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RADON in GROUNDWATER of MAGADI TALUK, RAMANAGARA DISTRICT in KARNATAKA
Radon is a water-soluble radioactive noble gas produced from the alpha decay of 226Ra in uranium series. Its presence in drinking water and open air increases the risk of lung and intestinal cancers in human beings. In view of this, radon concentration in groundwater and its dose due to inhalation and ingestion to the population of Magadi taluk of Ramanagara district in Karnataka state, India was studied. The groundwater samples were analyzed for radon concentration using emanometry technique. The study showed that the radon concentration in this area varied from 27.4 1.0 to 167.5 3.9 Bq/L and the effective dose ranged from 104.2 2.7 to 636.2 11.0 ?Sv/a. The study also revealed that 95% of the 37 samples studied showed higher radon concentration compared to the UNSCEAR recommendation (40 Bq/L) and all the samples showed higher than the USEPA recommendation (11.1 Bq/L). Ten samples have concentration above the maximum permissible level prescribed by WHO (100 Bq/L). The groundwater samples are found to be slightly alkaline within the permissible limit of Indian Standards. 2018 The Author(s). Published by Oxford University Press. All rights reserved. -
Facile synthesis of novel antimony selenide nanocrystals with hierarchical architecture by physical vapor deposition technique
Stoichiometric antimony selenide (Sb 2 Se 3 ) nanocrystals have been successfully engineered by a facile physical vapor deposition method, employing a single precursor of polycrystalline Sb 2 Se 3 charge in a closed quartz ampoule under high vacuum without any foreign seed or extraneous chemical elements. This work underscores the efficacy of the vapor deposition process and provides synthetic strategies to scale down bulk Sb 2 Se 3 into novel nanostructures. The morphological evolution of the tailored architecture was examined on micro and nano size scales by scanning electron microscopy and high-resolution transmission electron microscopy. The intrinsic mechanism governing the nanostructure formation is revealed as layer-by-layer growth, related to the unique layered structure of Sb 2 Se 3 . The optical properties of the grown crystals were probed by UVvisNIR and photoluminescence tools. The band-gap values of the microfibers, nanorods, nanooctahedra and nanospheres estimated from UVvisNIR analysis are found to be 1.25, 1.47, 1.51 and 1.75 eV, respectively. Powder X-ray diffraction, energy-dispersive analysis by X-rays, X-ray photoelectron spectroscopy, Raman spectroscopy and photoluminescence studies confirmed the quality, phase purity and homogeneity of the as-grown nanostructures. The adopted physical vapor deposition method is thus shown to be a simple and elegant route which resulted in the enhancement of the band gap for the Sb 2 Se 3 samples compared with their counterparts grown by chemical methods. This approach has great potential for further applications in optoelectronics. International Union of Crystallography, 2019 -
Lattice thermal conduction in suspended molybdenum disulfide monolayers with defects
In this study, we investigated the effect of lattice defects comprising vacancies and boundaries on the lattice thermal conductivity (LTC), ? p , of suspended molybdenum disulfide monolayers (MLs) over a wide temperature range (1 < T < 500 K). Using the phonon Boltzmann formalism, the acoustic phonons were considered to be scattered by the sample and grain boundaries, isotopic impurities, vacancies, and other phonons via Umklapp and normal (N-) processes. ? p was evaluated using a modified Callaway model by considering the in-plane longitudinal acoustic and transverse acoustic phonons, and out-of-plane flexural acoustic phonon modes. We demonstrated the need to include the often neglected non-resistive N-processes when evaluating the LTC. Numerical calculations of the temperature dependence of the LTC for crystalline and polycrystalline MoS 2 MLs showed the dominance of sample-dependent scattering mechanisms at low temperatures (T < 100 K) and of phonon-phonon scattering at higher temperatures, where the N-processes played an important role. The effects of vacancies and boundaries were to alter the behavior and suppress the magnitude of the LTC. The suppression due to vacancies was greater in crystalline MLs with specular surfaces and in polycrystalline MLs with larger grain sizes. The calculations compared well with recent thermal conductivity data obtained for polycrystalline samples. The need for further investigations is suggested. 2018 Elsevier Ltd -
Handwritten tibetan character recognition using hidden markov model
The Tibetan language which is one of the four oldest and most original languages of Asia is elemental to Tibetan identity, culture and religion and it convey very specific social and cultural behaviors, and ways of thinking. The annihilation of the Tibetan language will have tremendous consequences for the Tibetan culture and hence it is important to preserve it. Tibetan language is mainly used in Tibet, Bhutan, and also in parts of Nepal and India. Tibetan script is devised based on the Devanagari model and Sanskrit based grammars. In this paper, a method for Tibetan handwritten character recognition based on density and distance feature detection is presents. To get a better classification result, images are converted into binary and noise removal is done by using Otzsos method. Features are extracted by normalizing the image based on distance and density of the pixel in the image. Finally, Hidden Markov Model is used for character classification. BEIESP. -
