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101.

Internet of Things (IoT) is being used by a large number of applications and transmitting huge amounts of data. IPv6 routing protocol for low power and lossy networks (RPL) is being standardized for routing in IoT networks. However, it is difficult to handle such huge transmission as it is initially designed for Low power and lossy networks. In this paper, we present the mechanism for the reduction of overhead from the congested parent node by offloading its partial load. For offloading the packet, a suitable neighbor is selected based on its status of energy, buffer, link quality, number of child nodes, and distance. This approach focuses on the enhancement of RPL by including the mechanism for congestion control. The approach reduces the delay and packet loss rate while avoiding congestion in a suitable manner. The proposed approach is beneficial in terms of throughput and packet receiving ratio as compared to the comparative approaches.

  相似文献   
102.
Fish processing industries result in an ample number of protein-rich byproducts, which have been used to produce protein hydrolysate (PH) for human consumption. Chemical, microbial, and enzymatic hydrolysis processes have been implemented for the production of fish PH (FPH) from diverse types of fish processing byproducts. FPH has been reported to possess bioactive active peptides known to exhibit various biological activities such as antioxidant, antimicrobial, angiotensin-I converting enzyme inhibition, calcium-binding ability, dipeptidyl peptidase-IV inhibition, immunomodulation, and antiproliferative activity, which are discussed comprehensively in this review. Appropriate conditions for the hydrolysis process (e.g., type and concentration of enzymes, time, and temperature) play an important role in achieving the desired level of hydrolysis, thus affecting the functional and bioactive properties and stability of FPH. This review provides an in-depth and comprehensive discussion on the sources, process parameters, purification as well as functional and bioactive properties of FPHs. The most recent research findings on the impact of production parameters, bitterness of peptide, storage, and food processing conditions on functional properties and stability of FPH were also reported. More importantly, the recent studies on biological activities of FPH and in vivo health benefits were discussed with the possible mechanism of action. Furthermore, FPH-polyphenol conjugate, encapsulation, and digestive stability of FPH were discussed in terms of their potential to be utilized as a nutraceutical ingredient. Last but not the least, various industrial applications of FPH and the fate of FPH in terms of limitations, hurdles, future research directions, and challenges have been addressed.  相似文献   
103.
Organically modified nanoclays have been reported to play the role of a compatibilizer for immiscible polymer blends. However, the mechanism of compatibilization by nanoclay has been reported differently. In this work, we investigated the exact mechanism of compatibilization of nanoclay in immiscible polystyrene (PS)/poly(methyl methacrylate) (PMMA) blend in the presence of sodium-montmorillonite (Na-MMT) through selective dispersion of clay in the matrix phase. Through a detailed investigation of the morphology of PS/PMMA/Na-MMT blend nanocomposites, the plausible mechanism behind the compatibilization effect of clay in immiscible blends has been proposed.  相似文献   
104.
The bioavailability of curcumin from turmeric, Biocurcumax? and as plain curcumin was investigated using conventional vehicles by a non-everted rat intestinal model. Results of ex vivo intestinal permeability studies showed an enhancement in the permeability of curcumin with increase in lipophilicity of the vehicle used. Maximum permeability of curcumin was obtained from corn oil (13.4%) followed by clarified butter (9.82%), milk (4.24%) and aqueous suspension (1.66%) in 8 h. Another very interesting and important observation was that the permeation of curcumin was more from turmeric and Biocurcumax? than from plain curcumin. These studies strongly suggest that curcumin may be consumed as turmeric/Biocurcumax? in lipophilic vehicles instead of plain curcumin for maximum beneficial effects.  相似文献   
105.
106.
Accident analysis involves the use of both quantitative and qualitative data in decision-making. The aim of this paper is to demonstrate the synthesis of relevant quantitative and qualitative evidence for accident analysis and for planning a large and diverse portfolio of highway investment projects. The proposed analysis and visualization techniques along with traditional mathematical modeling serve as an aid to planners, engineers, and the public in comparing the benefits of current and proposed improvement projects. The analysis uses data on crash rates, average daily traffic, cost estimates from highway agency databases, and project portfolios for regions and localities. It also utilizes up to two motivations out of seven that are outlined in the Transportation Equity Act for the 21st Century (TEA-21). Three case studies demonstrate the risk-based approach to accident analysis for short- and long-range transportation plans. The approach is adaptable to other topics in accident analysis and prevention that involve the use of quantitative and qualitative evidence, risk analysis, and multi-criteria decision-making for project portfolio selection.  相似文献   
107.
