface area [69]. The mechanism of fouling is always observed in liquid separation such as water separation [70], oil-water separation [69] and removal of heavy metal in wastewater [71]. As reported by Khulbe et al (1997) who studied the relationship between the surface roughness and the gas permeability of dense homogeneous membranes prepared from poly (phenylene oxide) [72]. From the study, the permeability increased while the selectivity decreased with increased membrane roughness. Furthermore, Tan and Matsuura (1999) also reported that smoother membrane roughness could enhance the selectivity of the gas mixtures [73]. As far as concerned, there are no studies of membrane roughness towards ceramic membrane via phase inversion technique for gas application. Thus, the roughness result obtained from this work will be related to the result of polymeric membrane fabricated from phase inversion system.

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A fast TDR inversion technique for the reconstruction of spatial soil moisture content

A fast TDR inversion technique for the reconstruction of spatial soil moisture content

A fast inversion technique is presented that derives capaci- tance profiles in high spatial resolution from single TDR re- flection measurements. The algorithm is based on an opti- mization approach to minimize the difference between the measurement and simulated TDR reflection data depending on a given parameter distribution. The optimization is done with conjugate gradients due to the fact that the gradient can be calculated explicitly. This gradient can be deter- mined very fast by solving only two initial-boundary-value- problems instead of several hundred when using standard Hessian matrix inversion techniques. The algorithm iterates very fast and leads to reliable soil moisture profiles which can be derived from the capacitance profiles by standard transfor- mations.

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Source parameters and site amplifications estimated by generalized inversion technique: focusing on the 2018 Hokkaido Iburi Tobu earthquake

Source parameters and site amplifications estimated by generalized inversion technique: focusing on the 2018 Hokkaido Iburi Tobu earthquake

The 2018 Hokkaido Iburi-Tobu earthquake occurred on September 6. In this earthquake, seismic intensity 7 was measured at Shikanuma, Atsuma Town, and severe damage occurred in Hokkaido. The strong motions were recorded at observation stations including those nearby the epicenter, and the seismograms at a few stations close to the epicenter showed pulse-like waveforms. In the region called Yufutsu Plain, the underground structure is quite com- plex because Yufutsu Plain is located at the western margin of the Hidaka collision zone. Thus, the mechanism of generating the observed high-amplitude ground motions in this area has not been clarified yet. We performed the generalized inversion technique to estimate the fundamental characteristics of source terms and site amplifications at Yufutsu area to investigate the mechanism mentioned above. We found that the stress drop of the mainshock of the 2018 Hokkaido Iburi-Tobu earthquake was approximately 10Mpa, which corresponds to the upper limit of the crustal earthquakes in the past, and that the short-period level A was approximately 1.17 × 10 19 N

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A Novel Image Steganography based on Secured Inversion Technique

A Novel Image Steganography based on Secured Inversion Technique

Here we applied a novel bit inversion technique to improve the stego image quality. Consider the following example to understand this technique. Four message bits 1 01 1 to be hidden into four cover image pixels 1 010 1 1 00, 1 1 1 0 1 1 0 1, 1 0 1 1 1 0 1 1 and 1 1 1 0 1 1 01. Stego-image pixels after plain LSB steganography are 1 010 1 1 0 1, 1 1 1 0 1 1 0 0, 1 0 1 1 1 0 1 1 and 1 1 1 0 1 1 0 1. Two pixels (first and second) of cover image have changed. Now, we can see that second and third LSB of three cover image pixels are 0 and 1 respectively.LSB has changed for two of these three pixels. If we invert the LSB of these three pixels, cover image pixels will be 10101100, 11101101, 10111011 and 11101100. Now, we can see that there is only one pixel of stego image which differs from cover image i.e. the last one. This results in the improvement in PSNR and hence quality of stego image is improved. For correct de steganography, we need to store the fact that we have inverted the LSBs of those pixels in which second and third LSBs are 0 and 1 respectively.

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SHALLOW WATER BATHYMETRY USING LOG-LINEAR INVERSION TECHNIQUE: A CASE STUDY AT VIZHINJAM

SHALLOW WATER BATHYMETRY USING LOG-LINEAR INVERSION TECHNIQUE: A CASE STUDY AT VIZHINJAM

The total upwelling radiance recorded by the remote sensor is a sum of the bottom radiance, atmospheric path radiance and other losses. To decode water depth information, we need to disaggregate bottom radiance from total radiance. The various image processing steps adopted to extract the bottom radiance and finally the water depth from the available imagery data using loglinear inversion technique are shown in the flow chart given in figure 3.

