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In this paper, a novel scheme for the secure transmission of phase images is presented. A phase image is bonded with a random amplitude mask and subjected to the Fresnel transform followed by Lorenz map. Thereafter, a random phase mask is bonded with the image obtained in previous steps. The Fresnel transform is again applied to the intermediate image resulting in an encrypted image. The decryption process is the reverse of the encryption process. The scheme is validated for a grayscale image in MATLAB environment, and a faithful recovery of input images has been recorded. The cryptosystem is exposed to statistical attacks in the form of histogram, 3-D plot, and information entropy, and results reveal that the scheme endures the statistical attacks. Simulations show that the Fresnel parameters and Lorenz map parameters are very sensitive to their original value. Results also established that the scheme is robust to noise and occlusion attacks.

The perpendicular plane ionization results of (e, 2e) triple differential cross sections (TDCS) for the Kr (4p) atoms are reported at the incident electron energies 2 eV–50 eV above ionization potential. Modified distorted wave Born approximation formalism has been employed to calculate the TDCS. The results of our calculations have been compared with the measurements of Nixon et al. and it is observed that there are certain discrepancies between theoretical and experimental results which indicate that further theoretical efforts are required to understand the cross section trends of krypton atoms in the perpendicular plane ionization.

Social Networking Sites (SNSs) provide an online platform that is used by people to build social networks or social relations with other people. Many users are not aware of the hidden threats to privacy that exist while using these SNSs. There has been a growing concern regarding these threats in general and among researchers in particular. The present study is a novel attempt to devise a measure to overcome these threatsusing fuzzy logic and IDPS(Intrusion Detection and Prevention System).This study is helpful in achieving twin objectives-(i) establishing through survey and fuzzy logic, that people are aware of the potential threats in using SNSs and (ii) helping them in securing their accounts by using the IDPS technique. Thus, it is hoped that the current study will be useful to society at large in providing more secure social networking sites.

We report on an improved maximum power point tracking (MPPT) system based on a differential power algorithm. In the proposed algorithm, which is a modified form of a perturb and observe (P&O) algorithm, differential powers, as well as voltages at different time, are compared. The proposed algorithm has been implemented with a highly efficient boost converter, in which duty cycle of a switch is varied in such a way, that the power reaches a maximum at any instant of the day, irrespective of the environmental conditions. The improved MPPT is able to reduce the number of oscillations and tracking time significantly before reaching the maximum power point (MPP). The simulated I-V and P-V characteristic curves (individual and combined) of a solar PV module were generated in MATLAB.

International audience; We report here triply differential cross sections (TDCSs) for 81 eV electron and positron-impact ionization of the combined (1b 1 + 3a 1 ) orbitals of the water molecule by using the second-order distorted wave Born approximation (DWBA2) for ejection electron and positron energies of 5 eV and 10 eV and different momentum transfer conditions. The electron-impact TDCS will be compared with the experimental data measured by Ren et al. [Phys. Rev. A 95, 022701 (2017)] and with the molecular 3-body distorted wave (M3DW) approximation results in the scattering plane as well as the perpendicular plane. The DWBA2 results are in better agreement with the experiment than the M3DW results for the scattering plane, and the M3DW results are somewhat better for the perpendicular plane. This observation is explained in terms of collision interactions. The electron and positron TDCSs are indistinguishable in the scattering plane. In the perpendicular plane, the positron results are similar in shape, but smaller in magnitude. However, the difference reduces with increasing projectile scattering angle and increasing ejected electron energy.

Electron-induced triple differential cross sections (TDCSs) have been obtained for the few outer sub-shells of tungsten atoms, namely W (6s), W (5d), W (5p) and W (4f). Tungsten and related materials have been recommended as the prime candidates for wall materials in fusion plasma devices. The electron-induced cross-section data are strongly required for the diagnostics and modeling of plasma in such devices. We observe that the trends of TDCSs obtained for the ionization of W (5d) sub-shells are very different from the TDCSs of W (6s), W (5p) and W (4f) in terms of binary and recoil peak locations as well as in the change of magnitude of TDCS with an increasing value of momentum transfer which is due to the open d-shell. The angle and energy-resolved cross-section data of tungsten atoms may be of vital importance in order to understand the spectroscopy of W atoms as wall materials as well as an impurity.

