Browse Items (11810 total)
Sort by:
-
Launch power determination algorithm for dynamic traffic provisioning in mixed-line-rate optical wavelength division multiplexed networks
In transparent mixed-line-rate (MLR) optical networks, different line rates, on different wavelengths, can coexist on the same fibre. However, along the path, signal experiences various physical layer impairments (PLIs), and its quality also degrades. A major factor that affects transmission quality is launch power of the optical signal. On one hand, power must be high enough to ensure less noise at receiver; on the other hand, it must be lower than the limit where PLIs start to distort the signal. Further, high launch power is disruptive to both, the actual lightpath and its neighbours. In this study, we investigate the problem of determining appropriate launch power for provisioning dynamic connection requests in transparent MLR networks. We propose a heuristic that determines the appropriate launch power of a lightpath. The PLI-average (PLI-A) approach is based on the optical reach of signals, is practical, and can adapt to the needs of network operators. Results show that performances of the proposed approach are better than the existing schemes. Copyright 2015 Inderscience Enterprises Ltd. -
Mixed convection in the stagnation-point flow over a vertical stretching sheet in the presence of thermal radiation
An unsteady two-dimensional stagnation-point mixed convection flow of a viscous, incompressible dusty fluid towards a vertical stretching sheet has been examined. The stretching velocity and the free stream velocity are assumed to vary linearly with the distance from the stagnation point. The problem is analyzed using similarity solutions. The similarity ordinary differential equations were then solved numerical by using the RKF-45 method. The effects of various physical parameters on the velocity profile and skin-friction coefficient are also discussed in this paper. Some important findings reported in this work reveal that the effect of radiation has a significant impact on controlling the rate of heat transfer in the boundary layer region. -
Highly selective first order derivative spectrophotometric determination of osmium(VIII) using anthranilic acid as a chromogenic reagent
A simple, selective and sensitive spectrophotometric method has been developed for the determination of osmium(VIII) using anthranilic acid as a reagent in the presence of Triton X-100. The molar absorptivity and Sandells sensitivity of the violet coloured species are 3.03 104L mol-1cm-1 and 3.5 ng cm-2 respectively. Beers law is obeyed between 0.5-5.5 ?g mL-1 of Os(VIII) at 500 nm. The stoichiometry of the complex is found to be 1:2 (metal: ligand). Calibration graph for the first order derivative spectrophotometric determination of Os(VIII) is derived by measuring derivative amplitudes at 525 nm with a linear range 0.25-5.5 ?g mL-1. The detection limit and quantitation limit of first order derivative spectrophotometry are found to be 0.075 and 0.25 ?g mL-1, respectively.1 1The metal ions, which are normally associated with osmium in catalysts and alloy samples, do not interfere. The proposed method has been successfully applied for the trace level determination of osmium in various synthetic mixtures containing commonly associated metal ions and corresponding to the alloy composition. 2015, National Institute of Science Communication and Information Resources (NISCAIR). All rights reserved. -
K? to K? X-ray intensity ratios and K to L shell vacancy transfer probabilities of Co, Ni, Cu, and Zn
The K to L shell total vacancy transfer probabilities of low Z elements Co, Ni, Cu, and Zn are estimated by measuring the K? to K? intensity ratio adopting the 2?-geometry. The target elements were excited by 32.86 keV barium K-shell X-rays from a weak 137Cs ?-ray source. The emitted K-shell X-rays were detected using a low energy HPGe X-ray detector coupled to a 16 k MCA. The measured intensity ratios and the total vacancy transfer probabilities are compared with theoretical results and others work, establishing a good agreement. 2015, Pleiades Publishing, Inc. -
SARDS: Secured anonymous routing with digital signature in wireless sensor network