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Highly Adapted Polymer Templates Formed By Phase Inversion Technique for Electrodeposition of Platinum Dots

Highly Adapted Polymer Templates Formed By Phase Inversion Technique for Electrodeposition of Platinum Dots

Platinum dots were fabricated by using procedure that combines a phase separation step to form a porous polymer template followed by an electrochemical deposition step to produce Pt dots. First, the phase separation technique was used to form a thin porous polymer film of poly(vinylidene fluoride- co-hexafluoropropylene) (PVDF-HFP) on a gold substrate using a solution that contained a volatile solvent, a less volatile non-solvent and a polymer. After the polymer template was formed on the substrate, electrochemical deposition through the polymer template was performed to fill the porous film with platinum. This was followed by the removal of the template by dissolution in acetone or N- methyl-pyrrolidone (NMP) to produce Pt dots.

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Numerical solution of fractional partial differential equations by numerical Laplace inversion technique

Numerical solution of fractional partial differential equations by numerical Laplace inversion technique

In this paper, the method for numerical solution of fractional partial differential equa- tions is based on Laplace transform (LT), the homotopy perturbation method (HPM) and Stehfest’s numerical algorithm for calculating inverse Laplace transform. The accuracy and efficiency of the method is verified by solving some examples of physical interest. 2 Homotopy perturbation technique

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Tomographic Inversion Technique Using Orthogonal Basis Patterns

Tomographic Inversion Technique Using Orthogonal Basis Patterns

Tomographic reconstruction of the emission profile is a typical ill-posed inversion problem. It becomes trou- blesome in fusion plasma diagnostics because the possible location/direction of the observation is quite limited. In order to overcome the difficulty, many techniques have been developed. Among them, series expansion meth- ods are based on decomposing the emission profile with orthogonal or nearly orthogonal basis patterns. Since it is possible to ignore the surplus components with higher spatial frequency, this type of method is robust against noise issues. Two topics are discussed in this article. The first issue is the comparison of the basis systems them- selves. Conventional one of Fourier-Bessel and a new one of the so-called Laplacian eigen function are compared from the viewpoint of the capability of expressing the patterns that appear in the fusion plasma experiment. The second issue is the application to the tangential viewing imaging system. It is shown that, even from the limited information, tomographic reconstruction can be adequately performed with appropriate use of the regularization, especially with the use of the L1 regularization.

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A two-stage inversion technique for total auricular reconstruction: case report and literature review

A two-stage inversion technique for total auricular reconstruction: case report and literature review

The proposed method requires a second-stage surgery to release the buried part and reconstruct the normal shape of the auricle. The optimal tim- ing is suggested as 1 month after the previous pro- cedure, when the cartilage is fully revascularized. The technique of the second-stage surgery is adapt- able due to the actual morphology of the auricle. Besides, the cleaning and preservation of the ampu- tated segment before surgery and meticulous post- operative wound care are essential for survival. The use of antibiotics, dextran 40, and vasodilators are recommended.

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Application of Zeff Profile Analysis Based on Visible Bremsstrahlung Measurement to Different Density Profiles in the LHD

Application of Zeff Profile Analysis Based on Visible Bremsstrahlung Measurement to Different Density Profiles in the LHD

profile was analyzed with electron density and tempera- ture profiles in addition to the local bremsstrahlung emis- sivity calculation based on the Abel inversion technique with β = 1.07 %. Figure 4 shows the radial distribution of plasma parameters for a super-dense core (SDC) plasma at t 1 = 1.82 s: (a) electron density n e , (b) electron tem-

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A Novel Data Hiding Scheme for High Dynamic Range Images

A Novel Data Hiding Scheme for High Dynamic Range Images

This paper presents a novel data hiding algorithm for HDR images encoded by the OpenEXR format. The proposed algorithm conceals secret messages in the 10-bit mantissa field in each pixel, while the 1-bit sign and 5-bit exponent fields are kept intact. We recommend an optimal base allowing secret messages to be concealed with the least pixel distortion. An aggressive bit encoding and decomposition scheme is introduced herein, which offers the benefit for concealing an extra bit in a pixel group without incurring pixel distortion. The influence of the message probability is analyzed, and the embedding capacity is further increased by taking advantage of the recommended bit inversion embedding scheme. The analysis indicates that the proposed algorithm can resist attacks from the LDR and HDR RS steganalyzer and the LDR and HDR SPAM steganalysis. The contribution of this work is in presenting the first data hiding algorithm for OpenEXR HDR images. The proposed algorithm provides a high embedding capacity, which makes use of an aggressive bit encoding and decomposition scheme, as well as the bit inversion technique. Our scheme produces a stego

