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Rate Adaptation Mechanism for Multirate WLAN with Background Traffic Awareness
In recent times wireless communication has become more popular with its commercial usage. WLAN has evolved over the years to facilitate wireless communications for commercial usage. IEEE 802.11 working group focuses on developing global standards that can support the WLAN evolution. There are many features that IEEE 802.11 working group emphases on to provide the best experience for the Wi-Fi user. The popularity of Wi-Fi among commercial users has demanded more importance in terms of traffic and congestion. IEEE 802.11 have come with many updates enhancing with additional spectrum space, method of spectrum utilization, and so on. There are a few aspects of Wi-Fi adoption that have been kept outside the scope of the 802.11 standards, which are open for research. Wi-Fi rate adaptation is one of newlinethe important aspects of research. Many researchers have contributed with effective newlinemethodologies to improve user experiences. The literature review proves the importance of rate adaptation in the performance of wireless communication. The different version of the IEEE 802.11 standard provides a set of transmission rates to choose from for single-stream transmission. It is important to switch the transmission rate dynamically for more efficient utilization of the physical medium in a fluctuating environment. Dynamically identifying the optimal transmission rate from a list of single-stream transmission rates is a tedious task. There are different causes for the change in channel conditions and packet loss in the network. Identifying the best data transfer rate for the next transmission is a tedious task in such a network. It requires identification of the exact cause of loss. Improper channel estimation may lead to the channel may be underutilized or overused. Both situations will degrade the newlineperformance of the network. Evaluating and identifying the latest channel condition is newlineimportant. -
RASK: Request authentication using shared keys for secured data aggregation in sensor network
Accomplishing a robust security features to resists lethal attacks is still an open research area in wireless sensor network. The present paper review existing security techniques to find that there is still a trade-off between cryptographic-based security incorporations and communication performance. Moreover, we have identified that majority of the existing system has not emphasized on first line of defense i.e. security the route discovery process that can act as a firewall for all forms of illegitimate nodes existing in the network. The proposed study introduced RASK i.e. Request Authentication using Shared Key, which is a novel concept developed using simple quadratic formulation of generating keys for encrypting the message during data aggregation. The study outcome has been significantly benchmarked with recent studies and existing cryptographic standards to find RASK outperform existing techniques. Springer International Publishing AG 2017. -
Rare-earth-activated phosphor for laser lighting
The chapter describes that Y2Ba3B4O12 doped with europium ions were synthesized by a modified conventional solid-state reaction method. The formations of the phosphor crystal structure are confirmed via the X-ray diffraction technique. The luminescence measurement upon excitation in ultraviolet and emission in visible range shows the characteristics of Eu3+ excitation and emission. The occurrence of the charge transfer band is explained in detail. The emission spectrum of Eu3+ ions consists mainly of several groups of lines in the 550-725nm region, due to the transitions from the 5D0 level to the levels 7FJ (J=0, 1, 2, 3, 4) of Eu3+ ions. The phenomena of concentration quenching are explained on the basis of electron-phonon coupling and multipolar interaction. The purity of the red emission is also checked, and it makes Eu3+-doped poly-borate-based phosphor as a promising candidate for laser lighting application. 2022 Elsevier Inc. All rights reserved. -
Rapid Prototyping Methods in Manufacturing of Biomedical Implants: A Review
The advancements in science and technology have given the flexibility in various levels for the scientists to manufacture variety of components. Rapid prototyping is one of the most sought-after techniques in the field of biomedical engineering for material manufacture. Bio-inertness, biocompatibility, and manufacturability are the desirable properties for biomedical applications. The review aims to provide a valuable contribution to the biomedical field, by identifying and comparing the rapid prototyping methods on the basis of time, quality, and cost. This work is dedicated to study, identify, and compare different methods of rapid prototyping in the manufacture of biomedical implants, the materials used for these processes. It also encompasses comparison of the process parameters for each manufacturing method and the advantages and disadvantages of the processes. Polysiloxane, hydroxyapatite, bioceramics, and titanium alloys due to its bio-inertness and nontoxic nature are some of the identified materials in the current review of the research. The highly sophisticated and complex biomedical implant manufacturing by various methods was studied and compared. Immense researches are being carried out in this novel field and are more prevalent in biomedical field due to its beautiful characteristics. The rapid advanced technological methods facilitate immediate intervention and faster treatment of the patient which reduces the risk and helps in faster recovery. 2020, Springer Nature Singapore Pte Ltd. -
