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111.

The intention behind this article is to devise a fresh clustering algorithm for Wireless Sensor Networks. The major aspiration is to curtail the energy utilization at the cluster building and data transmission levels to the Base Station. The algorithms offered are not dedicated to a particular type of sensor network or a specific application. We consider several parameters when choosing Cluster Head such as energy, degree and distance. These parameters have been studied separately or in combination in several literature works and their efficiency in terms of energy utilization and structural stability have been shown. The proposed approach is termed as the Distance Energy Evaluated (DEE) Approach. The DEE approach has lower intricacy in message size. The proposed approach is tested by running various MATLAB simulations. The results illustrate that our proposed protocol has shown significant improvement as compared to other approaches in terms of the lifespan of the network and energy usage.

  相似文献   
112.
Software Quality Journal - Analyzing the behavior of sensors is becoming one of the key challenges due to their increasing use for decision making in IoT systems. The paper proposes an approach for...  相似文献   
113.
Leaf rust and powdery mildew are two important foliar diseases in wheat. A recombinant inbred line (RIL) population, obtained by crossing two bread wheat cultivars (‘Victo’ and ‘Spada’), was evaluated for resistance to the two pathogens at seedling stage. Upon developing a genetic map of 8726 SNP loci, linkage analysis identified three resistance Quantitative Trait Loci (QTLs), with ‘Victo’ contributing the resistant alleles to all loci. One major QTL (QPm.gb-7A) was detected in response to Blumeria graminis on chromosome 7A, which explained 90% of phenotypic variation (PV). The co-positional relationship with known powdery mildew (Pm) resistance loci suggested that a new source of resistance was identified in T. aestivum. Two QTLs were detected in response to Puccinia triticina: a major gene on chromosome 5D (QLr.gb-5D), explaining a total PV of about 59%, and a minor QTL on chromosome 2B (QLr.gb-2B). A positional relationship was observed between the QLr.gb-5D with the known Lr1 gene, but polymorphisms were found between the cloned Lr1 and the corresponding ‘Victo’ allele, suggesting that QLr.gb-5D could represent a new functional Lr1 allele. Lastly, upon anchoring the QTL on the T. aestivum reference genome, candidate genes were hypothesized on the basis of gene annotation and in silico gene expression analysis.  相似文献   
114.
The objective of this study was to evaluate some of the mechanical and physical properties of experimental particleboard panels manufactured from rubberwood (Hevea brasiliensis) bonded using oil palm starch, wheat starch, and urea formaldehyde (UF) at a density of 0.60 g/cm3. Bending characteristics, internal bond strength, thickness swelling, and water absorptions of the samples were determined based on Japanese Industrial Standard (JIS). Overall mechanical properties for natural binder oil palm starch resulted in higher values than those made from wheat starch. The highest internal-bonding strength (IB) value of 0.41 N/mm2 was determined for the samples made from oil palm starch. Dimensional stability in the form of thickness swelling of the samples made from oil palm starch had higher values, ranging from 4.24 to 22.84% than those manufactured from wheat starch. Natural adhesive showed comparable strength with panels manufactured with UF. Overall results meet the Japanese Industrial Standard (JIS) requirements except for water absorption and thickness swelling of the samples.  相似文献   
115.
Limited data are available on the serum levels of different sphingomyelin (CerPCho) and ceramide (CER) species in sickle‐cell disease (SCD). This study was aimed at identifying the levels of C16–C24 CerPCho and C16–C24 CER in serum obtained from SCD patients and controls. Circulating levels of neutral sphingomyelinase (N‐SMase) activity, ceramide‐1‐phosphate (C1P), and sphingosine‐1‐phosphate (S1P) were also determined. Blood was collected from 35 hemoglobin (Hb)A volunteers and 45 homozygous HbSS patients. Serum levels of C16–C24 CerPCho and C16–C24 CER were determined by an optimized multiple reaction monitoring (MRM) method using ultrafast liquid chromatography (UFLC) coupled with tandem mass spectrometry (MS/MS). Serum activity of N‐SMase was assayed by standard kit methods, and C1P and S1P levels were determined by enzyme‐linked immunosorbent assay. A significant decrease was observed in the serum levels of C18–C24 CerPCho in patients with SCD compared to controls. No significant difference was found in C16 CerPCho levels between the two groups. Very‐long‐chain C22–C24 CER were significantly decreased in SCD, while long‐chain C16–C20 CER levels showed no significant difference between SCD patients and controls. Significant positive correlation was found between the serum total cholesterol levels and C18–C24 CerPCho and C22–C24 CER in SCD patients. Patients with SCD had significantly elevated serum activity of N‐SMase as well as increased circulating levels of C1P and S1P compared to controls. The decrease in serum levels of C18–C24 CerPCho in patients with SCD was accompanied by decreased levels of C22–C24 CER. Future studies are needed to understand the role of decreased CerPCho and CER in the pathophysiology of SCD.  相似文献   
116.