The multiwalled carbon nanotubes (MWCNTs) produced by catalytic chemical vapor deposition (CCVD) route were heat treated to 2500 °C to improve the structure, morphology and purity level. The process has lead to substantial reduction in the catalytic impurity along with an improved thermal stability and degree of graphitization of these tubes that can possibly lead to its better utilization in various applications. The structural changes following heat treatment have been correlated using various characterization techniques such as Raman spectroscopy, X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, thermo gravimetric analysis and electron paramagnetic resonance spectroscopy. The electrical and mechanical properties of the polymer composites prepared with heat treated MWCNT show improved properties over the one prepared by as produced MWCNT.  相似文献   
108.
AuNPs ranging in 20 to 300 nm size were synthesized at a room temperature using Yucca filamentosa leaf extract. Diverse nanomaterial morphologies were obtained by varying the extract concentration, reaction pH, and temperature. While low volumes of extract (0.25 and 0.5 mL) induced the formation of microscale Au sheets with edge length greater than 1 μm, high volumes yielded spherical particles ranging from 20 to 200 nm. Varying pH of the solution significantly influenced the particle shape with the production of largely spherical particles at pH 5 to 6 and truncated triangles at pH 2. Separation of multidimensional nanostructures was achieved using a novel method of sucrose density gradient centrifugation. The catalytic function of Yucca-derived AuNPs was demonstrated by degradation of a wastewater dye: methylene blue using spectrophotometric measurements over time. Treatment with Au nanosheets and spheres demonstrated methylene blue degradation approximately 100% greater than the activity in control at 60 min.  相似文献   
109.
City logistics is a discipline specialized to cope with the sustainability problems encountered in urban freight transport. A key characteristic of it is the heterogeneity of the stakeholders involved. Besides the traditional logistics actors such as shippers, carriers and receivers that share consistent interests (i.e. price and quality), city logistics highly respect the interests of public administrators and citizens that care more about the social welfare. To reach an optimal balance between private and public benefit, it is necessary to understand and in turn forecast the behavior pattern of different groups. In recent years, agent-based modeling has been practiced as an unconventional tool to fulfill this task for its strong capability on capturing the dynamic behavior of individual stakeholders and their interconnections. Referring to other domains (e.g. energy system) where the application of agent-based modeling is relatively mature, a following urgency is to achieve interoperability and in turn reusability between models via introducing formal ontology as a shared template with which developers can standardize their models. This paper introduces an initiative of developing an ontology that formalizes the domain knowledge of city logistics.  相似文献   
110.
In this study, copper nanoparticles (Cu NPs) were synthesised by using diethylenetriamine as a protective agent in chemical reduction method. The obtained nanoparticles were characterised by various spectroscopic techniques like powder X-ray diffraction (PXRD), Fourier transform infrared (FTIR), UV–visible spectroscopy, energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermal analysis (TG/DTA). The structure and composition were estimated by PXRD, FTIR, EDS, UV–visible and TG/DTA techniques, while particles size and morphology behaviours were investigated by SEM and TEM instrumentation. A noteworthy, average particle size of nanoparticles was found around 40 nm with spherical shapes. Furthermore, the applications part of NPs were studied as a catalyst for one-pot solvent-free green synthesis of 3,4-dihydropyrano[c]chromenes from different aromatic aldehydes, malonitrile and 4-hydroxycoumarin by stirring at 80 °C. Moreover, the antibacterial properties of NPs were assessed in vitro against human bacterial pathogen such as Staphylococcus aureus, Escherichia coli, Klebsiella sp. and Pseudomonas aruginosa using agar well diffusion method. Gram positive bacteria S. aureus (18 mm) exhibited a maximum zone of inhibition at 60 µg/ml of Cu NPs. Nonetheless, antibacterial activities of Cu NPs (10–100 µg) were compared with four well-known antibiotics likes amikacin (30 mcg), ciprofloxacin (5 mcg), gentamicin (5 mcg) and norfloxacin (10 mcg). This study indicates that Cu NPs exhibited a strong antibacterial activity against all the test pathogens even at lower concentration.  相似文献   
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