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FORMULATION DEVELOPMENT OF MICRO AND  NANOEMULSION OF FENUGREEK OILKhidir A. M. HassanDOWNLOAD/VIEW

FORMULATION DEVELOPMENT OF MICRO AND NANOEMULSION OF FENUGREEK OILKhidir A. M. HassanDOWNLOAD/VIEW

Formulation of a nano & microemulsion is achieved through low energy technique, using phase inversion technique and the droplet size depends on weight ratio between surfactant and oil. Different formulations of different proportions of surfactant tween 80 & fenugreek oil were prepared and added to it different amounts of water and the mixture was mixed using a vortex, for two minutes.

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Preparation and Characterization of Heterogeneous PVC-Silica Proton Exchange Membrane

Preparation and Characterization of Heterogeneous PVC-Silica Proton Exchange Membrane

Heterogeneous proton exchange membranes (PEM) are synthesized using the dry phase inversion technique. The casting solutions are prepared by dispersing a finely ground cation exchange resin particle in N,N-dimethylacetamide (DMAc) solution of polyvinyl-chloride (PVC). Results show that ion exchange capacity is increased with the addition of 1 %-wt nanosilica (from 0.14 to 0.27 meq/g) while it is decreased with a higher concentration of silica. The incorporation of 0.5%-wt nanosilica improves water uptake (from 79.2% to 94.9%) and proton conductivity (from 0.02 to 0.09 mS/cm) of PEM. However, at further silica loading those properties are decreased. The membrane with 1%-wt nanosilica and 50%-wt resin showed very good stability in the oxidative environment. The post-treatment via membrane sulfonation at the optimum condition (0.1 M of sulfuric acid and 1 h reaction time) reduces the water uptake (from 94.8% to 92.3%) but improves the IEC (from 0.27 meq/g to 0.49 meg/g) and proton conductivity (from 0.02 mS/cm to 3.07 mS/cm). Meanwhile, the post-treatment via salt solution immersion at the optimum condition (0.1 M, 24 h and 30 o C) produces less water uptake (from 94.8% to 93.1%) but improves the IEC (from 0.27 meq/g

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Preliminary fabrication of biodegradable polymer membranes from renewable resources

Preliminary fabrication of biodegradable polymer membranes from renewable resources

A membrane is an interphase between two adjacent phases acting as a selective barrier, regulating the transport substances between the two components. Microporous membranes with controlled pore size and structure were produce from biodegradable polymer based on vegetable oil monomer using phase inversion technique. The optimal conditions for the preparation of microporous polymer membranes was polymer concentrations in N,N-dimethylformamide (DMF) solution 12% (w/v), 15% (w/v), 18% (w/v) and 21% (w/v). The result, the membranes show two types of structure: pinhole- like structure and interconnected network structure. The structure of the membranes consisted of thick fibrillar elements. The membrane cross-section seemed to be composed of stacks of separate layers. Permeability of the polymer membranes obtained at lower concentrations, exhibit extremely higher water permeability with value 0.160952, 0.01482, 0.00098 and 0.00051 L/s.m 3 for 12%, 15%, 18% and 21% (w/v) respectively. As the concentration increases, the surface layer of the membranes becomes thicker. Thus, the membranes are easily break compared to the membranes that have densely packed as shown by tear test of 12%, 15%, 18%, and 21% (w/v) with 21.8495 N/mm, 13.9566 N/mm, 10.5433 N/mm, and 12.1662 N/mm tear strength respectively. The fabrication of the polymer membranes with the structure and permeability properties was successfully conducted achieved as a novel research as indicated in many work. Applications of these polymer membranes are use for water treatment, skin wound cover and, in combination with autogenous chondrocytes, as an ‘artificial periosteum’ in the treatment of cartilage defects.