The current study presents results from a series of numerical analyses of non‐Newtonian liquid film formation on a rotating spoked annulus. The film flow of a common type of polyester, poly(ethylene terephthalate) (PET), on a vertically rotating disk was modeled numerically. Two different molecular weights, corresponding to different viscosities for PET, and under flow at different rotating speeds, were considered. The film thickness profile was obtained at different radial and angular positions of the rotating disk in the simulations, which is beneficial in calculating the volume of polymer taken up by the rotating disk and also in calculating the volumetric flow rates on the disk. Two types of disks, including a standard solid disk and a number of hollow disk designs with spoked annuli, were considered, and the film flow was modeled using a volume of fluid computational fluid dynamics analysis. The analyses of flow over spoked annulus designs highlighted the advantage of such designs over the use of a conventional solid disk. It was found that the variation in the film thickness for the spoked annulus was lower than that for the conventional solid disk. The parametric study also provided a favorable spoked annulus design for which the film thickness was essentially constant. A constant film thickness would provide a constant film flow, which can be a benefit to many industrial applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44943.  相似文献   
117.
Cubane molecules hold great potential for medicinal chemistry applications due to their inherent stability and low toxicity. In this study, we report the synthesis of a cubane derivative phosphoramidite for the incorporation of cubane into small interfering RNAs (siRNAs). Synthetic siRNAs rely on chemical modifications to improve their pharmacokinetic profiles. However, they are still able to mediate sequence-specific gene silencing via the endogenous RNA interference pathway. We designed a library of siRNAs bearing cubane at different positions within the sense and antisense strands. All siRNAs showed excellent gene-silencing activity, with IC50 values ranging from 45.4 to 305 pM. Incorporating the cubane modification in both the sense and antisense strand led to viable duplexes with good biological activity. To the best of our knowledge, this is the first report of siRNAs bearing a cubane derivative within the backbone.  相似文献   
118.
The objective of this study was to determine the isothermal drying kinetics of Acacia mangium wood blocks by employing a relative humidity-controlled drying chamber. A model was developed based on solution of Fick's second law and evaluated through the coefficient of determination (R 2 ), sum of square error (SSE), root mean square error (RMSE), and reduced chi-square (χ 2 ). This model was compared to semi-theoretical models which are commonly used to describe the drying behavior of biomass in previous studies. The porosity and shrinkage characteristics of dried specimens were also evaluated. Based on the findings in this work, it was determined that the proposed model resulted in an excellent fit with experimental data for all four drying temperature levels of 30, 35, 40, and 45 ° C to describe the isothermal drying kinetics of Acacia mangium . It appears that volumetric shrinkage of the samples decreased quadratically with decreasing moisture ratio. The activation energy of the drying process was determined to be 41.07 kJ/mol.  相似文献   
119.
This review article is aimed at reporting the recent development of hybrid fillers used in vulcanized rubber. This review will consider the synergistic effect of rubber hybrid composites that consist exclusively of conventional fillers; carbon black and/or silica as the primary filler, which are combined with secondary fillers from various sources. The discussions are mainly focused on the analyses and comparisons of the curing characteristics, morphology, and mechanical properties of the rubber composite-filled hybrid fillers. The compatibility and the existence of synergistic effects between the different types of fillers show the potential for development and application in rubber industries.  相似文献   
120.
The goal of abstractive summarization of multi-documents is to automatically produce a condensed version of the document text and maintain the significant information. Most of the graph-based extractive methods represent sentence as bag of words and utilize content similarity measure, which might fail to detect semantically equivalent redundant sentences. On other hand, graph based abstractive method depends on domain expert to build a semantic graph from manually created ontology, which requires time and effort. This work presents a semantic graph approach with improved ranking algorithm for abstractive summarization of multi-documents. The semantic graph is built from the source documents in a manner that the graph nodes denote the predicate argument structures (PASs)—the semantic structure of sentence, which is automatically identified by using semantic role labeling; while graph edges represent similarity weight, which is computed from PASs semantic similarity. In order to reflect the impact of both document and document set on PASs, the edge of semantic graph is further augmented with PAS-to-document and PAS-to-document set relationships. The important graph nodes (PASs) are ranked using the improved graph ranking algorithm. The redundant PASs are reduced by using maximal marginal relevance for re-ranking the PASs and finally summary sentences are generated from the top ranked PASs using language generation. Experiment of this research is accomplished using DUC-2002, a standard dataset for document summarization. Experimental findings signify that the proposed approach shows superior performance than other summarization approaches.  相似文献   
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