An expert enhanced coloured fuzzy Petri net approach to reconfigurable manufacturing systems involving information delays

In today’s competitive market, manufacturers need to quickly adapt to the changing demands of the customers. Reconfigurable manufacturing system (RMS) is a cost-effective system that can easily absorb frequent changes in product demands. In this article such a system is modelled using expert enhanced coloured fuzzy Petri net (EECFPN), which considers the demands of customers as a fuzzy parameter and vividly captures the reconfigurability aspect of RMS. A fuzzy control strategy (FCS) is proposed to deal with the information delays occurring during information transfer or decision implementation. After intensive computational experimentation, it has been found that FCS outperforms the alternative priority (AP) heuristic and it is considered an effective measure to deal with situations where considerable information delay is involved.     

Structural Stabilization and Piezoelectric Enhancement in Epitaxial (Ti1−xMgx)0.25Al0.75N(0001) Layers

Epitaxial (Ti_1?xMg_x)_0.25Al_0.75N(0001)/Al₂O₃(0001) layers are used as a model system to explore how Fermi‐level engineering facilitates structural stabilization of a host matrix despite the intentional introduction of local bonding instabilities that enhance the piezoelectric response. The destabilizing octahedral bonding preference of Ti dopants and the preferred 0.67 nitrogen‐to‐Mg ratio for Mg dopants deteriorate the wurtzite AlN matrix for both Ti‐rich (x < 0.2) and Mg‐rich (x ≥ 0.9) alloys. Conversely, x = 0.5 leads to a stability peak with a minimum in the lattice constant ratio c/a, which is caused by a Fermi‐level shift into the bandgap and a trend toward nondirectional ionic bonding, leading to a maximum in the expected piezoelectric stress constant e₃₃. The refractive index and the subgap absorption decrease with x, the optical bandgap increases, and the elastic constant along the hexagonal axis C₃₃ = 270 ± 14 GPa remains composition independent, leading to an expected piezoelectric constant d₃₃ = 6.4 pC N^?1 at x = 0.5, which is 50% larger than for the pure AlN matrix. Thus, contrary to the typical anticorrelation between stability and electromechanical coupling, the (Ti_1?xMg_x)_0.25Al_0.75N system exhibits simultaneous maxima in the structural stability and the piezoelectric response at x = 0.5.     

Renal medullary carcinoma: a potential sickle cell nephropathy of children and adolescents

cDNAs of potyviruses from Allium plants cultivated in different parts of the world were cloned by RT-PCR with a common primer for amplifying the 3' terminal genomic RNAs of onion yellow dwarf virus (OYDV), leek yellow stripe virus (LYSV) and, probably, of closely related potyviruses. Their nucleotide sequences bearing the viral coat protein (CP) gene and the 3' non-coding sequence were determined and compared. The degree of their sequence similarities clearly differentiated the respective viruses into 3 groups, namely OYDV "garlic-type", "wakegi-type" and LYSV group. The "garlic-type" included all the garlic isolates and two Indonesian shallot isolates. The "wakegi-type" group consisted of the isolates from Indonesian shallot and previously reported ones from Japanese Allium plants excluding garlic. The LYSV group was represented by LYSV isolates from garlic and leek. The CP sequences of LYSV group viruses differed from those of OYDV "garlic-type" and "wakegi-type" viruses (less than 60% similarities). In contrast, the sequence similarities between the OYDV "wakegi-type" and "garlic-type" isolates were 73.5 to 76.7%, suggesting they were closely related but should be discriminated as distinct species. These findings indicate that at least three distinct potyviruses, clearly distinguishable by the viral CP sequence, are present in Allium species. Finally, we concluded that the "garlic-type" viruses correspond to the typical OYDV and the "wakegi-type" viruses represent the viruses previously identified as Welsh onion yellow stripe virus (WoYSV) and shallot yellow stripe virus (SYSV). We propose the name wakegi yellow dwarf virus (WYDV) for the "wakegi-type" viruses.     

State-of-art approaches for review spammer detection: a survey

E-commerce websites are now favourite for shopping comfortably at home without any burden of going to market. Their success depends upon the reviews written by the consumers who used particular products and subsequently shared their experiences with that product. The reviews also affects the buying decision of customer. Because of this reason the activity of fake reviews posting is increasing. The brand competitors of the product or the company itself may involve in posting fraud reviews to gain more profit. Such fraudulent reviews are spam review that badly affects the decision choice of the prospective consumer of the products. Many customers are misguided due to fake reviews. The person, who writes the fake reviews, is called the spammer. Identification of spammers is indirectly helpful in identifying whether the reviews are spam or not. The detection of review spammers is serious concern for the E-commerce business. To help researchers in this vibrant area, we present the state of art approaches for review spammer detection. This paper presents a comprehensive survey of the existing spammer detection approaches describing the features used for individual and group spammer detection, dataset summary with details of reviews, products and reviewers. The main aim of this paper is to provide a basic, comprehensive and comparative study of current research on detecting review spammer using machine learning techniques and give future directions. This paper also provides a concise summary of published research to help potential researchers in this area to innovate new techniques.     

