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The tooth fracture failure modes in the spur gear tooth root are mainly influenced by the magnitude and positions of bending fatigue load along the gear face width. Numerous studies in the literature used 3D finite element (FE) models to analyze crack propagation, but they did not take into account the effect of the load distribution ratio (LDR) throughout the gear face width, either in a moving load model or a uniform load model. In this study, an effort is made to investigate the impact of LDR and Load Sharing Ratio (LSR) in the modeling of moving loads for various loading positions and measure the actual crack propagation behavior of a spur gear with a root fracture using the 3D FE technique. Further, the influences of FE spur gear models on the variation of Actual Load Distribution with the effect of LSR, Stress Intensity Factors (SIFs), and crack propagation paths are also studied. A 3D FE crack propagation modeling procedure is validated with the experimental results of the SAEJ1619 fatigue test procedure. The experimental investigation using standard SAEJ1619 fatigue test procedure shows that the symmetric crack propagation failure at the crack front of the spur gear tooth was observed for a given uniform bending fatigue load. The results show that the mode I SIFs (KI) and mode II SIFs (KII) are dominant at the crack opening displacement for the positions of moving load between the Highest Point of Single Tooth Contact (HPSTC) and Highest Point of Tooth Contact (HPTC) lines. But, the KII is highly influenced by KI for further crack growth when the load is moved to the HPSTC line than the HPTC line. This study provides the guidelines to predict the actual crack propagation path failure behavior for various positions of moving load for various gear drive systems with root crack. [ABSTRACT FROM AUTHOR]

The effect of higher molecular weight bismuth oxide incorporation in influencing the properties of ternary zinc barium tellurite glasses with maximum limit of 10 mol.% is explored and reported. A systematic increase in the density values and glass transition temperature were observed with gradual incorporation of Bi2O3, which influences and increases cross-linking in the glass network. Raman spectral studies confirmed the structural modification from 6 mol.% of bismuth with 740 cm−1 peak dominating compared to that of 660 cm−1. Formation of non-bridging oxygen replacing bridging oxygen atoms could be validated from Raman and energy bandgap measurements. The presence of all the elements and their corresponding oxidation states were confirmed from XPS measurements. Standard Phy-X/PSD software was used to validate the influence of bismuth oxide in improving the radiation shielding properties of zinc barium tellurite glasses. Calculated results showed a continuous increase in attenuation coefficients with bismuth doping, wherein 10 mol.% sample had the highest value. Lower half value layer and mean free path values of 3.17 and 3.88 cm respectively at a particular photon energy value for 10 mol% bismuth oxide indicated theoretically the significance of doping bismuth oxide in improving the shielding properties of zinc barium tellurite glasses. The obtained values can be used as a basis to experimentally validate the utility of these glasses in shielding applications. [ABSTRACT FROM AUTHOR]

In light of the unprecedented growth in internet usage, safeguarding data from unauthorized access has emerged as a paramount concern. Cryptography and steganography stand as pivotal methods for ensuring data security during transmission. This study introduces an innovative adaptive video steganography approach featuring three tiers of security for extracting concealed information, thereby facilitating secure communication. The embedding process operates within the spatial domain of cover video frames, enabling a remarkable hiding ratio of up to 28.125% (equivalent to 2.25 bits per pixel in payload) without compromising the quality of video frames. Users are afforded the flexibility to select between partial or full embedding capacity of CVF through the proposed adaptive control block (ACB). The chaotic key generator (CKG), which combines a logistic map and sine map, is employed to generate highly sensitive initial seeds for permutation order (PO), frame selection (FS), and random position for hiding (RPH), thereby ensuring three levels of security. Prior to transmission, both CVF and hidden data (SD) are encrypted using PO. Encrypted CVFs are then randomly selected using FS for embedding, with RPH employed during the embedding process. Subsequently, for transmitting the stego-video frame, embedded CVFs are decrypted using the same PO. Experimental results demonstrate the efficacy of the proposed approach, achieving an adaptive hiding ratio ranging from 7.1 to 28.125% (equivalent to 0.56 to 2.25 bits per pixel in payload) and maintaining a peak signal-to-noise ratio (PSNR) within the range of 50.25 to 62.05 dB. [ABSTRACT FROM AUTHOR]

