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51.
Surabhi Verma Som Sekhar Bhattacharyya Saurav Kumar 《Information processing & management》2018,54(5):791-806
Research on the adoption of systems for big data analytics has drawn enormous attention in Information Systems research. This study extends big data analytics adoption research by examining the effects of system characteristics on the attitude of managers towards the usage of big data analytics systems. A research model has been proposed in this study based on an extensive review of literature pertaining to the Technology Acceptance Model, with further validation by a survey of 150 big data analytics users. Results of this survey confirm that characteristics of the big data analytics system have significant direct and indirect effects on belief in the benefits of big data analytics systems and perceived usefulness, attitude and adoption. Moreover, there are mediation effects that exist among the system characteristics, benefits of big data analytics systems, perceived usefulness and the attitude towards using big data analytics system. This study expands the existing body of knowledge on the adoption of big data analytics systems, and benefits big data analytics providers and vendors while helping in the formulation of their business models. 相似文献
52.
Yogesh M. Patel Sanidhya Jain Abhishek Kumar Singh Kedar Khare Sarita Ahlawat Supreet Singh Bahga 《Biomicrofluidics》2020,14(6)
We present design, characterization, and testing of an inexpensive, sheath-flow based microfluidic device for three-dimensional (3D) hydrodynamic focusing of cells in imaging flow cytometry. In contrast to other 3D sheathing devices, our device hydrodynamically focuses the cells in a single-file near the bottom wall of the microchannel that allows imaging cells with high magnification and low working distance objectives, without the need for small device dimensions. The relatively large dimensions of the microchannels enable easy fabrication using less-precise fabrication techniques, and the simplicity of the device design avoids the need for tedious alignment of various layers. We have characterized the performance of the device with 3D numerical simulations and validated these simulations with experiments of hydrodynamic focusing of a fluorescently dyed sample fluid. The simulations show that the width and the height of the 3D focused sample stream can be controlled independently by varying the heights of main and side channels of the device, and the flow rates of sample and sheath fluids. Based on simulations, we also provide useful guidelines for choosing the device dimensions and flow rates for focusing cells of a particular size. Thereafter, we demonstrate the applicability of our device for imaging a large number of RBCs using brightfield microscopy. We also discuss the choice of the region of interest and camera frame rate so as to image each cell individually in our device. The design of our microfluidic device makes it equally applicable for imaging cells of different sizes using various other imaging techniques such as phase-contrast and fluorescence microscopy. 相似文献
53.
54.
选用课堂互动双编码分析系统(MFIAS),运用矩阵分析和曲线分析等方式,从课堂氛围、教师提问倾向、课堂结构、教学风格等方面对"一师一优课"中的某一堂高中数学优质课教学视频进行分析.研究表明:该数学课堂气氛融洽,师生互动频繁;教学方式多样化,教师充分尊重学生的主体地位,主要采用"小步走"的教学模式.这启示我们:为了提升师生课堂互动行为效率,教师要加强信息技术与数学课程的融合,营造融洽的课堂氛围,构建课堂教学共同体;让问题驱动学习,提高学生的问题解决能力;合理安排课堂小结,梳理数学知识脉络. 相似文献
55.
Solitons emerge as non-perturbative solutions of non-linear wave equations in classical and quantum theories. These are non-dispersive
and localised packets of energy — remarkable properties for solutions of non-linear differential equations. In the presence
of such objects, the solutions of Dirac equation lead to the curious phenomenon of ‘fractional fermion number’. Under normal
conditions the fermion number takes strictly integral values. In this article, we describe this accidental discovery and its
manifestation in polyacetylene chains, which has led to the development of organic conductors.
(left) Kumar Rao is a Postdoctoral Fellow at PRL, Ahmedabad. He is interested in particle physics phenomenology as probed
in particle colliders and formal aspects of quantum field theory.
(right) Narendra Sahu is currently a postdoctoral fellow at Lancaster University, UK. His main research area includes Cosmology
and Astroparticle physics. Currently he is working on dark matter and matter anti-matter asymmetry of the universe.
(center) P K Panigrahi’s research interests are in the area of quantum computation, solitons in Bose Einstein condensates
& nonlinear optical media. He is also deeply interested in science education and derives pleasure from long weekend walks. 相似文献
56.
57.
