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981.
B. Krishna Kumar G. Vijayalakshmi A. Krishnamoorthy S. Sadiq Basha 《Computers & Operations Research》2010,37(7):1247-1255
A Markovian single server feedback retrial queue with linear retrial rate and collisions of customers is studied. Using generating function technique, the joint distribution of the server state and the orbit length under steady-state is investigated. Some interesting and important performance measures of the system are obtained. Finally, numerical illustrations are provided. 相似文献
982.
983.
Ravi Seethamraju Krishna Sundar Diatha Shashank Garg 《Information Systems Frontiers》2018,20(1):163-181
There are 2.2 million cases of tuberculosis (TB) in India, with an economic burden of $3 billion per year. Efficient monitoring of TB treatment is critical and the Indian Government’s current reliance on a pen and paper system for monitoring patients’ adherence to treatment is neither effective nor scalable. Employing the unified theory of acceptance and use of technology model (UTAUT) as its theoretical foundation, this study investigates the factors influencing the acceptance and use of a mobile-based IT solution for TB treatment monitoring. Data was collected from a survey of healthcare professionals working in TB treatment clinics and analysed using partial least squares structural equation modelling. Four constructs in the UTAUT model, effort expectancy (EE), facilitating conditions (FC), performance expectancy (PE) and social influence (SI) – were found to significantly and positively influence healthcare professionals’ behavioral intention to use the proposed mobile-based IT solution, and explained 56% of the variance. Importantly, our study validates the predictive capabilities of the UTAUT model in public health service delivery context in a developing country. 相似文献
984.
A. Guruvareddy K. Sri Rama Krishna M. N. Giri Prasad 《Pattern Recognition and Image Analysis》2011,21(4):606-615
Nowadays, Image enhancement finds enormous image processing applications, which are related to practical situations, Contrast
enhancement is one among the different image enhancement techniques that intends to improve the image visibility. Though several
works for local contrast enhancement are available in the literature, the effectiveness remains an issue and the enhancement
performance needs to be improved. In this paper, a local contrast enhancement technique is proposed for both gray scale images
and RGB color images. The proposed technique is comprised of two stages of enhancement, namely, local statistics-based image
enhancement and Genetic Algorithm based local contrast enhancement. The former stage is a pre-enhancement stage and the later
is the major stage of enhancement. In the former stage, the image is processed in window basis and the local statistics of
the image is obtained. Based on the local statistics, the image is enhanced. In the later stage, the window based operation
is performed over the preenhanced image and the local contrast is enhanced. The Genetic Algorithm aids in searching of an
optimal contrast factor, which plays vital role in the contrast enhancement. The technique is evaluated with both gray scale
images as well as RGB color images and performance is compared with the existing contrast enhancement techniques. 相似文献
985.
Krishna Sapkota Arantza Aldea Muhammad Younas David A. Duce Rene Banares-Alcantara 《Service Oriented Computing and Applications》2016,10(4):365-389
The mapping of regulatory guidelines with organizational processes is an important aspect of a regulatory-compliance management system. Automating this mapping process can greatly improve the overall compliance process. Currently, there is research on mapping between different entities such as ontology mapping, sentence similarity, semantic similarity and regulation-requirement mapping. However, there has not been adequate research on the automation of the mapping process between regulatory guidelines and organizational processes. In this paper, we explain how Natural Language Processing and Semantic Web technologies can be applied in this area. In particular, we explain how we can take advantage of the structures of regulation-ontology and the process-ontology in order to compute the similarity between a regulatory guideline and a process. Our methodology is validated using a case study in the Pharmaceutical industry, which has shown promising results. 相似文献
986.
Sharma P Singh P Bisetty K Corcho FJ Perez JJ 《Journal of molecular graphics & modelling》2010,29(4):581-590
The present work involves the study of the conformational profile of bombesin using different computational procedures used to explore the configurational space based on molecular dynamics simulations. Specifically, the present study describes the effect of using Berendsen's versus Langevin's thermostat and on the other hand, the use of the multicanonical replica exchange molecular dynamics as compared to standard molecular dynamics. In these simulations the solvent was modeled using the Onufriev, Bashford and Case implementation of Generalized Born procedure. The detailed computational analysis agrees well with the aggregated information previously reported in the NMR study of the peptide in a mixture of trifluoroethanol/water. Present results show a clear preference for the peptide to attain a helical structure on the segment 6-14, with a tendency to adopt a α-helix at the C-terminus aligning the aromatic residues Trp8 and His12 together with Gln7, known to be important for peptide mediated activation. Finally, the three methodologies used in the present work yield similar structural results, although a detailed analysis reveals biases that need to be considered when performing this kind of studies. 相似文献
987.
