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1.
Surabhi Potnis 《Resonance》2017,22(3):257-268
This article aims to highlight the amazing properties and potential uses of the more recently developed allotropes of carbon such as carbon nanotubes, graphene, fullerene, and buckypaper. This is an area offering wide opportunity for research, especially due to the multidisciplinary nature of applications. 相似文献
2.
Devendra Potnis Kanchan Deosthali Xiaohua Zhu Rebecca McCusker 《Library & information science research》2018,40(2):106-117
Academic libraries invest millions of dollars to make electronic resources such as e-books available to students for free. However, free access might not necessarily result in students' sustained interest in and use of e-books. This interdisciplinary, mixed methods research investigates the factors influencing the intention of 279 undergraduate students to use e-books at a land-grant university in the southern US. Structural equation modeling of the survey responses suggests that organizational environment for information technology, external locus of control, subjective norm, perceived enjoyment (i.e., joyfulness), and information technology features play a significant role in influencing the intention of students to use e-books. Based on a combination of quantitative results and qualitative findings, this study identifies eight activities that libraries need to undertake in order to increase the use of e-books by undergraduate students. 相似文献
3.
A method is advanced for the design of linear controllers for a class of nonlinear systems. The systems considered in this paper are characterized by the presence of a dominant nonlinearity located in a specified sector. The proposed approach is digital-computer oriented, and design results are presented in parameter planes and parameter space. 相似文献
4.
Devendra Sahal 《Research Policy》1985,14(2):61-82
This paper presents an integrative view of innovation processes based on a theory of systems developed by the author over the past few years. In its essence, one of the most important clues to the origin of innovations is to be found in the fact that the performance of every technology depends upon its size and structure. Specifically, as a technology is continuously made to become larger or smaller, the relationship between its size and structural requirements changes, which in turn, severely limits the scope of its further evolution. Thus the origin of a wide variety of innovations lies in learning to overcome the constraints that arise from the process of scaling the technology under consideration. In short, technical progress is best characterized as a process of learning by scaling.These considerations in turn point to a trilogy of innovations corresponding to three main types of technological constraints: structural innovations that arise from a process of differential growth whereby the parts and the whole of a system do not grow at the same rate: material innovations involving a change in the construction stuff; and systems innovations that arise from the integration of two or more symbiotic technologies in an attempt to simplify the outline of the overall structure. The proposed trilogy is shown to account for the emergence of various techniques including the so-called revolutionary innovations in a variety of fields.The theory is developed and illustrated through three case studies of technical progress in the aircraft, farm tractor, and computer industries. The results of our investigation further reveal that the process of innovation is best conceived in terms of a certain topography of technological evolution. Specifically, we find that technical progress is invariably characterized by the existence of what may be called technological guideposts and innovation avenues that lay out certain definite paths of development. Chance determines which amongst many technological guideposts will be chosen in the course of development. Once the development is well along a certain innovation avenue. necessity prevails until another point connecting other technological guideposts and innovation avenues is reached. This brings chance back to the fore and the process continues. In sum, the process of technological evolution is determined by the interplay of chance and necessity rather than one at the exclusion of the other. 相似文献
5.
Devendra K. Rai Prashant Kumar Rai Aradhna Gupta Geeta Watal Bechan Sharma 《Indian journal of clinical biochemistry : IJCB》2009,24(2):198-201
Wistar rats of 6–8 weeks in age weighing between 120–150 g were exposed to the fixed doses of each of the carbamate pesticides
such as cartap (50% LD50) and carbofuran (50% LD50) as well as a combination of these two with 25% LD50 of each for one week. The effect of treatments was studied in terms of serum lipid parameters such as high-density lipoprotein,
total cholesterol, triglyceride, low-density lipoprotein and very low-density lipoprotein. Treatment with individual doses
of carbofuran (50% LD50) and cartap (50 % LD50) caused significant alterations in the levels of serum lipid parameters. The pesticides treatment resulted in marked decrease
in the level of serum high-density lipoprotein where as that of other lipids got significantly elevated. Further, the rats
exhibited relatively higher impact of pesticides when treated with the compounds in combination (25 % LD50 of each). The results indicated that these compounds when used together may exert enhanced effect on the levels of serum
lipids in rat. 相似文献
6.