Smart cities and the Internet of Things have enabled the integration of communicating devices for efficient decision-making. Notably, traffic congestion is one major problem faced by daily commuters in urban cities. In developed countries, specialized sensors are deployed to gather traffic information to predict traffic patterns. Any traffic updates are shared with the commuters via the Internet. Such solutions become impracticable when physical infrastructure and Internet connectivity are either non-existent or very limited. In case of developing countries, no roadside units are available and Internet connectivity is still an issue in remote areas. Internet traffic analysis is a thriving field of study due to the myriad ways in which it may be put to practical use. In the intelligent Internet-of-Vehicles (IOVs), traffic congestion can be predicted and identified using cutting-edge technologies. Using tree-based decision-tree, random-forest, extra-tree, and XGBoost machine learning (ML) strategies, this research proposes an intelligent-transport-system for the IOVs-based vehicular network traffic in a smart city set-up. The suggested system uses ensemble learning and averages the selection of crucial features to give high detection accuracy at minimal computational costs, as demonstrated by the simulation results. For IOV-based vehicular network traffic, the tree-based ML approaches with feature-selection (FS) outperformed those without FS. When contrasted to the lowest KNN accuracy of 96.6% and the highest SVM accuracy of 98.01%, the Stacking approach demonstrates superior accuracy as 99.05%. [ABSTRACT FROM AUTHOR]

The Cloud environment had been the go-to for many users recently. Once request from users get submitted, cloud resources are put into action to fulfill the request. Scheduling is the primary task in cloud that needs to be up-to the mark for completing the requests swiftly. Multiple dynamic requests are submitted simultaneously by cloud users that necessitates precise and prompt scheduling in cloud. Scheduling in cloud may be hampered by various constraints, take for example the various QoS parameters that needs to be upheld. Though many researchers had proposed solutions for scheduling in cloud, improvisations can still be made by combining several QoS parameters that help attain optimized scheduling in cloud to boost the overall cloud performance. In this paper, we had proposed a Binary Grey Wolf Optimization (BGWO) algorithm to optimize the scheduling activity in cloud computing environment. The BGWO is a multi-heuristic algorithm where tasks are scheduled based on a fitness function, explicitly designed for achieving optimization goal. The fitness function that had been designed comprises of three prime parameters namely, the degree of imbalance (DoI), energy consumption and makespan. The performance efficiency of the proposed BGWO had been ascertained by comparing it with Oppositional based Grey Wolf Optimization algorithm (OGWO) and Mean Grey Wolf Optimization algorithm (Mean GWO) with respect to imbalance, energy and makespan parameters. The proposed algorithm had produced a cumulative improvement of 10.13% and 17.4% for makespan, 30.18% and 41.96% for DoI, 8.94% and 14.95% for energy consumption parameters. Detailed comparative results obtained had been described in the Results part of this research article. [ABSTRACT FROM AUTHOR]