In this paper, a triple random phase encryption scheme in the Fresnel domain is presented in a 4f system. The scheme is an extension of the double random phase encoding scheme in the Fresnel domain. Firstly, the image is subjected to double random phase encoding in the Fresnel domain and thereafter, another random phase mask is bonded with it. The scheme is validated for grayscale and binary images. Cryptosystem is exposed to statistical attack in the form of histogram, 3-D plots and information entropy, and results reveal that scheme endures these statistical attacks. The sensitivity of the Fresnel parameters to their original values is also shown in the figures. A comparative analysis also performed to demonstrate that the proposed scheme is effective and provides enhanced security against known-plaintext and chosen-ciphertext attack as compared to double random phase encoding method in Fresnel domain.

In this paper, we mainly focus our attention on the global dynamical behaviour of some ubiquitous nonlinear oscillators under the presence of nonlinear dissipation. We particularly consider the parametrically driven Duffing oscillator and externally driven Helmholtz–Duffing oscillators with nonlinear dissipation term proportional to the power of velocity $$(v\left| v \right| ^{p-1})$$ . We obtain the threshold condition for the occurrence of chaos analytically as well as numerically for all the cases $$p=$$ 1, 2, 3 and 4. We also identify the regions of 2D parameter space (consisting of external forcing amplitude and damping coefficient) corresponding to various asymptotic dynamics and analyse the effect of nonlinear damping on the overall dynamical behaviour of these nonlinear oscillators.

Triple differential cross section (TDCS) results are reported for the perpendicular plane ionization of Xe (5p) at incident electron energies 5 eV, 10 eV, 20 eV, and 40 eV above ionization potential. The modified distorted wave Born approximation formalism with first as well as the second order Born terms has been used to calculate the TDCS. Effects of target polarization and post collision interaction have also been included. We compare the (e, 2e) TDCS results of our calculation with the recent available experimental data and theoretical results and discuss the process contributing to structure seen in the differential cross section. It has been observed from the present study that the second order effect and target polarization make significant contribution in description of collision dynamics of xenon at the low and intermediate energy for the perpendicular emission of electrons.

Medical imaging plays a significant role in the field of medical science. In present scenario image segmentation is used to extract abnormal tissues from normal tissues clearly in medical images. Tumor detection through brain MRI using automatic system is effective and consumes lesser time which helps doctor in diagnosis. A Tumor can convert into cancer, which is major leading cause of death. Automation of tumor detection is required for detecting tumor on early stage. Proposed work presents hybrid technique for information retrieval from brain MRI images. This research work presents an efficient technique based on K-means and artificial neural network (KMANN). GLCM (Grey Level co-occurrence matrix) used for feature extraction. Fuzzy Inference System is created using extracted feature which followed by thresholding, morphological operator and Watershed segmentation for brain tumor detection. Proposed method is used to identifying affected part of brain and size of tumor from MRI image with the help of MATLAB R2013b is used.

A During last two decades, there has been a prolific growth in the chaos based image encryption algorithms. Up to an extent these algorithms have been able to provide an alternative to exchange large media files (images and videos) over the networks in a secure way. However, there have been some issues with the implementation of chaos based image ciphers in practice. One of them is reduced/small key space due to the fact that chaotic behavior is only observed for certain range of system parameters/initial conditions of the chaotic system used in such algorithms. To overcome this difficulty, we propose a simple, efficient and robust image encryption algorithm based on combined applications of quasigroups and chaotic standard map. The proposed image cipher is based on the popular substitution-diffusion architecture (Shanon) where a quasigroup of order 256 and chaotic standard map have been used for the substitution and permutation of image pixels respectively. Due to the introduction of quasigroup as part of the secret key along with the parameter and initial conditions of the chaotic standard map, the key space has been increased significantly. The proposed image cipher is very fast due to the fact that the substitution based on the quasigroup operations is very simple and can be executed easily through the lookup table operations on Latin squares (which are Cayley operation tables of quasigroups) and the permutation is performed row-by-row as well as column-by-column using the pseudo random number sequences gener-ated through the chaotic standard map. The security and performance have been analyzed through the histograms, correlation coefficients, information entropy, key sensitivity analysis, differential analysis, key space analysis etc. and the results prove the efficiency and robustness of the proposed image cipher against the possible security threats., 33 pages, 6 Figures, 6 Tables, Accepted for publication in Journal of Applied Nonlinear Dynamics (2017)