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A Novel Data Hiding Scheme for High Dynamic Range Images

A Novel Data Hiding Scheme for High Dynamic Range Images

This paper presents a novel data hiding algorithm for HDR images encoded by the OpenEXR format. The proposed algorithm conceals secret messages in the 10-bit mantissa field in each pixel, while the 1-bit sign and 5-bit exponent fields are kept intact. We recommend an optimal base allowing secret messages to be concealed with the least pixel distortion. An aggressive bit encoding and decomposition scheme is introduced herein, which offers the benefit for concealing an extra bit in a pixel group without incurring pixel distortion. The influence of the message probability is analyzed, and the embedding capacity is further increased by taking advantage of the recommended bit inversion embedding scheme. The analysis indicates that the proposed algorithm can resist attacks from the LDR and HDR RS steganalyzer and the LDR and HDR SPAM steganalysis. The contribution of this work is in presenting the first data hiding algorithm for OpenEXR HDR images. The proposed algorithm provides a high embedding capacity, which makes use of an aggressive bit encoding and decomposition scheme, as well as the bit inversion technique. Our scheme produces a stego

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High Resolution in Seismic Refraction Tomography for Environmental Study

High Resolution in Seismic Refraction Tomography for Environmental Study

The synthetic model of the velocity model of the test site was carried out in this study is the result of forward modelling the seismic response of an input earth model, which in term of 2D variation in physical properties. This paper presents are modelling synthetic method which uses a gridded, inversion technique to determine the ve- locity of individual 2-dimension blocks (pixels) within a profile as opposed to modelling velocities as layers. Fig- ure 2 shows the synthetic model of the velocity model

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Inversion of Parahermitian matrices

Inversion of Parahermitian matrices

Parahermitian matrices arise in broadband multiple-input multiple- output (MIMO) systems or array processing, and require inversion in some instances. In this paper, we apply a polynomial eigenvalue decomposition obtained by the sequential best rotation algorithm to decompose a parahermitian matrix into a product of two parau- nitary, i.e. lossless and easily invertible matrices, and a diagonal polynomial matrix. The inversion of the overall parahermitian ma- trix therefore reduces to the inversion of auto-correlation sequences in this diagonal matrix. We investigate a number of different ap- proaches to obtain this inversion, and and assessment of the numer- ical stability and complexity of the inversion process.

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Inversion prediction of reservoir in Putaohua reservoir of Aobaota structure and it`s both wings

Inversion prediction of reservoir in Putaohua reservoir of Aobaota structure and it`s both wings

The inversion method commonly used has the relative wave impedance inversion (integral), recursive inversion, seismic inversion basedon model, multi parameter lithologic seismic inversion, geostatistics inversion and Markov chain Monte Carlo inversion based on. Any kind of method in the prediction of seismic inversion and reservoir has its own scope of application (table 2), In practical work should be based on the different stages of exploration and development and the specific geological problems, the combination and inversion method to select, or choose geophysical attributes effectively, interpretation and application of the reasonable.

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The Role of Inversion in the Genesis, Development and the Structure of Scientific Knowledge

The Role of Inversion in the Genesis, Development and the Structure of Scientific Knowledge

We then outline the development of number theory as a known example where inverse reasoning has played a necessary role. This is followed by suggesting a similar pattern of analysis for the structure and semantics of definitions of dimensional elements (measurable parameters)—extending the idea from the known case of number theory to the unknown cases of physical theories. These definitions, it is suggested, are to be interpreted as ‘complex predicates’ that describe ‘physical systems’. They may be viewed as semantic structures or unsaturated propositions, which are not by themselves either true or false, but will have epistemically desirable values, such as closure, invariance, and symmetry. These definitions in their own right and irrespective of their applicability, are justifiable pieces of knowledge, not only because of the values they possess but also because they developed from terra cognita. It is then shown that the two views, the generativism of scientific definitions and the simplified semantic view of scientific theories, mutually reinforce each other to form a single coherent foundation for the proposed analytico-synthetic framework. It is further argued that the various meta-theoretical predicates, such as closure, invariance, relativity and symmetry, are based on inversion, in the sense that, inversion is a necessary (though not a sufficient) condition for their emergence. Finally, it is also argued that inversion makes measurement and mathematization possible, explaining the epistemic transformation from qualitative to quantitative science. In the course of the discussion the affinities of the proposed framework with the views of H. Weyl, E. Wigner, Bas van Fraassen, F. Suppe, W. Stegm¨ uller, J. Piaget etc., among others, are presented.

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Novel Approach to Crosstalk Avoidance in RLC Modelled Interconnects Using Bus Encoder

Novel Approach to Crosstalk Avoidance in RLC Modelled Interconnects Using Bus Encoder

This research paper uses Bus- invert (BI) method for the avoidance of crosstalk delay and overall reduction in the chip- size of RLC modelled interconnects. Thus, the proposed technique transforms the bus signal to reduce and eliminates five undesirable types of crosstalk i.e. Type-0,Type-1,Type- 2,Type-3 and Type-4. They reduce power and wire

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