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1.
Neural Processing Letters - The uncertainty caused mainly by the deficiency of precision and data, artificial/human-made errors, information accessed from expert opinions or very miniature size of...  相似文献   
2.
The condition macromastia has not been defined and characterized precisely by the medical community. Whether the patient with hypertrophic breasts is a candidate for or can be helped by reduction mammaplasty is unclear to both the medical and the lay community. A prospective study of 39 women undergoing reduction mammaplasty surgery was initiated to answer these questions. Patients rated the severity of their somatic pain symptoms and discomfort before reduction mammaplasty and again after complete recovery. The severity of their symptoms and complaints was numerically graded and analyzed. These data were compared with similar data obtained from 40 "small-breasted" women of similar age. Headache, neck pain, back pain, shoulder pain, and bra strap groove pain were present in 60 to 92 percent of patients, and 97 percent of patients had at least three of these pain symptoms preoperatively. All the patients had reduction of their pain symptomatology postoperative, and 25 percent of the study patients had total elimination of pain symptoms by reduction mammaplasty. The postoperative incidence and severity of pain symptoms and discomfort complaints were statistically equivalent to or less than the levels in the control group.  相似文献   
3.
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   
4.
To understand the flow behavior of a newly developed austenitic stainless steel 316LN with 0.14 wt% nitrogen, isothermal compression tests have been carried out in the hot working domain. From the analysis of flow behavior, it is observed that the nitrogen enhanced steel, in its hot working domain exhibits strain and strain rate hardening with thermal softening. The flow behavior analysis also demonstrates the coupled effect of strain–temperature and strain rate temperature on the flow stress. To depict the flow behavior of the material, strain compensated Arrhenius (SCA) equation and Model D8A have been used. The SCA predicts the flow curves with an average absolute error of 9.27% and a correlation coefficient of 0.977, whereas the prediction by Model D8A gives the average absolute relative error as 10.86% with a correlation coefficient of 0.966. For high temperature and intermediate strain rate, both Model D8A and SCA equation depict the flow behavior of 316L (0.14)N SS with good correlation and generalization. However, at low temperature and high strain rate domain, both the models are unable to depict the behavior; this is attributed to the fact that the material shows two slope behaviors where the constants have been calculated assuming a linear relationship between stress and strain rate.  相似文献   
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6.
Blends of linear low density polyethylene (LLDPE) and ethylene-co-methyl acrylate (EMA) having 60/40 composition was studied with and without compatibilizing agent. The compatibilizing agent used was maleic anhydride grafted linear low density polyethylene (LLDPE-g-MA). The LLDPE backbones of the compatibilizer are compatible with LLDPE blend component, whereas the maleic anhydride is affinated with carbonyl groups of EMA. The effectiveness of the compatibilizing agent was evaluated using different techniques like mechanical, thermal, scanning electron microscopy and rheological studies. Best compatibilization effect was found in the blend at a loading of 3 wt% of compatibilizer since at this level of compatibilizer complex viscosity, tensile strength, modulus, elongation at break, impact strength was found to be higher. The increase in the melt viscosity, storage modulus and thermal stability of the compatibilized blends indicated enhanced interactions between the discrete LLDPE and EMA phases induced by the functional compatibilizer.  相似文献   
7.
Self-assembled layers of vertically aligned titanium nanotubes were fabricated on a Ti disc by anodization. Pamidronic acids (PDAs) were then immobilized on the nanotube surface to improve osseointegration. Wide-angle X-ray diffraction, X-ray photoelectron microscopy, and scanning electron microscopy were employed to characterize the structure and morphology of the PDA-immobilized TiO2 nanotubes. The in vitro behavior of osteoblast and osteoclast cells cultured on an unmodified and surface-modified Ti disc was examined in terms of cell adhesion, proliferation, and differentiation. Osteoblast adhesion, proliferation, and differentiation were improved substantially by the topography of the TiO2 nanotubes, producing an interlocked cell structure. PDA immobilized on the TiO2 nanotube surface suppressed the viability of the osteoclasts and reduced their bone resorption activity.  相似文献   
8.
Well-dispersed single phasic flower-like zero valent iron nanoparticles have been synthesized under aerobic conditions using a facile approach without the addition of any additives or templates. The role of hydroxyl groups of polyhydroxy alcohols in controlling surface morphology of nanoparticles has been thoroughly investigated. The obtained nanoparticles have been characterized by TEM, FE-SEM, XRD and BET surface area analyzer. Electron microscopy analyses reveal that the solvent plays a pivotal role in determining the morphology of the particles. With increase in viscosity of the solvent, formations of ‘petal-like’ structures, which are joined at the center are formed. The nitrate removal efficiency of the iron nanoparticles synthesized in different solvents has been studied and it is seen that the “flower-like” iron nanoparticles were most active in the removal of nitrate. Experiments have been done by varying (i) nitrate concentrations, (ii) nanoparticle dose, and (iii) type of nanoparticles. The results conclude that highest removal efficiency (~100%) was achieved when the nanoparticle dose was 2.88 g/L, even for high nitrate concentrations up to 400 mg/L. The major highlight of this work is the fact that even though the nanoparticles synthesized in glycerol-water mixture have larger size in comparison to the other nanoparticles, still they remove the nitrates with highest efficiency.”  相似文献   
9.
Schottky barrier junctions of Al-doped n-type Zinc selenide (ZnSe) thin films of doping concentrations up to 9.7 × 1014 cm ?3 have been fabricated with Au and Ni electrodes on glass substrates by sequential thermal evaporation. All of the junctions of different doping concentrations exhibited rectifying current-voltage characteristics with a non-saturating reverse current. From the current-voltage characteristics, the different junction parameters such as ideality factor, saturation current density, series resistance, etc., were measured. Both types of junctions were found to possess a high ideality factor and a high series resistance. The barrier heights of the junctions were measured from Richardson plots and found to be around 0.8 eV. The structures were found to exhibit a poor photovoltaic effect with a fill factor not greater than 0.4. The diode quality as well as the photovoltaic performance of the diodes were improved following a short heat treatment in vacuum.  相似文献   
10.
Cryogenic heat exchangers are commonly used for industrial processes, such as air separation and natural gas liquefaction. Generally, the performance of heat exchangers is analyzed adopting constant properties for the working fluid. But, in cryogenic heat exchangers, fluids reach their critical states with significant variations in their properties. The current work is based on the effect of fluid property variations in the performance analysis of a two-fluid countercurrent cryogenic heat exchanger subject to ambient heat in a leak. Finite element method–subdomain method is used to conduct the performance analysis. The effect of fluid property variations is analyzed considering effectiveness, ∈, as the performance parameter. The percentage deviation in the effectiveness value on considering fluid property variation is determined. The relationship between effectiveness ∈ and the number of transfer units (NTUs) is obtained by plotting the ∈-NTU curve by varying the mass flow rate of the fluid flow. A maximum deviation of 16.108% in the effectiveness and 58.734% in the hot fluid exit temperature is obtained by considering fluid property variation.  相似文献   
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