Image spam analysis and detection

Image spam is unsolicited bulk email, where the message is embedded in an image. Spammers use such images to evade text-based filters. In this research, we analyze and compare two methods for detecting spam images. First, we consider principal component analysis (PCA), where we determine eigenvectors corresponding to a set of spam images and compute scores by projecting images onto the resulting eigenspace. The second approach focuses on the extraction of a broad set of image features and selection of an optimal subset using support vector machines (SVM). Both of these detection strategies provide high accuracy with low computational complexity. Further, we develop a new spam image dataset that cannot be detected using our PCA or SVM approach. This new dataset should prove valuable for improving image spam detection capabilities.     

Microbial conversion of sulfur dioxide in flue gas to sulfide using bulk drug industry wastewater as an organic source by mixed cultures of sulfate reducing bacteria

Mixed cultures of sulfate reducing bacteria (SRB) were isolated from anaerobic cultures and enriched with SRB media. Studies on batch and continuous reactors for the removal of SO(2) with bulk drug industry wastewater as an organic source using isolated mixed cultures of SRB revealed that isolation and enrichment methodology adopted in the present study were apt to suppress the undesirable growth of anaerobic bacteria other than SRB. Studies on anaerobic reactors showed that process was sustainable at COD/S ratio of 2.2 and above with optimum sulfur loading rate (SLR) of 5.46kgS/(m(3)day), organic loading rate (OLR) of 12.63kg COD/(m(3)day) and at hydraulic residence time (HRT) of 8h. Free sulfide (FS) concentration in the range of 300-390mgFS/l was found to be inhibitory to mixed cultures of SRB used in the present studies.     

Preparation and characterization of quercetin and rutin cyclodextrin inclusion complexes

The objective of the present study is to prepare and characterize cyclodextrin inclusion complexes of quercetin and rutin to improve their aqueous solubility and dissolution properties. Inclusion complexes of quercetin and rutin with beta-cyclodextrin (beta-CD) and hydroxyl propyl-beta-cyclodextrin (HP-beta-CD) were prepared by kneading and coevaporation methods. Characterization of inclusion complexes was done by phase solubility analysis and was supported by X-ray powder diffractometry (XRD), differential scanning calorimetry (DSC), and Fourier-transform infra red spectroscopy (FT-IR) analysis. Inclusion complexes exhibited higher rates of dissolution than the corresponding physical mixtures and pure drug. Higher dissolution rates were observed with HP-beta-CD kneaded complexes in comparison to the products with beta-CD.     

Power law-based local search in spider monkey optimisation for lower order system modelling

The nature-inspired algorithms (NIAs) have shown efficiency to solve many complex real-world optimisation problems. The efficiency of NIAs is measured by their ability to find adequate results within a reasonable amount of time, rather than an ability to guarantee the optimal solution. This paper presents a solution for lower order system modelling using spider monkey optimisation (SMO) algorithm to obtain a better approximation for lower order systems and reflects almost original higher order system's characteristics. Further, a local search strategy, namely, power law-based local search is incorporated with SMO. The proposed strategy is named as power law-based local search in SMO (PLSMO). The efficiency, accuracy and reliability of the proposed algorithm is tested over 20 well-known benchmark functions. Then, the PLSMO algorithm is applied to solve the lower order system modelling problem.     

Effect of Nd~(3+) on spectroscopic properties of lithium borate glasses

The spectroscopic properties of lithium borate glasses as a function of Nd3＋ ions concentration were reported.Optical absorption spectra of these glasses showed a number of absorption bands in ultra violet and visible region.Optical absorption edge was found to shift towards the longer wavelength（red shift） with increase in Nd2O3.Luminescence spectra revealed three major bands at 902, 1063 and 1334 nm which was due to 4F3/2→4I9/2, 11/2 ＆13/2 transitions of Nd3＋ ions.Luminescence intensity was maximum for 1 mol.% Nd2O3 and further increase in Nd2O3 resulted in luminescence quenching.The luminescence quenching behavior at higher concentration of Nd2O3 was attributed to the Nd3＋-Nd3＋ interaction in the glass matrix.An absorption and emission property of these glasses suggested that these glasses could be useful for 1.06 μm infrared laser applications.     

