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21.
22.
Delayed settling of the ash particles and poor drainage of water from the pond ash are the major problems faced during the hydraulic stowing of pond ash. In this study the effect of polymeric flocculant on settling of the ash particles and drainage of water during pond ash stowing are investigated. In addition, the parameters, viz. drainage and absorption of water during pond ash stowing are quantified by stowing a mine goaf model with pond ash slurries of five different concentrations added with and without flocculant. The study revealed that addition of only 5 × 10?6 of Sodium Carboxymethyl Cellulose (Na-CMC) flocculant with the pond ash slurries during stowing offers best result in terms of quicker settling of the ash particles and enhanced water drainage from the hydraulically stowed pond ash. Besides, it resulted in drainage of more than 85% of the total water used in the initial 45 min of stowing. The improvement in drainage is caused due to coagulation and flocculation of the pond ash particles because of charge neutralization and particle–particle bridging. This study may provide a basis for estimating the drainage and absorption of water during the real pond ash stowing operation in underground mines. 相似文献
23.
This paper presents a robust fuzzy c-means (FCM) for an automatic effective segmentation of breast and brain magnetic resonance images (MRI). This paper obtains novel objective functions for proposed robust fuzzy c-means by replacing original Euclidean distance with properties of kernel function on feature space and using Tsallis entropy. By minimizing the proposed effective objective functions, this paper gets membership partition matrices and equations for successive prototypes. In order to reduce the computational complexity and running time, center initialization algorithm is introduced for initializing the initial cluster center. The initial experimental works have done on synthetic image and benchmark dataset to investigate the effectiveness of proposed, and then the proposed method has been implemented to differentiate the different region of real breast and brain magnetic resonance images. In order to identify the validity of proposed fuzzy c-means methods, segmentation accuracy is computed by using silhouette method. The experimental results show that the proposed method is more capable in segmentation of medical images than existed methods. 相似文献
24.
As we live in a culture where “everything can be commodified, measured and calculated and can be put in the competitive market for sale, detached from its roots and purpose,” there is need to redefine our humanness in terms of the changing nature of science, technology, and their deeper impact on human life. More than anything else, it is Information Technology that now has tremendous influence on all spheres of our life, and in a sense, IT has become the destiny of our life. And this is where the real trauma lies. On the one hand, our being in the cyberspace opens up new and exciting horizons before us; on the other hand, we ourselves are changed and transformed in the process. The virtual world transforms human users to a problem-solver technocrat. The speed at which Information Technology is changing the way that youth around the world are socializing, playing, and researching, it is the common practice now for a 15-year old to go home and update their MySpace page, followed by playing online games, or looking up the new trendy YouTube video. These forms of technology are often the topic of adolescent conversations as YouTube, blogs, e-magazines, Face book, MySpace, iPhones, and iPods dominate the commercial and social networking market. Some researchers refer to this phenomenon as ubiquitous technology drawing attention to the fact that ubiquitous technology acknowledges the speedy adoption of day-to-day use of technology as a global phenomenon. In this background, this article aims at revisiting the question, “What is to be human in the era of Ubiquitous Technology?” From a feminist perspective, one can still redefine the boundaries between femininity and masculinity in the context of IT and its impact on our lifestyle and thought style. While examining the ways in which our definitions of “woman” and “man” are shifting in this new communication environment, Elizabeth Lane Lawley observes that we cannot fix a single center from which the experiences of women with computer and communication systems can be viewed and that such fixity would only serve to deepen inequities rather than exposing and removing them. She finally submits, “It is possible to use new theoretical perspectives on the shifting boundaries of gender definitions to rethink a previously deterministic view of the effect of new technologies on society, and particularly the effect of those technologies on women. While the gradual absence of the subject from the field of Artificial Intelligence leads to the invisibility of feminine care along with social and relational nature of man, some feminists dismiss the biological sex distinction on such issues and encourage females to ‘imitate man’ and to become more aggressive, assertive and dominating” (Lawley 1993). What are the possible impacts of this new technology on the so-called feminine traits of our human nature? How far our definitions of “woman” and “man” are shifting in this new communication environment? This is what this article seeks to explore. 相似文献
25.
Kumar DD Mitra S Senthil K Sharma DK Rajan RN Sharma A Nagesh KV Chakravarthy DP 《The Review of scientific instruments》2008,79(4):045104
A design approach giving the optimum number of stages in a magnetic pulse compression circuit and gain per stage is given. The limitation on the maximum gain per stage is discussed. The total system volume minimization is done by considering the energy storage capacitor volume and magnetic core volume at each stage. At the end of this paper, the design of a magnetic pulse compression based linear induction accelerator of 200 kV, 5 kA, and 100 ns with a repetition rate of 100 Hz is discussed with its experimental results. 相似文献
26.