Enzyme-assisted aqueous extraction of peanut oil

Enzyme-assisted aqueous extraction of oil from oilseeds is a relatively recent technique. In the present study, peanut oil was extracted under optimized aqueous extraction conditions using Protizyme^™, which is predominantly a mixture of acid, neutral, and alkaline proteases. The optimal conditions were: enzyme concentration of 2.5% (w/w) in 10 g of peanut seeds, pH 4.0, 40°C, and 18 h incubation with constant shaking at 80 rpm. Centrifuging the mixture at 18,000 × g for 20 min separated the oil with a recovery of 86–92%. The merits of this process over existing solvent extraction and/or mechanical pressing methods are discussed.     

Magnetic and dielectric studies of barium hexaferrite (BaFe 12 O 19 ) ceramic synthesized by chemical route

Barium hexaferrite BaFe12O19 (BHF) ceramic was synthesized by chemical route on sintering at 1050 °C for 12 h. The synthesized material was characterized by XRD, SEM, AFM and TEM analysis. Metal oxide stretching frequencies corresponding to Fe-O, Ba-O, and Fe-O-Fe bands are confirmed by FTIR studies. The hexagonal nature of the BHF ceramic was confirmed by TEM analysis and Rietveld refinement with space group P63/mmc. The particle size observed by TEM is 175 nm. The root means square and average roughness were found to be 61.048 nm and 44.025 nm respectively. The M-T and M-H hysteresis loop indicates temperature dependent ferromagnetic behavior of BHF ceramic. The temperature and frequency dependent dielectric properties were explained by Maxwell-Wagner theory. The value of dielectric constant (ε′) for BHF ceramic was found to be 22× 103 at 100 Hz and 483 K.     

Transient and steady‐state conduction in ethyl cellulose (EC)–poly(methyl methacrylate) (PMMA) blends

Transient discharging currents and steady‐state conduction in solution‐grown ethyl cellulose (EC)–poly(methyl methacrylate) (PMMA) blends measured as a function of temperature (30–80 °C) and field strength (10–100 kV cm⁻¹) are reported. Transient currents are found to follow the Curie–VonSchweidler law, characterized by different slopes in short‐ and long‐time regions, having different decay constant values lying between 0.75–0.99, and 1.68–1.95. The corresponding activation energies are found to increase with time of measurement of discharge current. Isochronal characteristics (ie current versus temperature plots at constant times) constructed from the data seem to reveal a broad peak observed at 60 °C. The dependence of dark current at different temperatures (30–80 °C) in a metal (1)–EC–PMMA blend–metal (1)/(2) system on the applied voltage in the range 10–100 kV cm⁻¹ has also been studied; the current is found to be strongly temperature dependent. Dipole polarization and space charge resulting from trapping of injected charge carriers in energetically distributed traps and induced dipoles created because of the piling up of charge carriers at the phase boundary of the heterogeneous components of the blend are considered to account for the observed transient currents. The results of current–voltage measurement on blends are interpreted to show that the low‐field steady‐state conduction is ohmic in nature, and in high fields the charge carriers are generated by field‐assisted lowering of coulombic barriers at the traps and are conducted through the bulk of the material by a hopping process between the localized states by a Jonscher–Ansari Poole–Frenkel mechanism. The modified P–F barrier is calculated to be 1.89 × 10⁻¹⁹ J (1.18 eV), 1.92 × 10⁻¹⁹ J (1.20 eV) and 1.95 × 10⁻¹⁹ J (1.22 eV) for P₁, P₂ and P₃ blends, respectively. © 2000 Society of Chemical Industry     

Carbide-Free Bainite: Compromise between Rate of Transformation and Properties

By identifying the relationship between the time required to obtain bainite and parameters such as the transformation temperature and carbon concentration, it has been possible to institute a design procedure that led to the desired mechanical properties and transformation characteristics. The work has also identified difficulties in the calculation of tensile elongation on the basis of a percolation model, which suggests that fracture occurs when the fraction of austenite drops below the percolation threshold in the microstructure.     

CFD modeling of pressure drop and drag coefficient in fixed and expanded beds

The aim of this study is computational fluid dynamic (CFD) simulation of the single-phase pressure drop in fixed and expanded beds. A fixed bed with a column to particle diameter ratio (D/d_p) of 5 and having 151 particles arranged in 8 layers was taken as a computational geometrical model. In the case of expanded beds, 0.605 voidage bed consisted of 105 particles and 0.783 voidage bed consisted of 55 particles. Simulations were performed in the creeping, transition and turbulent flow regimes, where Reynolds number (d_pV_Lρ_L/μ_L) was varied from 0.1 to 10,000. The deviations from Ergun's equation due to the wall effects, which are important in D/d_p < 10 beds, were well explained by the CFD simulations. Thus, an increase in the pressure drop was observed due to the wall friction in the creeping flow, whereas, in turbulent regime a decrease in the pressure drop was observed due to the channeling near the wall. Energy balance has been established through the CFD predicted values of energy dissipation rates (viscous as well as turbulent).