The present study tests the accuracy of four models in estimating the hourly air temperatures in different agroecological regions of the country during two major crop seasons, kharif and rabi, by taking daily maximum and minimum temperatures as input. These methods that are being used in different crop growth simulation models were selected from the literature. To adjust the biases of estimated hourly temperature, three bias correction methods (Linear regression, Linear scaling and Quantile mapping) were used. When compared with the observed data, the estimated hourly temperature, after bias correction, is reasonably close to the observed during both kharif and rabi seasons. The bias-corrected Soygro model exhibited its good performance at 14 locations, followed by the WAVE model and Temperature models at 8 and 6 locations, respectively during the kharif season. In the case of rabi season, the bias-corrected Temperature model appears to be accurate at more locations (21), followed by WAVE and Soygro models at 4 and 2 locations, respectively. The pooled data analysis showed the least error between estimated (uncorrected and bias-corrected) and observed hourly temperature from 04 to 08 h during kharif season while it was 03 to 08 h during the rabi season. The results of the present study indicated that Soygro and Temperature models estimated hourly temperature with better accuracy at a majority of the locations situated in the agroecological regions representing different climates and soil types. Though the WAVE model worked well at some of the locations, estimation by the PL model was not up to the mark in both kharif and rabi seasons. Hence, Soygro and Temperature models can be used to estimate hourly temperature data during both kharif and rabi seasons, after the bias correction by the Linear Regression method. We believe that the application of the study would facilitate the usage of hourly temperature data instead of daily data which in turn improves the precision in predicting phenological events and bud dormancy breaks, chilling hour requirement etc. [ABSTRACT FROM AUTHOR]

Dimethyl ether (DME) and its blend of refrigerants (R429A, R435A, and R510A) are considered in this study's second law analysis as potential replacements for R134a. The performance of various refrigerants in a vapour compression refrigeration system is examined using the Design package CYCLE D. The software REFPROP 9.0 is used to extract all of the thermal and physical parameters of DME and its blend of refrigerants. The Second law performance parameters such as Efficiency Defects, Entropy generation and ExergyEfficiency are discussed. The refrigerants R429A and R510A are more energy efficient than R134a across a condensing temperature range of 30 to 55 °C at − 10 °C evaporation temperature. R134a was exceeded by R429A and R510A in terms of exergetic efficiency by 2.08 and 0.43%, respectively. In comparison to other losses in different components, the compressor's exergy loss is larger at 37–40% of the total exergy loss. By employing RE170 and its blends, the Vapour Compression Refrigeration System often performs better under the second law than R134a. The result shows that the efficiency defects in the compressor are the largest, followed by the condenser and evaporator. Thus, the design improvement of a compressor is of at most importance to improve the system performance by lowering the overall irreversibility. [ABSTRACT FROM AUTHOR]

Mathematically study mass transfer phenomena involving chemical reactions in the flow of Sisko Ferro nanofluids through the porous surface. Three ferronano particles, manganese-zinc ferrite (Mn1/2Zn1/2Fe2O4), cobalt ferrite (CoFe2O4), and nickel–zinc ferrite (Ni–Zn Fe2O4) are considered with water (H2O) and ethylene glycol (C2H6O2) as base liquids. Appropriate resemblance transitions are used to convert the governing system of a nonlinear PDE to a linear ODE. The Runge–Kutta method, as extended by the shooting technique, is used to accomplish the reduction governing equations. The effects of various associated parameters on fluid concentration and mass transfer rate are investigated: magnetic criterion (M), Siskofluid material factor (A), Solid volume fraction (ϕ) for nanofluids, permeability parameter (Rp), Chemical reaction criterion (γ), Brownian motion factor (Nb), and Thermophoretic parameters (Nt). The current findings indicate that the diffusion proportion of Sisko Ferronanofluid Ni–Zn Fe2O4–H2O and CoFe2O4–H2O is higher than that of Ni–Zn Fe2O4–C2H6O2 and CoFe2O4–C2H6O2 respectively but it is opposite in the case of Mn–Zn ferrite. The comparison study was carried out to validate the precision of the findings. [ABSTRACT FROM AUTHOR]