A Wireless Sensor Network has witnessed a massive research towards security as well as energy efficiency in past decades. However, there are few studies that have witnessed a cost effective secure routing technique with energy effectiveness till date. Objectives: Our objective is to use public key cryptography for ensuring energy-efficient routing technique in Wireless Sensor Network. Method/Analysis: The proposed paper presents a technique called as SARDS (Secured Anonymous Routing with Digital Signature) that performs verification of the routing information exchanged among the sensors in Wireless Sensor Network. SARDS uses elliptical curve cryptography as the backbone of security formulations and performs authentication of all the communicating nodes present in the network. Findings: The system also allows a dual layer of security by introducing a novel signature based scheme towards public key encryption policy. The outcome of the study shows SARDS to excel best in performance in comparison of existing security and energy efficient routing schemes. Application/Improvements: Proposed SARDS technique offers 1) A novel public key encryption, 2) A novel digital signature scheme, and 3) A novel privacy or anonymous scheme. The outcome of the proposed system is also found to be superior as compared to existing protocols e.g. SecLEACH, LEACH and PEGASIS. -
A survey on next-generation mixed line rate (MLR) and energy-driven wavelength-division multiplexed (WDM) optical networks
With the ever-increasing traffic demands, infrastructure of the current 10 Gbps optical network needs to be enhanced. Further, since the energy crisis is gaining increasing concerns, new research topics need to be devised and technological solutions for energy conservation need to be investigated. In all-optical mixed line rate (MLR) network, feasibility of a lightpath is determined by the physical layer impairment (PLI) accumulation. Contrary to PLI-aware routing and wavelength assignment (PLIA-RWA) algorithm applicable for a 10 Gbps wavelength-division multiplexed (WDM) network, a new Routing, Wavelength, Modulation format assignment (RWMFA) algorithm is required for the MLR optical network. With the rapid growth of energy consumption in Information and Communication Technologies (ICT), recently, lot of attention is being devoted toward "green" ICT solutions. This article presents a review of different RWMFA (PLIA-RWA) algorithms for MLR networks, and surveys the most relevant research activities aimed at minimizing energy consumption in optical networks. In essence, this article presents a comprehensive and timely survey on a growing field of research, as it covers most aspects of MLR and energy-driven optical networks. Hence, the author aims at providing a comprehensive reference for the growing base of researchers who will work on MLR and energy-driven optical networks in the upcoming years. Finally, the article also identifies several open problems for future research. 2015 by De Gruyter. -
Influence of grandparents on the emotional intelligence of early adolescents in Kerala
Children find unique acceptance in their relationships with grandparents, which benefits them emotionally and mentally. The presence of grandparents in the family can be a source of great support for other family members, especially children and adolescents. They are often role models, playmates and mentors for younger generations. The aim of the study is to compare emotional intelligence of adolescents with regard to the influence of grandparents through a quantitative research design. The sample taken for this research comprised of 427 adolescents of VIII to XII standards, among which 278 were from nuclear families and 149 from three generation families. They belonged to ten different government aided urban state syllabus English medium schools in Kerala. Mangal Emotional Intelligence Inventory was used to yield the total score and four dimensional scores in areas of Intrapersonal awareness, Interpersonal awareness, Intrapersonal management and Interpersonal management in adolescents. An independent sample t-test between two types of families indicated that grandparents have an influence on the emotional intelligence of adolescents. Journal of the Indian Academy of Applied Psychology. -
Discontinuities in the trajectory of solar photovoltaic (SPV) technology development in India
The objective of this paper is to understand different phases of solar photovoltaic (SPV) technology in India and the interplay of scientific, technological, economic, and political factors in each of the phases. There are four distinct phases. In the first-phase (1947-1970), SPV technology was recognized as an important source of energy for countries like India. In the second phase (1971-1990), the oil crisis led to the formulation of new scientific and technological initiatives and programs in SPV, but due to a lack of political commitment the initiatives disintegrated. In the third phase (1991-2003), several factors seemed to have undermined the development of SPV sector. Currently in the fourth phase (2003 to the present), India has virtually lost the race for development of photovoltaic technology. Within the context of climate change and resource constraint, India has reformulated its strategy which has taken the form of the Jawaharlal Nehru National Solar Mission Plan (JNNSM).This paper examines how JNNSM influences indigenous attempts in photovoltaic technology development. The paper shows how scientific, technological, economic and political factors have contributed to discontinuities in the development of the technology. Koninklijke Brill Nv, Leiden 2015. -