An investigation on structural, electrical and optical properties of GO/ZnO nanocomposite
Coupling of graphene oxide with metal oxide is an effective way to enhance the opto-electric properties of the composite. Herein, a hybrid structure of graphene oxide (GO) -Zinc oxide (ZnO) nanostructure was successfully designed and fabricated with varying concentrations of ZnO. The GO and ZnO nanoparticles were synthesized through Hummer's and simple precipitation method respectively. Structural and physiochemical properties were examined via X-ray powder diffraction, FTIR and UV-Vis spectroscopy. The XRD results of GO showed a peak at 2? of 12.02 with particles of size 6nm and inter layer spacing 0.87 nm. The XRD patterns of ZnO nanoparticles showed a hexagonal unit cell structure and the average dimension of the sample was calculated to be 15 nm. The band gap of the synthesized GO is found to be 5.1 eV and that of ZnO to be 3.07 eV with the help Tauc plot. The dependence of various concentration of ZnO on the electrical behaviour is discussed by an impedance analyzer in the frequency range 100Hz to 1MHz. The ZnO/GO composite with best results have been obtained for 20% and 60 % ratios of ZnO. The composite has high dielectric permittivity and low loss tangent values and is identified as a promising candidate for energy storage applications. 2019 The Authors. -
Parametric investigation on the tool wear while performing face milling on inconel 718 using round insert
Machining of Inconel 718 has become a material of great purpose in the machining industry. Since Inconel is considered to be a super alloy which possess high material property such as high thermal fatigue, high strength and high resistance to corrosion it is thus considered to be a material which is hard to machine. This paper gives an overview on the tool wear that takes place while machining. Machining was carried out in a CNC milling machine with the help of a tungsten carbide circular insert. The cutting parameters taken into consideration were cutting speed, feed rate and depth of cut. Tool wear was analysed with the help of tool makers microscope. Statistical analysis was done on the MINITAB 18 software by using regression analysis. The regression analysis was carried out by using Response Surface Methodology (RSM) the mathematical model for each individual response has been developed from regression equations considering analysis of cutting parameters as independent variables which was found to be significantly accurate. BEIESP. -
Experimenting with resilience and scalability of wifi mininet on small to large SDN networks
Today everything is getting digitized where people want to be wireless by all aspects. There is a high demand of WiFi in every sector. Highest influence on network planning of newly developed network infrastructure is of SDN to meet the futuristic needs of upcoming technology. As a result, newly developed networks have become more adaptive to dynamic circumstances along with enhanced flexibility. Being globally connected, it is inevitable to obtain adequate services from data centers through Wi-Fi support on SDN Networks, which is still a dream. Thus, the target of the experiment performed and presented by the authors of this paper is to implement WiFi support on SDN. Further, authors have also demonstrated the scalability and resilience of SDN based WiFi Network on Mininet by testing performance parameters in various dynamic scenarios. This paper will have a high impact on the end users as SDN technology can be implemented as last mile technology using WiFi SDN. BEIESP. -
A Note on the Rainbow Neighbourhood Number of Certain Graph Classes
A rainbow neighbourhood of a graph G is the closed neighbourhood N[v] of a vertex v? V(G) which contains at least one colored vertex of each color in the chromatic coloring C of G. Let G be a graph with a chromatic coloring C defined on it. The number of vertices in G yielding rainbow neighbourhoods is called the rainbow neighbourhood number of the graph G, denoted by r ? (G). In this paper, rainbow neighbourhood number of certain graph classes are discussed. 2018, The National Academy of Sciences, India. -
Investigation of speech synthesis, speech processing techniques and challenges for enhancements
The sound produced by any human being or instrument can be used for various applications using the concept of extraction or selection. Using this concept, virtual sounds are produced which is prime requirement for various speech synthesis applications. In this paper we review the different speech processing methodologies, parameters involved and the various applications based on the speech quality produced. Though an overview is given on the processing and involved parameter, priority is given to the speech enhancement application. This survey helps to identify the challenges involved in various processing technique involved in speech enhancement of healthy and disordered speech. These findings with different speech production and speech synthesis techniques will help to improve the quality in various application of speech to text (STT), text to speech (TTS), Automatic speech production (ASP) and Automatic speech recognition (ASR). Copyright 2019 American Scientific Publishers All rights reserved. -