Fluorescence properties of Ho3 doped fluorophosphate glasses

This paper reports the formation of a new series of Ho³⁺ -doped fluorophosphate optical glasses in the chemical formulae: 50 (NaPO₃)₆ + 18 BaF₂ + 10 ZnF₂ + 20 RF + 2 HoF₃ where RF = LiF, NaF, KF, (LiF-NaF), (NaF-KF) and (KF-LiF). The physical properties, absorption and photoluminescene spectra have been measured to understand the optical behaviours of these Ho³⁺ -glasses as a function of the alkali content changes in the host glass matrices.     

Absorption and emission spectral analysis of Pr<Superscript>3+</Superscript>: tellurite glasses

This paper reports on the results concerning optical absorption and fluorescence properties of 60TeO₂–25ZnO–10BaO–4.5La₂O₃–0.5Pr₂O₃ (Pr³⁺: TZBL) glass. Both electronic (α_e) and vibrational (α_v) band edge cut-off wavelengths of the host glass (TZBL) have been evaluated from the measurement of its UV–Vis and IR transmission spectra. The glass studied has shown 80% transmittance throughout its optical window from 0.366 μm (α_e = 3.39 eV) to 6.30 μm (α_v = 0.197 eV). The FT-IR transmission spectra of Pr³⁺ doped and also reference tellurite glasses have demonstrated the presence of TeO₄ and TeO₃₊₁ or TeO₃ structural units. The thermal properties of this glass have been investigated from the study of DTA profile. The recorded optical absorption spectra of Pr³⁺: TZBL glass have shown eight absorption bands from 300 nm to 2,500 nm. The fluorescence emission has been observed mainly from ³P₁, ³P₀ and ¹D₂ states to the lower lying states and which are assigned to the transitions of ³P₀→ ³H_4,5,6; ³P₀→ ³F_2,3,4; ³P₁→³H₅ & ¹D₂→³H_4,5 upon excitations at three excitation states of ³P_0,1,2. From the time resolved spectra, it is found that ³P₀ level decays faster than ¹D₂ level. The fluorescence decay kinetics of ³P₀ and ¹D₂ levels have been measured and the lifetimes are found to be 21 and 39 μs, respectively.     

Processing and Properties of Eu3+:LiTaO3 TransparentGlass–Ceramic Nanocomposites

We report here the processing and properties of transparent glass and glass–ceramic nanocomposites in the Li₂O–Ta₂O₅–SiO₂–Al₂O₃ system in the presence of Eu₂O₃ as luminescent probe. The formation of the LiTaO₃ crystal phase, the crystallite size, and the morphology with the progression of heat treatment have been examined by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transformed infrared reflectance spectroscopy measurements. The crystallite sizes obtained from XRD and TEM are found to increase with heat-treatment time and vary in the range of 2–20 nm. The measured photoluminescence spectra exhibit emission transitions of ⁵D_0,1→⁷F _j ( j =0, 1, 2, 3, and 4) of Eu³⁺ ions. From the nature of the emission transitions, the site symmetry in the vicinity of Eu³⁺ ions has been found to be near C_3v in the glass–ceramic nanocomposites. An inverse correlation has been observed between the asymmetric ratio ( I _ED/ I _MD) of Eu³⁺ ions and the dielectric constant (ɛ_r), with an increase in the heat-treatment time of glass, which is caused by the dipole–dipole interaction.     

Influence of processing on the extension of shelf-life of Nagli-fish (Sillago sihama) by gamma radiation

Studies were carried out to evaluate the microbiological profile, shelf-life and quality of Nagli fish (Sillago sihama) subjected to gamma irradiation. Non-irradiated samples were unacceptable organoleptically after 7–8 days of storage at 1–2°C while irradiated samples (2 and 3 kGy) were acceptable up to 19 days. Dressing prior to irradiation had no additional advantage to shelf-life over whole fish. Total bacterial count (TBC), total volatile basic nitrogen (TVBN), trimethylamine (TMA) and sensory evaluation data revealed no significant differences between whole and dressed fish. Salmonella sp. were not detected in 3 kGy-irradiated samples whereas 2 kGy destroyed Vibrio parahaemolyticus and Staphylococcus aureus. Listeria monocytogenes and Yersinia enterocolitica were not detected but non-pathogenic species such as L. grayi, L. murrayi, and Y. tuberculosis were present in the fish prior to irradiation. Irradiation doses of 2 and 3 kGy destroyed Yersinia sp. and Listeria sp., respectively. These organisms were not detected during storage of the treated fish.