The electron-impact ionization of inert gases for asymmetric final state energy sharing conditions has been studied in detail. However, there have been relatively few studies examining equal energy final state electrons. We report in this communication the results of triple differential cross sections (TDCSs) for electron impact ionization of Ar (3p) for equal energy sharing of the outgoing electrons. We calculate TDCS in the modified distorted wave Born approximation (DWBA) formalism including post collision interaction (PCI) and polarization potential. We compare the results of our calculation with available measurements [Phys. Rev. A 87, 022712 (2013)]. We study the effect of PCI, target polarization on the trends of TDCS for the single ionization of Ar (3p) targets.

Low energy electron impact single ionization triple differential cross section (TDCS) results are reported for the helium atoms in the threshold regime at 1 eV, 3 eV and 5 eV excess energy. TDCSs are calculated in the doubly symmetric kinematics for the coplanar to perpendicular emission of electrons. Present attempt to calculate TDCS in the second Born approximation and treating target polarization and post collision interaction is helpful to analyze the available measurements. The second order processes, target polarization and post collision interaction (PCI) have been found to be significant in describing the trends of TDCS and helpful to produce reasonably good agreement with measurements.

In this communication, the two-well Duffing oscillator with non-linear damping term proportional to the power of velocity is considered. We mainly focus our attention on how the damping exponent affects the global dynamical behaviour of the oscillator. In particular, we obtain analytically the threshold condition for the occurrence of homoclinic bifurcation using Melnikov technique and compare the results with the computational results. We also identify the major route to chaos and the regions of the 2D parameter space (consists of external forcing amplitude and damping coefficient) corresponding to the various types of asymptotic dynamics under linear (viscous or friction like) and nonlinear (drag like) damping. We also attempt to analyze how the basins of attraction patterns change with the introduction of nonlinear damping. We also present our analysis for the physically less-interesting cases where damping is proportional to the 3rd and 4th power of velocity for the sake of generalizing our findings and establishing firm conclusion.

A novel and robust chaos-based pseudorandom permutation–substitution scheme for image encryption is proposed. It is a loss-less symmetric block cipher and specifically designed for the color images but may also be used for the gray scale images. A secret key of 161-bit, comprising of the initial conditions and system parameter of the chaotic map (the standard map), number of iterations and number of rounds, is used in the algorithm. The whole encryption process is the sequential execution of a preliminary permutation and a fix number of rounds (as specified in the secret key) of substitution and main permutation of the 2D matrix obtained from the 3D image matrix. To increase the speed of encryption all three processes: preliminary permutation, substitution and main permutation are done row-by-row and column-by-column instead of pixel-by-pixel. All the permutation processes are made dependent on the input image matrix and controlled through the pseudo random number sequences (PRNS) generated from the discretization of chaotic standard map which result in both key sensitivity and plaintext sensitivity. However each substitution process is initiated with the initial vectors (different for rows and columns) generated using the secret key and chaotic standard map and then the properties of rows and column pixels of input matrix are mixed with the PRNS generated from the standard map. The security and performance analysis of the proposed image encryption has been performed using the histograms, correlation coefficients, information entropy, key sensitivity analysis, differential analysis, key space analysis, encryption/decryption rate analysis etc. Results suggest that the proposed image encryption technique is robust and secure and can be used for the secure image and video communication applications.

