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61.
A network of wireless sensors is a self-infrastructure approach with many sensory nodes. The distributed sensory nodes communicate with each other via sensory points. In wireless sensor network (WSN), the sensory nodes collect information for healthcare, military and monitoring systems. Such networks require an exclusive arrangement of the nodes to challenge inherent limitations and energy deficiency. The conventional design of a communication system consumes more energy with high latency causing degraded performance. This study provided a machine learning-based path optimization mechanism using the least energy resources in designing an effective wireless network system with enhanced three measures of network performance, including throughput, packet delivery efficiency and energy usage. The proposed methodology is validated through network simulation tools.  相似文献   
62.
We examined how the background (urban/rural) of 282 tertiary students influenced their attitudes and actions including their use of natural areas. Most considered that protection of natural spaces was ‘important’. Childhood residence influenced time spent in natural areas as young adults. When time spent in natural spaces was compared with residence status, non‐urban dwellers more frequently visited natural areas than urban dwellers. Rural residents who visited natural spaces were likely to visit more frequently than urban dwellers. The different types of passive recreation carried out in natural spaces and whether the student was involved in environmental restoration activities were not matters influenced by residence status, although there was a difference as between passive or active recreation in natural spaces. Over 80% of participants considered that ‘protection of the natural environment’ was more important than the cost of fresh produce, reduced taxes, fuel prices or ‘better use of recycled material’.  相似文献   
63.
64.
The present paper deals with an analysis of the building integrated photovoltaic thermal (BIPVT) system fitted as rooftop of a building to generate electrical energy higher than that generated by a similar building integrated photovoltaic (BIPV) system and also to produce thermal energy for space heating. A thermodynamic model has been developed to determine energy, exergy and life cycle cost of the BIPVT system. The results indicate that although the mono-crystalline BIPVT system is more suitable for residential consumers from the viewpoint of the energy and exergy efficiencies, the amorphous silicon BIPVT system is found to be more economical. The energy and exergy efficiencies of the amorphous silicon BIPVT system are found to be 33.54% and 7.13% respectively under the composite climatic conditions prevailing at New Delhi. The cost of power generation is found to be US $ 0.1009 per kWh which is much closer to that of the conventional grid power.  相似文献   
65.
Background: Type 2 diabetes mellitus is one of the leading causes of morbidity and mortality worldwide and is derived from an accumulation of genetic and epigenetic changes. In this study, we aimed to construct Insilco, a competing endogenous RNA (ceRNA) network linked to the pathogenesis of insulin resistance followed by its experimental validation in patients’, matched control and cell line samples, as well as to evaluate the efficacy of CRISPR/Cas9 as a potential therapeutic strategy to modulate the expression of this deregulated network. By applying bioinformatics tools through a two-step process, we identified and verified a ceRNA network panel of mRNAs, miRNAs and lncRNA related to insulin resistance, Then validated the expression in clinical samples (123 patients and 106 controls) and some of matched cell line samples using real time PCR. Next, two guide RNAs were designed to target the sequence flanking LncRNA/miRNAs interaction by CRISPER/Cas9 in cell culture. Gene editing tool efficacy was assessed by measuring the network downstream proteins GLUT4 and mTOR via immunofluorescence. Results: LncRNA-RP11-773H22.4, together with RET, IGF1R and mTOR mRNAs, showed significant upregulation in T2DM compared with matched controls, while miRNA (i.e., miR-3163 and miR-1) and mRNA (i.e., GLUT4 and AKT2) expression displayed marked downregulation in diabetic samples. CRISPR/Cas9 successfully knocked out LncRNA-RP11-773H22.4, as evidenced by the reversal of the gene expression of the identified network at RNA and protein levels to the normal expression pattern after gene editing. Conclusions: The present study provides the significance of this ceRNA based network and its related target genes panel both in the pathogenesis of insulin resistance and as a therapeutic target for gene editing in T2DM.  相似文献   
66.

In this paper, natural neighbor Galerkin meshless method is employed for adaptive analysis of plates and laminates. The displacement field and strain field of plate are based on Reissner–Mindlin plate theory. The interpolation functions employed here were developed by Sibson and based on natural neighbor coordinates. An adaptive refinement strategy based on recovery energy norm which is in turn based on natural neighbors is employed for analysis of plates. The present adaptive procedure is applied to classical plate problems subjected to in-plane loads. In addition to that the laminated composite plates with cutouts subjected to transverse loads are investigated. Influence of the location of the cutout and the boundary conditions of the plate on the results have been studied. The results obtained with present adaptive analysis are accurate at lower computational effort when compare to that of no adaptivity. Further, the adaptive analysis provided accurate magnitude of maximum stresses and their locations in the laminate plates with and without cutout subjected to transverse loads. Additionally, failure prone areas in the geometry of the plates subjected to loads are revealed with the adaptive analysis.