Abstra: Thermally stable erbium-doped barium tellurite [60TeO2–20ZnO–4BaF2–(16 − x)BaCO3–xEr2O3, 0 ≥ x ≤ 2] glasses have been investigated for their linear and nonlinear optical properties. Significant concentration-dependent effects of erbium have been observed in most of the properties. Structural changes have been related to the formation of non-bridging oxygen atoms. Non-monotonic changes in physical and optical properties around 0.75 mol% doping indicated the network breaking and void filling ability of rare earth ions. Radiative lifetime of 4I13/2 level increased with erbium concentration to 2.64 ms for x = 2, while the luminescence intensity for 1.5 μm emission corresponding to 4I13/2 → 4I15/2 transition decreased beyond 0.75 mol% indicating the concentration quenching effect in the sample. This indicates the need for suitable compositional tunability to achieve the maximum output at suitable doping levels of erbium. Samples showed reverse saturable absorption phenomena owing to two-photon absorption. Significant higher optical nonlinearity led to lower optical limiting thresholds with values between 2.749 and 3.930 × 1012 W/m2, indicating their effectiveness as good optical limiting materials along with their lasing ability. [ABSTRACT FROM AUTHOR]

The household heating and cooling system often use the capillary device. The use of the helical capillary eliminates the need for lightweight refrigeration devices in the system. Capillary pressure is noticeably affected by the capillary geometric parameters, such as length, mean diameter, and pitch. This paper is concerned with the effects of the capillary length on the performance of the system. Three separate length capillary tubes were used in the experiment. The data on R152a were studied under various conditions to assess the impact of varying the length. Maximum COP is obtained at an evaporator temperature of − 12 °C and capillary length of 3.65 m. The result is drawn that the system performance enhances when the capillary length is improved to 3.65 m when compared to 3.35 m and 3.96 m. As a result, as the capillary length increases up to a specific amount, the system's performance improves. The findings from the experiment were compared with those from the computational fluid dynamics (CFD) analysis. [ABSTRACT FROM AUTHOR]

Nanostructured electrode materials for supercapacitors have attracted research interest due to their high power density and long cycle life. Herein, porous flower-like magnetite (Fe3O4) nanostructures have been synthesized using ethylene glycol mediated iron alkoxide as a precursor material. The magnetite nanostructures are prepared by heating an iron alkoxide at 450 °C for 3 h under N2 atmosphere. The prepared porous nanostructure is polycrystalline with a high surface area of 186 m2 g−1 and existence of pores with a pore volume 6.6 nm. The electrochemical capacitance performance of Fe3O4 nanostructures has been evaluated. The high discharge capacitance is 183 F g−1 at 1 A g-1 with high capacitance retention of about 65% upon charge–discharge cycling after 5000 cycles have been observed. The high discharge rate and cyclic stability are attributed to the porous nature of the Fe3O4 nanostructures. As Fe3O4 is inexpensive, relatively non-toxic, and environmental friendly nature has potential application for supercapacitors. [ABSTRACT FROM AUTHOR]

High surface area, porous nanostructures have attracted research interest for supercapacitors due to their high power density and long cycle life. Herein, porous hematite (α-Fe2O3) nanostructures have been synthesized via ferrous oxyhydroxide (α-FeOOH) as a precursor material. The hematite (α-Fe2O3) nanorods have been prepared by heating α-FeOOH at 300 °C for 3 h under an air atmosphere. The prepared porous α-Fe2O3 nanorods are polycrystalline with a high surface area of 197 m2 g−1 with a pore diameter of 8.9 nm. The electrochemical capacitance performance of α-Fe2O3 nanostructures has been evaluated. The high discharge capacitance is 372 F g−1 at 1 A g−1 with high capacitance retention of about 83% observed upon charge–discharge cycling after 3000 cycles. The high discharge rate and cyclic stability are attributed to the porous nature and high surface area of α-Fe2O3 nanorods. As α-Fe2O3 is economic and environmentally friendly nature, it has potential application for supercapacitors. [ABSTRACT FROM AUTHOR]