A recent proposal of q-deformation scheme for the nonlinear maps has stimulated new directions in the studies of various nonlinear dynamical systems. Such studies are advantageous in the analytical modeling of several nonlinear physical phenomena which cannot be perfectly represented by the standard or canonical models. This paper attempts to numerically analyze the behavior of q-deformed version of Henon map, which is one of the prototypical models exhibiting strange chaotic attractor. We particularly investigate the effect of q-deformation on the various kinds of long-term asymptotic dynamics of the canonical Henon map and also characterize the complete deformation parameter space into different regions corresponding to the periodic and strange chaotic motions. We also identify the route to chaos and new structures in the chaotic strange attractor of q-deformed Henon map.

We report the distorted wave Born approximation results of triple differential cross section of Ar (3p) by positron and electron impact. We compare the results of our calculations with the recent available experimental and theoretical results. We also provide a comparison of our positron impact ionization results with the electron impact ionization results to understand the effect of projectile charge on the projectile-target interaction.

Recently Patidar et al. [Commun Nonlinear Sci Numer Simulat 14;2009:3056–75] proposed a new substitution–diffusion image cipher using chaotic standard and logistic maps, which is very fast and possess all the confusion and diffusion properties that any good cryptosystem should have. Soon after the proposal, Rhouma et al. [Commun Nonlinear Sci Numer Simulat 2010;15:1887–92.] proposed an equivalent description of the PPS09 cryptosystem which facilitated them in the cryptanalysis of the original cipher in terms of chosen plainext and known plaintext attacks. In this paper, we propose modifications in the Patidar et al.’s image cipher to make it robust against these two cryptanalytic attacks. The security analysis shows that the modified image cipher preserves all the good properties of the original cipher and is also capable to stand against the aforesaid attacks.

Electron impact triple differential cross section (TDCS) results are reported for the single ionization of Be(2 s), Be(1 s), Be2+(1 s) and Be+(2 s) targets. The differential cross sections have been calculated in the modified distorted-wave formalism under different kinematical conditions for the coplanar emission of electrons. Due to the unavailability of experimental data, we have made a careful comparison of Be and its ions TDCS with the trends of TDCS measured for He and Li targets, which have similar electronic configurations as Be+2 and Be+ respectively. Similarity in the trends of TDCS are observed for He(1 s); Be2+(1 s) targets, Li(2 s); Be+(2 s) and Be(1 s); Be2+(1 s) targets. The effects of iso-electronic and iso-nuclear configurations on collision dynamics are observed in the trends of TDCS.

Triple differential cross sections (TDCSs) are reported for the positron and electron impact ionization of molecular nitrogen at a projectile energy of 250 eV. The TDCSs are calculated in the distorted wave Born approximation formalism using the orientation-averaged molecular orbitals. The present attempt is helpful for analyzing recent measurements (de Lucio and DuBois 2016 Phys. Rev. A 93 032710) and studying the effect of projectile charge on the ionization of a molecular target. The TDCS trends are compared for positron and electron impact ionization in terms of binary and recoil intensities and binary lobe positions for different values of energy loss. The binary emission of electrons is enhanced for positron impact; however, nearly the same recoil emission is observed for positrons as well as electron impact. Significant discrepancies are observed in the measurements in terms of the relative binary intensity for positron and electron impact.

We report the results of our modified distorted wave Born approximation calculation of triple differential cross section in the coplanar symmetric single ionization of potassium atom. We have included correlation–polarization potential as a function of electron density parameter and also studied the effect of post-collision interaction. The present attempt significantly improves the agreement between theoretical and experimental results.

Tungsten (W) and tungsten based materials have been recommended as the plasma facing component in the current fusion devices. The electron induced processes on these materials are of prime importance for the application purposes. Electron impact total ionization cross sections (TICS) are reported for the Watoms and W+ ions. The TICSs have been calculated in the variants of distorted wave approximation (DWA) using Hartree-Fock wave functions and distorted potential with semi-classical exchange. Present TICS results have been compared with the available theoretical and experimental results. Reasonable agreement with the existing theoretical results have been obtained for the TICS of W atoms by present semi-relativistic distorted wave approach, however there are certain discrepancies for the TICS of W+ ions. Differential cross sections (DCSs) have also been calculated at projectile energy 100 eV for the ionization of W atoms and W+ ions and the DCSs have been found to be sensitive on the scattering angle.

