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Investigation of launch power and regenerator placement effect on the design of mixed-line-rate (MLR) optical WDM networks
In recent years, owing to the consistent increase in volume and heterogeneity of the traffic, telecommunication networks have undergone significant innovations. Existing studies have shown that, by adopting a mixed-line-rate (MLR) strategy, wavelength division multiplexed (WDM) optical networks can cost-effectively respond to the diverse variety of traffic requirements which have heterogeneous service demands. However, due to the existence of physical layer impairments [specifically cross-phase modulation (XPM)], adjacent channels on different line rates may exhibit serious degradation of signal quality and optical reach. In such cases, launch power governs the bit-error rate as it affects both the signal and the noise power due to XPM. Therefore, an intelligent choice of launch power on different line rates can significantly reduce the network cost. Further, in MLR optical networks, trade-off between regenerator placement and the launch power attains importance and needs to be addressed. In this work, we investigate the launch power and regenerator placement effect on the design of a MLR WDM optical network. The obtained simulation results show that the network cost is (i) mainly controlled by power values of the 10/100/400 Gbps channels, and (ii) decreases for a cost model in which, compared to 10G transponders, high-bit-rate transponders have higher cost decay. Further, with a lower cost model, it is found that more numbers of regenerators can be deployed, simultaneously minimizing the network cost. 2017, Springer Science+Business Media New York. -
Alkali-activated concrete paver blocks made with recycled asphalt pavement (RAP) aggregates
This study was conducted to evaluate the feasibility of using recycled asphalt pavement (RAP) aggregates in alkali-activated concrete paver blocks. Due to drastic growth in road expansion projects in India, there is tremendous amount of RAP generated by milling and digging of existing bituminous roads. Even though RAP gets recycled in new bituminous roads, there is still large volume of this material that gets downgraded, especially in urban areas. Therefore, there is a need to effectively utilize the unused RAP in paving industry. Alkali-activated paver blocks were synthesized with fly ash (FLA), ground granulated blast furnace slag (GGBS), NaOH sol., Na2SiO3 sol., RAP and natural aggregates. Natural aggregates were substituted with RAP aggregates at replacement rates of 0 %, 25 %, 50 %, and 75 % by weight. The developed paver blocks were tested for water absorption, compressive strength, and abrasion resistance according to IS 15658: 2006 standard. The results of the laboratory study showed that inclusion of RAP aggregates in alkali-activated concrete reduce the compressive strength and abrasion resistance of the paver blocks. Though there is reduction in strength, developed paver blocks classified for use in pedestrian and non-motorized facility. The study also found that the use of RAP aggregates in paver blocks incur economic benefits. A maximum reduction of 25.8 % in production cost was observed for RAP inclusive alkali-activated paver blocks. Furthermore, the proposed method provides environmental benefits by reducing consumption of Portland cement and natural aggregates from quarries, and thus makes paving industry more sustainable and environment friendly. 2019 The Authors -
A comprehensive novel model for network speech anomaly detection system using deep learning approach
Network Intrusion Detection System (NIDS) is the key technology for information security, and it plays significant role for classifying various attacks in the networks accurately. An NIDS gains an understanding of normal and anomalous behavior by examining the network traffic and can identify unknown and new attacks. Analyzing and Identifying unfamiliar attacks are one of the big challenges in Network IDS research. A huge response has been given to deep learning over the past several years and novelty in deep learning techniques are also improved regularly. Deep learning based Network Intrusion Detection approach is highly essential for improved performance. Nowadays, Machine learning algorithms made a revolution in the area of human computer interaction and achieved significant advancement in imitating human brain exactly. Convolutional Neural Network (CNN) is a powerful learning algorithm in deep learning model for improving the machine learning ability in order to achieve high attack classification accuracy and low false alarm rate. In this article, an overview of deep learning methodologies for commonly used NIDS such as Auto Encoder (AE), Deep Belief Network (DBN), Deep Neural Network (DNN), Restricted Boltzmann Machine (RBN). Moreover, the article introduces the most recent work on network anomaly detection using deep learning techniques for better understanding to choose appropriate method while implementing NIDS through widespread literature analysis. The experimental results designate that the accuracy, false alarm rate, and timeliness of the proposed CNN-NIDS model are superior than the traditional algorithms. 2020, Springer Science+Business Media, LLC, part of Springer Nature. -
