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Polyaniline (PANI)aMnFe2O4 nanocomposite was successfully synthesized by using 1-butyl-3-methyl-imidazolium bromide as ionic liquid and cetyl trimethylammonium bromide as surfactant via in situ polymerization. Structural, morphological, spectral and magnetic investigation of the product were done by X-ray powder diffractometry, fourier transform infrared spectroscopy, thermal gravimetric analyzer, transmission electron microscopy, vibrating sample magnetometry respectively. Electrical properties of PANIaMnFe2O4aCTAB nanocomposite was characterized with a measurement of an impedance spectroscopy, which was evaluated at frequency range varying from 1 Hz to 3 MHz for temperature range of 20a120 degree C. In general ac conductivity remained almost unchanged until it reaches up to 160 kHz, and then reduced slightly almost for all temperatures except for some slight fluctuation somehow.

The performances of a spherically bent Bragg analyzer and a cylindrically bent Laue analyzer in an X-ray Raman/emission spectrometer are compared. The reflectivity and energy resolution are evaluated from the intensity of the elastic scattering and the width of the energy distribution on a SiO 2 glass sample. Widely used, Bragg analyzers display excellent performance at the photon energy E ≤ 10 keV. However, at higher E , the reflectivity and the resolution gradually deteriorate as E increases, showing poor performance above 20 keV. On the other hand, the reflectivity of the Laue analyzer gradually increases at E  > 10 keV, displaying excellent reflectivity and good resolution around 20 keV. The Laue analyzer is suitable for X-ray absorption spectroscopy in high-energy-resolution fluorescence-detection mode or X-ray emission spectroscopy on 4 d transition metal compounds. Furthermore, the X-ray Raman features of the lithium K -edge in LiF and the oxygen K -edge feature in H 2 O, measured by nine Bragg analyzers (2 m radius) at E ≃ 9.9 keV and by five Laue analyzers (1.4 m radius) at E ≃ 19.5 keV, have been compared. Similar count rates and resolutions are observed.

This paper is designed using J2EE, HTML as a front end and Oracle 9i as a back end. SPRMAN is been developed for the client British Telecom (BT) UK., Telecom company. Actually, the requirement of BT is, they are providing Network Security Related Products to their IT customers like Virtusa, Wipro, HCL, etc. This product is framed out by set of protocols and these protocols are been associated with set of components. By grouping all these protocols and components together, product is been developed. Management of this protocol inside the product is considering as Security Protocol Review Method Analyzer. SPRMAN helps BT to overcome all the hurdles faced by them while processing the requests of their various clients using their already existing software applications. SPRMAN emphasizes on nature of the request and gives priority to issues based on their degree of future consequences. Thus, SPRMAN builds a good relationship between BT and its customers.

The Analyzers for Cusp Ions (ACIs) on the TRACERS mission measure ion velocity distribution functions in the magnetospheric cusp from two closely spaced spacecraft in low Earth orbit. The precipitating and upflowing ion measurements contribute to the overarching goal of the TRACERS mission and are key to all three science objectives of the mission. ACI is a toroidal top-hat electrostatic analyzer on a spinning platform that provides full angular coverage with instantaneous 22.5° × ∼6° angular resolution for a single energy step. ACI has an ion energy range from ∼8 eV/e to 20,000 eV/e covered in 47 logarithmic-spaced energy steps with fractional energy resolution of ∼10%. It provides reasonably high cadence (312 ms) measurements of the ion energy-pitch angle distribution with good sensitivity and energy resolution, enabling detection of cusp boundaries and characterization of cusp ion steps.

This study proposes and demonstrates a simple method for improving the energy resolution in a single‐shot X‐ray spectrometer, which consists of a focusing mirror and a single‐crystal analyzer. Two Si(220) channel‐cut crystals arranged in a non‐dispersive geometry are employed as the analyzer. The angular width of diffraction for the multi‐crystal analyzer is reduced by detuning one of the crystals, thereby enhancing the energy resolution of the spectrometer while maintaining the energy range. A proof‐of‐principle experiment with 10.4 keV X‐rays clearly shows a resolution enhancement by a factor of two. It was found that X‐ray penetration within the crystals broadened the point‐spread function on the detector, significantly impacting the energy resolution under highly detuned conditions. A long detector distance of greater than 14 m is expected to achieve a high energy resolution of 100 meV and a range of 80 eV, enabling full spectral characterization of X‐ray free‐electron laser radiation as well as advanced spectroscopy techniques. Resolution enhancement on a single‐shot X‐ray spectrometer with a detuned non‐dispersive multi‐crystal analyzer is proposed and demonstrated, indicating the promising potential for capturing the full spectral information, including the fine‐spike structure in self‐amplified spontaneous emission X‐ray free‐electron laser radiation.