We report the results of our calculations of triple differential cross section (TDCS) for electron impact single ionization (i.e. (e, 2e) processes) from the 3s shell of argon using a modified distorted wave Born approximation formalism by including correlation–polarization potential, which accounts for both correlation and polarization effects. We observe that DWBA formalism including polarization potential is able to reproduce most of the trends of experimental data and hence provide a fututre direction for further investigation of ionization process from the 3s shell of argon. We also compare our results with the available theoretical and experimental results. The present calculations significantly improve the agreement with the experimental results but still there are certain discrepancies, which is a matter of further investigation.

Regression testing is a vast field of research. It is very costly and time consuming process but on the other hand very important process in software testing. Retest all, Test case Selection, Hybrid and Test Case Prioritization are its various techniques which are used to reduce the efforts in maintenance phase. In technical literature several techniques are present with their different and vast number of goals which can be applied in software projects despite of that they have not proven their true efficiency in the testing process. The major problem in regression testing area is to select the test case prioritization technique/s that is effective in such a way that maximum project characteristics should be cover in a minimum time span. However, consideration of this decision be carefully done so that loss of resources can be avoided in a software project. Based on the above scenario, author proposes a selection schema to support the selection of TCP techniques for a given software project aiming at maximizing the coverage of software project characteristics considering aspect of prioritization of software project characteristics. At the end, preliminary results of an experimental evaluation are presented. The purpose of this research is decision should be based on the objective knowledge of the techniques rather than considering some perception and assumptions.

We present in this communication the results of our calculation of triple differential cross section (TDCS) and spin asymmetry in TDCS in (e, 2e) processes on Li, Be+, B+2 and C+3 targets at an incident electron energy 49 eV above the ionization potential for equal as well as unequal energy sharing conditions. We have performed the calculation in distorted wave Born approximation (DWBA) formalism using static exchange potential. We also present our calculation of spin asymmetry for Li like targets as a function of energy sharing ratio and compare it with the available experimental data for Li atom. We discuss the role of exchange effect in producing spin asymmetry. We observe that the triplet scattering process plays an important role as the nuclear charge is increased. Further we observe that the spin asymmetry variation with the energy sharing ratio is also sensitive to the nuclear charge.

We present the results of our first as well as second Born calculation for the (e, 3e) process on the He atom using the three Coulomb wave approach at two incident electron energies of 1099 and 5599 eV. We demonstrate the importance of second-order projectile–target interaction in the breaking of symmetry of the fivefold differential cross section (FDCS) about the direction of momentum transfer in constant θ12 mode in coplanar geometry. Further, we note that the second Born calculation results in a shifting of the recoil peak, splitting of binary peak as well as enhancement of the recoil peak and also makes significant non-dipolar contributions to the FDCS.

In this communication we study the forced and quadratically damped Duffing oscillator system experimentally through an analogue circuit. For this purpose we design a circuit and observe its dynamical behaviour under various sets of control parameters and also compare the experimental results with the numerical simulation results.

We report triple differential cross section (TDCS) results for the perpendicular plane ionization of xenon atoms at incident electron energies 5eV, 10eV, 20eV, 30eV and 40eV above ionization potential. The TDCS calculation have been preformed within the modified distorted wave Born approximation formalism including the second order Born (SBA) amplitude. We compare the (e, 2e) TDCS result of our calculation with the very recent measurements of Nixon and Murray (Phys. Rev. A 85, 022716 (2012)) and relativistic DWBA-G results of Illarionov and Stauffer (J. Phys. B: At. Mol. Opt. Phys. 45, 225202 (2012)) and discuss the process contributing to structure seen in the differential cross section.