Rapid Eye Movement (REM) Sleep Behavior Disorder and REM Sleep with Atonia in the Young
Background: Rapid eye movement (REM) sleep behavior disorder (RBD) and REM sleep without atonia (RWA) have assumed much clinical importance with long-term data showing progression into neurodegenerative conditions among older adults. However, much less is known about RBD and RWA in younger populations. This study aims at comparing clinical and polysomnographic (PSG) characteristics of young patients presenting with RBD, young patients with other neurological conditions, and normal age-matched subjects.Methods: A retrospective chart review was carried out for consecutive young patients (<25 years) presenting with clinical features of RBD; and data were compared to data from patients with epilepsy, attention deficit hyperactivity disorder (ADHD), and autism, as well as normal subjects who underwent PSG during a 2-year-period.Results: Twelve patients fulfilling RBD diagnostic criteria, 22 autism patients, 10 with ADHD, 30 with epilepsy, and 14 normal subjects were included. Eight patients with autism (30%), three with ADHD (30%), one with epilepsy (3.3%), and six patients who had presented with RBD like symptoms (50%) had abnormal movements and behaviors during REM sleep. Excessive transient muscle activity and/or sustained muscle activity during REM epochs was found in all patients who had presented with RBD, in 16/22 (72%) autistic patients, 6/10 (60%) ADHD patients compared to only 6/30 (20%) patients with epilepsy and in none of the normal subjects.Conclusion: We observed that a large percentage of young patients with autism and ADHD and some with epilepsy demonstrate loss of REM-associated atonia and some RBD-like behaviors on polysomnography similar to young patients presenting with RBD. 2019 The Canadian Journal of Neurological Sciences Inc. -
RAO, R. RAJ (1955-)
[No abstract available] -
Ranjith cinemas - An episteme that create discourse on class, caste and religion /
Films are an important form of mass communication in India today. Apart from being mode of entertainment, films also shape the ideology in the mind of viewers because cinema is an ideological apparatus by nature of its very seamlessness. The audience do not see how the cinema creates ideology it invisibly renders and naturalizes it. -
Randomized Trials of Psychotherapeutic Treatment for Psychogenic Seizures: Scoping Review
Background: Psychotherapy improves seizure frequency and psychosocial aspects in psychogenic nonepileptic seizures (PNES). Although randomized controlled trials (RCTs) on different psychotherapies have been conducted for almost two decades now, no review has exclusively assessed RCTs of different psychotherapies. Methods: The objective was to review RCTs of psychotherapy for PNES, to understand the impact of different psychotherapies. Eligibility criteria included full-text articles, English articles, published between years 2000 and 2020, randomized trials of psychotherapy, and the adult population. Databases included PubMed, ProQuest, Google Scholar, ScienceDirect, EBSCO, PsycINFO, Cochrane, and a random google search was conducted. Rayyan software was used to include articles that met our eligibility criteria. The search was carried out independently by two researchers Results: Based on the eligibility criteria, seven studies were found. Amongst them, cognitive behavioral therapy (CBT) was the most researched and seemed more effective when paired with standard medical care (SMC) or sertraline. Comparisons of CBT and brief psychodynamic therapy did not reveal significant differences. Other psychotherapies included motivational interview+psychotherapy, which significantly reduced seizure frequency and improved psychosocial functioning. Paradoxical intention therapy also reduced PNES symptoms; however, it has not been researched in the last 15 years. Group psychoeducation seems to have an impact only on psychosocial functioning and not on seizure frequency. Conclusion: CBT paired with SMC or sertraline and MI along with psychotherapy yields the most effective results for PNES in reducing seizure frequency and improving psychosocial functioning. 2021 Indian Psychiatric Society - South Zonal Branch. -
Randomized response model to alter the nuisance effect of non-response due to stigmatized issues in survey sampling