We present experimental and simulation results for focused ion beam (FIB) milling of microchannels in lithium niobate in this paper. We investigate two different cuts of lithium niobate, Y- and Z-cuts, and observe that the experimental material removal rate in the FIB for both Y-cut and Z-cut samples was 0.3 μm3/nC, roughly two times greater than the material removal rate previously reported in the literature but in good agreement with the value we obtain from stopping and range of ions in matter (SRIM) simulations. Further, we investigate the FIB milling rate and resultant cross-sectional profile of microchannels at various ion beam currents and find that the milling rate decreases as a function of ion dose and correspondingly, the cross-sectional profiles change from rectangular to V-shaped. This indicates that material redeposition plays an important role at high ion dose or equivalently, high aspect ratio. We find that the experimental material removal rate decreases as a function of aspect ratio of the milled structures, in good agreement with our simulation results at low aspect ratio and in good agreement with the material removal rates previously reported in the literature at high aspect ratios. Our results show that it is indeed easier than previously assumed to fabricate nanochannels with low aspect ratio directly on lithium niobate using the FIB milling technique. 相似文献
7.
Devendra Dilip Potnis 《The Information Society》2013,29(1):83-93
Digital inclusion research has focused overwhelmingly on access to information. But access to information by itself is of limited value unless the intended beneficiary has the capacity to use it. It is the use of information that delivers the benefits. However, in information and communication technologies for development literature, there is little empirical work on the process by which use of information delivers benefits. This study fills the gap by studying information use by poor female mobile phone users in rural India. It identifies six stages in the information use process and models them. 相似文献
8.
Since 2001, the United Nations (UN) and affiliated organizations have measured e-Government initiatives of more than 178 Member States of the UN, by devising “e-Government Readiness Index” (e-GRI) and “e-Participation Index” (e-PI). The UN has published rankings for its Member States in terms of e-GRI and e-PI, through e-Government Readiness Assessments (Surveys). Member States of the UN and digital government research community as well as academicians and practitioners regularly use the e-GRI and e-PI as a point-of-reference; this fact alone signifies the importance of evaluating the existing UN methodologies assessing e-Governance. Since e-Governance is one of the greatest innovations in the public sector, this research uses conceptual content analysis on the Surveys using the Innovation Management Measurement Framework (IMMF), which is one of the most widely accepted theoretical frameworks for measuring innovation initiatives. The resultant percentage normalized scores (PNS) lead to a set of recommendations for developing better informed, more balanced, and more powerful e-GRI and e-PI for the future. 相似文献
9.
Devendra Sahal 《Research Policy》1981,10(4):368-402
While the of diffusion of technology has been extensively studied, a sysetematic treatment of origin of innovations is generally lacking. This has important implications for studies not only of the phenomenon of diffusion itself, but also for studies of long-term growth of productivity. This paper presents an investigation of technological; innovations in the farm tractor during a time period of nearly five decades from its genesis. It is concluded that the observed advances in technology are attributable to variations in farm size and experience acquired in the production and utilization of the tractor over the course of time. More generally, two main hypotheses of technological change emerge from the results of thus study. One is the hypothesis of learning i.e. that technological innovation originates in the accumulated experience of a practical nature. The other is the hypothesis of scaling, i.e. that the process of innovation is further governed by changes in the size of the larger system, within which the technology is embedded. However, certain widely believed alternative hypotheses of technological change do not seem to generally hold. It is concluded that technological development is an evolutionary process which is best understood in terms of an internal logic of its own. 相似文献
10.