Recognition and Understanding of Emotions in Persons with Mild to Moderate Mental Retardation
Deficits in intellectual ability have been linked to deficits in emotion understanding and consequently social competence. Research suggests that individuals with mental retardation exhibit deficits in their ability to identify emotional states in themselves and others, relative to normal mental age matched controls and peers and display an inability to decode facial expressions of emotion. Emotional experience is elicited in part by a cognitive appraisal of a situation toward a goal. However, the ecological validity of previous studies is limited. In this study we developed new materials to investigate the emotion understanding skills of persons with mild to moderate mental retardation. Six tasks included faces displaying emotion in context, comic strips, audio, video and audio-visual material of individuals expressing emotions in context. Results indicated that the mentally retarded were able to identify emotions in context than expressions without context and emotion understanding improved with increasing contextual cues and dynamic content. 2014, Springer India Pvt. Ltd. -
DFT electronic structure calculations, spectroscopic studies, and normal coordinate analysis of 2-[(5-nitro-1,3-thiazol-2-yl)carbamoyl]phenyl acetate
The solid phase FTIR and FT-Raman spectra of 2-[(5-nitro-1,3-thiazol-2-yl)carbamoyl]phenyl acetate (25N2LCPA) have been recorded 450-4000 cm-1 and 100-4000 cm-1 respectively. The normal coordinate analysis was carried out to confirm the precision of the assignments. DFT calculations have been performed giving energies, optimized structures, harmonic vibrational frequencies and IR intensities. The structure of the molecule was optimized and the structural characteristics were determined by density functional theory (DFT) using B3LYP method with 6-31+G(d,p) basis set. The detailed interpretation of the vibrational spectra has been carried out with aid of normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology. The Vibrational frequencies are calculated in the above method and are compared with experimental frequencies which yield good agreement between observed and calculated frequencies. Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using natural bond orbital (NBO) analysis. In addition, Frontiers molecular orbital and molecular electrostatic potential were computed by using Density Functional Theory (DFT) B3LYP/6-31+G(d,p) basis set. The calculated HOMO and LUMO energies show that charge transfer occurs in the molecule. 2014 Elsevier B.V. All rights reserved. -
Evaluation of relation of personality, parenting, stress and depression in patients with secondary amenorrhoea
Background: Relatively few studies have assessed psychosocial correlates for secondary amenorrhea. Our study of the Gynaecological condition concerning personality factor (on introversion-extroversion dimension), parenting (authoritarian and authoritative) style, depression and perceived stress addresses this gap in the literature. The study inquires, whether these variables are related. Aims and objectives: To evaluate the relation of personality, parenting, stress and depression in patients with secondary amenorrhoea. Methods: Evaluation was done for forty-four young-adult female patients (with their fathers alive) affected by secondary amenorrhea, requesting help for menstrual disorders. The Parental Authority Questionnaire administered on the parent of patients, and Beck Depression Inventory, Perceived stress scale, Kundu Introversion-Extraversion Inventory on patients. In addition to that sixty healthy participants were recruited. The 104 participants were divided into two groups according to the presence (44 cases) or the absence (60 cases) of clinically diagnosed secondary amenorrhea. Results: Appropriate use of correlation coefficient followed by a test of significance revealed significant correlations between the variables which were hypothesised in accordance and hadbeen discussedregarding future research. Conclusions: Secondary amenorrhea was found to be possibly associated with personality factors, stress, depression and the kind of parenting individuals receive during their lifetime. -
Effects of Processing Parameters on Microstructure Evolution of Al-7Si-Mg Alloy by Cooling Slope Casting
This work investigates the effects of pouring temperature, slope length, and slope temperature in cooling slope casting on the formation of globular microstructure of Al-7Si-Mg alloy. The remnant alloy on the slope during casting was quenched and characterized at different stages of flow to evaluate the microstructure features developed in cooling slope casting. The primary ?-Al dendritic phase found in conventional cast alloy was transformed into globular shape in slope-processed cast alloy. Finer and more homogenous primary ?-Al phase was formed at lower pouring temperature (625C). The effect of slope length on microstructure of Al-7Si-Mg alloy was significant at high pouring temperatures (640 and 660C) but was not visible at low pouring temperature (625C). The microstructure of alloy became coarser with increasing slope temperature. 2015, ASM International. -