Sandeep Peddi Rapur Ram Varalakshmi Devi Boreddy Sridhar Avssn Krishna Kishore Chennu Siva Kumar Vishnubotla 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(1):192-194
We present an end‐stage renal disease patient on dialysis with fever. The primary source was right internal jugular vein catheter which had metastatic infections in the body probably via an arteriovenous communication in a cavity in left lung. Patient had right psoas muscle abscess and a left kidney abscess. An 18F‐fluorodeoxyglucose‐positron emission spectroscopy scan was done to find out left kidney abscess. A search of literature did not reveal many patients of psoas abscess secondary to infection of hemodialysis access. 相似文献
27.
Nirupama Mallick Shovon Mandal Amit Kumar Singh Moumita Bishai Archana Dash 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(1):137-145
BACKGROUND: A major bottleneck in microalgal biodiesel production is lipid content, which is often low in microalgal species. The present study examines Chlorella vulgaris as a potential feedstock for biodiesel by identifying and evaluating the relationships between the critical variables that enhance the lipid yield, and characterizes the biodiesel produced for various properties. RESULTS: Factors affecting lipid accumulation in a green microalga, Chlorella vulgaris were examined. Multifactor optimization raised the lipid pool to 55% dry cell weight against 9% control. When C. vulgaris cells pre‐grown in glucose (0.7%)‐supplemented medium were transferred to the optimized condition at the second stage, the lipid yield was boosted to 1974 mg L?1, a value almost 20‐fold higher than for the control. The transesterified C. vulgaris oil showed the presence of ~82% saturated fatty acids, with palmitate and stearate as major components, thus highlighting the oxidative stability of C. vulgaris biodiesel. The fuel properties (density, viscosity, acid value, iodine value, calorific value, cetane index, ash and water contents) are comparable with the international (ASTM and EN) and Indian (IS) biodiesel standards. CONCLUSION: C. vulgaris biomass with 55% lipid content and adequate fuel properties is potentially a renewable feedstock for biodiesel. Copyright © 2011 Society of Chemical Industry 相似文献
28.
Surveys are mainly conducted to obtain valuable information on some criteria from a specified population. But, the survey results often become biased due to non-response of the subjects under study for highly significant attributes. Such non-ignorable missingness need to be treated and the actual values should be retrieved. Many methods have already been proposed for handling missing values in either discrete or continuous attributes. But, there exists a large gap in handling non-ignorable missing values in datasets with mixed attributes. With the intent of addressing this gap, this paper proposes a methodology called as Bayesian Genetic Algorithm (BAGEL) with hybridized Bayesian and Genetic Algorithm principles. In BAGEL, the initial population is generated using Bayesian model and fitness values of the chromosomes are evaluated using Bayesian principles. BAGEL is implemented in real datasets for imputing both discrete and continuous missing values and the imputation accuracy is observed. The experimental results show the superior performance of BAGEL than other standard imputation techniques. Statistical tests conducted to validate the experimental results also prove that BAGEL outperforms at all missing rates from 5% to 50%. 相似文献
29.
Bhupendra Singh Nitika Devi Lakshya Mathur Rajesh K. Singh Aman Bhardwaj Sun-Ju Song Dirk Henkensmeier 《Ceramics International》2018,44(6):6170-6175
In the present work, we report a method of fabrication of dense 10 mol% Mg2+-doped cerium pyrophosphate-phosphate (Ce0.9Mg0.1P2O7-PmOn; CMP-P) composites by microwave heat-treatment of the preformed Ce0.9Mg0.1P2O7 substrates in the presence of phosphoric acid. The composite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The microwave heating at 375 °C for 5 min resulted in the formation of dense CMP-P composites which retained most of the pyrophosphate phase. The electrical conductivity was extracted from the EIS data and for the CMP-P composite prepared by H3PO4 loading for 10 h and microwave heat-treatment for 5 min it was found to be >10?2 S m?1 in 100–250 °C range with a maximum of 0.062 S cm?1 at 190 °C, which was significant for its application as electrolyte in intermediate temperature fuel cells. 相似文献
30.
Ammani Kuttan Baby Sarpabhushana Manjunatha S. Jayanthi Bijjanal Jayappa Gireesha M. Archana 《亚洲传热研究》2021,50(1):279-291
Iron oxide nanoparticles have great importance in future biomedical applications because of their intrinsic properties, such as low toxicity, colloidal stability, and surface engineering capability. So, blood containing iron oxide nanoparticles are used in biomedical sciences as contrast agents following intravenous administration. The current problem deals with an analysis of the melting heat transfer of blood consisting iron nanoparticles in the existence of free convection. The principal equations of the problem are extremely nonlinear partial differential equations which transmute into a set of nonlinear ordinary differential equations by applying proper similarity transformations. The acquired similarity equalities are then solved numerically by Runge‐Kutta Felhsberg 45th‐order method. The results acquired are on the same level with past available results. Some noteworthy findings of the study are: the rate of heat transfer increases as the Casson parameter increases and also found that the temperature of the blood can be controlled by increasing or decreasing the Prandtl number. Hence, we conclude that flow and heat transfer of blood have significant clinical importance during the stages where the blood flow needs to be checked (surgery) and the heat transfer rate must be controlled (therapy). 相似文献