Phytochemical analysis and antioxidant activity of leaf extracts of some selected plants of the family acanthaceae
The present era of scientific research has witnessed an enumerable amount of evidences to showcase the immense potential of medicinal plants. In the present investigation, the phytochemical analysis of Phlogacanthus pubinervius T. Anderson., Adhatoda vasica (L.) Nees,Phlogacanthus thyrsiflorus Nees, Phlogacanthus curviflorus (Wall.) Nees, and Ruellia tuberosa L. was carried out for the different plants extracted with methanol. Analysis was carried out to estimate the quantity of phenols, carbohydrates, tannins, flavonoids and proteins. The antioxidant property of these plants were analysed using DPPH method. The concentration of the plant samples required to decrease the DPPH concentration by 50% was calculated by interpolation from linear regression analysis and denoted IC50 value (g/ml). The qualitative analysis showed the presence of alkaloids, tannins, saponins, proteins, carbohydrate and phenols in all the sample extracts. The highest amount of tannins and phenols was observed in P. thyrsiflorus. P. pubinervius (77.83%), A. vasica (74.81%), P. curviflorus (94.20%), and R. tuberosa (70.78%) which showed highest antioxidant activity of DPPH-scavenging at 150 g/ml of methanol extract. The high percent of scavenging activities of those plants add value to their medicinal properties. The presence of the high amount of phytochemical compounds suggests that the plants have high amount of medicinal compounds and can be extensively used to extract the natural compounds. Kripasana & Xavier (2020). This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited (https://creativecommons.org/licenses/by/4.0/). -
Attenuation parameters of polyvinyl alcohol-tungsten oxide composites at the photon energies 5.895, 6.490, 59.54 and 662 keV
The growing demand for lightweight, non-toxic and effective X-A nd ?-ray shielding materials in various fields has led to the exploration of various polymer composites for shielding applications. In this study, tungsten filled polyvinyl alcohol (PVA) composites of varying WO3 concentrations (0-50 wt%) were prepared by solution cast technique. The structural, morphological, and thermal properties of the prepared composite films were studied using X-ray diffraction technique (XRD), Scanning electron microscopy (SEM) and Thermogravimetric analysis (TGA). The AC conductivity studies showed the low conductivity property of the composites. The X-ray (5.895 and 6.490 keV) and ?-ray (59.54 and 662 keV) attenuation studies performed using CdTe and NaI(Tl) detector spectrometers revealed a noticeable increase in shielding efficiency with increase in filler wt%. The effective atomic number (Zeff) calculated by the direct method agreed with the values obtained using Auto-Zeff software. The % heaviness showed that tungsten filled polyvinyl alcohol composites are lighter than traditional shielding materials. 2020 M V Muthamma et al., published by Sciendo 2020. -
Digital Marketing Strategies: Effectiveness on Generation Z
The paper examines the constructs of digital marketing strategies on two aspects. Exploring the numerous digital marketing strategies related to Generation Z through a comprehensive desk review and archival research and confirming the explored factors to create a valid and measurable instrument.It is important to quantify and develop a scale to measure the effectiveness of digital marketing strategies on Generation Z. The first section of the study is exploratory factor analysis (EFA), establishing the effectiveness of digital marketing strategies on Generation Z. The second section deals with Confirmatory Factor Analysis (CFA), confirming the factors coined through exploratory factor analysis. The dimensions identified in the research can help marketers create exclusive digital marketing strategies to target Generation Z. 2020 SCMS Group of Educational Institutions. All rights reserved. -
Relation between electricity consumption and economic growth in Karnataka, India: An aggregate and sector-wise analysis