A systematic study of structural, thermal, linear, and non-linear optical properties on 60TeO2–20ZnO–(16 − x)BaCO3–4BaF2–xTm2O3 (x = 0.25 to 2 mol%) glasses synthesized by melt-quenching technique is reported. Thermal stability of the samples was found to be around 100 °C, while their energy bandgap values varied between 3.08 and 3.57 eV. Measured properties showed a dominant effect of thulium ions in modifying the properties of the glassy matrix. Structural studies using Raman spectroscopy showed the presence of non-bridging oxygen (NBO) dominated by the matrix effect and also aided by the rare earth dopants, while the presence of hydroxyl impurities was elucidated from infrared spectroscopy. Optical absorption spectra showed characteristic thulium bands and the increment in spectroscopic quality factor calculated from measured absorption data indicating the lasing capability of the material. Luminescence spectra yielded two strong 3H4 → 3F4 and 3F4 → 3H6 emission transitions in the infrared region around 1460 nm and 1863 nm for all the samples, intensities of which were affected by increasing rare earth concentrations. Open aperture Z-Scan measurements indicated a reverse saturable absorption behavior for all the samples owing to two-photon absorption. Formation of more NBO led to the reduction of optical limiting threshold values from 3.91 × 1012 to 2.38 × 1012 W/m2 with thulium doping which indicated that this glass can be tuned to act as mid-infrared source as well as excellent optical limiter. [ABSTRACT FROM AUTHOR]

Slow evaporation solution growth technique was adopted to grow good quality urea salicylic acid (USA) single crystals. Single-crystal X-ray diffraction confirmed their cell parameters and corresponding space group. Density functional theory (DFT) calculation was utilized to assess the frontier molecular orbital (FMO) and natural bonding orbitals (NBO) of the USA compound. Theoretically calculated bandgap energy was slightly different from the measured value of 3.49 eV and is utilized in understanding the charge transfer taking place in the molecule. The sample showed a lower cutoff wavelength of 350 nm. FTIR confirmed the presence of relevant functional groups and was found to be thermally stable up to 117 °C. The specific heat capacity of the title compound was found to be 1.28 J/kg/K at 30 °C. Laser damage threshold energy of USA crystal was found to be 1.37 GW/cm2. The electrical behaviour of the crystal was analysed from dielectric measurements. The mechanical stability revealed that the title compound is a soft material. Third-order nonlinear optical property of USA compound was analysed using standard Z-scan technique, which showed better characteristics compared to various reported comparable crystals. [ABSTRACT FROM AUTHOR]

This review deals with the growth and characterization of various urea and urea derivative single crystals. Samples grown by various methods like slow evaporation, low temperature solution growth, slow cooling, and mechanical direction limitation method from aqueous solution have been discussed. Various properties of these samples have been summarized. Considering that numerous works have been carried out on urea-based crystals, this review is confined to urea and organic derivatives of urea single crystals only. Improved non-linear optical properties of certain urea crystals have been highlighted in this article. [ABSTRACT FROM AUTHOR]

Intergovernmental Panel on Climate Change (IPCC) promulgated a clear message that there have been many extreme weather and climate events observed globally since 1950, and these changes occurred mainly due to anthropogenic causes and emission of greenhouse gases. A computation study was carried out to assess the extreme temperature and rainfall events for the period 1984–2015 at the Indian Agricultural Research Institute, New Delhi by using ETCCDI indices through RClimDex software. The statistical significance of time series data and various calculated indices was done by linear regression as well as by Mann-Kendall test. Results indicated that annual mean maximum temperature decreased significantly at 0.019 °C/year and annual mean minimum temperature showed an increasing trend but without statistical significance. Alteration has happened in atmospheric properties, both physical and chemical over Delhi region during the period because of rapid urbanization and, increased concentration of aerosol. Fossil fuel/biomass waste burning, transportation of sand dust from Thar Desert, and reduction in incoming solar radiation have contributed both for fall in daytime temperature and rise in nighttime temperature. The changes in temperature would affect agricultural production through reduction in the rate of photosynthesis and excessive nocturnal respiration. Frequency and magnitude of coolest day (maximum temperature < 15 °C) and night (minimum temperature < 5 °C) have been rising at IARI, New Delhi. In the case of rainfall-based indices, annual rainfall (PRCPTOT), consecutive wet days (CWD), and number of days with rainfall ≥ 20 mm (R20) showed significant increasing tendency. Increasing trend in simple daily intensity index (SDII), rainy days (R2.5), and declining trend of consecutive dry days (CDD) indicates better distribution of rainfall. Nevertheless, increasing tendency in RX1day, RX5day, and R99p indicates possibilities of heavy rainfall events although the trend has been found insignificant. [ABSTRACT FROM AUTHOR]