A design of compact, sharp rejection microstrip lowpass filters (LPF) with wide‐stopband is presented by using signal interference technique. The filter parameters can be easily controlled by the characteristic impedances of the configuration. Explicit design equations with graphs are presented. To validate the theoretical prediction, two prototype LPFs are fabricated. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010. 相似文献
988.
Milliseconds microfluidic chaotic bubble mixer 总被引:2,自引:2,他引:0
Xiaole Mao Bala Krishna Juluri Michael Ian Lapsley Zackary Stoeri Stratton Tony Jun Huang 《Microfluidics and nanofluidics》2010,8(1):139-144
In this study, we report a rapid microfluidic mixing device based on chaotic advection induced by microbubble–fluid interactions.
The device includes inlets for to-be-mixed fluids and nitrogen gas. A side-by-side laminar flow segmented by monodisperse
microbubbles is generated when the fluids and the nitrogen are co-injected through a flow focusing micro-orifice. The flow
subsequently enters a series of hexagonal expansion chambers, in which the hydrodynamic interaction among the microbubbles
results in the stretch and fold of segmented fluid volumes and rapid mixing and homogenization. We characterize the performance
of the microfluidic mixer and demonstrate rapid mixing within 20 ms. We further show that bubbles can be conveniently removed
from the mixed fluids using a microfluidic comb structure on completion of the mixing. 相似文献
989.
The various contributions to the flow stress at room temperature of a cast Co-Cr-Mo-C alloy were identified using transmission electron microscopy. These alloys are used as surgical implant materials. It was concluded that stacking fault intersections and twins make the largest contribution to the work hardening behaviour of the as-cast Co-Cr-Mo-C alloy. The stacking fault intersection was modelled as a form of dislocation dipole, from which the stress interaction with slip dislocations was estimated. In the case of twin-slip interactions, it is suggested that the incorporation of the slip dislocation into the twin is governed by the reaction 1/2[110](¯11¯1)1/6[141](¯1¯15)+1/6[2¯1¯1]coherent Twin Boundary (111) A nucleation model for twinning in alloys with very low stacking fault energy is also proposed. 相似文献
990.
Tollamadugu N.V.K.V. Prasad Shaik Adam Pasupuleti Visweswara Rao Balam Ravindra Reddy Thimmavajjula Giridhara Krishna 《IET nanobiotechnology / IET》2017,11(3):277
Advancement in materials synthesis largely depends up on their diverse applications and commercialisation. Antifungal effects of phytogenic silver nanoparticles (AgNPs) were evident, but the reports on the effects of the same on agricultural crops are scant. Herein, we report for the first time, size dependent effects of phytogenic AgNPs (synthesised using Stevia rebaudiana leaf extract) on the germination, growth and biochemical parameters of three important agricultural crops viz., rice (Oryza sativa L), maize (Zea mays L) and peanut (Arachis hypogaea L). AgNPs with varied sizes were prepared by changing the concentration and quantity of the Stevia rebaudiana leaf extract. As prepared AgNPs were characterized using the techniques, such as high‐resolution transmission electron microscopy, particle size and zeta potential analyser. The measured (dynamic light scattering technique) average sizes of particles are ranging from 68.5 to 116 nm. Fourier transform infrared studies confirmed the participation of alcohols, aldehydes and amides in the reduction and stabilisation of the AgNPs. Application of these AgNPs to three agricultural crop seeds (rice, maize and peanut) resulted in size dependent effects on their germination, growth and biochemical parameters such as, chlorophyll content, carotenoid and protein content. Further, antifungal activity of AgNPs also evaluated against fungi, Aspergillus niger.Inspec keywords: antibacterial activity, silver, nanoparticles, nanomedicine, biochemistry, crops, transmission electron microscopy, Fourier transform infrared spectra, electrokinetic effects, organic compounds, particle size, plant diseases, microorganismsOther keywords: fungi, Aspergillus niger, size 68.5 nm to 116 nm, silver particles, phytoextract, amide functional groups, aldehydes, alcohols, Fourier transform infrared studies, zeta potential analyser, particle size, high‐resolution transmission electron microscopy, Stevia plant leaf extract, agricultural crops, antifungal effects, materials synthesis, Arachis hypogaea L, peanut, Zea mays L, maize, Oryza sativa L, rice, biochemical parameters, growth, germination, antifungal phytogenic silver nanoparticles, size dependent effects 相似文献