Post-formalist explanation of academic achievement: Exploring the contribution of John Ogbu and Joe Kincheloe
The present paper attempts to interrogate the existing approach to understand academic achievement in the mainstream educational psychology. The paper explores the persistent question of "why academic achievement gap" in the modern society from the cultural ecological and postformalist framework of John Ogbu and Joe Kincheloe respectively. As mainstream educational psychology limits its scope in the narrowed individualistic lens, paper suggests that dominant identity based curriculum, pedagogy and knowledge may concretize the psychological categories unless revolutionary efforts are made to transcend the boundaries. Thus, paper adopts critical interdisciplinary framework, rejecting positivistic metatheory as an only relevant approach in educational psychology. -
Effect of solvents on photophysical properties and quenching of 2-{[3-(1H-benzimidazole-2-yl) phenyl] carbonoimidoyl}phenol
The effect of solvents of varying polarity on the absorption and fluorescence emission of the Schiff base, 2-{[3-(1H-benzimidazole-2-yl) phenyl]carbonoimidoyl}phenol, was studied using Lippert-Mataga bulk polarity function, Reichardt's microscopic solvent polarity parameter and Kamlet's multiple linear regression approach. The spectral properties follow Reichardt's microscopic solvent polarity parameter better than Lippert-Mataga bulk polarity parameter, indicating the presence of both general solute-solvent interactions and specific interactions. Catalan's multiple linear regression approach indicates the major role of solvent polarizability/dipolarity influence compared with solvent acidity or basicity. The solvatochromic effect was utilized to calculate the dipole moments of ground and excited states of the Schiff base using different methods. Bathochromic shift in the emission spectrum and the increase in dipole moment in the excited state signifies the intramolecular charge transfer character in the emitting singlet state. Fluorescence quenching by aniline was also studied in 1,4-dioxane and n-butanol, and the results were analyzed using sphere of action static quenching and finite sink approximation models. 2014 John Wiley & Sons, Ltd. -
Methodical investigation of filtering algorithms for human brain MRI
Retrieving useful information from the given data through a systematic and organized way can help to learn more about the data in a much better and clear way. Information is hidden in medical images. The medical images like Magnetic Resonance Images (MRI), Computed Tomography (CT), ultrasound, X-ray are suggested by the physicians depending upon the available symptoms of the disease. These medical images contain valuable information about a particular disease in hidden format. Identification of that potentially useful information is crucial in further treatments of a particular disease. In image mining the images are processed and extraction or mining of knowledge is done, to get original, valid, potentially useful, and understandable patterns from the available images. The obtained patterns are a good source for further research work. This research work uses brain Magnetic Resonance Images (MRI) of human beings. Different image filtering algorithms were used to retrieve noise free images. International Science Press. -
Psychological Components for Marital Distress and Divorce in Newlywed Indian Couples
The personal and family consequences of the ever-increasing ratio of divorce have focused global attention on formulating tactics to avert marital breakdown. However, the increase in the rate of divorce cases indicates that its core reasons have not yet been tackled. The most recurrently asked question in the literature around divorce is this: Why do couples shatter so soon, even after marrying with high prospects? This study endeavors to find answers for this question from a family psychological perspective. Using a basic interpretative qualitative method and phenomenological research paradigm, this study has provided very personal experiences of 20 newlywed divorced participants and also their sole vision on crucial key psychological factors for marital distress and divorce. One superordinate theme derived in the analysis involves intrapsychic resistance to accommodate life cycle transitions. This research has vital inferences for identifying the challenges faced by contemporary couples on the newlywed life cycle transition. , Copyright Taylor & Francis Group, LLC. -