The 1,2,3,4-tetrahydroisoquinoline derivative compound fused with thiophene (BDTTIQ) is synthesized by the slow evaporation solution growth method and characterized by SCXRD, 1H and 13C NMR techniques. In the synthesized compound, the tetrahydroisoquinoline fragment of BDTTIQ is almost in the half-chair conformation. A 3D supramolecular architecture is attained by intermolecular C-H...0 and C-H...71 interactions in the crystal structure. Molecular docking simulations are carried out to examine the inhibitory nature of the synthesized compound BDTTIQ against ARK1C3 protein. [ABSTRACT FROM AUTHOR]

This study investigated simultaneous heavy metals removal and anthracene biodegradation by Rhodococcus opacus at different initial anthracene concentrations in the range 50-200 mg L. The heavy metals tested were Fe(III), Cu(II), Zn(II), Cd(II), Ni(II), and Pb(II) at 10 mg L initial concentration: The organism was found to be well capable of removing the heavy metals along with high anthracene biodegradation efficiency. However, anthracene biodegradation rate by the organism was reduced due to these heavy metals. In addition, the heavy metals effect on R. opacus biomass growth followed the order: Cd > Ni > Pb > Cu > Zn > Fe. The total time to anthracene biodegradation increased from 144 to 216 h in the presence of Fe, Zn, Cu, or Pb, and it was up to 240 h in the presence of Cd or Ni. Compared with 70.2% (w/w) lipid accumulation by the bacterium in the absence of these heavy metals, a significant decline in the same was observed in the presence of the different heavy metals. These values were 41.2, 44.1, 52.1, 54.1, 58.6, and 63.1% (w/w) for Cd, Ni, Pb, Cu, Zn, and Fe, respectively. Field emission scanning electron microscopy integrated with energy dispersive X-ray spectroscopy and transmission electron microscopy of the biomass grown in the presence and absence of these heavy metals further confirmed a change in morphology of the bacterium due to the heavy metals. Fourier transmission infrared spectroscopy spectra of the biomass obtained during its growth in the presence and absence of the heavy metals confirmed the involvement of N-H, C-H bend, -CH-(C=O), C-N stretch, C-H and O-H bending, and -C-Cl groups on the biomass for heavy metal uptake by the bacterium. [ABSTRACT FROM AUTHOR]

In this study, Nostoc muscorum, a native cyanobacterial species isolated from a coal mining site, was employed to remove Cu(II), Zn(II), Pb(II) and Cd(II) from aqueous solution containing these metals in the mixture. In this multicomponent study, carried out as per the statistically valid Plackett-Burman design of experiments, the results revealed a maximum removal of both Pb(II) (96.3 %) and Cu(II) (96.42 %) followed by Cd(II) (80.04 %) and Zn(II) (71.3 %) at the end of the 60-h culture period. Further, the removal of these metals was attributed to both passive biosorption and accumulation by the actively growing N. muscorum biomass. Besides, the specific removal rate of these metals by N. muscorum was negatively correlated to its specific growth rate. For a better understanding of the effect of these metals on each other's removal by the cyanobacteria, the results were statistically analyzed in the form of analysis of variance (ANOVA) and Student's t test. ANOVA of the metal bioremoval revealed that the main (individual) effect due to the metals was highly significant ( P value <0.05) on each other's removal. Student's t test results revealed that both Zn(II) and Pb(II) strongly inhibited both Cu(II) removal ( P value <0.01) and Cd(II) removal ( P value <0.02). All these results not only demonstrated a very good potential of the cyanobacteria in the bioremoval of these metals but also the effect of individual metals on each other's removal in the multicomponent system. [ABSTRACT FROM AUTHOR]