This paper proposes three feature extraction (FE) methods based on density estimation for hyperspectral images (HSIs). The methods are a mixture of factor analyzers (MFA), deep MFA (DMFA), and supervised MFA (SMFA). The MFA extends the Gaussian mixture model to allow a low-dimensionality representation of the Gaussians. DMFA is a deep version of MFA and consists of a two-layer MFA, i.e, samples from the posterior distribution at the first layer are input to an MFA model at the second layer. SMFA consists of single-layer MFA and exploits labeled information to extract features of HSI effectively. Based on these three FE methods, the paper also proposes a framework that automatically extracts the most important features for classification from an HSI. The overall accuracy of a classifier is used to automatically choose the optimal number of features and hence performs dimensionality reduction (DR) before HSI classification. The performance of MFA, DMFA, and SMFA FE methods are evaluated and compared to five different types of unsupervised and supervised FE methods by using four real HSIs datasets.

The Solar Wind Ion Analyzer (SWIA) on the MAVEN mission will measure the solar wind ion flows around Mars, both in the upstream solar wind and in the magneto-sheath and tail regions inside the bow shock. The solar wind flux provides one of the key energy inputs that can drive atmospheric escape from the Martian system, as well as in part controlling the structure of the magnetosphere through which non-thermal ion escape must take place. SWIA measurements contribute to the top level MAVEN goals of characterizing the upper atmosphere and the processes that operate there, and parameterizing the escape of atmospheric gases to extrapolate the total loss to space throughout Mars’ history. To accomplish these goals, SWIA utilizes a toroidal energy analyzer with electrostatic deflectors to provide a broad 360 ∘ ×90 ∘ field of view on a 3-axis spacecraft, with a mechanical attenuator to enable a very high dynamic range. SWIA provides high cadence measurements of ion velocity distributions with high energy resolution (14.5 %) and angular resolution (3.75 ∘ ×4.5 ∘ in the sunward direction, 22.5 ∘ ×22.5 ∘ elsewhere), and a broad energy range of 5 eV to 25 keV. Onboard computation of bulk moments and energy spectra enable measurements of the basic properties of the solar wind at 0.25 Hz.

The Solar Probe ANalyzer for Ions (SPAN-I) onboard NASA’s Parker Solar Probe spacecraft is an electrostatic analyzer with time-of-flight capabilities that measures the ion composition and three-dimensional distribution function of the thermal corona and solar-wind plasma. SPAN-I measures the energy per charge of ions in the solar wind from 2 eV to 30 keV with a field of view of 247.°5 × 120° while simultaneously separating H+ from He++ to develop 3D velocity distribution functions of individual ion species. These observations, combined with reduced distribution functions measured by the Sun-pointed Solar Probe Cup, will help us further our understanding of the solar-wind acceleration and formation, the heating of the corona, and the acceleration of particles in the inner heliosphere. This paper describes the instrument hardware, including several innovative improvements over previous time-of-flight sensors, the data products generated by the experiment, and the ground calibrations of the sensor.

The MAVEN Solar Wind Electron Analyzer (SWEA) is a symmetric hemispheric electrostatic analyzer with deflectors that is designed to measure the energy and angular distributions of 3-4600-eV electrons in the Mars environment. This energy range is important for impact ionization of planetary atmospheric species, and encompasses the solar wind core and halo populations, shock-energized electrons, auroral electrons, and ionospheric primary photoelectrons. The instrument is mounted at the end of a 1.5-meter boom to provide a clear field of view that spans nearly 80 % of the sky with ∼20° resolution. With an energy resolution of 17 % ( Δ E / E ), SWEA readily distinguishes electrons of solar wind and ionospheric origin. Combined with a 2-second measurement cadence and on-board real-time pitch angle mapping, SWEA determines magnetic topology with high (∼8-km) spatial resolution, so that local measurements of the plasma and magnetic field can be placed into global context.

The MAVEN SupraThermal And Thermal Ion Compostion (STATIC) instrument is designed to measure the ion composition and distribution function of the cold Martian ionosphere, the heated suprathermal tail of this plasma in the upper ionosphere, and the pickup ions accelerated by solar wind electric fields. STATIC operates over an energy range of 0.1 eV up to 30 keV, with a base time resolution of 4 seconds. The instrument consists of a toroidal “top hat” electrostatic analyzer with a 360 ∘ × 90 ∘ field-of-view, combined with a time-of-flight (TOF) velocity analyzer with 22.5 ∘ resolution in the detection plane. The TOF combines a − 15 kV acceleration voltage with ultra-thin carbon foils to resolve H + , He + + , He + , O + , O 2 + , and CO 2 + ions. Secondary electrons from carbon foils are detected by microchannel plate detectors and binned into a variety of data products with varying energy, mass, angle, and time resolution. To prevent detector saturation when measuring cold ram ions at periapsis ( ∼ 10 1 1 eV/cm 2 s sr eV ), while maintaining adequate sensitivity to resolve tenuous pickup ions at apoapsis ( ∼ 10 3 eV/cm 2 s sr eV ), the sensor includes both mechanical and electrostatic attenuators that increase the dynamic range by a factor of 10 3 . This paper describes the instrument hardware, including several innovative improvements over previous TOF sensors, the ground calibrations of the sensor, the data products generated by the experiment, and some early measurements during cruise phase to Mars.