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1.
Nano-crystal embedded PbO-P2O5 glass has been prepared and characterized by XRD and TEM measurements. The ultrasonic velocity and attenuation measured within the temperature range 80–300 K show significant structure and interesting feature with the presence of nano-crystalline region. The glass samples were prepared by melt-quench method and nano-crystals of different sizes were produced by heat treatment of the glasses for different durations of heating. All the processes were carried out at or above glass transition temperature. A theoretical model that takes account of the effects of thermally activated relaxation, anharmonicity as well as microscopic elastic inhomogeneities arising out of fluctuations has been successfully applied to interpret the variation of ultrasonic velocity and attenuation data. An interesting outcome of this application has been to propose a method for the determination of the size of nano-crystals from the ultrasonic attenuation data.  相似文献   
2.
The contribution of elastomer polarity and reactivity to bound rubber formation has been investigated. In this study, a number of elastomers of different chemical nature have been tested. The surface of the carbon black (N110) has also been modified by nitric acid oxidation in order to increase the concentration of surface functional groups. The experimental results have shown that the bound rubber formation is barely related to the polarity of the polymers. It is the reactive sites in both the elastomer and carbon black which are mainly responsible for bound rubber formation. It therefore appears that the elastomer/carbon black interaction leading to the formation of bound rubber is essentially a chemical process involving primary bond formation between elastomer and carbon black. The oxidized carbon black exhibits a higher surface activity which may be due to an increased concentration of oxygen-containing reactive surface sites, namely, phenolic hydroxyl, carboxyl, lactone, and quinone groups. © 1995 John Wiley & Sons, Inc.  相似文献   
3.
In-home technologies can support older adults' activities of daily living, provide physical safety and security, and connect elders to family and friends. They facilitate aging in place while reducing caregiver burden. One of older adults' primary concerns about in-home technologies is their potential to reduce human contact, particularly from cherished caregivers. In this exploratory in situ study, we provided an ecosystem of networked monitoring technologies to six older adults and their caregivers. We analyzed the amount and content of communication between them. The amount of noncomputer-mediated communication did not decrease through the 6-week study. The content of communication coalesced into four themes: communication about the technologies, communication facilitated by technologies, intrusiveness of technologies, and fun and playfulness with the technologies. Results suggest that in-home technologies, designed with sensitivity to older adults' primary motivations, have the potential to shape and tailor important relationships in later life.  相似文献   
4.
Continuous improvements in very-large-scale integration (VLSI) technology and design software have significantly broadened the scope of digital signal processing (DSP) applications. The use of application-specific integrated circuits (ASICs) and programmable digital signal processors for many DSP applications have changed, even though new system implementations based on reconfigurable computing are becoming more complex. Adaptable platforms that combine hardware and software programmability efficiency are rapidly maturing with discrete wavelet transformation (DWT) and sophisticated computerized design techniques, which are much needed in today’s modern world. New research and commercial efforts to sustain power optimization, cost savings, and improved runtime effectiveness have been initiated as initial reconfigurable technologies have emerged. Hence, in this paper, it is proposed that the DWT method can be implemented on a field-programmable gate array in a digital architecture (FPGA-DA). We examined the effects of quantization on DWT performance in classification problems to demonstrate its reliability concerning fixed-point math implementations. The Advanced Encryption Standard (AES) algorithm for DWT learning used in this architecture is less responsive to resampling errors than the previously proposed solution in the literature using the artificial neural networks (ANN) method. By reducing hardware area by 57%, the proposed system has a higher throughput rate of 88.72%, reliability analysis of 95.5% compared to the other standard methods.  相似文献   
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Efficacy research is insufficient and ineffective in changing practice, despite a large supporting psychotherapy efficacy literature. Concurrently, demand for supporting data and the burden on everyday practice for generating these data is increasing. The disconnect between efficacy and effectiveness is due to a lack of conceptual and methodological tools for testing efficacious procedures in real-world settings, particularly medical contexts. This article articulates the position that effectiveness studies pose more complex questions that require an alteration of conceptual and methodological frames of reference in order to make behavioral services available to the broadest patient base. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Breast cancer is one of the most common types of cancer among women globally. It is caused by mutations in the estrogen/progesterone receptors and conventional treatment methods are commonly utilized. About 70–80 percent of individuals with the early-stage non-metastatic disease may be cured. Conventional treatment is far less than the optimal ratio, as demonstrated through the high mortality rate of women with this cancer. However, conventional treatment methods like surgery, radiotherapy, and chemotherapy are not as effective as expected and lead to concerns about low bioavailability, low cellular uptake, emerging resistance, and adverse toxicities. A nanomedicine-based approach is a promising alternative for breast cancer treatment. The present era is witnessing rapid advancements in nanomedicine as a platform for investigating novel therapeutic applications and modern intelligent healthcare management strategies. This paper focuses on nanomedicine-based therapeutic interventions that are becoming more widely accepted for improving treatment effectiveness and reducing undesired side effects in breast cancer patients. By evaluating the state-of-the-art tools and taking the challenges involved into consideration, various aspects of the proposed nano-enabled therapeutic approaches have been discussed in this review.  相似文献   
9.
Since the early 1970s tremendous growth has been seen in the research of software reliability growth modeling.In general, software reliability growth models (SRGMs) are applicable to the late stages of testing in software development and they can provide useful information about how to improve the reliability of software products.A number of SRGMs have been proposed in the literature to represent time-dependent fault identification/removal phenomenon;still new models are being proposed that could fit a greater number of reliability growth curves.Often,it is assumed that detected faults axe immediately corrected when mathematical models are developed.This assumption may not be realistic in practice because the time to remove a detected fault depends on the complexity of the fault,the skill and experience of the personnel,the size of the debugging team,the technique,and so on.Thus,the detected fault need not be immediately removed,and it may lag the fault detection process by a delay effect factor.In this paper,we first review how different software reliability growth models have been developed,where fault detection process is dependent not only on the number of residual fault content but also on the testing time,and see how these models can be reinterpreted as the delayed fault detection model by using a delay effect factor.Based on the power function of the testing time concept,we propose four new SRGMs that assume the presence of two types of faults in the software:leading and dependent faults.Leading faults are those that can be removed upon a failure being observed.However,dependent faults are masked by leading faults and can only be removed after the corresponding leading fault has been removed with a debugging time lag.These models have been tested on real software error data to show its goodness of fit,predictive validity and applicability.  相似文献   
10.
For the first time, a new carbon–carbon composite electrode material for supercapacitors is prepared by simple KOH activation of waste newspaper. The amorphous nature and surface morphology of the carbon composite are investigated by X-ray diffraction (XRD), N2 adsorption/desorption and scanning electron microscopy. The surface area and pore diameter are 416 m2 g−1 and 5.9 nm, respectively. Electrochemical characteristics are evaluated by cyclic voltammetry (CV) and charge–discharge tests in 6.0 M KOH at a 1 mA cm−2 current density. The CV results reveal a maximum specific capacitance of 180 F g−1 at a 2 mV s−1 scan rate and the data explore a development of new use for waste paper into a valuable energy storage material.  相似文献   
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