Optimization of multiple responses using overlaid contour plot and steepest methods analysis on hydroxyapatite coated magnesium via cold spray deposition
In this work, sequential optimization strategy based statistical design was employed to enhance the mechanical properties of hydroxyapatite coatings onto a pure magnesium substrate using a cold spray technique. A fractional factorial design (24-1) was applied to elucidate the process parameters that significantly affected the mechanical properties of the coating samples. Standoff distance, surface roughness, and substrate heating temperature were identified as important process parameters affecting thickness, nanohardness, and the elastic modulus of the coating sample. The overlaid method analysis was employed to determine tradeoff optimal values from multiple regressive equations. Then, finally, steepest method analysis was used to reconfirm and relocate the optimal domain from which the factor levels for maximum mechanical properties of the coating were determined at 49.77mm standoff distance, 926.4grit surface roughness, and 456C substrate heating temperature, which can accommodate the optimum requirements for the cold spray process with a coating of 49.77?m thickness, 462.61MPa nanohardness, and 45.69GPa elastic modulus. Scanning electron microscopy revealed that a short standoff distance, high surface roughness, and high substrate temperatures improved the bond between the coated layers and substrates. 2015 Elsevier B.V. -
Causality among Energy Consumption, CO2 Emission, Economic Growth and Trade: A Case of India
The present study attempts to examine the causal nexus between energy consumption, CO2 emissions, economic growth and trade in India using the Perron (1989) unit root test, Gregory and Hansen (1996) cointegration test and vector error-correction model (VECM). The study results exhibit a long-run relationship between energy consumption, CO2 emissions, economic growth and trade in India. The empirical results confirm that energy consumption influences the economic activity in the short run, implying that higher rate of economic growth is driven by consumption demand for energy in the economy. This is also well in consistence with the findings of Paul and Bhattacharya (2004) in the Indian context. Further, the study detects one-way causation that exists from energy use to CO2 emission and trade, and CO2 emissions to economic growth in the short run. 2015 Indian Institute of Foreign Trade. -
Cold spray deposition of hydroxyapatite powder onto magnesium substrates for biomaterial applications
A simple, modified, cold spray process was developed in which hydroxyapatite powder was coated onto pure magnesium substrates preheated to 350 or 550C and ground to either 240 or 2000 grit surface roughness, with stand-off distances of 20 or 40 mm. The procedure was repeated five and 10 times. The hydroxyapatite coatings did not show any phase changes. Atomic force microscopy revealed a uniform coating topography, and scanning electron microscopy revealed good bonding between the coated layers and the substrates. As the p values were < 0.05, all factors except the number of sprays were considered to be significant. The response optimiser indicated that a 22.7 mm stand-off distance, a 649.2 grit surface roughness and a 496C substrate heating temperature produced good hydroxyapatite coatings of 46.3 ?m thickness, 436.5 MPa nanohardness and 43.9 GPa elastic modulus. The modified cold spray technique with substrate heating showed promising results in terms of product coating thickness and mechanical properties. 2015 Institute of Materials, Minerals and Mining. -
Novel splitring resonator antennas for biomedical application
Our paper presents the design and development of split ring resonator based metamaterial antenna for biomedical i.e., Industrial, Scientific and Medical(ISM-2.45GHz) applications and also used in biosensors. Now a day the biological changes in the human body such as glucose content in blood, heart rate, respiratory rate, brain tumor are monitored by the use of wireless body area networks. In such networks the main part of the system is antenna with compactness and wider bandwidth. We have designed gain enhanced and wide bandwidth antennas with size reduction of more than 95% compared to the conventional patch antenna. The design methodology is based on Metamaterial which is an emerging technology uses split ring resonators for size reduction. We have designed double square split ring shape superstrate antenna and circular ring resonator antenna with stub for 2.48GHz. Also they have better return loss (>12dB). Our antennas are fed with microstrip feeding and Coplanar Waveguide (CPW) feeding for better impedance matching and easy fabrication. The fabricated antennas are tested using Network analyzer. The measured results are good in agreement with simulated results. 2015, Journal of Pure and Applied Microbiology. All rights reserved.