Context: Adhesive capsulitis (AC) is a common musculoskeletal manifestation in elderly having long standing history of diabetes. This hinders the function of shoulder which is crucial in many activities of daily living. This painful, functional deficit may decrease the quality of life in elderly.Aims: The purpose of this study was to evaluate the impact of AC on quality of life in diabetic elderly subjects.Settings and Design: District government Hospital, Udupi; Dr. T. M. A. Pai, Udupi, Kasturba Hospital, Manipal; and the study design is cross-sectional design.Materials and Methods: Two hundred and thirty-three diabetic elderly patients were recruited from the settings based on cluster sampling. They were evaluated for pain and restriction of range of motion in the shoulder joint and were. Severity of condition was classified on Oxford shoulder score and quality of life was calculated by SF- 36.Statistical Analysis Used: Descriptive statistics and spearman's correlation coefficient done in SPSS.Results: Forty-nine percent of women had diabetic AC. Majority of the subjects without AC fell in average quality of life. Women with AC fell in unhealthy category, whereas men were clustered in the average category.Conclusions: Adhesive capsulitis was an important factor in reducing the quality of life of the elderly with diabetes. [ABSTRACT FROM AUTHOR]

Photocurrent measurements have been undertaken on bulk As40Te60-xInx glasses of different compositions. It has been found that the photocurrent increases with illumination, which can probably be understood on the basis of the large dielectric constant of these materials and also due to the presence of a larger number of positive defect states. Further, the composition dependence of the conductivity activation energy and the photosensitivity exhibit a maximum at x=12.5(〈r〉=2.65) and a minimum at x=15(〈r〉=2.70). Earlier investigations on As-Te-In glasses, such as high-pressure resistivity behavior, electrical switching, etc., have identified the compositions x=12.5 and x=15 as the rigidity percolation threshold (RPT) and the chemical threshold (CT) respectively. Based on this, the maximum and the minimum seen in activation energy and photosensitivity of As40Te60-xInx glasses at x=12.5 and x=15 can be attributed to RPT and CT respectively. [ABSTRACT FROM AUTHOR]

The systematic study of background radiation and the distribution of radionuclides in the environment of Nilgiris biosphere in South India, have been carried out with an objective of establishing reliable baseline data on the background radiation level of the region. Soil samples have been collected at various places of Kotagiri taluk in Nilgiris biosphere and are analyzed for radioactivity measurements of primordial radionuclides by 3"×3" NaI(TI) gamma-ray spectrometer. It is observed that the average activity of 232Th series, 238U series and 40K in soil samples is found to be 102 Bq.kg–1, 41 Bq.kg–1 and 229 Bq.kg–1, respectively which contributes to a total gamma-dose of 86 nGy.h–1. Results of this systematic investigation establish the existence of wide range of variation in 232Th series, 238U series and 40K activities, which may be attributable to the existence of wide variety of lithological compounds in the zone under study. The ambient gamma-radiation dose measured is found to vary from 91 to 193 nGy.h–1 with a mean of 142.8 nGy.h–1. The measured ambient gamma-dose is more than 50% of the dose calculated from soil activities, which is due to the higher cosmic ray contribution to the total dose in the environment. The data is compared with different places around the world and the results are discussed in this paper [ABSTRACT FROM AUTHOR]