Shubham Goel Ravinder Kumar Munish Kumar Vikram Chopra 《Information processing & management》2019,56(3):1053-1066
In the whole world, the internet is exercised by millions of people every day for information retrieval. Even for a small to smaller task like fixing a fan, to cook food or even to iron clothes persons opt to search the web. To fulfill the information needs of people, there are billions of web pages, each having a different degree of relevance to the topic of interest (TOI), scattered throughout the web but this huge size makes manual information retrieval impossible. The page ranking algorithm is an integral part of search engines as it arranges web pages associated with a queried TOI in order of their relevance level. It, therefore, plays an important role in regulating the search quality and user experience for information retrieval. PageRank, HITS, and SALSA are well-known page ranking algorithm based on link structure analysis of a seed set, but ranking given by them has not yet been efficient. In this paper, we propose a variant of SALSA to give sNorm(p) for the efficient ranking of web pages. Our approach relies on a p-Norm from Vector Norm family in a novel way for the ranking of web pages as Vector Norms can reduce the impact of low authority weight in hub weight calculation in an efficient way. Our study, then compares the rankings given by PageRank, HITS, SALSA, and sNorm(p) to the same pages in the same query. The effectiveness of the proposed approach over state of the art methods has been shown using performance measurement technique, Mean Reciprocal Rank (MRR), Precision, Mean Average Precision (MAP), Discounted Cumulative Gain (DCG) and Normalized DCG (NDCG). The experimentation is performed on a dataset acquired after pre-processing of the results collected from initial few pages retrieved for a query by the Google search engine. Based on the type and amount of in-hand domain expertise 30 queries are designed. The extensive evaluation and result analysis are performed using MRR, [email protected], MAP, DCG, and NDCG as the performance measuring statistical metrics. Furthermore, results are statistically verified using a significance test. Findings show that our approach outperforms state of the art methods by attaining 0.8666 as MRR value, 0.7957 as MAP value. Thus contributing to the improvement in the ranking of web pages more efficiently as compared to its counterparts. 相似文献
58.
Sonika Gupta Niraj Shende Swati Banerjee Satish Kumar M. V. R. Reddy Bhaskar C. Harinath 《Indian journal of clinical biochemistry : IJCB》2002,17(1):5-8
Tuberculosis remains major health problem in India and developing countries Immunodiagnosis has important role in screening,
diagnosis and management of tuberculosis. SEVA TB ES-31 antigen has shown potential in detecting tuberculous IgG antibody
in earlier studies from our laboratory. In the present study we have analysedSEVA TB ES-31 antigen specific immunoglobulinsIgM, IgA and IgG in clinically and bacteriologically confirmed pulmonary tuberculosis cases to determine the usefulness of specific immunoglobulin
class in the diagnosis of patients attending the hospital.
Of the 30 cases of pulmonary tuberculosis 25 (83.3%) were positive for IgG, 19 (63.3%) for IgM and 16 (53.3%) for IgA. On
combining IgG and IgM positivity, sensitivity was increased to 93.3%. While combining IgG and IgA positivity, sensitivity
increased to 90%. However specificity was decreased to 66.6% and 70% for both of these combinations respectively. It could
be envisaged from this study that IgG antibody detection against ES-31 antigen showed acceptable sensitivity (83.3%) and specificity
(86.6%) compared to IgM or IgA alone or in combination. When immune responses were analysed according to degree of sputum
positivity, IgG response was observed to be predominant in all grades, compared to IgM or IgA antibody. The addition of IgM
or IgA as an adjunct test increases the sensitivity but at the cost of specificity. Hence the detection of IgG alone is more
useful compared to IgM or IgA assay, in detecting tuberculosis disease cases coming to the hospital. 相似文献
59.
60.
This article presents a new approach to modeling information flows within today's information systems environments characterized by electronic commerce. We treat information as a resource whose value is fundamentally multidimensional in nature. In this article we consider the economic and psychological dimensions of the value of information. It is argued that it is meaningless to model the value of information in isolation away from the context and the specific parties between which this information is exchanged. We therefore focus exclusively on modeling information flows rather than information itself. To achieve this, we propose a formal framework for describing transactions involving information flows. The framework consists of a generalized model for representing information transactions and for defining a set of fundamental properties of multiparty transactions. These properties are fairness, constructiveness, and monopoly. Where applicable, they are defined for individuals, transactions, and a system of transactions. The proposed model reveals the nature of individual transactions and markets, and consequently has important implications for simulation of market scenarios and to help arrive at effective policies for pricing and market regulations. 相似文献