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1.
Samarthya Bhagia Nidia C. Gallego Nitilaksha Hiremath David P. Harper Richard A. Lowden Richard R. Lowden Yunqiao Pu Uday Vaidya Soydan Ozcan Arthur J. Ragauskas 《应用聚合物科学杂志》2021,138(32):50797
High speed friction grinding has been used to grind plant and food substances in water but never been explored for grinding of thermoplastics like polylactic acid (PLA), low and high density polyethylene and polypropylene. Such grinding was investigated in this work and was made possible by using 0.5% guar gum solution instead of just water because increasing the viscosity of water reduced their settling and the speed of passing through the grinder. Tensile, flexural, and impact strengths of the plastics were studied and higher grinding efficiency of PLA could be explained by its low elongation-at-break compared to low density polyethylene, high density polyethylene, and polypropylene. The microplastics (2000–45 μm) were studied for mass and particle size distributions and by scanning electron microscopy, 13C CP/MAS NMR, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. In addition, viscosity of guar gum and contact angles was measured. This new technology can produce finely ground microplastics (710–45 μm) for a variety of applications. 相似文献
2.
Discontinuity-Preserving Surface Reconstruction Using Stochastic Differential Equations 总被引:1,自引:0,他引:1
We address the problem of reconstructing a surface from irregularly spaced sparse and noisy range data while concurrently identifying and preserving the significant discontinuities in depth. It is well known that, starting from either the probabilistic Markov random field model or the mechanical membrane or thin plate model for the surface, the solution of the reconstruction problem can be eventually reduced to the global minimization of a certain “energy” function. Requiring the preservation of depth discontinuities makes the energy function nonconvex and replete with multiple local minima. We present a new method for obtaining discontinuity-preserving reconstruction based on the numerical solution of an appropriate Ito vector stochastic differential equation (SDE). The reconstructed surface is found by following the sample path of the (stochastic) diffusion process that solves the SDE in question. Our central contribution is the demonstration of the efficacy of the stochastic differential equation technique for solving a vision problem. Through comparisions of the results of our method to those of the two well-known existingglobalminimization based reconstruction techniques, we show a significant improvement in the final reconstructions obtained. 相似文献
3.
Application software for Intel's 8052AH-basic microcontroller can be developed in MCS basic-52, an enhanced version of basic, using the onchip basic interpreter. The paper explores the 8052AH-basic device and its language in comparison with the standard Microsoft basic and presents some software routines and other guidelines for programmers. Control-oriented applications, as opposed to conventional number-crunching applications, are emphasized. The paper also discusses how the resources of the Intellec development system can be used to facilitate the development of application software. 相似文献
4.
Due to the exponential growth of the Internet users and wireless devices, interests on home networks have been enormously increased in recent days. In digital home networks, home services including remote access and control to home appliances as well as services offered by service providers are alluring. However, the remote control services cause digital home networks to have various security threats. Hence, for digital home networks, robust security services, especially remote user authentication, should be considered. This paper presents a robust and efficient authentication scheme based on strong-password approach to provide secure remote access in digital home network environments. The proposed scheme uses lightweight computation modules including hashed one-time password and hash-chaining technique along with low-cost smart card technology. It aims to satisfy several security requirements including stolen smart card attack and forward secrecy with lost smart card as well as functional requirements including no verification table and no time synchronization. Comparing with the existing representative schemes, it can be validated that the proposed scheme is more robust authentication mechanism having better security properties. We have conducted formal verification of the proposed scheme. 相似文献
5.
Multicasting is a useful communication method in wireless mesh networks (WMNs). Many applications in WMNs require efficient
and reliable multicast communications, i.e., high delivery ratio with low overhead among a group of recipients. In spite of
its significance, little work has been done on providing such multicast service in multi-channel WMNs. Traditional multicast
protocols for wireless and multi-hop networks tend to assume that all nodes, each of which is equipped with a single interface,
collaborate on the same channel. This single-channel assumption is not always true, as WMNs often provide nodes with multiple
interfaces to enhance performance. In multi-channel and multi-interface (MCMI) WMNs, the same multicast data must be sent
multiple times by a sender node if its neighboring nodes operate on different channels. In this paper, we try to tackle the
challenging issue of how to design a multicast protocol more suitable for MCMI WMNs. Our multicast protocol builds multicast
paths while inviting multicast members, and tries to allocate the same channel to neighboring members in a bottom-up manner.
By unifying fixed channels of one-hop multicast neighbors, the proposed algorithm can improve the performance such as reducing
multicast data transmission overhead and delay, while managing a successful delivery ratio. In order to prove such expectation
on the performance, we have implemented and evaluated the proposed solution on the real testbed having the maximum 24 nodes,
each of which is equipped with two IEEE 802.11a Atheros WLAN cards. 相似文献
6.
7.
The bactericidal characteristics of nano-copper oxide or functionalized zeolite coated concrete pipes against Acidithiobacillus thiooxidans were studied by measuring the temporal variation of bacterial dry cell weight measurement, cellular Adenosine Triphosphate production, as well as oxygen uptake rate of the aforementioned bacterium. Uncorroded (UC), severely corroded (SC), and moderately corroded (MC) concrete pipes were electrochemically coated with a nano-copper oxide, while another uncorroded concrete pipe was used to apply functionalized zeolite coating (Z2). Specimens were characterized by field emission-scanning electron microscopy, and optical microscopy. Oxygen uptake rate of the bacterium was the highest in UC followed by the MC. Oxygen uptake rate and cellular Adenosine Triphosphate decreased progressively in Z2 and SC throughout the duration of the experiment due to decline in live bacterial cell. The maximum bacterial specific growth rate was 1.1 × 10−2 day−1 for both UC and MC, with a decay rates varying from 1.4 × 10−2 to 2.6 × 10−2 day−1. The minimum concentration limits for the inhibition of the bacterium in the nano-copper oxide coated concrete pipes ranged from 2.3 mg to 2.6 mg Cu per mg dry cell weight. 相似文献
8.
9.
S. Prasanth Vaidya P. V. S. S. R. Chandra Mouli 《Multimedia Tools and Applications》2018,77(5):5609-5635
Multimedia Tools and Applications - Ownership identification and copyright protection are two major concerns for digital data. Digital watermarking provides the best solution for these issues. In... 相似文献
10.
Vaidya Chandan J.; Huger Marianne; Howard Darlene V.; Howard James H. Jr. 《Canadian Metallurgical Quarterly》2007,21(4):497
The authors examined whether a form of implicit memory that has been unambiguously dissociated from conscious awareness--learning of spatial context on the contextual cuing task introduced by M. M. Chun and Y. Jiang (1998)--is mature in childhood as predicted by an evolutionary view of cognition. School-aged children did not show reliable learning relative to adults who performed the same version of the task or another version that slowed responses to match those of children. Thus, unreliable learning in childhood was mediated by immature implicit representations of spatial context rather than by slower baseline response speed. The present finding is inconsistent with the prediction of the evolutionary view of cognition but consistent with incomplete maturation of medial temporal lobes known to mediate contextual learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献