Karnataka is a highly progressive and rapidly growing state in India, with huge potential for industrial growth, however, it grapples with power deficits and other problems in electricity sector, which make it a good case study for Indian electricity sector. Given the importance of electricity in the urbanisation and growth process, the paper analyses the electricity consumption trend in Karnataka, examine its causality with economic growth at aggregate and sectoral levels using Granger causality test, and forecast the future electricity consumption applying Holt-Winters smoothening (no seasonality) technique. The general trend reflects higher consumption by the agricultural consumers, compared to the revenue-generating 'Industries' and 'Commercial' categories, mainly due to the policy of de-metering and providing 'free' power to agricultural consumers since late 1980s. The Granger causality tests reveal that there is no causality relation (neutrality hypothesis) between electricity consumption and economic growth in Karnataka, for total, agricultural and industrial consumption. This basically stems from the inaccurate measurements of agricultural consumption, higher dependence on captive generation, and poor quality grid supply. Finally, electricity consumption is predicted to be around 69,347 GW h by 2019?20. Future policies should focus on universal metering, reducing cross-subsidization, supplying good quality and reliable power to all sectors, and economical planning of resource-mix to achieve adequate, productive and efficient electricity consumption. 2020 Elsevier Inc. -
A census of young stellar population associated with the Herbig Be star HD 200775
The region surrounding the well-known reflection nebula, NGC 7023, illuminated by a Herbig Be star, HD 200775, located in the dark cloud L1174 is studied in this work. Based on the distances and proper motion values from Gaia DR2 of 20 previously known young stellar object (YSO) candidates, we obtained a distance of 335 11 pc to the cloud complex L1172/1174. Using polarization measurements of the stars projected on the cloud complex, we show additional evidence for the cloud to be at ?335 pc distance. Using this distance and proper motion values of the YSO candidates, we searched for additional comoving sources in the vicinity of HD 200775 and found 20 new sources, which show low infrared excess emission and are of age ?1 Myr. Among these, 10 YSO candidates and 4 newly identified comoving sources are found to show X-ray emission. Three of the four new sources for which we have obtained optical spectra show H ? in emission. About 80 per cent of the total sources are found within ?1 pc distance from HD 200775. Spatial correlation of some of the YSO candidates with the Herschel dust column density peaks suggests that star formation is still active in the region and may have been triggered by HD 200775. 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. -
Sectoral correlations and interlinkages: NSE
An efficient portfolio is a well-diversified portfolio that gives the investor opportunities to earn money and provide cover against risks. Understanding the intersectoral linkages and correlations among various sectors in a stock market will help an investor to diversify the portfolio and reduce risk efficiently. This study aims at examining the underlying linkages and correlations among eight sectors in the Indian National Stock Exchange (NSE) using a Granger causality test under VAR environment. The results of the study based on nine years' data from 2009 to 2018 show that an effective portfolio can have two classifications -stocks from Pharma and Media as group one (defensive stocks) and picks from IT, Bank, Financial Services, Realty, Auto and FMCG sector as group two (somewhat Cyclical). The study further proves that the usual definition for cyclical and defensive sectors have undergone some profound changes. 2020 SCMS Group of Educational Institutions. All rights reserved. -
The Consortium on Vulnerability to Externalizing Disorders and Addictions (c-VEDA): an accelerated longitudinal cohort of children and adolescents in India
The global burden of disease attributable to externalizing disorders such as alcohol misuse calls urgently for effective prevention and intervention. As our current knowledge is mainly derived from high-income countries such in Europe and North-America, it is difficult to address the wider socio-cultural, psychosocial context, and genetic factors in which risk and resilience are embedded in low- and medium-income countries. c-VEDA was established as the first and largest India-based multi-site cohort investigating the vulnerabilities for the development of externalizing disorders, addictions, and other mental health problems. Using a harmonised data collection plan coordinated with multiple cohorts in China, USA, and Europe, baseline data were collected from seven study sites between November 2016 and May 2019. Nine thousand and ten participants between the ages of 6 and 23 were assessed during this time, amongst which 1278 participants underwent more intensive assessments including MRI scans. Both waves of follow-ups have started according to the accelerated cohort structure with planned missingness design. Here, we present descriptive statistics on several key domains of assessments, and the full baseline dataset will be made accessible for researchers outside the consortium in September 2019. More details can be found on our website [cveda.org]. 2020, Springer Nature Limited. -
Synthesis of Quinoxalin-2(1 H)-ones and Hexahydroquinoxalin-2(1 H)-ones via Oxidative Amidation-Heterocycloannulation
A metal-catalyst-free synthesis of substituted quinoxalin-2-ones from 2,2-dibromo-1-arylethanone by employing an oxidative amidation-heterocycloannulation protocol is reported. The substrate scope of the reaction has been demonstrated and a possible mechanism for this reaction has also been proposed. 2020 GeorgThieme. All Rights Reserved. -
