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There are different methods of optimizing energy usage of sensor nodes for increasing the life time of wireless sensor network. The first node death time is considered to be the effective life time of any network. Therefore, our objective is to adopt such routing algorithms and node deployment policy so that no individual node dies sooner while others are alive. There are different reasons for the early death of first node, which at extreme cases may lead to partition of the network. One of the important reasons for which node energy might run out early is that number of transmitted messages per geographic area unit is different. A node is more likely to run out of its energy earlier than the others in an area where message density is high. Therefore, if we can predict the areas in the network where message density is likely to be higher than the rest of the area in the network, then we can increase node density while aiming at uniform energy dissipation. The nodes which reside nearer to the sink node face huge traffic load that lead to non-uniform energy dissipation. Hence, node density nearer to the sink node has to be increased. In this paper, to increase the lifespan of wireless sensor network, we explore this concept to obtain the best possible solution. [ABSTRACT FROM AUTHOR]

As tobacco waste production from tobacco industry increases, it becomes important to convert tobacco waste into high value-added products. In this paper, the production of aroma compounds from the fast pyrolysis of tobacco waste was investigated, two kinds of tobacco waste—tobacco leaf fragments (TF), tobacco stems (TS)—and Modeng-brand cigarette tobacco (MT) were used as raw materials in a fluidized bed pyrolysis reactor. Tobacco types, pyrolysis temperatures, and bio-oil separation methods were assigned as influence factors, and the type and content of bio-oil-containing aroma compounds were defined as evaluation standards. Our results indicate that (i) the bio-oil yield under the same pyrolysis temperature (350 °C) is TS > MT > TF; (ii) when TF and MT are used as raw materials, low-temperature (about 350 °C) pyrolysis is beneficial for the production of aroma compounds, whereas TS requires higher temperature (more than 380 °C) pyrolysis; and (iii) bio-oils obtained from different separation methods contain different kinds of aroma compounds, with some compounds requiring certain separation methods. The formation and pyrolysis mechanism of nitrogen (N)-containing compounds in tobacco was also studied. The study demonstrated that nicotine converts to N-containing heterocycles because of secondary decomposition under high temperature. [ABSTRACT FROM AUTHOR]

A novel distributed power allocation scheme for analog network coding (ANC) in high signal-to-noise ratio (SNR) is proposed by using statistical channel knowledge at the transmitters only. The scheme considers nonorthogonal amplified-and- forward (NAF) protocol. In the derivation, a general Rayleigh fading multiple hop network is accurately approximated by a simpler two hop network, and the closed-formed expression for the outage probability of the simplified two hop network is obtained and optimized with respect to the power allocation. Numerical results show that the derived power allocation scheme has significant performance gain over the equal power scheme. In some cases, it approaches the optimal scheme. [ABSTRACT FROM AUTHOR]

Free-form surfaces are defined with NURBS (non-uniform rational basis spline) for most computer-aided engineering (CAE) applications. The NURBS method requires the definition of parameters such as weights, knot vectors and degree of the curves which make the configuration of the surface computationally expensive and complex. When the control points are randomly spaced in the point cloud and the topology of the desired surface is unknown, surface configuration with NURBS method becomes a challenging task. Optimization attempts for such surfaces create enormous amounts of computing data when coupled with physics solvers such as finite element analysis (FEA) tools and computational fluid dynamics (CFD) tools. In this paper, an adapted Delaunay triangulation (ADT) method for surface generation from the random points cloud is proposed and compared with widely used implicit functions based NURBS fitting method. The surface generated from ADT method can be simultaneously used with stochastic optimization algorithms (SOA) and CFD applications to search for the optimal results with minimum computational costs. It was observed while comparing ADT with NURBS-based geometry configuration that the computation time can be reduced by 3 folds. The corresponding deviation between both geometry configuration methods has been observed as low as 5% for all optimisation scenarios during the comparison. In addition, ADT method can provide light weight CFD approach as any instance of design iteration has at least half storage footprint as compared to corresponding NURBS surface. The proposed approach provides novel methodology towards establishing light weight CFD geometry, absence of which currently isolates methodologies for optimization and CFD analysis. [ABSTRACT FROM AUTHOR]

Microbial strains capable of degrading petroleum hydrocarbons were isolated from the Yellow River Delta and screened for bio-surfactant production. The bio-surfactant-producing characteristics of the isolates were evaluated, and all the isolates which could produce bio-surfactant were identified by 16S rRNA gene sequencing. The results showed that the isolates belong to Bacillus sp. (72%), Ochrobactrum sp. (0.16%), Brevundimonas sp. (0.06%) and Brevibacterium sp. (0.06%). The biodegradability of crude oil, gasoline, diesel oil and other hydrocarbons by microbial strains were studied, among which the biodegrading ability of strain P1 and strain P19 is higher than other strains. Both strains P1 and P19 can degrade n-hexane and n-hexadecane effectively and have wide substrate extensiveness. In addition, Ni promoted the biodegradability of toluene by both strain P1 and strain P19, while Pb inhibited the growth of strain P19 and decreased its ability to biodegrade toluene. The studies revealed that microbes including strain P1 and strain P19 can be utilized in bioremediation of co-contaminated water with petroleum and heavy metals including Ni and Pb. [ABSTRACT FROM AUTHOR]

Live poultry markets (LPM) are one of the most important sources of human infection with avian influenza virus (AIV). During our routine surveillance of AIV, we identified an H9N6 virus (JX-H9N6) in a LPM in Nanchang city, Jiangxi Province, China. Using Bayesian coalescent analysis, it was predicted that JX-H9N6 had originated from a reassortment event between H9N2 and H6N6 AIVs in early 2014, instead of being derived from an H9N6 virus reported previously. Mutations in HA, PB1, PA, M, and NS protein, which could increase mammalian transmission and virulence, were also detected. Currently, both H9N2 and H6N6 AIVs are widely distributed in poultry and contribute to the generation of novel reassortant viruses causing human infection. Our findings highlight the importance of enhanced surveillance in birds for early prediction of human infections. [ABSTRACT FROM AUTHOR]

Many viruses can cause respiratory diseases in humans. Although great advances have been achieved in methods of diagnosis, it remains challenging to identify pathogens in unexplained pneumonia (UP) cases. In this study, we applied next-generation sequencing (NGS) technology and a metagenomic approach to detect and characterize respiratory viruses in UP cases from Guizhou Province, China. A total of 33 oropharyngeal swabs were obtained from hospitalized UP patients and subjected to NGS. An unbiased metagenomic analysis pipeline identified 13 virus species in 16 samples. Human rhinovirus C was the virus most frequently detected and was identified in seven samples. Human measles virus, adenovirus B 55 and coxsackievirus A10 were also identified. Metagenomic sequencing also provided virus genomic sequences, which enabled genotype characterization and phylogenetic analysis. For cases of multiple infection, metagenomic sequencing afforded information regarding the quantity of each virus in the sample, which could be used to evaluate each viruses' role in the disease. Our study highlights the potential of metagenomic sequencing for pathogen identification in UP cases. [ABSTRACT FROM AUTHOR]

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