The present study deals with the estimation procedures of the mean number of persons bearing a rare sensitive attribute in the clustered population under two-stage sampling scheme. The resultant estimators have been suggested using two-stage randomized response model when a rare unrelated attribute is assumed to be known as well as unknown. The properties of resultant estimators are studied where the first-stage samples are drawn using the probability proportional to the size with replacement sampling scheme. The estimation procedures have been further extended for the stratified clustered population. The empirical studies are performed for the validation of the suggested estimation procedures. Recommendations have been made to survey practitioners for their real-life applications. 2020 Informa UK Limited, trading as Taylor & Francis Group. -
Random forest application on cognitive level classification of E-learning content
The e-learning is the primary method of learning for most learners after the regular academics studies. The knowledge delivery through E-learning technologies increased exponentially over the years because of the advancement in internet and e-learning technologies. Knowledge delivery to some people would never have been possible without the e-learning technologies. Most of the working professional do focused studies for carrier advancement, promotion or to improve the domain knowledge. These learner can find many free e-learning web sites from the internet easily in the domain of interest. However it is quite difficult to find the best e-learning content suitable for their learning based on their domain knowledge level. User spent most of the time figuring out the right content from a plethora of available content and end up learning nothing. An intelligent framework using machine learning algorithms with random forest Classifier is proposed to address this issue, which classifies the e-learning content based on its difficulty levels and provide the learner the best content suitable based on the knowledge level. The frame work is trained with the data set collected from multiple popular e-learning web sites. The model is tested with real time e-learning web sites links and found that the e-contents in the web sites are recommended to the user based on its difficulty levels as beginner level, intermediate level and advanced level. Copyright 2020 Institute of Advanced Engineering and Science. All rights reserved. -
Ramifications of Climate Change Induced by Anthropogenic Factors on Global Fish Population Scenario
One of the important consequences of climate change is its effect on the global fish population. Though not very highly pronounced each year, the effect of climate change is of cumulative nature. Global aquaculture is being affected by temperature changes of both water and air. Fluctuations in the ocean surface temperatures, ocean current patterns, wind speeds, and wave directions, all have its impact on aquaculture. Each year we see more and more incidences of extreme weather conditions in different parts of the world, be it in the form of hurricanes, heavy floods, etc. Fishes are subjected to various stress factors which in turn take a toll on its growth and development. This can lead to lower weight gain and increased mortality due to higher susceptibility to diseases. This, coupled with direct unsustainable anthropogenic activities in the oceans and rivers may lead to collapse of the marine and freshwater ecosystem. Recent studies have identified specific regions where marine aquaculture production will be positively and negatively affected. One of the sustainable ways of developing aquaculture in the coming decades would be by developing region-wise strategies to maintain or increase fish population levels and thus meet the global seafood demands even in 2050. The current review is an attempt to assess the effects of ocean warming, ocean acidification, and ocean deoxygenation on the growth, survival, and diversity of marine lifeforms and suggest ways to stop a complete collapse of marine fish population by 2050, the year for which the complete collapse is predicted based on projections. The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2022. -
Raman spectrum of graphite layers in Indian coal
Two Indian coals of different rank (bituminous and subbituminous coal) have been demineralized by chemical method. Fourier transform Raman spectroscopy studies have been performed to study the changes in functional groups. Well resolved G peak is observed at 1605 cm-1 and 1590 cm-1 both in bituminous coal and subbituminous coal. With HF leaching, this doublet is reduced to a singlet along with reduction of frequency to 1585 cm -1 in subbituminous coal, where as in bituminous coal the absorption become very distinct. Bituminous coal is showing more intense absorption with HF leaching in this region where as subbituminous coal is shown a reduction in intensity. G' band is observed at ? 2700 cm-1 with almost the same intensity as that of G band. This confirms the presence of multilayer formation of graphite layer. The defect band at 1355 cm-1 is due to benzene or condensed benzene rings present in amorphous carbon. This band is weak in the present study. This is mainly due to immature nature of subbituminous coal than the higher rank bituminous coal. Graphite structure is remained behind after chemical leaching liberated oxygenated functional groups and mineral groups. The decrease of ID/IG ratio indicates that graphitization is increased in bituminous coal. 2011 American Institute of Physics. -