Econophysical bourse volatility-Global Evidence
Financial Reynolds number (Re) has been proven to have the capacity to predict volatility, herd behaviour and nascent bubble in any stock market (bourse) across the geographical boundaries. This study examines forty two bourses (representing same number of countries) for the evidence of the same. This study finds specific clusters of stock markets based on embedded volatility, herd behaviour and nascent bubble. Overall the volatility distribution has been found to be Gaussian in nature. Information asymmetry hinted towards a well-discussed parameter of 'financial literacy' as well. More than eighty percent of indices under consideration showed traces of mild herd as well as bubble. The same indices were all found to be predictable, despite being stochastic time series. In the end, financial Reynolds number (Re) has been proved to be universal in nature, as far as volatility, herd behaviour and nascent bubble are concerned. 2020 Bikramaditya Ghosh et al., published by Sciendo 2020. -
Physical framework for a counselling environment in India: Thematic analysis of counsellors' perceptions
The influence of the physical environment on the counselling process is an inevitable part of a counselling session. However, there is little insight in Indian research into the desirable elements of the physical environment of the counselling room that helps facilitate a counselling session. Interviews were conducted with 10 professional counsellors in India. Thematic analysis of the databrought out various Basic and Organising themes under the following three Global themes: (a) Elements of the physical framework; (b) Counsellor's perspectives about the physical framework in counselling; and (c) Motivation to build a framework. The findings show how counsellors can systematise the physical framework to help construct the counselling session effectively. 2020 British Association for Counselling and Psychotherapy -
Significance of exponential space- and thermal-dependent heat source effects on nanofluid flow due to radially elongated disk with Coriolis and Lorentz forces
In this paper, the nanofluid flow near an infinite disk which stretches in the radial direction in the presence of exponential space-based heat source (ESHS) and thermal-based heat source (THS) is investigated. The Brownian motion and thermophoresis effects are accounted to study the nanofluids. Effects of radial magnetism and the Coriolis force are also deployed. The pertinent nonlinear equations are approximated under boundary layer notion and modified von Km transformations. The subsequent nonlinear differential system is treated via shooting method. The impacts of controlling parameters on flow profiles are discussed and depicted with the aid of graphs. Results show that as the ESHS and THS parameters increase, the thermal field increases. However, ESHS phenomenon is highly influential than THS phenomenon on energy transport and its gradient. Further, it is found that thermophoresis slip mechanism has more effect on heat transport rate than the Brownian motion. 2019, Akadiai Kiad Budapest, Hungary. -
Study of generator shaft behaviour during subsynchronous resonance using finite element method
Scientific research in electric power stations includes various online monitoring and control of equipments. Turbine and generator plays a key role in generating power. Frequency response analysis of the shaft which connects turbine and generator is used to detect the steady state response. It will enable the user to understand and design the system in such a way that it can withstand resonance, fatigue and other vibrations. Subsynchronous resonance which arises during line compensation by series capacitors increases oscillations in the turbine generator shaft system. The oscillations developed at low frequency causes physical damage to the shaft. There are several real time monitoring of the rotor shaft and turbine shaft misalignment by using laser technologies. The aim of this research paper is to use frequency response and modal analysis technique to detect the stress in the shaft and improve the design of it. A viscous damper is designed in the 3D model at the point of highly stressed area to control the resonance effect caused by series capacitors. 2020, Levrotto and Bella. All rights reserved. -
Simple and Efficient Amberlite 15-catalyzed Synthesis of Dihydroquinazolinones
Abstract: The Amberlite 15 catalyzed synthesis of substituted 2,3-dihydroquinazolin-4(1H)-ones was reported. The reaction conditions were optimized by screening in different solvents and catalysts. The substrate scope of the reaction was also studied, and a plausible mechanism for the reaction was proposed. 2020, Pleiades Publishing, Ltd. -
Transport studies of ionic solutes through chitosan/chondroitin sulfate A (CHI/CS) polyelectrolyte multilayer membranes