Some New Results on the Rainbow Neighbourhood Number of Graphs
A rainbow neighbourhood of a graph G is the closed neighbourhood N[v] of a vertex v? V(G) which contains at least one coloured vertex of each colour in the chromatic colouring C of G. Let G be a graph with a chromatic colouring C defined on it. The number of vertices in G yielding rainbow neighbourhoods is called the rainbow neighbourhood number of the graph G, denoted by r?(G). Rainbow neighbourhood number of the complements and products of certain fundamental graph classes are discussed in this paper. 2018, The National Academy of Sciences, India. -
Effect of heat treated HNT on physico-mechanical properties of epoxy nanocomposites
Halloysite Nano Tubes (HNTs) are naturally occurring Kaolite group minerals having an aluminosilicate-layer in the form of nanotubes which are known to enhance the properties of the polymer matrix composites when effectively dispersed in the epoxy matrix phase. In this regard, the present work is carried out to fabricate the composite specimens by polymer stir casting techniques and evaluate the basic properties viz., density, hardness, tensile strength, flexural strength, impact strength and the microstructure using Transmission electron microscopy (TEM) for better morphological studies of the dispersions in the nanocomposites with a filler content of 0, 5 and 10 wt% of HNT's that are effectively treated at three temperature conditions viz., Room temperature (RT), 50 C and 70 C according to specified ASTM test methods selected after thorough investigations and review of literature. As per the experimental investigation, the mechanical properties of the nanocomposite increases by the incorporation of heat treated HNT. Further, the study revealed that the nano composite with a filler content of 10 Wt.% of HNT preheat treated at 50 C shows superior tensile and flexural strength, However the critical observation of the results reveal that the impact strength is maximum for Nano composites with a filler content of 5 Wt.% HNT pre heat treated at 70 C. The study of TEM images gives an overview of uniform dispersion of HNTs in the matrix phase owing to varying pre-treatment conditions. It is evident that the properties of the nanocomposite depends on the quantity of functional filler present and temperature of heat treatment. 2019 Elsevier Ltd -
Biodegradation studies of polyhydroxyalkanoates extracted from Bacillus subtilis NCDC 0671
The major characteristic feature that distinguishes polyhydroxyalkanoates (PHAs) from its synthetic counterparts is its biodegradability. PHAs are the only class of biopolymers reported to be 100% degradable under both aerobic and anaerobic conditions without production of any toxic residues. The biodegradability of PHAs is influenced by several factors like moisture, temperature, pH, surface area and molecular weight of the polymer. The rate of biodegradation varies greatly depending on the environment. Biodegradation studies were carried out using plating method and direct inoculation method using selected Bacillus strains. Fungal degradation of PHA sheets was assessed using Penicillium chrysogenum. Biodegradation of PHA sheets in different soil types like river valley, agricultural land and garden soil was investigated. The degree of PHA degradation in aqueous environment was studied by incubating the sheets in distilled water, sea water, fish tank water and pond water. The highest degradation rate was observed with agriculture land soil (35.47 0.13%) and fish tank soil (36.93 0.13%). The non-toxic nature of the soil incubated with PHA sheets was ensured using plant growth test. 2019, World Research Association. All rights reserved. -
A stochastic propagation model to the energy dependent rapid temporal behaviour of Cygnus X-1 as observed by AstroSat in the hard state
We report the results from analysis of six observations of Cygnus X-1 by Large Area X-ray Proportional Counter (LAXPC) and Soft X-ray Telescope (SXT) onboard AstroSat, when the source was in the hard spectral state as revealed by the broad-band spectra. The spectra obtained from all the observations can be described by a single-temperature Comptonizing region with disc and reflection components. The event mode data from LAXPC provides unprecedented energy dependent fractional root mean square (rms) and time-lag at different frequencies which we fit with empirical functions.We invoke a fluctuation propagation model for a simple geometry of a truncated disc with a hot inner region. Unlike other propagation models, the hard X-ray emission (>4 keV) is assumed to be from the hot inner disc by a single-temperature thermal Comptonization process. The fluctuations first cause a variation in the temperature of the truncated disc and then the temperature of the inner disc after a frequency dependent time delay.We find that the model can explain the energy dependent rms and time-lag at different frequencies. 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. -