Raman spectroscopy investigation of camphor Soot: Spectral analysis and structural information
Raman spectra of camphor soot has been investigated and optimised with a Raman microscope system operated at laser excitation wavelength of 514.5 nm. Several band combinations for spectral analysis have been tested, and a combination of three Lorentian bands ( G,D1,D2) at about 1580, 1350 and 1620 cm-1, respectively, with Gaussian-shaped band (D3) at 1500 cm-1and 1200 cm-1 (D4) was best suited for the first order spectra. The second-order spectra were best fitted with Lorentian shaped bands at about 2450, 2700, 2900 and 3250 cm-1. The results are discussed and compared with X-ray diifraction measurements and SEM analysis. The camphor soot shows ? and P{cyrillic} bands which reveals the presence of crystalline graphitic carbon. The SEM micrographs of camphor show the presence of carbon nanostructures. 2013 by ESG. -
Rainbow neighbourhood number of graphs
In this paper, we introduce the notion of the rainbow neighbourhood and a related graph parameter namely the rainbow neighbourhood number and report on preliminary results thereof. 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 of a graph is called a rainbow neighbourhood. The number of rainbow neighbourhoods in a graph G is called the rainbow neighbourhood number of G, denoted by r?(G). We also introduce the concepts of an expanded line graph of a graph G and a v-clique of v ? V (G). With the help of these new concepts, we also establish a necessary and sufficient condition for the existence of a rainbow neighbourhood in the line graph of a graph G. 2019 Johan Kokand Sudev Naduvath and Muhammad Kamran Jamil. -
Rainbow degree-jump coloring of graphs
In this paper, we introduce a new notion called the rainbow degree-jump coloring of a graph. For a vertex v ? V(G), let the degree-jump closed neighbourhood of this vertex be defined as Ndeg [v] = {u: d(v, u) ? d(v)}. A proper coloring of a graph G is said to be a rainbow degree-jump coloring of G if for all v in V(G), c(Ndeg [v]) contains at least one of each color class. We determine a necessary and sufficient condition for a graph G to permit a rainbow degree-jump coloring. We also determine the rainbow degree-jump chromatic number, denoted by ?rdj (G), for certain classes of cycle related graphs. Mphako-Banda E.G., Kok J., Naduvath S., 2021. -
RAINBOW CHROMATIC TOPOLOGICAL INDICES OF CENTRAL GRAPHS OF SOME GRAPHS
The chromatic topological indices concept was introduced recently. Many other variations concerning the chromatic topological indices have been studied lately. In this paper, we have calculated the first and second rainbow chromatic Zagreb indices and rainbow chromatic irregularity indices for central graph of some standard graph classes. Palestine Polytechnic University-PPU 2024. -
Rain of Life, Rain of Music: Music as Life Power in Indian Thought and Contemporary Musical Traditions
Conceived as a life force, rain has a significant place in Indian thought. Sanskrit and vernacular literary and religious texts, as well as visual arts, emphasise its auspiciousness and importance in human life. Additionally, through the use of poetical images and metaphors, these texts and images associate rain with music and identify thunder with drums. Through the analysis of compositions from the repertoire of different drums such as the dhrupad pakh?vaj, the mi??vu of K?tiy???a? Sanskrit theatre, and the ritual music of Brahmanical temples of Kerala, this article studies the association of drumming with rain as a symbol of life force, consciousness and enlightenment. 2022 South Asian Studies Association of Australia. -
Radon transform processed neural network for lung X-ray image based diagnosis
A novel method for image diagnosis with artificial learning is presented-ray images tuberculosis patients is subjected to neural network learning for prediction of diagnosis. The X-ray images of lungs are normally difficult for diagnosis, since its similarity to lung cancer. Under and over diagnosis of lung X-ray images is a difficult medical problem to resolve. In the present work radon transform of the x-ray images is fed to back propagation neural network trained with Levenberg algorithm. The present methodology gives sharp results, distincting the normal and abnormal images. 2014 IEEE. -
Radon transform based image steganography in frequency domain /
International journal Of Applied Engineering Research, Vol.10, Issue 70, pp.830-834, ISSN No: 0973-4562.