Nano scale assembling has led to the capability to directly control and enhance the capabilities and properties of a material through change of its structural makeup at the nano scale. A novel class of functional layers in which various properties can be tunable via in situ modifications of nanostructure through stimuli such as pH, capping, and salt addition provides a promising strategy to develop polyion responsive polyelectrolyte multilayer membranes (PEM's). The concentration (diffusion dialysis) and pressure dependent (ultrafiltration) studies of solution containing polyvalent ions through the chitosan/chondroitin sulfate A (CHI/CS) multilayers fabricated on ultipore membrane have been studied. The characterization of the bilayer pair was done with analytical instruments like ATR-FTIR, spectroscopic ellipsometry, SEM, AFM and finally TGA for water holding capacity. The characterization of bilayer pairs demonstrated the stability and integrity of bilayer pair. An important bilayer property such as water holding capacity and ion permeability across it was examined and a positive correlation was found with increase in number of bilayers. The possibility of capping a fabricated bilayer with another polyelectrolyte, polyethylene glycol (PEG) was used to examine the extend of efficiency. The permeation rate of ions across bilayers increased with makeup salt concentration was observed with capping. An increase in selectivity was observed with increase in the number of bilayers for Na+/Cu2+, Na+/Ag+ and Na+/Mn3+. 12.5 hybrid CHI/CS-PEG membranes shows a selectivity of 38.52 for Cl-/PO43- with a permeation rate of 37.54 10-5 cms-1 and 4.23 10-5 cms-1 respectively for Cl- and PO43-. The transport profile of a model vitamin, ascorbic acid (AA) through CHI/CS multilayers showed the capability of bilayer membrane for selective solute transport. 2020 The Author(s). Published by IOP Publishing Ltd -
On J-Colouring of Chithra Graphs
The family of Chithra graphs is a wide ranging family of graphs which includes any graph of size at least one. Chithra graphs serve as a graph theoretical model for genetic engineering techniques or for modelling natural mutation within various biological networks found in living systems. In this paper, we discuss recently introduced J-colouring of the family of Chithra graphs. 2020, The National Academy of Sciences, India. -
Conductivity/Electrochemical Study of Polyvinyl pyrrolidone-Poly(vinyl alcohol)/I3? Thin Film Electrolyte for Integrated Dye-Sensitized Solar Cells and Supercapacitors
Abstract: The current era focuses not only on producing solar energy but also preserving it for future use. Dye-sensitized solar cells (DSSC) and supercapacitors (SC) are such energy-based devices. DSSCs capture the solar energy and SCs store this captured energy. A natural anthocyanin dye extracted from Garcinia indica (kokum fruit) was used in the DSSCs. SnO2, one of the promising electrode materials for DSSC, was synthesized via a microwave technique. Blend polymer electrolytes (BPE) were prepared through a solution casting technique. A polyvinyl pyrrolidone (PVP) and polyvinyl alcohol (PVA) blend with varying concentrations of potassium iodide, along with iodine dopant, was prepared as a BPE electrolyte composition. The best of the PVA-PVP/KI composition was chosen using Nyquist plots of electrochemical impedance spectroscopy (EIS). Varying the temperature, the dielectric and conductivity study of the chosen composition was studied in detail. A fast/single-step synthesis technique, namely a laser-engraved approach, was used for few-layer graphene synthesis. This graphene serves as a common platform for the DSSC-SC integrated device: as a counter electrode in DSSC and graphene-graphene symmetric electrode in SC. A DSSC-SC integrated device was fabricated and characterized using various analytical and microscopy techniques. The integrated device showed a 0.42 fill factor and 0.56% efficiency. The discharge time for integrated DSSC-SC cells was found to be increased threefold. Graphical Abstract: [Figure not available: see fulltext.] 2020, The Author(s). -
The behaviour of trading volume: Evidence from money market instruments
This paper analyzed the impact of macro and non-macroeconomic factors on the trading volume of the certificate of deposits and commercial paper with regard to India during the monthly period from April 2012-March 2018 using the quantile regression approach. The results revealed that gross domestic product rate, Consumer Price Index, Economic Policy Uncertainty Index, the Volatility Index, and the Nifty index had a negligible impact on the trading volume of corporate bonds. However, interest rates and exchange rates did not influence the trading volume of corporate bonds. In the other context, gross domestic product rate, Consumer Price Index, interest rates, the Volatility Index, and movements in the Nifty index showed a negligible impact on the trading volume of commercial paper. However, the variations in the trading volume of commercial papers were not explained by exchange rates and Economic Policy Uncertainty Index. 2020, Associated Management Consultants Pvt. Ltd.. All rights reserved.