Triply differential cross sections for electron- and positron-induced ionization of the 3 a 1 orbital of the water molecule are calculated within the second-order distorted-wave Born approximation. In this context, distorted- wavefunctionsarenumericallycalculatedbymodelingboththeinitialandthefinalchannelswhereassingle-center Slater-type wave functions are used for describing the molecular target. A good agreement with the existing experimental data is observed. Differences in the trends of differential cross sections are observed for the electron- and positron-impact ionization.

In this paper, a novel algorithm based MPPT has been suggested for extracting maximum possible power from PV module. The proposed algorithm for controlling the MPPT is based upon the mostly used Perturb and Observe (P&O) method. Along with the proposed algorithm, different existing algorithms have been compared in terms of their tracking speed and implementation complexity. The solar module characteristics (I-V and P-V) have been simulated in MATLAB. The simulation results for various parameters of boost converter have also been obtained. In this paper, we discuss the results of our study of an improved maximum power point tracker (MPPT) of a PV system. The proposed MPPT algorithm is based on the incremental perturbation and observation (IP&O) strategy in which the perturbation steps have been increased to get closer to the maximum power point with minimum possible oscillations. The PV power system, using the proposed MPPT, will be able to optimally track maximum power points with minimum possible oscillation around maximum power points (MPPs). Consequently the light to electricity conversion efficiency can be improved significantly.

Fully differential cross sectional (FDCS) results are reported for the electron-impact double ionization of helium atoms at 5 and 27 eV excess energy. The present attempt to calculate the FDCS in the second Born approximation and treating the postcollision interaction is helpful to analyze the measurements of Ren et al (2008 Phys. Rev. Lett. 101 093201) and Durr et al (2007 Phys. Rev. Lett. 98 193201). The second-order processes and postcollision interaction have been found to be significant in describing the trends of the FDCS. More theoretical effort is required to describe the collision dynamics of electron-impact double ionization of helium atoms at near threshold.

Optimal operational & control aspects of distribution networks have been a thrust research area in academics as well as in industries since last two-three decades. In day to day practice, every one of us uses services offered by public utility distribution networks namely, water distribution network, electrical power distribution network etc. Operational topology of power distribution networks are radial in nature and hence are termed as radial distribution networks (RDN s ). Network reconfiguration has been exercised as one of the prime and widely adopted approach for operational, maintenance and control activities of an RDN. Since last two decades, researchers have been using evolutionary computation based techniques (Genetic Algorithm [1], Simulating Annealing etc) for optimal network reconfiguration. The choices of network topology for the specific purpose/application requires a careful analysis of its merits and demerits. In RDN s , the ultimate performance of a specific network topology is usually assessed by an iterative algorithm known as Load flow analysis (LFA) and its execution results in estimation of voltages, currents and losses profiles which in turn decides, whether the obtained network topology is good or bad. Thus, an obvious need is in favor of developing a conceptual frame work for faster load flow algorithm especially to meet near real-time operation requirements. In this paper, a simple and computationally efficient method for terminal (leaf) nodes identification is presented and thus, by integrating this subroutine in LFA definitely leads to an efficient and faster LFA algorithm.

A novel permutation-substitution scheme, which is based on chaotic standard map, for the image encryption is proposed. It is loss-less symmetric block cipher and specifically designed for the colour images. The initial condition & system parameter of the chaotic standard map, number of iterations and number of rounds constitute the secret key of the algorithm. Firstly we mix all three colour layers (3 D matrix) of the plain image and convert them into a 2D matrix. Each encryption round comprises of three stages: permutation rounds, substitution rounds and again permutation rounds. To increase the speed of encryption, the permutation and substitution are done row-by-row and column-by-column instead of pixel-by-pixel. The permutation process is controlled through the pseudo random number sequences (PRNS) generated from the discretization of chaotic standard map, however in the substitution, the properties of rows and column pixels of various layers are mixed with the PRNS generated from the standard map. The security of the proposed image encryption has been analyzed thoroughly using various statistical analysis, key sensitivity analysis, differential analysis, key space analysis, etc. Results suggest that the proposed image encryption technique can be used for the real time secure image and video communication applications.