Measurement of concentration of radon and thoron daughter products in various indoor environment covering four seasons of a year in Udagamandalam Taluk of Nilgiris biosphere has been carried out using a high volume air sampler to asses the inhalation dose to the population which delivers higher dose than the radon and thoron gas alone. The potential alpha-energy concentrations of the radon and thoron progeny ranged from 0.97 to 12.72 mWL and from 1.63 to 15.83 mWL with a geometric mean of 6.02 and 7.89 mWL, respectively, taking all seasons into account. These measurements have yielded a wealth of data on the variation among the indoor radon and thoron progeny in various places during different seasons. The radon and thoron progeny levels are higher in winter seasons and are less in summer season with autumn and spring data lie in between winter and summer. Using the dose conversion factor for indoor exposures given in UNSCEAR 93 report the internal equivalent dose to the inhalation of radon progeny is evaluated to be 1357 mSv.y–1 and the corresponding annual effective dose equivalent value has been found to be 2.13 mSv.y–1. It can be observed that the mean value of radon is higher than the Indian average. Also it is found the radon and thoron progeny levels are higher in the case of houses built with rock and granite and in tiled type houses of nearly 100 years old. The levels are less in the case of houses built with brick and cement. The observed results for different types of houses and seasons are discussed in this paper. [ABSTRACT FROM AUTHOR]

The gas collection measurement method was employed to determine radon activity concentrations in the water of Coonoor. Open well water, dam water and stream water have been investigated for their radon concentrations. It is observed that the highest radon concentration is in the open well water and the lowest in stream water. From these measurements, the corresponding annual effective ingestion dose is determined. [ABSTRACT FROM AUTHOR]

Cloud computing turns to be a big shift from the conventional perception of the IT resources. It is a transpiring computing technology that is increasingly stabling itself as the promising future of distributed on-demand computing. The processes comprised in it are the ones that act as a vital backbone and which strengthen the entire stream of cloud computing as a whole. In specific, Task scheduling is the one such phenomena that enhances the cloud computing in terms of performance. Hence task scheduling that is considered as a predominant one amidst others is what this paper comprises all about. Maximizing the profit via assigning the whole task to the virtual machine is what the problem of scheduling deals with. Although there prevails many more ways to resolve this problem, this paper explores one such solution that consumes lesser number of resources, having lower cost and much importantly consuming lesser energy. By making a profound research regarding this approach of scheduling so as to represent the multi-objective function, both lion optimization algorithm and gravitational search algorithm are hybridized. In spite of having certain drawbacks which could be avoided although, the brighter side relies the merits of making use of both lion search and gravitational search algorithm. There could be many means of measurement for computing the performance of the algorithm. The different algorithms that aid to depict the comparable study encompasses gravitational search algorithm, genetic algorithm and lion, particle swarm optimization. The experimental results serve as the evident for depicting the bitterness of our proposed algorithm compared to the prevailing approaches. As an unexplored path may seem trivial but is effective so does the betterment of our lion approach. [ABSTRACT FROM AUTHOR]

Urea p-nitrophenol, an organic nonlinear optical crystal was synthesized and grown adopting slow evaporation and seed rotation method. Single crystal X-ray diffraction study confirmed the formation of the desired crystal. High resolution X-ray diffraction study showed the defect nature of the crystal. The presence of functional groups in the material was confirmed by FTIR analysis. UV-Vis-NIR study indicates that the grown crystal has a wider transparency region with the lower cutoff wavelength at 423 nm. The grown crystal is thermally stable up to 120 °C as assessed by TG-DTA analysis. The optical homogeneity of the grown crystal was confirmed by birefringence study. The 1064 nm Nd-YAG laser was used to obtain laser induced surface damage threshold which was found to be 0.38, 0.25 and 0.33 GW/cm2 for (0 1 0), (1 1 − 1) and (0 1 1) planes, respectively. The dielectric study was performed to find the charge distribution inside the crystal. The hardness property of the titular material has been found using Vicker’s microhardness study. The optical nonlinearity obtained from third order nonlinear optical measurements carried out using Z-scan technique showed that these samples could be exploited for optical limiting studies. [ABSTRACT FROM AUTHOR]