Analysis of machining parameters for face milling of inconel 718 using response surface methodology
The machining of Inconel 718 which is a nickel based super alloy has become a material of great importance mainly in the aerospace industry. Reason being the materials possesses properties of increase in strength at elevated temperature, high resilience to chemical reaction and high wear resistance. Gaining optimum machining parameters have become a great concern in the manufacturing industry, where economy of machining plays a very important key role in the market. This paper gives an overview of the experimentation conducted on the basis of Response Surface Methodology (RSM). Regression equations have been developed for surface roughness, by taking into consideration the machining parameters like cutting speed, feed rate and depth of cut for face milling operation performed in CNC machine. RSM analysis was carried out with the help of Mini Tab 18 software. The Mathematical equation developed after regression analysis shows to be very efficient. BEIESP. -
Managing change, growth and transformation: Case studies of organizations in an emerging economy
Purpose: In view of dynamic and widespread economic transformation in emerging economies, managing organizational change and growth in this context deserves more research attention. The purpose of this paper is to examine how three organizations in different industries manage change, growth and transformation in their organizational ecosystem. Design/methodology/approach: The authors conducted in-depth interviews with the leadership of three organizations in different economic sectors in India, a country representing an emerging economy. The authors also reviewed historical data from these organizations. Three case studies illustrating the evolution of these organizations were developed from the data collected. Findings: Lessons and implications from the three case studies suggest the following key elements of effective organizational change mechanisms in an emerging economy: visionary entrepreneurial leadership; program quality excellence; scale growth and scope expansion; network capabilities; and sustainable stakeholders engagement. At the same time, this study also shows how these organizations manage change, growth and transformation in the context of a society with strong traditions and cultural norms. Research limitations/implications: Results and conclusions may be limited by the fact that the study is based on three case studies. Additional studies from a variety of industries with large numbers of participants will be helpful in more fully understanding the ways in which change, growth and transformation can best be developed and deployed in different organizational settings. Practical implications: The proposed model of organizational change in an emerging economy may assist organizational leadership in designing and sustaining their change efforts. Social implications: This study highlights the role of visionary entrepreneurial leadership and the impact of organizational growth mechanisms on organizational value delivery capabilities and organizational reputation. Originality/value: Lessons and implications of five growth steps of outstanding organizations in an emerging economy context provide valuable insight for organizational change, growth and transformation in other emerging contexts. 2019, Emerald Publishing Limited. -
Signature based key exchange for securing data and user from web data stealing attacks
Due to the immense technological growth, web and its related applications are becoming a major part of everyday life. The growth of the internet and technology not only increases the positive benefits but also increases negative activities such as data theft. As web applications are used frequently for many online services, it is the most common and valuable target for the adversary to host any web vulnerabilities. Data theft or data stealing attacks are quite common in the web and the internet with severe consequences. The private data are generally stored on the system which gives an opportunity for the attacker to steal the data from the storage or during transit. However, apart from stealing the critical data from the user, the attacker also steals the sensitive data from the web applications. This type of attack takes several forms for stealing perilous information from the user and web application. Unfortunately, these attacks are easy to execute as the attacker needs only the internet connection, a web server and technical knowledge which are readily available. Several prevention strategies exist to thwart the user and the application from the web attacks, however, they do not provide the complete solution. This paper presents the signature based key exchange to prevent the user as well as the web application from several variations of data stealing attacks through mutual attestation. The experimental results show that the proposed method prevents the user and application from data theft than any other existing methods. BEIESP. -
An efficient scheme for water leakage detection using support vector machines (SVM)-Zig