Triply differential cross sections for the electron induced ionization of the 3a1 and 1b1 orbitals of the water molecule are calculated within the distorted wave Born approximation. The distorted wave functions are numerically calculated by modelling both the initial and the final channels whereas single-center Slater type wave functions are used for describing the molecular target. A good agreement with the existing experimental data is obtained.

Fully differential cross sections (FDCS) results for the electron impact ionization of water molecules taking place from 1b1, 1b2 and 2a1 orbitals are presented. The FDCS calculations have been performed in second Born approximation.

This paper focuses on a design of improved framework and analysis of existing framework which exploits certain algorithms for tracking online community in social network. Tracking of online community is an imperative task where the goal is to identify meaningful group structures in the dynamic social network and consider the problem of the evolution of groups of users in dynamic scenarios. Existing frameworks for tracking community in social network have some limitation which makes it less scalable and computationally inefficient. This novel framework facilitates scalable tracking communities over the time in social networks and offers efficient methods to deal with the problems which are offered in most of the existing frameworks.

Differential cross section results for the coplanar to perpendicular plane ionization of xenon atoms at incident electron energies of 40 and 20 eV above ionization potential are reported. The cross sections have been calculated in the modified distorted wave Born approximation (DWBA) formalism including the second-order Born amplitude. Our present attempt verifies the role of second-order processes in the ionization of xenon atoms at low and intermediate energy ranges. We compare the (e, 2e) triple differential cross section results of our calculation with the very recent measurements of Nixon and Murray (2012 Phys. Rev. A 85 022716) and relativistic DWBA-G results of Illarionov and Stauffer (2012 J. Phys. B: At. Mol. Opt. Phys. 45 225202). Overall agreement with measurements has been improved by inclusion of a second-order term in the description of the collision process.

We report the results of triple differential cross section of coplanar (e, 2e) processes on Mg (3s) atom in modified distorted wave Born approximation (DWBA). The standard DWBA formalism has been modified by including the correlation-polarization potential (which is function of electron density) and post collision interaction. We compare our computed results with the available experimental data and observe that the inclusion of polarization potential in the standard DWBA is able to improve the agreement with experimental results.

Recently, there have been several attempts to explain the features of triple differential cross section (TDCS) for the (e, 2e) processes on inert targets Ne, Ar and Xe but there are still certain discrepancies in theoretical results and measurements, which require more theoretical efforts to understand the collision dynamics of these targets. We present in this paper the results of our modified distorted wave Born approximation (DWBA) calculation of TDCS for the ionization of Ne (2p), Ar (3p) and Xe (5p) targets. We modify the standard DWBA formalism by including the correlation-polarization potential (which is function of electron density) and compare our computed results with the available experimental and theoretical data. We observe that the polarization potential is able to improve the agreement with experimental results.

Recently, several theoretical studies (Hitawala et al 2008 J. Phys. B: At. Mol. Opt. Phys. 41 035205; Khajuria and Deshmukh 2008 Phys. Rev. A 78 024702; Chauhan et al 2005 Phys. Rev. A 71 032708) have been reported to analyze the measurements of triple differential cross section (TDCS) for (e, 2e) processes on Ca (4s2) atom in coplanar geometry (Murray 2005 Phys. Rev. A 72 062711). In this paper, the (e, 2e) TDCS of the Ca atom has been revisited with the inclusion of correlation-polarization potential and post-collision interaction in the distorted wave Born approximation formalism. We note that the present attempt significantly improves the understanding of (e, 2e) processes at low energies on Ca atom. Still there are several discrepancies between the experimental and theoretical results that require more theoretical attempts to explain them properly.

This paper presents the concept of methanol decomposition using engine exhaust heat, and examines its potential for use in the operation of passenger cars, diesel trucks, and diesel-electric locomotives. Energy economy improvements of 10-20% are calculated over the representative driving cycles without a net loss in power. Some reductions in exhaust emissions are also projected.