  相似文献   
67.
Thermodynamic properties of liquid Al-Mg alloys measured by the Emf method   总被引:1,自引:0,他引:1  
The thermodynamic properties of liquid Al-Mg alloys containing 0.027 to 95.50 at. Pct Mg were determined by measuring the emf, between 973 and 1073 K, of a magnesium concentration cell of the type Mg(l)|MgCl2-CaCl2 (eutectic melt, l)|Mg (in Al, l). Special attention has been given to low-magnesium aluminum alloys which are most commonly used in industry and for which definitive thermodynamic data are not reported in the literature. Alloys containing up to 12 at. Pct Mg follow Henry’s law, and the magnesium activity is given by the relation aMG = 0.88 XMG at 1073 K. Above 12 at. Pct Mg, the magnesium activity shows a small negative deviation from the ideal solution behavior. The activity of aluminum, however, closely follows the ideal solution behavior up to 75 at. Pct Mg and thereafter it shows a small negative deviation. The emf data have also been used to determine the free energy, entropy, enthalpy, and excess free energy for liquid Al-Mg alloys.  相似文献   
68.
Most of the existing intrusion detection frameworks proposed for wireless sensor networks (WSNs) are computation and energy intensive, which adversely affect the overall lifetime of the WSNs. In addition, some of these frameworks generate a significant volume of IDS traffic, which can cause congestion in bandwidth constrained WSNs. In this paper, we aim to address these issues by proposing a game theory based multi layered intrusion detection framework for WSNs. The proposed framework uses a combination of specification rules and a lightweight neural network based anomaly detection module to identify the malicious sensor nodes. Additionally, the framework models the interaction between the IDS and the sensor node being monitored as a two player non-cooperative Bayesian game. This allows the IDS to adopt probabilistic monitoring strategies based on the Bayesian Nash Equilibrium of the game and thereby, reduce the volume of IDS traffic introduced into the sensor network. The framework also proposes two different reputation update and expulsion mechanisms to enforce cooperation and discourage malicious behavior among monitoring nodes. These mechanisms are based on two different methodologies namely, Shapley Value and Vickery–Clark–Grooves (VCG) mechanism. The complexity analysis of the proposed reputation update and expulsion mechanisms have been carried out and are shown to be linear in terms of the input sizes of the mechanisms. Simulation results show that the proposed framework achieves higher accuracy and detection rate across wide range of attacks, while at the same time minimizes the overall energy consumption and volume of IDS traffic in the WSN.  相似文献   
69.
In this article, the natural convection of stratified fluid driven by the asymmetric heating and cooling of the surfaces of the concentric cylinders filled with an anisotropic porous matrix is investigated. The stratified fluid is confined between the outer surface of the inner cylinder and the inner surface of the outer cylinder while the onset transient natural convection is induced by the asymmetric heat heating/cooling of the inner surface of the outer cylinder while the outer surface of the inner cylinder is maintained at a constant temperature T = 1 $T=1$ . The present problem is governed by a pair of coupled second-order partial differential equations. To obtain the expressions for the temperature and velocity fields, the coupled mathematical equations describing the problem are systematically uncoupled such that their original orders remain unaltered. The research established that if the temperature of the outer surface of the inner cylinder equals the temperature of the inner surface of the outer cylinder, a symmetric flow occurs where two maxima velocities are observed close to the surfaces Z = 1 $Z=1\phantom{\rule{}{0ex}}$ and λ $\lambda $ of the annulus, respectively. Furthermore, for some constraints on certain values of some physical quantities in the flow solutions, the present work excellently compares with the research conducted by Jha and Oni.  相似文献   
70.
Small extracellular vesicles (sEVs) are 30–200 nm nanovesicles enriched with unique cargoes of nucleic acids, lipids, and proteins. sEVs are released by all cell types and have emerged as a critical mediator of cell-to-cell communication. Although many studies have dealt with the role of sEVs in health and disease, the exact mechanism of sEVs biogenesis and uptake remain unexplored due to the lack of suitable imaging technologies. For sEVs functional studies, imaging has long relied on conventional fluorescence microscopy that has only 200–300 nm resolution, thereby generating blurred images. To break this resolution limit, recent developments in super-resolution microscopy techniques, specifically single-molecule localization microscopy (SMLM), expanded the understanding of subcellular details at the few nanometer level. SMLM success relies on the use of appropriate fluorophores with excellent blinking properties. In this review, the basic principle of SMLM is highlighted and the state of the art of SMLM use in sEV biology is summarized. Next, how SMLM techniques implemented for cell imaging can be translated to sEV imaging is discussed by applying different labeling strategies to study sEV biogenesis and their biomolecular interaction with the distant recipient cells.  相似文献   
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