Water is one of the most essential and valuable resources for all living beings, yet in the present day, there is a scarcity of it. Half of the water loss in large cities and industries is due to leaks and illegal lines. 10%-20% of water loss can be reduced by detecting leaks but without the presence of advanced monitoring systems, this problem is typically worsened. Monitoring the consumption and leak detection for such large areas is a challenging task. To overcome this issue a small prototype is prepared called Zig. Zig is designed for both household and industrial purposes. Its main aim is to monitor the flow and consumption of water at different levels of a building like a first-floor and so on which may represent some industrial and household situation. This work focuses on pressure/flow monitoring method to reduce the operational cost and also to detect leakage. One of the machine learning algorithms, Support Vector Machines (SVM) has been applied to detect the leakage and it is compared with Random Forest algorithm to show that proposed scheme is detecting water leakage better. BEIESP. -
Adaptive uplink scheduling model for WiMAX network using evolutionary computing model
The increased usage of smart phones has led to increase usage an internet based application services. These application requires different quality of service (QoS) and bandwidth requirement. WiMAX is an efficient network to provision high bandwidth connectivity and coverage to end user. To meet QoS requirement the exiting model used adaptive model selection scheme. However, these model induce bandwidth wastage as it does not considers any feedback information for scheduling. This work present an Adaptive Uplink Scheduling (AUS) by optimizing MAC layer using Multi-Objective Genetic Algorithm (MOGA). The MAC scheduler use feedback information from both physical layer and application layer. Further, to meet QoS requirement of application and utilize bandwidth efficiently this paper presented an adaptive modulation selection scheme based on user application requirement using MOGA. Our model provides application level based QoS provisioning for WiMAX network. Experiment are conducted to evaluate performance of AUS over exiting model. The overall result attained shows AUS model attain good performance in term of throughput, successful packet transmission and packet collision. 2019 Institute of Advanced Engineering and Science. All rights reserved. -
On the Mass Accretion Rate and Infrared Excess in Herbig Ae/Be Stars
The present study makes use of the unprecedented capability of the Gaia mission to obtain the stellar parameters such as distance, age, and mass of HAeBe stars. The accuracy of Gaia DR2 astrometry is demonstrated from the comparison of the Gaia DR2 distances of 131 HAeBe stars with the previously estimated values from the literature. This is one of the initial studies to estimate the age and mass of a confirmed sample of HAeBe stars using both the photometry and distance from the Gaia mission. Mass accretion rates are calculated from H? line flux measurements of 106 HAeBe stars. Since we used distances and the stellar masses derived from the Gaia DR2 data in the calculation of the mass accretion rate, our estimates are more accurate than previous studies. The mass accretion rate is found to decay exponentially with age, from which we estimated a disk dissipation timescale of 1.9 0.1 Myr. The mass accretion rate and stellar mass exhibit a power-law relation of the form . From the distinct distribution in the values of the infrared spectral index, n2-4.6, we suggest the possibility of difference in the disk structure between Herbig Be and Herbig Ae stars. 2019. The American Astronomical Society. All rights reserved.. -
Benefits of cross training: Scale development and validity
Studies related to benefits of cross - training were mainly done either in the context of qualitative research or as comprehension of desk research. The literature scarcely covered the measurement issues, and thus, it became vital to quantify and develop a scale to measure the benefits of cross - training (BCT). Cross -training means training that covers multiple tasks within a department This training technique keeps employees prepared to handle more than a single Job for which they have been Initially hired. This concept Is also called 'worker multlfunctlonallty'. The study aimed to propose and validate an Instrument to measure BCT. The nrst section of the study was exploratory factor analysis (EFA) establishing the benefits of cross training through four dimensions namely Job Stability, Career Advancement, Networking, and Idle lime Management. Confirmatory factor analysis (CFA) was used in the second section to verify the factor structure of the observed variables. The results indicated that cross training the employees in an organization could help practitioners to adopt the same as a strategy in retaining the employees by saving on the costs of recruitment, selection, and staffing. The findings also suggested that cross training helped in securing a job, progressing in one's career, enabling better interaction among the employees, and efficiently managing the idle time in the organization. 2019, Associated Management Consultants Pvt. Ltd.. All rights reserved.